Portion Of Margin Research Articles

New sites expanding the “Sardinian cold‐water coral province” extension: A new potential cold‐water coral network?

Abstract Cold‐water coral (CWC) ecosystems are protected both in national and international waters. They are considered Vulnerable Marine Ecosystems and, in addition, meet the criteria to be defined ecological or biological significant areas. Two new sites of the “Sardinian CWC province” were discovered by means of remotely operated vehicle surveys in two submarine canyons in the north‐eastern portion of the Sardinian continental margin, at depths ranging from 230 to 430 m. Dense and healthy patches of small and medium‐sized Madrepora oculata colonies were found dwelling on rocky walls and inclined silted soft bottoms. A rich and diverse associated megafauna was found within both live and dead portions of the coral framework. In addition, the presence of benthic litter and derelict fishing gears were also documented. These results further extend the “Sardinian CWC province” extension, providing insights of a potential CWC network along the Sardinian continental margin with implications for the Mediterranean mosaic of CWC provinces, further stressing the need for urgent conservation measures for these habitats.

Upper Extremity Injuries in Soccer.

Upper limb injuries in soccer represent only a marginal portion of injuries, however this is mainly true for outfield players. Goalkeepers are reported to have up to 5 times more upper extremity injuries, many of them requiring substantial time-loss for treatment and rehabilitation. The most common upper extremity injury locations are the shoulder/clavicle followed by the hand/finger/thumb, elbow, wrist, forearm, and upper arm. The mechanism of injury, presentation, physical examination, and imaging features all play a significant role in reaching the correct diagnosis. Taking to consideration the position the player plays and his demands will also enable tailoring the optimal treatment plan that allows timely and safe return to play. This article discusses common upper extremity injuries observed in soccer players, focusing on proper diagnosis and optimal management.

Prevalence and location of bone spurs in anterior ankle impingement: A cadaveric investigation.

Anterior ankle impingement (AAI) results from repetitive microtrauma leading to pain and decreased dorsiflexion due to spur formation and synovial hypertrophy. Information about the prevalence of anterior spur formation in a large population, and the individual contributions of the talus and tibia to osseous impingement, is limited. A total of 670 ankle specimens from 344 individuals (n = 111 females, n = 233 males) aged 20 to 40 years at the time of death were examined. Matching tibia and talus were opposed and any spurring causing impingement was recorded. Spur locations were measured and ratios calculated to allow for inter-specimen comparison between: (1) medial-to-lateral and anterior-to-posterior spur location versus dimensions of talar neck width, and (2) medial-to-lateral spur location to dimensions of distal anterior tibial width. Differences in spur prevalence in relation to sex, race, height and age were identified by univariant and multivariable statistical analyses. Bony impingement was observed in 21% (n = 72) of specimens, with bilateral involvement in 8% (n = 27). For ankles with AAI, spurs were seen on the talus only in 61%, on the tibia only in 14%, and on both the tibia and talus in 26%. Spurs were significantly more prevalent in males (P = 0.001) and with increasing specimen age (P = 0.002). There were no significant differences related to specimen height or race. Spurs were predominately located on the anterolateral talus (78%) and the anterolateral portion of the distal tibial margin (80%). AAI was present in 21% of young osseous specimens and was significantly more prevalent in males and with increasing specimen age. Clin. Anat. 31:1144-1150, 2018. © 2018 Wiley Periodicals, Inc.

Abstract 556: Intramyocardial EphrinA1-Fc Preserves Mitochondrial Structure and Bioenergetics Post-Myocardial Infarction

