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Volcanic and tectonic features significantly differ depending on the eruption styles and on the tectonic processes from which they were originated.We present here a study focused on the identification and characterization of Earth volcanic and tectonic structures by analyzing a combination of airborne and satellite optical images and Synthetic Aperture Radar (SAR) data. Our work is aimed at developing a robust approach to compare Earth and other terrestrial planet’s surface features, and to constrain their nature and occurrence in relation to volcano-tectonic activity.We focus on the Mt. Etna and the Aeolian Islands, which host several active volcanoes (e.g., Stromboli and Vulcano) and represent one of the most tectonically and magmatically active zones in the Mediterranean Sea area. Indeed, Etna, Vulcano and Stromboli, despite their geographical proximity, provide examples of very different volcanic activities and thus of diverse complex morphologies.The first stage of this study includes the processing of Pleiades tri-stereo acquisitions and high resolution DEMs of the regions of interest. This dataset will be analyzed through a novel automatic feature extraction algorithm that identifies the most common structures originating from natural processes, i.e., volcano-tectonic activities, and strong erosions.Pyroclastic cones, lava flows and fissures are some of the signs that we can detect and compare with accurate volcano-tectonic maps and geological maps. This further step will allow resolving their nature and origins, distinguishing features based on geometric criteria and according to the volcanic and tectonic processes that generated them.Moreover, the processing of COSMO-SkyMed (CSK) and Sentinel intensity data will be carried out to determine if the most relevant extracted features match those visible on high-resolution Digital Elevation Models from Airborne photogrammetry and Lidar Surveying. This analysis is also devoted to understand how SAR observation capabilities vary with sensor resolution, geometric distortion and surface roughness.

Space exploration rovers are designed to investigate the surface of celestial bodies in the Solar System, seeking habitability conditions and biosignatures. These vehicles are equipped with instrumentation and sensors that allow accomplishing in-situ operations. To increase their access capability to harsh environments, onboard systems are included to enable obstacle avoidance and slip prediction that represent fundamental functionalities for safe navigation. This work focuses on the implementation of a method that accurately reproduces the wheel-soil interaction and predicts rovers' performances in different scenarios (e.g., cloddy/drift terrain type, steep terrains). We implemented a 3D model of a rover to simulate its navigation with obstacles on the path. Our estimated trajectory is obtained through the Light Detection And Ranging (LIDAR) data processing, which enables the simultaneous localization and mapping (SLAM).

The exploration of planetary surfaces with unmanned wheeled vehicles will require sophisticated software for guidance, navigation and control. Future missions will be designed to study harsh environments that are characterized by rough terrains and extreme conditions. An accurate knowledge of the trajectory of planetary rovers is fundamental to accomplish the scientific goals of these missions. This paper presents a method to improve rover localization through the processing of wheel odometry (WO) and inertial measurement unit (IMU) data only. By accurately defining the dynamic model of both a rover’s wheels and the terrain, we provide a model-based estimate of the wheel slippage to correct the WO measurements. Numerical simulations are carried out to better understand the evolution of the rover’s trajectory across different terrain types and to determine the benefits of the proposed WO correction method.

The future robotic exploration of planetary surfaces will require autonomous and safe operations to accomplish outstanding scientific objectives. The main goal of space robotic systems consists in expanding our access capability to harsh environments in the solar system (e.g., Martian polar caps, icy moons). However, the operations of systems onboard landers and rovers are still mainly commanded and controlled by ground operators. To enhance the efficiency of future rovers, we are developing a robust guidance, navigation and control system that enables safe mobility on different terrain and slopes conditions, including the presence of obstacles.High slippery terrains, such as sandy-loose soils, could prevent the rover locomotion, affecting its safety. Furthermore, the presence of these demanding terrains may impact on the rover navigation, leading to inaccuracies in the Wheel Odometry (WO) measurements because of wheels’ loss of traction. Therefore, we implemented a navigation algorithm based on Visual Odometry (VO) that is the technique based on the processing of stereo-camera images captured at successive times during the vehicle’s motion. This method is fundamental to help WO during operations that require fast responses and high-accurate positioning. We also adopted a LIDAR sensor to improve the position estimate accuracy by processing measurements associated with well-known terrain features.We present here numerical simulations of rover navigation across different terrain conditions by using accurate dynamical models, including the deformability of both wheel and terrain. VO and LIDAR data are simulated and processed to determine the positioning accuracies that enable safe navigation. The results are in full agreement with the existing (i.e., Mars Exploration Rovers (MER)) and future (i.e., ExoMars) rover performances. Our algorithm allows reconstructing the rover trajectory with higher accuracies compared to the localization system requirement of the NASA MER rovers (i.e., 10% error over 100 meters traverse).

