bluuebunny/crossref_metadata_2025 huggingface dataset:
Phospholipid hydroperoxides are detoxified by phospholipase A2 and GSH peroxidase in rat gastric mucosa
Authors: Miyamoto Sayuri , Dupas Coralie , Murota Kaeko , Terao Junji
Published: November 2006

The aim of this study was to determine the metabolic fate of phospholipid hydroperoxides (PLOOH) in rat gastric mucosa. Here we report evidence concering the mechanism for PLOOH detoxification in gastric mucosa homogenate. Analysis by the TLC blot technique showed that the gastric mucosa has the highest potential to eliminate 1‐palmitoyl‐2‐linoleoyl‐phosphatidylcholine hydroperoxides (PL‐PtdChoOOH) compared with the intestinal mucosa and liver. Major products detected after incubation with gastric mucosa were the partially reduced linoleic acid hydroperoxides (LAOOH) and lysophosphatidylcholine, indicating the involvement of phospholipase A2 (PLA2) in the elimination pathway. Using unilamellar vesicles, we demonstrated that gastric mucosal PLA2 does not distinguish between PLOOH and intact phospholipids. Although gastric mucosal PLA2 activity efficiently eliminated excess amounts of PLOOH, the complete reduction of LAOOH was dependent on the supply of exogenous GSH. In a separate experiment, administration of egg yolk PtdChoOOH to rats for 6 d significantly elevated GSH peroxidase (GPx) activity in the gastric mucosa. We concluded that excess amounts of PLOOH are efficiently eliminated through the hydrolysis by PLA2, and the subsequent reduction of FA hydroperoxide by GPx is the critical step for complete detoxification of oxidized phospholipids in the stomach.
Tissue deposition of n−3 FA pathway intermediates in the synthesis of DHA in rainbow trout (Oncorhynchus mykiss)
Authors: Bell Michael V. , Dick James R. , Porter Alexander E. A.
Published: November 2006

The tissue distribution of newly synthesized 22∶6n‐3 and intermediate PUFA was examined in rainbow trout to further our understanding of the metabolism of this EFA in fish. Rainbow trout were fed a pulse of deuterated linoleic acid (D5−17,17,18,18,18−18∶3n‐3), and the tissue distribution of deuterated anabolites was determined at interval up to 35 d post‐dose by GC‐negative chemical ionization MS of the pentafluorobenzyl derivatives. D5−22∶6n‐3 was the major deuterated FA in liver and cecal mucosa 2 and 5 d post‐dose. All the n−3 FA pathway intermediates were found in liver, cecal mucosa, and blood including D5−24∶5n‐3 and D5−24∶6n‐3. Brain and eyes also contained the full suite of intermediate deuterated FA, but with a different profile from liver when analyzed over a longer time course up to 35 d. D5−20∶5n‐3 was the major component in brain up to 7 d, after which D5−22∶6n‐3 became predominant, but D5−22∶5n‐3 constituted ca. 20% of FA throughout the time period. The pattern in eyes was similar but less pronounced. In visceral adipose tissue there was a much greater accumulation of the initial substrate, D5−18∶3n‐3, with D5−18∶4n‐3 and D5−22∶6n‐3 the predominant deuterated FA at all time points. There was a similar though less pronounced trend in eye socket adipose tissue. The C24 PUFA were not detected in visceral fat and barely detected in eye socket fat. The results show that the kinetics of accumulation and depletion of the various n−3 PUFA differ between tissues. The presence of pathway intermediate FA provides evidence that liver and ceca possess the full metabolic pathway for synthesis of 22∶6n‐3, whereas brain and eyes are less active, with an accumulation of pentaene intermediate FA, and adipose tissue is inactive.
Lipase‐catalyzed methanolysis of triricinolein in organic solvent to produce 1,2(2,3)‐diricinolein
Authors: Turner Charlotta , He Xiaohua , Nguyen Tasha , Lin Jiann‐Tsyh , Wong Rosalind Y. , Lundin Robert E. , Harden Leslie , McKeon Thomas
Published: November 2006

The objective of this study was to find the optimal parameters for lipase‐catalyzed methanolysis of triricinolein to produce 1,2(2,3)‐diricinolein. Four different immobilized lipases were tested, Candida antarctica type B (CALB), Rhizomucor miehei (RML), Pseudomonas cepacia (PCL), and Penicillium roquefortii (PRL). n‐Hexane and diisopropyl ether (DIPE) were examined as reaction media at three different water activities (aw), 0.11, 0.53, and 0.97. The consumption of triricinolein and the formation of 1,2(2,3)‐diricinolein, methyl ricinoleate, and ricinoleic acid were followed for up to 48 h. PRL gave the highest yield of 1,2(2,3)‐diricinolein. Moreover, this lipase showed the highest specificity for the studied reaction, i.e., high selectivity for the reaction with triricinolein but low for 1,2(2,3)‐diricinolein. Recoveries of 93 and 88% DAG were obtained using PRL in DIPE at aw of 0.11 and 0.53, respectively. Further, NMR studies showed that a higher purity of the 1,2(2,3)‐isomer vs. the 1,3‐isomer was achieved at higher aw (88% at aw=0.53), compared to lower aw (71% at aw=0.11). The DAG obtained was acylated by the DAG acyltransferase from Arabidopsis thaliana. Therefore, this enzymatic product is a useful enzyme substrate for lipid biosynthesis. Accordingly, the use of PRL in DIPE at aw 0.53 is considered optimal for the synthesis of 1,2(2,3)‐diricinolein from triricinolein.
Intramuscular injection of antigens and adjuvant preferentially decreases 18∶2n−6 and 18∶3n−3 in pig neck muscle
Authors: Bazinet Richard P. , Douglas Holly , McMillan Ewen G. , Wilkie Bruce N. , Cunnane Stephen C.
Published: November 2006

