530 research outputs found

    Activity of perch, Perca fluviatilis L. in relation to water temperature [Translation from: Kalamies 1973(6) 4.]

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    Catchability and activity of Perca fluviatilis in relation to temperature is examined. The number of fish caught and water temperature during the 3 summer months was used the assess the numbers of hours of activity of perch. Parallel to the research on activity, large-scale marking was carried out to establish the periods of growth during the year

    The effect of microstructure on mechanical properties of HVOF sprayed WC-CoCr composite coatings

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    This study aims for deeper understanding of the composition and phase changes occurring during HVOF spraying of the powder to WC-CoCr coatings. Also, the effect of lamellar microstructure on the mechanical properties is studied. Compositional and microstructural features are studied by means of X-ray diffraction, XRF, FE-SEM and TEM (EDX, EELS). Mechanical properties are mainly studied by different instrumented indentation and nanoindentation techniques. The use of two new fracture parameters, complementing the fracture toughness value of the coating, are proposed and examined. Higher load range indentations are used to measure cross-sectional and surface hardness, elastic modulus and fracture toughness of the coatings. Mechanical properties of individual phases are studied by nanoindentation. To our knowledge this is the first time that the mechanical properties of this amorphous/nanocrystalline matrix are studied. ICP (In-situ Coating Property) sensor, developed for quality control and residual stress evaluation, is also used to measure the elastic modulus and coefficient of thermal expansion (CTE) of the coatings. Abrasion wear resistance of the coatings are studied according to standard ASTM G 65D. Because of the brittle nature of HVOF coatings, the main focus of this study is in the effects of coating microstructure on fracture toughness, and on crack initiation and propagation resistance. It is shown that even when two similar coatings have equal indentation fracture toughness values, the critical crack initiation loads may be very different. This new parameter is expected to be extremely useful in the evaluation of the coating performance under loading conditions

    Clinical and microbiological characterization of Aerococcus urinae bacteraemias at Helsinki metropolitan area, Finland

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    Our objective was to assess the incidence of bacteraemic Aerococcus urinae cases at Helsinki metropolitan area, Finland, from a 6-year study period (2013 to 2018) and to further characterize available cases. The study evaluates the outcome of commonly used cefuroxime treatment and determinate a set of A. urinae in vitro antimicrobial susceptibilities for benzylpenicillin, cefuroxime, and ceftriaxone. Clinical records of A. urinae bacteraemic patients were reviewed retrospectively. Antimicrobial susceptibility testing was performed by disk diffusion, gradient test, and broth microdilution for 139-141 clinical A. urinae isolates. Clinical data of 72/77 patients were combined with the in vitro susceptibilities. We found an increasing number of bacteraemic A. urinae cases within 6-year study period (p = 0.01). The patients were mainly elderly males, and all suffered from underlying conditions. A total of 27.3% of cases (21/77) showed polymicrobial blood cultures. Thirty-day mortality was 22.1%. Cefuroxime was the initial empiric antimicrobial agent given for 66/76 of the patients and treatment outcome was favorable for 20/22 patients who received cefuroxime at least up to day 5. All isolates were susceptible to benzylpenicillin and cefuroxime interpreted by EUCAST breakpoints for Aerococci and PK-PD breakpoints, respectively. MIC determinations gave variable results for ceftriaxone, 2.1-2.9% of the isolates were resistant. To conclude, it seems that the number of bacteraemic Aerococcus urinae cases is increasing at Helsinki metropolitan area, Finland, reflecting the growing blood culture sampling. Clinical A. urinae isolates were susceptible to cefuroxime in vitro. Treatment data indicate that empirical cefuroxime started for possibly urinary tract -derived community-acquired bacteraemia covers A. urinae.Peer reviewe

    Two is more valid than one, but is six even better? The factor structure of the Self-Compassion Scale (SCS)

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    IntroductionSelf-compassion refers to a non-evaluative, interconnected and mindful attitude towards oneself especially when facing difficulties or feelings of personal inadequacies. The Self-Compassion Scale (SCS) is a frequently used instrument designed to measure self-compassion either by using the six subscale scores, or by calculating a total score, averaged across all 26 items. PurposeThe purpose of this study is to examine the factor structure of the Self-Compassion Scale, and in particular, whether the widely used six-factor model and the unidimensional model can be confirmed. MethodsThe internal structure of the SCS was examined using confirmatory factor analysis (CFA). Six different models (a one-factor model, an oblique six-factor model, a higher-order model, an oblique two-factor model, a bi-factor model with one general factor (bifactor model) and a bi-factor model with two general factors, i.e. two-bifactor model) were tested in a sample of adolescents (n = 1725; 50.3% female; mean age = 16.56, SD = 1.95). All models were replicated using responses collected five months after the first data collection from 1497 students (W2), who were largely, but not completely, the same students involved in W1 data collection. ResultsFit indices for the two-factor model implied an acceptable fit, but none of the remaining models tested met the criteria for an adequate solution. Although the fit indices for the six-factor model suggested an acceptable fit to the data, in this model the negative components of the SCS were highly correlated with each other, especially with the over-identification factor. ConclusionThe results of this study provide evidence to support the use of the separate self-compassion- and self-coldness -scores rather than the overall score of the SCS. Although the fit indices supported the six-factor model, the use of six subscale scores cannot be recommended on the basis of our results given the extremely high correlations within this model between some factors.</div

