Stability characteristics and applications of native and chemically-modified horseradish peroxidases

Due to its inherent stability, ease of handling and availability, horseradish peroxidase (HRP) will continue to be used more extensively in analytical and industrial situations. It is often used as a model for other peroxidases. Developments in the fields of protein stabilisation and biosensor construction are discussed in Chapter one; also, various enzymatic methods for treating phenolic effluents are reviewed. The effects of chemical modifiers on native HRP were investigated (Chapter two). Homobifunctional crosslinkers specific for lysine residues were employed. No loss of enzyme activity occured on reaction with such Nhydroxysuccinimide (NHS) compounds. Derivative forms of HRP displayed greater thermostability and a greater tolerance of water-miscible organic solvents. Enhanced resistance towards dénaturants was noted. Structural changes in the vicinity of the heme of HRP derivatives were studied by UV/Visible spectrophotometry and fluorimetry. The extent of modification on HRP’s six lysines has been determined. The NHS derivatives of HRP have also been employed in the removal of phenols from aqueous solution (Chapter three). HRP catalyses the oxidation of toxic aromatic compounds in the presence of hydrogen peroxide. Reaction products polymerise to form high molecular weight materials which can be easily separated from aqueous solution. Modified peroxidases displayed greater removal efficiencies of phenols compared to the native enzyme over a wide range of reaction conditions, including high temperatures. For some pollutants, the efficiency of removal is high. Native HRP has also been used in the development of a biosensor for the selective determination of uric acid (Chapter four). The sensor was found to function efficiently without the necessity for an electron transfer mediator. The mechanism of the sensor’s response was thought to be due to direct electron transfer from the electrode to HRP. A monomer, o-aminophenol, which was electrodeposited at the working surface of the electrode, was found to protect the biocomponents from interferences and fouling. The sensor was incorporated into a flow injection system for the quantification of uric acid in human serum. Recoveries compared favourably with a standard spectrophotometric method

Study on the Application of Lesson Study in Increasing the Effectiveness of Learning Practices at SDN 15 Mataram

In essence, pupils have a right to education. However, a sizable portion of the class still doesn't study. The learning outcomes are not ideal since many pupils do not learn. It is stated that learning is ineffective since a large number of pupils' learning results are subpar. This is why lesson study, a teacher forum, is necessary to enhance learning and make it more efficient. In light of this backdrop, the research's goals are to: a) assess the degree of lesson study implementation at SDN 15 Mataram. b) to evaluate if lesson study has a positive impact on SDN 15 Mataram's instructional methods. There is descriptive qualitative research in this study. Using percentages and values, the information gathered through observation and interviews was examined. The use of lesson study at SDN 15 Mataram can improve learning practices, according to the findings and analysis of the research data, which show that: a) the implementation of lesson study there is adequate

Accuracy of Death Certificate Data in Reporting Suicide in the United States

Suicide is one of the leading causes of death in the United States. Death certificates are currently being used by public health professionals and policy makers as a main source of public health surveillance data on suicide. The accuracy of death certificates in tracking and reporting suicides has not been well quantified or evaluated in the United States. Death certificates from other countries have been found to under-report suicide. The purpose of this study was to evaluate the accuracy of death certificates in reporting suicides in the United States. The National Violence Death Reporting System (NVDRS) collects information on all violent deaths from multiple sources including medical records, law enforcement reports, and vital records. Suicide cases recorded in the NVDRS data from 2003 through 2017 were used as a reference standard to evaluate the accuracy of death certificates in reporting suicide in the United States (n = 201,912). Using a multifactorial conceptual framework and a quantitative cross-sectional design, several risk factors were analyzed to determine if they influenced the accurate reporting of suicide on the death certificate. Using a binomial logistic regression model, 13.4% (Nagelkerke R2 = .134) of the variation in accuracy can be attributed to age, race, marital status, education, method of suicide, substance abuse status, year, and state. This study establishes that the death certificate is highly accurate (99.57%) at reporting suicide deaths overall. Therefore, death certificate data can be used as an accurate data source upon which to base public health decisions, interventions, and tracking. It is important that policy and intervention decisions be based on accurate data to effectively and efficiently influence social change

Gender, Excellence and Academic Research Funding : A quantitative study of the relationship between gender and excellence in Norwegian research funding programmes

Master's thesis Public Policy and Management ME502 - University of Agder 2017This thesis investigates the relationship between excellence and gender in academic research funding. Previous research conducted in Scandinavia has shown that excellence efforts might be damaging for gender equality. I reassess this hypothesis by comparing the application behaviour and successfulness in obtaining research funding of women and men across two highly competitive funding schemes in Norway: one that explicitly stresses excellence in the programme title (the Centre of Excellence programme) and one that does not (the Independent Projects programme). Grounded in organisation theory, I hypothesis that organisational factors, such as organisational learning cumulating over time affects how men and women respond to organisational stimuli, such as excellence. My main findings suggest women are generally less likely to apply as centre leaders in the Centre of Excellence scheme, even when adjusting for the composition of the pool of potential applicants based on researchers’ academic rank. However, women are as likely as men to apply in more recent calls (given the number of potential applicants). Comparing success rates for men and women, the results show that women outperform men in both funding programmes, but this difference is generally substantially larger in the Centre of Excellence scheme. This implies that there may be a self-selection effect at play among women when stressing excellence in research funding. However, after conducting logistic regression, there seem to be no statistically significant covariation between gender and being granted or not