Linoleic (18∶2n−6) and α‐linolenic acids (18∶3n−3) have many important physiological functions including immunomodulation. We tested how immunization influences the metabolism of 18∶2n−6 and 18∶3n−3 in the neck muscle of pigs. At 35 d old, pigs received either an intramuscular neck injection containing hen egg white lysozyme (HEWL), killed Mycobacterium tuberculosis, and Freund's complete adjuvant (immunized) or PBS (control). At 49 d old, immunized pigs received a booster injection of HFWI and Freund's incomplete adjuvant, and the control pigs received PBS into the neck. At 56 d old, all pigs received an intradermal injection of Mycobacterium bovis into the hind leg to induce a delayed‐type hypersensitivity (DTH) reaction. At 57 d old, immunized pigs had a twofold increase in serum haptoglobin, a 10‐fold increase in antibodies to HEWL, and the skinfold at the DTH reaction site was 10 times thicker than the controls. Both 18∶2n−6 and 18∶3n−3 (% composition) were approximately 25% lower in muscle IG, 40% lower in FFA, 50% lower in phospholipids, but not different in cholesteryl esters of the neck muscle of immunized pigs. The antigens in this model induce an increased response in the innate (haptoglobin), humoral (antibodies), and cellular (DTH) immune systems as well as a preferential decrease of 18∶2n−6 and 18∶3n−3 in the inflamed neck muscle. It appears that 18∶2n−6 and 18∶3n−3 are preferentially metabolized (possibly β‐oxidized) in response to antigens.
Ingestion of plasmalogen markedly increased plasmalogen levels of blood plasma in rats
Authors: Nishimukai Megumi , Wakisaka Takuya , Hara Hiroshi
Published: November 2006

Plasmalogens, a subclass of phospholipids, are widely distributed in human and animals, and are taken into the body as food. However, no data exist on the intestinal absorption or fate of ingested plasmalogen. Here, we determined whether dietary plasmalogen is absorbed and whether blood and tissue concentrations increased in normal male Wistar rats by using four separate experiments. Phospholipids containing more than 20 wt% of plasmalogen extracted from the bovine brain were incorporated into test diets (10–15 wt%). In experiment 1, we estimated the absorption rate by measuring the plasmalogen vinyl ether bonds remaining in the alimentary tract of rats after the ingestion of 2 g of test diet containing 91 μmol plasmalogen. The absorption rate of plasmalogen was nearly 80 mol% after 4 h, comparable to the total phospholipid content in the test diet. In experiment 2, we observed no degradation of the plasmalogen vinyl ether bonds under in vitro conditions simulating those of the stomach and small intestinal lumen. In experiment 3 we confirmed a comparable absorption (36 mol%) by using a closed loop of the upper small intestine in anesthetized rats 90 min after injecting a 10 wt% brain phospholipid emulsion. Feeding a test diet containing 10 wt% brain phospholipids for 7 d increased plasmalogen concentration threefold in blood plasma and by 25% in the liver; however, no increases were seen in blood cells, skeletal muscle, brain, lungs, kidneys, or adipose tissue (experiment 4). We concluded that dietary plasmalogen is absorbed from the intestine and contributes to a large increase in plasmalogen levels in blood plasma.
Effect of starvation on lipid metabolism and stability of DHA content of lipids in horse mackerel (Trachurus japonicus) tissues
Authors: Osako Kazufumi , Kuwahara Koichi , Saito Hiroaki , Hossain Mohammed Anwar , Nozaki Yukinori
Published: November 2006

For the purpose of characterizing the effect of starvation on 22∶6n−3 (DHA) content in marine fish tissues, horse mackerel (Trachurus japonicus) were reared in a tank containing filtered, sterilized seawater under nonfeeding conditions for 107 d (survival rate of the fish was 96.5%). The crude total lipids (TL) of ordinary dorsal muscle, dorsal skin, and viscera of the starved individuals were separated into classes on silicic acid columns, and the constituents of the TL were quantified by gravimetric recovery from column chromatography. The TL, initially>85% TAG in dorsal muscle, and even more in skin lipids, decreased dramatically within the first 44 d of starvation, and then decreased more gradually during the remainder of the test period, whereas the visceral TL decreased more slowly. The percentages of both saturated and monoenoic FA in the muscle TL also decreased somewhat, but those of DHA increased significantly in muscle during the test periods. Decreases in PE and PC initially were much smaller than TAG, but DHA levels remained high in both PE and PC. These findings indicate that all of the FA in the depot lipids of horse mackerel tissues are easily metabolized for energy production during starvation, but DHA in muscle lipids of the starved fish was maintained at a consistently high level, indicating that starvation did not affect DHA stability in phospholipids. The findings suggest that preservation of DHA in cell membrane lipid PE and PC is necessary for self‐protection functions in starving fish.
Simple chemical syntheses of TAG monohydroperoxides
Authors: Hui Shu‐Ping , Murai Tsuyoshi , Yoshimura Teruki , Chiba Hitoshi , Kurosawa Takao
Published: November 2006

