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The Las Minas area corresponds to an exhumed geothermal system considered a proxy for the deep part of the nearby Los Humeros active geothermal system. The stratigraphic succession is made up of: Palaeozoic-Miocene granitoids, a thick Jurassic- Cretaceous carbonate succession, Neogene lava flows and volcano-sedimentary deposits. Linked to a Miocene magma intrusion, marble and skarn rock-volumes developed by contact metamorphism and geothermal fluid flow. Faults are arranged in SW- and NNW-striking systems. These controlled the morphological evolution and favored Neogene-Quaternary dyke emplacement. Faulting gave rise to a tectonic depression where lacustrine sediments and pyroclastics deposited. Skarn rocks are mainly located at fault intersections and along pre-existing discontinuities, suggesting the role of bedding and/or fractures in channeling deep fluids. Results give inputs for exploration at depth of Los Humeros geothermal system.

Background and Aims The lowlands of South America appear to be remarkably important in the evolutionary history of maize, due to new evidence that suggests that maize dispersed from Mexico and arrived in this region in a state of partial domestication. This study aimed to identify dispersal patterns of maize genetic diversity in this part of the continent. Methods A total of 170 maize accessions were characterized with 4398 single nucleotide polymorphisms (SNPs) and analysed to determine if maize dispersal was associated with types of endosperm and indigenous language families. Key Results Four genetic groups were identified in the discriminant analysis of principal components and five groups in the cluster analysis (neighbour-joining method). The groups were structured according to the predominance of endosperm types (popcorn, floury, flint/semi-flint). Spatial principal component analysis of genetic variation suggests different dispersal patterns for each endosperm type and can be associated with hypotheses of expansions of different indigenous groups. Conclusions From a possible origin in Southwestern Amazonia, different maize dispersal routes emerged: (1) towards Northern Amazonia, which continued towards the Caatinga and south-eastern Atlantic Forest (Floury); (2) towards Southern Brazil, passing through the Cerrado and Southern Atlantic Forest reaching the Pampa region (Floury); and (3) along the Atlantic Coast, following Tupi movements originating from two separate expansions: one (Tupinamba) from north to south, and the other (Guarani) in the opposite direction, from south to north (flint, floury and popcorn).

In our reply we demonstrate the inconsistency of the comment we received from Mazzarini et al. Our data, models and conclusions are solid and framed in the regional evolution of the Northern Apennines, typified by eastward migration of coeval extensional tectonics and magmatism since late Miocene. We show that understanding the natural processes recognizable in the Elba Island requires a scientific approach based on reproducible, reliable and high-quality datasets, independently of the scale of observation.

We review and refine the geological setting of an area located nearby the Tyrrhenian seacoast, in the inner zone of the Northern Apennines (southern Tuscany), where a Neogene monzogranite body (estimated in about 3 km long, 1.5 km wide, and 0.7 km thick) emplaced during early Pliocene. This magmatic intrusion, known as the Gavorrano pluton, is partially exposed in a ridge bounded by regional faults delimiting broad structural depressions. A widespread circulation of geothermal fluids accompanied the cooling of the magmatic body and gave rise to an extensive Fe-ore deposit (mainly pyrite) exploited during the past century. The tectonic setting which favoured the emplacement and exhumation of the Gavorrano pluton is strongly debated with fallouts on the comprehension of the Neogene evolution of this sector of the inner Northern Apennines. Data from a new fieldwork dataset, integrated with information from the mining activity, have been integrated to refine the geological setting of the whole crustal sector where the Gavorrano monzogranite was emplaced and exhumed. Our review, implemented by new palynological, petrological and structural data pointed out that: (i) the age of the Palaeozoic phyllite (hosting rocks) is middle-late Permian, thus resulting younger than previously described (i.e., pre-Carboniferous), (ii) the conditions at which the metamorphic aureole developed are estimated at a temperature of c. 660 °C and at a depth lower than c. 6 km, (iii) the tectonic evolution which determined the emplacement and exhumation of the monzogranite is constrained in a transfer zone, in the frame of the extensional tectonics affecting the area continuously since Miocene.

