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Selected AbstractsLipid characterization of both wild and cultured eggs of cuttlefish (Sepia officinalis L.) throughout the embryonic developmentAQUACULTURE NUTRITION, Issue 1 2009A.V. SYKES Abstract The present work reports a characterization of mean wet weight and moisture, the lipid class and fatty acid (FA) composition from the total lipids (TL), of both culture and wild eggs of the cuttlefish, Sepia officinalis, throughout the embryonic development. Additionally, reproductive data, such as the number of spawnings, number and mean weight of eggs and duration of spawning period of cultured cuttlefish is provided. Both types of eggs were similar in mean wet weight, moisture content, TL content and lipid composition throughout embryonic development. Females from the cultured group spawned 13 times and laid 8654 eggs in 64 days, with a mean weight of 0.607 ± 0.179 g. A sex ratio of 1.57 (11, for 7,) promoted an individual fecundity of 787 eggs/, (the biggest until now on our culture facilities), which might be related to increased bottom areas. The TL increased with day/stage of embryonic development (P < 0.05) only in the cultured egg group. However, no differences were found on TL between culture and wild eggs at the same day/stage (P > 0.05). Eggs displayed predominant levels of phosphatidylcholine, phosphatidylethanolamine (PE), cholesterol and triacylglycerol at the end of embryonic development. Polar and neutral lipids of both eggs groups remained consistently proportional (,50% for each lipid fraction) and a significant increase (P < 0.05) was observed in phosphatidylserine, PE and free FA throughout the embryonic development. In either egg type and day, 16:0, 18:0, 20:5n-3 and 22:6n-3 accounted for approximately 70 g Kg,1 of all FA and saturated and n-3 totals seemed to have the same proportion in the cuttlefish eggs. The present results suggest that lipids are not used as energetic substrate but as structural components in cuttlefish egg. [source] Segment-specific expression of connexin31 in the embryonic hindbrain is regulated by Krox20DEVELOPMENTAL DYNAMICS, Issue 4 2002Stefan Jungbluth Abstract Communication and interaction between cells has been shown to be important during the embryonic development of the vertebrate hindbrain, which becomes transiently subdivided into segments called rhombomeres (r). One gene family allowing intercellular communication and possibly being involved in the control of hindbrain development is the connexin family encoding gap junction channels. Here, we have characterized in detail the previously observed (Dahl et al., 1997) expression of one particular connexin gene, connexin31 (Cx31), in the mouse embryonic hindbrain and compared it with that of Cx43 and Cx36. We found transient Cx31 expression from approximately embryonic day (E) E8,E11 in two small lateral/dorsal subgroups of cells in the hindbrain. We could show that these spots of expression corresponded to r3 and r5 and that Cx31 expression in r3 and r5 was controlled by the transcription factor Krox20. In contrast, expression of Cx43 and Cx36 started later (from E9.5 and E10.5, respectively) and was confined to longitudinal stripes of expression. In addition, from E10.5,E11.5, Cx31 was expressed by a column of cells in ventral r4, most likely representing contralateral vestibulo-acoustic efferent neurons, immediately anterior to a ventral column expressing Cx36 at the same stage. From E11.5 onward, another site of Cx31 expression was detected in the boundary cap cells in the entry/exit points of all mixed sensory/motor and in the entry points of pure sensory nerves. This expression was not present in the boundary cap cells of the exit points of pure motor nerves. So far, our analysis of the hindbrain area of Cx31 -deficient embryos in terms of projections of sensory or motor neurons or in the generation or migration of neurons has not yet revealed any obvious defects. © 2002 Wiley-Liss, Inc. [source] Light and scanning microscopic studies of integument differentiation in the grass snake Natrix natrix L. (Lepidosauria, Serpentes) during embryogenesisACTA ZOOLOGICA, Issue 1 2009Elwira Swad Abstract We analysed the differentiation of body cover in the grass snake (Natrix natrix L.) over the full length of the embryo's body at each developmental stage. Based on investigations using both light and scanning electron microscopes, we divided the embryonic development of the grass snake integument into four phases. The shape of the