527 research outputs found

    Increased Expression of Simple Ganglioside Species GM2 and GM3 Detected by MALDI Imaging Mass Spectrometry in a Combined Rat Model of A beta Toxicity and Stroke

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    The aging brain is often characterized by the presence of multiple comorbidities resulting in synergistic damaging effects in the brain as demonstrated through the interaction of Alzheimer\u27s disease (AD) and stroke. Gangliosides, a family of membrane lipids enriched in the central nervous system, may have a mechanistic role in mediating the brain\u27s response to injury as their expression is altered in a number of disease and injury states. Matrix-Assisted Laser Desorption Ionization (MALDI) Imaging Mass Spectrometry (IMS) was used to study the expression of A-series ganglioside species GD1a, GM1, GM2, and GM3 to determine alteration of their expression profiles in the presence of beta-amyloid (A beta) toxicity in addition to ischemic injury. To model a stroke, rats received a unilateral striatal injection of endothelin-1 (ET-1) (stroke alone group). To model A beta toxicity, rats received intracerebralventricular (icv) injections of the toxic 25-35 fragment of the A beta peptide (A beta alone group). To model the combination of A beta toxicity with stroke, rats received both the unilateral ET-1 injection and the bilateral icv injections of A beta(25-35) (combined A beta/ET-1 group). By 3 d, a significant increase in the simple ganglioside species GM2 was observed in the ischemic brain region of rats who received a stroke (ET-1), with or without A beta. By 21 d, GM2 levels only remained elevated in the combined A beta/ET-1 group. GM3 levels however demonstrated a different pattern of expression. By 3 d GM3 was elevated in the ischemic brain region only in the combined A beta/ET-1 group. By 21 d, GM3 was elevated in the ischemic brain region in both stroke alone and A beta/ET-1 groups. Overall, results indicate that the accumulation of simple ganglioside species GM2 and GM3 may be indicative of a mechanism of interaction between AD and stroke

    Temperature dependence in interatomic potentials and an improved potential for Ti

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    The process of deriving an interatomic potentials represents an attempt to integrate out the electronic degrees of freedom from the full quantum description of a condensed matter system. In practice it is the derivatives of the interatomic potentials which are used in molecular dynamics, as a model for the forces on a system. These forces should be the derivative of the free energy of the electronic system, which includes contributions from the entropy of the electronic states. This free energy is weakly temperature dependent, and although this can be safely neglected in many cases there are some systems where the electronic entropy plays a significant role. Here a method is proposed to incorporate electronic entropy in the Sommerfeld approximation into empirical potentials. The method is applied as a correction to an existing potential for titanium. Thermal properties of the new model are calculated, and a simple method for fixing the melting point and solid-solid phase transition temperature for existing models fitted to zero temperature data is presented.Comment: CCP 201

    The Parkes Observatory Pulsar Data Archive

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    The Parkes pulsar data archive currently provides access to 144044 data files obtained from observations carried out at the Parkes observatory since the year 1991. Around 10^5 files are from surveys of the sky, the remainder are observations of 775 individual pulsars and their corresponding calibration signals. Survey observations are included from the Parkes 70cm and the Swinburne Intermediate Latitude surveys. Individual pulsar observations are included from young pulsar timing projects, the Parkes Pulsar Timing Array and from the PULSE@Parkes outreach program. The data files and access methods are compatible with Virtual Observatory protocols. This paper describes the data currently stored in the archive and presents ways in which these data can be searched and downloaded.Comment: Accepted by PAS

    A randomised feasibility trial comparing needle fasciotomy with limited fasciectomy treatment for Dupuytren’s contractures

