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Wave forecasting may represent a useful tool for safety assessment of maritime works and activities. To date, wave forecasting uncertainty is usually corrected by using either the mean calibration factor or the time series method. However, within the frame of maritime work management it is necessary to forecast – with an acceptable probability of error – whether or not the significant wave height at a given location will exceed a prefixed threshold within a specified temporal window, so as to assess the safety of the specified temporal window with respect to the activity to be carried out. The present paper aims to illustrate a general criterion useful to correct wave forecast, i.e. to provide an engineering tool able to assess the safety of the temporal window needed to complete a specified maritime work. The paper provides a detailed description of the method, together with the application to a real case. [ABSTRACT FROM AUTHOR]

Beacon-immunoreactive (B-ir) fibres and neurons in the hypothalamus of the domestic chick ( Gallus domesticus) were studied using an immunohistochemical technique in order to verify the presence and elucidate the pattern of distribution of this novel peptide in an avian brain. B-ir neurons were seen in the n. supraopticus, pars ventralis and pars externus; n. magnocellularis preopticus, pars dorsalis, medialis and ventralis; n. preopticus periventricularis; n. suprachiasmaticus, pars medialis; n. ventrolateralis thalami. Only few B-ir cells were scattered in the most anterior part of the lateral hypothalamic area. B-ir fibres, appearing as thin punctuate structures, were seen mainly along the walls of the third ventricle and in the ventromedial hypothalamus. Labelled fibres and terminals were located in the external and internal zones of the anterior and posterior median eminence. In particular, fibre terminals were seen close to the capillary loops of the hypothalamo-hypophysial portal system. The anatomical data of the present study regarding the distribution of B-ir in the chick hypothalamus suggest that beacon may play a key role in the regulation of the neuroendocrine system by acting as a neuromodulator and/or neurotransmitter. [ABSTRACT FROM AUTHOR]

The present study investigates the occurrence of Trk-like neurotrophin receptor proteins in the lizard and frog kidney. In lizard rare TrkB-like immunoreactive cells in intermediate and distal tubules were found. TrkC-like immunoreactive cells were numerous in collecting tubules and became less numerous in collecting ducts. No TrkC-like immunoreactivity was detected in the ureteric duct. In the frog, we observed numerous TrkC-like immunoreactive cells in collecting tubules and ducts while they were scattered among negative epithelial cells in the wolffian duct. TrkB- and TrkA-like immunoreactivity was never found. Western blot analysis demonstrated that the frog and lizard kidney contains TrkC-like protein; TrkB-like protein was present only in the lizard kidney. These results demonstrate for the first time the occurrence of Trk-like proteins in the kidney of amphibians and reptiles, and aid in the assessment of the role of Trk receptor-like proteins in the kidney physiology of vertebrates. [ABSTRACT FROM AUTHOR]

Berms deployed at the toe of conventional breakwaters may be needed to reduce bottom settlements and to limit scour in front of the structure due to coastal currents. In the mean time, they may be effective in increasing the stability of the armor layer and also in minimizing the wave overtopping discharge compared to straight sloped conventional breakwaters without a berm. This research aims to provide a new design criterion for the armor layer of conventional breakwaters with submerged berms marked by small thickness compared to water depth. Indeed, past researches focused on the influence of relatively high berms on the stability of the armor layer. The design of the berm itself is not tackled herein. The effects of submerged berms on the incident waves transformation have been evaluated by means of a numerical model, validated by using experimental data. Then, a parametric correction factor of the incident significant wave height at the toe of the structure is provided and included in well established design criteria. The experimental comparison confirms the reliability of the proposed method by highlighting the importance to use design criteria within their validity ranges, in order to avoid an unsafe dimensioning of the armor elements. [ABSTRACT FROM AUTHOR]

Semi-enclosed basins are often prone to storm surge events. Indeed, their meteorological exposition, the presence of large continental shelf and their shape can lead to strong sea level set-up. A real time system aimed at forecasting storm surge may be of great help to protect human activities (i.e. to forecast flooding due to storm surge events), to manage ports and to safeguard coasts safety. This paper aims at illustrating a simple method able to forecast storm surge events in semi-enclosed basins in real time. The method is based on a mixed approach in which the results obtained by means of a simplified physics based model with low computational costs are corrected by means of statistical techniques. The proposed method is applied to a point of interest located in the Northern part of the Adriatic Sea. The comparison of forecasted levels against observed values shows the satisfactory reliability of the forecasts. [ABSTRACT FROM AUTHOR]