Exhumation and cooling of upper crustal plutons is generally assumed to develop in the brittle domain, thus determining an abrupt passage from crystallization to faulting. To challenge this general statement, we have applied an integrated approach involving meso- and micro-structural studies, thermochronology, geochronology and rheological modeling. We have analyzed the Miocene syn-tectonic Porto Azzurro pluton on Elba (Tuscan archipelago – Italy), emplaced in an extensional setting, and have realized that its fast exhumation is accompanied by localized ductile shear zones, developing along dykes and veins, later affected by brittle deformation. This is unequivocally highlighted by field studies and the analysis of microstructures with EBSD. In order to constrain the emplacement and exhumation rate of the Porto Azzurro pluton we performed U-Pb zircon dating and (U+Th)/He apatite thermochronology. It results in a magma emplacement age of 6.4 ± 0.4 Ma and an exhumation rate of 3.4 to 3.9 mm/yr. By thermo-rheological modeling we were able to establish that localized ductile deformation occurred at two different time steps: within felsic dykes when the pluton first entered into the brittle field at 380 kyr, and along quartz-rich hydrothermal veins at c. 550 kyr after pluton emplacement. Hence, the major conclusion of our data is that ductile deformation can affect a granitic intrusion even when it is entered into the brittle domain in a fast exhuming extensional regime.

The Pre-Mesozoic units exposed in the inner Northern Apennines mostly consist of middle-late Carboniferous-Permian successions unconformably deposited on a continental crust consolidated at the end of the Variscan (i.e. Hercynian) orogenic cycle (Silurian-Carboniferous). In the inner Northern Apennines, exposures of this continental crust, Cambrian?-early Carboniferous in age, have been described in the Northern Tuscany, Elba Island (Tuscan Archipelago) and, partly, in scattered and isolated outcrops of southern Tuscany. In this contribution, we reappraise the most significative succession (i.e. Risanguigno Formation) exposed in southern Tuscany and considered by most authors as part of the Variscan Basement. New stratigraphic and structural studies, coupled with palynological analyses, allow us to refine the age of the Risanguigno Fm and its geological setting and evolution. Based on the microfloristic content, the structural setting and the fieldwork study, we attribute this formation to late Tournaisian-Visean (middle Mississipian) time interval and conclude it is not showing evidence of a pre-Alpine deformation. These results, together with the already existing data, allow us to presume that no exposures of rocks involved in the Variscan orogenesis occur in southern Tuscany.

Comparison between fossil and analogue active geothermal systems permit to obtain key-parameters to define a conceptual model of the area under exploration. The approach is based on structural, kinematic, and fluid inclusions analyses. The fossil system is investigated to describe the distribution of the hydrothermal mineralization as witness of the fluid flow through geological structures and bodies, at depth. Structural and kinematic data (to define the preferential direction of fluid flow) are collected in structural stations and by scan lines and scan boxes on key outcrops. Distribution, length, width of fractures, and hydrothermal veins bring to evaluate permeability in the fossil system and, by analogy, in the deep roots of the active system. Fluid inclusions analysis shed light on density, viscosity, and temperature of the paleo-fluids. Data integration provides the hydraulic conductivity. In active geothermal systems, fieldwork is addressed to paleo-stress analysis with data from recent faults (

This study is part of the H2020-GEMex Project, a collaboration between Europe and Mexico for investigating super-hot geothermal systems. The novelty of this work is in its integrated methodological approach which bridges the past to the present and contributes to the reconstruction of conceptual models of deep geothermal systems, thus favoring appropriate strategies for deep exploration. The Las Minas mining area (Veracruz State) where Cu-Fe-Au ore-deposits have been historically exploited, is considered as an exhumed Neogene geothermal system analogous to the deeper part of the Los Humeros geothermal field (Puebla State). We used an integrated approach, which involved structural and kinematic, petrological, geochemical, geochronological and fluid inclusion analyses of the pre-volcanic Paleozoic-Cretaceous succession, intruded by Miocene-Pliocene granitoids and mafic dykes. Our emphasis was on the (paleo) fluid-rocks interaction and the related structural control. The results indicate that saline and hypersaline fluids (up to 70 wt. % NaCl equiv.) of magmatic derivation and aqueous-carbonic fluids issued during metamorphic or metasomatic reactions with T up to 600-650°C were channeled along and in the intersection between the NW- and NE-trending faults and their damage zones. The faults are characterized by strike-slip to oblique-slip/normal movements. Fluids were also stored in carbonate rock-volumes at the contact with the granitoids. The distribution of the ore-deposits and hydrothermal alteration related to the interaction of geothermal fluids and hosting rocks indicates the importance of conduits (such as fractures and faults) in the reservoirs. Hence, understanding the relationships between ore-deposits, hydrothermal alteration and structures can increase our knowledge of the present geothermal fluids' deep circulation in the Los Humeros geothermal field.

