Microbial Adhesion to Processing Lines for Fish Fillets and Cooked Shrimp: Influence of Stainless Steel Surface Finish and Presence of Gram-Negative Bacteria on the Attachment of Listeria monocytogenes

Microflora adhering to surfaces of processing lines in a shrimp factory and a fish processing plant was identified in situ and adhesion of mixed culture of Listeria monocytogenes and Gram-negative bacteria on stainless steel surfaces (untreated, polished and glass beaded) was studied ex situ. The predominant genus attached to the surfaces was Pseudomonas spp. (66 %) in the shrimp factory and Enterobacteriaceae (27 %) in the fish factory. Shrimp juice was used as an enrichment broth during the study of adhered bacteria. Three different Gram-negative strains and a mixture of Pseudomonas spp. were selected to study their attachment together with L. monocytogenes to stainless steel surfaces. Highest numbers of the attached bacteria were obtained after the contamination with a mixed culture of L. monocytogenes and Serratia liquefaciens. A lower number of bacteria adhered to stainless steel surfaces when mixed cultures of L. monocytogenes and Pseudomonas fluorescens or Aeromonas spp. were tested. No significant differences (p<0.05) were observed in the bacteria attached to differently treated steel surfaces with different roughness (Ra=0.1–0.8 m). Bacterial adhesion increased with longer contact time. Colonisation of L. monocytogenes on stainless steel surfaces was significantly enhanced only in the presence of mixed Pseudomonas spp. These results indicate that smooth surfaces do not necessarily provide hygiene benefits over rougher surfaces

Etikkens levevilkår i naturfag : En studie av hvilke rammer som påvirker lærernes planlegging i i "drøfting av etiske spørsmål i bioteknologi"

STIKKORD: Rammer som påvirker lærernes planlegging Etikkens plass i naturfag Den metabevisste faktor 1) Oppgavens tema og fokusområde: Oppgavens hovedtema er etikkens levevilkår i naturfaget, og fokusområdet er: Hvilke rammer blir bestemmende for naturfaglærernes planlegging av kompetansemålet ”å drøfte etiske spørsmål i bioteknologien”? I forhold til mine funn har jeg drøftet følgende: Hvilken betydning kan rammene få for etikkens levevilkår i naturfag, sett i lys av mine funn og relevant litteratur? Hensikten med studien har vært å få en forståelse av hvordan lærerne legger til rette for drøfting av etiske spørsmål i naturfaget i første klasse på den videregående skolen, og hva som påvirker deres planlegging. De teoretiske refleksjonene som eksisterer i litteraturen i dag har jeg brukt til å belyse mine forskningsfunn. Jeg avslutter med å se på hvilke implikasjoner dette kan få for etikkens levevilkår i naturfag. Teorien, som i hovedsak består av artikler, ble delt inn i tre områder etter deres innhold, og berøringspunkter i forhold til forskningsområdet mitt: lærernes rammer, etikkens plass i naturfaget, og undervisningens struktur. 2) Metode og datamateriale Med hensyn til studiens fokusområde, hvor jeg har søkt etter forståelse, sammenhenger og innsikt, ble det naturlig å bruke en kvalitativ metode. Jeg foretok semistrukturerte intervju av fire naturfaglærere fra samme skole. Valg av et tillempet grounded analyseopplegg, ga meg mulighet til å finne andre kategorier og forståelsessammenhenger enn det som allerede eksisterer på forskningsfeltet. 3) Funn Jeg fant at de rammene som ble bestemmende for lærernes planlegging av nevnte kompetansemål kunne underlegges to hovedkategorier: lærernes indre rammer, og lærernes ytre rammer (figur 1). Figur 1. Forklaringsmodell som viser interaksjonen mellom lærerens indre og ytre rammekategorier, som en pådriver inn til lærerens undervisningsplan. To kategorier finnes også i svenske undersøkelser som forklaring på lærernes planlegging/undervisning. Disse kategoriene inngår i min forklaringsmodell, men i tillegg har jeg funnet at kategorien ”lærerens vitenskapssyn” har avgjørende betydning for hvordan læreren velger å forholde seg til rammekategoriene. Lærernes tolkninger av de ytre rammene og deres holdninger til de indre rammene, i tillegg til ytre rammer som avgjøres på sentralt hold, får derfor avgjørende betydning for etikkens levevilkår i naturfaget

