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Although rare, sedimentary deposits containing exceptionally preserved fossils (i.e., Lagerstätten) have shaped our view on the history of life at particular intervals, such as those recording the Cambrian radiation of animals. Therefore, understanding the processes that lead to the fossilization of unmineralized tissues is crucial to better interpret these fossil assemblages. A key issue on the fossilization of exceptionally preserved fossils is linked to the role of clay minerals in the high-fidelity preservation of recalcitrant and soft tissues. Here, we show for the first time, an association of unusual fibrous clays with carbonaceous fossils (Vendotaenia) in the late Ediacaran Tamengo Formation (Mato Grosso do Sul State, western Brazil). The vendotaeniaceans occur in laminated mudstones/siltstones interpreted as being deposited in outer to distal mid-ramp depositionary settings. The fossils are characterized by ribbon-shaped compressions 0.56 mm in mean width. The fibrous clays are obliquely oriented with respect to the bedding plane, and follow the orientation of tectonically deformed structures. Our mineralogical, geochemical, and petrographic data demonstrate that these clays are mainly composed of chlorite-smectite mixed layered minerals, with >50% chlorite. Altogether, our results suggest that these fibrous minerals formed in the late-diagenetic zone to lower anchizone, reinforcing the previous idea that clay minerals associated with fossils are not necessarily related to the preservation of soft tissues. Instead, the initial preservative pathway in our fossils was probably restricted to organic matter conservation in reducing fine-grained sediments, similar to other deposits with carbonaceous fossils. This newly established mechanism, which involves the formation of clays on organic templates in the late-diagenetic zone, is likely a more widespread phenomenon than previously thought.

Paleobiology is a worldwide known research area that concerns paleoecological, evolutionary and paleoenvironmental studies. Brazil has shown a great potential to the development of research that can contribute to the comprehension of evolutionary history of organisms. Brazilian vast territory holds many paleontological sites that keep crucial information about evolution and diversification of life on Earth. Some outcrops of Corumbá Group (Bocaina Formation) have evidences of first heterotrophic protists and also the following appearing of first metazoans that were capable of building skeletons (Tamengo Formation). Crato Member (northeastern Brazil) is worldwide known for its exceptional preservation of insects and plants and is one of the best sites to study insect-plant co-evolution. Other potential paleobiological field that has been developed in Brazil is paleomastozoology, whose fossils are especially abundant in the Pleistocene of many regions of Brazil and that can shed light about the extinction of megafauna and about its relationship with ancient human population. Therefore, Brazil has a quite complete fossil record that can help modern research, which will try to answer important evolutionary questions including those involving life mega-trajectories. A Paleobiologia é uma área que vem ganhando destaque mundial com seus estudos voltados para interpretaçõesecológicas, evolutivas e ambientais do registro fossilífero. Nesse contexto, o Brasil tem demonstrado grande potencial para odesenvolvimento de pesquisas que podem contribuir para compreensão da história e processos evolutivos dos organismos. Em seu vasto território, o país apresenta diversas localidades fossilíferas que contêm informações cruciais sobre a evolução ediversificação da vida na Terra. O Grupo Corumbá, em afloramentos da Formação Bocaina, apresenta evidências dos primeiros protistas eucariontes heterotróficos, além do posterior aparecimento dos primeiros metazoários capazes de realizaresqueletogênese, evidenciados na subsequente Formação Tamengo. O Membro Crato, no nordeste brasileiro, é reconhecidomundialmente pela preservação excepcional da paleoentomofauna e paleoflora do Cretáceo, e constitui uma das melhorespossibilidades para pesquisas paleontológicas voltadas para a coevolução inseto-planta. Outro grande campo da Paleobiologia que vem sendo desenvolvida no país são os estudos sobre a paleomastofauna, principalmente dos abundantes fósseis pleistocênicos encontrados em diversas regiões do país, e que podem lançar novas informações quanto a extinção da megafauna e a convivência desta com as antigas populações humanas da época. Sendo assim, o Brasil possui uma ampla gama temporal em seu registro fóssil, e permite o desenvolvimento de pesquisas de ponta que ajudarão a responder importantes questões evolutivas sobre os organismos, inclusive aquelas envolvendo as megatrajetórias da vida.

