Involvement of the V2 Vasopressin Receptor in Adaptation to Limited Water Supply

Mammals adapted to a great variety of habitats with different accessibility to water. In addition to changes in kidney morphology, e.g. the length of the loops of Henle, several hormone systems are involved in adaptation to limited water supply, among them the renal-neurohypophysial vasopressin/vasopressin receptor system. Comparison of over 80 mammalian V2 vasopressin receptor (V2R) orthologs revealed high structural and functional conservation of this key component involved in renal water reabsorption. Although many mammalian species have unlimited access to water there is no evidence for complete loss of V2R function indicating an essential role of V2R activity for survival even of those species. In contrast, several marsupial V2R orthologs show a significant increase in basal receptor activity. An increased vasopressin-independent V2R activity can be interpreted as a shift in the set point of the renal-neurohypophysial hormone circuit to realize sufficient water reabsorption already at low hormone levels. As found in other desert mammals arid-adapted marsupials show high urine osmolalities. The gain of basal V2R function in several marsupials may contribute to the increased urine concentration abilities and, therefore, provide an advantage to maintain water and electrolyte homeostasis under limited water supply conditions

Deep water prestack multiple suppression on reflection data from ionian sea (offshore western greece)

Multiple attenuation comprises a very important phase of the seismic reflection processing because it removes undesirable effects occurred during the propagation of the seismic signal in the earth. The present work aims at presenting the effectiveness of modern multiple suppression methods applied on streamer seismic reflection data. The seismic dataset represents an area with moderately dipping seafloor. The specific dataset was chosen in order to present the elimination of the water-column reverberations and internal multiples in dipping layers. Strong seafloor and internal multiples, lateral reflections and coherent noise impose difficulties in discriminating primary reflections in the seismic image of the present work. The prestack demultiple scheme combines wave equation method and deconvolution in order to predict and attenuate water-column reverberations and internal multiple reflections respectively. In particular, the region of moderately dipping seafloor chosen for the application of the proposed scheme images the Frontal Bulge in the outer Hellenic arc. The prestack demultiple method improved the quality of the stacked and migrated sections, by attenuating the majority of multiple reflections and extracting information about the structural units of the study area

Deep water prestack multiple suppression on reflection data from ionian sea (offshore western greece)

Multiple attenuation comprises a very important phase of the seismic reflection processing because it removes undesirable effects occurred during the propagation of the seismic signal in the earth. The present work aims at presenting the effectiveness of modern multiple suppression methods applied on streamer seismic reflection data. The seismic dataset represents an area with moderately dipping seafloor. The specific dataset was chosen in order to present the elimination of the water-column reverberations and internal multiples in dipping layers. Strong seafloor and internal multiples, lateral reflections and coherent noise impose difficulties in discriminating primary reflections in the seismic image of the present work. The prestack demultiple scheme combines wave equation method and deconvolution in order to predict and attenuate water-column reverberations and internal multiple reflections respectively. In particular, the region of moderately dipping seafloor chosen for the application of the proposed scheme images the Frontal Bulge in the outer Hellenic arc. The prestack demultiple method improved the quality of the stacked and migrated sections, by attenuating the majority of multiple reflections and extracting information about the structural units of the study area

THE RELATIONSHIP BETWEEN EMOTIONS AND CONFIDENCE AMONG GREEK ATHLETES FROM DIFFERENT COMPETITIVE SPORTS

Emotional relationships are crucial for an accurate prediction and control of the impact of emotions on athletic performance. The Individual Zones of Optimal Functioning (IZOF) model attempts to describe and explain emotions related to individually successful and poor performances (Hanin, 1997, 2000). The participants were 617 Greek athletes (424 males and 190 females) from five different sports. Their ages ranged from 18 to 30 years (M=24.30, SD=3.70). All athletes completed the questionnaire on emotions (IZOF, Hanin, 2000), which was translated into Greek (Hanin, Papaioannou & Lukkarila, 2001). The aim of the study was the examination of a possible relationship between emotions and confidence and among different competitive sports in Greece. The results supported the good psychometric properties of the assessment tool. Additionally, the results indicated statistically significant differences among sports in almost all the questionnaire variables: (a) in optimal-pleasant emotions swimmers had higher scores than Graeco-Roman and freestyle wrestlers, (b) in optimal-unpleasant emotions swimmers had higher scores than taekwondoists and water polo players, and (c) in dysfunctional-unpleasant emotions swimmers had lower scores than taekwondoists and water polo players. On the other hand, in dysfunctional-pleasant emotions and in confidence no statistically significant differences among the sports were found. According to previous research, it is also important to indicate that emotional content and intensity are different in training practice and competitions and that they vary across the pre-, mid-, and post-event performance situations (Hanin & Stambulova, 2002). Possible future research might replicate and extend the study's findings, explore an athlete's anxiety, goal-orientations, motivation and performance, and develop effective intervention strategies

Deep water prestack multiple suppression on reflection data from ionian sea (offshore western greece)

Summarization: Multiple attenuation comprises a very important phase of the seismic reflection processing because it removes undesirable effects occurred during the propagation of the seismic signal in the earth. The present work aims at presenting the effectiveness of modern multiple suppression methods applied on streamer seismic reflection data. The seismic dataset represents an area with moderately dipping seafloor. The specific dataset was chosen in order to present the elimination of the water-column reverberations and internal multiples in dipping layers. Strong seafloor and internal multiples, lateral reflections and coherent noise impose difficulties in discriminating primary reflections in the seismic image of the present work. The prestack demultiple scheme combines wave equation method and deconvolution in order to predict and attenuate water-column reverberations and internal multiple reflections respectively. In particular, the region of moderately dipping seafloor chosen for the application of the proposed scheme images the Frontal Bulge in the outer Hellenic arc. The prestack demultiple method improved the quality of the stacked and migrated sections, by attenuating the majority of multiple reflections and extracting information about the structural units of the study area.Presented on: Annals of Geophysic