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Earthquakes and related coseismic effects at the surface, such as liquefaction and lateral spreading, can impact humans due to the resulting economic or social disruptions (e.g. slope and foundation failures, flotation of buried structures, etc.). In this respect, the 2020 Petrinja Mw6.4 earthquake (Croatia) provided many examples of liquefaction and lateral spreading, as identified by the post-earthquake field reconnaissance campaigns. The observed liquefaction cases occurred in the alluvial plains of the Kupa, Sava and Glina Rivers or along faults, with ejecta composed of sands and/or gravels of different grain size and mineralogy. The lateral spreading phenomena were observed along river embankments and roads. In this context interest in studying these different features arose, and an international research team from Italy, the United States and Croatia recently performed an intensive geological, geotechnical and geophysical campaign to assess the liquefaction susceptibility at selected sites located throughout the epicentral area (from Glina to Petrinja to Sisak). Innovative in-situ test equipment, such as the dynamic cone penetration test (DPT) for liquefied gravels and the Medusa flat dilatometer test (Medusa DMT) for liquefied sands, were employed in combination with standard in-situ tests,such as the standard penetration test (SPT), the piezocone test (CPTU), and shear wave velocity (Vs) measurements. These techniques were employed to verify their advantages relative to the existing iquefaction triggering charts and to characterize the soil properties of the buried liquefied layers and the non-liquefied crust. This paper presents preliminary results and comparisons at some of the investigated liquefaction sites.

Background: Biotechnological breeding of elite sugarcane cultivars is currently limited because of the difficulty of regenerating plants by tissue culture. Here, we report that commercially elite sugarcane genotypes, which are adapted to Argentinian agro-ecological conditions, are capable of being regenerated via indirect somatic embryogenesis. Leaf rolls of five elite genotypes were cultured following two callus induction protocols using different concentrations of 2,4-D as the growth regulator. Embryogenic calluses were regenerated under light conditions. Regenerated plants were subsequently acclimatized in the greenhouse under two acclimatization procedures before being transplanted to the field. Results: Four of the five genotypes were able to form somatic embryos following the two induction protocols. The variables related to embryogenic callus production were influenced by the interaction between genotype and culture conditions. For plant regeneration, the embryogenic calluses were further cultured on an IBA-supplemented medium, where we observed a high genotype dependence. Calluses from the four cultivars regenerated a good number of plants. With the procedures described here, we obtained more than 90% of well-acclimatized plants both in the greenhouse and in the field. Conclusions: This protocol provides a simple way to regenerate sugarcane plants through indirect somatic embryogenesis. Also, the results confirm that tissue culture ability is highly genotype-dependent in sugarcane. Our findings suggest that these elite cultivars could be good candidates for biotechnological breeding. EEA Famaillá Fil: Di Pauli, Valentina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famaillá; Argentina Fil: Fontana, Paola Daniela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famaillá; Argentina Fil: Lewi, Dalia Marcela. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Genética; Argentina Fil: Felipe, Arturo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famaillá; Argentina Fil: Erazzú, Luis E. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famaillá; Argentina.

We provide new evidence of the preservation of 34S-enriched signals in methane seep-impacted sediments from two onshore Miocene outcrops located in the northern Apennines (Italy). Selected outcrops include methane-derived authigenic carbonates (MDAC) with δ13C composition between − 42.3 and − 18.2‰. MDACs contain chemosynthetic clams and abundant pyrite indicative of formation close to or within a shallow sulfate-methane transition zone (SMTZ). This study aims to evaluate the relative contributions of background organic matter mineralization and anaerobic oxidation of methane (AOM) to sulfate consumption and to gain insight into the transport process (i.e., diffusion, advection) controlling the depth of the SMTZ. Host sediments were investigated by CHN elemental analysis coupled with total sulfur (TS) and sulfur isotopic measurements on bulk samples. Total organic carbon (TOC) measurements reveal a consistent and low amount of organic carbon (TOC 0‰ and up to + 17.1‰), which is characteristic of sulfides precipitated in association with AOM. We propose that advection of methane-rich fluids was responsible for maintaining the shallow depth of the studied paleo-SMTZs. AOM at paleo-SMTZ positions in the investigated seep-impacted sediments resulted in excess bicarbonate and sulfide production, favoring solid-phase MDAC and iron sulfide precipitation.

The 87Sr/86Sr, REE and Mo U systematics were investigated in Miocene seep carbonates formed on accretionary ridges at the front of the northern Apennine wedge. Here we evaluate fluid sources, seepage intensity and redox conditions during carbonate precipitation. Micrite matrix and early calcite cements lining cavities are the main authigenic carbonate phases and show negligible diagenetic alteration. Their AOM-related (anaerobic oxidation of methane) origin is evident from δ13C values ranging from −38.7‰ to −25.7‰. The 87Sr/86Sr ratios in carbonates vary between 0.708659 and 0.709132. Most micrite values fall within the range of Middle Miocene seawater (Langhian, MNN5a biozone), in agreement with the biostratigraphy of the host sediments, thus reflecting precipitation of seep carbonates close to the seafloor. Highly radiogenic 87Sr/86Sr ratios, of early calcite cements and micrite from conduit-rich facies at the base of carbonate bodies, likely derived from the interaction of fluids with detrital clays during the fault-controlled upward migration through the underlying terrigenous turbidite successions. Strong Mo and U enrichments in carbonates, with MoEF and UEF up to 233.5 and 86.6 respectively, coupled with (Mo/U)EF ratios ranging between 0.7 and 9.7, indicate dynamic redox conditions, episodically sulfidic and restricted to porewaters. This interpretation is also supported by enrichments in MREE of micrites and a general absence of negative Ce anomalies. These new data provide an indirect indication of rates and temporal variability of AOM at fossil methane seeps developed on a thrust related anticline and help to constrain the complex interaction between fluid migration pathways, seepage intensity and environmental conditions as observed in modern seep analogues.