epidermal cells changes first on the caudal and ventral parts of the embryo, then gradually towards the rostral and dorsal areas. In stage V on the ventral side of the embryo the gastrosteges are formed from single primordia, but on the dorsal side the epidermis forms the scale primordia in stage VII. This indicates that scalation begins on the ventral body surface, and spreads dorsally. The appearance of melanocytes between the cells of the stratum germinativum in stage VII coincides with changes in embryo colouration. The first dermal melanocytes were detected in stage XI so in this stage the definitive skin pattern is formed. In the same stage the epidermis forms the first embryonic shedding complex and the periderm layer begins to detach in small, individual flakes. This process coincides with rapid growth of the embryos. [source] Canal shapes produced sequentially during instrumentation with Quantec SC rotary nickel,titanium instruments: a study in simulated canalsINTERNATIONAL ENDODONTIC JOURNAL, Issue 2 2001I. T. Griffiths Abstract Aim The aim of this study was to determine the shaping ability of Quantec SC nickel,titanium rotary instruments in simulated root canals. Methodology Forty simulated canals consisting of four different shapes in terms of angle and position of curvature were prepared with Quantec SC instruments. Sequential still images were taken of the canals using a video camera attached to a computer with image analysis software. Images were taken preoperatively, and then after instrument 7 (Size 25, 0.05 taper), instrument 8 (size 25, 0.06 taper), and instrument 10 (size 45, 0.02 taper) were taken to length. Each sequential postoperative image was superimposed individually over the preoperative image in order to highlight the amount and position of material removed during preparation. Results Overall, the mean preparation time to size 10 was 3.6 min with 12 mm canals taking on average less time than 8 mm canals. There was a highly significant difference between the canal types (P < 0.0001). No instruments fractured within the canal or deformed, although one instrument separated from the latch grip. All canals remained patent. Following preparation to size 10, 19 canals (48%) retained their length, eight (20%) lost length, and 13 (32%) gained length; the magnitude of the change in length was always 0.5 mm or below. Following preparation to size 7 instruments all canals showed aberrant shapes. Excess removal of material along the outer aspect of the curve between the beginning of the curve and the end-point (outer widening) was found in 26 canals (65%) after instrument 7. At the same stage of preparation six canals (15%) had zips, three (8%) had ledges and five (13%) had perforations. Following preparation to size 10, 27 (68%) canals were perforated. Conclusions Under the conditions of the study, Quantec SC instruments consistently produced aberrations when canals were enlarged to size 7 (size 25, 0.05 taper) or above. Care should be exercised when using these instruments in real teeth. [source] The effect of the time and mode of application of gibberellic acid and inhibitors of gibberellin biosynthesis on the dormancy of potato tubers grown from true potato seedJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 10 2007Alexios A Alexopoulos Abstract Gibberellic acid (GA3) and inhibitors of gibberellin biosynthesis (daminozide and chlormequat chloride) were applied to the foliage of potato plants grown from true seed (TPS) either once at two stages of plant development, 40 and 60 days after transplantation (DAT), or repeatedly at 10 day intervals starting from the same growth stages. When GA3 was applied towards the end of the vegetative cycle (either singly 60 DAT or repeatedly from the same date), it induced rapid breakage of tuber dormancy, a reduction in specific weight, a higher rate of respiration and increased weight loss during storage. Single applications of GA3 early in the vegetative cycle (40 DAT) had no effect on the weight loss and specific weight of tubers during storage, whereas repeated foliar applications of GA3 starting from the same stage resulted in the formation of tubers with a low specific weight and a high rate of weight loss during storage. However, the tubers from these treatments did not break dormancy uniformly, and, although in the early stages of storage they exhibited a high rate of respiration, this declined to the level of the control (no growth regulator applied). Although daminozide and chlormequat chloride did not affect