1,183 research outputs found
Thermodynamic assessment of the KF-ThF<sub>4</sub>, LiF-KF-ThF<sub>4</sub> and NaF-KF-ThF<sub>4</sub> systems
No full textA thermodynamic assessment of the KF-ThF4 binary system using the CALPHAD method is presented, where the liquid solution is described by the modified quasichemical formalism in the quadruplet approximation. The optimization of the phase diagram is based on experimental data reported in the literature and newly measured X-ray diffraction and differential scanning calorimetry data, which have allowed to solve discrepancies between past assessments. The low temperature heat capacity of α-K2ThF6 has also been measured using thermal relaxation calorimetry; from these data the heat capacity and standard entropy values have been derived at 298.15 K: Cp,mo(K2ThF6,cr,298.15K)=(193.2±3.9) J·K-1·mol-1 and Smo(K2ThF6,cr,298.15K)=(256.9±4.8) J·K-1·mol-1. Taking existing assessments of the relevant binaries, the new optimization is extrapolated to the ternary systems LiF-KF-ThF4 and NaF-KF-ThF4 using an asymmetric Kohler/Toop formalism. The standard enthalpy of formation and standard entropy of KNaThF6 are re-calculated from published e.m.f data, and included in the assessment of the ternary system. A calculated projection of the NaF-KF-ThF4 system at 300 K and the optimized liquidus projections of both systems are compared to published phase equilibrium data at room temperature and along the LiF-LiThF5 and NaF-KThF5 pseudobinaries, with good agreement.RST/Reactor Physics and Nuclear Material
Wound Assessment: Made Easy
No full textA structured approach to wound assessment is required to maintain a good standard of care. This involves a thorough patient assessment, which should be carried out by skilled and competent practitioners, adhering to local and national guidelines (Harding et al, 2008). Inappropriate or inaccurate assessment can lead to delayed wound healing, pain, increased risk of infection, inappropriate use of wound dressings and a reduction in the quality of life for patients
Húsz év után. A Könyvtári Figyelő 2000–2019 között
No full textThe study provides an overview of the life of this peer-reviewed national professional journal edited at the Hungarian Library Institute in the period 2000 through 2019. Könyvtári Figyelő entered its 65th volume this year. This quarterly magazine has published 80 issues and more than 15,000 pages in PDF format in twenty years. Thanks to the support of the National Cultural Fund (NKA) printed issues continue to be published to our days. The full text of issues can be accessed and searched on an electronic interface (http://ki.oszk.hu/kf) from the beginnings (1955) to the present day (2020/1). Roughly two-thirds of each issue include research articles on the main events and developments in Hungarian librarianship, and one-third deals with the presentation of developments in the international library world. The author reviews the most important articles in the Studies, Our past, and Book reviews columns in two ten-year cycles, and refers to the professional trends summarized at the beginning of her article. The editors are increasingly oriented towards open access and the application of the Open Journal System (OJS).A tanulmány áttekintés a Könyvtári Intézetben készülő, idén 65. évfolyamába lépett, országos hatókörű, lektorált szakmai folyóirat 2000 és 2019 közötti működéséről. A negyedéves megjelenésű folyóirat húsz év alatt 80 füzetszámban, több mint 15 ezer pdf oldal terjedelemben jelent meg. Az NKA támogatásának köszönhetően ez idáig nyomtatott formában is elkészülhetett. Elektronikus felületén (http://ki.oszk.hu/kf) a kezdetektől (1955 től) napjainkig (2020/1.) elérhető és kereshető a lapszámok teljes szövege. Minden szám nagyjából kétharmadában részben a magyarországi könyvtárügy legfőbb eseményeiről és fejlesztéseiről közöl elméleti publikációkat, egyharmadában pedig a külföldi könyvtári világ fejleményeinek bemutatásával foglalkozik. Kétszer tíz éves ciklusra bontva tekinti át a szerző a Tanulmányok, a Múltunk és a Könyvszemle rovatok legfontosabb írásait, és utal a cikkek beszámolója elején felvillantott szakmai trendekkel való kapcsolatára. A szerkesztőség számára a jövő útja a nyílt hozzáférés és az Open Journal System (OJS) nyílt forráskódú szerkesztőségi rendszer kialakítása felé vezet
Permanent draft genome sequence of Comamonas testosteroni KF-1
No full textComamonas testosteroni KF-1 is a model organism for the elucidation of the novel biochemical degradation pathways for xenobiotic 4-sulfophenylcarboxylates (SPC) formed during biodegradation of synthetic 4‑sulfophenylalkane surfactants (linear alkylbenzenesulfonates, LAS) by bacterial communities. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 6,026,527 bp long chromosome (one sequencing gap) exhibits an average G+C content of 61.79% and is predicted to encode 5,492 protein-coding genes and 114 RNA genes.publishe