We present new field data from three outcrops of Miocene methane-derived authigenic carbonates in the foredeep of the northern Apennines that contain chemosynthetic fauna and record a long history (∼1 Ma) of shallow fluid seepage linked to seafloor anaerobic oxidation of methane. The studied outcrops show similar features in terms of carbonate morphology, facies, spatial distribution and lateral and vertical contacts with the enclosing sediments. Methane-derived carbonates occur in two structural positions: 1) on the slope of the accretionary wedge in hemipelagites draping buried thrust-related anticlines, and 2) at the leading edge of the deformation front in the inner foredeep, within fault-related anticlines standing above the adjacent deep seafloor as intrabasinal ridges. We compare fossil seeps with two extensively investigated modern analogues: the Hikurangi Margin, offshore New Zealand and Hydrate Ridge, on the Cascadia margin, offshore the U.S.A. These analogues share a similar compressive structural setting and are marked by the presence of variably extensive and voluminous methane-derived carbonate bodies and chemosynthetic fauna on the present-day seafloor. The comparison allows us to propose a model for the evolution of fluid seeps on thrust-related ridges. At the deformation front, uplift and geometry of the anticlinal ridges are controlled by the growth of splay faults, mostly blind, connected to the basal detachment, favoring the migration of fluids toward the incipient anticline. Fold development generates extensional stresses in the hinge zone of the anticline, promoting the development of normal faults; fluid migration pathways and seafloor seeps shift from the forelimb toward the crest of the ridge as the structures evolve. In the slope setting, far from the deformation front, thrust faults and extensional faults in buried anticlines remain the main fluid migration pathways to sustain seepage at the seafloor. After reaching a mature stage within the wedge, the structure is less active and buried in the slope environment of the evolved prism.

The effects of global warming on marine gas hydrate stability along continental margins is still unclear and discussed within the scientific community. Long-term datasets can be obtained from the geological record and might help us better understand how gas-hydrate reservoirs responds to climate changes. Present-day gas hydrates are frequently associated or interlayered with authigenic carbonates, called clathrites, which have been sampled from many continental margins worldwide. These carbonates show peculiar structures, such as vacuolar or vuggy-like fabrics, and are marked by light δ13C and heavy δ18O isotopic values. Evidences of paleo-gas hydrate occurrence are recorded in paleo-clathrites hosted in Miocene deposits of the Apennine chain, Italy, and formed in different positions of the paleo foreland system: in wedge-top basins, along the outer slope of the accretionary prism, and at the leading edge of the deformational front. The accurate nannofossil biostratigraphy of sediment hosting paleo-clathrites in the northern Apennines allowed us to ascribe them to different Miocene nannofossil zones, concentrated in three main intervals: in the Langhian (MNN5a), in the upper Serravallian-lower Tortonian (MNN6b-MNN7) and the upper Tortonian-lowermost Messinian (MNN10-MNN11). By comparing paleo-clathrite distributions with 3rd order eustatic curves, they seem to match phases of sea-level lowering associated with cold periods. Therefore, we suggest that the drop in the hydraulic pressure on the plumbing system during sea-level lowering shifted the bottom of the gas hydrate stability zone to shallower depths, inducing paleo gas-hydrate destabilization. The uplift of the different sectors of the wedge-top foredeep system during tectonic migration might have amplified the effect of the concomitant eustatic sea-level drop, reducing the hydrostatic load on the seafloor and triggering gas-hydrate decomposition. We suggest that Miocene climate-induced sea-level changes played a role in controlling gas hydrate stability and methane emissions along the northern Apennine paleo-wedge, with hydrate destabilization roughly matching with sea-level drops and cooling events.

The Marnoso-arenacea turbidite succession outcropping in northern Italy is one of the most studied deep-water systems worldwide due to its excellent exposure. Despite the well-established sedimentology of the arenaceous succession, the origin of fine-grained intervals within the Marnoso-arenacea Fm is reconsidered in the light of methane-rich fluid expulsion, in particular as seep-carbonates are present. Fine-grained intervals are marked by limited vertical and lateral extent, in the order of 102 m and 103 m respectively, and are often associated with small-scale sediment deformation. In this study, we conduct a detailed sedimentological and stratigraphic investigation of the well-exposed Prati Piani fine-grained interval (Serravallian in age) with particular focus on the characterization of trace fossils and seep-carbonates. Trace fossils interpreted as Thalassinoides are widespread throughout the interval and form a complex network testifying long-lasting burrowing activity of decapod crustaceans. Seep-carbonates crop out at different stratigraphic levels and form meter-sized blocks with δ13C from −33.2‰ to −18.2‰. The occurrence of aragonite cements and fossil chemosymbiotic fauna indicates episodic carbonate precipitation close to the paleo-seafloor. Although crustaceans have been frequently reported grazing microbial mats at modern seeps and leaving a 13C-depleted isotopic signature in trace fossils, in our study we found only one slightly depleted δ13C value (−9.5‰,) allowing us to exclude preferential authigenesis. Moreover, burrows are filled by detrital fine-grained sediments and hemipelagic micrite that may have diluted the methane-related signature. The association between in situ seep-carbonates and well-preserved trace fossils is of use to interpret the interval as formed by fine-grained sedimentation draping a thrust-related anticline. In this model, the stratigraphically- and laterally-confined deformed zones affecting the Prati Piani interval reflect in-situ soft-sediment deformation and small-scale slumping induced by fluid seepage along the ridge, consistent with present-day observations from several continental margins worldwide.

The evolution of the San Marino carbonate succession, developed on a wedge-top basin of the northern Apennines during the Middle Miocene (Torriana outcrop, Marecchia Valley), was studied through a high-resolution stable isotope analysis on different carbonate components. A marked positive carbon isotopic excursion is identified at ca. 16 Ma. The excellent correlation of the San Marino δ13C carbonates with the global δ13C reference curve from Zachos et al. (2008) allows to link the marked positive δ13C present in the San Marino section with the global carbon isotope maximum of the Monterey event. Subordinate long-eccentricity-driven δ13C cycles (~405 kyr) as recorded by Holbourn et al. (2007) were also identified. The correlation with carbon signatures of coeval successions of the Mediterranean region shows that this main carbon isotopic excursion at the Burdigalian–Langhian boundary is widely recorded and predates the crisis of these heterozoan shelves. The demise of the San Marino shelf resulted from a combination of global and regional factors that controlled the nutrient budget, the detrital input and the subsidence of the basin. The high-resolution chemostratigraphy of San Marino succession shows that even though the shelf evolved in the complex setting of a wedge-top basin, which should be largely influenced by local factors (i.e. tectonic subsidence and detrital input), it records the Monterey event and its eccentricity paced rhythms with high precision. This highlights the strong connection of the Monterey event with the development and subsequent demise of shallow water carbonate depositional systems in the Mediterranean, irrespective of variable and changing local conditions.