The early evolution of metazoans has been reconstructed by studies on exceptionally preserved molds in siliciclastic rocks from the Ediacaran Period. However, there remains considerable controversy regarding the formation mechanisms of this unusual ‘Ediacaran-style’ preservation. Proposed hypotheses usually include early authigenesis of minerals, but evidence for this is scarce. In a recently discovered deposit of Ediacaran biota in Brazil, we show that the classic moldic preservation is related to clay mineral authigenesis. Specifically, these clays originated from the alteration of original pyroclastic sediments, likely enhanced by microbial activity, leading to early illitization and morphological templating of the fossiliferous surfaces at a micrometric scale. Such high-fidelity preservation was made possible by rapid burial during volcanic events and the in-situ templating of tissue by clays via microbially-mediated mineralization. This newly described Lagerstätte demonstrates that a number of minerals can facilitate preservation, and that perhaps ‘Ediacaran-style’ preservation result from different processes leading to the same broad style of preservation.

Suplementary figures including field images, additional XRD patterns, MIR spectra, EDS and XRF elemental maps.

International audience; Biomineralized and organic metazoan tubular skeletons are by far the most common in the fossil record. However, several groups of organisms are also able to agglutinate particles to construct more rigid structures. Here we present a novel type of agglutinated tube from the austral and endemic palaeobiota of the Malvinokaffric realm (Devonian, Brazil). This fossil is characterized by an agglutinated tube made of silt-sized particles forming an unusual flanged morphology that is not known from the fossil record. Besides being able to select specific particles, these organisms probably lived partially buried and were detritus/suspension feeders. Comparisons across different modern groups show that these fossils are strongly similar to tubes made by polychaetes, specifically from the family Maldanidae. If this interpretation is correct, then an early divergence of the Sedentaria clade may have occurred before the Devonian.

Background: Synaptic proteins are increasingly studied as biomarkers for synaptic dysfunction and loss, which are early and central events in Alzheimer’s disease (AD) and strongly correlate with the degree of cognitive decline. In this study, we specifically investigated the synaptic binding partners neurexins (NRXN) and neuroligins (Nlgn), to assess their biomarker’s potential. Methods: We developed a parallel reaction monitoring mass spectrometric method for the simultaneous quantification of NRXNs and Nlgns in cerebrospinal fluid (CSF) of neurodegenerative diseases, focusing on AD. Specifically, NRXN-1α, NRXN-1β, NRXN-2α, NRXN-3α and Nlgn1, Nlgn2, Nlgn3 and Nlgn4 proteins were targeted. Findings: The proteins were investigated in a clinical cohort including CSF from controls (n=22), mild cognitive impairment (MCI) due to AD (n=44), MCI due to other conditions (n=46), AD (n=77) and a group of non-AD dementia (n=28). No difference in levels of NRXNs and Nlgns was found between AD (both at dementia and MCI stages) or controls or the non-AD dementia group for any of the targeted proteins. NRXN and Nlgn proteins correlated strongly with each other, but only a weak correlation with the AD core biomarkers and the synaptic biomarkers neurogranin and growth-associated protein 43, was found, possibly reflecting different pathogenic processing at the synapse. Interpretation: We conclude that NRXN and Nlgn proteins do not represent suitable biomarkers for synaptic pathology in AD. The panel developed here could aid in future investigations of the potential involvement of Nlgns and NRXNs in synaptic dysfunction in other disorders of the central nervous system. Funding: HZ is a Wallenberg Scholar supported by grants from the Swedish Research Council (#2018-02532), the European Research Council (#681712), Swedish State Support for Clinical Research (#ALFGBG- 720931), the Alzheimer Drug Discovery Foundation (ADDF), USA (#201809-2016862), the AD Strategic Fund and the Alzheimer's Association (#ADSF-21-831376-C, #ADSF-21-831381-C and #ADSF-21-831377-C), the Olav Thon Foundation, the Erling-Persson Family Foundation, Stiftelsen for Gamla Tjanarinnor, Hjarnfonden, Sweden (#FO2019-0228), the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 860197 (MIRIADE), and the UK Dementia Research Institute at UCL. KB is supported by the Swedish Research Council (#2017-00915), the Alzheimer Drug Discovery Foundation (ADDF), USA (#RDAPB- 201809- 2016615), the Swedish Alzheimer Foundation (#AF-742881), Hjarnfonden, Sweden (#FO2017-0243), the Swedish state under the agreement between the Swedish government and the County Councils, the ALF-agreement (#ALFGBG-715986), and European Union Joint Program for Neurodegenerative Disorders (JPND2019-466-236). The funders had no role in data collection, analysis, or decision to publish. EC received support from Gamla tjanarinnor, Stohnes stiftelse, Demensfonden and Emil och Maria Palms stiftelse. AV is supported by Fondation Ophtalmologique Adolphe de Rothschild, Fondation Chatrier and AAIHP association. Declaration of Interest: HZ has served at scientific advisory boards for Eisai, Denali, Roche Diagnostics, Wave, Samumed, Siemens Healthineers, Pinteon Therapeutics, Nervgen, AZTherapies and CogRx, has given lectures in symposia sponsored by Cellectricon, Fujirebio, Alzecure and Biogen, and is a co-founder of Brain Biomarker Solutions in Gothenburg AB (BBS), which is a part of the GU Ventures Incubator Program. KB has served as a consultant or at advisory board for Axon, Biogen, CogRx, Lilly, MegQu, Novartis and Roche Diagnostics. OH has acquired research support (for the institution) from Roche, Pfizer, GE Healthcare, Biogen, Eli Lilly and AVID Radiopharmaceuticals. In the past 2 years, he has received consultancy/speaker fees (paid to the institution) from Biogen and Roche. All other authors have nothing to declare. Ethical Approval: The use of these patient samples was approved by the Ethics Committee at the University of Gothenburg (EPN 140811).

