127 research outputs found

    First Occurrence of Tetrapod Footprints from Westphalian Strata of the Sidi Kassem Basin, Central Morocco

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    © 2014, Copyright © Taylor & Francis Group, LLC. The Sidi Kassem Basin is the only limnic basin of Westphalian age in Morocco. It is built up of 1,250 m of alluvio-fluvial to lacustrine deposits that have so far yielded plant fossils and invertebrate remains only. Recent exploration for fossil tetrapod footprints in floodplain-deposits of the basin revealed a moderately diverse vertebrate ichnofauna composed of tracks assigned to cf. Batrachichnus Woodworth, 1900; cf. Hylopus Dawson, 1882; Dimetropus Romer and Price, 1940; and Notalacerta Butts, 1891. The tracks can be referred to temnospondyl, anamniote reptiliomorph, non-therapsid synapsid (pelycosaur), and captorhinomorph trackmakers. The described ichnoassemblage is important in at least three aspects: (1) It suggests an Early to mid-Pennsylvanian age for the footprint-bearing strata of the study area. (2) It is the oldest association of tetrapod footprints from Africa. (3) It is the first evidence of the relatively rare ichnogenera cf. Hylopus and Notalacerta outside of North America and Europe. Judged from the variety of tetrapod tracks and previously collected floral remains, the Sidi Kassem Basin must have represented a well-established continental ecosystem during Pennsylvanian time. Further exploration for trace and body fossils of Palaeozoic vertebrates in this basin may be important for the reconstruction of early tetrapod evolution

    Middle to late Cambrian shallow marine trace fossils from the Imfout Syncline (Western Meseta, Morocco): Palaeoecological and palaeoenvironmental significance in NW-Gondwana

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    © 2017 Elsevier LtdThe present research provides the first evidence of invertebrate activity assigned to the ichnogenus Selenichnites occurring together with moderately diverse ichnofossils from the middle to late Cambrian of the Moroccan Meseta. The invertebrate traces occur in sandstone strata of the El Hank Formation within the Imfout Syncline, in the northern part of the Rehamna Massif (Coastal Block, western Moroccan Meseta). Bedding surfaces from the top of the El Hank Formation near the Imfout Dam show diverse forms of current ripples and distincts crescentic ichnofossils in concave epirelief scattered on the surface. In this section, the traces provide evidence of the ethology of an organism inhabiting the relatively shallow waters of the area during this time. Selenichnites co-occurs with the ichnogenera Arenicolites, Diplocraterion, Lingulichnus, Monocraterion, Skolithos and unidentified burrows, and the ichnoassemblage is referred to the Skolithos ichnofacies. These traces can be referred to arthropods (e.g. polychaete worms and amphipod crustaceans), lingulid brachiopods, annelids and/or phoronids. The Imfout Selenichnites represents the first occurrence of this ichnogenus from the Cambrian of the Moroccan Meseta, and the second from the Cambrian deposits of Morocco. The potential tracemakers are still questionable, but were most likely xiphosurans, trilobites, euthycarcinoids or crustaceans. If so, the Imfout traces could be among the oldest pieces of evidence for the presence of horseshoe crabs during the Cambrian. The combination of sedimentological and ichnological data indicates that the El Hank Formation was deposited in a sublittoral soft ground environment next to a sandy shore. It was originally part of an early Palaeozoic shallow marine epicontinental platform in west-central Morocco. In addition to the equivalent Cambrian deposits from the Anti-Atlas, the El Hank Formation constituted a part of the northern Gondwana platform domain during the transgression coming from the Rheic Ocean onto the West African Craton margin

    First occurrence of the Ichnogenus Selenichnites from the Middle Jurassic Strata of the Skoura Syncline (Middle Atlas, Morocco); Palaeoecological and palaeoenvironmental context

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    © 2015 Académie des sciences. Mesozoic strata of North Africa yield the first occurrence of the ichnogenus Selenichnites. The trace fossils occur on the top surface of a sandy carbonate deposit in the axis of a Middle Atlas syncline (Skoura Syncline, NE Morocco). The ichnofossil-bearing horizon belongs to the Late Bajocian-Early Bathonian Ich Timellaline/Bou Akrabene Formation. The trace fossils are crescent-shaped and the best preserved exhibits a posterior central axial impression (possible telson tail impression). They are interpreted as feeding burrows (fodinichnia) or hiding depressions of Xiphosurids or Limulids (horseshoe crabs) on a sandy carbonate substrate beneath a veneer of muddy deposits. The sedimentological character suggests a relatively protected shallow water subtidal palaeoenvironment preceding the Bathonian regression of the Atlas domain. This discovery provides the first evidence of xiphosurans or xiphosuran-like organisms inhabiting the southern shores of the Tethys in the Middle Jurassic

    New discoveries of archosaur and other tetrapod footprints from the Timezgadiouine Formation (Irohalene Member, Upper Triassic) of the Argana Basin, western High Atlas, Morocco - Ichnotaxonomic implications

