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Selected AbstractsAlcohol is the Main Factor in Excess Traffic Accident Fatalities in FranceALCOHOLISM, Issue 12 2002Michel Reynaud Background The aim of this study was to better evaluate the role of alcohol drinking in fatalities linked to road traffic accidents. Methods The data of accidents were collected by a French official agency from police records, including many variables, among which was a blood alcohol test. They were analyzed in a descriptive way and toward a logistic regression. This exhaustive database comprised all of the 500,961 accidents with casualties that involved less than three vehicles (28,506 fatal accidents) recorded in France during a 52 month period (September 1995 to December 1999). The results of the alcohol tests were known in 78.7 of the drivers. Results The blood alcohol concentration was over the legal limit (0.50 g/L in France) in 9.8% of the accidents with casualties overall. Considering only fatal accidents, the rate of positive alcohol test in drivers was approximately 31.5%. This rate varied depending on the period and the type of accident, raising up to 71.2% in single-vehicle accidents (loss of control) at night during the weekend. The percentage of positive alcohol tests also dramatically increased following the number of fatalities per accident (87.5% in single-vehicle accidents during weekend nights involving three or more killed). The logistic regression in single-vehicle accident shows that the higher odds ratios concern the positive blood alcohol test (OR = 4.19), clearly overwhelming the other precipitating factors of accidents (age of driver, meteorological conditions, time of day, and other factors). Conclusions Drinking alcohol before driving is a well known factor of accidents. We clearly demonstrate here that it is the main factor leading to deaths linked to road traffic accidents in France. The results are strengthened, and some analyses are allowed, by the exceptional features of our database. The authors emphasize the need for prevention measures. [source] An upscaling method and a numerical analysis of swelling/shrinking processes in a compacted bentonite/sand mixtureINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 15 2004M. Xie Abstract This paper presents an upscaling concept of swelling/shrinking processes of a compacted bentonite/sand mixture, which also applies to swelling of porous media in general. A constitutive approach for highly compacted bentonite/sand mixture is developed accordingly. The concept is based on the diffuse double layer theory and connects microstructural properties of the bentonite as well as chemical properties of the pore fluid with swelling potential. Main factors influencing the swelling potential of bentonite, i.e. variation of water content, dry density, chemical composition of pore fluid, as well as the microstructures and the amount of swelling minerals are taken into account. According to the proposed model, porosity is divided into interparticle and interlayer porosity. Swelling is the potential of interlayer porosity increase, which reveals itself as volume change in the case of free expansion, or turns to be swelling pressure in the case of constrained swelling. The constitutive equations for swelling/shrinking are implemented in the software GeoSys/RockFlow as a new chemo-hydro-mechanical model, which is able to simulate isothermal multiphase flow in bentonite. Details of the mathematical and numerical multiphase flow formulations, as well as the code implementation are described. The proposed model is verified using experimental data of tests on a highly compacted bentonite/sand mixture. Comparison of the 1D modelling results with the experimental data evidences the capability of the proposed model to satisfactorily predict free swelling of the material under investigation. Copyright © 2004 John Wiley & Sons, Ltd. [source] Fundus rotation gastroplasty: rationale, technique and results,DISEASES OF THE ESOPHAGUS, Issue 2 2002W. Uhl SUMMARY. Anastomotic leakage is the main factor (up to 30%) for postoperative morbidity and mortality after esophageal resection. Compromised anastomotic perfusion after dissection of supplying vessels for gastric tube formation and tension on the suture line are the two main reasons for anastomotic insufficiency. To prevent anastomotic leakage, a new technique for gastric tube formation after esophageal resection has been developed and introduced into surgical practice: the fundus rotation gastroplasty (FRG). The following paper summarizes rationale, technique and early results of this new technique. It is shown that the FRG is a safe and effective technique for esophageal reconstruction and offers important advantages over conventional gastroplasties: (i) the improved perfusion of the oral part of the tube; (ii) the gain of tube length allowing for a safer performance of even pharyngeal anastomosis as shown by the low insufficiency rate of 9%; and (iii) the increase of remaining gastric reservoir supporting physiologic stomach and gut function. Therefore, the FRG seems to be an alternative and safe method for esophageal reconstruction, especially for high anastomotic locations. [source] Spatial Association in a Highly Inbred Ungulate Population: Evidence of Fine-Scale Kin RecognitionETHOLOGY, Issue 2 2008Jorge Cassinello We present the first evidence of fine-scale kin recognition, based on a continuous measure of relatedness, in ungulates. The spatial association between herdmates of a captive population of aoudad (Ammotragus lervia), where all the individuals are related, is analysed during resting time. Our goal was to estimate which factors influence individuals' associations. The study population is highly inbred, although it does not show serious deleterious effects caused by consanguinity. It comprises a single captive herd, reproducing