359 research outputs found

    Growth and subsidence of carbonate platforms: numerical modelling and application to the Dolomites, Italy

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    The phenomenon of subsidence induced by the growth of carbonate platforms has been investigated with the aid of numerical modelling. The research aimed to quantify the relative contribution of this process in the creation of the accommodation space required to pile up thick neritic bodies. We analysed two end-member deformation styles, namely the elastic behaviour of the lithosphere when locally loaded and the plastic-like reaction of a sedimentary succession underlying a growing carbonate buildup. The former process, analysed using a modified flexural model, generates a regional subsidence. In contrast, the latter process, simulated by considering the compaction occurring in soft sediments, generates a local subsidence. We attempted to quantify the amount and distribution of subsidence occurring below and surrounding an isolated platform and in the adjacent basin. The major parameters playing a role in the process are discussed in detail. The model is then applied to the Late Anisian-Early Ladinian generation of carbonate platforms of the Dolomites, Northern Italy, where they are spectacularly exposed. Taking also into account the Tertiary shortening that occurred in the area, both local and regional subsidence contributions of major platform bodies have been calculated aimed at a reconstruction of the map of the induced subsidence. A major outcome of this study is that the accommodation space, that allowed the accumulation of very thick shallow-water carbonate successions in the Dolomites, was only partially due to lithospheric stretching while the contribution given by the 'local' overload is as high as 20-40% of the total subsidence. Our results also shed some light on the water-depth problem of the Triassic basins as well as on the basin-depth to platform-thickness relationships

    Growth and subsidence of carbonate platforms: numerical modelling and application to the Dolomites, Italy

    Get PDF
    The phenomenon of subsidence induced by the growth of carbonate platforms has been investigated with the aid of numerical modelling. The research aimed to quantify the relative contribution of this process in the creation of the accommodation space required to pile up thick neritic bodies. We analysed two end-member deformation styles, namely the elastic behaviour of the lithosphere when locally loaded and the plastic-like reaction of a sedimentary succession underlying a growing carbonate buildup. The former process, analysed using a modified flexural model, generates a regional subsidence. In contrast, the latter process, simulated by considering the compaction occurring in soft sediments, generates a local subsidence. We attempted to quantify the amount and distribution of subsidence occurring below and surrounding an isolated platform and in the adjacent basin. The major parameters playing a role in the process are discussed in detail. The model is then applied to the Late Anisian-Early Ladinian generation of carbonate platforms of the Dolomites, Northern Italy, where they are spectacularly exposed. Taking also into account the Tertiary shortening that occurred in the area, both local and regional subsidence contributions of major platform bodies have been calculated aimed at a reconstruction of the map of the induced subsidence. A major outcome of this study is that the accommodation space, that allowed the accumulation of very thick shallow-water carbonate successions in the Dolomites, was only partially due to lithospheric stretching while the contribution given by the 'local' overload is as high as 20-40% of the total subsidence. Our results also shed some light on the water-depth problem of the Triassic basins as well as on the basin-depth to platform-thickness relationships

    WEBINAR UNTUK MERANCANG PERMAINAN MENYENANGKAN DI RUMAH PADA ANAK USIA DINI SELAMA MASA NEW NORMAL

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    Berdasarkan hasil survey di beberapa TK di wilayah kota Palembang ditemukan pembelajaran jarak jauh yang diberikan oleh guru lebih mengarahkan pada tugas mandiri pada peserta didik. Hal ini membuat banyak orangtua yang kewalahan mengerjakan tugas pada peserta didik dan khawatir anaknya belum bisa calistung. Tujuan webinar ini adalah mengedukasi orangtua untuk merancang pembelajaran menyenangkan selama masa new normal. Metode pelaksanaan dilakukan menggunakan webinar melalui aplikasi zoom cloud. Pelaksanaan dilakukan pada tanggal 20-21 November 2020. Narasumber adalah dosen psikologi dan praktisi anak usia dini, peserta pada hari pertama sebanyak 79 orang, hari kedua 45 peserta. Berdasarkan hasil evaluasi kegiatan, peserta mengaku memiliki penambahan pengetahuan untuk membuat kegiatan menyenangkan untuk anak usia dini. Kata kunci: Pembelajaran jarak jauh, New normal ABSTRACT Based on the survey results on several kindergartens in the Palembang, We found that the distance learning provided by the teacher was more directed at independent tasks for students. It made many parents overwhelmed with students' assignments and worry that their children cannot reading, writing and counting. The purpose of this webinar is  educating parents to design fun learning during  new normal period. The method of implementation is carried out using webinars via the zoom cloud application. The implementation was held on November 20-21, 2020. The speakers were psychology lecturers and early childhood practitioners, 89 participants on the first day, 42 participants on the second day. Based on the results of the activity evaluation, participants claimed to have added knowledge to make fun activities for early childhood. Keywords: Distance learning, New normal perio

