Breast compression across consecutive examinations among females participating in BreastScreen Norway

Objectives Breast compression is used in mammography to improve image quality and reduce radiation dose. However, optimal values for compression force are not known, and studies has found large variation in use of compression forces between breast centres and radiographers. We investigated breast compression, including compression force, compression pressure and compressed breast thickness across four consecutive full field digital mammography (FFDM) screening examinations for 25,143 subsequently screened women aged 50-69 years. Methods Information from women attending four consecutive screening examinations at two breast centres in BreastScreen Norway during January 2007 - March 2016 was available. We compared the changes in compression force, compression pressure and compressed breast thickness from the first to fourth consecutive screening examination, stratified by craniocaudal (CC) and mediolateral oblique (MLO) view. Results Compression force, compression pressure and compressed breast thickness increased relatively by 18.3%, 14.4% and 8.4% respectively, from first to fourth consecutive screening examination in CC view (p<0.001 for all). For MLO view, the values increased relatively by 12.3% for compression force, 9.9% for compression pressure and 6.9% for compressed breast thickness from first to fourth consecutive screening examination (p<0.001 for all). Conclusions We observed increasing values of breast compression parameters across consecutive screening examinations. Further research should investigate the effect of this variation on image quality and women’s experiences of discomfort and pain

Development of a phantom to test fully automated breast density software – a work in progress

Objectives: Mammographic density (MD) is an independent risk factor for breast cancer and may have a future role for stratified screening. Automated software can estimate MD but the relationship between breast thickness reduction and MD is not fully understood. Our aim is to develop a deformable breast phantom to assess automated density software and the impact of breast thickness reduction on MD. Methods: Several different configurations of poly vinyl alcohol (PVAL) phantoms were created. Three methods were used to estimate their density. Raw image data of mammographic images were processed using Volpara to estimate volumetric breast density (VBD%); Hounsfield units (HU) were measured on CT images; and physical density (g/cm3) was calculated using a formula involving mass and volume. Phantom volume versus contact area and phantom volume versus phantom thickness was compared to values of real breasts. Results: Volpara recognized all deformable phantoms as female breasts. However, reducing the phantom thickness caused a change in phantom density and the phantoms were not able to tolerate same level of compression and thickness reduction experienced by female breasts during mammography. Conclusion: Our results are promising as all phantoms resulted in valid data for automated breast density measurement. Further work should be conducted on PVAL and other materials to produce deformable phantoms that mimic female breast structure and density with the ability of being compressed to the same level as female breasts. Advances in knowledge: We are the first group to have produced deformable phantoms that are recognized as breasts by Volpara software

Comparison of the effects of 6 weeks of squat training with a plyometric training programme upon different physical performance tests in adolescent team handball players

The purpose of this study was to compare the effects of six weeks of squat training with those of plyometric training upon different types of physical performance in adolescent male and female team handball players. Twenty-six adolescent male and female team handball players (age 13.8±0.5 yr, body mass 57.5±11.5 kg, body height 1.70±0.10 m) participated in the study. Half of the subjects (n=13) conducted a squat training program, while the other half conducted a plyometric training program, twice a week for six weeks, in addition to their normal team handball practice. Both groups increased their performance after six weeks in agility, 30 m sprint and Yo-Yo IR1 tests, while no changes were found in the CMJ, strength test and throwing velocity. The results suggest that either a short in-season 6-week squat orplyometric training regimen can improve the physical performance of the lower body, while these programs will not enhance the performance of the upper body

Numerics-informed neural networks and inverse problems with hyperbolic balance laws

Vi introduserer numerikkbevisste nevrale nettverk (NINN), et rammeverk utviklet for å lære kildeledd i hyperbolske partielle differensialligninger. NINN kombinerer klassiske numeriske metoder med nevrale nettverk for å løse inverse problemer knyttet til disse ligningene. I dette arbeidet presenterer vi det generelle rammeverket sammen med et konvergensresultat som relaterer feilen i kildeapproksimasjonen til treningsfeilen. For å håndtere treningen utvikler vi to spesialiserte algoritmer tilpasset ulike bruksområder, og evaluerer ytelsen på et hyperbolsk system. Spesielt muliggjør sweeping-algoritmen bruk av NINN i scenarier der komplette målinger av løsningen ikke er tilgjengelige. Vi tester den foreslåtte metoden grundig på en rekke ulike problemer og sammenligner ytelsen under varierende mengder data. I tillegg er det utviklet et Python-bibliotek for differensierbar simulering av hyperbolske partielle differensialligninger i kombinasjon med denne avhandlingen. Vårt arbeid viser potensialet til NINN som et kraftig verktøy for å løse inverse problemer med hyperbolske partielle differensialligninger og legger grunnlaget for fremtidige fremskritt på dette feltet.We introduce numerics-informed neural networks (NINN), a framework designed to learn source terms in hyperbolic partial differential equations. NINNs combine classic numerical schemes with neural networks to accurately solve inverse problems related to these equations. In this work, we present the general framework, along with a convergence result that relates the source approximation error to the training loss. To implement training, we develop two specialized algorithms tailored for different usecases, and evaluate their performance on a hyperbolic system. The sweeping algorithm, in particular, enables the use of NINNs in scenarios where complete solution measurements are unavailable. We extensively test the proposed method on a diverse set of problems, comparing its performance under varying data quantities. In combination with this thesis, a Python library for performing differentiable simulation of hyperbolic partial differential equations was developed. Our work showcases the potential of NINNs as a powerful tool for solving inverse problems with hyperbolic partial differential equations, paving the way for future advancements in this field