EphrinA1, a receptor tyrosine kinase ligand expressed in the plasma membrane of healthy cardiomyocytes, is reduced following acute myocardial ischemia (I)/reperfusion (R) injury in mice. Intramyocardial injection of recombinant EphrinA1-Fc at the time of LAD ligation attenuated infarct injury by 46% and completely preserved cardiac function in I/R (30min I/24hrs R). This was accompanied by reduced inflammation, attenuation of apoptosis, enhanced autophagy, and modulation of metabolic pathways that promote more efficient energy utilization. To examine the mechanism by which this occurs, mitochondrial structure and function was examined in 10 wk-old B6129SF2/J male mice given intramyocardial EphrinA1-Fc or IgG-Fc at LAD occlusion and subsequently reperfused for 24hrs. Permeabilized cardiac muscle fibers were isolated from a portion of the infarct margin of the left ventricle to assess mitochondrial function and energetics. EphrinA1-Fc prevented the 30% loss (p<0.005) in mitochondrial respiratory capacity in the absence of changes in H 2 O 2 emitting potential. Moreover, using a titrated creatine kinase energetic clamp, we found that EphrinA1-Fc improved the mitochondrial thermodynamic force-flow relationship by increasing OXPHOS conductance (+55% vmax, p<0.005), without changes in ADP affinity. Another small portion of the infarct margin was fixed and processed for transmission electron microscopy imaging which revealed that EphrinA1-Fc treatment prevented the MI-induced loss of sarcomere alignment and mitochondrial organization along the Z disks, as well as disorganization of the cristae. There was also significantly less lipid droplet accumulation and preservation of intermitochondrial junctions. Morphometric analyses of mitochondria are in progress as are Western blot assays to identify the proteins involved. Myocardial strain analyses are also underway to explore and pinpoint regional changes in contractile function. Collectively, these data demonstrate that intramyocardial injection of EphrinA1-Fc attenuates I/R injury by preserving the mitochondrial network structure and bioenergetic capacity. The robust cardioprotection afforded by ephrinA1-Fc offers promise as a novel therapeutic for the treatment of acute MI.

Differentiated Mafic–Ultramafic Intrusions of the Kruglogorsky Type in the Noril’sk Area: Petrology and Ore Potential

Intrusions of the Kruglogorsky type are an integral part of magmatic formations in the Noril’sk area. The marginal portions of these intrusions are composed of microdolerite, dolerite, and contact gabbrodolerite. The central parts of the intrusions consist of leucogabbro and of olivine-free, olivine-bearing, and olivine gabbro-dolerite. Leucogabbro is a characteristic rock of this type of intrusions and sometimes composes up to half of the thicknesses of the rock units. The rocks with plagioporphyritic textures are widespread. Olivine-free, olivine-bearing, and olivine gabbro-dolerite occur as horizons with indistinct boundaries, which are unevenly distributed over the vertical sections of the lithological units. The olivine is the most magnesian (Fo89-64) and richest in Ni (up to 0.23 wt % NiO) in the olivine gabbro-dolerite. The clinopyroxene is represented by augite (Fs12-29). The rock-forming minerals are typically zoned. The Sr isotopic composition of the rocks (calculated for an age of 250 Ma) varies within a considerable range (87Sr/86Sr = 0.705972–0.708006), due to metasomatic alterations. The variations in the Nd and Sr isotopic composition of the Kruglogorsky intrusion are close to those in rocks of the Noril’sk-type ore-bearing intrusions. The olivine-bearing and taxitic gabbro-dolerite host Pt–Cu–Ni ore mineralization, which are of economic value for disseminated ores of the Talnakh area.

Conceptual model of the Tatun geothermal system, Taiwan

The Tatun geothermal system, located in northern Taiwan, is hosted by the Plio-Pleistocene Tatun volcanic group, consisting dominantly of andesitic lavas, domes and pyroclastic flows. During the late 1960s and early 1970s, geologic mapping, geochemical sampling, geophysical surveys, and the drilling of numerous exploration and temperature gradient wells were conducted at Tatun under the leadership of the Mineral Research and Service Organization (MRSO), the predecessor to the geothermal group at the Industrial Technology Research Institute (ITRI). Deep (1–2 km) wells encountered commercial temperatures (200–300 °C) in the Matsao area, but these initial exploration efforts were discouraged by the presence of very acidic (pH <3.5) and highly corrosive fluids. Numerous geoscience studies conducted over the past 15 years at Tatun have shown that the central portion of the system is dominated by corrosive volcanic fluids, as evidenced by abundant SO2 as well as HCl. More reduced gases are encountered on the flanks of the system, suggesting that water-rock interaction may have at least partly neutralized the volcanic-derived fluids on the margins of this geothermal system.Scientists from Lawrence Berkeley National Laboratory (LBNL) and ITRI have been working together to develop an updated evaluation of the Tatun geothermal system, with the goal of evaluating the geothermal resource potential of the NE margins of the Tatun geothermal system (Zone C), just outside of Yangmingshan National Park. This study provides a review and analysis of existing and new fluid geochemistry data, describes new magnetotelluric data and associated 3-D modeling conducted at LBNL, and incorporates these data and analyses with information from previous studies to create an updated conceptual model for the Tatun geothermal system, with a focus on the Zone C region. These data all suggest that the Zone C area is located on the margin of the main Tatun geothermal system. An exploration well drilled by ITRI will provide important constraints regarding the thermal regime and fluid compositions for this marginal portion of the system.

