738 research outputs found

    Incidence and distribution of Heterobasidion and Armillaria and their influence on canopy gap formation in unmanaged mountain pine forests in the Swiss Alps

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    Various disturbance factors on different spatial scales can lead to the creation of canopy gaps in forest ecosystems. In this study, we investigated the role of root rot fungi in the formation of canopy gaps in the Swiss National Park in the Central Alps. Dying or recently dead mountain pine (Pinus mugo subsp. uncinata trees (n=172) and saplings (n=192) from 42 canopy gaps were assessed for Armillaria and Annosum root rot. Heterobasidion annosum s.str. proved to be the dominant pathogen and was isolated from 49% of the trees and 64% of the saplings. Armillaria was found on 13% of the trees and 20% of the saplings. Three Armillaria species, A. borealis, A. cepistipes, and A. ostoyae, were identified. Armillaria ostoyae was the most frequent species, accounting for 72% of all Armillaria isolates. A total of 31 (74%) gaps were associated with H. annosum, and six (14%) with A. ostoyae. The remaining gaps were either associated with both pathogens (7%) or with other, unknown, factors (5%). Our findings suggest that the two pathogenic fungi, H. annosum s.str. and A. ostoyae, are the main reason for the large-scale mortality of mountain pines and the creation of canopy gaps in high elevation forests of the Swiss National Par

    Excess mortality in Glasgow: further evidence of ‘political effects’ on population health

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    Objectives: The aim of the study was to update previous analyses of ‘excess mortality’ in Glasgow (Scotland) relative to the similar postindustrial cities of Liverpool and Manchester (England). The excess is defined as mortality after adjustment for socio-economic deprivation; thus, we sought to compare changes over time in both the deprivation profiles of the cities and the levels of deprivation-adjusted mortality in Glasgow relative to the other cities. This is important not only because the original analyses are now increasingly out of date but also because since publication, important (prepandemic) changes to mortality trends have been observed across all parts of the United Kingdom. Study design and methods: Replicating as far as possible the methods of the original study, we developed a three-city deprivation index based on the creation of spatial units in Glasgow that were of similar size to those in Liverpool and Manchester (average population sizes of approximately 1600, 1500 and 1700 respectively) and an area-based measure of ‘employment deprivation’. Mortality and matching population data by age, sex and small area were obtained from national agencies for two periods: 2003–2007 (the period covered by the original study) and 2014–2018. The rates of employment deprivation for each city's small areas were calculated for both periods. Indirectly standardised mortality ratios (SMRs) were calculated for Glasgow relative to Liverpool and Manchester, standardised by age and three-city deprivation decile. For context, city-level trends in age-standardised mortality rates by year, sex and city were also calculated. Results: There was evidence of a stalling of improvement in mortality rates in all three cities from the early 2010s. After adjustment for area deprivation, all-cause mortality in Glasgow in 2014–2018 was c.12% higher than in Liverpool and Manchester for all ages (SMR 112.4, 95% CI 111.1–113.6) and c.17% higher for deaths under 65 years (SMR 117.1, 95% CI 114.5–119.7). The excess was higher for males (17% compared with 9% for deaths at all ages; 25% compared with 5% for 0–64 years) and for particular causes of death such as suicide and drug-related and alcohol-related causes. The results were broadly similar to those previously described for 2003–2007, although the excess for premature mortality was notably lower. In part, this was explained by changes in levels of employment deprivation, which had decreased to a greater degree in the English cities: this was particularly true of Manchester (a reduction of −43%, compared with −38% in Liverpool and −31% in Glasgow) where the overall population size had also increased to a much greater extent than in the other cities. Conclusions: High levels of excess mortality persist in Glasgow. With the political causes recently established – the excess is a ‘political effect’, not a ‘Glasgow effect’ – political solutions are required. Thus, previously published recommendations aimed at addressing poverty, inequality and vulnerability in the city are still highly relevant. However, given the evidence of more recent, UK-wide, political effects on mortality – widening mortality inequalities resulting from UK Government ‘austerity’ measures – additional policies at UK Government level to protect, and restore, the income of the poorest in society are also urgently needed

    Bounding the dimensions of rational cohomology groups

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    Let kk be an algebraically closed field of characteristic p>0p > 0, and let GG be a simple simply-connected algebraic group over kk that is defined and split over the prime field Fp\mathbb{F}_p. In this paper we investigate situations where the dimension of a rational cohomology group for GG can be bounded by a constant times the dimension of the coefficient module. We then demonstrate how our results can be applied to obtain effective bounds on the first cohomology of the symmetric group. We also show how, for finite Chevalley groups, our methods permit significant improvements over previous estimates for the dimensions of second cohomology groups.Comment: 13 page

    Posttraumatic epilepsy in intensive care unit–treated pediatric traumatic brain injury patients

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    Objective Posttraumatic epilepsy (PTE) is a well-described complication of traumatic brain injury (TBI). The majority of the available data regarding PTE stem from the adult population. Our aim was to identify the clinical and radiological risk factors associated with PTE in a pediatric TBI population treated in an intensive care unit (ICU). Methods We used the Finnish Intensive Care Consortium database to identify pediatric ( Results Of the 290 patients included in the study, 59 (20%) developed PTE. Median age was 15 years (interquartile range [IQR] 13-17), and 80% had an admission Glasgow Coma Scale (GCS) score Significance We showed that PTE is a common long-term complication after ICU-treated pediatric TBI. Higher age, moderate injury severity, obliterated suprasellar cisterns, seizures during ICU stay, and surgical treatment are associated with an increased risk of PTE. Further studies are needed to identify strategies to decrease the risk of PTE.Peer reviewe

    Pharmacologic Targeting of Bacterial  -Glucuronidase Alleviates Nonsteroidal Anti-Inflammatory Drug-Induced Enteropathy in Mice