Parotid glands from adult dogs were stained with a battery of seven horseradish peroxidase-conjugated lectins (PNA, UEA, LTA, DBA, SBA, WGA and ConA). In some cases (PNA and DBA) neuraminidase digestion was followed by lectin staining. Acinar cells contained conspicuous quantities of oligosaccharides with terminal sialic acid radicals. Galactosil-(beta 1--3) N-acetylgalactosamine was the most abundant penultimate sugar linked to N-acetylneuraminic acid. Sialylated components having the terminal dimer sialic acid-N-acetylgalactosamine were found in the acinar cells. Secretory cells presented a heterogeneous distribution of glycoconjugates with terminal fucose and beta-N-acetylgalactosamine. Fucose, N-acetylglucosamine and alpha-N-acetylgalactosamine were present on the apical cytoplasm and surface of the striated and interlobular duct cells. This glycosidic composition was unaffected by extensive selective breeding. The role of abundant amounts of sialic acid radicals in the oral mucosa was considered.

Bovine lingual glands consist of mucous acini capped by demilunes. Information on the chemical structure of their secretory glycoconjugates was obtained by means of a battery of peroxidase-conjugated lectins with affinity for specific terminal sugars. Sialidase procedures followed by lectin staining were also used to visualize the sugar sequences. Stored secretions in mucous acinar cells contained fucose, N-acetylglucosamine, alpha and beta-N-acetylgalactosamine as terminal sugar residues and beta-galactose as penultimate sugar in a heterogeneous distribution. Demilunar cells failed to react with any of the lectins examined except that of Dolichos biflorus.

The biological behavior of the pigmentary phenotypes of four breeds of cattle has been analysed: the black pigmentation of Holstein Friesian; the red pigmentation of Limousin; the dilution in Charolais; and the postnatal disappearance of red pigmentation in Chianina. The analytic techniques included the characterization of melanins by high-performance liquid chromatography, the examination of follicular melanocytes by light microscopy, and the examination of melanosomes by electron microscopy. The black phenotype was very strongly eumelanogenic. The red phenotype in Limousin is polymorphic: individual follicular melanocytes contain both mature eumelanosomes and pheomelanosomes. Charolais and Chianina cattle exhibited a dramatic reduction in melanogenic activity, which was characterized by the almost exclusive presence of prephaoemelanosomes in Charolais and of immature premelanosomes in Chianina. In the dilute Charolais phenotype, the density of distribution of follicular melanocytes also seemed to be reduced. The genes that are responsible for these four phenotypes seem to act on the maturation, differentiation, and density of distribution of the melanosomes.

The glycoconjugate content of major horse salivary glands was investigated by means of horseradish peroxidase-conjugated lectins. Qualitative differences were observed in the terminal sugar residues of secretory glycoproteins and glycoconjugates linked to the apical surface of excretory duct epithelial cells. Mucous acinar cells in mandibular and sublingual glands contained oligosaccharides with D-galactose, alpha- and beta-N-acetylgalactosamine, N-acetylglucosamine and fucose residues, whereas mandibular, sublingual and parotid serous cells contained only oligosaccharides with terminal alpha- and beta-N-acetylgalactosamine residues. The apical portion of striated and interlobular duct lining cells of mandibular and sublingual glands stained for alpha- and beta-N-acetylgalactosamine and for N-acetylglucosamine. In parotid gland the cytoplasm of intercalated duct cells and the apical surface of striated duct epithelial cells stained for alpha-N-acetylgalactosamine.