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    © 2016 Elsevier B.V.New discoveries of tetrapod footprints from the Irohalene Member (T5, Upper Triassic, Carnian) of the Timezgadiouine Formation near Irohalene (Argana Basin, Morocco) are assigned to Parachirotherium isp., Atreipus-Grallator isp. (Dinosauromorpha), Brachychirotherium isp. (crocodylian-stem archosaurs), Apatopus lineatus (phytosaurs) and Rhynchosauroides (lepidosauromorphs/archosauromorphs). Parachirotherium is present on the surfaces with different tetradactyl-pentadactyl extramorphological variations, similar to the preservation mode observed at the type locality of the ichnogenus in the Middle Triassic of the European Germanic Basin. Described specimens permit a re-evaluation of footprints described earlier from the Irohalene locality that are synonymized here with Parachirotherium and Atreipus-Grallator. The presence of Brachychirotherium is the second record in North Africa and Morocco. The assemblage is similar in composition to other T5 localities and to some ichnofaunas in North America and central Europe. Biostratigraphically, the occurrence of Brachychirotherium indicates the respective biochron that can be cross-correlated with the Carnian-Rhaetian interval

    First occurrence of the Ichnogenus Selenichnites from the Middle Jurassic Strata of the Skoura Syncline (Middle Atlas, Morocco); Palaeoecological and palaeoenvironmental context

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    © 2015 Académie des sciences.Mesozoic strata of North Africa yield the first occurrence of the ichnogenus Selenichnites. The trace fossils occur on the top surface of a sandy carbonate deposit in the axis of a Middle Atlas syncline (Skoura Syncline, NE Morocco). The ichnofossil-bearing horizon belongs to the Late Bajocian-Early Bathonian Ich Timellaline/Bou Akrabene Formation. The trace fossils are crescent-shaped and the best preserved exhibits a posterior central axial impression (possible telson tail impression). They are interpreted as feeding burrows (fodinichnia) or hiding depressions of Xiphosurids or Limulids (horseshoe crabs) on a sandy carbonate substrate beneath a veneer of muddy deposits. The sedimentological character suggests a relatively protected shallow water subtidal palaeoenvironment preceding the Bathonian regression of the Atlas domain. This discovery provides the first evidence of xiphosurans or xiphosuran-like organisms inhabiting the southern shores of the Tethys in the Middle Jurassic

    Bird-like tracks from the imilchil formation (Middle jurassic, bajocian-bathonian) of the central high atlas, Morocco, in comparison with similar mesozoic tridactylous ichnotaxa

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    © 2017, Mucchi Editori s.r.l. All rights reserved. Small bird-like tracks have recently been discovered at three outcrops of the Imilchil Formation (Middle Jurassic, Bajocian-Bathonian) in the Central High Atlas of Morocco. The track-bearing strata are part of a marine-continental transitional succession, the studied surfaces being sandy marls and limestones of a brackish depositional environment. The footprints strongly resemble the ichnogenus Trisauropodiscus Ellenberger, 1970, from the Lower Elliot Formation (latest Triassic) of Lesotho, southern Africa and are assigned to Trisauropodiscus isp. These are functionally tridactyl, widely divaricated pes tracks with digit III being longest and a trace of the reverted digit I (hallux) being occasionally imprinted. In contrast to some former studies suggesting Trisauropodiscus as a junior synonym and extramorphological variation of the ornithischian ichnogenus Anomoepus, this ichnotaxon is considered here as a distinctive morphotype among similar theropod tracks found in Jurassic-Cretaceous ichnoassemblages. An amended diagnosis is proposed focusing on the features that are here discussed and considered as key characters of this ichnotaxon. An avian interpretation of the trackmaker is problematical, especially against the background of the stratigraphic range of Trisauropodiscus back to the Late Triassic. Presently, theropods with very bird-like feet are the more likely producers. Future analyses and comparison of Trisauropodiscus with pes skeletons of avian and non-avian theropods might enlighten this

    Late Carboniferous Tetrapod Footprints from the Souss Basin, Western High Atlas Mountains, Morocco

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    © 2017 Taylor & Francis Group, LLCThe Late Carboniferous Souss Basin of south-central Morocco exhibits an approximately 1,800 m thick succession of fluvial and lacustrine deposits that have yielded diverse fossil remains of plants, insects, conchostracans, ostracods, jellyfish, fishes, and few tetrapod footprints. Recent exploration of ichnofossils of the Souss Basin led to the discovery of several trampled surfaces including tetrapod footprints assigned to the plexus Batrachichnus (Woodworth, 1900). Limnopus (Marsh, 1894), Dimetropus (Romer and Price, 1940), and Ichniotherium (Pohlig, 1892). These footprints can be referred to temnospondyl, basal synapsid (“pelycosaurian”), and diadectomorph trackmakers. The moderately diverse tetrapod footprint assemblage from the Souss Basin is important because it is the second-oldest record of tetrapod footprints from Africa and only the second record of the well-known ichnogenus Ichniotherium from outside of North America and Europe. Based on the variety of tetrapod tracks and previously collected floral and insect remains, the Souss Basin must have represented a well-established continental ecosystem during the Late Carboniferous