Pulse wave Doppler ultrasound of testicular arteries and their relationship with semen characteristics in healthy bulls

BackgroundSemen evaluation is used to estimate the testicular function. In bulls, the spermatozoa present in the ejaculate are the result of a process that begun more than 2 mo earlier, bequeathing a delayed depiction of the actual function of the testis. Since testis vascularization might be critical for the gonad function, selected pulse wave Doppler ultrasound parameters were assessed in this study, for instance the peak systolic velocity, the end diastolic velocity and the resistive index of the testicular artery along the spermatic cord, the marginal portion of the testicular artery and the intratesticular branches of the testicular artery both in healthy adult and young bulls. Correlations between these parameters and characteristics of semen that was collected numerous times, before and after the Doppler ultrasound examination.ResultsThe peak systolic velocity and the end diastolic velocity measured in the testicular artery along the spermatic cord (supratesticular artery – SA) were variable among the bulls and within individual bulls, likely due to the convoluted course of the vessel. The resistive index was found highly repeatable in the same bull. A reduction in the resistive index was found between the supratesticular artery and the marginal portion of the testicular artery (P < 0.01), and between the marginal portion of the testicular artery and the intratesticular branches of the testicular artery (P < 0.05). No differences were recorded for the pulse wave Doppler ultrasound parameters in young bulls compared with adults. A significant correlation was found between the resistive index of the marginal portion of the testicular artery and total sperm in the ejaculate (r = 0.516, P < 0.05), the immature sperm (r = 0.462, P < 0.05), the teratoid sperm (r = 0.375, P < 0.05), and the “Dag defect” sperm (r = 0.389, P < 0.05). Similarly, the resistive index of the intratesticular branches of the testicular artery were found correlated with the total sperm number in the ejaculate (r = 0.568, P < 0.05), the immature sperm (r = 0.523, P < 0.05), the teratoid sperm (r = 0.418, P < 0.05), and the “Dag defect” sperm (r = 0.341, P < 0.05).ConclusionsThe data presented in this study suggest that the resistive index, measured at the marginal portion of the testicular artery, could be an easy-to-perform parameter to evaluate the spermatogenesis quality in young bulls and normal adults.

Phases or regimes? Revisiting NDVI trends as proxies for land degradation

AbstractOne of the main challenges in land degradation assessment is that a rigorous and systematic approach to addressing its complex dynamics is still missing. The development and application of operative tools at regional and global scales remain a challenge. Land degradation is usually defined as a long‐term decline in ecosystem function and productivity. Due to its temporal and spatial resolution as well as data availability, the use of time series of spectral vegetation indexes obtained from satellite sensors has become frequent in recent studies in this field. Slope of linear trends of the normalized difference vegetation index is usually considered an accurate indicator and is widely used as a proxy for land degradation. Yet this method is built on a number of simplifying conceptual and methodological assumptions that prevent capturing more complex dynamics, such as cyclic or periodic behaviors. Our aim was to examine the limitations associated with using linear normalized difference vegetation index trends as proxies for land degradation by comparing outcomes with an alternative methodological procedure based on wavelet autoregressive methods. We explored these issues in 5 case studies from Africa and South America. We observed that trend explained a marginal portion of total temporal variability, whereas monotonic functions, such as linear trends, were unable to capture dynamics that were non‐unidirectional, resulting in misinterpretation of actual trends. Wavelet autoregressive method results were encouraging as a step towards the application of more accurate methods to provide sound scientific information of land degradation and restoration.