Banded Ca-carbonate veins in travertine deposits are efficient recorders of the compositional fluctuations of geothermal fluids flowing (or flowed) from deep reservoirs up to the surface, within fault zones. In this view, these veins represent key tools for decoding those factors that influenced the geochemical variations. We have analyzed veins developed in fractures channeling geothermal fluids forming travertine deposits. The studied veins cut a fossil travertine fissure ridge, near the Larderello geothermal area (Iano area, southern Tuscany) where geothermal fluid circulation is favored by NE-trending strike-to-oblique-slip faults and their intersections with NW-trending normal ones. U-Th dating indicates that fluid circulation occurred from (at least) 172 ka to 21 ka. In this time span, the geothermal fluid changed in composition, and the banded Ca-carbonate veins recorded these variations in terms of mineralogical and stable isotope composition and temperature ( T ) of deposition. We also documented for the first time the occurrence of Mn-rich black tree-shaped structures within the veins. Mineralogy coupled with stable and clumped isotope measurements allows the reconstruction of some features (i.e., crystal texture, temperature, and CO2 origin) and the inference of the processes (i.e., pH, T, and pCO2 variations) that have controlled the fluid evolution through time. Multiple-stage and one-stage deposition processes have played an important role in modifying the stable isotope composition of banded Ca-carbonate veins; temperature coupled with pCO2 also influenced their mineralogical composition. Interpreted in the context of the tectonic setting, the data show that the NW-trending faults have mainly controlled travertine deposition. Their intersection with NE-trending faults, interpreted as transfer faults, highlights the important role of transfer zones in channeling the geothermal fluids.

Estimating values of permeability (k), efficient porosity (P) and hydraulic conductivity (K) by analysing field outcrops as analogue of geothermal reservoirs, is a timely theme useful for predictions during geothermal exploration programs. In this paper we present a methodology providing k, P and K values, based on geometric analysis of quartz-tourmaline faults-vein arrays hosted in micaschist exposed in south-eastern Elba Island (Tuscan Archipelago, Italy), considered as the analogue of rock hosting the so-called “deep reservoir” in the Larderello geothermal field. The methodology is based on the integration among structural geology, fluid inclusions results and numerical analyses. Through a detailed structural mapping, scan lines and scan boxes analyses, we have reconstructed three superposed faulting events, developed in an extensional setting and framed in the Neogene evolution of inner Northern Apennines. Geometrical data of the fault-veins array were processed by reviewing the basic parallel-plate model equation for k evaluation. Fluid inclusion analyses provided those salinity and pressure-temperature values necessary for defining density and viscosity of the parent geothermal fluids. Then, permeability, density and viscosity were joined to get hydraulic conductivity (K). Permeability is estimated between 5 × 10 −13 and 5 × 10 −17 m 2 with variations among the different faults generation, while the hydraulic conductivity is encompassed between 1.31 × 10 −8 and 2.4 × 10 −13 m/s. The obtained permeability and hydraulic conductivity values are comparable with those from several geothermal areas, and in particular from the Larderello geothermal field. The main conclusion is that the proposed integrated approach provides a reliable methodology to obtain crucial values, normally obtained after drilling, for developing numerical flow models of geothermal fluid path in active geothermal systems by field and laboratory analyses of analogue, exhumed, geothermal systems.

In the Honalilar area (Denizli Basin, Turkey), the occurrence of banded Ca-carbonate veins and travertine deposits, represented by a dismantled fissure ridge-type depositional system, are the evidence of a middle-late Pleistocene exhumed, shallow, hydrothermal system. Their occurrence offers the best opportunity to: (i) reconstruct the fluid paths from the underground to the palaeo-surface, and (ii) analyse the role of fault zones in controlling the permeability and fluids circulation. Permeability developed in overstepping regional scale normal faults, with a slight left-lateral oblique-slip component. At the surface, faults favored the localization and development of a fissure ridge-type travertine deposit. At depth, the root of the hydrothermal system consists of W-E oriented fractures filled of up to 6.5 m thick Ca-carbonate veins, developed in a high dilatation zone. It corresponds to the step-over determined by the oblique-slip kinematics of the NW-striking main faults. The high dilatation step-over zone contrasted the progressive sealing induced by the concomitant Ca-carbonate deposition within the fractures, thus favoring permeability maintenance and fluids circulation for at least 200 ka. This evidence adds key inputs for predicting permeable volumes during geothermal exploration in areas affected by extensional tectonics. The main NW-oriented faults remained active even after the hydrothermal fluid flow, causing the dismantlement and progressive exhumation of the upper part of the hydrothermal system. © 2020 Elsevier Ltd

