657 research outputs found

    A new species of Colostethus (Anura: Dendrobatidae) from the Cordillera de Mrida, northern Andes, South America

    Full text link
    http://deepblue.lib.umich.edu/bitstream/2027.42/57146/1/OP710.pd

    Eleutherodactylus colostichos, a new frog species from the Pramo de los Conejos, in the Venezuelan Andes (Anura: Leptodactylidae)

    Full text link
    http://deepblue.lib.umich.edu/bitstream/2027.42/57136/1/OP700.pd

    Ovarian reserve markers to identify poor responders in the context of poseidon classification

    Get PDF
    It is well-known that poor ovarian reserve is a cause of infertility, poor response to gonadotrophin stimulation and poor success rate after in vitro fertilization (IVF) cycles. Some years ago a consensus was elaborated on precise criteria which can lead to a correct identification of poor responders (the Bologna criteria). More recently, the POSEIDON group has proposed a new stratified classification of patients with low prognosis, also with the aim of providing clinical indications for the management of these patients. A literature search was carried out for studies that investigated the ability of ovarian reserve markers, in particular AMH and AFC, to predict poor ovarian response in IVF cycles; secondly, studies regarding the Bologna criteria and their prognostic value were analyzed and available literature on POSEIDON classification was reported. The most recent markers of ovarian reserve (serum AMH and ultrasound AFC) have shown to provide a direct and accurate measurement of ovarian follicle pool. These markers have generally shown comparable predictive power for ovarian response and a number of retrieved oocytes in IVF cycles. \u201cAbnormal ovarian reserve test\u201d is a very important parameter both in the Bologna criteria and in the POSEIDON classification. Several studies have already been published about the reproductive outcome of patients defined as poor responders according to the ESHRE Bologna criteria: all of them agree on the poor IVF outcome and low pregnancy rate of these patients. Instead, being the POSEIDON classification of very recent publication, the efficacy of the POSEIDON approach in improving management and outcomes of POR patients has yet to be tested and validated with future prospective clinical trials. Prediction of poor response may help clinicians choose the stimulation protocol with the aim of gaining patient compliance and cost reduction, and many efforts have been made by researchers in this sense, including the formulation of the Bologna criteria and of the POSEIDON classification, in which the ovarian reserve markers (AMH and AFC) play a fundamental role

    Genetic and morphological studies of Trichosirocalus species introduced to North America, Australia and New Zealand for the biological control of thistles

    Get PDF
    Trichosirocalus horridus sensu lato has been used as a biological control agent of several invasive thistles (Carduus spp., Cirsium spp. and Onopordum spp.) since 1974. It has been recognized as a single species until 2002, when it was split into three species based on morphological characters: T. horridus, Trichosirocalus briesei and Trichosirocalus mortadelo, each purported to have different host plants. Because of this taxonomic change, uncertainty exists as to which species were released in various countries; furthermore, there appears to be some exceptions to the purported host plants of some of these species. To resolve these questions, we conducted an integrative taxonomic study of the T. horridus species complex using molecular genetic and morphological analyses of specimens from three continents. Both mitochondrial cytochrome c oxidase subunit I and nuclear elongation factor 1α markers clearly indicate that there are only two distinct species, T. horridus and T. briesei. Molecular evidence, morphological analysis and host plant associations support the synonymy of T. horridus (Panzer, 1801) and T. mortadelo Alonso-Zarazaga & Sánchez-Ruiz, 2002. We determine that T. horridus has been established in Canada, USA, New Zealand and Australia and that T. briesei is established in Australia. The former species was collected from Carduus, Cirsium and Onopordum spp. in the field, whereas the latter appears to be specific to Onopordum

    Euclid preparation:XXVI. the Euclid Morphology Challenge: Towards structural parameters for billions of galaxies

    Get PDF
    The various Euclid imaging surveys will become a reference for studies of galaxy morphology by delivering imaging over an unprecedented area of 15 000 square degrees with high spatial resolution. In order to understand the capabilities of measuring morphologies from Euclid-detected galaxies and to help implement measurements in the pipeline of the Organisational Unit MER of the Euclid Science Ground Segment, we have conducted the Euclid Morphology Challenge, which we present in two papers. While the companion paper focusses on the analysis of photometry, this paper assesses the accuracy of the parametric galaxy morphology measurements in imaging predicted from within the Euclid Wide Survey. We evaluate the performance of five state-of-the-art surface-brightness-fitting codes, DeepLeGATo, Galapagos-2, Morfometryka, ProFit and SourceXtractor++, on a sample of about 1.5 million simulated galaxies (350 000 above 5s) resembling reduced observations with the Euclid VIS and NIR instruments. The simulations include analytic SĂ©rsic profiles with one and two components, as well as more realistic galaxies generated with neural networks. We find that, despite some code-specific differences, all methods tend to achieve reliable structural measurements (&lt; 10% scatter on ideal SĂ©rsic simulations) down to an apparent magnitude of about IE = 23 in one component and IE = 21 in two components, which correspond to a signal-to-noise ratio of approximately 1 and 5, respectively. We also show that when tested on non-analytic profiles, the results are typically degraded by a factor of 3, driven by systematics. We conclude that the official Euclid Data Releases will deliver robust structural parameters for at least 400 million galaxies in the Euclid Wide Survey by the end of the mission. We find that a key factor for explaining the different behaviour of the codes at the faint end is the set of adopted priors for the various structural parameters.</p

    TEVAR and periscope graft technique to treatment of huge aneurysm of aortic isthmus: Case report

    Get PDF
    Introduction: Thoracic endovascular aortic repair (TEVAR) has revolutionized the treatment of thoracic aortic aneurysms. Innovative techniques as chimney and periscope grafts can improve the outcomes of procedure. Herein, we report a case in emergency of huge Thoracic aortic aneurism. Presentation of case: An 86-year-old male with hypertension, diabetes mellitus, was referred to our hospital for chest pain. CT-angiography showed a huge aneurysm of aortic isthmus with signs of rupture. The patient was considered unfit for open surgery and an endovascular approach was chosen. This patient underwent endovascular repair with TEVAR, using the periscope graft technique to preserve patency in left subclavian artery (LSA). Discussion: Symptomatic ischemia from LSA coverage has been reported to occur in only a modest 6–10% of patients and is often sacrificed with impunity given coverage rates between 10 and 50%. In this case reported the lack of revascularization of LSA increased the risk of neurological manifestations or stroke. Periscope technique is feasible and safe to maintain perfusion to the subclavian artery, with a 93% primary patency at 2 years. Conclusions: Our experience using TEVAR with periscope graft technique as solution to address thoracic aneurysm of aortic isthmus was feasible and safe
    • …
    corecore