Modified second stage Hughes tarsoconjunctival reconstruction for lower eyelid defects

ABSTRACTTo describe a novel technique utilizing an amniotic membrane graft (AMT) to create the mucocutaneous portion of the lower eyelid margin in a modified Hughes eyelid reconstruction for secondary revision or prevention of a hyperemic, hypertrophic conjunctival margin with excessive discharge. This was a retrospective, non-comparative interventional study. Thirty consecutive patients who underwent a modified Hughes reconstruction were included. The first step of the reconstruction was performed in a standard fashion using a tarsoconjunctival flap from the ipsilateral upper eyelid. The second stage was accomplished by the division of the tarsoconjunctival flap. The modification of the procedure included the addition of AMT (Ambio 5®, IOP Ophthalmics, CA) to the new mucocutaneous junction. Main outcome measures included the post Mohs surgery defect size, post-reconstruction complications. One patient received AMT for a revision of a hyperemic lid margin following reconstruction, while 29 subsequent patients received AMT as a primary procedure. The mean size of the post-Mohs defect was 23.75 ± 6.6 mm2 horizontally and 9.1 ± 5.4 mm2 vertically, involving 79.53 ± 16.8% of the lower eyelid. There was no evidence of hyperemic or hypertrophic margin at a mean follow-up of 4.41 ± 2.91 months. The addition of an AMT for the revision, or as a primary procedure for prevention of a hyperemic, hypertrophic eyelid margin with excess mucus production in the post-Hughes lower eyelid reconstruction has favorable outcomes in this preliminary study, however warrants further investigation with larger number of patients and longer follow-up.

Marginal facies and compositional equivalents of Bushveld parental sills from the Molopo Farms Complex layered intrusion, Botswana: Petrogenetic and mineralization implications

The composition of magmas considered to be parental to layered ultramafic to mafic intrusions are commonly studied using rocks occurring along their marginal portion, in contact with the surrounding country rock. With a size, approximately 1/3rd of the ∼2.05 Ga Bushveld Complex layered intrusion, mafic to ultramafic rocks of the Molopo Farms Complex in Botswana are suggested to have formed from the same magma that formed the Bushveld rocks. Of the different drill cores available, the base of MF38 intersects the country rock. Two other drill cores, MF9 and MF11, were also logged for comparison. Drill core MF38 preserves remobilized country rock at the base, followed up by mafic (norite) to ultramafic (peridotite-pyroxenite) rocks. The norite is quench textured with elongate, skeletal, compositionally zoned orthopyroxene crystals, and contain phlogopite. Significantly, the orthopyroxene mineral chemical composition is similar to that reported for chill margin from the Bushveld Complex. Together with the remobilized country rock beneath, norite at the base of drill core MF38 is interpreted to represent a marginal facies unit. The whole-rock geochemical characteristics of the marginal facies norite are similar to those of chill margin and B1 compositions from the Bushveld Complex, arguing for it to represent the earliest known parental magma composition to the Molopo Farms Complex. A medium-grained phlogopite-bearing pyroxenite occurring higher up the stratigraphy in drill core MF38 is considered compositional equivalent to B1UM from the Bushveld Complex. Further, the whole-rock geochemical characteristics of gabbronorites from drill core MF9 are comparable to B3, considered parental to differentiated end members of the Bushveld Complex. No compositional equivalent to B2 from the Bushveld Complex was observed in the Molopo Farms Complex rocks. Considering the fact that the Molopo Farms Complex is less thick than the Bushveld Complex, and that it preserves mafic and ultramafic rocks showing similarity to the earliest magma (B1, B1UM and chill margins) as well as the most differentiated of the Bushveld magma (B3), it is argued that the Molopo Farms Complex evolved faster. Thus it likely did not form rocks of the Bushveld Complex, which hosts the chromite-bearing layers, known for PGE mineralization. Instead, it is argued that the Molopo Farms Complex is a better target for Cu-Ni sulphide mineralization. A possible sulphide genesis model is presented in relation to the prominent occurrence of magmatic pyrrhotite-pentlandite-chalcopyrite assemblage in the studied rocks, trace amounts of PGM associated with sulphides in the marginal facies norite, and the alteration features associated with sulphides.