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    © 2020 The Author(s). Purpose: The purpose of this study is to assess the feasibility of conducting a large, multicentre randomised controlled trial (RCT) comparing needle fasciotomy with limited fasciectomy for treatment of Dupuytren's contractures. Design: The design of this study is a parallel, two-arm, multicentre, randomised feasibility trial with embedded QuinteT Recruitment Intervention. Participants: Patients aged 18 years or over who were referred from primary to secondary care for treatment of a hand with Dupuytren's contractures of one or more fingers of more than 30° at the metacarpophalangeal (MCP) and/or proximal interphalangeal (PIP) joints and well-defined cord(s). Patients were excluded if they had undergone previous Dupuytren's contracture surgery on the same hand. Methods: Potential participants were screened for eligibility. Recruited participants randomised (1:1) to treatment with either needle fasciotomy or limited fasciectomy and followed-up for up to 6 months after treatment. Data on recruitment rates, completion of follow-up, and procedure costs were collected. Four patient reported outcome measures (PROMs) and objective outcome measures were collected before intervention and 6 weeks and 6 months afterwards. Results: One hundred and fifty-three of 267 (57%) primary-care referrals for Dupuytren's contractures met the eligibility criteria for the study. Seventy-one of the 153 (46%) agreed to participate and were randomly allocated to treatment with needle fasciotomy or limited fasciectomy. Sixty-seven of these underwent their allocated treatment, two were crossovers from limited fasciectomy to needle fasciotomy, and two (both allocated limited fasciectomy) received no treatment. Fifty-nine participants (85%) completed 6-month follow-up PROMs. Participants felt the MYMOP, PEM and URAM PROMs allowed them to better describe how their treatment affected their hand function than the DASH PROM. The estimated costs of limited fasciectomy (in an operating theatre) and needle fasciotomy (in a clinic room) were £777 and £111 respectively. Conclusion: A large RCT comparing treatment of Dupuytren's contractures by needle fasciotomy and limited fasciectomy is feasible. Data from this study will help determine the number of sites and duration of recruitment required to complete an adequately powered RCT and will assist the selection of PROMs in future studies on the treatment of Dupuytren's contractures. (Level 1 feasibility study)

    Valtion aluehallintovirastot ja niiden ylijohtajat: Pohjoiseurooppalainen analogia Ranskan prefeikteille

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    This chapter examines the closest Finnish analogy to the French function of the prefect. In Finland, since 2010, this function has been vested in the institution of the State Regional Administrative Agency (SRAA, aluehallintovirasto, ‘AVI’). There are six SRAAs, each headed by a Chief Director (ylijohtaja) nominated by the government. The study had four main findings. First, despite ambiguity in institutional terminology, classifications, boundaries and identities concerning the SRAA, one can discern few true functional or structural deficiencies. Second, the SRAA is a hybrid between an institution of its own and a territorial representative of either government ministries or government agencies, to which is related the fact that each SRAA has both responsibilities concerning its territory and nationwide responsibilities. Third, tensions between performance and institutional legitimation prevail in the institution of the SRAA, but again without serious deficiencies. Fourth, the 2010 substitution of the SRAA for the former Province comprised a radical institutional change. The 2015–2019 Finnish government intended to abolish the SRAAs, but the subsequent government abandoned that reform, and ultimately by mid-2020 it became clear that the institution of the SRAA was here to stay after all.Peer reviewe

    Measurement of the rate of nu_e + d --> p + p + e^- interactions produced by 8B solar neutrinos at the Sudbury Neutrino Observatory

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    Solar neutrinos from the decay of 8^8B have been detected at the Sudbury Neutrino Observatory (SNO) via the charged current (CC) reaction on deuterium and by the elastic scattering (ES) of electrons. The CC reaction is sensitive exclusively to nu_e's, while the ES reaction also has a small sensitivity to nu_mu's and nu_tau's. The flux of nu_e's from ^8B decay measured by the CC reaction rate is \phi^CC(nu_e) = 1.75 +/- 0.07 (stat)+0.12/-0.11 (sys.) +/- 0.05(theor) x 10^6 /cm^2 s. Assuming no flavor transformation, the flux inferred from the ES reaction rate is \phi^ES(nu_x) = 2.39+/-0.34 (stat.)+0.16}/-0.14 (sys) x 10^6 /cm^2 s. Comparison of \phi^CC(nu_e) to the Super-Kamiokande Collaboration's precision value of \phi^ES(\nu_x) yields a 3.3 sigma difference, providing evidence that there is a non-electron flavor active neutrino component in the solar flux. The total flux of active ^8B neutrinos is thus determined to be 5.44 +/-0.99 x 10^6/cm^2 s, in close agreement with the predictions of solar models.Comment: 6 pages (LaTex), 3 figures, submitted to Phys. Rev. Letter