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    Small intestinal mucosal injury is a frequent adverse effect caused by nonsteroidal anti-inflammatory drugs (NSAIDs). The underlying mechanisms are not completely understood, but topical (luminal) effects have been implicated. Many carboxylic acid-containing NSAIDs, including diclofenac (DCF), are metabolized to acyl glucuronides (AGs), and/or ether glucuronides after ring hydroxylation, and exported into the biliary tree. In the gut, these conjugates are cleaved by bacterial ÎČ-glucuronidase, releasing the potentially harmful aglycone. We first confirmed that DCF-AG was an excellent substrate for purified Escherichia coli ÎČ-d-glucuronidase. Using a previously characterized novel bacteria-specific ÎČ-glucuronidase inhibitor (Inhibitor-1), we then found that the enzymatic hydrolysis of DCF-AG in vitro was inhibited concentration dependently (IC50 ∌164 nM). We next hypothesized that pharmacologic inhibition of bacterial ÎČ-glucuronidase would reduce exposure of enterocytes to the aglycone and, as a result, alleviate enteropathy. C57BL/6J mice were administered an ulcerogenic dose of DCF (60 mg/kg i.p.) with or without oral pretreatment with Inhibitor-1 (10 ÎŒg per mouse, b.i.d.). Whereas DCF alone caused the formation of numerous large ulcers in the distal parts of the small intestine and increased (2-fold) the intestinal permeability to fluorescein isothiocyanate-dextran, Inhibitor-1 cotreatment significantly alleviated mucosal injury and reduced all parameters of enteropathy. Pharmacokinetic profiling of DCF plasma levels in mice revealed that Inhibitor-1 coadministration did not significantly alter the Cmax, half-life, or area under the plasma concentration versus time curve of DCF. Thus, highly selective pharmacologic targeting of luminal bacterial ÎČ-d-glucuronidase by a novel class of small-molecule inhibitors protects against DCF-induced enteropathy without altering systemic drug exposure

    Ptch2/Gas1 and Ptch1/Boc differentially regulate Hedgehog signalling in murine primordial germ cell migration.

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    Gas1 and Boc/Cdon act as co-receptors in the vertebrate Hedgehog signalling pathway, but the nature of their interaction with the primary Ptch1/2 receptors remains unclear. Here we demonstrate, using primordial germ cell migration in mouse as a developmental model, that specific hetero-complexes of Ptch2/Gas1 and Ptch1/Boc mediate the process of Smo de-repression with different kinetics, through distinct modes of Hedgehog ligand reception. Moreover, Ptch2-mediated Hedgehog signalling induces the phosphorylation of Creb and Src proteins in parallel to Gli induction, identifying a previously unknown Ptch2-specific signal pathway. We propose that although Ptch1 and Ptch2 functionally overlap in the sequestration of Smo, the spatiotemporal expression of Boc and Gas1 may determine the outcome of Hedgehog signalling through compartmentalisation and modulation of Smo-downstream signalling. Our study identifies the existence of a divergent Hedgehog signal pathway mediated by Ptch2 and provides a mechanism for differential interpretation of Hedgehog signalling in the germ cell niche

    Atypical teratoid/rhabdoid tumors (ATRTs) with SMARCA4 mutation are molecularly distinct from SMARCB1-deficient cases

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    Atypical teratoid/rhabdoid tumors (ATRTs) are very aggressive childhood malignancies of the central nervous system. The underlying genetic cause are inactivating bi-allelic mutations in SMARCB1 or (rarely) in SMARCA4. ATRT-SMARCA4 have been associated with a higher frequency of germline mutations, younger age, and an inferior prognosis in comparison to SMARCB1 mutated cases. Based on their DNA methylation profiles and transcriptomics, SMARCB1 mutated ATRTs have been divided into three distinct molecular subgroups: ATRT-TYR, ATRT-SHH, and ATRT-MYC. These subgroups differ in terms of age at diagnosis, tumor location, type of SMARCB1 alterations, and overall survival. ATRT-SMARCA4 are, however, less well understood, and it remains unknown, whether they belong to one of the described ATRT subgroups. Here, we examined 14 ATRT-SMARCA4 by global DNA methylation analyses. We show that they form a separate group segregating from SMARCB1 mutated ATRTs and from other SMARCA4-deficient tumors like small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) or SMARCA4 mutated extra-cranial malignant rhabdoid tumors. In contrast, medulloblastoma (MB) samples with heterozygous SMARCA4 mutations do not group separately, but with established MB subgroups. RNA sequencing of ATRT-SMARCA4 confirmed the clustering results based on DNA methylation profiling and displayed an absence of typical signature genes upregulated in SMARCB1 deleted ATRT. In summary, our results suggest that, in line with previous clinical observations, ATRT-SMARCA4 should be regarded as a distinct molecular subgroup

    Sexual Robots: The Social-Relational Approach and the Concept of Subjective Reference

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    In this paper we propose the notion of “subjective reference” as a conceptual tool that explains how and why human-robot sexual interactions could reframe users approach to human-human sexual interactions. First, we introduce the current debate about Sexual Robotics, situated in the wider discussion about Social Robots, stating the urgency of a regulative framework. We underline the importance of a social-relational approach, mostly concerned about Social Robots impact in human social structures. Then, we point out the absence of a precise framework conceptualizing why Social Robots, and Sexual Robots in particular, may modify users’ sociality and relationality. Within a psychological framework, we propose to consider Sexual Robots as “subjective references”, namely objects symbolically referring to human subjects: we claim that, for the user experience, every action performed upon a Sexual Robot is symbolically directed toward a human subject, including degrading and violent practices. This shifting mechanism may transfer the user relational setting from human-robot interactions to human-human interactions
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