Tau neurofibrillary tangles are key pathological features of Alzheimer’s disease and other tauopathies. Recombinant protein technology is vital for studying the structure and function of tau in physiology and aggregation in pathophysiology. However, open-source and well-characterized plasmids for efficiently expressing and purifying different tau variants are lacking. We generated 44 sequence-verified plasmids including those encoding full length (FL) tau-441, its four-repeat microtubule-binding (K18) fragment, and their respective selected familial pathological variants (N279K, V337M, P301L, C291R, and S356T). Moreover, plasmids for expressing single (C291A), double (C291A/C322A), and triple (C291A/C322A/I260C) cysteine-modified variants were generated to study alterations in cysteine content and locations. Furthermore, protocols for producing representative tau forms were developed. We produced and characterized the aggregation behavior of the triple cysteine-modified tau-K18, often used in real-time cell internalization and aggregation studies because it can be fluorescently labeled on a cysteine outside the microtubule-binding core. Similar to the wild type (WT), triple cysteine-modified tau-K18 aggregated by progressive β-sheet enrichment, albeit at a slower rate. On prolonged incubation, cysteine-modified K18 formed paired helical filaments similar to those in Alzheimer’s disease, sharing morphological phenotypes with WT tau-K18 filaments. Nonetheless, cysteine-modified tau-K18 filaments were significantly shorter (p = 0.002) and mostly wider than WT filaments, explainable by their different principal filament elongation pathways: vertical (end-to-end) and lateral growth for WT and cysteine-modified, respectively. Cysteine rearrangement may therefore induce filament polymorphism. Together, the plasmid library, the protein production methods, and the new insights into cysteine-dependent aggregation should facilitate further studies and the design of antiaggregation agents.\ud \ud

Neurogranin (Ng) is a 78 amino acid neuronal protein and a biomarker candidate for Alzheimer's disease (AD). Ng has been suggested to bind to calmodulin and phosphatidic acid via its centrally located IQ domain. Ng is cleaved within this functionally important domain, yielding the majority of fragments identified in cerebrospinal fluid (CSF), suggesting that cleavage of Ng may be a mechanism to regulate its function. Up to now, Ng has been shown to be present in CSF as both C‐terminal fragments as well as full‐length protein. To obtain an overview of the different molecular forms of Ng present in CSF, we show by size exclusion chromatography (SEC), immunoblotting, immunoprecipitation, and MS that Ng is present in CSF as several molecular forms. Besides monomeric full‐length Ng, also higher molecular weight forms of Ng, and C‐terminal‐ and previously not identified N‐terminal fragments were observed. We found by immunodepletion that C‐terminal peptides contribute on average to ~50% of the total‐Ng ELISA signal in CSF samples. There were no differences in the overall C‐terminal fragment/total‐Ng ratios between samples from AD and control groups. In addition, we found that monomeric Ng and its C‐terminal fragments bind to heparin via a heparin‐binding motif, which might be of relevance for their export mechanism from neurons. Taken together, this study highlights the presence of several molecular forms of Ng in CSF, comprising monomeric full‐length Ng, and N‐ and C‐terminal truncations of Ng, as well as larger forms of still unknown composition., C‐terminal fragments, along with full‐length forms of neurogranin (Ng) have been previously found at higher concentration in CSF from Alzheimer´s disease patients. Calpain 1 cleaves Ng in its IQ domain upon activation by Ca ions. This IQ domain is essential for modulating calmodulin and CaMKII signaling toward LTP. Using SEC, western blotting, and IP‐MS, we show that N‐terminal Ng and high molecular weight forms of Ng can be also be found in CSF. These Ng forms may have physiologic relevance and be of importance for the understanding of pathologic processes in brain disorders and for the development of specific biomarker assays.