This paper shows and compares the experimental results obtained by using a standard cone (10 cm2) and a mini piezocone (2 cm2). Tests were carried out at Calendasco (Piacenza, Italy) in a...

In the engineering geology field increased attention has been posed in recent years to potential liquefaction mitigation interventions in susceptible sand formations. In silty sands this is a major challenge because, as the fines content increases, vibratory methods for densification become progressively less effective. An alternative mitigation technique can be the installation of Rammed Aggregate Pier® (RAP) columns that can increase the resistance of the soil, accounting for its lateral stress increase and for the stiffness increase from soil and RAP composite response. To investigate the influence of these factors on liquefaction resistance, full-scale blast tests were performed at a silty sand site in Bondeno (Ferrara, Italy) where liquefaction was observed after the 2012 Emilia-Romagna earthquake. A multidisciplinary team of forty researchers carried out devoted experimental activities aimed at better understanding the liquefaction process at the field scale and the effectiveness of the treatment using inter-related methods. Both natural and improved areas were investigated by in-situ tests and later subjected to controlled blasting. The blast tests were monitored with geotechnical and geophysical instrumentation, topographical surveying and geological analyses on the sand boils. Results showed the RAP effectiveness due to the improvement of soil properties within the liquefiable layer and a consequent reduction of the blast-induced liquefaction settlements, likely due to soil densification and increased lateral stress. The applied multidisciplinary approach adopted for the study allowed better understanding of the mechanism involved in the liquefaction mitigation intervention and provided a better overall evaluation of mitigation effectiveness.

Em vista da dificuldade encontrada atualmente em tornar as aulas e conteúdos trabalhados mais atrativos e significativos para os estudantes, o presente trabalho pretende desenvolver um projeto para construção de um aquecedor solar utilizando a pedagogia de projetos. Prado (2001) enaltece em seu artigo a importância da pedagogia de projetos, no que diz respeito a identificar as estratégias envolvidas para desenvolver no aluno competências e habilidades. Essas estratégias são diferentes maneiras de se abordar um conteúdo, que podem ser: aulas expositivas, exposição de vídeos, realização de experimentos e criação de mapas conceituais. A aprendizagem significativa de David Ausubel é o embasamento para a aplicação deste produto, direcionado para turmas de 9º ano do ensino fundamental. Para Ausubel, o que mais influencia o processo de ensino-aprendizagem é o que o educando já sabe (MOREIRA, M. A; OSTERMANN, F, 1999), desse modo, identificando os conhecimentos prévios, subsunçores, dos estudantes e preparando as aulas baseadas nessa informação, o estudante será capaz de ancorar novos conhecimentos nesses subsunçores. Nesse contexto, a pedagogia de projetos envolve três aspectos a se considerar: primeiro, os objetivos, as intenções e ações devem ser claras, que neste caso é o aprendizado de termologia através de aulas variadas; segundo, é preciso incorporar novas tecnologias para enriquecer e agregar avanços e, terceiro, são os conceitos das áreas de conhecimentos relacionados com a problemática em estudo (PRADO, 2001). Vale ressaltar que é de suma importância o preparo do professor em lidar com esta prática pedagógica, senão a ação é em vão. A experimentação é uma estratégia capaz de aproximar o conteúdo à prática, propicia a participação ativa do estudante, fazendo com que se sintam desafiados ao construir um experimento (BRASIL, 1997). Além disso, interagem e trocam experiências e, nesse processo de elaboração de estratégias para resolver os desafios, o próprio estudante constrói seu conhecimento. Desse modo, a pedagogia de projetos estimula o estudante a pesquisar para responder seus questionamentos, proporcionando uma competição sadia na construção, neste caso, de um aquecedor mais eficiente e barato. Em vista disso, organizar e trabalhar os conteúdos em forma de projetos promove a utilização de diferentes ferramentas, além de esta representar uma metodologia que pode despertar o interesse dos estudantes, tornando-os mais participativos e, em consequência, o processo de ensino-aprendizagem pode se tornar mais atrativo e eficiente. Logo, com a aplicação da metodologia supracitada, os estudantes terão a oportunidade de participar mais ativamente da construção do conhecimento. A interação promovida pela realização de experimentos e pelo trabalho em grupo, por meio de projetos, oportuniza uma troca entre estudantes de diferentes níveis, bem como promove o professor ao patamar de mediador das situações de ensino-aprendizagem. As reflexões oportunizadas após cada momento vivenciado nas aulas e mediadas pelo professor constituirão em embasamento para a construção do conhecimento individual e coletivo. Dessa forma, o trabalho pretende despertar nos estudantes interesse nos conteúdos de termologia, incentivando, desse modo, a autonomia em pesquisar e descobrir e, ainda, melhorar o nível de instrução também de professores, fornecendo a estes subsídios para que o processo de ensino-aprendizagem ocorra satisfatoriamente dentro do conteúdo proposto.

Paleoenvironmental and paleoclimatic variations experienced by the Mediterranean region during the Miocene Burdigalian-Langhian interval have been investigated through analysis of biomarker signals (n-alkanes and glycerol dialkyl glycerol tetraethers, GDGTs) from slope mudstones of the northern Apennines (Marne di Vicchio Fm). Terrestrial signatures in marine sediments reflected by preserved long-chain n-alkanes with a identifiable odd-over-even carbon number predominance attest to the thermal immaturity of the sedimentary rock. Abundances of n-C27, n-C29 and n-C31 alkanes, coupled with the carbon isotopic signatures of the n-C31 homologue suggest that Mediterranean vegetation crossed a transition phase adapting to arid conditions that may favored a shift from woodland to wooded grassland during the Middle Miocene. This ecosystem evolution could have been favored by the passage from warm humid conditions to a warm drier climate, as indicated by GDGT-based TEX86 and BIT indexes. Strong similarities between these Mediterranean biomarker records and those from the Atlantic (DSDP Sites 94, 516, 608) imply a constant connection of the western Mediterranean to the Atlantic Ocean from ~19 Ma to ~14.5 Ma.