Thermodynamic assessment of the LiF-NiF<sub>2</sub>, NaF-NiF<sub>2</sub> and KF-NiF<sub>2</sub> systems
No full textUsing the modified quasi-chemical model in the quadruplet approximation, three new thermodynamic assessments of binary systems useful for the detailed operational design of the Molten Salt Reactor are presented: AF-NiF2 (A = Li, Na, K). These systems are particularly relevant for the study of the molten salt-structural materials interaction, as the salt containment is made of a Ni-based alloy. Using powder X-ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC), new experimental data were gathered for two of these systems, LiF-NiF2 and KF-NiF2, and compared to previous experimental assessments. Our data have confirmed the formation of a (Li1-2xNix)F solid solution. The three thermodynamic models show a very good agreement with the experimental data. The melting point of NiF2 was measured for the first time to be T = (1629 ± 5) K, and the thermal expansion coefficient for Li2NiF4 was found to be α=27.6·10-6K-1 in the temperature range T = (298–773) K.Accepted Author ManuscriptRST/Reactor Physics and Nuclear Material
Selection bias: neighbourhood controls and controls selected from those presenting to a Health Unit in a case control study of efficacy of BCG revaccination.
No full textBACKGROUND: In most case control studies the hardest decision is the choice of the control group, as in the ideal control group the proportion exposed is the same as in the population that produced the cases. METHODS: A comparison of two control groups in a case control study of the efficacy of BCG revaccination. One group was selected from subjects presenting to the heath unit the case attended for routine prevention and care; the second group was selected from the neighbourhood of cases. All Health Units from which controls were selected offered BCG revaccination. Efficacy estimated in a randomized control trial of BCG revaccination was used to establish that the neighbourhood control group was the one that gave unbiased results. RESULTS: The proportion of controls with scars indicating BCG revaccination was higher among the control group selected from Health Unit attenders than among neighbourhood controls. This excess was not removed after control for social variables and history of exposure to tuberculosis, and appears to have resulted from the fact that people attending the Health Unit were more likely to have been revaccinated than neighbourhood controls, although we can not exclude an effect of other unmeasured variables. CONCLUSION: In this study, controls selected from people presenting to a Health Unit overrepresented exposure to BCG revaccination. Had the results from the HU attenders control group been accepted this would have resulted in overestimation of vaccine efficacy. When the exposure of interest is offered in a health facility, selection of controls from attenders at the facility may result in over representation of exposure in controls and selection bias
Micro-arc oxidization of a novel Mg-1Ca alloy in three alkaline KF electrolytes: Corrosion resistance and cytotoxicity
No full textA newly-developed Mg-1Ca (wt%) alloy was treated by micro-arc oxidization (MAO) in KF-silicate- (Si coating), KF-phosphate- (P coating) and KF-silicate-phosphate (SiP coating) electrolytes. The microstructure, composition and corrosion resistance of the resultant MAO coatings were investigated using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffractometry (XRD). Electrochemical analysis and immersion test in Hanks' solution and MU assay for in-vitro toxicity against MG63 cells were subsequently carried out. Results showed that all the three MAO coatings contributed to the improvement of corrosion resistance and cytocompatibility of substrate; however, P coating outperformed the two others due to its specific microstructure and composition. (C) 2013 Elsevier B.V. All rights reserved.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000330208500143&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Chemistry, PhysicalMaterials Science, Coatings & FilmsPhysics, AppliedPhysics, Condensed MatterSCI(E)[email protected]
The missing link in linear alkylbenzenesulfonate surfactant degradation : 4-sulfoacetophenone as a transient intermediate in the degradation of 3-(4-sulfophenyl) butyrate by comamonas testosteroni KF-1