It is widely documented that a pool of multipotent stem cells located in humans and mice hair follicle outer root sheath (bulge region) is involved in the restoration of the whole follicular unit during each anagen phase. To the authors' knowledge, data regarding the location and characterization of hair follicle stem compartment in dogs have not been reported in the recent relevant literature. In this study, we investigated the haematopoietic stem and progenitor cell antigen CD34 as a marker of putative stem cells located in a bulge-like region of canine hair follicles. The presence of CD34 mRNA and glycoprotein was assessed on formalin-fixed, paraffin-embedded canine skin samples by in situ hybridization technique and by standard immunohistochemistry, respectively. A strong expression of CD34 mRNA and glycoprotein was observed in a well-defined area of the hair follicle isthmic region and appeared uniformly concentrated at the level of the basal layer of the outer root sheath. These findings provide compelling support to the hypothesis that in dogs, a subpopulation of basal keratinocytes located in the hair follicle isthmic region and characterized by the selective expression of CD34 is potentially associated with the stem cell compartment of this skin appendage.

The glycosoaminoglycans in the digestive apparatus of immature fish have important biological functions and are involved in morphofunctional differentiation. The aim of this study was to investigate the glycoconjugate histochemistry in the different parts of the digestive apparatus (oesophagus, stomach, intestine) of Umbrina cirrosa (L.) fry using classical histochemical reactions (periodic acid-Schiff, Alcian blue pH 2.5, Alcian blue/periodic acid-Schiff, high iron diamine, low iron diamine) in conjunction with glycolytic digestions that degrade different classes of glycosoaminoglycans. No differences were observed in the reactivity to conventional histochemical staining of the oesophagus, stomach or intestine among 27-, 34- or 44-day-old fry. In the oesophagus, the mucopolysaccharides contained chondroitin sulphates B and A and/or C, heparan sulphate and chondroitin. In the stomach, only neutral glycoconjugates were revealed, whereas in the intestine there were only chondroitin sulphates. Some differences in the type and content of glycoconjugates were found in Umbrina cirrosa (L.) fry compared to those of adult subjects, probably related to different dietary habits and to changes in the environmental conditions.

Analysis of melanins and melanosomes in eight hair and skin samples taken of adult pigmented Argentine llamas (Lama glama L.) has been carried out. In each sample, eumelanins, pheomelanins and alkali-soluble melanins were identified. The total amount of melanins and the amount of eumelanins both decreased from black to reddish brown colour, while pheomelanins were found to be present in small quantities in each sample. Eumelanosomes were round and oval-shaped, displaying transverse striations clearly visible at low magnification. Dark brown samples revealed all four melanosomes stages. Stages I and II melanosomes appeared as large, asymmetrical vacuoles containing numerous microvesicles randomly scattered within an amorphous proteinaceous material (vesiculo-globular bodies). Stage III melanosomes had microgranular melanin deposits in the microvesicles and in the matrix. The fully melanized melanosomes (stage IV) were primarily round-shaped, showing an irregular outline and the electron-dense pigment was arranged to form large clusters. In light brown melanocytes, numerous melanosomes at different maturation stages could be found. Premelanosomes appeared ovoid, containing amorphous proteinaceous material and spotty and microgranular deposits. Mature melanosomes were fully melanized, homogeneously electron-dense, ovoid granules.

Summary The presence and distribution of serotonin-containing cells in the gastroenteric tract of horses have been investigated. The enterochromaffin (EC) cells have been identified using immunostaining procedures at both light and electron microscopic level. The EC cells were very numerous in the pyloric gland region, were only few in the duodenum but were absolutely lacking from the more distal portions of the intestine.

