Homenagem póstuma - Rafael Gioia Martins Neto

Homenagem póstuma - Rafael Gioia Martins NetoHomenagem póstuma - Rafael Gioia Martins Net

Editorial

 Estimados lectores de LAJSBA, como saben, nuestra revista ha renovado su equipo editorial para el período 2018-2022. Como Editor (Sebastian Richiano) y Editores Asociados (Renata Netto y Fernando Gómez), queremos contactarnos con ustedes por primera vez, en este caso iniciando el Volumen 25. Nos gustaría agradecer a la Comisión Directiva de la Asociación Argentina de Sedimentología por confiar en nosotros para esta tarea tan importante y comprometida. La revista, desde su inicio en 2005 (en continuación de la AASRevista que se publicara desde 1994), ha ido mejorando progresivamente su calidad y su visibilidad dentro de la comunidad científica. Esto se debe principalmente al esfuerzo de los diferentes equipos editoriales y, en este sentido, nos gustaría agradecer al ex editor Ernesto Schwarz y a la ex editora asociada Diana Cuadrado por su importante labor durante los últimos 4 años

Editorial

Dear LAJSBA readers, we want to stay in contact with you for the second time, in this case starting the 27th Volume and after two years as LAJSBA Editors. First of all, we would like to thank the support received by the broad sedimentological community in Argentina and Latin America, particularly to the affiliates of the Asociación Argentina de Sedimentología. The journal has experienced important advances in these two years which are our main focus on this communication. In our first Editorial, in Vol. 25.1, we put emphasis in some relevant topics to work for during this time. One of them was the possibility of incorporate the complete record of the AAS Revista (pre-LAJSBA) to SCOPUS. This finally was achieved by the end of 2019, and SCOPUS database included all the papers from AAS-Revista between 1996-2004. To do this, very important steps were done by members of the AAS board and previous editorial teams, so thanks to them! Another previously mentioned aspect was the incorporation of a Digital Object Identifier (DOI) for all the papers of the journal. This theme is on progress at this moment through Scielo Argentina, they will generate DOI’s for LAJSBA papers before 2020, after that we will continue the process. Apart from these two topics, may be the most important news for LAJSBA is the regularity of the volumes! After a 2018 with a record of papers submitted to the journal we could publish 4 full numbers in a year (25.1, 25.2, 26.1 and 26.2) which means that in December 2019 we publish on-line and on-time the Volume 26.2. In the same way, the present number (27.1) is fully available on-line in July 2020 on our final repository, Scielo Argentina.Special thanks are for Augusto Varela and José Cuitiño, guest editors of the two highly successful Special Volumes dedicated to the Austral Basin. We invite to our readers to propose new thematic volumes for LAJSBA. Nowadays the LAJSBA is an entirely online-only free-access journal, with a high level of scientific quality and design which is recognized for the Latin American Earth-science community. In terms of bibliographic indexes, LAJSBA is taken into account by SCOPUS, Scimago, Latindex, GeoRef, and SciELO. Considering the recent modification of SCOPUS’s CiteScore, LAJSBA maintain its status in the 3rd Quartile in the Scimago Journal Ranking in all the categories where it is included (Geology, Paleontology, and Stratigraphy). We strongly believed that LAJSBA is ready to jump to the next level, becoming more attractive for the international community. We will work to maintain the path marked by previous editorial teams for this journal. To conclude, we want to emphasize that the future of LAJSBA depends on all of us, readers, authors, reviewers, and editors. The journal needs the support of the Latin American sedimentological community, not just to maintain its importance in our region, but to cross our borders. A special message is for our readers; we are looking forward to receiving your contributions

Assinaturas icnológicas da sucessão sedimentar Rio Bonito no bloco central da jazida carbonífera de Iruí, Cachoeira do Sul (RS)