Travel Series as TV Entertainment: Genre characteristics and touristic views on foreign countries

Why is it not the deprived developing country, but rather the tempting destination the host arrives in when guiding the audience in a travel series? And how can we explore the specific combination of entertainment and education that travel series represent? Basically the travel series genre is a hybrid of journalistic documentary, entertaining lifestyle series and TV ads and the different series put different emphasis on the different genre elements. Travel series represent a certain kind of mediated consumption and they reflect lifestyle identity in relation to touristic consumer cultures. Like other lifestyle series dealing with consumption products and lifestyle markers encompassing fashion, food, garden, design and interior that balance somewhere between journalism and advertising, travel series typically deal with destinations, travel modes, cultural experiences and food as commodities. To understand the cultural and democratic value of travel series as a popular TV genre in the context of public service broadcasting, it is not the fact that the series contain educative and enlightening information about foreign cultures told in an entertaining and popular way that are of my interest. Rather it is tourism and media consumer culture as such, one has to expound as valuable democratic and cultural practice. The article presents different matrices of the respectively cultural and consumer knowledge that the different types of travel series include.Rejseserier som tv-underholdning: Teoretisk ramme for analyse af en genre samt sofaturistens blik på fremmede kulturer Hvorfor er det ikke de undertrykte udviklingslande men derimod de fristende rejsemål som programværten omtaler i rejseserierne når han guider tv-seeren til nye og fremmedartede steder på jorden? Og hvordan kan vi forstå den særlige blanding af let underholdning, geografilektion og fristende billeder som er i spil i disse serier? Artiklen beskriver rejseserier som en hybridgenre med rødder i henholdsvis journalistisk dokumentar, en faktuel tv-underholdningsgenre som livsstilsprogrammer samt reklame. De forskellige serier vægtlægger og kombinerer de forskellige genreelementer på forskellige måder. Rejseserier repræsenterer en særlig form for medieret forbrug og de reflekterer livsstile og turisttyper som vi kender fra moderne turisme (backpackeren, eventyreren, storbyturisten, campisten). På samme måde som livsstilsserier der balancerer mellem journalistik og reklame for forskellige produkter og livsstilsmarkører ift. mode, mad, have, design og indretning, omhandler rejseserier typisk rejsemål, rejseformer, seværdigheder og mad som attraktive turistoplevelser. Artiklen præsenterer en teoretisk ramme for at belyse forskellige kommunikative modi samt sofaturistens blik på verden i rejseserier. For at forstå de kulturelle og demokratiske værdier af rejseserier som en populær tv-genre i forhold til public service medier, så er det ikke så meget det faktum at serierne giver seeren oplysning og indsigt i andre kulturer og områder på en letfordøjelig og populær måde, der er væsentligt. Det er derimod vigtigt at udvikle forståelsesrammer for demokratiske og kulturelle værdier af henholdsvis turisme, forbrugskultur og medieunderholdning som sådan. Artiklen peger afslutningsvis på forskellige former for globale og markedskulturelle vidensmatricer som rejseserierne repræsenterer

Compression forces used in the Norwegian Breast Cancer Screening Program

Objectives: Compression is used in mammography to reduce breast thickness, which is claimed to improve image quality and reduce radiation dose. In the Norwegian Breast Cancer Screening Program (NBCSP), the recommended range of compression force for full field digital mammography is 11-18 kg (108-177 Newton [N]). This is the first study to investigate the compression force used in the program. Methods: The study included information from 17,951 randomly selected women screened with FFDM at 14 breast centres in the NBCSP, January-March 2014. We investigated the applied compression force on left breast in craniocaudal (CC) and mediolateral oblique (MLO) view for breast centres, mammography machines within the breast centres and for the radiographers. Results: The mean compression force for all mammograms in the study was 116N and ranged from 91 to 147N between the breast centres. The variation in compression force was wider between the breast centres than between mammography machines (range 137-155N) and radiographers (95-143N) within one breast centre. Approximately 59% of the mammograms in the study complied with the recommended range of compression force. Conclusions: A wide variation in applied compression force was observed between the breast centres in the NBCSP. This variation indicates a need for evidence-based recommendations for compression force aimed at optimizing the image quality and individualising breast compression. Advances in knowledge: There was a wide variation in applied compression force between the breast centres in the NBCSP. The variation was wider between the breast centres than between mammography machines and radiographers within one breast centre