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Studies on hydrothermal fluids circulation and tectonic structures improve the geothermal exploration and ex- ploitation in Iceland. In this paper we present the results of an integrated study (structural, kinematic, fluid inclu- sions analyses) carried out on a fossil and exhumed geothermal system at Geitafell (SE Iceland), considered an analogue of the active Krafla geothermal system (NE Iceland). Our work is addressed to the relationships be- tween the main structures and the paleo-geothermal fluids circulation at the boundary between the magma chamber (with magma of gabbroic composition) and host rocks, with the aim to get information on those factors having controlled the hydrothermal fluids flow, its storage and the rocks-fluid interaction, at 1-2 km crustal depth. The structural study is mostly based on defining the architecture of mineralized brittle shear zones, where, by measuring length and width of mineralized fractures, permeability was computed in 1.3 × 10-14 m2. As regards the hydrothermal paleo-fluids, fluid inclusions in hydrothermal quartz and calcite, usually associated with epidote and chlorite (i.e., the typical alteration minerals found in Icelandic geothermal fields), re- corded a fluid circulation with temperature ranging from about 255 °C to 320 °C, and boiling at the highest tem- perature. Transient pressure drop, likely related to fracture opening and propagation during tectonic activity, triggered local boiling process testified by fluid inclusions in a calcite sample. During a late evolution the system progressively cooled down to 60-90 °C. Paleo-geothermal fluids were characterized by low-salinity meteoric water, although higher salinity fluids (up to 10.6 wt% NaCl equiv.) entered in the system and mixed with mete- oric fluid. In the end, based on results from fluid inclusions, derived fluid density, permeability values and model- ing of viscosity, hydraulic conductivity between 2.8 × 10-8 to 1.8 × 10-7 m/s, was also computed within the fluids-channelling brittle shear zones. We finally encourage the key-study of fossil geothermal systems as a tool for getting parameters commonly obtained after drilling in active systems.

Estimating values of permeability (k), efficient porosity (P) and hydraulic conductivity (K) by analysing field outcrops as analogue of geothermal reservoirs, is a timely theme useful for predictions during geothermal exploration programs. In this paper we present a methodology providing k, P and K values, based on geometric analysis of quartz-tourmaline faults-vein arrays hosted in micaschist exposed in south-eastern Elba Island (Tuscan Archipelago, Italy), considered as the analogue of rock hosting the so-called "deep reservoir" in the Larderello geothermal field. The methodology is based on the integration among structural geology, fluid inclusions results and numerical analyses. Through a detailed structural mapping, scan lines and scan boxes analyses, we have reconstructed three superposed faulting events, developed in an extensional setting and framed in the Neogene evolution of inner Northern Apennines. Geometrical data of the fault-veins array were processed by reviewing the basic parallel-plate model equation for k evaluation. Fluid inclusion analyses provided those salinity and pressure-temperature values necessary for defining density and viscosity of the parent geothermal fluids. Then, permeability, density and viscosity were joined to get hydraulic conductivity (K). Permeability is estimated between 5 × 10-13 and 5 × 10-17 m2 with variations among the different faults generation, while the hydraulic conductivity is encompassed between 1.31 × 10-8 and 2.4 × 10-13 m/s. The obtained permeability and hydraulic conductivity values are comparable with those from several geothermal areas, and in particular from the Larderello geothermal field. The main conclusion is that the proposed integrated approach provides a reliable methodology to obtain crucial values, normally obtained after drilling, for developing numerical flow models of geothermal fluid path in active geothermal systems by field and laboratory analyses of analogue, exhumed, geothermal systems.

Background: Postmarketing surveillance studies (PMS) are an important tool for evaluating a drug’s effectiveness and safety in clinical practice. To our knowledge, no PMS on memantine monotherapy for moderately-severe-to-severe Alzheimer’s disease (AD) according to National Institute of Neurological and Communicative Disorders and Stroke — Alzheimer’s Disease and Related Disorders Association criteria has been conducted to date. Objective: The Lombardy Health Office, Italy, promoted this PMS to evaluate the effectiveness and safety of memantine in the treatment of moderately-severe-to-severe AD in clinical practice. Methods: A total of 451 patients with moderately-severe-to-severe AD (mean age 77 ± 7 years; 72% female), free of cholinergic medication, received memantine (standard titration to 10 mg twice daily). After 6 months of therapy, treatment effectiveness was evaluated according to two definitions of response (‘no deterioration’ and ‘improvement’), as measured by changes in baseline scores on the Clinical Global Impression of Change, Mini-Mental State Examination, Neuropsychiatric Inventory and Activities of Daily Living scales. The safety measure was the frequency of adverse events (AEs). Results: At 6-month assessment, 26.8% of subjects showed no deterioration and 3.8% showed improvement. In those showing no deterioration, response to treatment at the 3-month assessment was associated with a greater probability of a response at 6 months (adjusted odds ratio = 8.54; 95% CI 4.54, 16.05). Seventy patients (15.5%) experienced at least one AE and 39 (8.6%) discontinued treatment prematurely because of an AE. Of those who experienced an AE, 27 (38.6%) manifested behavioural and psychological symptoms of dementia. Conclusion: The proportion of responders to memantine treatment in this PMS was similar to that reported in a previous randomized clinical trial (26.8% vs 29%, respectively). The proportion of patients who discontinued treatment prematurely because of an AE (8.6%) was similar to that reported in two previous randomized clinical trials (10% and 12.4%). This PMS provides additional evidence that both the effectiveness and the tolerability of memantine may be transferred into real world medicine, where AD patients receiving treatment are not selected according to strict criteria.