This study reports the immunohistochemical localization and distribution of orexin A and B-like and their receptors-like peptides in the gastroenteric tract of chicken. The immunoreactivity is distributed in endocrine cells, nerve fibers and neurons, both in the stomach and intestine, and shows a discrete conformity with the data till now reported for Mammals. Our study suggests a possible participation of orexin-like peptides in the modulation of chicken gastroenteric activities and the preservation of their main distribution compared to Mammals. Western blot analysis has confirmed the presence of prepro-orexin and both receptors in the examined tissues. This survey represents the first evidence of the presence of orexin-like peptides in the gastroenteric tract of non mammalian species, and the results could help to better understand the alimentary control and body weight in domestic birds, which are of relevance to determine the productive factors in breeding animals. This study might also serve as a baseline for future experimental studies on the regulation of the gastroenteric functions in non mammalian Vertebrates. [ABSTRACT FROM AUTHOR]

RET receptor is a transmembrane protein which, together with the glial-cell-line derived neurotrophic factor family receptors alpha, forms a receptor complex upon activation by the glial-cell-line-derived neurotrophic ligands (GFLs). RET signaling is crucial for: (a) development of the enteric nervous system and kidney; (b) development of sympathetic, parasympathetic, motor, and sensory neurons; (c) postnatal maintenance of dopaminergic neurons; (d) spermatogenesis. In humans, RET mutations cause the Hirschsprung's disease, characterized by megacolon aganglionosis, and different types of cancer, the multiple endocrine neoplasia type 2A and type 2B and familial medullary thyroid. In the earliest aged cat embryos studied (stage 9 according to Knopse), RET immunoreactivity (IR) was observed in few cells detected in bilateral rows extending latero-ventrally to the neural tube and dorsolaterally to the foregut. In the successive aged group (stage 11), RET IR was observed in few single or grouped epithelial cells of the anterior gut and in small clustered cells scattered in the mesenchyme around the anterior gut. From stage 14-22 (the last stage 22 includes foetuses around the birth), RET IR was seen in neurons and fibers of the enteric nervous system. The appearance and intensification of RET-IR in the gut occurred with cranio/caudal and external/internal directions during the development. These results, thus, suggest the involvement of GFLs in the neuroblast migration, proliferation and differentiation. For a short period of development, these molecules might also act on some cells of the epithelium. [ABSTRACT FROM AUTHOR]

Abstract This paper aims at investigating the intensity of the load applied by non-breaking waves on the recurved parapet wall of vertical breakwaters. For this purpose, 2-D experiments were carried out on a simple vertical breakwater physical model with four different geometries of the parapet (with an "exit angle" of recurve of 0°, 45°, 60° and 90°), under both regular and irregular waves. The tests showed the presence of loads of a quasi-static nature and loads with a typical church roof impulsive behaviour, depending on the (non breaking) wave characteristics and on the shape of the parapet. This impulsive force resulted significantly larger than the quasi-static load of the pure vertical wall case. The maximum measured total force under regular waves was compared with the one obtained by a numerical model based on IHFOAM. For irregular waves with H s equal to 80% of the freeboard, the maximum measured horizontal load on a 90° recurved wall is equivalent to the force applied by a constant pressure of order 5 ρ gH s. It was found, by analysing waves near the leading edge of a wave-group, that history effects are important, i.e., in certain circumstances, a high wave preceded by lower waves generated a larger force than if it had been preceded by waves of the same height. For regular tests, the largest impulsive forces occurred basically at the beginning of the tests, during the initial transient ramp-up period. The irregular wave overtopping was also measured, showing good agreement with the existing predictive formulae and confirming the significant reduction of mean discharge with increasing exit angle and overhanging extension of the parapet. Highlights • Four geometries of the parapet were tested, with exit angle 0°, 45°, 60°, and 90°. • Regular (RW) and irregular waves (IW) were generated. • Under IW, impulsive loads (IL) were 5 times larger for 90° parapet than for 0°. • Under RW, IL were smaller than under IW, except for the initial transient phase. • The measured loads were predicted with satisfaction by numerical simulations. • The overtopping was in good agreement with the existing predictive formulae. [ABSTRACT FROM AUTHOR]

This paper describes 2-D numerical simulations of velocity and pressure fields generated by non-breaking waves on a vertical breakwater with a recurved parapet wall. The influence of the geometrical characteristics of the parapet is investigated. An impulsive pressure force is identified and discussed with respect to the pure vertical wall case. This force is generated by the seaward flow confinement induced by the surging wave crest. We refer to this impulsive impact as “confined-crest impact”. A large part of the vertical wall is affected by an impulsive increase in pressure caused by pulsating wave, compared to the case where the parapet is completely vertical. The maximum values of the impulsive pressures are localized under the recurved parapet. The total force increase on the entire structure may be significant when compared to the pure vertical wall case. [ABSTRACT FROM AUTHOR]