Lithium Ion Batteries (LIB) find not only wide use in portable devices and consumer electronics, but also attract increasing attention in stationary energy storage and the automotive sector. In this regard, LIBs play a significant role as intermediate energy storage due to their high volumetric and gravimetric energy, high power density, and long cycle life. To achieve the required performance, the interaction of novel anode and cathode materials is of paramount interest. Particularly, the safety of cell operation must be assessed with respect to the formation of volatile and reactive species during cycling which can negatively alter cell components. Gas chromatography mass spectroscopy (GCMS) has proven to be a reliable tool for species detection. Unfortunately, conventional GC systems lack time resolution for in-situ gas analysis regarding fast processes, for example battery failure. Therefore, developing operando testing methods with improved time resolution is key to giving insight into electrolyte alterations during battery operation. Here one of them, a novel multiplex injection method is presented as a monitoring technique for gas species arising from the decomposition of conventional LIB electrolytes. The combination of the multiplexing technique and GCMS allows the analysis of fast decomposition processes by 15 fold increase of time resolution compared to conventional gas chromatography. In addition, FTIR allows online monitoring of selected vibration bands. Commercially produced pouch cells were monitored with respect to evolving gas species during battery operation under overcharge conditions. For the decomposition of LiPF6 / organic carbonate- based electrolytes alkanes, alcohols, ethers, esters, aldehydes and also derivatives that appear in the presence of hydrofluoric acid such as fluorinated alkane species, have been evaluated. The author gratefully acknowledges the FFG (Austrian Research Promotion Agency) for funding this research within project No. 858298.

Tubular carbonate conduits (TCC) represent the termination of fluid plumbing systems in environments of hydrocarbon seepage and play a relevant role in the discharge of methane from sub-seafloor sediments to the water column. However, the biogeochemical reactions and biological activities involved in their formation are not fully understood. To address this, TCC samples were collected with a remotely operated vehicle from the seabed on the SW flank of the Athina mud volcano in the eastern Mediterranean Sea. Petrographic, mineralogical, stable carbon and oxygen isotope and lipid biomarker analyses were performed to elucidate the formation processes of the tubular carbonates. Clotted and fibrous aragonite form the internal lining of the cavities, while the outer portion of the tubes is formed by micritic Mg-calcite cementing hemipelagic sediment. 13C-depleted Mg-calcite and aragonite (as low as −14.4‰ V-PDB) and lipid biomarkers (archaeol, −89.8‰ V-PDB) indicate that carbonate precipitation was influenced by sulfate-dependent anaerobic oxidation of methane (AOM). AOM locally enhances aragonite precipitation, thereby facilitating early lithification of the conduits within the mud volcano sediments. The size and morphology of the TCC comparable with the buried portion of tubeworm colonies found in the proximity of the sampling site. However, our results suggest that TCC likely formed by the action of burrowing organism rather than being mineralizations of the tubeworm colonies. This study provides new insights into the interpretation and understanding of TCC, highlighting the role of macrofaunal activity in the formation of migration pathways for hydrocarbon-rich fluids on the flank of a mud volcano.

The occurrence of seep-carbonates associated with shallow gas hydrates is increasingly documented in modern continental margins but in fossil sediments the recognition of gas hydrates is still challenging for the lack of unequivocal proxies. Here, we combined multiple field and geochemical indicators for paleo-gas hydrate occurrence based on present-day analogues to investigate fossil seeps located in the northern Apennines. We recognized clathrite-like structures such as thin-layered, spongy and vuggy textures and microbreccias. Non-gravitational cementation fabrics and pinch-out terminations in cavities within the seep-carbonate deposits are ascribed to irregularly oriented dissociation of gas hydrates. Additional evidences for paleo-gas hydrates are provided by the large dimensions of seep-carbonate masses and by the association with sedimentary instability in the host sediments. We report heavy oxygen isotopic values in the examined seep-carbonates up to +6&permil, that are indicative of a contribution of isotopically heavier fluids released by gas hydrate decomposition. The calculation of the stability field of methane hydrates for the northern Apennine wedge-foredeep system during the Miocene indicated the potential occurrence of shallow gas hydrates in the upper few tens of meters of sedimentary column.

Acidovorax spp. cause a wide range of economically important diseases in monocotyledonous and dicotyledonous plants, including sugarcane, corn, rice, oat, millet, foxtail watermelon, and orchid. In Argentina, the red stripe disease of sugarcane caused by Acidovorax avenae affects 30% of the milling stems with important economic losses. To explore the genetic diversity of this bacterium associated with red stripe in Argentina, multilocus sequence typing (MLST) was applied. This study included 15 local strains isolated from four different sugarcane planting regions and selected after random amplified polymorphic DNA analysis and reference strains of A. citrulli, A. avenae, and A. oryzae to investigate their phylogenetic relationships. MLST analysis resulted in five sequence types among the sugarcane A. avenae strains which constitute a clonal complex, meaning a common and close origin. Sugarcane strains were related to A. avenae from other hosts and distant to A. citrulli. Signals of frequent recombination in several lineages of A. avenae was detected and we observed that A. oryzae is closely related to A. avenae strains. This study provides valuable data in the field of epidemiological and evolutionary investigations of novel clone of A. avenae strains causing sugarcane red stripe. The knowledge of the genetic diversity and strain-host specificity are important to select the genotypes with the best response to the red stripe disease. Fil: Fontana, Paola. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina Fil: Tomasini, Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Patología Experimental. Universidad Nacional de Salta. Facultad de Ciencias de la Salud. Instituto de Patología Experimental; Argentina Fil: Fontana, Cecilia Alejandra. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina Fil: Di Pauli, Valentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina Fil: Cocconcelli, Pier Sandro. Università Cattolica del Sacro Cuore; Italia Fil: Vignolo, Graciela Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina Fil: Salazar, Sergio Miguel. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina

The effect of charging and discharging lithium iron phosphate-graphite cells at different temperatures on their degradation is evaluated systematically. The degradation of the cells is assessed by using 10 charging and discharging temperature permutations ranging from -20 °C to 30 °C. This allows an analysis of the effect of charge and discharge temperatures on aging, and their associations. A total of 100 charge/discharge cycles were carried out. Every 25 cycles a reference cycle was performed to assess the reversible and irreversible capacity degradation. A multi-factor analysis of variance was used, and the experimental results were fitted showing: i) a quadratic relationship between the rate of degradation and the temperature of charge, ii) a linear relationship with the temperature of discharge, and iii) a correlation between the temperature of charge and discharge. It was found that the temperature combination for charging at +30 °C and discharging at -5 °C led to the highest rate of degradation. On the other hand, the cycling in a temperature range from -20 °C to 15 °C (with various combinations of temperatures of charge and discharge), led to a much lower degradation. Additionally, when the temperature of charge is 15 °C, it was found that the degradation rate is nondependent on the temperature of discharge.

Em vista da dificuldade encontrada atualmente em tornar as aulas e conteúdos trabalhados mais atrativos e significativos para os estudantes, o presente trabalho pretende desenvolver um projeto para construção de um aquecedor solar utilizando a pedagogia de projetos. Prado (2001) enaltece em seu artigo a importância da pedagogia de projetos, no que diz respeito a identificar as estratégias envolvidas para desenvolver no aluno competências e habilidades. Essas estratégias são diferentes maneiras de se abordar um conteúdo, que podem ser: aulas expositivas, exposição de vídeos, realização de experimentos e criação de mapas conceituais. A aprendizagem significativa de David Ausubel é o embasamento para a aplicação deste produto, direcionado para turmas de 9º ano do ensino fundamental. Para Ausubel, o que mais influencia o processo de ensino-aprendizagem é o que o educando já sabe (MOREIRA, M. A; OSTERMANN, F, 1999), desse modo, identificando os conhecimentos prévios, subsunçores, dos estudantes e preparando as aulas baseadas nessa informação, o estudante será capaz de ancorar novos conhecimentos nesses subsunçores. Nesse contexto, a pedagogia de projetos envolve três aspectos a se considerar: primeiro, os objetivos, as intenções e ações devem ser claras, que neste caso é o aprendizado de termologia através de aulas variadas; segundo, é preciso incorporar novas tecnologias para enriquecer e agregar avanços e, terceiro, são os conceitos das áreas de conhecimentos relacionados com a problemática em estudo (PRADO, 2001). Vale ressaltar que é de suma importância o preparo do professor em lidar com esta prática pedagógica, senão a ação é em vão. A experimentação é uma estratégia capaz de aproximar o conteúdo à prática, propicia a participação ativa do estudante, fazendo com que se sintam desafiados ao construir um experimento (BRASIL, 1997). Além disso, interagem e trocam experiências e, nesse processo de elaboração de estratégias para resolver os desafios, o próprio estudante constrói seu conhecimento. Desse modo, a pedagogia de projetos estimula o estudante a pesquisar para responder seus questionamentos, proporcionando uma competição sadia na construção, neste caso, de um aquecedor mais eficiente e barato. Em vista disso, organizar e trabalhar os conteúdos em forma de projetos promove a utilização de diferentes ferramentas, além de esta representar uma metodologia que pode despertar o interesse dos estudantes, tornando-os mais participativos e, em consequência, o processo de ensino-aprendizagem pode se tornar mais atrativo e eficiente. Logo, com a aplicação da metodologia supracitada, os estudantes terão a oportunidade de participar mais ativamente da construção do conhecimento. A interação promovida pela realização de experimentos e pelo trabalho em grupo, por meio de projetos, oportuniza uma troca entre estudantes de diferentes níveis, bem como promove o professor ao patamar de mediador das situações de ensino-aprendizagem. As reflexões oportunizadas após cada momento vivenciado nas aulas e mediadas pelo professor constituirão em embasamento para a construção do conhecimento individual e coletivo. Dessa forma, o trabalho pretende despertar nos estudantes interesse nos conteúdos de termologia, incentivando, desse modo, a autonomia em pesquisar e descobrir e, ainda, melhorar o nível de instrução também de professores, fornecendo a estes subsídios para que o processo de ensino-aprendizagem ocorra satisfatoriamente dentro do conteúdo proposto.