Energikartläggning av idrottsanläggningar - fallstudie av en ishall och ett badhus i norra Landskrona

Detta examensarbete är skrivet inom ramen för Green Hub Landskrona (GHL), som är ett samarbete mellan tre kommunala företag i Landskrona och flera institutioner inom Lunds Universitet - LTH. Syftet med samarbetet är att driva omställningen av stadsdelen Karlslund till en hållbar stadsdel genom innovativa lösningar för energi, avfall och boende. Detta examensarbete utförs som ett första steg i denna omställning. Arbetets syfte är delvis att kartlägga energianvändningen av två energikrävande anläggningar i området, nämligen Landskrona ishall och Karlslundsbadet. Det andra syftet är att utvärdera befintliga riktlinjer för energikartläggningar utifrån hur väl de stämmer överens med varandra, vilka aspekter de lyfter fram, vilka begränsningar de har samt hur väl de kan appliceras på idrottsanläggningar. Fyra riktlinjer har analyserats i arbetet varav Energimyndighetens riktlinjer har använts i de genomförda kartläggningarna på idrottsanläggningarna, men vissa anpassningar har gjorts utifrån tillgänglig data. Anläggningarna var dels en ishall, av typen mindre publikhall, med en utomhusisbana och ett äventyrsbad med en liten utomhusbassäng. Båda anläggningarna var försörjda med el från det koncessionspliktiga nätet och med fjärrvärme. I början av kartläggningsprocessen berättade anläggningarnas driftpersonal att det aktiva arbetet med energihushållning i anläggningarna tidigare varit mycket begränsat och främst utförts i samband med underhållsbehov. Energikartläggningarna utfördes bland annat genom en rad platsbesök där intervjuer hölls med personal, styrsystem studerades och installerad effekt avlästes från de olika komponenterna. Kartläggningarnas resultat jämfördes med genomsnittsdata för liknande anläggningar i Sverige, från Energimyndighetens inventering av energianvändningen i olika lokaler, benämnd STIL2. Det visade sig att anläggningarna använde allt från 20 % till fyra gånger mer energi än genomsnittet i STIL2. Karlslundsbadet avvek betydligt mer från genomsnittet än ishallen, men avvikelsernas storlek berodde på om energianvändningen jämfördes utifrån uppvärmd area, verksamhetsarea eller efter antal öppettimmar. Energikartläggningarna fokuserades på elanvändingens fördelning utifrån dess olika användingsområden, såsom pumpar, fläktar och kylmaskiner. I ishallen visade kartläggninen att kylmaskinerna stod för nästan 50 % av elanvändningen, avfuktare för cirka 17 % och diverse pumpar för runt 9 %. I Karlslundsbadet stod fläktar för 36 %, bastur för 26 % och diverse pumpar för 25 % av elanvändningen. I både Karlslundsbadet och Landskrona ishall antogs elanvändningen för utrustningen som av olika anledningar inte kunnat inventeras, främst utifrån data från STIL2 studien, vara 4,6 % respektive 12 %. Även belysningen för de två anläggningarna inventerades. Inventeringen visade att Karlslundsbadets installerade effekt var lägre än genomsnittet för badhus medan ishallens installerade effekt var högre än genomsnittet för ishallar. Det kan dock konstateras att båda anläggningarna har en stor förbättringspotential vad gäller åtgärder för att minska elanvändningen för belysning. I enlighet med rapportens andra syfte utvärderades Energimyndighetens riktlinjer utifrån hur tillförlitligt resultatet blev för de två studerade idrottsanläggningarna. I riktlinjerna föreslås att energianvändningen för respektive komponent beräknas utifrån installerad effekt och drifttider där befintlig data inte finns. Storleken på de differenser som kan föreligga mot uppmätta värden, vid använding av denna metodik, har utvärderats inom ramen för denna studie. Utvärderingen har visat att den använda metodiken leder till att den beräknade elanvändningen överskattas grovt i vissa fall. I Karlslundsbadet överskattades den med 35 % och i ishallen med 140 %. Källan till överskattningen var avvikelser i komponenternas aktuella effekt från den installerade effekten och skillnader i total och effektiv drifttid. Dessa överskattningar påverkade de olika användningsområdena i varierande grad, vilket i sin tur ledde till snedfördelningar av respektive användningsområdes andel av elanvändningen. Detta har styrkts bl.a. genom mätningar av kompressorernas eleffekt över en kortare tid i ishallens kylmaskin och är viktigt att ha i åtanke när resultaten tolkas. Analysen av de befintliga riktlinjerna för energikartläggningar visade på stora skillnader i deras struktur, omfattning och detaljnivå. Variationerna var även stora vad gäller deras beskrivning av insamlande av data och valet av åtgärder. Riktlinjerna tar däremot inte upp något om vilka felkällor som kan uppstå vid användandet av installerad effekt och drifttider eller hur dessa ska hanteras vid en genomförd kartläggning utifrån riktlinjerna. Riktlinjerna från Energimyndigheten uppger att de användningsområden som står för en betydande del av energianvändningen är de som borde studeras vid sökandet efter möjliga åtgärder. Detta angreppssätt går Energimyndigheten själv emot i sin bok, Energikoll i små och medelstora företag. Generellt för alla riktlinjer var att de lägger stor vikt vid de ekonomiska kalkylerna för en åtgärd. ISO-standarden var den enda som även lyfte fram vikten av att andra aspekter än ekonomi kan anses vara viktiga vid valet av åtgärder. Utifrån genomförda fallstudie konstaterades att var och en av riktlinjerna i sin helhet inte fungerar för anläggningar motsvarade Karlslundsbadet och Landskrona ishall.This Master´s thesis is a part of the project Green Hub Landskrona (GHL), a