For the purpose of synthesizing standards to be used in the quantification of TAG hydroperoxides, three TAG (1,2‐dioleoyl‐3‐palmitoylglycerol, 1‐oleoyl‐2‐linoleoyl‐3‐palmitoylglycerol, and triolein) monohydroperoxides were chemically synthesized as authentic specimens. TAG were prepared by using a simple condensation in pyridine of glycerol and the corresponding acid chlorides. These TAG were then converted into monohydroperoxides by a photosensitized peroxidation. The synthesized monohydroperoxides were analyzed by normal‐phase and RP‐HPLC. The results of normal‐phase HPLC analysis showed that monohydroperoxides from a corresponding TAG were a mixture of regioisomers. In RP‐HPLC, however, the regioisomers of monohydroperoxides were not separated and gave a single peak, which may improve the sensitivity for the detection of TAG monohydroperoxides. In this study TAG monohydroperoxide standards were synthesized; these will be useful for the study of yet unknown biological and pathological roles of TAG hydroperoxides.
Novel ceramides and a new glucoceramide from the roots of Incarvillea arguta
Authors: Luo Yinggang , Yi Jinhai , Li Bogang , Zhang Guolin
Published: November 2006

Novel ceramides, rel‐(3S,4S,5S)‐3‐[(2R)‐2‐hydroxycosanoyl‐hexacosanoylamino]‐4‐hydroxy‐5‐[(4Z)‐tetradecane‐4‐ene]‐2,3,4,5‐tetrahydrofuran (1a‐g), and a new glucoceramide, 1‐O‐β‐d‐glucopyranosyl‐(2S,3S,4R,8E)‐2‐[(2R)‐2‐hydroxytetracosanoylamino]‐1,3,4‐octodecanetriol‐8‐ene (2) were isolated from the aqueous ethanolic extract of the roots of Incarvillea arguta, together with eight known compounds: β‐sitosterol (3), oleanolic acid (4), ursolic acid (5), piperin (6), maslinic acid (7), β‐sitosterol 6′‐O‐acyl‐β‐d‐glucopyranoside (8), 8‐epideoxyloganic acid (9), and plantarenaloside (10). Their structures were elucidated on the basis of spectral data including IR, MS, NMR [1H NMR, 13C NMR (distortionless enhancement by polarization transfer), 1H−1H COSY, heteronuclear multiplequantum coherence, and heteronuclear multiple‐bond coherence correlations]. The relative configurations were established by nuclear Overhauser effect spectroscopy experiments and by comparison of the NMR spectral data and coupling constants with those already reported in the literature.
Dietary fish oil dose‐ and time‐response effects on cardiac phospholipid fatty acid composition
Authors: Owen Alice J. , Peter‐Przyborowska Beata A. , Hoy Andrew J. , McLennan Peter L.
Published: November 2006

Fish consumption is associated with reduced cardiovascular mortality, and elevated myocardial long‐chain n−3 polyunsaturated FA (PUFA) content is implicated in this cardioprotection. This study examined the dose and time responses for incorporation of n−3 PUFA into cellular membranes in rats fed fish oil (FO)‐containing diets. For the time course study, rats were fed a 10% FO diet for periods ranging from 0 to 42 d, after which myocardial and erythrocyte membrane fatty acid composition was determined. For the dose response study, rats (n=3) were fed 0, 1.25, 2.5, 5, or 10% FO for 4 wk, with myocardial, erythrocyte, and skeletal muscle membrane FA determined. Myocardial DHA (22∶6n−3) levels doubled in 2 d, stabilizing at levels ≈200% higher than control after 28 d feeding with 10% FO. By comparison, DHA levels doubled after 4 wk of 1.25% FO feeding. In myocardium and skeletal muscle, EPA (20∶5n−3) levels remained low, but in erythrocytes EPA levels reached 50% of DHA levels. The n−3 PUFA were incorporated at the expense of n−6 PUFA in myocardium and skeletal muscle, whereas erythrocytes maintained arachidonic acid levels, and total n−3 PUFA incorporation was lower. This study shows that low doses of FO produce marked changes in myocardial DHA levels; maximal incorporation takes up to 28 d to occur; and while erythrocytes are a good indicator of tissue n−3 incorporation in stable diets, they vary greatly in their time course and pattern of incorporation.
Fasting and postprandial lipid response to the consumption of modified milk fats by guinea pigs
Authors: Asselin Geneviève , Lavigne Charles , Bergeron Nathalie , Angers Paul , Belkacemi Khaled , Arul Joseph , Jacques Hélène
Published: November 2006

The objective of the present study was to investigate the effect of three modified milk fats with different melting profiles on fasting and postprandial lipid responses and on fecal fat content in guinea pigs. We hypothesized that the consumption of modified milk fat with a high m.p. results in reduced fasting and postprandial lipid responses compared with that of modified milk fat fractions with lower m.p. To test this hypothesis, male Hartley guinea pigs were fed isoenergetic diets containing 110 g of fat/kg, either from one of the three modified milk fats with high (HMF), medium (MMF), or low melting profiles (LMF), or from one of the two reference fats as whole mil fat (MF) or a fat blend similar to that of nonhydrogenated soft margarine (MA) for 28 d. Food intake (P<0.05) and body weight gain (P<0.05) were reduced in the animals fed the HMF diet compared with the other groups. In the fasting state, plasma LDL cholesterol was highest in animals fed the LMF diet, intermediary in those fed the MMF and MF diets, and lowest in those fed the HMF and MA diets (P<0.05). Postprandially, the areas under the 0‐ to 3‐h curves for the changes in plasma TG were lower in the HMF group than in the MA‐ and LMF‐fed guinea pigs (P<0.05). The fecal fat content was higher (P<0.05) in the HMF group compared to the other milk fat groups. The present results suggest that modified milk fats can impact food intake, body weight gain, fasting cholesterolemia, and postprandial triglyceridemia, and these changes may be attributed to an altered fat absorption.
Effect of temperature on the stereoselectivity of phospholipase D toward glycerol in the transphosphatidylation of phosphatidylcholine to phosphatidylglycerol
Authors: Sato Rina , Itabashi Yutaka , Suzuki Akira , Hatanaka Tadashi , Kuksis Arnis
Published: November 2006