    Responses of marine benthic microalgae to elevated CO<inf>2</inf>

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    Increasing anthropogenic CO2 emissions to the atmosphere are causing a rise in pCO2 concentrations in the ocean surface and lowering pH. To predict the effects of these changes, we need to improve our understanding of the responses of marine primary producers since these drive biogeochemical cycles and profoundly affect the structure and function of benthic habitats. The effects of increasing CO2 levels on the colonisation of artificial substrata by microalgal assemblages (periphyton) were examined across a CO2 gradient off the volcanic island of Vulcano (NE Sicily). We show that periphyton communities altered significantly as CO2 concentrations increased. CO2 enrichment caused significant increases in chlorophyll a concentrations and in diatom abundance although we did not detect any changes in cyanobacteria. SEM analysis revealed major shifts in diatom assemblage composition as CO2 levels increased. The responses of benthic microalgae to rising anthropogenic CO2 emissions are likely to have significant ecological ramifications for coastal systems. © 2011 Springer-Verlag

    First Neutrino Observations from the Sudbury Neutrino Observatory

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    The first neutrino observations from the Sudbury Neutrino Observatory are presented from preliminary analyses. Based on energy, direction and location, the data in the region of interest appear to be dominated by 8B solar neutrinos, detected by the charged current reaction on deuterium and elastic scattering from electrons, with very little background. Measurements of radioactive backgrounds indicate that the measurement of all active neutrino types via the neutral current reaction on deuterium will be possible with small systematic uncertainties. Quantitative results for the fluxes observed with these reactions will be provided when further calibrations have been completed.Comment: Latex, 7 pages, 10 figures, Invited paper at Neutrino 2000 Conference, Sudbury, Canada, June 16-21, 2000 to be published in the Proceeding

    The accuracy of the report of hepatic steatosis on ultrasonography in patients infected with hepatitis C in a clinical setting: A retrospective observational study

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    BACKGROUND: Steatosis is occasionally reported during screening ultrasonography in patients with hepatitis C virus (HCV). We conducted a retrospective observational study to assess the factors associated with steatosis on ultrasonography and the relationship between steatosis on ultrasound versus biopsy in patients infected with HCV in a clinical setting. Our hypothesis was ultrasonography would perform poorly for the detection of steatosis outside of the context of a controlled study, primarily due to false-positive results caused by hepatic fibrosis and inflammation. METHODS: A retrospective review of ultrasound reports was conducted on patients infected with HCV in a tertiary care gastroenterology clinic. Reports were reviewed for the specific documentation of the presence of steatosis. Baseline clinical and histologic parameters were recorded, and compared for patients with vs. without steatosis. Multiple logistic regression analysis was performed on these baseline variables. Liver biopsies were reviewed by two pathologists, and graded for steatosis. Steatosis on biopsy was compared to steatosis on ultrasound report, and the performance characteristics of ultrasonography were calculated, using biopsy as the gold standard. RESULTS: Ultrasound reports were available on 164 patients. Patients with steatosis on ultrasound had a higher incidence of the following parameters compared to patients without steatosis: diabetes (12/49 [24%] vs. 7/115 [6%], p < 0.001), fibrosis stage >2 (15/48 [31%] vs. 16/110 [15%], p = 0.02), histologic grade >2 (19/48 [40%] vs. 17/103 [17%], p = 0.002), and ALT (129.5 ± 89.0 IU/L vs. 94.3 ± 87.0 IU/L, p = 0.01). Histologic grade was the only factor independently associated with steatosis with multivariate analysis. When compared to the histologic diagnosis of steatosis (n = 122), ultrasonography had a substantial number of false-positive and false-negative results. In patients with a normal ultrasound, 8/82 (10%) had >30% steatosis on biopsy. Among patients with steatosis reported on ultrasound, only 12/40 (30%) had >30% steatosis on biopsy review. CONCLUSION: Steatosis on ultrasound is associated with markers of inflammation and fibrosis in HCV-infected patients, but does not consistently correlate with steatosis on biopsy outside of the context of a controlled study. Clinicians should be skeptical of the definitive diagnosis of steatosis on hepatic ultrasonography
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