the duration of tuber dormancy and had little or no effect on any of the other metabolic indicators studied, gibberellin is nevertheless implicated in dormancy breakage, and its application late in the growth cycle may be of practical value in cases where tubers are required for planting soon after harvest. Overall, tubers from TPS respond to plant growth regulator treatment in a similar way to those from plants grown from seed tubers. Copyright © 2007 Society of Chemical Industry [source] Subacute reconstruction of lower leg and foot defects due to high velocity-high energy injuries caused by gunshots, missiles, and land minesMICROSURGERY, Issue 1 2005Bahattin Çeliköz M.D. The present study reviews 215 male patients suffering high velocity-high energy injuries of the lower leg or foot caused by war weapons such as missiles, gunshots, and land mines. They were treated in the Department of Plastic and Reconstructive Surgery at Gülhane Military Medical Academy (Ankara, Turkey) between November 1993,January 2001. Severe soft-tissue defects requiring flap coverage and associated open bone fractures that were treated 7,21 days (mean, 9.6 days) after the injury were included in the study. Twenty-three of 226 extremities (10.2%) underwent primary below-knee amputation. The number of debridements prior to definitive treatment was between 1,3 (mean, 1.9). Gustilo type III open tibia fractures accompanied 104 of 126 soft-tissue defects of the lower leg. Sixty-four bone defects accompanied 83 soft-tissue defects of the feet. Eighteen local pedicled muscle flaps and 208 free muscle flaps (latissimus dorsi, rectus abdominis, and gracilis) were used in soft-tissue coverage of 209 defects. Overall, the free muscle flap success rate was 91.3%. Bone defects were restored with 106 bone grafts, 25 free fibula flaps, and 14 distraction osteogenesis procedures. Osseous and soft-tissue defects were reconstructed simultaneously at the first definitive treatment in 94% of cases. The mean follow-up after definitive treatment was 25 (range, 9,47) months. The average full weight-bearing times for lower leg and feet injuries were 8.4 months and 4 months, respectively. Early, aggressive, and serial debridement of osseous and soft tissue, early restoration of bone and soft-tissue defects at the same stage, intensive rehabilitation, and patient education were the key points in the management of high velocity-high energy injuries of the lower leg and foot. © 2005 Wiley-Liss, Inc. Microsurgery 25:3,15, 2005. [source] Covariance-oriented qualitative and quantitative calibration analysis for multistage batch processesTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2009Chunhui Zhao Abstract An improved stage-specific multivariate calibration scheme is developed for multistage batch processes based on the covariance analysis unit. First, the process duration is automatically and properly divided into different stages, which reveals the changes of quality-related process correlation characteristics. The concept of stage-representative average process behaviour is then introduced, which is comprehensibly realized by averaging all covariance patterns within the same stage based on different weights. In this way, it stacks the cumulative effects of process variations on quality within each stage and meanwhile considers their time-varying characteristics. Subsequently, covariance-oriented OSC and variable selection are effectively combined, which can simplify the calibration model structure and enhance the causal relationship between predictors and quality by excluding the redundant latent factors and input variables. Finally, stage-representative PLS regression models are developed focusing on the critical-to-quality stages for online quality prediction. It shows that a complete multistage calibration solution is readily achieved from an "overall" stage perspective by smartly making use of covariance. The illustration study to injection molding shows the effectiveness of the proposed method for improving process comprehension and quality prediction. On a mis au point un schéma amélioré d'étalonnage multivarié pour des procédés discontinus multi-étapes, spécifique à chaque étape, basé sur l'analyse des covariances sans tenir compte de chaque variable de procédé. En premier lieu, la durée de procédé est automatiquement et correctement divisée en quatre étapes différentes, révélant le changement des caractéristiques de corrélation de procédé lié à la qualité. Le concept de comportement de procédé moyen représentatif