freely and in good conditions for more than 10 yr. It emerges that kin, measured as the coefficient of relationship between two given herdmates, is the main factor determining the spatial association (e.g. average distance) of male,male and female,female dyads, as more-related individuals tend to rest closer to each other than less-related ones. As for male,female dyads, individuals of a similar age tend to stay closer. To rule out any familiarity confounding effects, individuals' cohabitation time in the herd was added as a random factor in the analyses. Concerning the type of dyad, mother,calf dyads are characterized by higher proximity than others, particularly during the suckling period, whereas males tend to stay closer to each other than females or male,female dyads, being also more kin-related. Female social rank does not influence spatial association between herdmates. These results are related to group composition of the species in the wild, which are characterized by intense mother,calf bonds and all-male groups that are probably kin-related. It is seen that adult male,female associations are not related to kinship, but to age similarity, which is in accord with the assumption that main family groups in the wild are formed by matrilineal lines, whereas males are the dispersing sex. [source] Anion-Dependent Structural Diversity in Silver(I) Complexes of 4-Amino-3,5-diisopropyl-1,2,4-triazoleEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 5 2007Guang Yang Abstract Reactions of silver salts with 4-amino-3,5-diisopropyl-1,2,4-triazole (L) afford dinuclear complex [Ag2L2(NO3)2(CH3CN)], triangular complex [Ag3L3](CF3SO3)3, and cyclic tetranuclear complexes [Ag4L6](BF4)4 and [Ag4L6](ClO4)4. On the basis of the X-ray analyses, anions are found to play an important role in determining the structures. Through coordination/noncoordination, anions can impart their influence on the coordination geometry of Ag atoms and the angles of N,Ag,N, which seems to be the main factor controlling the nuclearity of the reaction products in this system. 1H NMR and MS measurements suggest that these complexes probably retain their structural integrities in CH3CN solution. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Drug/substance reversal effects of a novel tri-substituted benzoflavone moiety (BZF) isolated from Passiflora incarnata Linn.,a brief perspectiveADDICTION BIOLOGY, Issue 4 2003Kamaldeep Dhawan The present work is a mini-review of the author's original work on the plant Passiflora incarnata Linn., which is used in several parts of the world as a traditional medicine for the management of anxiety, insomnia, epilepsy and morphine addiction. A tri-substituted benzoflavone moiety (BZF) has been isolated from the bioactive methanol extract of this plant, which has been proposed in the author's earlier work to be responsible for the biological activities of this plant. The BZF moiety has exhibited significantly encouraging results in the reversal of tolerance and dependence of several addiction-prone psychotropic drugs, including morphine, nicotine, ethanol, diazepam and delta-9-tetrahydrocannabinol, during earlier pharmacological studies conducted by the author. In addition to this, the BZF moiety has exhibited aphrodisiac, libido-enhancing and virility-enhancing properties in 2-year-old male rats. When administered concomitantly with nicotine, ethanol and delta-9-tetrahydrocannabinol for 30 days in male rats, the BZF also prevented the drug-induced decline in sexuality in male rats. Because the BZF moiety isolated from P. incarnata is a tri-substituted derivative of alpha-naphthoflavone (7,8-benzoflavone), a well-known aromatase-enzyme inhibitor, the mode of action of BZF has been postulated to be a neurosteroidal mechanism vide in which the BZF moiety prevents the metabolic degradation of testosterone and upregulates blood-testosterone levels in the body. As several flavonoids (e.g. chrysin, apigenin) and other phytoconstituents also possess aromatase-inhibiting properties, and the IC 50 value of such phytomoieties is the main factor determining their biochemical efficacy, by altering their chemical structures to attain a desirable IC 50 value new insights in medical therapeutics can be attained, keeping in view the menace of drug abuse worldwide. [source] RELATIVE ROLE OF GENETIC DETERMINATION AND PLASTIC RESPONSE DURING ONTOGENY FOR SHELL-SHAPE TRAITS SUBJECTED TO DIVERSIFYING SELECTIONEVOLUTION, Issue 5 2009Paula Conde-Padín We studied the relative role of genetic determination versus plastic response for traits involved in ecological adaptation of two ecotypes of Littorina saxatilis living at different shore levels. To investigate the magnitude of the plastic response across ontogeny, we compared morphological data from individuals grown in the laboratory and taken from the wild at three developmental stages: shelled embryos, juveniles, and adults. The results indicate that most shell shape variation (72,99%) in adaptive traits (globosity and aperture of the shell) is explained by the ecotype irrespective of the growth environment, suggesting that direct genetic determination is the main factor responsible for the process of adaptation in the wild. There was a tendency for the contribution of plasticity to increase over ontogeny but, in general, the direction of the plastic response did not suggest that this was adaptive. [source] Screening of urocanic acid isomers in human basal and squamous cell carcinoma tumors compared with tumor periphery and healthy skinEXPERIMENTAL DERMATOLOGY, Issue 10 2008Juan Manuel Decara Abstract:,Trans -urocanic acid is a major chromophore for ultraviolet (UV) radiation in human epidermis. The UV induces photoisomerization of trans -urocanic acid (tUCA) form to cis -urocanic acid (cUCA) and has been reported as an important mediator in the immunosuppression induced by UV. This immunomodulation