    Distinct mouse bone marrow macrophage precursors identified by differential expression of ER-MP12 and ER-MP20 antigens

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    The characterization of early branch points in the differentiation of leukocytes requires identification of precursor cells in the bone marrow. Recently, we produced two monoclonal antibodies, ER-MP12 and ER-MP20, which in two-color flow-cytometric analysis divide the murine bone marrow into six defined subsets. Here we show, using fluorescence-activated cell sorting followed by macrophage colony-stimulating factor-stimulated culture in soft agar, that precursors of the mononuclear phagocyte system reside only within the ER-MP12hi20−, ER-MP12+20+ and ER-MP12−20hi bone marrow subsets. Together, these subsets comprise 15% of nucleated bone marrow cells. Furthermore, we provide evidence that the macrophage precursors present in these subsets represent successive stages in a maturation sequence where the most immature ER-MP12hi20− cells develop via the ER-MP12+20+ stage into ER-MP12−20hi monocytes

    Obesity as a social phenomenon: A narrative review

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    BACKGROUND: obesity is one of the most prevalent diseases all over the world. Because of its high social impact, the broadest possible approach on several levels - and not limited only to clinical aspect - is needed to better understand and face the challenges obesity poses to public health. OBJECTIVES: to analyse, through the main evidence, the so- cial impact of weight excess in the general population and the actions aimed at mitigating its negative effects. DESIGN: narrative review. SETTING: data obtained from the sources included in the study were gathered and analyzed in five macroareas: Health Inequality, Society, Work, Impact on Social Medicine (focused on the Italian model), and Social Costs. RESULTS: each category showed a bilateral relationship with obesity having a significant impact for the community. CONCLUSIONS: for each field, various actions should be taken at institutional level. Many recommendations and actions have already been taken worldwide, but they alone seem to be not enough. This work points out that, in order to combat obesity and bring about a slowdown of this pandemic, the en- tire scientific community and institutions must work together to identify and design programmes that are truly effective

    Successful Amelioration of Mitochondrial Optic Neuropathy Using the Yeast NDI1 Gene in a Rat Animal Model

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    Background: Leber’s hereditary optic neuropathy (LHON) is a maternally inherited disorder with point mutations in mitochondrial DNA which result in loss of vision in young adults. The majority of mutations reported to date are within the genes encoding the subunits of the mitochondrial NADH-quinone oxidoreductase, complex I. Establishment of animal models of LHON should help elucidate mechanism of the disease and could be utilized for possible development of therapeutic strategies. Methodology/Principal Findings: We established a rat model which involves injection of rotenone-loaded microspheres into the optic layer of the rat superior colliculus. The animals exhibited the most common features of LHON. Visual loss was observed within 2 weeks of rotenone administration with no apparent effect on retinal ganglion cells. Death of retinal ganglion cells occurred at a later stage. Using our rat model, we investigated the effect of the yeast alternative NADH dehydrogenase, Ndi1. We were able to achieve efficient expression of the Ndi1 protein in the mitochondria of all regions of retinal ganglion cells and axons by delivering the NDI1 gene into the optical layer of the superior colliculus. Remarkably, even after the vision of the rats was severely impaired, treatment of the animals with the NDI1 gene led to a complete restoration of the vision to the normal level. Control groups that received either empty vector or the GFP gene had no effects

    The T-box transcription factor Eomesodermin governs haemogenic competence of yolk sac mesodermal progenitors.