Atualmente verificam-se inúmeras dificuldades encontradas pelos professores de ciências do 9º do Ensino Fundamental no processo ensino aprendizagem. Dentre elas destaca-se a não realização de aulas práticas, ocasionado pela falta de infraestrutura em algumas escolas, ou mesmo a falta de capacitação do professor para esse fim. Os conteúdos são trabalhados mecanicamente tendo somente o livro didático como apoio, o que produz um distanciamento do estudante com a disciplina de Física, desinteresse e consequentemente, baixo rendimento escolar (HARTMANN; ZIMMERMANN, 2009). Nesse contexto, oportunizar aos estudantes vivenciar as ciências, apoiando-se na história e descobertas de um grande Físico, como foi Isaac Newton, por meio da participação em uma feira de ciências, faz com que os mesmos assumam a condição de cientistas, investigadores e protagonistas na construção do conhecimento e pode tornar o processo de ensino aprendizagem mais atrativo e significativo. Em vista disso, propõe-se a elaboração de um Caderno Didático no intuito de orientar professores no planejamento, construção, organização e apresentação de uma feira de ciências com estudantes do 9º ano do Ensino Fundamental II, tendo como exemplos os experimentos do físico Isaac Newton e os princípios da Física Mecânica. Logo, a proposta didática tem como objetivo propiciar aos estudantes contato com experimentos, promovendo o trabalho em grupo, incentivando a pesquisa e a apresentação dos resultados obtidos, embasados no método científico, na feira de ciências, levando-os a conhecer Isaac Newton e suas contribuições para a ciência e relacionando-os com os fenômenos observados no cotidiano dos alunos. Sendo assim, seguirá um preceito educacional bem definido de que "a tendência atual da disciplina é fazer com que o aluno observe, pesquise em diversas fontes, questione e registre para aprender" (SANTOMAURO, 2009, p. 1). Além disto, a Teoria dos Modelos Mentais de Johnson-Laird será importante para o trabalho, pois ela nos faz entender que podemos capturar o que é comum de diferentes maneiras, dependemos apenas das possibilidades que nos cercam. Modelos Mentais são concepções a partir das experiências vividas por cada pessoa, em consonância ao que afirma Firmino, "Aprendemos desde a infância a raciocinar de acordo com padrões estabelecidos através de conhecimentos empíricos ou estabelecidos disciplinarmente." (FIRMINO, 2017, p. 6). Ninguém tem modelos sem finalidades ou compromisso, conforme diz Marco Moreira: Tal construção reflete uma intencionalidade do sujeito porque se ele constrói o modelo é porque quer dar conta da situação. Mas o modelo mental tem um único compromisso que é o da funcionalidade para o sujeito. Não implica, portanto, uma aprendizagem significativa no sentido de compartilhar significados, pois o modelo mental pode estar “errado” contextualmente, mas funciona bem para o sujeito. (MOREIRA, 2006, p. 07). Os modelos mentais são paralelos com a realidade, uma vez que estão na mente do indivíduo aguardando o momento certo de serem utilizados ou associados a eventos que necessitam de resposta imediata. Nesse sentido, os modelos mentais são importantes para o desenvolvimento deste trabalho, pois a intenção é de uma mudança conceitual alcançada por meio de enriquecimento reestruturado pelo novo conhecimento do aluno.

A presente pesquisa tem como objeto de estudo o ensino de óptica geométrica a partir de um kit contendo peças de acrílico (lentes e prismas), espelhos, laser, e outros materiais, cuja aplicação se orienta por princípios teóricos vygotskyanos, com objetivo de proporcionar a aprendizagem de estudantes do 2º ano do Ensino Médio, quando em contato com experimentos relacionados à luz. Os conteúdos abordados na aplicação do produto educacional são: reflexão e refração da luz, convergência e divergência, projeções com obstáculos, composição e decomposição da luz. Para o desenvolvimento dessa pesquisa será utilizada como base teórica a Teoria Sócio-Interacionista de Lev Vygotsky, haja vista que se trata de manuseio de instrumentos (objetos do kit), oralidade (arguições, falas dos alunos e do professor), esclarecimentos mais aprofundados por parte do professor, para compreender certos fenômenos e conceitos, quais os alunos não conseguem entender a princípio – utilizando-se dessa forma da Zona de Desenvolvimento Proximal – ZDP (PAULA, 2009). Barone (2011) ao abordar sobre a Psicologia sócio-histórica de Vygotsky comenta que os conceitos científicos são generalizados a partir de conceitos preliminares. A experiência, portanto, leva o experimentador a assimilar o novo com algo já conhecido. Sobre essa ótica, o professor atua como mediador, promovendo o contato entre o aluno e o objeto de pesquisa.

A Física em muitas escolas brasileiras é ensinada de forma descontextualizada, dando ênfase à memorização e aplicação direta de fórmulas, a própria carga horária impossibilita o aprofundamento e a introdução de certos conceitos. Muitos estudantes têm contato com conceitos de Física Moderna e Contemporânea (FMC) devido ao acesso aos meios de comunicação, o que torna esses conhecimentos parte do senso comum dos mesmos, cabendo à escola aperfeiçoar este conhecimento.

Os estudantes são naturalmente curiosos, utilizam diversas tecnologias em seu dia a dia e as aulas tradicionais não têm sido capazes de despertar o desejo em aprender. Em vista disso, aliar experimentação a tecnologias propicia a realização de atividades que desenvolvem a potencialidade do protagonismo juvenil e aprimoram o conhecimento, tornando o ensino realmente significativo. Atualmente os professores têm recorrido bastante a experimentos com materiais acessíveis. De acordo com Araújo e Abib (2003, p. 186) “uma modalidade de uso da experimentação que pode despertar facilmente o interesse dos estudantes relaciona-se à ilustração e análise de fenômenos básicos presentes em situações típicas do cotidiano” onde a partir da interação do indivíduo com a realidade do mundo que os cerca pode aumentar o interesse dos estudantes em sala de aula. No entanto, fora do ambiente escolar é necessário continuar mantendo esse interesse, a internet tem sido uma ótima aliada para fins de estudo, o que garante uma melhora no ensino-aprendizagem de física. Mas, se não houver uma orientação que aborde sobre os riscos de navegação nas redes, a internet pode tornar-se vilã, caso essa busca seja em websites não confiáveis. No âmbito da teoria de Ausubel (Moreira, 2006), recomenda o desenvolvimento de conceitos subsunçores que facilitem a aprendizagem subsequente. Nesse contexto, este trabalho busca inovar no ensino e aprendizagem em física, abordando temas de eletromagnetismo com metodologias diferenciadas, onde o estudante participa mais ativamente da construção do próprio conhecimento, não somente em sala de aula, mas também fora dela por meio de mídias audiovisuais. A ferramenta tecnológica empregada como produto educacional foi um website, contendo roteiros de aulas prontos para uso de docentes e discentes, sendo que o professor poderá baixá-lo e adaptar a sua realidade escolar e cultural. Tal ferramenta permite acesso à atividades a serem desenvolvidas em sala, além de artigos científicos, vídeos e experimentos criados pela autora e também os obtidos de fontes seguras e previamente analisados.