has been recognized as an important factor related to skin cancer development. This is the first time that UCA isomers have been measured in epidermis of skin biopsies from patients with squamous cell carcinoma (SCC) and with basal cell carcinoma (BCC) and compared with the tumor periphery and biopsies of healthy photoexposed and non-photoexposed skin as controls. The UCA isomers were separated and quantified by high performance liquid chromatography. Analysis of UCA in healthy skin showed significant increase in total UCA content in non-photoexposed body sites compared with highly exposed skins. In contrast, the percentage of cUCA was higher in photoexposed body sites. Maximal levels of cUCA were found in cheek, forehead and forearm and lower levels in abdomen and thigh. No differences were found in total UCA concentration between the tumor samples and healthy photoexposed skin. However, differences were found in relation between isomers. Higher levels of cUCA were detected in SCC biopsies (44% of total UCA) compared with samples of BCC and that of healthy photoexposed skin (30%). These results suggest that the UV radiation exposure, a main factor in development of SCC can be mediated, apart from direct effect to cells (DNA damage), by immunosuppression pathways mediated by high production of cUCA. [source] The dispersal and deposition of hydrochorous plant seeds in drainage ditchesFRESHWATER BIOLOGY, Issue 10 2010HESTER SOOMERS Summary 1. Surface water is an important dispersal vector for wetland plant species. However, most previous studies on hydrochory (i.e. water dispersal) have focused on ecosystems with relatively rapid water flow. Therefore, there is a need to study such dispersal in slow-flowing or stagnant waterbodies, such as drainage ditches, which might act as dispersal corridors between habitat patches. 2. To gain insight into the mechanisms by which seeds are transported in drainage ditches, the effect of the velocity of wind and water on the rate of transport of floating seeds of three wetland species (Carex pseudocyperus L., Iris pseudacorus L. and Sparganium erectum L.) was investigated. Furthermore, in release and retrace experiments with painted C. pseudocyperus seeds, a number of factors potentially determining the probability of seed deposition were investigated. 3. Net wind speed was found to be the main factor determining the rate at which seeds are transported in drainage ditches. No relation between water flow at middepth in the ditches and seed transport was found. Wind speed and flow at the water surface were positively related. The effect of wind speed on the rate of transport of floating seeds was greater for S. erectum seeds, because a greater ratio of their volume protrudes from the water, than for C. pseudocyperus and I. pseudacorus seeds. 4. The principal factors that determine seed deposition were aquatic plant cover, ditch slope and indentations in the ditch bank. Seeds changed direction if the wind direction changed, or if there was a bend in the ditch. The final pattern of deposition was related to mean net wind speed. Mean transport distance after 2 days varied between 34 and 451 m. 5. Unlike in rivers, seed transport in ditches was determined by wind speed and direction, enabling multidirectional seed dispersal. We conclude that in slow-flowing waters, wind is a more important driver for hydrochorous seed transport than the flow of water. This sheds a new light on hydrochory and has important consequences for the management of otherwise fragmented wetland remnants. [source] Incorporating life histories and diet quality in stable isotope interpretations of crustacean zooplanktonFRESHWATER BIOLOGY, Issue 7 2008MARC VENTURA Summary 1. Stable isotope studies have been extremely useful for improving general food web descriptions due to their ability to simultaneously summarize complex trophic networks and track the energy flow through them. However, when considering trophic relationships involving only two or few species, application of general isotopic interpretations based on average fractionation values may easily lead to misleading conclusions. In these cases a more accurate consideration of the current processes involved in the isotopic fractionation should be considered. 2. We investigated the trophic relationships of the crustacean zooplankton assemblage in an alpine lake (Lake Redon, Pyrenees) by means of stable isotopes of carbon and nitrogen and applied information on their life history and biochemical composition in the interpretation. 3. The three species occurring in the lake had distinct isotopic signatures: the two copepod species (the cyclopoid Cyclops abyssorum and the calanoid Diaptomus cyaneus) had higher nitrogen isotopic composition than the cladoceran (Daphnia pulicaria), indicative of a higher trophic position of the two copepods. Most intra-specific isotopic variability was associated with growth, while the effect of metabolic turnover was negligible. The effects of changes in the proportion of lipids was restricted to the adults of the two copepods. 4. Daphnia Juveniles showed ontogenetic shifts in their carbon, and nitrogen isotopic composition. Cyclops copepodites only showed changes in carbon isotopic composition. These isotopic shifts with changes in size were the result of: (i) the prevalence of growth over metabolic turnover as the main factor for isotopic variability and (ii) feeding, during the growth period, on isotopically depleted food in the case of Daphnia, and on isotopically enriched food in the case of Cyclops. 