437 research outputs found
Elektrokemijsko ispitivanje stabilnosti pasivnog stanja i korozijske otpornosti supermartenzitnog nehrđajućeg čelika
On low interstitial - supermartensitic stainless steels (X1CrNiMo 12-5-1, X2CrNiMo 13-6-2, X1CrNiMo 12-6-2) the electrochemical potentiodynamic polarization tests were carried out and the passive state stability and localized corrosion resistance were compared and evaluated. The effect of quenching and tempering as well as the changes in microstructure on polarisation curves and corrosion properties at room temperature were established. Small differences in chemical composition of steels were also registered on their corrosion parameters changes and resistance.Rad prikazuje usporedbu i procjenu stabilnosti pasivnog stanja i lokalnu otpornost koroziji temeljem ispitivanja elektrokemijske potenciodinamičke polarizacije nisko-intersticijskih supermartenzitnih nehrđajućih čelika (X1CrNiMo 12-5-1, X2CrNiMo 13-6-2, X1CrNiMo 12-6-2). Utvrđeni su utjecaj poboljšavanja čelika i mikrostrukturne promjene na polarizacijskim krivuljama uzoraka te korozijska svojstva pri sobnoj temperaturi. Uočena je i povezanost malih odstupanja kemijskog sastava čelika s promjenom korozijskih parametera i korozijskom otpornošću
Trends in the Electrochemical Polarization Potentiodynamic Reactivation Method – EPR
This method designed to examine the susceptibility to nonuniform corrosion, ranks among the more successful technique developments. One of its numerous advantages is that it allows nondestructive, on-site examination. EPR measurements are used to establish
the resistance of stainless steels and alloys to intergranular corrosion and stress corrosion cracking e.g. in nuclear engineering applications as well as to study grain boundary precipitation and other minute local changes in alloy composition and structure. By the EPR test, the specimen and/or the field object (working electrode) is tested
in acid solutions, most often in solutions of sulfuric acid (c = 0.01–5 mol dm–3 H2SO4) and potassium thiocyanate (c = 0.001 to 0.1 mol dm–3 KSCN). The principle of the measurements is to reactivate the sample from the incomplete passivity region. This indicates local changes in chemical composition in relation to phase transformations
A guide to laboratory use of the squid Loligo pealei
From the Preface: Unfortunately, a guide like this one does not happen simply. It is the product
of polite requests (at first polite, anyway) from colleagues, of mutual nagging, and
of wives with persistant memories. What we are attempting to achieve with this
contribution is a consolidation of many years of personal experience with squid
into a source of practical information hopefully useful to the increasing number of
people working with the squid. One does not undertake the task of preparing such
a guide for a limited audience with unreserved enthusiasm. It always seems the
same amount of work could produce something for a larger audience and therefore,
hopefully, of greater significance. On the other hand when the hours and days spent
on developing handling procedures, techniques, and "tricks of the squid trade" are
considered it seems untenable not to pass this otherwise unpublishable data on in
hope of saving others like pain and time. Therefore, what we have attempted to do
is informally put together information that should prove useful to people interested
in all aspects of squid biology. In this way we hope to make the laboratory utilization
of the squid more efficient not only from the standpoint of the investigator and the
collector but also for the future of the species Loligo pealei
Lmo4 in the Basolateral Complex of the Amygdala Modulates Fear Learning
Pavlovian fear conditioning is an associative learning paradigm in which mice learn to associate a neutral conditioned stimulus with an aversive unconditioned stimulus. In this study, we demonstrate a novel role for the transcriptional regulator Lmo4 in fear learning. LMO4 is predominantly expressed in pyramidal projection neurons of the basolateral complex of the amygdala (BLC). Mice heterozygous for a genetrap insertion in the Lmo4 locus (Lmo4gt/+), which express 50% less Lmo4 than their wild type (WT) counterparts display enhanced freezing to both the context and the cue in which they received the aversive stimulus. Small-hairpin RNA-mediated knockdown of Lmo4 in the BLC, but not the dentate gyrus region of the hippocampus recapitulated this enhanced conditioning phenotype, suggesting an adult- and brain region-specific role for Lmo4 in fear learning. Immunohistochemical analyses revealed an increase in the number of c-Fos positive puncta in the BLC of Lmo4gt/+ mice in comparison to their WT counterparts after fear conditioning. Lastly, we measured anxiety-like behavior in Lmo4gt/+ mice and in mice with BLC-specific downregulation of Lmo4 using the elevated plus maze, open field, and light/dark box tests. Global or BLC-specific knockdown of Lmo4 did not significantly affect anxiety-like behavior. These results suggest a selective role for LMO4 in the BLC in modulating learned but not unlearned fear
Axonal transport of calmodulin: a physiologic approach to identification of long-term associations between proteins.