Microsatellite primers were developed and optimized for patchouli (Pogostemon cablin) to characterize the patchouli Active Germplasm Bank of Universidade Federal de Sergipe. Creation of a genomic library for patchouli enabled the design of 12 microsatellite primers. Six of these microsatellites were polymorphic, revealing two well-defined groups of individuals that possess exclusive alleles. The data allowed us to characterize the patchouli active Germplasm Bank, identify its genetic diversity, and provide new information for researching this species.

The aim of this study is to evaluate memantine effectiveness on behavioural and psychological symptoms of dementia (BPSD) in clinical practice and to identify variables that may predict the therapy effects. The effects of memantine on behaviour were analysed in the database of a post-marketing surveillance study promoted by the Lombardy Region Health Office and involving 43 Alzheimer's disease (AD) Units. From July to December 2005, 399 moderately severe-to-severe AD patients free of cholinergic medications were enrolled, treated with memantine and followed-up for 6 months. BPSD were assessed in a subgroup of 297 patients [mean age 77 ± 8 years; 73% females; mean neuropsychiatric inventory (NPI) score 28 ± 24] for whom the 12-item NPI subscores at baseline, and at 3 and 6 months were available. The 12 BPSD were clustered as follows: affect, physical behaviour, psychosis and hypomania. The main outcome measure was the proportion of individual cluster responders at 6 months of therapy. The proportion of individual cluster responders was 30% affect, 24% physical behaviour, 29% psychosis, 27% hypomania. Patients taking 20 mg memantine daily during the study period had a statistically significant higher probability to experience behavioural improvement than those who discontinued treatment or did not complete memantine titration (affect OR 9.0; 95% CI 3.8-21.6; physical behaviour OR 17.8; 95% CI 5.9-53.6; psychosis OR 23.6; 95% CI 5.1-110.8). The logistic regression analysis was not applicable to the hypomania subsyndrome because of the low cluster prevalence. The standard 20 mg daily memantine treatment regimen was found to be associated with a modest 6-month behavioural improvement in the affect, physical behaviour and psychosis domains in 24-30% of patients.

The Guineagrass (Panicum maximum Jacq.) is one of the most important tropical forage grasses, but genetic knowledge and tools regarding this species are still limited. Therefore, 20 novel polymorphic microsatellite markers were developed, validated, and employed in estimating genetic relationships among 25 P. maximum genotypes selected from a Brazilian germplasm collection. In addition, they were tested for cross-species amplification in four other forage grass species. The number of alleles observed for each locus ranged from 4 to 12 (average 6.7). The values of polymorphism information content (PIC) varied from 0.41 to 0.83 (average 0.61) and the discriminating power (D) ranged from 0.53 to 0.98 (average 0.72). Cross-amplification demonstrated the potential transferability of these microsatellites to four tropical forage grass species. Cluster analysis based on the unweighted pair group method revealed three distinct groups: two clusters consisted of P. maximum genotypes and a third cluster, consisted of the other tropical forage grass species. The data demonstrated that the microsatellites developed herein have potential for germplasm characterization and genetic diversity analysis in P. maximum and other forage grass species.

In this study we investigated the genetic diversity of 10 populations of Brazilian Tall coconut trees, employing 13 SSR loci to characterize their genetic variability, population structure, and reproductive system. Made available in DSpace on 2011-04-09T14:45:23Z (GMT). No. of bitstreams: 1 20093561.pdf: 128802 bytes, checksum: 63bebad9c6c14b48f753c0213bfa4e76 (MD5) Previous issue date: 2011-01-26