    Prise en charge psychoéducative pour sevrage de benzodiazépines en cure thermale (et enquête auprès de médecins généralistes)

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    International audienceThe prevalence of benzodiapezine (BZD) consumption is assessed as 18.6% over 12 months and 11.3% over 30 days [1]. Within the framework of a transversal study with general practitioners (GP), 2000 GP representatives were picked by drawing lots. 300 provided information on 997 BZD-treated patients (15.6% patients/GP). 4.2% of the patients revealed the association of a length of treatment greater than recommended, with a notification to reduce or stop treatment by BZD, and others had expressed their wish to stop the treatment altogether. The weekly number of patients can be estimated at 47,189 for whom BZD withdrawal has been indicated. At the close of this work, a group of experts offered to draw up a procedure on in-care for BZD withdrawal in spa therapy for groups of 6 to 12 patients, stable regular BZD over-consumers for at least 3 months. This protocol associates daily crenotherapy treatment, personalized psychotherapeutic follow-up, consistent medical care and psycho-educative workshops. It is completed by a post-cure 6-month follow-up. There is an experimental phase under way in 2010 and 2011

    Use of CNS medications and cognitive decline in the aged: a longitudinal population-based study

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    <p>Abstract</p> <p>Background</p> <p>Previous studies have found associations between the use of central nervous system medication and the risk of cognitive decline in the aged. Our aim was to assess whether the use of a single central nervous system (CNS) medication and, on the other hand, the combined use of multiple CNS medications over time are related to the risk of cognitive decline in an older (≥ 65 yrs) population that is cognitively intact at baseline.</p> <p>Methods</p> <p>We conducted a longitudinal population-based study of cognitively intact older adults. The participants were 65 years old or older and had Mini-Mental State Examination (MMSE) sum scores of 24 points or higher. The study included a 7.6-year follow-up. The use of benzodiazepines and related drugs (BZDs), antipsychotics (APs), antidepressants (ADs), opioids (Ops), anticholinergics (AChs) and antiepileptics (AEs) was determined at baseline and after a 7.6-years of the follow-up period. Cognitive functioning was used as an outcome variable measured with MMSE at baseline and at the mean follow-up of 7.6 years. Control variables were adjusted with analyses of covariance.</p> <p>Results</p> <p>After adjusting for control variables, the use of Ops and the concomitant use of Ops and BZDs as well as the use of Ops and any CNS medication were associated with cognitive decline. The use of AChs was associated with decline in cognitive functioning only in men.</p> <p>Conclusions</p> <p>Of all the CNS medications analyzed in this study, the use of Ops may have the greatest effect on cognitive functioning in the ageing population. Due to small sample sizes these findings cannot be generalized to the unselected ageing population. More studies are needed concerning the long-term use of CNS medications, especially their concomitant use, and their potential cognitive effects.</p

    Benzodiazepine use among adults residing in the urban settlements of Karachi, Pakistan: A cross sectional study

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    <p>Abstract</p> <p>Background</p> <p>There are hardly any studies carried out in Pakistan on the usage of benzodiazepines at the level of community. This research was aimed to determine the frequency of benzodiazepine use, along with its associations with socio-demographic and clinical characteristics among community dwelling adults, residing in two urban settlements of Karachi, Pakistan.</p> <p>Methods</p> <p>We performed a cross sectional study from August 2008 to December 2009, in 2 areas of Karachi, namely Garden and Sultanabad. We followed the systematic sampling strategy to randomly select the households, with an adult of either sex and of age 18 years or more. Data collection was carried out through interview, using a pre-tested questionnaire, with items on socio-demographic position, medical history and benzodiazepine use. Student's t-test and χ<sup>2 </sup>test was employed to determine the associations between socio-demographic and clinical characteristics, and their relationship with benzodiazepine use was determined using applied logistic regression.</p> <p>Results</p> <p>The overall percentage of benzodiazepine consumption was estimated to be 14%. There were significantly more benzodiazepine users in the peri-urban Sultanabad community to the urban community of Garden (p-value = 0.001). The mean age (± SD) for users was 51.3 (± 15.6) years compared to 37.1 (± 14.4) years among non-users. Bromazepam was the most widely used benzodiazepine (29%); followed by diazepam, with a median duration on primary use being 144 weeks (IQR = 48-240). The adjusted logistic regression model revealed that increasing age, location, female sex, unemployment and psychiatric consultation were associated with increased likelihood of benzodiazepine use.</p> <p>Conclusion</p> <p>We believe the unregulated over-the-counter sales of benzodiazepines and social conditions might be playing a role in this high consumption of benzodiazepines in the community.</p
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