The subsurface deposits of the Rio Bonito sedimentary succession in the central block of the Iruí coal mine (Cachoeira do Sul, Rio Grande do Sul State, S Brazil) is composed of sedimentary facies associations that represent deposition in dominantly marginal-marine and shallow-marine settings, the later in minor scale. Ichnofabrics of Chondrites, Chondrites-Helmintopsis-Planolites, Cylindrichnus-Thalassinoides, Helminthopsis, Macaronichnus, Ophiomorpha, Palaeophycus, Planolites, Thalassinoides, and Thalassinoides-Palaeophycus occur in the marginal marine settings, whereas the Thalassinoides-Palaeophycus-Helminthopsis ichnofabric is present in the shallow marine deposits. The marginal-marine ichnofabrics are characterized by the low bioturbation index, the reduced size of burrows, and the low ichnodiversity, whereas the marine ones show a moderate to high degree of bioturbation and low ichnodiversity. The ichnofabric pattern, its stratigraphic distribution, and its sedimentological relationships allow recognizing four ichnological signatures, three suggesting stress caused by changes in the salinity gradient, and one substrate-controlled. Ichnofabrics of Helmithopsis, Palapeophycus, and Planolites in lithofacies SiltArg suggest the dominance of oligohaline to freshwater conditions. Ichnofabrics of Thalassinoides-Palaeophycus and Cylindrichnus-Thalassinoides refl ect the dominance of mesohaline conditions, each one representing, respectively, more quiet and stable environments (impoverished Cruziana Ichnofacies suite), and moderate to high energy settings (mixed Skolithos-Cruziana Ichnofacies suite). The Thalassinoides-Palaeophycus-Helminthopsis ichnofabric represents an arquetypical Cruziana Ichnofacies suite, indicating shallow marine settings. The reduced size of the burrows, however, suggests dominance of polyhaline rather than stenohaline conditions and its local distribution allow infer deposition in embayments, which mimic the environmental conditions found in the lower shorefce/ offshore transition zones. The Thalassinoides ichnofabric is substrate-controlled, representing a Glossifungites Ichnofacies suite. It demarks two autogenic stratigraphic surfaces, and one allogenic stratigraphic surface interpreted as a sequence boundary. The integrated ichnological and sedimentological analysis in high resolution scale, allowed refining the existent paleoenvironmental and stratigraphic interpretations of the Rio Bonito sedimentary succession in the study area. Key words: ichnology, sedimentology, ichnofabrics, ichnological signatures, coastal deposits.Icnofábricas de Chondrites, Chondrites-Helmintopsis-Planolites, Cylindrichnus-Thalassinoides, Helminthopsis, Macaronichnus, Ophiomorpha, Palaeophycus, Planolites, Thalassinoides, Thalassinoides-Palaeophycus e Thalassinoides-Palaeophycus-Helminthopsis foram reconhecidas em depósitos costeiros e marinhos rasos da sucessão sedimentar Rio Bonito, no bloco central da jazida carbonífera de Iruí (Cachoeira do Sul, RS). As associações de fácies de depósitos costeiros caracterizam-se pelo índice de bioturbação baixo, pelo tamanho reduzido das escavações e pela icnodiversidade baixa, enquanto nos depósitos marinhos rasos apresentam índice de bioturbação moderado a alto e maior icnodiversidade. O padrão de cada icnofábrica, sua distribuição estratigráfica e seus vínculos faciológicos permitiram reconhecer quatro assinaturas icnológicas principais, três delas indicativas de estresse por salinidade e uma substrato-controlada. As icnofábricas de Helmithopsis, Palapeophycus e Planolites sugerem o domínio de águas oligoalinas a doces. As icnofábricas de Thalassinoides-Palaeophycus e Cylindrichnus-Thalassinoides refl etem águas mesoalinas, e representam respectivamente, uma suíte de ambientes mais estáveis e com menor energia (suíte empobrecida de Icnofácies Cruziana) e uma suíte de ambiente com maior energia (suíte de icnofácies mista Skolithos-Cruziana). A icnofábrica Thalassinoides-Palaeophycus-Helminthopsis caracteriza uma suíte marinha rasa de Icnofácies Cruziana; o tamanho reduzido das escavações, contudo, sugere domínio de águas polialinas, e a ocorrência pontual das icnofábricas, a deposição em enseadas que mimetizariam as condições ambientais encontradas na zona de shoreface inferior/transição ao offshore. A icnofábrica de Thalassinoides é substrato-controlada e ocorre em contexto de Icnofácies Glossifungites, demarcando duas superfícies estratigráficas autogênicas e uma alogênica. A análise integrada e em alta resolução dos depósitos estudados, permitiu refinar as interpretações paleoambientais e estratigráficas para a sucessão sedimentar Rio Bonito na área de estudo. Figura Complementar 1. Figura Complementar 2.Palavras-chave: icnologia, sedimentologia, icnofábricas, assinaturas icnológicas, depósitos costeiros

Icnofósseis em afloramentos do Rio Grande do Sul: nota preliminar

O trabalho não apresenta resumo

Study protocol for the multicentre cohorts of Zika virus infection in pregnant women, infants, and acute clinical cases in Latin America and the Caribbean: The ZIKAlliance consortium