In this study, the effect of temperature on the stereoselectivity of phospholipase D (PLD) toward the two primary hydroxyl groups of glycerol in the transphosphatidylation reaction of phosphatidylcholine to phosphatidylglycerol (PtdGro) was investigated. For this purpose, PLD from bacteria (Streptomyces septatus TH‐2, S. halstedii subsp. scabies K6, and Actinomadura sp.) and cabbage were tested. At the reaction temperatures employed (0–60°C), the proportions of the two PtdGro diastereomers, namely, 1,2‐dioleoyl‐sn‐glycero‐3‐phospho‐3′‐sn‐glycerol (R,R configuration) and 1,2‐dioleoyl‐sn‐glycero‐3‐phosphol‐1′‐sn‐glycerol (R,S configuration), which were produced with PLD from Streptomyces TH‐2 and Actinomadura sp., changed gradually from 50% R,R and 50% R,S at 50–60°C to 70% R,R and 30% R,S at O°C. These alterations suggested that the stereoselectivity of the bacterial PLD toward the two primary hydroxyl groups of prochiral glycerol was significantly influenced by reaction temperature. PLD from Streptomyces K6 showed relatively little effect of temperature on stereoselectivity, giving 65–69% R,R in the temperature range of 60–10°C examined. The plots of In ([R,R]/[R,S]) vs. 1/T gave good linear fits for these three bacterial PLD. No temperature effect was observed for cabbage PLD, which gave an almost equimolar mixture of the R,R and R,S diastereomers in the range from 0 to 40°C. The temperature‐dependent change in enantiomeric selectivity of the bacterial PLD promises potentially profitable commercial exploitation.
A randomized controlled trial of the effect of fish oil supplementation in late pregnancy and early lactation on the n−3 fatty acid content in human breast milk
Authors: Boris Jane , Jensen Benny , Salvig Jannie Dalby , Secher Niels J. , Olsen Sjúrdur F.
Published: November 2006

The aim of this research was to investigate the effect of fish oil supplementation, in the third trimester of pregnancy and early lactation period of healthy pregnant Danish women. Forty‐four pregnant women were randomly allocated to fish oil supplementation (1.3 g EPA and 0.9 g DHA per day) from week 30 of gestation (FO‐group) or to a control regimen (olive oil or no oil; controls). The FO‐group was randomly subdivided into women stopping fish oil supplementation at delivery [FO(pregn)], and women continuing supplementation for an, additional 30 d [FO(pregn/lact)]. Thirty‐six women agreed to collect milk samples at days 4, 16, and 30 postpartum. The FA composition of the milk samples was determined by GLC. At days 4, 16, and 30 in lactation, FO(pregn/lact) women (n=12) had, respectively 2.3 (P=0.001), 4.1 (P=0.001), and 3.3 (P=0.001) times higher mean contents of LCPUFA(n−3) in their breast milk compared with controls (n=13), and 1.7 (P=0.005), 2.8 (P=0.001), and 2.8 (P=0.001), times higher LCPUFA(n−3) contents, respectively, at these days compared with FO(pregn) women (n=11). The latter group did not differ significantly from controls with regard to LCPUFA(n−3) content in the breast milk. Similar results were obtained when analyzing separately for effects on the milk content of DHA. Dietary supplementation with 2.7 g LCPUFA(n−3) per day from week 30 of gestation and onward more than tripled the LCPUFA(n−3) content in early breast milk; supplementation limited to pregnancy only was much less effective.
Quantitative determination of total lipid hydroperoxides by a flow injection analysis system
Authors: Sohn Jeong‐Ho , Taki Yusuke , Ushio Hideki , Ohshima Toshiaki
Published: November 2006

A flow injection analysis (FIA) system coupled with a fluorescence detection system using diphenyl‐1‐pyrenylphosphine (DPPP) was developed as a highly sensitive and reproducible quantitative method of total lipid hydroperoxide analysis. Fluorescence analysis of DPPP oxide generated by the reaction of lipid hydroperoxides with DPPP enabled a quantitative determination of the total amount of lipid hydroperoxides. Use of 1‐myristoyl‐2‐(12‐((7‐nitro‐2‐1,3‐benzoxadiazol‐4‐yl)amino) dodecanoyl)‐sn‐glycero‐3‐phosphocholine as the internal standard improved the sensitivity and reproducibility of the analysis. Several commercially available edible oils, including soybean oil, rapeseed oil, olive oil, corn oil, canola oil, safflower oil, mixed vegetable oils, cod liver oil, and sardine oil were analyzed by the FIA system for the quantitative determination of total lipid hydroperoxides. The minimal amounts of sample oils required were 50 μg of soybean oil (PV=2.71 meq/kg) and 3 mg of sardine oil (PV=0.38 meq/kg) for a single injection. Thus, sensitivity was sufficient for the detection of a small amount and/or low concentration of hydroperoxides in common edible oils. The recovery of sample oils for the FIA system ranged between 87.2±2.6% and 102±5.1% when PV ranged between 0.38 and 58.8 meq/kg. The CV in the analyses of soybean oil (PV=3.25 meq/kg), cod liver oil (PV=6.71 meq/kg), rapeseed oil (PV=12.3 meq/kg), and sardine oil (PV=63.8 meq/kg) were 4.31, 5.66, 8.27, and 11.2%, respectively, demonstrating sufficient reproducibility of the FIA system for the determination of lipid hydroperoxides. The squared correlation (r2) between the FIA system and the official AOCS iodometric titration method in a linear regression analysis was estimated at 0.9976 within the range of 0.35−77.8 meq/kg of PV (n=42). Thus, the FIA system provided satisfactory detection limits, recovery, and reproducibility. The FIA system was further applied to evaluate changes in the total amounts of lipid hydroperoxides in fish muscle stored on ice.
Fatty acid composition of lymphocytes and macrophages from rats fed fiber‐rich diets: A comparison between oat bran‐ and wheat bran‐enriched diets
Authors: Cavaglieri Felippe C. R. , Calder P. C. , Vecchia M. G. , Campos M. R. , Mancini‐Filho J. , Newsholme E. A. , Curi R.
Published: November 2006