Summary In order to elucidate the carbohydrate profile of the mucosa of lamb duodenum, conventional histochemical methods and a panel of 7 labelled lectins were used. In some cases, treatment with sialidase preceeded lectin staining. Carbohydrate histochemistry revealed the presence of sugar residues in the brush border of enterocytes, goblet cells and duodenal glands. All sites contained neutral and acid glycoconjugates. The presence of sulphomucins in goblet and duodenal gland cells was age-dependent. Enterocytes and duodenal gland cells contained abundant amounts of oligosaccharides with terminal sialic acid-galactosyl(β1 → 3)N-acetylgalactosamine, whereas goblet cells contained the penultimate N-acetylgalactosamine residue linked to sialic acid. These findings were not age-dependent, whereas scarce amounts of fucose were found in all sites especially in young animals. The findings obtained in the present study serve as a basis for future pathological studies in lamb and sheep.

The chemical content of the secretion of the sheep lacrimal gland was analysed at the light and electron microscope levels by applying histochemical techniques and an ultrastructural histochemical method (periodic acid, thiocarbohydrazide and silver proteinate). Mucosubstance histochemistry demonstrated acidic glycoconjugates, mainly sulphated, in the mucous and seromucous glandular cells and in the apical portion of the cells lining the terminal ducts. Moreover, secretory granules, stained with PA-TCH-SP, showed a different localization of the reaction product. The presence of lysozyme was also found in the glandular serous cells. These histochemical studies demonstrate that the secretion of sheep lacrimal glands is mixed, having serous, mucous and seromucous components, and that an excellent correlation exists between the secretory granule substructure and glycoprotein localization.

The gastroenteropancreatic endocrine system was studied in 11- and 17-week-old fallow deer foetuses using an immunocytochemical technique. In the gastrointestinal tract, gastrin-, serotonin-, somatostatin- and cholecystokinin-containing cells were found: their frequency and distribution were also determined. Anti-glucagon and anti-insulin antibodies did not stain any cells along the gut. In the pancreas, somatostatin-, pancreatic polypeptide-, insulin- and glucagon-immunoreactive cells were detected. The different distribution and number of neuroendocrine cells, in the two investigated stages of foetal life, are discussed. Data obtained in this study were compared with those published in a previous study on the gastrointestinal system of the adult fallow deer.

Summary The morphology of the intestine has been studied in a species of warm water fish, Tilapia spp., a hybrid teleost of notable economic importance. Light and electron microscope results show that the intestine is a relatively undifferentiated muscular tube lined with a simple columnar epithelium interspersed with goblet cells. The proximal region has a greater surface area, manifested by elongated mucosal ridges. The enterocytes are covered apically with uniform microvilli and exhibit the typical ultrastructural features of pinocytosis, namely extensive invaginations of the luminal plasma membrane and massive accumulation of vesicles in the apical cytoplasm. The distal intestine mucosa is thinner and less elaborately folded and consists of columnar cells with shorter and sparser microvilli. Their supranuclear cytoplasm contains abundant clear vacuoles. Numerous endocrine cells can also be seen. Regional cellular ultrastructural features are correlated with digestive functions.

Summary The Bovine tongue possesses numerous circumvallate papillae (8–16) each side). The troughs around the papillae are the openings of the ducts of the gustatory (von Ebner's) glands. In this study, we have characterized in situ the glycosidic composition of the secretion of bovine gustatory glands using traditional histochemical methods and lectin histochemistry with and without prior neuraminidase (sialidase) digestion. The lectin-horseradish peroxidase conjugates employed were: PNA, DBA, SBA, WGA, LTA, UEA I and ConA. Acinar cells show a diffuse positivity towards PAS and Alcian blue at pH 2.5 and the most intense and homogeneous lectin staining was obtained with PNA. This indicates that bovine gustatory glands secrete glycoproteins with 1,2-glycol containing hexoses and carboxyl-rich glycoconjugates and that galactosyl (β1 3) Nacetylgalactosamine is the most frequent sugar residue present in these glycoproteins. Results were compared with data reported in the literature on the same glands of other species.

