1,045 research outputs found

    On the contribution of Aitken mode particles to cloud droplet populations at continental background areas ? a parametric sensitivity study

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    International audienceAitken mode particles are potentially an important source of cloud droplets in continental background areas. In order to find out which physico-chemical properties of Aitken mode particles are most important regarding their cloud-nucleating ability, we applied a global sensitivity method to an adiabatic air parcel model simulating the number of cloud droplets formed on Aitken mode particles, CD2. The technique propagates uncertainties in the parameters describing the properties of Aitken mode to CD2. The results show that if the Aitken mode particles do not contain molecules that are able to reduce the particle surface tension more than 30% and/or decrease the mass accommodation coefficient of water, ?, below 10?2, the chemical composition and modal properties may have roughly an equal importance at low updraft velocities characterized by maximum supersaturations CD2 exhibits largest sensitivity to the particle number concentration, followed by the particle size. Also the shape of the particle mode, characterized by the geometric standard deviation (GSD), can be as important as the mode mean size at low updraft velocities. Finally, the performed sensitivity analysis revealed also that the chemistry may dominate the total sensitivity of CD2 to the considered parameters if: 1) the value of ? varies at least one order of magnitude more than what is expected for pure water surfaces (10?2?1), or 2) the particle surface tension varies more than roughly 30% under conditions close to reaching supersaturation

    Meta-analysis of GWAS of over 16,000 individuals with autism spectrum disorder highlights a novel locus at 10q24.32 and a significant overlap with schizophrenia

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    Background: Over the past decade genome-wide association studies (GWAS) have been applied to aid in the understanding of the biology of traits. The success of this approach is governed by the underlying effect sizes carried by the true risk variants and the corresponding statistical power to observe such effects given the study design and sample size under investigation. Previous ASD GWAS have identified genome-wide significant (GWS) risk loci; however, these studies were of only of low statistical power to identify GWS loci at the lower effect sizes (odds ratio (OR) <1.15). Methods: We conducted a large-scale coordinated international collaboration to combine independent genotyping data to improve the statistical power and aid in robust discovery of GWS loci. This study uses genome-wide genotyping data from a discovery sample (7387 ASD cases and 8567 controls) followed by meta-analysis of summary statistics from two replication sets (7783 ASD cases and 11359 controls; and 1369 ASD cases and 137308 controls). Results: We observe a GWS locus at 10q24.32 that overlaps several genes including PITX3, which encodes a transcription factor identified as playing a role in neuronal differentiation and CUEDC2 previously reported to be associated with social skills in an independent population cohort. We also observe overlap with regions previously implicated in schizophrenia which was further supported by a strong genetic correlation between these disorders (Rg = 0.23; P = 9 × 10−6). We further combined these Psychiatric Genomics Consortium (PGC) ASD GWAS data with the recent PGC schizophrenia GWAS to identify additional regions which may be important in a common neurodevelopmental phenotype and identified 12 novel GWS loci. These include loci previously implicated in ASD such as FOXP1 at 3p13, ATP2B2 at 3p25.3, and a ‘neurodevelopmental hub’ on chromosome 8p11.23. Conclusions: This study is an important step in the ongoing endeavour to identify the loci which underpin the common variant signal in ASD. In addition to novel GWS loci, we have identified a significant genetic correlation with schizophrenia and association of ASD with several neurodevelopmental-related genes such as EXT1, ASTN2, MACROD2, and HDAC4

    Clinical efficacy of seasonal influenza vaccination : characteristics of two outbreaks of influenza A(H1N1) in immunocompromised patients

