13 research outputs found

    Global loss of avian evolutionary uniqueness in urban areas

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    Urbanization, one of the most important anthropogenic impacts on Earth, is rapidly expanding worldwide. This expansion of urban land-covered areas is known to significantly reduce different components of biodiversity. However, the global evidence for this effect is mainly focused on a single diversity measure (species richness) with a few local or regional studies also supporting reductions in functional diversity. We have used birds, an important ecological group that has been used as surrogate for other animals, to investigate the hypothesis that urbanization reduces the global taxonomical and/or evolutionary diversity. We have also explored whether there is evidence supporting that urban bird communities are evolutionarily homogenized worldwide in comparison with nonurban ones by means of using evolutionary distinctiveness (how unique are the species) of bird communities. To our knowledge, this is the first attempt to quantify the effect of urbanization in more than one single diversity measure as well as the first time to look for associations between urbanization and phylogenetic diversity at a large spatial scale. Our findings show a strong and globally consistent reduction in taxonomic diversity in urban areas, which is also synchronized with the evolutionary homogenization of urban bird communities. Despite our general patterns, we found some regional differences in the intensity of the effect of cities on bird species richness or evolutionary distinctiveness, suggesting that conservation efforts should be adapted locally. Our findings might be useful for conservationists and policymakers to minimize the impact of urban development on Earth's biodiversity and help design more realistic conservation strategies.Peer Reviewe

    Hemotympanum as a Complication of a Valsalva Maneuver during Childbirth

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    Background. Hemotympanum may occur due to otic barotrauma secondary to Valsalva maneuver during the second phase of labor. A pressure differential across the tympanic membrane (TM) of about five psi can cause rupture. The increased intrathoracic and intraabdominal pressure spikes repeatedly manifested by “pushing” during second-stage labor easily approach (and may exceed) this level. Clinical Presentation. This case report describes a healthy thirty-seven-year-old multipara patient admitted for the 40-weeks’ gestational age routine follow-up that proceeded to active labor followed by an aural fullness and bloody otorrhea. Otoscopic examination with a light microscope confirmed the hemotympanum of the right tympanic membrane. Conclusion. Forceful Valsalva can cause hemotympanum. Investigating the benefits and disadvantages of the pushing methods could help reduce such complications in the future. A prompt evaluation of an otolaryngologist should be requested in the event of a new postpartum hearing disturbance or bloody otorrhea

    Analysis of Prognostic Factors Impacting Pediatric Acute Mastoiditis Outcomes

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    Background: This study aimed to investigate the outcomes of pediatric patients with acute mastoiditis while examining the role of intravenous steroid therapy, patient demographics, and serum inflammatory values as prognostic factors. Methods: This study is a single-center retrospective observational study including 73 consecutive patients treated for acute mastoiditis in the course of the 10-year study period (January 2010 to December 2019). Results: Data analysis showed that patients requiring surgical treatment (14%) had a 3-fold higher C-reactive protein value at admission compared to those treated conservatively (P < .001). Receiver operating characteristic analysis revealed that a C-reactive protein cut-off of ≥98.7 had a sensitivity and specificity of 100% and 74.6%, respectively, for predicting the need for surgery (area under the curve=0.927, P < .001). The duration of symptoms before hospitalization was nearly 2 days shorter in male patients (P=.031), and the use of intravenous steroid therapy significantly shortened the length of hospitalization (P=.023), by 1.4 days on average. Conclusion: Intravenous steroid therapy may be useful in decreasing the length of hospital stay. Mastoiditis tends to present more severely in male patients, and monitoring C-reactive protein values during treatment correlated well with the need for surgery

    Urbanisation tolerance and the loss of avian diversity

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    Urbanisation is considered an important driver of current biodiversity loss, but the underlying causes are not fully understood. It is generally assumed that this loss reflects the fact that most organisms do not tolerate well the environmental alterations associated with urbanisation. Nevertheless, current evidence is inconclusive and the alternative that the biodiversity loss is the result of random mechanisms has never been evaluated. Analysing changes in abundance between urbanised environments and their non-urbanised surroundings of > 800 avian species from five continents, we show here that although random processes account for part of the species loss associated with urbanisation, much of the loss is associated with a lack of appropriate adaptations of most species for exploiting resources and avoiding risks of the urban environments. These findings have important conservation implications because the extinction of species with particular features should have higher impact on biodiversity and ecosystem function than a random loss.This work was supported by funds from the Spanish government (CGL2010-1838, ‘MONTES’ CSD2008-00040), Catalan government (2009SGR481) and Chilean government (CONICYT/FONDECYT postdoctorado 3130499).Peer reviewe
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