d'une étape est alors introduit, ce qui se réalise de façon complète en moyennant tous les profils de covariance d'une étape donnée avec différentes pondérations. De cette façon, on tient compte dans la qualité des effets cumulatifs des variations de procédé spécifiques à chaque étape et considère de ce fait leurs caractéristiques évolutives. Par conséquent, l'OSC orienté vers la covariance et la technique de sélection des variables sont combinés efficacement afin de simplifier la structure du modèle d'étalonnage et améliorer la relation causale en excluant les facteurs latents redondants ou les variables d'entrée. Enfin, des modèles de régression de type PLS représentatifs des étapes sont mis au point, mettant l'accent sur les étapes critiques en terme de qualité pour la prédiction de la qualité en ligne. Cela montre qu'une solution complète d'étalonnage multi-étapes peut se réaliser parfaitement en utilisant bien la covariance. L'illustration dans le cas du moulage par injection montre l'efficacité de la méthode proposée pour la compréhension du procédé et l'amélioration des prédictions. [source] WTO Constraints on Domestic Support in Agriculture: Past and FutureCANADIAN JOURNAL OF AGRICULTURAL ECONOMICS, Issue 1 2009Lars Brink The domestic support provisions in the WTO Agreement on Agriculture originate in the 1958 Haberler Report. Economic analysis often overlooks the agreement's legally important distinctions. Few domestic support issues lead to dispute settlement proceedings. The Doha negotiations would result in more constraints on domestic support than the sole commitment on Total Aggregate Measurement of Support (AMS) in the present agreement: ceilings on overall trade-distorting support and blue box payments, and also product-specific caps. Some 18 members would reduce their Total AMS commitments, and 25 would reduce the de minimis percentages. Most members would not reduce their constraints at all or only little. If today's developing countries continue to grow as they did in recent decades, their capacity to support agriculture increases significantly. If they then choose to support agriculture as today's developed countries did at the same stage of economic development, the future WTO constraints on trade-distorting domestic support would allow them to provide considerably more such support than developed countries. Les règles sur le soutien interne de l'Accord sur l'agriculture de l'OMC tirent son origine du rapport ,Haberler, de 1958. L'analyse économique oublie souvent les distinctions d'importance juridique de l'accord. Peu de questions en soutien interne entraînent des procédures de règlement des différends. Les négociations de Doha se solderaient par plus de contraintes sur le soutien que le seul engagement de l'accord actuel, celui sur la mesure globale de soutien (MGS) totale. Ces contraintes comprennent des plafonds sur le soutien interne global ayant des effets de distorsion des échanges et sur les paiements dans la boîte bleue, ainsi que des plafonds par produit. Environ 18 membres réduiraient leurs engagements sur la MGS totale, et 25 membres réduiraient les pourcentages de minimis. La plupart des membres ne réduiraient pas leurs engagements ou les réduiraient seulement un peu. Si la croissance économique des pays, qui aujourd'hui sont en voie de développement, continue au même taux que dans les décennies récentes, leur capacité de soutenir leur agriculture augmente. S'ils choisissaient dans l'avenir de soutenir leur agriculture, comme l'ont fait les pays qui sont aujourd'hui les pays développés lorsqu'ils se trouvaient au même stage de développement, les contraintes futures de l'OMC sur le soutien interne faussant les échanges permettraient aux pays en voie de développement d'accorder de tel soutien dans des montants considérablement plus importants que ceux des pays développés. [source] Technology Forecasting: From Emotional to EmpiricalCREATIVITY AND INNOVATION MANAGEMENT, Issue 2 2001Michael S. Slocum Technology Forecasting has evolved from being a methodology based on emotional responses to one predicated on data collection. The Theory of Inventive Problem Solving (TRIZ) is a theory based on empirical data that relates technological evolution to the same stages of biological macro-evolution. This paper will explore the major emotional forecasting methods as well as discuss part of TRIZ Technology Forecasting called Maturity Mapping. The reader will briefly be introduced to eight evolutionary trends based on TRIZ. [source] | |||||||||||||||||||