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    Background: Influenza A(H1N1) causes serious complications in immunocompromised patients. The efficacy of seasonal vaccination in these patients has been questioned. Aim: To describe two outbreaks of influenza A(H1N1) in immunocompromised patients. Methods: Two outbreaks of influenza A(H1N1) occurred in our institution: on the kidney transplant ward in 2014 including patients early after kidney or simultaneous pancreas-kidney transplantation, and on the oncology ward in 2016 including patients receiving chemotherapy for malignant tumours. Factors leading to these outbreaks and the clinical efficacy of seasonal influenza vaccination were analysed. Findings: Altogether 86 patients were exposed to influenza A(H1N1) during the outbreaks, among whom the seasonal influenza vaccination status was unknown in 10. Only three out of 38 vaccinated patients were infected with influenza A(H1N1), compared with 20 out of 38 unvaccinated patients (P = 0.02). The death of one out of 38 vaccinated patients was associated with influenza, compared with seven out of 38 unvaccinated patients (P = 0.06). Shared factors behind the two outbreaks included outdated facilities not designed for the treatment of immunosuppressed patients. Vaccination coverage among patients was low, between 40% and 70% despite vaccination being offered to all patients free of charge. Vaccination coverage of healthcare workers on the transplant ward was low (46%), but, despite high coverage on the oncology ward (92%), the outbreak occurred. Conclusion: Seasonal influenza vaccination was clinically effective with both a reduced risk of influenza infection and a trend towards reduced mortality in these immunocompromised patients. Several possible causes were identified behind these two outbreaks, requiring continuous awareness in healthcare professionals to prevent further outbreaks. (C) 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.Peer reviewe

    Kalajoen paloapuyhdistyksen alkuvuodet 1860–1870:paloapuyhdistykset 1800-luvun lopun suomalaisen yhteiskunnan sosiaalisen rakenteen ja yhteisvastuun ilmentäjinä

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    Tiivistelmä. Kandidaatintutkielmani aihe on Pohjois-Pohjanmaan varhaisimman paloapuyhdistyksen eli Kalajoen paloapuyhdistyksen alkuvaiheet vuosien 1860–1870 välillä, sekä niiden tarkastelu yhteisvastuun käsitteen kautta. Tutkielma käsittelee syitä ja tarvetta paloapuyhdistysten perustamiselle 1800-luvun lopun Suomessa Kalajoen paloapuyhdistystä esimerkkitapauksena käyttäen. Yhteisvastuun käsitteen näkökulman valitsin, koska paloapuyhdistykset ja niitä seuranneet vakuutusyhdistykset ja -yhtiöt ovat vaikuttaneet yhteiskuntaan myös sosiaalisessa mielessä. Tutkimuskysymykset ovat seuraavat: milloin ja miksi perustettiin Pohjois-Pohjanmaan ensimmäinen paloapuyhdistys? Millaiset olivat kyseisen yhdistyksen alkuvaiheet? Lähdeaineistona tutkimuksessa ovat LähiTapiola Pohjoisen arkistoissa Oulussa ja Kalajoella sijaitsevat aineistot. Kalajoen toimipisteen arkiston aineistoista osa on irrallisia kirjeitä tai kirkossa julkisesti seurakunnalle luettuja kuulutuksia, osa taas tilikirjoja ja kokousten pöytäkirjoja. Tutkimuskirjallisuus koostuu sekä historiatieteellisistä että populaarihistorian teoksista, sillä kattavaa aiempaa tutkimusta ei aiheesta ole tehty