5. The carbon isotopic variation in Cyclops juveniles could be explained by fitting an isotopic growth model that considered that they fed entirely on Daphnia. However this was not the case for nitrogen isotopic variability. Cyclops nitrogen isotopic composition variation and the Cyclops to Daphnia nitrogen isotopic enrichment were closely correlated to the quantity of Daphnia protein and to the dissimilarity in the essential amino acid composition between the two species, which can be interpreted as an indication of consumer nitrogen limitation. [source] Habitat selection and diel distribution of the crustacean zooplankton from a shallow Mediterranean lake during the turbid and clear water phasesFRESHWATER BIOLOGY, Issue 3 2007BRUNO B. CASTRO Summary 1. The fish fauna of many shallow Mediterranean Lakes is dominated by small-bodied exotic omnivores, with potential implications for fish,zooplankton interactions still largely unknown. Here we studied diel variation in the vertical and horizontal distribution of the crustacean plankton in Lake Vela, a shallow polymictic and eutrophic lake. Diel sampling was carried out on three consecutive days along a horizontal transect, including an open-water station and a macrophyte (Nymphaea alba) bed. Since transparency is a key determinant of the predation risk posed by fish, the zooplankton sampling campaigns were conducted in both the turbid (autumn) and clear water (spring) phases. 2. In the turbid phase, most taxa were homogeneously distributed along the vertical and horizontal axes in the three consecutive days. The only exception was for copepod nauplii, which showed vertical heterogeneity, possibly as a response to invertebrate predators. 3. In the clear water phase, most zooplankton taxa displayed habitat selection. Vertically, the general response consisted of a daily vertical migration (DVM), despite the limited depth (1.6 m). Horizontally, zooplankters showed an overall preference for the pelagic zone, independent of the time of the day. Such evidence is contrary to the postulated role of macrophytes as an anti-predator refuge for the zooplankton. 4. These vertical (DVM) and horizontal (macrophyte-avoidance) patterns were particularly conspicuous for large Daphnia, suggesting that predation risk from size-selective predators (fish) was the main factor behind the spatial heterogeneity of zooplankton in the spring. Thus, the difference in the zooplankton spatial distribution pattern and habitat selection among seasons (turbid and clear water phases) seems to be mediated the predation risk from fish, which is directly related to water transparency. 5. The zooplankton in Lake Vela have anti-predator behaviour that minimises predation from fish. We hypothesise that, due to the distinct fish community of shallow Mediterranean lakes, aquatic macrophytes may not provide adequate refuge to zooplankters, as seen in northern temperate lakes. [source] Dispersal of adult aquatic Chironomidae (Diptera) in agricultural landscapesFRESHWATER BIOLOGY, Issue 3 2000Yannick R. Delettre SUMMARY 1This study investigates the possible influence of terrestrial landscape structure on the spatial distribution of adult Chironomidae emerging from water bodies in three agricultural areas, each with hedgerow networks, in Brittany (France). 2Using spatially explicit data from 128 yellow pan traps set in pairs at the bottom of hedges throughout the three study areas, we show that landscape structure and heterogeneity must be considered at two different spatial scales. 3At a global scale, distance to water bodies was the main factor explaining the spatial distribution of adult chironomids: both species richness and abundance changed beyond a critical distance to the stream, resulting in different species assemblages of flying insects. 4At a local scale, the abundance of species and individuals at rest in hedges changed with the quality of the hedge (mainly determined by canopy width and cover of the different vegetation layers). 5The density of the hedgerow network, and landscape openness, both influenced the dispersal of chironomid species from water bodies. 6This study, which provides the first estimate of the dispersal capabilities of chironomids in particular landscapes, suggests that the terrestrial environment is an essential component of population dynamics and community structure in aquatic Chironomidae. [source] Hypothyroidism and acquired von Willebrand's syndrome: a systematic reviewHAEMOPHILIA, Issue 3 2008E. MANFREDI Summary., Acquired von Willebrand's syndrome type I is the supposed main underlying cause of bleeding tendency in hypothyroid patients. The purpose of this systematic review was to summarize the published evidence on the association between hypothyroidism and acquired von Willebrand's syndrome. All published clinical epidemiological and interventional studies, case reports and in vitro studies that investigated the association between hypothyroidism and acquired von Willebrand's syndrome were identified by a computer-assisted search of the MEDLINE and EMBASE electronic databases. A quality assessment was performed for clinical epidemiological studies. A total of 41 papers were included. A total of 22 epidemiological in vivo studies, two in vitro studies and 47 case reports were finally analyzed. No high quality in vivo study was identified. Almost all bleeding episodes described in the case reports were mucocutaneous. von Willebrand factor (VWF) antigen value was available for 23 patients: median value 28 U/dL (range: 4,45); VWF activity was available for 24 patients: median value 28.5 U/dL (range: <3,55); factor VIII activity was available for 16 patients: median value 47 U/dL (range: 9,74). Acquired von Willebrand's syndrome may be the main factor responsible for bleeding diathesis in overt hypothyroid patients. Even if bleeding episodes are mainly mild and mucocutaneous, blood transfusion, drug administration or surgical procedure may be required. [source] Stromal cells promote bone invasion by suppressing bone formation in ameloblastomaHISTOPATHOLOGY, Issue 4 2008G S A Sathi Aims:, To study the stromal variation and role of stromal,tumour cell interaction in impaired bone formation as well as enhanced bone resorption