Origin of exotic clasts in the Central-Southern Apennines: clues to the Cenozoic fold-and-thrust collisional belt in the Central Mediterranean area

AbstractThe Central-Southern Apennines are the result of the collision between Europe and Africa. Despite the volume of existing literature, many problems remain unsolved such as the presence of Tertiary conglomerates containing exotic basement clasts. The lack of basement rocks in the Central-Southern Apennines implies that the origin of these clasts has to be sought in areas where the basement is extensively exposed. These include the Calabro–Peloritani arc and the Sardinia–Corsica block, which in Cenozoic time were connected to the Central-Southern Apennines. In this work we present the results of sedimentary, geochemical and petrographic analyses performed on the exotic basement-derived clasts. These analyses include lithological, major- and minor-element and rare Earth element compositions which are compared to analogous rocks from Calabria and Sardinia basements. Results indicate Eastern Sardinia as the primary source area for the studied conglomeratic units, linking the Central-Southern Apennines sedimentary cover to the Mesozoic carbonates of Eastern Sardinia prior to the opening of Tyrrhenian Sea. The Cilento unit (Campania) was directly fed by an uplifting Cenozoic orogen, and the Filettino, Gavignano (Latium) and Ariano Irpino (Campania) units were produced by the successive reworking of ‘Cilento-like’ sedimentary units. These results may imply that part of the Central-Southern Apennines represented a portion of the European margin of the Tethys.

Reply to Comments on “the Cenozoic Fold‐and‐Thrust Belt of Eastern Sardinia: Evidences from the Integration of Field Data With Numerically Balanced Geological Cross Section” by Arragoni et al. (2016)

AbstractThe comment by Berra et al. (2017) on the evidence of Alpine tectonics in Eastern Sardinia proposed by Arragoni et al. (2016) is based on the sedimentological interpretations of few local outcrops in a marginal portion of the study area. The Cenozoic Alpine fold‐and‐thrust setting, which characterizes this region, presents flat‐over‐flat shear planes acting along originally stratigraphic contacts, where stratigraphic continuity is obviously maintained. The ramp sectors present steeply dipping bedding attitudes, and there is no need to invoke and to force prograding clinoforms with unrealistic angles to justify them. The balanced geological cross section proposed by Arragoni et al. (2016) is fully supported by robust newly collected structural data and is compatible with the overall tectonic setting, while the interpretation proposed by Berra et al. (2017) lacks a detailed structural investigation. We believe that the partial application of the techniques available to modern geology may lead to incorrect interpretations, thus representing an obstacle for the progress of knowledge in the Earth sciences.

Energetics of the Brazil Current in the Rio Grande Cone region

The energetics of the Brazil Current (BC) in the region of the Rio Grande Cone (RGC, 30–35.5°S), a topographic rise in the southwest portion of the Brazilian continental margin, are analyzed using 16 years of numerical data from the Ocean General Circulation Model (OGCM) for the Earth Simulator (OFES). The main focus of this study is the eddy-mean flow interactions of the BC and the local energy budgets in the study region. The kinetic and potential energy balance equations are derived for mean and eddy flows, and the resulting terms are presented and discussed. The eddy-mean flow interactions exhibit complex spatial distributions, and the intensities of the energy budgets decrease with increasing depth. However, only the mean potential energy (MPE) budget decreases southward. Eddy kinetic energy (EKE) and eddy potential energy (EPE) exhibit similar horizontal distribution patterns. Additionally, the baroclinic and barotropic conversion rates increase downstream of the bump, where the eddy energy field exhibits along-stream variability that increases southward. Barotropic conversion is more intense between 50 and 200m, where mean kinetic energy (MKE) and EKE are concentrated, and it exhibits a horizontal cross-stream variation pattern, with mean-to-eddy energy conversion observed on the offshore side of the BC. This result indicates that the turbulence associated with the stream jet increases as the BC moves away from the coast, with the conversion term acting to stabilize the flow. Baroclinic conversion exhibits a high intensity below 300m (where MPE and EPE display peaks), and it has a greater influence on the eddy-mean flow interaction than does the barotropic conversion. The RGC directly affects the local dynamics of the BC by increasing the eddy field as soon as the BC reaches the bump. The energy diagrams illustrate a stream characterized by evolving barotropic and baroclinic instability processes throughout the water column. This result indicates an intrinsically unstable jet in the study region. Moreover, baroclinic instability is the main source of EKE in the RGC region.