Summary The sugar residues in glycoconjugates present in the parotid and mandibular glandsof the adult fallow-deer were detected and characterized by using a battery of eight different lectin-horseradish peroxidase conjugates. In some cases a treatment with sialidase preceded the lectin staining. Parotid secretory cells produced glycoconjugates with N-acetylgalactosamine, N-acetylglucosamine and mannose residues. Mucous acinar cells were the most reactive sites of the mandibular gland and contained conspicuous quantities of oligosaccharides with terminal sialic acid radicals. Galact0sil-(β1 → 3)N-acetylgalactosamine was the most abundant penultimate sugar linked to N-acetylneuraminic acid. Mandibular mucous cells also presented N-acetylglucosamine and sialylated components with the terminal dimer sialic acid-N-acetylgalactosamine. Demilunar cells contained glycoconjugates with fucose and mannose residues. The apical surface of duct cells was stained by all the lectins.

Summary An ultrastructural study has been made of gastric mucosa of a teleostean fish, Tilapia spp. The cytological features of the surface mucous cells, mucous neck cells, glandular cells and endocrine cells are described. The surface mucous cells, identified by their superficial localization, are characterized by apical granules. The mucous neck cells are distinguished by the appearance of their mucous granules and their localization between surface mucous cells and glandular cells. The gastric glands contain only one form of cell whose fine structure is similar to cells that secrete hydrochloric acid. Physiological implications of some ultrastructural features are also discussed.

The proximal and interlobular ducts of rabbit zygomatic glands show a particular morphological feature consisting of numerous secretory granules localized in the apical cytoplasm of the cells. It is suggested that there is a similarity between these ducts and the granular ducts of submandibular glands in rodents.

Summary Endocrine cells were detected in the gastro-enteric tract of the fallow deer by means of immunohistochemical procedures, using antibodies against serotonin, somatostatin, gastrin, glucagon and cholecystokinin. The number of cells positive for each antiserum in each region was evaluated. Serotonin-containing enterochromaffin (Ec) cells were present in every region investigated and were most numerous in the proximal duodenum. Cells positive for somatostatin were present in all the regions studied, with the exception of the colon, and were especially numerous in the proper gastric-gland region. Cells that were stained by the anti-gastrin antibody were very numerous in the pyloric-gland region but only rare in the duodenum. Glucagon-immunoreactive cells were only detected in the large intestine and their frequency was always less than 10/0.5 mm2. Cholecystokinin-containing cells were scarce and restricted to the pyloric-gland region and duodenum.

In the present work, gustatory glands (von Ebner's glands) of the horse tongue were examined by means of five peroxidase-conjugated lectins (PNA, DBA, SBA, UEA I, WGA), with and without prior sialidase digestion, in order to investigate the presence and distribution of carbohydrate residues in secretory cells and duct cells. The most intense staining of secretory cells was observed with PNA after pre-treatment with neuraminidase. This indicates that the terminal trisaccharide sequence sialic acid- (alpha 2-->3, 6) galactosyl (beta 1-->3) N-acetylgalactosamine is the most frequent oligosaccharide chain present in glycoproteins secreted by horse gustatory glands. Secretory cells also contained oligosaccharides with terminal alpha-N-acetylgalactosamine and N-acetylglucosamine, whereas fucose was found in only a few glandular cells. The apical cytoplasm of duct lining cells reacted with all the lectins except WGA.

Seven lectins (PNA, DBA, SBA, UEA I, LTA, WGA and ConA), conjugated with horseradish peroxidase, were used to characterize the glycosidic residues in the zygomatic gland of adult dogs. In some cases (PNA and DBA), lectin staining was preceded by neuraminidase digestion. The acinar and tubular cells produced glycoconjugates with different sugar residues, presenting binding sites for all of the lectins used. The apical surfaces of the cells lining the intra- and interlobular ducts were also stained by all the lectins. In contrast, the demilunar cells only reacted with the Neu-PNA sequence and Con A.