No full textBiodegradation of the laundry surfactant linear alkylbenzenesulfonate (LAS) involves complex bacterial communities. The known heterotrophic community has two tiers. First, all LAS congeners are oxygenated and oxidized to about 50 sulfophenylcarboxylates (SPC). Second, the SPCs are mineralized. Comamonas testosteroni KF-1 mineralizes 3-(4-sulfophenyl)butyrate (3-C4-SPC). During growth of strain KF-1 with 3-C4-SPC, two transient intermediates were detected in the culture medium. One intermediate was identified as 4-sulfoacetophenone (SAP) (4-acetylbenzenesulfonate) by nuclear magnetic resonance (NMR). The other was 4-sulfophenol (SP). This information allowed us to postulate a degradation pathway that comprises the removal of an acetyl moiety from (derivatized) 3-C4-SPC, followed by a Baeyer-Villiger monooxygenation of SAP and subsequent ester cleavage to yield SP. Inducible NADPH-dependent SAP-oxygenase was detected in crude extracts of strain KF-1. The enzyme reaction involved transient formation of 4-sulfophenol acetate (SPAc), which was completely hydrolyzed to SP and acetate. SP was subject to NADH-dependent oxygenation in crude extract, and 4-sulfocatechol (SC) was subject to oxygenolytic ring cleavage. The first complete degradative pathway for an SPC can now be depicted with 3-C4-SPC: transport, ligation to a coenzyme A (CoA) ester, and manipulation to allow abstraction of acetyl-CoA to yield SAP, Baeyer-Villiger monooxygenation to SPAc, hydrolysis of the ester to acetate and SP, monooxygenation of SP to SC, the ortho ring-cleavage pathway with desulfonation, and sulfite oxidation.publishe
What is a pilot or feasibility study? A review of current practice and editorial policy
No full textBackground: In 2004, a review of pilot studies published in seven major medical journals during 2000-01 recommended that the statistical analysis of such studies should be either mainly descriptive or focus on sample size estimation, while results from hypothesis testing must be interpreted with caution. We revisited these journals to see whether the subsequent recommendations have changed the practice of reporting pilot studies. We also conducted a survey to identify the methodological components in registered research studies which are described as 'pilot' or 'feasibility' studies. We extended this survey to grant-awarding bodies and editors of medical journals to discover their policies regarding the function and reporting of pilot studies.
Methods: Papers from 2007-08 in seven medical journals were screened to retrieve published pilot studies. Reports of registered and completed studies on the UK Clinical Research Network (UKCRN) Portfolio database were retrieved and scrutinized. Guidance on the conduct and reporting of pilot studies was retrieved from the websites of three grant giving bodies and seven journal editors were canvassed.
Results: 54 pilot or feasibility studies published in 2007-8 were found, of which 26 (48%) were pilot studies of interventions and the remainder feasibility studies. The majority incorporated hypothesis-testing (81%), a control arm (69%) and a randomization procedure (62%). Most (81%) pointed towards the need for further research. Only 8 out of 90 pilot studies identified by the earlier review led to subsequent main studies. Twelve studies which were interventional pilot/feasibility studies and which included testing of some component of the research process were identified through the UKCRN Portfolio database. There was no clear distinction in use of the terms 'pilot' and 'feasibility'. Five journal editors replied to our entreaty. In general they were loathe to publish studies described as 'pilot'.
Conclusion: Pilot studies are still poorly reported, with inappropriate emphasis on hypothesis-testing. Authors should be aware of the different requirements of pilot studies, feasibility studies and main studies and report them appropriately. Authors should be explicit as to the purpose of a pilot study. The definitions of feasibility and pilot studies vary and we make proposals here to clarify terminology
Chain extension reaction catalyzed by KF exo− in the presence of the modified triphosphate d(7-Ni)TP
No full text<p><b>Copyright information:</b></p><p>Taken from "Hybridization properties and enzymatic replication of oligonucleotides containing the photocleavable 7-nitroindole base analog"</p><p>Nucleic Acids Research 2005;33(5):1532-1543.</p><p>Published online 14 Mar 2005</p><p>PMCID:PMC1065254.</p><p>© The Author 2005. Published by Oxford University Press. All rights reserved</p> Experiments were investigated on different natural templates (100 nM) varying by the nature of the base N19 (N = T, sequence 13; N = C, sequence 14; N = G, sequence 15; N = A, sequence 16) hybridized to 18mer primer (sequence 12, 50 nM). In a first step, chain extension reactions were conducted in the presence of d(7-Ni)TP (1 mM) and KF exo− (0.0625 U/μl) for 5 min at 30°C (lanes 2, 6, 10 and 14). In the second step, reactions were carried out using KF exo− (0.0125 U/μl) in the presence of dATP (lanes 3, 7, 11 and 15) or in the presence of a mixture of the four dNTPs (lanes 4, 8, 12 and 16) for 20 min at 30°C
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