collaboration between three municipally owned companies in Landskrona and a number of institutions within the faculty of engineering at Lund University. The aim of GHL is to transform the neighbourhood Karlslund, northern Landskrona, to a sustainable district, through innovative solutions for energy, waste management and housing. As a first step towards this transformation, the aim of this thesis is partly to carry out energy audits of two of the neighbourhood’s facilities with particularly high energy consumption. These facilities are the city’s only ice rinks, Landskrona ishall, and the city’s main public swimming pool, Karlslundsbadet. The second aim is to evaluate existing guidelines for energy audits based on how well they match with each other, which aspects they emphasize, what their limitations are and how well they can be applied to sports facilities. Four guidelines were evaluated and the energy audits of the facilities were performed according to guidelines from the Swedish Energy Agency (SEA), with certain adjustments to available data. The indoor ice rink is relatively simple, with audience capacity of 1400 people and includes an adjacent outdoor ice rink. The swimming pool is, however, somewhat more sophisticated, with a small outdoor pool and features water play areas, such as slides and whirlpools indoors. According to the staff in charge of the facilities’ operation, the emphasis on energy economisation had been very limited prior to the execution of this thesis. Earlier efforts to reduce the energy consumption of the facilities have mainly been motivated by maintenance requirements. The energy audits were carried out through a number of site visits where staff members of the facilities were interviewed, the control systems studied and the components’ installed electric power surveyed etc. The results for each facility were compared to the average outcome of similar facilities in a study of different facilities energy consumption by the SEA from 2008, called STIL2. It was shown that the facilities used everything from 20% to four times more energy than similar facilities in Sweden. The results did, however, vary greatly depending on which indicators were used. The main focus of the energy audits was on the distribution of the electricity consumption in the facilities. In the case of Landskrona ishall nearly half of all electricity was used by the chillers. The second largest consumer of electricity was the dehumidifier with 17%, followed by various pumps with 9%. The distribution in Karlslundsbadet was quite different, where fans used 36%, saunas used 26% and various pumps used 25% of the electricity consumption. In both facilities, the electricity consumption of equipment, that for various reasons could not be identified, was quantified by assumptions based on data from the STIL2 study. In the case of Karslundsbadet this consumption accounted for 4,6% but for 12% in Landskrona ishall. The facilities’ lighting systems were studied more thoroughly than other systems. The results showed that Karlslundsbadet performed better than the average of similar facilities in Sweden, even though the potential for improvement was great. For Landskrona ishall the situation was somewhat worse than in similar facilities. In accordance with the report's second aim the guidelines from SEA were evaluated on the basis of how reliable the results for the two facilities were. The guidelines recommended that available data should be used primarily. In its absence, data on components’ installed electric power and operation time should be used to calculate the energy consumption. The effect of using this methodology has been evaluated within the framework of this study. The evaluation revealed that it lead to an overestimation of the facilities’ electricity consumption to an extent that greatly exceeded the actual consumption. In the case of Landskrona ishall the overestimation amounted to 140% of the actual consumption, whilst it was only 35% in the case of Karlslundsbadet. The reasons for this inaccuracy were both fluctuations in the components’ electrical power and difficulties in quantifying their operation time correctly. The overestimations affected the different systems to a varying extent and thereby the relative distribution of the electricity consumption. This has mainly been supported by data collected, over a short period of time, for the electrical power of the chiller’s compressors in Landskrona ishall. The analysis of the presented guidelines for energy audits revealed great differences in structure, extent and accuracy of description. Even in respect to the collection of data and the selection of energy efficiency improvement opportunities, the differences were significant. The inaccuracy caused by the use of components’ installed electric power and operation time was not mentioned in the guidelines. For the selection of energy efficiency improvement opportunities, the guidelines from SEA recommended further studies of systems that account for a significant share of the facilities’ energy consumption. This focus was presented as a problem in a book published by SEA, Energikoll i små och medelstora företag. The focus on economic indicators, during the selection process, was great in all the studied guidelines. Only the guidelines in the ISO standard highlighted the importance of the additional aspects in the selection process. Based on this case study it was concluded that the studied guidelines for energy audits were not well suited for facilities like Karlslundsbadet and Landskrona ishall