The effect of oat bran‐(OBD) and wheat bran‐enriched diets (WBD) on fatty acid composition of neutral lipids and phospholipids of rat lymphocytes and macrophages was investigated. In neutral lipids of lymphocytes, OBD reduced the proportion of palmitoleic acid (48%), whereas WBD reduced by 43% palmitoleic acid and raised oleic (18%), linoleic (52%), and arachidonic (2.5‐fold) acids. In neutral lipids of macrophages, OBD increased palmitic (16%) and linoleic (29%) acids and slightly decreased oleic acid (15%). The effect of WBD, however, was more pronounced: It reduced myristic (60%), stearic (24%) and arachidonic (63%) acids, and it raised palmitic (30%) and linoleic (2.3‐fold) acids. Neither OBD nor WBD modified the composition of fatty acids in phospholipids of lymphocytes. In contrast, both diets had a marked effect on composition of fatty acids in macrophage phospholipids. OBD raised the proportion of myristic (42%) and linoleic (2,4‐fold) acids and decreased that of lauric (31%), palmitoleic (43%), and arachidonic (29%) acids. WBD increased palmitic (18%) and stearic (23%) acids and lowered palmitoleic (35%) and arachidonic (78%) acids. Of both cells, macrophages were more responsive to the effect of the fiber‐rich diets on fatty aicd composition of phospholipids. The high turnover of fatty acids in macrophage membranes may explain the differences between both cells. The modifications observed due to the effects of both diets were similar in few cases: an increase in palmitic and linoleic acids of total neutral lipids occurred and a decrease in palmitoleic and arachidonic acids of phospholipid. Therefore, the mechanism involved in the effect of both diets might be different.
The process management triangle: An empirical investigation of process trade‐offs
Authors: Klassen Robert D. , Menor Larry J.
Published: November 2006

Advancing theory and understanding of process management issues continues to be a central concern for operations management research and practice. While an insightful body of knowledge – based primarily on studies at the process‐level – exists on the management of capacity and inventory, the dynamism characterizing most operating and competitive systems poses an ongoing challenge for managers having to mitigate the impact of variability across different levels of operating systems (e.g., production processes, facilities, and supply chains). This paper builds on a conceptual framework, derived from queuing theory and termed the “process management triangle”, to explore the extent to which fundamental trade‐offs between capacity utilization, variability and inventory (CVI) generalize to complex operations and business systems. To do so, empirical analyses utilizing comparatively unique data for the study of these process management issues – and collected from two distinct, vastly different levels of analysis – are presented. First, a simulation‐based facility‐level analysis using teaching case study data is presented. Second, an industry‐level analysis employing archival economic data spanning three multi‐year periods is considered. Collectively, these empirical analyses provide exploratory support for the generalization and extension of analytical insights on CVI trade‐offs to both complex operations and business systems, although with decreasing explanatory power. The implications of these studies for furthering process management theory and understanding are framed around additional research propositions intended to guide future investigation of CVI trade‐offs.
RWANDA'S GACACA COURTS: A PRELIMINARY CRITIQUE
Authors: KIRKBY COEL
Published: November 2006

Just over a decade after the 1994 genocide, over 1,000 accused languish in Rwandan prisons. The International Criminal Tribunal for Rwanda and the nation's domestic courts have struggled to bring them to trial. In response, the Rwandan government has embarked on an experiment in mass justice: the gacaca courts. The new courts are inspired by traditional dispute resolution mechanisms. The judges are elected by popular vote in their cells to hear cases such as murder, assault and property offences. The system permits appeals (except for property crimes), though not to the domestic courts. The setting is less formal than criminal courts and promotes confessions from perpetrators and forgiveness from survivors. Coupled with this process are two related schemes for victim compensation and community service for those convicted. This article examines these courts from the perspectives of retributive and restorative justice, within the Rwandan context. In practice, the gacaca courts embody both principles, as well as their tension. The judges are lay persons, yet are engaged in complex legal adjudication. The accused have no right to legal representation, nor an appeal to the domestic courts. More importantly, survivors are marginalized by the process as the practical and political pressures on the Rwandan government have made them opt for expediency (more and faster trials) over reconciliation (survivor compensation and manifest regret by the perpetrators). The gacaca courts hold out much promise of reconciling a deeply divided society, but redressing the needs of victims must become a priority.
The aeolian flux of calcium, chloride and nitrate to the McMurdo Dry Valleys landscape: evidence from snow pit analysis
Authors: Witherow Rebecca A. , Lyons W. Berry , Bertler Nancy A.N. , Welch Kathleen A. , Mayewski Paul A. , Sneed Sharon B. , Nylen Thomas , Handley Michael J. , Fountain Andrew
Published: November 2006

We have determined the flux of calcium, chloride and nitrate to the McMurdo Dry Valleys region by analysing snow pits for their chemical composition and their snow accumulation using multiple records spanning up to 48 years. The fluxes demonstrate patterns related to elevation and proximity to the ocean. In general, there is a strong relationship between the nitrate flux and snow accumulation, indicating that precipitation rates may have a great influence over the nitrogen concentrations in the soils of the valleys. Aeolian dust transport plays an important role in the deposition of some elements (e.g. Ca2+) into the McMurdo Dry Valleys' soils. Because of the antiquity of some of the soil surfaces in the McMurdo Dry Valleys regions, the accumulated atmospheric flux of salts to the soils has important ecological consequences. Although precipitation may be an important mechanism of salt deposition to the McMurdo Dry Valley surfaces, it is poorly understood because of difficulties in measurement and high losses from sublimation.
Resistente Anämie bei resistentem Patienten
Authors: Bär  , Keller  , von Garnier  , Kummer
Published: November 2006