in ameloblastoma. Methods and results:, Four types of stroma were observed histologically; fibrous, desmoplastic, myxoid and myxoid with hyalinization. Osteoblast and osteoclast were counted using haematoxylin and eosin sections and immunohistochemistry with CD68. After histomorphometric analysis, only fibrous and myxoid types of stroma were distinctly identified. Secreted frizzled-related peptide (sFRP)-2, transforming growth factor-beta 1 and receptor activator of nuclear factor-,B ligand (RANKL) revealed strong expression in myxoid type compared with the normal stroma. Bone morphogenetic protein (BMP)-2 was negative in myxoid type, but positive in normal stroma. Fibrous-type stroma showed weak expression of all antigens except RANKL compared with myxoid type. Conclusions:, The results suggest that stroma does not act only in bone resorption, but also in the suppression of new bone formation. sFRP-2 is the main factor for impaired bone formation. The expression of markers related to osteoclastogenesis and suppression of osteoblast formation is higher in myxoid-type than in fibrous-type stroma. Tumour cells create a favourable environment for impaired bone formation by secreting sFRP-2 as well as bone resorption by secreting RANKL and interleukin-6. [source] Changing mental models: HR's most important taskHUMAN RESOURCE MANAGEMENT, Issue 2 2005Jeffrey Pfeffer In the "managerial knowledge" marketplace, there is little evidence of much diffusion of ideas, innovative business models, or management practices. In organizations not implementing what they know they should be doing based on experience and insight, and in companies not acting on the basis of the best available evidence, one main factor explains the difficulties,the mental models or mind-sets of senior leaders. How they are formed, what they are about, and a multitude of examples that show how those mind-sets can be improved are presented here. © 2005 Wiley Periodicals, Inc. [source] Isotope distribution of dissolved carbonate species in southeastern coastal aquifers of Sicily (Italy)HYDROLOGICAL PROCESSES, Issue 20 2007M. A. Schiavo Abstract Concentrations of major ions and the ,13C composition of dissolved inorganic carbon in groundwater and submarine groundwater discharges in the area between Siracusa and Ragusa provinces, southeastern Sicily, representing coastal carbonate aquifers, are presented and discussed. Most of groundwater analysed belongs to calcium bicarbonate type, in agreement with the geological nature of carbonate host rocks. Carbonate groundwater acquires, besides the dissolution of carbonate minerals, dissolved carbon (and the relative isotopic composition) from the atmosphere and from soil biological activity. In fact, ,13C values and total dissolved inorganic carbon contents show that both these sources contribute to carbon dissolved species in the waters studied. Finally, mixing with seawater in the second main factor of groundwater mineralization Copyright © 2007 John Wiley & Sons, Ltd. [source] Energy-Level Alignment at Organic/Metal and Organic/Organic InterfacesADVANCED MATERIALS, Issue 14-15 2009Slawomir Braun Abstract In this Review, we summarize recent work on modeling of organic/metal and organic/organic interfaces. Some of the models discussed have a semiempirical approach, that is, experimentally derived values are used in combination with theory, and others rely completely of calculations. The models are categorized according to the types of interfaces they apply to, and the strength of the interaction at the interface has been used as the main factor. We explain the basics of the models, their use, and give examples on how the models correlate with experimental results. We stress that given the complexity of organic/metal and organic/organic interface formation, it is crucial to know the exact way in which the interface was formed before choosing the model that is applicable, as none of the models presented covers the whole range of interface interaction strengths (weak physisorption to strong chemisorption). [source] An Empirical Analysis of Inflation in OECD CountriesINTERNATIONAL FINANCE, Issue 1 2004Jane Ihrig During the 1990s, many OECD countries had declining rates of inflation while their unemployment rates were also falling, something that on the surface seemed at odds with the Phillips curve relationship between inflation and unemployment. For the USA, these seemingly contradictory developments have been reconciled in terms of two factors: (1) an acceleration in productivity and (2) structural changes in labour markets that lowered the natural unemployment rate (NAIRU). Here we ask whether comparable forces were at work in 19 other industrial countries. We find that productivity advancements were the main structural factor reducing inflation only in the USA. In other industrial countries, persistent labour-market slack was the main factor exerting downward pressure on inflation. This persistence stemmed, in part, from structural reforms that lowered the NAIRU while the unemployment rate was declining. Ireland, New Zealand and Norway were three countries where labour-market reforms helped to push inflation down dramatically. [source] Rheological behavior of polymer melts in monodimensional flow through low-angle convergence and spiralling diesADVANCES IN POLYMER TECHNOLOGY, Issue 2 2001L. Mascia An experimental study was carried out to examine the rheological behavior of polymer melts in laminar flows through channels with small-angle convergences (2,3°) and spiralling walls (6°/mm along the flow direction), using an extrusion grade of low-density polyethylene. The results show that convergence is the main factor responsible for the observed deviations from steady state laminar shear flow, particularly with respect to additional pressure requirements to maintain a constant mass output. The swell ratio, calculated from the