A Comparison of Fresh and Frozen Lamb Meat-Differences in Technological Meat Quality and Sensory Attributes

Simple Summary Freezing is used to extend the storage time of meat and is common practice in lamb meat production, since it maintains a steady supply of seasonal meat throughout the year and allows shipping over long distances. Fresh meat may also be purchased and frozen at home, to enable longer storage of the product before consumption. Freezing is the best preservation method, apart from chilling of fresh meat. However, differences in quality parameters between fresh and frozen meat may influence consumer choice and preferences. It is thus important to evaluate these differences, and how they are affected by conditions and animal handling during primary production, slaughter method and storage conditions before retail sale. This study examined the effect of freezing on technological meat quality and sensory attributes in lamb meat samples collected at two different slaughterhouses using different slaughter methods. Several differences between fresh and frozen-thawed meat were detected in terms of technological meat quality and sensory attributes, including colour, Warner-Bratzler shear force, cooking loss, flavour attributes and juicy texture. Technological meat quality and sensory attributes of fresh and frozen lamb meat were compared. Samples were collected from two abattoirs (one small-scale, one large-scale) that use different slaughter methods in terms of chilling regime and electrical stimulation. The fresh and frozen meat samples included products from both slaughter systems. Ten twin pairs of ram lambs were used in the study, with one of each twin slaughtered at each abattoir. Fresh meat was analysed after chilling and frozen meat was stored frozen for three months and analysed after thawing. The Musculus longissimus thoracis et lumborum was analysed for colour, cooking loss, sensory attributes, Warner-Bratzler shear force (WBSF) and distribution of water and lipid within each meat sample. Meat samples analysed after frozen storage were darker, less red and more yellow than the fresh meat. Freezing and frozen storage increased fluid loss and WBSF compared with the fresh meat, due to protein denaturation. Frozen storage affected sensory attributes by increasing fatty odour, frying flavour, sour flavour, fatty flavour and liver flavour, and by reducing juicy texture and mushy texture