Summary The secretory process in swine apocrine sweat glands were studied by electron microscope. The sweat appeared to result from three different mechanisms: (a) fluid transport, probably involving a region of complex cellular interdigitations adjacent to the basement membrane, (b) exocytosis of vesicles, which in this species seem to be derived from the Golgi apparatus and finally (c) apocrine secretion.

In esemplari di Dugesia lugubris e stata esaminata I'ultrastruttura nel neurosecreto delle fibre nervose decorrenti fra i fasci ghiandolari faringei di soggetti digiuni da 7 gg e di soggetti utilizzati nel momento dell'assunzione del cibo. Nei digiuni il neurosecreto e abbondante in vicinanza delle propaggini ghiandolari e molto scarso in prossimita dei corpi delle ghiandole. Negli alimentati il neurosecreto e scarso a livello delle propaggini ed abbondante in prossimita dei corpi ghiandolari. In base a questi rilievi si avanza l'ipotesi che esista una precisa correlazione fra neurosecreto e secreto ghiandolare.

1. 1. In 24 hr regenerating planarians the N-acetyl-β-d-glucosaminidase (EC 3.2.1.0) is localized in the lysosomes of dediffenentiating cells. 2. 2. The N-acetylglucosaminidase localization in dedifferentiating cells, correlated with the increase in N-acetylglucosaminidase and N-acetylgalactosaminidase activities during the first 24 hr of regeneration, confirms the involvement of the dedifferentiation in the origin of blastema. 3. 3. In non regenerating animals the N-acetylglucosaminidase activity has been cytochemically demonstrated in the lysosomes of gastrodermal cells and in the mucous granules of basophilic secretory cells. This latter finding is interpreted as proof of a similarity between planarian and vertebrate mucous secretion.

Prostaglandin dehydrogenase activity is histochemically detected in various bovine tissues (kidney, liver, lung, parotid and naso-labial glands) using as substrate prostaglandin F-2 alpha. Kidney, liver and lung showed the highest intensity of the reaction, but parotid and naso-labial glands also displayed enzymatic activity at the level of the ductal cells.

In the testis of Esox lucius at the time of spermiation, activity of cyclic adenosine 3',5'-monophosphate (cAMP) was immunocytochemically localized at the level of the Sertoli cells. In these cells adenylate cyclase activity was also ultracytochemically demonstrated by using adenylyl imidodiphosphate as a substrate. Reaction products of adenylate cyclase were primarily detectable on the basal and adluminal plasma membranes and on the surface of protrusions of the cell body into the lumen.

Cytochemical studies of adenylate cyclase activity were performed on Dugesia lugubris s.l. to ascertain which cell types, among the heterogenous cell population, showed significant adenylate cyclase activity on their plasma membranes. Nondecapitated worms and cephalic regenerants were examined in replicated experiments. Evidence of adenylate cyclase activity was noted in secretory tissues and the protonephridial system of non-operated worms, and also in dedifferen-tiating and regenerating tissues of operated worms. Observations presented in this study call attention to the role of adenylate cyclase in some of the main physiological processes of triclads, such as secretion, excretion, and regeneration.

The localization of adenylate-cyclase activity in Dugesia lugubris s.1. has been investigated cytochemically using 5'-adenylyl-imidodiphosphate as substrate. The enzyme was localized in mucous gland cells, in rhabdite cells, in intercellular spaces and also in nerve endings of this planarian. The presence of adenylate-cyclase on the membrane suggests that it might mediate different stimulus-secretion coupling by increasing cyclic AMP synthesis in specialized areas of the planarian.

Summary The morphological differences between two types of secretory cells (clear and dark) from pig carpal glands were examined. The main difference is the presence in the dark cells of secretory granules of moderate electron density, made up of acidic and neutral glycoproteins. The possible functional purposes of the carpal glands and of glycogen present in both cell types are also discussed.