Synapses are the site for brain communication where information is transmitted between neurons and stored for memory formation. Synaptic degeneration is a global and early pathogenic event in neurodegenerative disorders with reduced levels of pre- and postsynaptic proteins being recognized as a core feature of Alzheimer’s disease (AD) pathophysiology. Together with AD, other neurodegenerative and neurodevelopmental disorders show altered synaptic homeostasis as an important pathogenic event, and due to that, they are commonly referred to as synaptopathies. The exact mechanisms of synapse dysfunction in the different diseases are not well understood and their study would help understanding the pathogenic role of synaptic degeneration, as well as differences and commonalities among them and highlight candidate synaptic biomarkers for specific disorders. The assessment of synaptic proteins in cerebrospinal fluid (CSF), which can reflect synaptic dysfunction in patients with cognitive disorders, is a keen area of interest. Substantial research efforts are now directed toward the investigation of CSF synaptic pathology to improve the diagnosis of neurodegenerative disorders at an early stage as well as to monitor clinical progression. In this review, we will first summarize the pathological events that lead to synapse loss and then discuss the available data on established (eg, neurogranin, SNAP-25, synaptotagmin-1, GAP-43, and α-syn) and emerging (eg, synaptic vesicle glycoprotein 2A and neuronal pentraxins) CSF biomarkers for synapse dysfunction, while highlighting possible utilities, disease specificity, and technical challenges for their detection.

Made available in DSpace on 2020-12-12T02:40:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-08-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The Avalon biota (Ediacaran Period, 570–559 Ma) marks the first appearance of macroscopic and complex benthic communities in the fossil record. This assemblage is known from a few localities worldwide, mainly in Canada and England. Here, we report for the first time the presence of Ediacaran macrofossils in deposits of similar age from Gondwana (Itajaí Basin, southern Brazil). Our new radiometric date (~563 Ma) indicates that the Itajaí Basin can be chronocorrelated with the classic Avalonian deposits and thus represents one of the oldest records of the Ediacaran biota in Gondwana. We describe the presence of the Ediacaran genus Palaeopascichnus, as well as discs (Aspidella and Nimbia), and other problematic forms. Contrary to the deep-marine macroorganisms of the Avalon Assemblage, the Itajaí fossils are associated with abundant and exceptionally preserved three-dimensional microbial mats and microbially induced sedimentary structures (MISS) in relatively shallow settings (upper slope and distal delta front deposits). In this sense, the Itajaí biota could represent early adaptations of benthic macrobiota to the shallower and more photic environments that characterize the later White Sea Assemblage. Programa de Pós-Graduação em Ecologia e Recursos Naturais Universidade Federal de São Carlos, Washington Luiz, 325km Unité Mixte de Recherche (UMR) Centre National de la Recherche Scientifique (CNRS) IC2MP 7285 University of Poitiers Programa de Pós-Graduação em Geologia Universidade do Vale do Rio dos Sinos Petrobras Instituto de Geociências Universidade de São Paulo, Rua do Lago, 562, Cidade Universitária Petrobras Research Centre – CENPES Instituto de Geociências e Ciências Exatas (IGCE) Universidade Estadual Paulista (UNESP) Departamento de Biologia Universidade Federal de São Carlos – campus Sorocaba, Rod. João Leme dos Santos km 110 Instituto de Física Universidade de São Paulo, Rua do Matão, Travessa R 187 Instituto de Geociências e Ciências Exatas (IGCE) Universidade Estadual Paulista (UNESP) FAPESP: 2016/01827-4 FAPESP: 2018/21886-0