EQ-5D in skin conditions: an assessment of validity and responsiveness
Aims and objectives This systematic literature review aims to assess the reliability, validity and responsiveness of three widely used generic preference-based measures of health-related quality of life (HRQL), i.e., EQ-5D, Health Utility Index 3 (HUI3) and SF-6D in patients with skin conditions. Methods A systematic search was conducted to identify studies reporting health state utility values obtained using EQ-5D, SF-6D, or HUI3 alongside other HRQL measures or clinical indices for patients with skin conditions. Data on test-retest analysis for reliability, known group differences or correlation and regression analyses for validity, and change over time or responsiveness indices analysis were extracted and reviewed. Results A total of 16 papers reporting EQ-5D utilities in people with skin conditions were included in the final review. No papers for SF-6D and HUI3 were found. Evidence of reliability was not found for any of these measures. The majority of studies included in the review (12 out of 16) examined patients with plaque psoriasis or psoriatic arthritis and the remaining four studies examined patients with either acne, hidradenitis suppurativa, hand eczema, or venous leg ulcers. The findings were generally positive in terms of performance of EQ-5D. Six studies showed that EQ-5D was able to reflect differences between severity groups and only one reported differences that were not statistically significant. Four studies found that EQ-5D detected differences between patients and the general population, and differences were statistically different for three of them. Further, moderate-to-strong correlation coefficients were found between EQ-5D and other skin-specific HRQL measures in four studies. Eight studies showed that EQ-5D was able to detect change in HRQL appropriately over time and the changes were statistically significant in seven studies. Conclusions Overall, the validity and responsiveness of the EQ-5D was found to be good in people with skin diseases, especially plaque psoriasis or psoriatic arthritis. No evidence on SF-6D and HUI3 was available to enable any judgments to be made on their performance
Molecular characterisation of protist parasites in human-habituated mountain gorillas (Gorilla beringei beringei), humans and livestock, from Bwindi impenetrable National Park, Uganda
Over 60 % of human emerging infectious diseases are zoonotic, and there is growing evidence of the zooanthroponotic transmission of diseases from humans to livestock and wildlife species, with major implications for public health, economics, and conservation. Zooanthroponoses are of relevance to critically endangered species; amongst these is the mountain gorilla (Gorilla beringei beringei) of Uganda. Here, we assess the occurrence of Cryptosporidium, Cyclospora, Giardia, and Entamoeba infecting mountain gorillas in the Bwindi Impenetrable National Park (BINP), Uganda, using molecular methods. We also assess the occurrence of these parasites in humans and livestock species living in overlapping/adjacent geographical regions
The UEFA Champions League seeding is not strategy-proof since the 2015/16 season
Fairness has several interpretations in sports, one of them being that the
rules should guarantee incentive compatibility, namely, a team cannot be worse
off due to better results in any feasible scenario. The current seeding regime
of the most prestigious annual European club football tournament, the UEFA
(Union of European Football Associations) Champions League, is shown to violate
this requirement since the 2015/16 season. In particular, if the titleholder
qualifies for the first pot by being a champion in a high-ranked league, its
slot is given to a team from a lower-ranked association, which can harm a top
club from the domestic championship of the titleholder. However, filling all
vacancies through the national leagues excludes the presence of perverse
incentives. UEFA is encouraged to introduce this policy from the 2021-24 cycle
onwards.Comment: 11 pages, 1 figure, 1 tabl
An Evolutionary Conserved Role for Anaplastic Lymphoma Kinase in Behavioral Responses to Ethanol
Anaplastic lymphoma kinase (Alk) is a gene expressed in the nervous system that encodes a receptor tyrosine kinase commonly known for its oncogenic function in various human cancers. We have determined that Alk is associated with altered behavioral responses to ethanol in the fruit fly Drosophila melanogaster, in mice, and in humans. Mutant flies containing transposon insertions in dAlk demonstrate increased resistance to the sedating effect of ethanol. Database analyses revealed that Alk expression levels in the brains of recombinant inbred mice are negatively correlated with ethanol-induced ataxia and ethanol consumption. We therefore tested Alk gene knockout mice and found that they sedate longer in response to high doses of ethanol and consume more ethanol than wild-type mice. Finally, sequencing of human ALK led to the discovery of four polymorphisms associated with a low level of response to ethanol, an intermediate phenotype that is predictive of future alcohol use disorders (AUDs). These results suggest that Alk plays an evolutionary conserved role in ethanol-related behaviors. Moreover, ALK may be a novel candidate gene conferring risk for AUDs as well as a potential target for pharmacological intervention
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