Recruitment of trimeric eIF2 by phosphatase non-catalytic subunit PPP1R15B

Regulated protein phosphorylation controls most cellular processes. The protein phosphatase PP1 is the catalytic subunit of many holoenzymes that dephosphorylate serine/threonine residues. How these enzymes recruit their substrates is largely unknown. Here, we integrated diverse approaches to elucidate how the PP1 non-catalytic subunit PPP1R15B (R15B) captures its full trimeric eIF2 substrate. We found that the substrate-recruitment module of R15B is largely disordered with three short helical elements, H1, H2, and H3. H1 and H2 form a clamp that grasps the substrate in a region remote from the phosphorylated residue. A homozygous N423D variant, adjacent to H1, reducing substrate binding and dephosphorylation was discovered in a rare syndrome with microcephaly, developmental delay, and intellectual disability. These findings explain how R15B captures its 125 kDa substrate by binding the far end of the complex relative to the phosphosite to present it for dephosphorylation by PP1, a paradigm of broad relevance.</p

A Comparison of Fresh and Frozen Lamb Meat—Differences in Technological Meat Quality and Sensory Attributes

Funding Information: This research was funded by Agricultural Productivity Fund of Iceland, Nordic Native Meat and the Swedish University of Agricultural Sciences. Publisher Copyright: © 2022 by the authors.Technological meat quality and sensory attributes of fresh and frozen lamb meat were compared. Samples were collected from two abattoirs (one small-scale, one large-scale) that use different slaughter methods in terms of chilling regime and electrical stimulation. The fresh and frozen meat samples included products from both slaughter systems. Ten twin pairs of ram lambs were used in the study, with one of each twin slaughtered at each abattoir. Fresh meat was analysed after chilling and frozen meat was stored frozen for three months and analysed after thawing. The Musculus longissimus thoracis et lumborum was analysed for colour, cooking loss, sensory attributes, Warner-Bratzler shear force (WBSF) and distribution of water and lipid within each meat sample. Meat samples analysed after frozen storage were darker, less red and more yellow than the fresh meat. Freezing and frozen storage increased fluid loss and WBSF compared with the fresh meat, due to protein denaturation. Frozen storage affected sensory attributes by increasing fatty odour, frying flavour, sour flavour, fatty flavour and liver flavour, and by reducing juicy texture and mushy texture.Peer reviewe

Fractionation of cellulose nanocrystals : enhancing liquid crystal ordering without promoting gelation

Colloids of electrically charged nanorods can spontaneously develop a fluid yet ordered liquid crystal phase, but this ordering competes with a tendency to form a gel of percolating rods. The threshold for ordering is reduced by increasing the rod aspect ratio, but the percolation threshold is also reduced with this change; hence, prediction of the outcome is nontrivial. Here, we show that by establishing the phase behavior of suspensions of cellulose nanocrystals (CNCs) fractionated according to length, an increased aspect ratio can strongly favor liquid crystallinity without necessarily influencing gelation. Gelation is instead triggered by increasing the counterion concentration until the CNCs lose colloidal stability, triggering linear aggregation, which promotes percolation regardless of the original rod aspect ratio. Our results shine new light on the competition between liquid crystal formation and gelation in nanoparticle suspensions and provide a path for enhanced control of CNC self-organization for applications in photonic crystal paper or advanced composites