Early Neoproterozoic arc magmatism of the Tongmuliang Group on the northwestern margin of the Yangtze Block: Implications for Rodinia assembly

The tectonic evolution of the Yangtze Block and its position in Rodinia during Neoproterozoic remain controversial for decades. One of the important reasons for the debates is the lack of late-Mesoproterozoic to early-Neoproterozoic arc volcanic rocks on the periphery of the Yangtze Block. In this study, we firstly report the spilite-keratophyre-quartz-keratophyre associations in the Tongmuliang Group on the northwestern margin of the Yangtze Block. LA-ICP-MS zircon U-Pb dating results indicate that they formed at ca. 970Ma and were possibly affected by Indosinian (ca. 235Ma) metamorphism. Most samples show strong enrichments in large ion lithophile elements and Pb and evident depletions in Nb, Ta and Ti, resembling typical arc-related magmatism. Moreover, their low Th/La, Nb/La and Nb/U ratios, as well as minor crustal incorporations, further define an intra-oceanic arc environment. The highly depleted whole-rock Nd and zircon Hf isotopes indicate that these rocks were originally derived from depleted mantle sources, while the Sr isotopes and Na concentrations may have been affected by post-condensation alteration. The spilites, metabasalts and keratophyres show similar La/Sm, Zr/Nb and Nb/La ratios and arc-like geochemical features, indicating a depleted mantle source that has been metasomatized by slab-derived fluids. The keratophyres were formed through fractional crystallization of primitive mafic magmas. However, the quartz-keratophyres were derived from partial melting of juvenile materials similar to the spilites and/or keratophyres. These observations led us to conclude that there was an ocean-ocean subduction along the northwestern margin of the Yangtze Block during early Neoproterozoic, corresponding to synchronous arc magmatism along the southeastern margin of the continent. Arc magmatism of this period on different portions of margins of the Yangtze Block may have experienced different processes.

Descriptions of eight new Acrogonia species from the Amazon region, including peculiar features of the female genitalia (Hemiptera: Cicadellidae: Cicadellinae: Proconiini).

Eight new species of the agriculturally important sharpshooter genus Acrogonia Stål, 1869 are described and illustrated from Brazil (one of them also recorded from Peru): A. amazonensis sp. nov. (state of Amazonas), A. clarae sp. nov. (states of Amazonas and Amapá), A. barbara sp. nov. (state of Mato Grosso), A. youngi sp. nov. (department of Madre de Dios in Peru and state of Acre), A. albertoi sp. nov. (state of Pará), A. tenuis sp. nov. (state of Mato Grosso), A. filiformis sp. nov. (states of Pará and Mato Grosso), and A. interrupta sp. nov. (state of Mato Grosso). In addition to the external morphology, color pattern and male genitalia, this paper includes detailed descriptions and illustrations of the female genitalia of three new species (A. barbara, A. filiformis and A. tenuis). The first ovipositor valvulae of A. tenuis are quite peculiar because they bear a large basal lobe and a projection on the median portion of the ventral margin, both displaying setae. Females of the other five new species are not known.

Evidence of hydrothermal fluid flow in a hyperextended rifted margin: the case study of the Err nappe (SE Switzerland)