Reporting and interpreting the numerical results of a vaccine trial: a practical guide for students and health care professionals

In one year, the COVID pandemic has changed the world. Universities, pharmaceutical companies, and many other organisations worldwide worked effortlessly to develop vaccines to ease the socioeconomic burden of the disease and improve global health care. Nowadays, vaccine efficacy is a very popular term; but do we know what it means and how to calculate it? This article provides information on reporting and interpreting the numerical results of a vaccine trial. It aims to be a practical guide for students and health care professionals. It gives a simple definition of the common terminology, the vaccine efficacy, how to calculate it, and how the confidence interval can be found (though formulae for the latter are not given here). Additionally, it provides two simple examples (A, B), including the formulae for calculating the vaccine efficacy explaining the differences of vaccine efficacy between the two examples simply and pragmatically

Vaccine efficacy: The implication of using odds ratio and relative risk for the calculation. Which one would you choose?

During the last 12 months, COVID-19 became a global problem. Universities and drug companies are working together for the development of treatments. Vaccines appear to be one of the most promising treatments, and trials are completed, and others are ongoing. All these studies tend to use a common comparator, the percentage of vaccine efficacy (VE%), calculated using the following formula VE=(1-RR) x100. A recent study published in a renowned medical journal presented large trial results using a different formula VE=(1-OR) x100. We compared the analysis using relative risk (RR) versus an odds ratio (OR), and we did not find any large difference in the results. Nevertheless, we would advise using RR instead of OR in the interests of accuracy, for best practice

Consensus mutagenesis reveals that non-helical regions influence thermal stability of horseradish peroxidase

The enzyme horseradish peroxidase has many uses in biotechnology but a stabilized derivative would have even wider applicability. To enhance thermal stability, we applied consensus mutagenesis (used successfully with other proteins) to recombinant horseradish peroxidase and generated five single-site mutants. Unexpectedly, these mutations had greater effects on steady-state kinetics than on thermal stability. Only two mutants (T102A, T110V) marginally exceeded the wild type's thermal stability (4% and 10% gain in half-life at 50 °C respectively); the others (Q106R, Q107D, I180F) were less stable than wild type. Stability of a five-fold combination mutant matched that of Q106R, the least-stable single mutant. These results were perplexing: the Class III plant peroxidases display wide differences in thermal stability, yet the consensus mutations failed to reflect these natural variations. We examined the sequence content of Class III peroxidases to determine if there are identifiable molecular reasons for the stability differences observed. Bioinformatic analysis validated our choice of sites and mutations and generated an archetypal peroxidase sequence for comparison with extant sequences. It seems that both genetic variation and differences in protein stability are confined to non-helical regions due to the presence of a highly conserved alpha-helical structural scaffold in these enzymes

Effects of mutations in the helix G region of horseradish peroxidase

Horseradish peroxidase (HRP) has long attracted intense research interest and is used in many biotechnological fields, including diagnostics, biosensors and biocatalysis. Enhancement of HRP catalytic activity and/or stability would further increase its usefulness. Based on prior art, we substituted solvent-exposed lysine and glutamic acid residues near the proximal helix G (Lys 232, 241; Glu 238, 239) and between helices F and F′ (Lys 174). Three single mutants (K232N, K232F, K241N) demonstrated increased stabilities against heat (up to 2-fold) and solvents (up to 4-fold). Stability gains are likely due to improved hydrogen bonding and space-fill characteristics introduced by the relevant substitution. Two double mutants showed stability gains but most double mutations were non-additive and non-synergistic. Substitutions of Lys 174 or Glu 238 were destabilising. Unexpectedly, notable alterations in steady-state Vm/E values occurred with reducing substrate ABTS (2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)), despite the distance of the mutated positions from the active site