An integrated study including stratigraphy, composition and biostratigraphy was performed on temperate-type shallow-water carbonates of early middle Miocene age deposited in a wedge-top basin within the Apenninic chain (Romagna–Tuscan area). The succession rests unconformably on the deep-water sediments of allochthonous Ligurian units and is represented by up to 350 m thick carbonates and mixed siliciclastic-carbonate rocks. Two main units are recognized, each characterized by a distinct facies association. The basal unit (upper Burdigalian) consists of rhodalgal rudstones and packstones of shelf environment, dominated by echinoids, bryozoans, coralline algae and benthic foraminifera, deposited in temperate conditions and showing a transgressive pattern. It gradually passes into mixed carbonate-siliciclastic shallow water-facies, (Langhian in age) characterized by an increase in terrigenous components and planktonic and benthic taxa. Sediment starvation during the Langhian is suggested by the occurrence of glaucony-rich packstones with abundant planktonic foraminifera. The succession grades upwards into upper Langhian-lower Serravallian planktonic foraminifera-rich marls. Increasing detrital discharge and water depth up section results in drowning of the carbonate shelf. Debris-flow deposits including material of extraformational origin are intercalated at different levels, in particular from the uplifting south-western margins, close to the Ligurian thrusts. The inception and demise of these temperate rhodalgal-foramol carbonate sediments located in wedge-top Epiligurian basins are primarily controlled by synsedimentary tectonics, which in turn affects relative sea-level rise, and nutrient and detrital input. In particular, tectonics controlled the initial stage of the transgression, determining the configuration of the basin, subdivided in narrow submerged palaeotopographic lows and relatively elevated areas. Synsedimentary tectonics related to the thrust migration was also the main controlling factor in the demise of carbonate sedimentation, through the combined effect of two processes: increasing the subsidence of the basin, and triggering the terrigenous discharge from the erosion of the uplifted Apenninic relieves.

The Vicchio outcrop in the Tuscan Apennines contains excellent exposures of a Miocene methane-derived carbonate system, made up of more than 80 carbonate bodies enclosed in marly sediments. Facies analysis, composition and a detailed biostratigraphic study of the carbonates and enclosing Vicchio Marls allowed us to document the role of climatic changes and eustasy on seepage in these ancient deposits. Results of our study indicate that the stratigraphic horizon bearing seep-carbonates is constrained by two planktonic foraminiferal events, the Acme End (AE) of Turborotalita cf. T. quinqueloba (13.75 Ma) and the Acme 1 Beginning (A 1 B) of Paragloborotalia siakensis (13.32 Ma), encompassing about 400,000 years. The AE of T. cf. T. quinqueloba approximates the mid-Miocene global cooling event (Mi3b), as defined by the δ 18 O maxima (13.78 Ma). The glacio-eustatic sea level drop associated with this cooling event is estimated to be approximately 60 m. Assuming that the highest rates of glacio-eustatic sea level fall coincide with δ 18 O maxima, the timing of the seepage onset (at about 13.75 Ma) is concomitant with the phase of sea level-lowering. The ascent and emission of methane-rich fluids may have been triggered by pressure drop due to the eustatic fall associated with the Mi3b event. The moderate intensity of fluid expulsion is suggested by the lack of brecciation, by the scarcity of detrital particles in the carbonates and by the pervasive occurrence of carbonate in the enclosing marls. This type of seepage differs from focused fault-confined fluid flows, typical of other tectonically controlled Apenninic seep-carbonates.

Red stripe is a bacterial disease of sugarcane causing important economic losses in Argentina that affects 30 % of the milling stems and consequently the juice quality. In this study, sugarcane leaves exhibiting red stripe symptoms were sampled in the 2008?09 growing season from 13 different sugarcane producing areas of Tucumán and Salta (northwest of Argentina). To achieve the identification and characterization of the causal agent of red stripe, bacterial isolation was performed. Species-specific PCR using Oaf1/Oar1 primers allowed the amplification of a fragment of 550 bp from approximately 50%of the isolates; 16S rDNA sequences analysis displayed a similarity greater than 99 % with Acidovorax avenae subsp. avenae. By means of RAPDPCR the presence of at least four different biotypes among the analyzed isolates was detected. Results of pathogenicity test allowed us to confirm A. avenae subsp. avenae as the pathogenic agent for red stripe. This study constitutes the first report on the identification and molecular characterization of this plant pathogen from the Argentina sugarcane production areas. The genetic diversity observed among A. avenae is an important factor to be considered to improve an accurate diagnosis and/or the selection of sugarcane tolerant clones. Fil: Fontana, Paola Daniela. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucumán-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina; Fil: Rago, Alejandro Mario. Instituto Nacional de Tecnolog??­a Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Instituto de Patolog??­a Vegetal; Argentina; Fil: Fontana, Cecilia Alejandra. Universita Cattolica del Sacro Cuore; Italia; Fil: Vignolo, Graciela Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia Para Lactobacilos (i); Argentina; Fil: Cocconcelli, Pier S.. Universita Cattolica del Sacro Cuore; Italia; Fil: Mariotti, Jorge Alberto. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucumán-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina; Instituto Nacional de Tecnolog??­a Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Instituto de Patolog??­a Vegetal; Argentina

The Montardone melange (Mm) is a chaotic, block-in-matrix unit outcropping in the Montebaranzone syncline in the northern Apennines. The Mm occurs in the uppermost part of the Termina Fm, the Middle-Late Miocene interval of a succession deposited in a wedge-top slope basin (Epiligurian succession). The Mm is closely associated with bodies of authigenic carbonates, charac- terized by negative values of d 13 C (from -18.22 to -39.05 % PDB) and chemosynthetic benthic fauna (lucinid and vesicomyid bivalves). In this paper, we propose that the Mm is a mud volcano originated by the post-deposi- tional reactivation and rising of a stratigraphically lower mud-rich mass transport body (Canossa-Val Tiepido sed- imentary melange or olistostrome) triggered by fluid overpressure. We base our conclusion on (1) the Mm pierces the entire Termina Fm and older Epiligurian units and represents the direct continuation of the underlying Canossa-Val Tiepido melange; (2) the geometry and facies distribution of the Montebaranzone sandstone body, which are compatible with a confined basin controlled by the rising of the Mm; (3) the systematic presence of large-scale (lateral extension 300-400 m) seep-carbonates associated with the melange, suggesting a persistent gas-enriched fluid vent from the ascending overpressured mud; (4) blocks and clasts sourced from the Mm, hosted by the authigenic carbonates, conveyed by ascending mud and gas-enriched fluids. The Mm represents one of the few fossil examples of reactivation of a basin-scale sedimentary melange (olistostrome); a three-stage model showing mechanisms of Mm raising is proposed.