Ein 93-jähriger Patient mit transfusionsbedürftiger Blutungsanämie, welche am ehesten im Rahmen einer gastrointestinalen Blutung interpretiert werden konnte, verweigerte weitere diagnostische und therapeutische Abklärungen – mit Ausnahme der Bluttransfusionen. Somit erfolgte innerhalb eines halben Jahres eine Substitution von insgesamt 48 Erythrozytenkonzentraten ohne neue oder diagnostische Erkenntnisse. Zur Diskussion für die zukünftige Behandlungsstrategie beim Patienten wurde die Problematik der Ethikkommission beider Basel EKBBU vorgestellt.
Examination of systematic mislocation of South Sandwich Islands earthquakes using station pairs: Implications for inner core rotation
Authors: Sun Xinlei , Poupinet Georges , Song Xiaodong
Published: November 2006

One of the most robust observations for the inner core rotation is that the differential PKP BC‐DF traveltimes from South Sandwich Islands (SSI) earthquakes to College, Alaska (and some other stations in Alaska), have increased systematically over the past 50 years. The time shift in the differential time residuals is some 0.3 s over 30 years. This temporal change is thought to result from a shift of the inner core structure from a superrotation of the inner core. However, the observation has been hotly debated and has been suggested to be an artifact of systematic earthquake mislocation. Here we examine this issue using three mutually independent approaches, with a goal to quantify the amount of the systematic mislocation, if any. All three approaches involve differencing data between north stations at a similar azimuth as the SSI‐Alaska azimuth and south stations at nearly the opposite azimuth. Mislocation along this azimuth has greatest impact on the PKP differential times. In approach 1, we examine how the double difference of P traveltimes between a north station and a south station changes with time. Because the differential apparent slowness between the P traveltimes of the pairs is 8 to 16 times that of the differential BC‐DF times, mislocation would cause a time shift in the double difference an order of magnitude larger than that of BC‐DF times. In approach 2, we compare directly difference in P arrival times between two SSI events that are close by and between a north and a south stations, which avoids using earthquake locations and Earth models entirely. In approach 3, we compare PKP traveltime residuals between a group of north and south stations. Because PKP traveltimes are generally not used for location in earthquake bulletins, they provide an independent data set to check earthquake location errors. The results from approaches 1 and 2, both of which use P data, are generally consistent. The mislocation is up to 3.6 ± 4.2 km (one standard deviation), explaining less than 10% of the observed COL temporal change. The results from approach 3 using PKP data show a larger mislocation but with a larger error (14.4 ± 10.8 km over 30 years). It can explain about 30% ± 22% of the observed COL temporal change. Therefore inner‐core superrotation is still the best explanation for the observed temporal change in the differential traveltimes.
Evaluation of Global Ozone Monitoring Experiment (GOME) ozone profiles from nine different algorithms
Authors: Meijer Y. J. , Swart D. P. J. , Baier F. , Bhartia P. K. , Bodeker G. E. , Casadio S. , Chance K. , Del Frate F. , Erbertseder T. , Felder M. D. , Flynn L. E. , Godin‐Beekmann S. , Hansen G. , Hasekamp O. P. , Kaifel A. , Kelder H. M. , Kerridge B. J. , Lambert J.‐C. , Landgraf J. , Latter B. , Liu X. , McDermid I. S. , Pachepsky Y. , Rozanov V. , Siddans R. , Tellmann S. , van der A R. J. , van Oss R. F. , Weber M. , Zehner C.
Published: November 2006

An evaluation is made of ozone profiles retrieved from measurements of the nadir‐viewing Global Ozone Monitoring Experiment (GOME) instrument. Currently, four different approaches are used to retrieve ozone profile information from GOME measurements, which differ in the use of external information and a priori constraints. In total nine different algorithms will be evaluated exploiting the optimal estimation (Royal Netherlands Meteorological Institute, Rutherford Appleton Laboratory, University of Bremen, National Oceanic and Atmospheric Administration, Smithsonian Astrophysical Observatory), Phillips‐Tikhonov regularization (Space Research Organization Netherlands), neural network (Center for Solar Energy and Hydrogen Research, Tor Vergata University), and data assimilation (German Aerospace Center) approaches. Analysis tools are used to interpret data sets that provide averaging kernels. In the interpretation of these data, the focus is on the vertical resolution, the indicative altitude of the retrieved value, and the fraction of a priori information. The evaluation is completed with a comparison of the results to lidar data from the Network for Detection of Stratospheric Change stations in Andoya (Norway), Observatoire Haute Provence (France), Mauna Loa (Hawaii), Lauder (New Zealand), and Dumont d'Urville (Antarctic) for the years 1997–1999. In total, the comparison involves nearly 1000 ozone profiles and allows the analysis of GOME data measured in different global regions and hence observational circumstances. The main conclusion of this paper is that unambiguous information on the ozone profile can at best be retrieved in the altitude range 15–48 km with a vertical resolution of 10 to 15 km, precision of 5–10%, and a bias up to 5% or 20% depending on the success of recalibration of the input spectra. The sensitivity of retrievals to ozone at lower altitudes varies from scheme to scheme and includes significant influence from a priori assumptions.
Modeling the catchment via mixtures: Issues of model specification and validation
Authors: Marshall Lucy , Sharma Ashish , Nott David
Published: November 2006