This paper investigates hydrothermal fluid circulation in pre- and syn-tectonic sediments associated with detachments faults. The study area, located in the Err Nappe (SE-Switzerland), preserves a portion of the Adriatic distal margin. Two sites were studied in combining fieldwork, petrography, geochemistry and fluid inclusion analysis: the Piz Val Lunga and Fuorcla Cotschna areas. Both preserve relationships between a spectacularly exposed rift-related extensional detachment fault and its footwall and hangingwall that consist of extensional allochthons and syn- to post-tectonic sediments. These areas register a complex fluid flow history characterized by dolomitization, de-dolomitization, calcite cementation, dolomite and quartz veining and diffuse silicification. Meso- and micro-scale observations allow defining two steps in fluid evolution, which are related to Jurassic rift activity. A first carbonate-rich event occurred before the exhumation of the granitic basement, and this was followed by a second event marked by a change in the fluid towards a silica-dominated chemistry. Homogenization temperatures of fluid inclusions (average Th = 120−130 °C), negative δ18O values and a radiogenic 87Sr/86Sr signatures of carbonate minerals support the hypothesis that both the pre-tectonic rocks constituting the allochthons and the syn-tectonic sediments overlying the detachment fault were crossed by a flux of over-pressured hydrothermal fluids originating from seawater that penetrated into the basement through fault and fracture systems. Field relationships show that this fluid circulation started latest in middle Early Jurassic time, when fault activity migrated from the proximal to the future distal margin. We propose that it evolved chemically as a result of the involvement of the granitic basement forming the footwall of the extensional detachment system. Hydrothermal activity continued until the Middle/Late Jurassic, when tectonic activity shifted outwards leading to the exhumation of mantle rocks. This paper provides an original contribution to better understand the complex evolution of hyperextended continental rift domains and to constrain their thermal regimes.

VASCULARISED HOMOLOGOUS BONE GRAFT AND BONE MARROW NUCLEATED CELLS TRANSPLANTATION TO ENHANCE ANGIOGENESIS IN THE REPAIR OF CRITICAL SIZE BONE DEFECT: AN ANIMAL STUDY

Autologous bone grafting is a standard procedure for the clinical repair of skeletal defects, and good results have been obtained. Autologous vascularized bone grafting is currently the procedure of choice because of high osteogenic potential and resistance against reabsorption. Disadvantages of this procedure include limited availability of donor sites, clinical difficulty in handling, and a failure rate exceeding 10%. Allografts are often used for massive bone loss, but since only the marginal portion is newly vascularized after the implantation non healing fractures are often reported, along with a graft reabsorption. To overcome these problems, some studies in literature tried to conjugate bone graft and vascular supply, with encouraging results. On the other side, several studies in literature reported the ability of bone marrow derived cells to promote neo-vascularization. In fact, bone marrow contains not only hematopoietic stem cells (HSCs) and MSCs as a source for regenerating tissues but also accessory cells that support angiogenesis and vasculogenesis by producing several growth factors. In this scenario a new procedure was developed, consisting in an allogenic bone graft transplantation in a critical size defect in rabbit radius, plus a deviation at its inside of the median artery and vein with a supplement of autologous bone marrow concentrate on a collagen scaffold. Twenty-four New Zealand male white rabbits (2500–3000 g) were divided into 2 groups, each consisting of 12 animals. Surgeries were performed as follow: −Group 1 (#12): allogenic bone graft (left radius) / allogenic bone graft + vascular pedicle + autologous bone marrow concentrate (right radius) −Group 2 (#12): sham operated (left radius)/ allogenic bone graft + vascular pedicle (right radius) For each group, 3 experimental time: 8, 4 and 2 weeks (4 animals for each time). The bone used as graft was previously collected from an uncorrelated study. An in vitro evaluation of bone marrow concentrate was performed in all cases, and at the time of sacrifice histological and histomorphometrical assessment were performed with immunohistochemical assays for VEGF, CD31 e CD146 to highlight the presence of vessels and endothelial cells. Micro-CT Analysis with quantitative bone evaluation was performed in all cases. The bone marrow concentrate showed a marked capability to differentiate into osteogenic, chondrogenic and agipogenic lineages. No complications such as infection or intolerance to the procedure were reported. The bone grafts showed only a partial integration, mainly at the extremities in the group with vascular and bone marrow concentrate supplement, with a good and healthy residual bone. immunohistochemistry showed an interesting higher VEGF expression in the same group. Micro CT analysis showed a higher remodeling activities in the groups treated with vascular supplement, with an area of integration at the extremities increasing with the extension of the sacrifice time. The present study suggests that the vascular and marrow cells supplement may positively influence the neoangiogenesis and the neovascularization of the homologous bone graft. A longer time of follow up and improvement of the surgical technique are required to validate the procedure.