dimensions of the channel at the exit, was found to be considerably higher for flow-through converging channels. Only a small increase in swell ratio could be attributed, on the other hand, to the rotational elements of the die configuration. It is inferred that even for small angles of convergence the increased level of swelling is associated with elongational stress components, which were grouped together and denoted as the "additional stress." This was obtained from the difference between the calculated average shear stress at the wall, using the recorded pressure at the die entry, and the value of the average shear stress at the wall calculated from the shear viscosity data for the melt. © 2001 John Wiley & Sons, Inc. Adv Polym Techn 20: 99,107, 2001 [source] Teratogenicity of elevated egg incubation temperature and egg vitamin A status in Atlantic salmon, Salmo salar L.JOURNAL OF FISH DISEASES, Issue 4 2004R Ørnsrud Abstract The present study was undertaken to investigate the possibility that high egg vitamin A (VA) status in combination with elevated egg incubation temperatures may cause deformities in Atlantic salmon, Salmo salar L. Egg batches selected for their total VA concentration were exposed to low (normal, 8 °C) or elevated (14 °C) egg incubation temperatures. Temperature was the main factor causing bone deformities such as warped gill opercula, fin and jaw deformities, but not for the development of spinal deformities where all groups displayed a ,baseline' occurrence of mild deformity (decreased vertebral size in the cephalic region) and no systematic variation in the occurrence of serious spinal deformities (fused vertebrae). A possible effect of egg incubation temperature fluctuation was found for the groups reared at low temperatures. An indication of a negative effect of elevated egg VA status for the development of organ deformities such as missing septum transversum and situs inversus was found in addition to temperature effects, however, no firm conclusions could be drawn from the present data. The phenotypes for temperature-induced deformities resembled the phenotype of VA-induced deformities, but no clear conclusions on the causality of the deformities found in the present study could be drawn. Egg incubation temperatures, both absolute temperature and temperature variations, should therefore be strictly controlled. [source] CHARACTERISTIC DRYING CURVE and MATHEMATICAL MODELING of THIN-LAYER SOLAR DRYING of PRICKLY PEAR CLADODE (OPUNTIA FICUS INDICA)JOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2004S. LAHSASNI ABSTRACT Thin-layer solar drying experiments were conducted for the prickly pear cladode grown in Marrakech, Morocco. the experimental drying curves obtained show only a falling rate period. the results verified, with good reproducibility, that the drying air temperature is the main factor in controlling the drying rate. the expression of the drying rate equation was determined empirically from the characteristic drying curve. Eight different drying models were compared according to their correlation coefficient (r2) to estimate solar drying curves. the Page model could satisfactorily describe the solar drying curves of cladode with an r2 of 0.9995. the coefficient of this model could be explained by the effect of drying air temperature with an r2 of 1.0000. [source] Beer and Wine Consumers' Perceptions of the Nutritional Value of Alcoholic and Nonalcoholic BeveragesJOURNAL OF FOOD SCIENCE, Issue 1 2008C.A. Wright ABSTRACT:, In general beer has not been portrayed as part of a balanced diet. However, red wine has been promoted as a beneficial part of a nutritious diet. The evidence is that beer is at least the equal of wine from a nutritional perspective and in countering ailments such as coronary heart disease. This study used surveys to compare beer and wine consumers' perceptions of alcoholic and nonalcoholic beverages. The consumers ranked 7 beverages based upon perceived healthfulness both before and after they were exposed to nutritional information about the beverages. The ranked data were analyzed using analysis of variance. The variance due to the 3-way interaction of place of recruitment, beverage, and ranking was found to be significant at P < 0.05. There was no significant difference between genders. Overall, consumers of alcoholic beverages perceived red wine to be more healthful than the other 6 beverages, including beer and white wine. The perceived healthfulness of a beverage does not appear to be the main factor driving the choice of beverage. Nutritional information does impact consumers' perceptions of the healthfulness of beverages. Consumers who are predominately beer drinkers were more heavily influenced by nutritional information than consumers who were predominately wine drinkers. [source] Two-phase flow behavior in microtube reactors during biodiesel production from waste cooking oilAICHE JOURNAL, Issue 5 2010Guoqing Guan Abstract Flow patterns in the course of transesterification of waste cooking oil (WCO), sunflower oil (SFO) with water and/or oleic acid as a model of WCO, and pure SFO in the presence of a KOH catalyst in microtubes were investigated. FAME yield for the transesterification of WCO reached more than 89% in the microtube reactors with a residence time of 252 s at 333 K. The flow patterns when using WCO were changed from a liquid,liquid slug flow at the inlet region to a parallel flow at the middle region, and then to a homogeneous liquid flow at the outlet region as the reaction proceeded at 333 K. Fine droplets containing glycerol and methanol generally formed in oil slugs when using pure SFO, but were almost unobservable when using WCO. The soap produced from free fatty acids was considered to be the main factor affecting the flow patterns of WCO and SFO. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Dielectric properties of pharmaceutical materials relevant to microwave processing: Effects of field frequency, material density, and moisture contentJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 2 2010Paul W.S. Heng Abstract The rising popularity of microwaves for drying, material processing and quality sensing has fuelled the need for knowledge concerning dielectric properties of common pharmaceutical materials. This article represents one of the few reports on the density and moisture content dependence of the dielectric properties of primary pharmaceutical materials and their relevance to microwave-assisted processing. Dielectric constants and losses of 13 pharmaceutical materials were measured over a frequency range of 1,MHz,1,GHz at 23,±,1°C using a parallel-electrode measurement system. Effects of field frequency, material density and moisture content on dielectric properties were studied. Material dielectric properties varied considerably with frequency. At microwave frequencies, linear relationships were established between cube-root functions of the dielectric parameters ( and ) and density which enabled dielectric properties of materials at various densities to be estimated by regression. Moisture content was the main factor that contributed to the disparities in dielectric properties and heating capabilities of the materials in a laboratory microwave oven. The effectiveness of a single frequency density-independent dielectric function for moisture sensing applications was explored and found to be suitable within low ranges of moisture contents for a model material. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:941,957, 2010 [source] ROLE OF SURFACE WOUNDS AND BROWN ALGAL EPIPHYTES IN THE COLONIZATION OF ASCOPHYLLUM NODOSUM (PHAEOPHYCEAE) FRONDS BY VERTEBRATA LANOSA (RHODOPHYTA),JOURNAL OF PHYCOLOGY, Issue 3 2009Caroline M. Longtin Ascophyllum nodosum (L.) Le Jol. forms extensive beds in wave-sheltered, rocky intertidal habitats on the northwestern Atlantic coast. This fucoid seaweed is host to an obligate red algal epiphyte, Vertebrata lanosa (L.) T. A. Chr. [=Polysiphonia lanosa (L.) Tandy], and two facultative brown algal epiphytes, Elachista fucicola (Velley) Aresch. and Pylaiella littoralis (L.) Kjellm. Although V. lanosa can occur throughout most of the length of host fronds, it largely predominates in midfrond segments. The two brown algal epiphytes are restricted to distal segments. Through field experiments conducted in Nova Scotia, Canada, we tested the hypothesis that surface wounds are required for the colonization of distal segments of host fronds by V. lanosa. Distal tissues normally have a smooth surface because of their young age (A. nodosum fronds grow apically). By creating small wounds that mimicked grazing wounds distributed elsewhere on host fronds, we demonstrated that V. lanosa can colonize distal frond segments during the growth and reproductive season (summer and autumn). Approximately half of the artificial wounds were colonized by V. lanosa during this time. The experimental exclusion of both brown algal epiphytes from distal frond segments did not affect colonization by V. lanosa. Thus, we conclude that the absence of surface irregularities on distal segments of host fronds, specifically small wounds, is the main factor explaining the absence of V. lanosa there. We propose that further experimental work clarifying epiphyte distribution in host beds will enhance our ability to understand the functional role of epiphytes in intertidal ecosystems. [source] Preparation and characterization of phosphatidylcholine-coated zirconia,magnesia stationary phase for artificial membrane chromatographyJOURNAL OF SEPARATION SCIENCE, JSS, Issue 19 2010Weinong Zhang Abstract Immobilized artificial membrane chromatography stationary phase was prepared by coating soybean phosphatidylcholine (PC) on zirconia,magnesia micro-particles. The stability and chromatographic properties were investigated and compared with the PC-coated silica chromatography stationary phase prepared by the same method. PC-coated zirconia,magnesia chromatography stationary phase was more stable than the silica especially on resisting organic solvents. Hydrophobic action was the main factor for the retention of analyte on the new artificial membrane chromatography stationary phase, and electrostatic interaction had some contribution to retention. In addition, the special interaction between analyte and matrix affected retention greatly. Basic solutes were appropriate to be analyzed on PC-coated zirconia,magnesia stationary phase and acidic solutes were appropriate to be done on the silica one. Hence, the two different matrices artificial membrane stationary phases were perfectly complementary. [source] Factors influencing the adsorption of stabilizers onto carbon black: Flow microcalorimetry studiesJOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 2 2000J. M. Peñta The surface activity of various kinds of carbon black toward phenolic antioxidants and hindered amine light stabilizers (HALS) was examined by using flow microcalorimetry (FMC). Phenolic hydroxyl and ester groups were found to be the moieties responsible for the adsorption activity of primary phenolic antioxidants onto the carbon black surfaces. Furthermore, a difference in the degree of phenolic hydroxyl hindrance by alkyl groups was found to be the main factor affecting the adsorption activity of the phenol group. A difference in the degree of substitution of the piperidine amine, as well as the number and type of functionality per molecule, are important factors that were found to influence the adsorption activity of HALS. Data from adsorption studies using model compounds, some of which represented functional portions of the stabilizer molecules, reflected behavior sin ilar to that observed with the stabilizers. In addition, these latter results showed that FMC analysis can yield potentially