One way to reduce predictive uncertainty due to the model structure is to incorporate information from several different models at once. Model aggregation can lead to a better prediction than a single model structure, as each model provides new information about the processes that are occurring. This paper presents an alternative by further developing an idea introduced by Marshall et al. (2006). A modeling framework that combines a number of individual model structures is presented. The approach, known as the hierarchical mixtures of experts (HME) framework, allows for a more sophisticated method of model aggregation by allowing individual models to be selected based on the preceding catchment conditions and also gives greater flexibility to the specification of the model errors. The modeling framework was previously shown to have potential as a modeling tool for assessing model components and identifying structural deficiencies in existing representations. This paper presents a basis for using the HME rainfall‐runoff modeling framework for prediction or simulation. We illustrate the rationale behind the proposed framework using daily rainfall, evapotranspiration, and flow data from two small sized catchments (<150 km2) in the state of New South Wales, Australia. Two different forms of a conceptual rainfall‐runoff model are used to represent the multiple component models of the framework. We investigate the usefulness of different catchment predictors to weight the individual models by assessing the resulting performance in a predictive sense. The usefulness of alternative models for the description of the model errors is shown. The study shows that given careful comparison of the possible mechanisms related to a switch in the catchment “state,” the proposed approach can be a useful predictive tool, giving an aggregated model simulation that is better than any individual model.
Large‐scale climatic patterns control large lightning fire occurrence in Canada and Alaska forest regions
Authors: Macias Fauria Marc , Johnson Edward A.
Published: November 2006

Large lightning wildfires in Canada and Alaska account for most of the area burnt and are main determiners of the age mosaic of the landscape. Such fires occur when positive midtroposphere height anomalies persist > 10 days during the fire season. Midtroposphere anomalies are part of teleconnections which are created by atmospheric and coupled sea/air dynamics. Large lightning fire occurrence and area burnt data were used to define eight centers of large wildfire variability in Canada and Alaska during 1959–1999. Preferred positions of persistent positive midtroposphere anomalies correlated with the Fire Regions during large fire events. Active fire weather showed strong relations with Pacific Decadal Oscillation (PDO) at interdecadal timescales and with El Niño Southern Oscillation (ENSO) and Arctic Oscillation (AO) mostly at interannual (2 to 6 years) timescales. PDO and ENSO (AO) related large fires were more frequent in the western (eastern) regions. The mountain ranges in western Canada play a major role in the large‐scale patterns of large fire occurrence through retention of PDO‐related Pacific Ocean moisture, causing the dynamics of large fires each side of the ranges to be mostly in antiphase. The PDO/ENSO regime shift of 1976/1977, together with the strong and persistent positive phase of AO during the late 1980s and 1990s contributed to the increase in area burned in the study area except in British Columbia and Alaska. PDO‐ENSO‐AO interactions with active fire weather provide an explanation for changes in large fire occurrence frequency during the last centuries in the area.
Isotopic assessment of NO3− and SO42− mobility during winter in two adjacent watersheds in the Adirondack Mountains, New York
Authors: Campbell John L. , Mitchell Myron J. , Mayer Bernhard
Published: November 2006

Biogeochemical cycling of N and S was examined at two watersheds in the Adirondack Mountains, New York, to better understand the retention and loss of these elements during winter and spring snowmelt. We analyzed stable isotope compositions of NO3− (δ15N‐NO3−, δ18O‐NO3−) and SO42− (δ34S‐SO42−, δ18O‐SO42−), along with concentrations and fluxes of NO3− and SO42−, in precipitation, throughfall, snowpack, snowmelt, soil water, groundwater, and stream water. Isotopic results showed no evidence of NO3− and SO42− transformations in the forest canopy and snowpack; however, markedly decreased δ18O values of NO3− and SO42− in forest floor water suggest that microbial processing occurred in organic soil horizons. Similarly low δ18O values of NO3− and SO42− were observed in forest floor and mineral soil leachates, groundwater, and streams. Over the winter observation period, most of the NO3− and SO42− in stream water was from a watershed‐derived source, whereas atmospheric contributions were relatively minor. Despite differences in soil water NO3− concentrations between watersheds, the isotopic composition of NO3− (δ15N‐NO3−, δ18O‐NO3−) was similar, and indicated that in both watersheds most of the NO3− was produced by nitrification in the forest soils. Although there was likely some contribution of SO42− from microbial oxidation of carbon‐bonded sulfur, most of the stream water SO42− appeared to be derived from weathering of S‐containing bedrock or parent material. The decreased δ18O values of NO3− and SO42− in upper soil horizons indicate that atmospheric deposition of N and S was not directly linked with stream water losses, even during winter and spring snowmelt.
STAT5 proteins are involved in down-regulation of iron regulatory protein 1 gene expression by nitric oxide
Authors: Starzynski Rafal Radoslaw , Gonçalves Ana Sofia , Muzeau Françoise , Tyrolczyk Zofia , Smuda Ewa , Drapier Jean-Claude , Beaumont Carole , Lipinski Pawel
Published: November 2006