    Stapled truncated orexin peptides as orexin receptor agonists

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    The peptides orexin-A and -B, the endogenous agonists of the orexin receptors, have similar 19-amino-acid C-termini which retain full maximum response as truncated peptides with only marginally reduced potency, while further N-terminal truncations successively reduce the activity. The peptides have been suggested to bind in an α‐helical conformation, and truncation beyond a certain critical length is likely to disrupt the overall helical structure. In this study, we set out to stabilize the α‐helical conformation of orexin‐A15–33 via peptide stapling at four different sites. At a suggested hinge region, we varied the length of the cross-linker as well as replaced the staple with two α-aminoisobutyric acid residues. Modifications close to the peptide C‐terminus, which is crucial for activity, were not allowed. However, central and N‐terminal modifications yielded bioactive peptides, albeit with decreased potencies. This provides evidence that the orexin receptors can accommodate and be activated by α-helical peptides. The decrease in potency is likely linked to a stabilization of suboptimal peptide conformation or blocking of peptide backbone–receptor interactions at the hinge region by the helical stabilization or the modified amino acids.Peer reviewe

    COVID-19 outbreak at a reception centre for asylum seekers in Espoo, Finland

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    Publisher Copyright: © 2021Background shared accommodation may increase the risk of SARS-CoV-2 transmission. In April 2020, an increasing number of asylum seekers at a reception centre in Espoo, Finland presented with COVID-19 despite earlier implementation of preventive measures. We decided to screen the entire population of the centre for SARS-CoV-2. Methods we offered nasopharyngeal swab collection and SARS-CoV-2 real-time polymerase chain reaction (RT-PCR) analysis to the centre's clients. Symptoms were recorded at the time of diagnostic sample collection using electronic forms and followed up for two weeks through phone interviews and a review of medical records. Findings 260 clients were screened. Of them, 96 (37%) were found positive for SARS-CoV-2 and isolated. The high attack rate prompted the local public health authority to set the other clients in quarantine for 14 days to prevent further spread. Of the positive cases, 61 (64%) reported having had symptoms at the time of the screening or one week prior. Of the 35 initially asymptomatic individuals, 12 developed symptoms during follow-up, while 23 (or 18% of all screened SARS-CoV-2 positive clients) remained asymptomatic. No widespread transmission of COVID-19 was detected after the quarantine was lifted. Interpretation in this large COVID-19 outbreak, voluntary mass screening provided valuable information about its extent and helped guide the public health response. Comprehensive quarantine and isolation measures were likely instrumental in containing the outbreak. Funding Finnish Institution for Health and Welfare, Finnish Immigration Agency, City of EspooPeer reviewe

    Energetic electron precipitation associated with pulsating aurora: EISCAT and Van Allen Probe observations

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    Pulsating auroras show quasi-periodic intensity modulations caused by the precipitation of energetic electrons of the order of tens of keV. It is expected theoretically that not only these electrons but also sub-relativistic/relativistic electrons precipitate simultaneously into the ionosphere owing to whistler-mode wave–particle interactions. The height-resolved electron density profile was observed with the European Incoherent Scatter (EISCAT) Tromsþ VHF radar on 17 November 2012. Electron density enhancements were clearly identified at altitudes >68 km in association with the pulsating aurora, suggesting precipitation of electrons with a broadband energy range from ~10 keV up to at least 200 keV. The riometer and network of subionospheric radio wave observations also showed the energetic electron precipitations during this period. During this period, the footprint of the Van Allen Probe-A satellite was very close to Tromsþ and the satellite observed rising tone emissions of the lower-band chorus (LBC) waves near the equatorial plane. Considering the observed LBC waves and electrons, we conducted a computer simulation of the wave–particle interactions. This showed simultaneous precipitation of electrons at both tens of keV and a few hundred keV, which is consistent with the energy spectrum estimated by the inversion method using the EISCAT observations. This result revealed that electrons with a wide energy range simultaneously precipitate into the ionosphere in association with the pulsating aurora, providing the evidence that pulsating auroras are caused by whistler chorus waves. We suggest that scattering by propagating whistler simultaneously causes both the precipitations of sub-relativistic electrons and the pulsating aurora

    Parameterisation of the chemical effects of sprites in the middle atmosphere

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    Transient luminous events, such as red sprites, occur in the middle atmosphere in the electric field above thunderstorms. We here address the question whether these processes may be a significant source of odd nitrogen and affect ozone or other important trace species. A well-established coupled ion-neutral chemical model has been extended for this purpose and applied together with estimated rates of ionisation, excitation and dissociation based on spectroscopic ratios from ISUAL on FORMOSAT-2. This approach is used to estimate the NO&lt;sub&gt;x&lt;/sub&gt; and ozone changes for two type cases. &lt;br&gt;&lt;br&gt; The NO&lt;sub&gt;x&lt;/sub&gt; enhancements are at most one order of magnitude in the streamers, which means a production of at most 10 mol per event, or (given a global rate of occurrence of three events per minute) some 150&amp;ndash;1500 kg per day. The present study therefore indicates that sprites are insignificant as a global source of NO&lt;sub&gt;x&lt;/sub&gt;. Local effects on ozone are also negligible, but the local enhancement of NO&lt;sub&gt;x&lt;/sub&gt; may be significant, up to 5 times the minimum background at 70 km in extraordinary cases
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