Festivalproduksjon og -opplevelse under Covid-19-pandemien

Oppdragsgiver: Nynorsk kultursentrum/Litteraturdagane I VinjeRapporten er resultat av et forsprosjekt som Telemaksforskning og Høgskolen i Innlandet gjorde for oppdragsgiveren Nynorsk kultursentrum/Litteraturdagane i Vinje. Vi ser på hvordan mindre festivaler tilpasset seg Korona-pandemien i 2020 og hvordan deltakere i disse festivalene opplevde tilbudet. De fire festivalene som vi undersøkte (Amandusfestivalen, Digitale festspel 2020, Peer Gynt stemnet og Littearurdagane i Vinje) viste seg å ha svært forskjellige tilbud i 2020. De to første festivalene, Amandus og Digitale festspel 2020, ble i hovedsak gjort om til on-line festivaler, mens de to andre kombinerte fysisk oppmøte med digital formidling. Mens Amandusfestivalen i stor grad beholdt de planlagte programelementene og den samme tidsperioden for avvikling av sitt digitale tilbud ble programelementene for Digitale festspel 2020 lagt på nett fordelt over en tre måneder lang periode. I tillegg til dette arrangerte Digitale festspel to studioproduksjoner i den opprinnelige festivalperioden samt flere innslag utover høsten. Litteraturdagene i Vinje holdt seg til den opprinnelige festivalperioden, men reduserte antall innslag, som nesten alle ble formidlet direkte. Peer Gyntstemnet la om programmet sitt til en minifestival i de helgene der forestillingene egentlig skulle foregå og utvidet med digitale tilbud lokalisert i Gudbrandsdalen. De fire aktørene hentet inn ekstern kompetanse for å ta seg av den tyngste delen av formidlingen, men tilbudet omfattet også noen egenproduserte videoer. Vi ser at alle i første omgang brukte lokal videokompetanse til å stå for produksjon av mer avanserte flerkameraopptak, men de aller mest ressurskrevende delene ble gjennomført i Oslo. Estetisk beholder strømming mye av sceneopptredenen sin karakter, med vekt på å vise fram utøvere og deres budskap. Man kan snakke om en sakte/minimalistisk estetikk med få sceniske elementer, lite bruk av lys som virkemiddel, lange takninger, og ytterst forsiktige kameravekslinger og -bevegelser. Den andre delundersøkelsen ser på hvordan publikum opplevde de digitale arrangementene under Digitale Festspel 2020 og Litteraturdagane i Vinje. Empirien ble hentet inn gjennom en spørreundersøkelse til deltakerne samt intervju av et mindre utvalg. Studien viser først og fremst at langt færre deltok på festivalen når formatet var digitalt. Informantene oppgir at de oppfatter det digitale formatet som et alternativ til det fysiske i en spesiell tid, ikke som et framtidig substitutt. Et fåtall deltar på festivalen fordi den er digital, de aller fleste deltar på tross av at den er digital. Undersøkelsen viser også at festivalen som paraplyarrangement synes å miste sin betydning når plattformen blir digital, det er det enkelte arrangement som blir viktig. Et annet sentralt funn er at informantene i liten grad klarer/ønsker å sammenligne den fysiske festivalen med den digitale. Det indikerer at publikum opplever dette som to helt forskjellige opplevelser. Flere sier at de opplever at den digitale festivalen mest av alt ligner en TV-sending. Undersøkelsen er imidlertid basert på en liten informantgruppe, konklusjonen bør først og fremst brukes som pekepinner for hva som er relevant å undersøke i framtidige prosjekter.Abstract: This report is the result of a preliminary project carried out by Telemark Research Institute and the Inland Norway University of Applied Sciences commissioned by Nynorskkultursentrum/ Litteraturdagane i Vinje. In it we analyse how small festivals in Norway adjusted to the Covid-19 pandemic in 2020 and how the participants experienced their moving online. The investigation focused on four festivals: the Amandus film festival, Digitale festspel 2020, Peer Gynt stemnet and Litteraturdagane i Vinje. The festivals adapted to the situation differently. The two festivals that took place first (Amandus and Digtale festspel 2020) were largely online, while the later ones combined on-location with offline performances. While the Amandus festival to a large extent retained its original programme and timetable, Digitale festspel 2020 spread its online offering over three months, as well as arranging two streamed multi-camera studio productions for the original festival timespan. Litteraturdagane i Vinje retained its original time schedule but the programme which was streamed online was reduced. Peer Gynt was also slimmed down so that it became a mini festival over the weekends of the festival period. In addition, they developed on-location-based digital offerings with sound tours and a hologram with experts of the Peer Gynt performance. The four festivals produced some videos that were available online themselves, but all brought in local video production firms to produce the more complicated parts of the productions. Some of the more resource-heavy parts of the production (multicamera production) were carried out in Oslo. The streaming productions were used for stage-based items, focusing on the actors and their performances. Aesthetically, these were minimalist productions with few scenic elements, little use of lighting, a slow editing pace and little obvious camera movement. The second part of the study examines how the audience experienced the digital events arranged by Digitale Festspel 2020 and Litteraturdagane i Vinje. The empirical material was collected through a survey and through interviews with a smaller group. The study shows first of all that considerably fewer people attended to the festival when digitized, and that the audience experience the digital format primarily as an alternative during a special time – not as a substitute for future festivals. Only a very few informants say they attend to the festival because it is digital and easily accessible, most of them attend in spite of it being digitized. The study also demonstrated how the festival as such loses its meaning when its digital, it is the specific events that matters. Another important finding is that the respondents are reluctant to compare the digital and the physical festival, implying that the audience experience this as two completely different things – incomparable. Many of the informants reports that they experience the digital events as a TV-show. However, the study is based on a small group of informants, the conclusions should therefore be regarded as preliminary and first and foremost useful for further studies.publishedVersio