Excellent exposures of Miocene seep-carbonates enclosed in marine marly sediments (Vicchio outcrops in the northern Apennines, Italy) offer the opportunity to highlight the evolution of a fossil seep ecosystem and the response of benthic communities to high-stressed environmental conditions. For this purpose, seep-related facies and molluscs within carbonate bodies have been studied, coupled with benthic foraminiferal assemblages and carbon and oxygen isotopes in the enclosing marls. The integrated planktonic foraminiferal and calcareous nannofossil biostratigraphy has allowed us to constrain the seepage within well-calibrated bioevents and to stress the relationships with paleoclimatic and paleoceanographic variations during the middle Miocene in the Mediterranean area. Our biostratigraphic data indicate that the onset of the seepage approximates the Mi3b cooling event (13.82 Ma) and the seepage system lasts for 400 kyr. The evolution of the Vicchio cold-seep system passes through four phases: (1) The onset of the seepage, characterized by a pervasive flow of methane-rich fluids, is inferred by δ13C depletion of marly sediments and by prevailing benthic foraminifera indicative of suboxic conditions at the sea-floor. (2) The methane flow becomes focused causing the precipitation of wide pinnacle-like carbonate bodies which contain giants lucinids. Enclosing marls indicate well-oxygenated conditions, possibly enhanced by paleoceanographic variations connected to the Mi3b cooling event. (3) The appearance of the vesicomyid Christineconcha cf. C. regab and the absence of lucinids in seep-carbonates suggest stable methane-rich fluid emissions; higher flow rates locally favoured the flourishment of bacterial mats. Benthic foraminifera show abundance peaks of organic matter depending taxa. (4) The reduced intensity of methane-rich fluid flows favours the precipitation of stratiform carbonate bodies along strike; the macrofauna is characterized by the presence of both Vesicomyidae and giant lucinids. Foraminiferal assemblages in the enclosing marls indicate the restoration of well-oxygenated conditions.

In the Miocene of the northern Apennines of Italy, evolutionary phases of shallow-water carbonates in wedge-top basins are coeval with methane-rich fluid expulsion episodes in the inner foredeep. We identified four main correlative events, primarily controlled by synsedimentary tectonics, sediment input and climate cooling: 1) a Burdigalian tectonic phase determined the onset of shelfal sedimentation in wedge-top areas and is correlated with an important episode of fluid expulsion in marly sediments of the inner foredeep (Croce di Moggiona seep-carbonates); 2) the decrease of shelfal carbonate production and the increase of detrital input in the Early Langhian correspond with a second important episode of seep-carbonate precipitation in the inner foredeep (Castagno d'Andrea); 3) the demise of the carbonate shelf and the coeval expulsion of methane-rich fluids in the inner foredeep (Vicchio and M. Citerna seep-carbonates) at the Langhian/Serravallian boundary approximate the Mi3b cooling event. The lower temperatures, associated with increased siliciclastic weathering, led to the crisis of shallow-water carbonate production whereas the pressure drop due to the eustatic fall may have triggered the gas-charged fluid expulsion; 4) the tectonic-related uplift of frontal sectors of the wedge-top basin led to the wide erosion of the Burdigalian-Langhian carbonates and caused the precipitation of authigenic seep-carbonates (Deruta seep) both in the slope and the adjacent foredeep.

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Authigenic carbonates from outcrops of the northern Apennines consist of small and irregular lenses and exhibit numerous features indicative of cold-seep settings. Detailed petrographic, mineralogical and geochemical studies from two Miocene deposits are presented. The first carbonate outcrop, named Fosso Riconi, is located in the foredeep basin of the Apenninic chain, whereas the second deposit represents a satellite basin called Sarsetta. The stable isotope data from specific carbonate minerals show a wide range of values well known from other palaeoseeps of the Apennine Mountains. The majority of seep carbonates are formed by low-Mg calcite and ankerite. Those minerals have δ13C values between −7 and −23‰ V-PDB, suggesting variable amounts of carbonate derived from oxidized methane, seawater (dissolved inorganic carbon) and sedimentary organic matter. Dolomite samples have the lowest δ13C values (−30.8 to −39.0‰ V-PDB), indicating methane as the main carbon source. The findings suggest an evolutionary formation of the seeps and development of authigenic carbonates influenced by the activity of chemosynthetic organisms, of which large lucinid clams are preserved. Bioirrigation by the clams controlled the sediment–water exchange, and is here considered as an explanation for the anomalous Mg content of the calcite. We hypothesize that the seep carbonates were formed during periods of active methane-rich seepage, whereas during periods of slow seepage carbonate formation was reduced. Despite different geological settings, the two examined deposits of Sarsetta and Fosso Riconi show similar features, suggesting that a common pattern of fluid circulation played a major role in carbonate formation at both seep sites.

The Middle Miocene Marnoso-arenacea Formation at Deruta in the northern Apennines of Italy rests unconformably on an orogenic wedge adjacent to the Adriatic foredeep. Based on a detailed facies analysis, the succession reveals two genetically related depositional systems: a distal delta-fed sand-rich system and a more proximal fan-delta slope system. Petrographic data confirm the genetic relationship between the two depositional systems, with the fan-delta slope feeding the basinward sand-rich system. The Deruta depositional setting shows a multi-step sedimentary evolution controlled by tectonically induced relative sea-level changes. The first stage, corresponding to a sea-level rise, promoted deposition in a wedge-top basin of pebbly sand and sand lobes (delta-fed). The second stage, characterized by intense tectonic activity (uplift) and sea-level fall, promoted accumulation of a prograding fan-delta slope replacing the sand-rich lobes. This phase was dominated by mass failures and methanogenic cold seepages. During these two stages, the wedge-top basin was isolated from the adjacent foredeep. Only during the third stage was a connection established, with the development of a deep-sea fan in the foredeep, fed by a deltaic depositional system.