Background: The European Commission (EC) Horizon 2020 (H2020)-funded ZIKAlliance Consortium designed a multicentre study including pregnant women (PW), children (CH) and natural history (NH) cohorts. Clinical sites were selected over a wide geographic range within Latin America and the Caribbean, taking into account the dynamic course of the ZIKV epidemic. Methods: Recruitment to the PW cohort will take place in antenatal care clinics. PW will be enrolled regardless of symptoms and followed over the course of pregnancy, approximately every 4 weeks. PW will be revisited at delivery (or after miscarriage/abortion) to assess birth outcomes, including microcephaly and other congenital abnormalities according to the evolving definition of congenital Zika syndrome (CZS). After birth, children will be followed for 2 years in the CH cohort. Follow-up visits are scheduled at ages 1-3, 4-6, 12, and 24 months to assess neurocognitive and developmental milestones. In addition, a NH cohort for the characterization of symptomatic rash/fever illness was designed, including follow-up to capture persisting health problems. Blood, urine, and other biological materials will be collected, and tested for ZIKV and other relevant arboviral diseases (dengue, chikungunya, yellow fever) using RT-PCR or serological methods. A virtual, decentralized biobank will be created. Reciprocal clinical monitoring has been established between partner sites. Substudies of ZIKV seroprevalence, transmissio

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

The Mesozoic marine revolution

The Mesozoic Marine Revolution (MMR) was a major evolutionary episode involving the large-scale restructuring of shallow-marine benthic communities and the rise to dominance of the Modern Evolutionary Fauna. Although the majority of studies published on the MMR have been based on the body-fossil record, the ichnologic record yields valuable insights into this evolutionary event, most notably regarding the degree of infaunalization, complexity of infaunal tiering structures, and predation intensity. The main groups of bioturbators involved in the MMR were crustaceans, bivalves, echinoids, and “worms,” whereas the most important bioeroders were sponges, gastropods, bivalves, echinoids, and “worms.” The Triassic, encapsulated between two major mass extinctions, can be regarded as setting the stage for the MMR. The sparse ichnologic information available suggests that full recovery from the end-Permian mass extinction had taken place in equatorial carbonate settings by the Middle Triassic, although ichnofaunas show limited infaunalization and relatively simple tiering structures. However, a few key players, most notably some decapod crustaceans, were already dominant in carbonate settings. Jurassic ichnofaunas reveal a compositional turnover, signaling the rise to dominance of the Modern Evolutionary Fauna. This faunal turnover occurred by the Early Jurassic, as indicated by the taxonomic composition and increased diversity of bioturbation structures and the complexity of infaunal tiering. During the Cretaceous, a continuation of the trends established in the Jurassic was recorded. However, by the end of the Cretaceous, a modern-style benthic–pelagic coupling pattern was established, accompanied by an increase in global ichnodiversity. Rapid development of coccolithophores provided a new substrate (chalk) and an increasing flux of organic matter to the seafloor, enabling establishment of complex tiering structures, unknown in older deposits. The degree of macrobioerosion indicates an increasing participation of some players typical of modern communities. Paleogene bioturbation structures are similar to those of the late Mesozoic. Macrobioerosion styles also persisted across the Cretaceous–Paleogene boundary, albeit with an increased role for bioerosion by sponges and fishes later in the Paleogene. Predation pressures (drilling and durophagy) increased during the Eocene. Ichnofaunas in shallow-marine sediments record continued expansion of diversity during the Neogene, as well as more complex tiering structures. Predation pressure continued to rise, involving primarily marine mammals. Although the MMR for the most part took place in shallow, fully marine settings, the trace-fossil record also provides evidence for its expression in the deep sea and marginal-marine, brackish-water settings. Irregular echinoids and decapod crustaceans apparently had migrated to the deep sea by the Late Jurassic, whereas most of the main players of the MMR in fully marine settings (e.g., decapod crustaceans, bivalves, worms) were also dominant in brackish-water settings since the beginning of this major evolutionary event. Trace-fossil data indicate that infaunalization predates an increase of predation pressures by approximately 50 Myr, suggesting a complex set of feedback mechanisms between predation and infaunalization rather than simple cause and effect between the two. Turnover in ichnofaunal composition and the increased infaunalization that took place during the MMR strongly supports the “bulldozing hypothesis” (the notion that biological disturbance increased through the Phanerozoic), indicating a dramatic rise in bioturbational sediment processing by elements of the Modern Evolutionary Fauna.Fil: Buatois, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. University of Saskatchewan; CanadáFil: Carmona, Noelia Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Universidad Nacional de Río Negro. Sede Alto Valle. Instituto de Investigaciones en Paleobiología y Geología; ArgentinaFil: Curran, H. Allen. Smith College. Department of Geosciences; Estados UnidosFil: Netto, Renata G.. Universidad de Vale do Rio dos Sinos; BrasilFil: Mangano, Maria Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. University of Saskatchewan; CanadáFil: Wetzel, Andreas. Universität Basel. Geologisch-Paläontologisches Institut; Suiz