    Growth of sulphuric acid nanoparticles under wet and dry conditions

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    New particle formation, which greatly influences the number concentrations and size distributions of an atmospheric aerosol, is often followed by a rapid growth of freshly formed particles. The initial growth of newly formed aerosol is the crucial process determining the fraction of nucleated particles growing to cloud condensation nuclei sizes, which have a significant influence on climate. In this study, we report the laboratory observations of the growth of nanoparticles produced by nucleation of H<sub>2</sub>SO<sub>4</sub> and water in a laminar flow tube at temperatures of 283, 293 and 303 K, under dry (a relative humidity of 1%) and wet conditions (relative humidity of 30%) and residence times of 30, 45, 60 and 90 s. The initial H<sub>2</sub>SO<sub>4</sub> concentration spans the range from 2 × 10<sup>8</sup> to 1.4 × 10<sup>10</sup> molecule cm<sup>−3</sup> and the calculated wall losses of H<sub>2</sub>SO<sub>4</sub> were assumed to be diffusion limited. The detected particle number concentrations, measured by the Ultrafine Condensation Particle Counter (UCPC) and Differential Mobility Particle Sizer (DMPS), were found to depend strongly on the residence time. Hygroscopic particle growth, presented by growth factors, was found to be in good agreement with the previously reported studies. The experimental growth rates ranged from 20 nm h<sup>−1</sup> to 890 nm h<sup>−1</sup> at relative humidity (RH) 1% and from 7 nm h<sup>−1</sup> to 980 nm h<sup>−1</sup> at RH 30% and were found to increase significantly with the increasing concentration of H<sub>2</sub>SO<sub>4</sub>. Increases in the nucleation temperature had a slight enhancing effect on the growth rates under dry conditions. The influence of relative humidity on growth was not consistent – at lower H<sub>2</sub>SO<sub>4</sub> concentrations, the growth rates were higher under dry conditions while at H<sub>2</sub>SO<sub>4</sub> concentrations greater than 1 × 10<sup>10</sup> molecule cm<sup>−3</sup>, the growth rates were higher under wet conditions. The growth rates show only a weak dependence on the residence time. The experimental observations were compared with predictions made using a numerical model, which investigates the growth of particles with three different extents of neutralization by ammonia, NH<sub>3</sub>: (1) pure H<sub>2</sub>SO<sub>4</sub> – H<sub>2</sub>O particles; (2) particles formed by ammonium bisulphate, (NH<sub>4</sub>)HSO<sub>4</sub>; (3) particles formed by ammonium sulphate, (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub>. The highest growth rates were found for ammonium sulphate particles. Since the model accounting for the initial H<sub>2</sub>SO<sub>4</sub> concentration predicted the experimental growth rates correctly, our results suggest that the commonly presumed diffusional wall losses of H<sub>2</sub>SO<sub>4</sub> in case of long-lasting experiments are not so significant. We therefore assume that there are not only losses of H<sub>2</sub>SO<sub>4</sub> on the wall, but also a flux of H<sub>2</sub>SO<sub>4</sub> molecules from the wall into the flow tube, the effect being more profound under dry conditions and at higher temperatures of the tube wall. Based on a comparison with the atmospheric observations, our results indicate that sulphuric acid alone cannot explain the growth rates of particles formed in the atmosphere

    Remarks on the Central Limit Theorem for Non-Convex Bodies

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    In this note, we study possible extensions of the Central Limit Theorem for non-convex bodies. First, we prove a Berry-Esseen type theorem for a certain class of unconditional bodies that are not necessarily convex. Then, we consider a widely-known class of non-convex bodies, the so-called p-convex bodies, and construct a counter-example for this class

    Routine wastewater-based monitoring of antibiotic resistance in two Finnish hospitals : focus on carbapenem resistance genes and genes associated with bacteria causing hospital-acquired infections

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    Background: Wastewater-based monitoring represents a useful tool for antibiotic resist-ance surveillance. Aim: To investigate the prevalence and abundance of antibiotic resistance genes (ARGs) in hospital wastewater over time. Methods: Wastewater from two hospitals in Finland (HUS1 and HUS2) was monitored weekly for nine weeks (weeks 25-33) in summer 2020. A high-throughput real-time poly-merization chain reaction (HT-qPCR) system was used to detect and quantify 216 ARGs and genes associated with mobile genetic elements (MGEs), integrons, and bacteria causing hospital-acquired infections (HAIs), as well as the 16S rRNA gene. Data from HT-qPCR were analysed and visualized using a novel digital platform, ResistApp. Eight carbapenem resistance genes (blaGES, blaKPC, blaVIM, blaNDM, blaCMY, blaMOX, blaOXA48, and blaOXA51) and three genes associated with bacteria causing HAIs (Acinetobacter bau-mannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa) were studied. Findings: There was a significantly higher number of ARGs at both hospitals in weeks 27-30 (174-191 genes) compared to other sampling weeks (151-171 genes). Our analyses also indicated that the two hospitals, which used different amounts of antibiotics, had significantly different resistance gene profiles. Carbapenem resistance genes were more prevalent and abundant in HUS1 than HUS2. Across both hospitals, blaGES and blaVIM were the most prevalent and abundant. There was also a strong positive association between blaKPC and K. pneumoniae in HUS1 wastewater. Conclusion: Routine wastewater-based monitoring using ResistApp can provide valuable information on the prevalence and abundance of ARGs in hospitals. This helps hospitals understand the spread of antibiotic resistance in hospitals and identify potential areas for intervention. (c) 2021 The Authors. Published by Elsevier Ltd on behalf of The Healthcare Infection Society. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Peer reviewe