useful information beyond that given by the usual parameters such as BET surface area, I2, DBP, and CTAB adsorption values. Differences in the behavior between types of carbon black were evident and showed that the specific surface area is not the most important factor in the adsorption/desorption activity, but also the chemical nature of the surface. From the activity observed for model compounds, it was deduced that the presence of secondary and tertiary amine in the backbone and branch structures also has an important role in the adsorption activity of polymeric HALS. In general, the observed quantities can be related to the values of adsorption/desorption energy and to the molar mass of the probe. [source] Prevalence of hepatitis C virus infection in thalassemia and haemodialysis patients in north Iran-RashtJOURNAL OF VIRAL HEPATITIS, Issue 5 2002M. M. Ansar summary.,Hepatitis C virus (HCV) seroprevalence and risk factors in north Iran were investigated in 105 thalassemia sufferers, 93 haemodialysis patients and 5976 blood donors by second generation ELISA. Our study showed that haemodialysis patients and thalassemia sufferers were at higher risk of having HCV infection; the prevalence being 55.9% and 63.8% respectively in comparison to the prevalence of blood donors (0.5%). A confirmatory immunoblotting was employed using HCV-positive cases (54 thalassemia sufferers and 19 blood donors). The result showed that 92.6% of samples of the first group and 10.5% of the latter were positive. Thus, it can be suggested that ELISA in low-risk cases may produce considerable false positives. In HCV-positive patients with thalassemia, the incidence of HCV among different age groups and genders was similar but a strong correlation in respect to the number of blood transfusion (P=0.008) was observed. In HCV-positive haemodialysis patients, it was found that there was no correlation with liver function tests (alanine aminotransferase and aspartate aminotransferase: ALT and AST), but a significant correlation was observed in respect to the duration of dialysis(P=0.000) and the number of units transfused (P=0.000). Consequently, it still seems blood transfusion is the main factor for increasing the incidence of HCV in thalassemia sufferers and haemodialysis patients. [source] Seasonal effects and fine-scale population dynamics of Aedes taeniorhynchus, a major disease vector in the Galapagos IslandsMOLECULAR ECOLOGY, Issue 20 2010ARNAUD BATAILLE Abstract Characterization of the fine-scale population dynamics of the mosquito Aedes taeniorhynchus is needed to improve our understanding of its role as a disease vector in the Galapagos Islands. We used microsatellite data to assess the genetic structure of coastal and highland mosquito populations and patterns of gene flow between the two habitats through time on Santa Cruz Island. In addition, we assessed possible associations of mosquito abundance and genetic diversity with environmental variables. The coastal and highland mosquito populations were highly differentiated from each other all year round, with some gene flow detected only during periods of increased precipitation. The results support the hypothesis that selection arising from ecological differences between habitats is driving adaptation and divergence in A. taeniorhynchus, and maintaining long-term genetic differentiation of the populations against gene flow. The highland and lowland populations may constitute an example of incipient speciation in progress. Highland populations were characterized by lower observed heterozygosity and allelic richness, suggesting a founder effect and/or lower breeding site availability in the highlands. A lack of reduction in genetic diversity over time in highland populations suggests that they survive dry periods as dormant eggs. Association between mosquito abundance and precipitation was strong in the highlands, whereas tide height was the main factor affecting mosquito abundance on the coast. Our findings suggests differences in the infection dynamics of mosquito-borne parasites in the highlands compared to the coast, and a higher risk of mosquito-driven disease spread across these habitats during periods of increased precipitation. [source] Analysis of water solubility data on the basis of HYBOT descriptors.MOLECULAR INFORMATICS, Issue 9-10 2003Part 1. Abstract This work describes the analysis of water-gas phase partitioning data Lw=Cw/Cg for 559 organic chemicals on the basis of physicochemical descriptors calculated by the HYBOT program package. Physicochemical descriptors combined with indicator variables as well as a new approach combining traditional QSAR and molecular similarity are used to take structural features into account. The H-bond acceptor ability of chemicals (i.e. interaction of acceptor atoms with hydrogen atoms of water) is the main factor that influences the partitioning of vapors into water. The simultaneous consideration of H-bond acceptor and donor factors leads to a description of the solubility of vapors with a correlation coefficient of about 0.92. The influence of steric interactions of solutes (characterized by means of molecular polarizability) with water molecules contributes slightly but significantly from the statistics point of view. The use of a set of indicator variables for hydrocarbons and for molecules containing amino, amido, CX3, ether and nitro groups as well as for molecules with ability to form intramolecular hydrogen bonds improves the correlation and helps to take structural features into account. Furthermore, the application of an approach based on the calculation of additional contributions to solubility by considering ,nearest neighbor chemicals' and their difference in physicochemical parameters gives in many cases good results and could be very useful in the analysis of vast data sets. [source] | ||||||||||||||||||||||||||||||||||||||||||||||