The Late Paleozoic Ice Age (LPIA) in Brazil has an extended sedimentary record, mainly in the Parana Basin. Ichnological records are the main biotic evidence in such an environment, and the Itarare Group (Parana Basin) is important in this regard. However, the Aquidauana Formation, one of the formations in the Itarare Group, is understudied regarding its trace fossil record. Thus, here we present the first ichnotaxonomic characterization of the Aquidauana Formation. We identified ten ichnospecies: Cruziana problematica, Cruziana cf. carbonaria, Diplichnites gouldi, Diplopodichnus biformis, Helmintoidichnites tenuis, cf. Kouphichnium isp., Monomorphichnus lineatus, Rusophycus carbonarius, Umfolozia sinuosa, and Warvichnium ulbrichi. Moreover, we also observed the presence of different morphotypes distributed among two ichnogenera: Monomorphichnus and Warvichnium. We also identified microbially induced sedimentary structures (Arumberia). According to these results, the paleoichnocoenosis of the Aquidauana Formation is characterized by the dominance of activity of small arthropods (probably benthic crustaceans), presenting a low richness of functional morphology. This depauperate ichnocoenosis may reflect environmental stress related to glacial environments and short colonization periods, corroborated by the absence of mixed-layer activity. Compared to other Gondwanic glacial deposits, the Aquidauana Formation is unique to present Warvichnium and Monomorphichnus. This unit also reveals a relationship with freshwater influence, similar to the Mafra Formation fjords in the southern Parana Basin. Thus, the Aquidauana Formation represents invertebrate colonization of submerged glacial freshwater environments in Gondwana, followed by subaerial exposure.

Studies regarding Quaternary mammals from the Serra da Bodoquena (South-western Brazil, state of Mato Grosso do Sul) are scarce. In the region, the Fadas Cave has been an important paleontological site. Remnants of Pleistocene fauna were collected along a river channel inside the cave. It is the first record of Arctotherium, Scelidotheriinae and Nothrotheriinae in the Serra da Bodoquena. Smilodon populator, Eremotherium laurillardi, Gomphotheriidae and Glyptodontinae, already known for the region, were also identified. These new occurrences allow us to redefine the paleozoogeographical distribution of some of the aforementioned taxa. Herein we propose the expansion of the range of the Brazilian Intertropical Region, which should include Mato Grosso do Sul and Sao Paulo. The state of Rio Grande do Sul keeps a greater paleozoogeographical affinity to others temperate zones from Argentina and Uruguay. Taxa associated to open environments indicate the existence of large areas of savannas during the late Pleistocene in the Serra da Bodoquena.

Synchrotron radiation (SR) is an electromagnetic radiation produced when electrons are forced to assume a curved trajectory resulting in an emission of a bright beam of high energy photons. This phenomenon is carried out in large particle acceleration facilities called synchrotrons, which is equipped with experimental stations at the end of each spot where the beam is emitted. In an applied sense, SR allows the investigation of materials of different nature, from synthetic to biological, from macro to the nano-scale. Since fossils are typified as environmental samples (i.e. a mixture of different type of compounds), SR has become an important approach to modern palaeontology. Due to the selective nature of the fossil record, bias can occur in both, morphology and geochemistry. Therefore, palaeontologists are frequently susceptible to equivocal interpretations. To diminish this problem, the employment of analytical methods became paramount in many areas of palaeontology. However, most benchtop equipments are limited in resolution, they also require particular experimental conditions (e.g. vacuum), and complex sample preparations (e.g. extraction from rocks). In this scenario, SR is advantageous as it allows non-destructive experiments to be performed in situ in qualitative or quantitative modes, in larger areas of the samples, still maintaining high spatial resolution and low detection limits. Nonetheless, in contrast to worldwide palaeontology where SR is widely applied, this analytical approach remains still poorly explored in South America. In Brazil, only a few studies used SR to resolve palaeontological problems. This panorama contrasts with the fact that in Brazil had a 2nd generation synchrotron, the UV and Soft X-Ray Light Source (UVX), which operated for 22 years. Nevertheless, this machine was substituted by a new 4th generation synchrotron, Sirius, which has been in operation since early 2020. Among its 13 beamlines, some will be best suitable to analyse palaeontological material, both through spectroscopy and imaging at a nanoscale. Therefore, it is expected that fossils will be routinely analysed in Sirius, being able to push forward the current knowledge in palaeontology. Here, we review the application of SR to the investigation of fossilization and other challenging topics in palaeontology. In this context, a fossil beetle from the Cretaceous Crato Formation (NE Brazil) was analysed using synchrotron radiation micro-X-Ray fluorescence (SR-μXRF). Results revealed which elements are involved in the process of fossilization and diagenesis, providing additional evidence for the preservational model of insects in this unit. Due to the high resolution and non-destructive properties, the SR-techniques have provided invaluable information on rare and delicate fossils. Considering all these aspects, it is now clear that this analytical approach has a high potential of expanding not only the frontiers of palaeontology, but also of the South American Earth sciences as a whole.