    The fate of aspergilloma patients after surgical treatment-experience from 22 cases

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    Background: Patients with pulmonary aspergillomas occasionally undergo surgery but it is somewhat unclear who of these patients benefit from surgical treatment. Methods: We retrospectively evaluated all 22 patients that underwent surgery in Helsinki University Central Hospital between 2004 and 2017. We assessed their clinical backgrounds, anti-fungal medication, indication for surgery, complications, recurrent infections and survival. Results: Of the 22 patients, 14 male and 8 female, mean age 56, an underlying pulmonary disease was present in 20. On immunosuppressive medication were 8 (36%). Most received anti-fungal medication preoperatively (n=12) and/or postoperatively (n=17), 3 patients did not receive anti-fungal medication. Length of the medication periods were diverse. Main indication for surgery was haemoptysis. One in-hospital-death occurred, and other complications included prolonged air-leak, postoperative pneumonia, pneumothorax and pneumomediastinum. No Aspergillus empyema or pleurites occurred. Five-year survival was 54%. One in-hospital-death and one other death were the result of Aspergillus disease, other deaths were unrelated to Aspergillus. Recurrent disease occurred in four cases. Three of these patients were asthma patients with allergic bronchopulmonary aspergillosis (ABPA). Conclusions: Overall results of surgery in this cohort were good and number of complications was low. Therapy with antifungals was diverse. Surgical treatment of aspergilloma can be life-saving for patients suffering of haemoptysis, and patients with restricted disease and well-preserved pulmonary capacity may benefit from surgery. Careful patient selection is crucial.Peer reviewe

    Clinical use of fungal PCR from deep tissue samples in the diagnosis of invasive fungal diseases : a retrospective observational study

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    Objectives: To assess the clinical use of panfungal PCR for diagnosis of invasive fungal diseases (IFDs). We focused on the deep tissue samples. Methods: We first described the design of panfungal PCR, which is in clinical use at Helsinki University Hospital. Next we retrospectively evaluated the results of 307 fungal PCR tests performed from 2013 to 2015. Samples were taken from normally sterile tissues and fluids. The patient population was nonselected. We classified the likelihood of IFD according to the criteria of the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG), comparing the fungal PCR results to the likelihood of IFD along with culture and microscopy results. Results: There were 48 positive (16%) and 259 negative (84%) PCR results. The sensitivity and specificity of PCR for diagnosing IFDs were 60.5% and 91.7%, respectively, while the negative predictive value and positive predictive value were 93.4% and 54.2%, respectively. The concordance between the PCR and the culture results was 86% and 87% between PCR and microscopy, respectively. Of the 48 patients with positive PCR results, 23 had a proven or probable IFD. Conclusions: Fungal PCR can be useful for diagnosing IFDs in deep tissue samples. It is beneficial to combine fungal PCR with culture and microscopy. M. Ala-Houhala, Clin Microbiol Infect 2018;24:301 (C) 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.Peer reviewe

    New determinations of gamma-ray line intensities of the Ep = 550 keV and Ep = 1747 keV resonances of the 13-C(p,gamma)14-N reaction

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    Gamma-ray angular distributions for the resonances at Ep = 550 keV and 1747 keV of the radiative capture reaction 13-C(p,g)14-N have been measured, using intense proton beams on isotopically pure 13-C targets. Relative intensities for the strongest transitions were extracted with an accuracy of typically five per cent, making these resonances new useful gamma-ray standards for efficiency calibration in the energy range Egamma = 1.6 to 9 MeV.Comment: 17 pages, 6 figures, Nuclear Instruments and Methods, Sec. A, accepte
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