Scratching the discs: evaluating alternative hypotheses for the origin of the Ediacaran discoidal structures from the Cerro Negro Formation, La Providencia Group, Argentina

In the Ediacaran marine succession of the Cerro Negro Formation (Tandilia System, NE Argentina), abundant microbially induced sedimentary structures indicate general conditions of substrate biostabilization. Numerous discoidal structures in this succession were previously interpreted as moulds of soft-tissue holdfasts of sessile organisms, within the form genus Aspidella. In this study, we performed a detailed re-analysis of some of these features and discuss two alternative hypotheses to explain their genesis: (1) as the result of soft-sediment deformation and fluid injection structures; and (2) as structures of active animal–sediment interaction (i.e. trace fossils). We show that the dome-shaped discs are internally laminated, with a cylindrical to a funnel-shaped vertical tube at their central region. The presence of these downwards vertical extensions and other intricate internal arrangements cannot be explained under the taphonomic spectrum of discoidal fossils, but shows striking similarities to Intrites-like structures and other sand-volcano-like pseudofossils (e.g. Astropolithon). However, some structures are hard to distinguish from vertical dwelling burrows with funnel-shaped apertures and thick-lined walls, commonly produced by suspension- and detritus-feeding invertebrates (e.g. Skolithos isp., Monocraterion isp. and, less likely, Rosselia isp.). Since reliable age constraints are unavailable, and further investigation concerning other palaeobiological indicators is needed, the most parsimonious hypothesis is that of a structure derived from fluid-escape processes. Our study demonstrates the importance of detailed investigation on discoidal structures in either upper Ediacaran or lower Cambrian strata.Fil: Inglez, Lucas. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Warren, Lucas V.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Quaglio, Fernanda. Universidade Federal de Sao Paulo; BrasilFil: Netto, Renata G.. Universidad de Vale do Rio dos Sinos; BrasilFil: Okubo, Juliana. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Arrouy, Maria Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Rectorado. Instituto de Hidrología de Llanuras - Sede Azul. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Hidrología de Llanuras - Sede Azul; ArgentinaFil: Simões, Marcello G.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Poiré, Daniel G.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentin

Comparative study of epidural xylazine or clonidine in horses

Objective To evaluate the cardiorespiratory and behavioural effects of epidural xylazine (XYL) or clonidine (CLO) in horses.Study design Blinded, randomized experimental study.Twelve healthy Arabian yearling horses weighing 117-204 kg were randomly allocated into two groups: XYL (n = 6) and CLO (n = 6).Methods An epidural catheter was inserted and a facial arterial catheter was placed and the next day the horses were restrained in stocks. Baseline values for heart (HR) and respiratory (RR) rates, arterial pressure and behavioural responses were evaluated before (TO) and 10, 20, 30, 45, 60, 90 and 120 minutes after epidural injection (T10-T120). The horses received 0.2 mg kg(-1) of XYL or 5 mu g kg(-1) CLO; adjusted to (3.4 + (body weight in kg x 0.013) mL with saline. Data were analysed by the Kolmogorov-Smirnov test, one-way ANOVA with repeated measures, and one-way ANOVA followed by a Student-Newman-Keuls test or Fisher's exact test, as necessary. Significance was set at p <= 0.05.Results Sedation and ataxia were seen at T10, persisting until T120 in four and three horses, respectively, in XYL and all horses in CLO respectively. Two XYL and one CLO horses became recumbent at T45 and T25 respectively. Penile prolapse occurred in four of five males at T30 and T45, in the XYL and CLO groups, respectively, resolving by T120. Tail relaxation was present from T10 to T120 in all horses in XYL and in four horses in CLO. Head drop was observed from T20 to T60 and from T10 to T120 in XYL and CLO respectively. Respiratory rate decreased significantly only at T45 in the CLO group. Heart rate and arterial blood pressure remained stable.Conclusions and clinical relevance Epidural CLO and XYL produce similar cardiorespiratory and behavioural changes but neither would be safe to use clinically at the doses used in this study