RNA-binding activity of IRP1 (iron regulatory protein 1) is regulated by the insertion/extrusion of a [4Fe-4S] cluster into/from the IRP1 molecule. NO (nitic oxide), whose ability to activate IRP1 by removing its [4Fe-4S] cluster is well known, has also been shown to down-regulate expression of the IRP1 gene. In the present study, we examine whether this regulation occurs at the transcriptional level. Analysis of the mouse IRP1 promoter sequence revealed two conserved putative binding sites for transcription factor(s) regulated by NO and/or changes in intracellular iron level: Sp1 (promoter-selective transcription factor 1) and MTF1 (metal transcription factor 1), plus GAS (interferon-γ-activated sequence), a binding site for STAT (signal transducer and activator of transcription) proteins. In order to define the functional activity of these sequences, reporter constructs were generated through the insertion of overlapping fragments of the mouse IRP1 promoter upstream of the luciferase gene. Transient expression assays following transfection of HuH7 cells with these plasmids revealed that while both the Sp1 and GAS sequences are involved in basal transcriptional activity of the IRP1 promoter, the role of the latter is predominant. Analysis of protein binding to these sequences in EMSAs (electrophoretic mobility-shift assays) using nuclear extracts from mouse RAW 264.7 macrophages stimulated to synthesize NO showed a significant decrease in the formation of Sp1–DNA and STAT–DNA complexes, compared with controls. We have also demonstrated that the GAS sequence is involved in NO-dependent down-regulation of IRP1 transcription. Further analysis revealed that levels of STAT5a and STAT5b in the nucleus and cytosol of NO-producing macrophages are substantially lower than in control cells. These findings provide evidence that STAT5 proteins play a role in NO-mediated down-regulation of IRP1 gene expression.
Quantification of polarized trafficking of transferrin and comparison with bulk membrane transport in hepatic cells
Authors: Wüstner Daniel
Published: November 2006

Transport of the recycling marker transferrin was analysed in polarized hepatic HepG2 cells using quantitative fluorescence microscopy and mathematical modelling. A detailed map and kinetic model for transport of transferrin in hepatic cells was developed. Fluorescent transferrin was found to be transported sequentially through basolateral SE (sorting endosomes) to a SAC/ARC (subapical compartment/apical recycling compartment). DiI (di-indocarbocyanine) lipid probes of different acyl chain length (DiIC12 and DiIC16) co-localized with transferrin in basolateral SE and in the SAC/ARC. By kinetic comparison of hepatic transport of transferrin and labelled HDL (high-density lipoprotein), it is shown that transport of transferrin from SE to the SAC/ARC follows a default pathway together with HDL. Kinetic modelling of fluorescence data provides an identical half-time for SE-to-SAC/ARC transport of transferrin and fluorescent HDL (t½=4.2 min). Fluorescent transferrin was found to recycle with a half-time of t½=12.9 min from the SAC/ARC to the basolateral cell surface of HepG2 cells. In contrast with HDL, targeting of labelled transferrin from the SAC/ARC to the apical biliary canaliculus was negligible. The results indicate that transport from basolateral hepatic SE to the SAC/ARC represents a bulk flow process and that polarized sorting occurs mainly at the level of the SAC/ARC.
NF-Y, AP2, Nrf1 and Sp1 regulate the fragile X-related gene 2 (FXR2)
Authors: Mahishi Lata , Usdin Karen
Published: November 2006

Fragile X syndrome, the most common heritable form of mental retardation, is caused by silencing of the FMR1 (fragile X mental retardation-1 gene). The protein product of this gene, FMRP (fragile X mental retardation protein), is thought to be involved in the translational regulation of mRNAs important for learning and memory. In mammals, there are two homologues of FMRP, namely FXR1P (fragile X-related protein 1) and FXR2P. Disruption of Fxr2 in mice produces learning and memory deficits, and Fmr1 and Fxr2 double-knockout mice have exaggerated impairments in certain neurobehavioral phenotypes relative to the single gene knockouts. This has led to the suggestion that FMR1 and FXR2 functionally overlap and that increasing the expression of FXR2P may ameliorate the symptoms of an FMRP deficiency. Interestingly, the region upstream of the FXR2 translation start site acts as a bidirectional promoter in rodents, driving transcription of an alternative transcript encoding the ABP (androgen-binding protein) [aABP (alternative ABP promoter)]. To understand the regulation of the human FXR2 gene, we cloned the evolutionarily conserved region upstream of the FXR2 translation start site and showed that it also has bidirectional promoter activity in both neuronal and muscle cells as evidenced by luciferase reporter assay studies. Alignment of the human, mouse, rat, rabbit and dog promoters reveals several highly conserved transcription factor-binding sites. Gel electrophoretic mobility-shift assays, chromatin immunoprecipitation studies and co-transfection experiments with plasmids expressing these transcription factors or dominant-negative versions of these factors showed that NF-YA (nuclear transcription factor Yα), AP2 (activator protein 2), Nrf1 (nuclear respiratory factor/α-Pal) and Sp1 (specificity protein 1) all bind to the FXR2 promoter both in vitro and in vivo and positively regulate the FXR2 promoter.
High frequency characteristics of FeCoN thin films fabricated by sputtering at various (Ar+N2) gas flow rates
Authors: Liu Yan , Liu Z. W. , Tan C. Y. , Ong C. K.
Published: November 2006

FeCoN soft magnetic thin films with various nitrogen contents were fabricated by varying the gas flow rates of the argon and nitrogen gas mixture used during reactive rf magnetron sputtering. It was found that the resistivity of FeCoN film increased up to 211 μΩ cm with increasing nitrogen content. The film produced at the gas flow rate of 7 sccm exhibited the best soft magnetic properties with small coercivity and relatively large saturation magnetization. The microstructure of the films was examined by high-resolution transmission electron microscopy and α″-FeCo phase with very high saturation magnetization was observed in the films. The high-frequency properties of the FeCoN thin films were experimentally characterized and theoretically examined. The Hoffmann’s ripple theory was used to explain the permeability spectra for the films with strong magnetization dispersion. We found that the ripple effect is responsible for the large damping in the films, and those films with larger coercivities have stronger magnetization dispersion. With the gas flow rate of the argon and nitrogen gas mixture increasing from 0 to 15 sccm, the low-frequency permeability decreased from 680 to 245 and the ferromagnetic resonance frequency increased from 2.09 to 2.99 GHz.