Transfer zones in an oblique back-arc basin setting: Insights from the Latium-Campania segmented margin (Tyrrhenian Sea)

New multichannel seismic reflection profiles were acquired to unravel the structure of a portion of the eastern margin of the Tyrrhenian basin. This extensional feature is part of an Oligocene to Present back-arc basin in the hangingwall of the west directed Apennines subduction system. The basin provides excellent conditions to investigate the early stage processes leading to the development of rifted passive margins and to the emplacement of oceanic crust in an oblique setting. The interpreted post-stack-migrated seismic profiles highlight the geometry and kinematics of the Pontine escarpment that connects the Latium-Campania continental margin to the Vavilov basin. The latter is the main feature of the area, related to the early Pliocene extension of the Tyrrhenian Sea. Several morphological variations are pointed out along strike, mirroring different structural settings of the margin itself: a steeper margin to the north corresponds to high-angle possibly transtensional faults, whereas a smooth slope in the southern portion corresponds to several more distributed listric faults. This work contributes to the understanding of the interplay between extensional and transtensional tectonics along the margins of an oblique back-arc basin.

Leiopathes glaberrima millennial forest from SW Sardinia as nursery ground for the small spotted catshark Scyliorhinus canicula

Abstract Association between habitat structuring organisms and other species has great relevance for ecosystem‐based conservation measures. Those occurring in temperate areas, particularly in the upper portion of the continental margin, are mostly unknown or not properly understood because of the difficulty to discriminate co‐occurrence and real functional linkages among species. Deep water coral assemblages over the Carloforte Shoal (south‐west Sardinia; 180–210 m depth) were investigated using ROV surveys. During the surveys, more than 740 egg‐capsules of the spotted catshark Scyliorhinus canicula, identified after hatching experiments in captivity, were found attached exclusively to colonies of the long‐living black coral Leiopathes glaberrima. Although based on a spot finding, the results show that coral forests are not only hotspots of biodiversity, but can also serve as nursery grounds for S. canicula. The protection of these millennial coral forests is therefore to be considered a priority.

Gently sloping shear zones in the Belomorian Mobile Belt: Geology, structure, and P–T parameters

The Belomorian Mobile Belt (BMB) in northern Karelia mostly consists of gently sloping shear zones, whose gneisses and migmatized amphibolites and blastomylonites are typically thinly banded, with their banding consistently dipping north- and northeastward. These gently sloping shear zones were not affected by folding after they were produced and are not cut by Paleoproterozoic metabasite dikes. Intrusive metabasites in the gently sloping shear zones make up relatively small (usually <5 m) equant or elongate bodies and occur as fragments of larger bodies. These fragments are often concentrated in stripes. Metabasites in the gently sloping shear zone are sometimes also found as lenses and tabular bodies of relatively small thickness, which are conformable with the foliation of the host rocks. The gently sloping shear zones cut across older domains of more complicated structure, which suggests that these zones are gently sloping ductile shear zones. Along these zones, the nappes were thrust south- and southwestward, and this process was the last in the origin of major structural features of BMB when the Paleoproterozoic Lapland–Kola orogen was formed. Practically identical age values were obtained for the gently sloping shear zone in the two widely separated Engonozero and Chupa segments of BMB: 1879 ± 21 Ma (40Ar/39Ar amphibole age of amphibolite whose protolith was mafic rock) and 1857 ± 13 Ma (Sm–Nd mineral isochron age of garnet amphibolites after gabbronorite). The P–T metamorphic parameters in these gently sloping shear zones are remarkably different from the metamorphic parameters outside these zones: the pressure is 3–4 kbar lower and the temperature is 60–100°C lower. Thrusting-related decompression triggered the transition from the older high-pressure episode of Paleoproterozoic metamorphism to a younger syn-thrusting higher temperature metamorphic episode. The peak metamorphic parameters corresponding to the boundary between the amphibolite and granulite facies were reached only in the central portions of the shear zones: T= 680–760°C, P = 8.0–11.9 kbar. In areas of the most intense migmatization, temperature estimates in the central portions of the shear are as high as 810–830°C. The marginal portions of the shear zones were formed at lower temperatures of 610–630°C. The temperature heterogeneous and rock heating in the gently sloping shear zones may have resulted from flows of high-temperature metamorphic fluid that were focused to the central portions of the zones.