Precambrian filamentous microfossils are common and diverse. Nevertheless, their taxonomic assignment can be difficult owing to their overall simple shapes typically lacking in diagnostic features. Here, we report in situ communities of well-preserved, large filamentous impressions from the Ediacaran Itajaí Basin ( ca 563 Ma) of Brazil. The filaments are uniserial (unbranched) and can reach up to 200 µm in width and up to 44 mm in length. They occur as both densely packed or sparsely populated surfaces, and typically show a consistent orientation. Although simple in shape, their preferred orientation suggests they were tethered to the seafloor, and their overall flexibility (e.g. bent, folded and twisted) supports a biological (rather than sedimentary) affinity. Biometric comparisons with modern filamentous groups further support their biological affinity, suggesting links with either large sulfide-oxidizing bacteria (SOB) or eukaryotes. Other morphological and palaeoecological characteristics further corroborates their similarities with modern large filamentous SOB. Their widespread occurrence and association with complex Ediacaran macrobiota (e.g. frondose organisms, Palaeopascichnus ) suggest that they probably played an important role in the ecological dynamics of these early benthic communities by providing firm substrates for metazoans to inhabit. It is further hypothesized that the dynamic redox condition in the latest Ediacaran, with the non-continuous rise in oxygen concentration and periods of hypoxia, may have created ideal conditions for SOB to thrive.

Investigations into the existence of life in other parts of the cosmos find strong parallels with studies of the origin and evolution of life on our own planet. In this way, astrobiology and paleobiology are married by their common interest in disentangling the interconnections between life and the surrounding environment. In this way, a cross-point of both sciences is paleometry, which involves a myriad of imaging and geochemical techniques, usually non-destructive, applied to the investigation of the fossil record. In the last decades, paleometry has benefited from an unprecedented technological improvement, thus solving old questions and raising new ones. This advance has been paralleled by conceptual approaches and discoveries fuelled by technological evolution in astrobiological research. In this context, we present some new data and review recent advances on the employment of paleometry to investigations on paleobiology and astrobiology in Brazil in areas such biosignatures in Ediacaran microbial mats, biogenicity tests on enigmatic Ediacaran structures, research on Ediacaran metazoan biomineralization, fossil preservation in Cretaceous insects and fish, and finally the experimental study on the decay of fish to test the effect of distinct types of sediment on soft-tissue preservation, as well as the effects of early diagenesis on fish bone preservation.

Synaptic function and neurotransmitter release are regulated by specific proteins. Cortical neuronal differentiation of human induced pluripotent stem cells (hiPSC) provides an experimental model to obtain more information about synaptic development and physiology in vitro. In this study, expression and secretion of the synaptic proteins, neurogranin (NRGN), growth-associated protein-43 (GAP-43), synaptosomal-associated protein-25 (SNAP-25) and synaptotagmin-1 (SYT-1) were analyzed during cortical neuronal differentiation. Protein levels were measured in cells, modeling fetal cortical development and in cell-conditioned media which was used as a model of cerebrospinal fluid (CSF), respectively. Human iPSC-derived cortical neurons were maintained over a period of at least 150 days, which encompasses the different stages of neuronal development. The differentiation was divided into the following stages: hiPSC, neuro-progenitors, immature and mature cortical neurons. We show that NRGN was first expressed and secreted by neuro-progenitors while the maximum was reached in mature cortical neurons. GAP-43 was expressed and secreted first by neuro-progenitors and its expression increased markedly in immature cortical neurons. SYT-1 was expressed and secreted already by hiPSC but its expression and secretion peaked in mature neurons. SNAP-25 was first detected in neuro-progenitors and the expression and secretion increased gradually during neuronal stages reaching a maximum in mature neurons. The sensitive analytical techniques used to monitor the secretion of these synaptic proteins during cortical development make these data unique, since the secretion of these synaptic proteins has not been investigated before in such experimental models. The secretory profile of synaptic proteins, together with low release of intracellular content, implies that mature neurons actively secrete these synaptic proteins that previously have been associated with neurodegenerative disorders, including Alzheimer's disease. These data support further studies of human neuronal and synaptic development in vitro, and would potentially shed light on the mechanisms underlying altered concentrations of the proteins in bio-fluids in neurodegenerative diseases., Highlights • Human iPSC-derived cortical neurons express and secrete synaptic proteins. • NRGN, GAP-43 and SNAP-25 are first expressed and secreted by neuro-progenitors. • SYT-1 is expressed and secreted by stem cells. • Synaptic proteins are secreted the highest when mature cortical neurons are formed.