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    Extra-embryonic mesoderm (ExM)-composed of the earliest cells that traverse the primitive streak-gives rise to the endothelium as well as haematopoietic progenitors in the developing yolk sac. How a specific subset of ExM becomes committed to a haematopoietic fate remains unclear. Here we demonstrate using an embryonic stem cell model that transient expression of the T-box transcription factor Eomesodermin (Eomes) governs haemogenic competency of ExM. Eomes regulates the accessibility of enhancers that the transcription factor stem cell leukaemia (SCL) normally utilizes to specify primitive erythrocytes and is essential for the normal development of Runx1+ haemogenic endothelium. Single-cell RNA sequencing suggests that Eomes loss of function profoundly blocks the formation of blood progenitors but not specification of Flk-1+ haematoendothelial progenitors. Our findings place Eomes at the top of the transcriptional hierarchy regulating early blood formation and suggest that haemogenic competence is endowed earlier during embryonic development than was previously appreciated.We would like to acknowledge Michal Maj and Line Ericsen, and Kevin Clark in the flow cytometry facilities at the Dunn School and WIMM respectively for providing cell sorting services. The WIMM facility is supported by the MRC HIU; MRC MHU (MC_UU_12009); NIHR Oxford BRC and John Fell Fund (131/030 and 101/517), the EPA fund (CF182 and CF170) and by the WIMM Strategic Alliance awards G0902418 and MC_UU_12025. We thank Neil Ashley for his help on 10x sample preparation and sequencing. The WIMM Single Cell Core Facility was supported by the MRC MHU (MC_UU_12009), the Oxford Single Cell Biology Consortium (MR/M00919X/1) and the WT ISSF (097813/Z/11/B#) funding. The facility was supported by WIMM Strategic Alliance awards G0902418 and MC_UU_12025. We also thank the High-Throughput Genomics Group (Wellcome Trust (WT) Centre for Human Genetics, funded by WT 090532/Z/09/Z), for generating sequencing data. We thank Valerie Kouskoff for providing the iRunx1 ES cell line, Supat Thongjuea and Guanlin Wang for advice with the scRNA-Seq analysis, Joey Riepsaame for advice with CRISP-R experiments, and Doug Higgs, Hedia Chagraoui, Dominic Owens, Andrew Nelson and Arne Mould for helpful discussions. M.D.B and C.P are supported by programmes in the MRC Molecular Hematology Unit Core award (Grant number: MC_UU_12009/2 M.D.B. and MC_UU_12009/9 C.P.). L.G. was supported by a Clarendon PhD studentship and the MRC Molecular Haematology Unit. The work was supported by grants from the Wellcome Trust (214175/Z/18/Z E.J.R, 10281/Z/13/Z L.T.G.H). L.T.G.H was supported by a Clarendon Fund Scholarship and Trinity College Titley Scholarship. E.J.R. is a Wellcome Trust Principal Fellow

    Tracking early mammalian organogenesis – prediction and validation of differentiation trajectories at whole organism scale

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    Early organogenesis represents a key step in animal development, during which pluripotent cells diversify to initiate organ formation. Here, we sampled 300,000 single-cell transcriptomes from mouse embryos between E8.5 and E9.5 in 6-h intervals and combined this new dataset with our previous atlas (E6.5-E8.5) to produce a densely sampled timecourse of >400,000 cells from early gastrulation to organogenesis. Computational lineage reconstruction identified complex waves of blood and endothelial development, including a new programme for somite-derived endothelium. We also dissected the E7.5 primitive streak into four adjacent regions, performed scRNA-seq and predicted cell fates computationally. Finally, we defined developmental state/fate relationships by combining orthotopic grafting, microscopic analysis and scRNA-seq to transcriptionally determine cell fates of grafted primitive streak regions after 24 h of in vitro embryo culture. Experimentally determined fate outcomes were in good agreement with computationally predicted fates, demonstrating how classical grafting experiments can be revisited to establish high-resolution cell state/fate relationships. Such interdisciplinary approaches will benefit future studies in developmental biology and guide the in vitro production of cells for organ regeneration and repair
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