This paper presents a new experimental campaign aimed at reproducing tsunamis generated by landslides at the flank of conical islands. In order to describe in high details the wave field around the island a special acquisition system, which consists of both fixed and movable wave gauges, has been employed. Indeed, each experiment has been repeated several times by changing the configuration of the movable gauges, then obtaining a single virtual experiment with high spatial resolution measurements. Fixed run-up gauges measure the waves at fixed locations to statistically quantify the repeatability of the experiments. Selected experimental results are illustrated within the paper that is mainly aimed at defining a benchmark dataset, available on request, for the development/calibration/validation of analytical and numerical models of tsunamis generated by landslides. [ABSTRACT FROM AUTHOR]

The brain-derived neurotrophic factor ( BDNF) gene is expressed in differentiating and post-mitotic neurons of the zebrafish embryo, where it has been implicated in Huntington's disease. Little is known, however, about the full complement of neuronal cell types that express BDNF in this important vertebrate model. Here, we further explored the transcriptional profiles during the first week of development using real-time quantitative polymerase chain reaction (RT- qPCR) and whole-mount in situ hybridization (WISH). RT- qPCR results revealed a high level of maternal contribution followed by a steady increase of zygotic transcription, consistent with the notion of a prominent role of BDNF in neuronal maturation and maintenance. Based on WISH, we demonstrate for the first time that BDNF expression in the developing brain of zebrafish is structure specific. Anatomical criteria and co-staining with genetic markers ( shh, pax2a, emx1, krox20, lhx2b and lhx9) visualized major topological domains of BDNF-positive cells in the pallium, hypothalamus, posterior tuberculum and optic tectum. Moreover, the relative timing of BDNF transcription in the eye and tectum may illustrate a mechanism for coordinated development of the retinotectal system. Taken together, our results are compatible with a local delivery and early role of BDNF in the developing brain of zebrafish, adding basic knowledge to the study of neurotrophin functions in neural development and disease. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To understand whether patients with post-ischemic dilated cardiomyopathy and myocardial viability (MV) could benefit from cardiac resynchronization therapy (CRT) in terms of clinical, echocardiographic and neuro- hormonal parameters compared to patients without MV. METHODS: One hundred and four consecutive patients were enrolled in a prospective observational cohort study. Using dobutamine stress echocardiography, 2 groups were identified: group A of 51 patients with MV and group B of 53 patients without MV. All patients were implanted with biventricular pacing devices combined with an internal cardioverter-defibrillator. Clinical, echocardiographic and neuro-hormonal parameters were evaluated at baseline and at six month follow-up. Analysis of variance for repeated measures on each variable suggestive of remodeling was performed. We considered responder every patient with: decrease of > 15% in left ventricular volumes and/or improvement in left ventricular ejection fraction of > 5% in addition to NYHA class improvement. RESULTS: All the variables improved in both groups (time effect). Comparing the two groups (group effect), the following variables were significantly better in group A: N-terminal pro-B-type natriuretic peptide (p=0.02), NYHA class (p=0.003), reverse remodeling (RR) (p=0.007), dP/dt (p=0.005), left ventricular ejection fraction (p=0.009), 3rd sound (p=0.01), and left ventricular end-systolic volume after the first week (p=0.035). RR occurred at the first week after CRT only in Group A and was maintained for all the time of this study. The maximum difference of the decrease of left ventricular volumes between the two groups occurred after the first week (p<0.001). CONCLUSION: Patients with MV responded better than patients without MV with a significant improvement after the first week from CRT. [ABSTRACT FROM AUTHOR]

Abstract: This paper illustrates the results of an experimental investigation (model-to-prototype length ratio equal to 12) carried out to reproduce the cross-shore evolution of nourished sandy beaches. New two-dimensional experiments were performed to study the short-term response of the cross-shore profile for both “soft” (unprotected) and “mixed” (protected by submerged breakwaters) beach fill projects. Due to the simplified reproduction of prototype conditions in a two-dimensional geometry, only cross-shore sediment transport is considered. The results are related to the immediate post-nourishment evolution and far from beach fill boundaries where long-shore gradients of long-shore sediment transport are likely to be negligible. Three different pseudo-random wave trains were generated in order to simulate both accretive and erosive conditions. A fourth wave train, characterised by time-varying incident wave spectrum was generated for the investigation of the beach response to simplified storm time evolution. Dimensionless experimental results are given in terms of wave parameters, key features of cross-shore profile evolution and sediment transport rates. Furthermore, being highly resolved in both time and space, experimental data are suitable for mathematical model validation. It was observed that submerged breakwater switches erosive conditions to slightly accretive, at least within the tested experimental range. [Copyright &y& Elsevier]