O objetivo do estudo foi apresentar uma descricao do novo Codigo Florestal Brasileiro (CFB) e comparar ao Codigo Florestal do Rio Grande do Sul, para evidenciar a necessidade de atualizacao do Codigo Florestal Estadual e apresentar propostas e alternativas para que o mesmo se adeque ao Novo Codigo Florestal vigente no Brasil. O trabalho visa subsidiar a compreensao de que com leis mais claras e que se apresentem de maneira mais coerente ao produtor rural, amplia-se a facilidade e conhecimento para as adequacoes da legislacao, e desta maneira sairem da ilegalidade, caso esse de muitos produtores rurais do Estado. Realizou-se a comparacao das leis que compoe os dois codigos, dividindo-se analises nos seguintes temas: Areas de Preservacao Permanente, Reserva Legal, Silvicultura, Areas Consolidadas e Fiscalizacao. Desta maneira, observou-se a necessidade da atualizacao do Codigo Florestal do Rio Grande do Sul, o qual apresenta-se com objetivos distintos quando comparado aos conceitos e interpretacoes do Novo Codigo Florestal vigente no Pais. Palavras-chave : legislacao ambiental, area de preservacao permanente, reserva legal. FOREST CODE OF RIO GRANDE DO SUL AND CONFLICTS WITH NEW BRAZILIAN FOREST CODE ABSTRACT The aim of the study was to present a description of the new Brazilian Forest Code (BFC) and compare the Forest of Rio Grande do Sul Code, to highlight the need to update the State Forest Code, to present proposals and alternatives for the same adjustment is in accordance with the current New Forest Code in Brazil. The work aims to subsidize the understanding that with clearer laws and put up more consistently to farmers way , extends to the ease and knowledge to the adequacy of the legislation, and thus leave the illegality, if that many farmers of State. It was performed to compare the laws that make up the two codes, dividing analysis on the following topics: Permanent Preservation Areas, Legal Reserve, Forestry, Consolidated and Inspection Areas. Thus, there was the need to update the Forestry Code of Rio Grande do Sul, as this presents with distinct objectives when compared to the concepts and interpretations of the New Forest Code in force in the country. Keywords: environment, permanent preservation area, legal reserve. DOI: http://dx.doi.org/10.5935/2318-7670.v05n01a08

The arrival of animals with hard parts at the end of the Ediacaran Period was an important evolutionary innovation. Biomineralized structures serve a number of biological functions and pose environmental challenges. Those same hard parts that once played a role in living organisms also affect their postmortem histories. Taphonomic scenarios may create biases that can impact perceptions on the systematic, morphological, biostratigraphic, and paleogeographic patterns in the fossil record. This is well exemplified by the taxonomic controversies regarding Cloudina, the most geographically widespread and abundant shelly fossil of the uppermost Ediacaran. In this study, we discuss new taphonomic data on Cloudina-bearing strata deposits from the Tamengo Formation (Corumba Group, Brazil) and how influential this taphonomy is on a robust taxonomy of this fossil. Our observations suggest that allochthonous Cloudina deposits from the Tamengo Formation present evidence of taphonomic influences on the transporting/reworking of fragmentation and disarticulation of Cloudina tubes. Differences in size distributions between some of the localities have demonstrated that this trait is not reliable for defining or synonymizing species of Cloudina, and these differences probably reflect a myriad of taphonomic and paleobiological phenomena. Moreover, in some outcrops of the Tamengo Formation, shell walls are usually poorly preserved due to plastic deformations and diagenetic dissolution/recrystallization processes, which conceal morphological diagnostic features used in Cloudina taxonomy. Similar taphonomic biases may be of equal importance to the taxonomy of Cloudina preserved in other upper Ediacaran carbonates. Hence, earlier claims in favor of the synonymization of Cloudina species from the Tamengo Formation cannot currently be justified.