Tegnspråk i musikken: Soundpainting som improvisatorisk-kompositorisk verktøy

Sammendrag I denne avhandlingen har jeg studert tegnspråket Soundpainting, som ble skapt midt på 1970-tallet i New York, av den amerikanske jazz/ avantgarde-musikeren Walter Thompson. Jeg har sett på hva som var bakgrunnen for at Thompson bygde opp dette tegnspråket og hvilken ideologi som har preget det-med blant annet postmodernistiske tanker om hverdagslighet og ironi og «tverrkunstnerlige» ideer om å knytte musikk, dans, skuespillerutøvelse og visuelle kunstformer nærmere hverandre. Et spennende trekk ved Soundpainting er at det kan brukes i ulike sammenhenger, enten det er snakk om rene Soundpainting-performances, eller Soundpainting brukt som «ingrediens» i andre kunst- eller kulturuttrykk- og enten man befinner seg på en scene eller f.eks. i et klasserom. Og det var særlig i forhold til det sistnevnte jeg ville vurdere Soundpainting: Hvordan ville det oppleves å lære seg dette tegnspråket for musikkstudentene ved vår høgskole, og bruke det sammen med elever og praksislærere i grunnskolen og kulturskolen, gjennom deres praksisperioder? Jeg ønsket bl.a. å finne ut hvilke muligheter tegnspråket kan gi, særlig sett i forhold til improvisasjonsfeltet, ettersom jeg mener vi trenger flere verktøy for å jobbe med improvisasjon, spontanitet og kreativitet på det pedagogisk/utøvende feltet. Men jeg ville også se på hvilke musikalske, kommunikative og didaktiske utfordringer man møter når musikken skal skapes ut ifra tegn som gis av en ensembleleder, en såkalt Soundpainter, og hvor tegn og musikk skal utvikles og «videreforhandles» i et ensemble. Jeg ønsket også å se Soundpainting i forhold til ulik perspektivering av hva musikk er- med bl.a. utgangspunkt i spørsmål jeg har fått fra publikum etter egne Soundpainting-opptredener, som bl.a.: Soundpainting kan vel ikke kalles musikk? - og: Er Soundpainting en egen sjanger? Dette ville jeg se i sammenheng med hvordan vi er «oppdratt» til å forstå og oppleve musikk, særlig vurdert ut ifra noen av de paradigmene som har vært rådende innenfor den vestlige musikken de seneste århundrene- hvor enkelte parametere i musikken ikke bare har vært musikalsk bærende, men også styrt «definisjonsmakten» av hva musikk (og særlig hva god musikk) er. Jeg ønsket også å se og drøfte Soundpainting gjennom andre tegnspåk eller tegnsystemer som er relevante «sparrings-partnere», fortrinnsvis Conduction, Cobra og Oh, Pierre!- hvor jeg også ville gjøre komparative analyser- og likedan drøfte det nære forholdet man opplever i Soundpainting mellom improvisasjon, komponering og performance. Forskningsmetodologisk befinner jeg meg i denne monografien i spennet mellom, hermeneutikk, fenomenologi og postmodernisme, samt en metodologi som retter seg mot å bruke kunsten i forskningen (eller å forske på og med kunsten), nemlig arts-based research og A/r/tography: I artsbased research forsøker man å utnytte kunsten og forskningens ulike, men også komplementære styrker, og i A/r/tography, forsøker man å ivareta et mer holistisk perspektiv som skal gi rom for både pedagogen, forskeren og kunstneren i forskningsarbeidet.Summary This dissertation is about the sign-language, Soundpainting, which was created in the middle of the 1970s in New York, by the American jazz/avantgarde-musician Walter Thompson. I wanted to find the reason why Thompson made this sign language and understand the ideology characterizing itfrom a postmodern focus on "everyday life" and irony, and interdisciplinary ideas about linking music, dance, acting and visual art forms closer together. Soundpainting can be used in different contexts, whether your're talking about "pure" Soundpainting-performances, or Soundpainting used as an "ingredience" in different music-settings, or together with other disciplines of art- whether you are performing on a stage or for instance in a classroom. And it was particularly with regard to the latter aspect I would consider Soundpainting: How would it be to learn this sign language for the music students at our university-college, and how would they experience using it during their practice periods, together with pupils and practice-teachers in primary school and in Music & Art-school? I wanted to find out what possibilities this sign language can give us, particularly related to the field of improvisation, because of the lack of "didactic tools" in working with improvisation, spontaneity and creativity in the educational/performative field. But I would also focus on the musical, communicative and didactical challenges we meet when music shall be created on the basis of gestures given by a "conductor", called a Soundpainter- and then developed and "negotiated" in an ensemble. I also wanted to see Soundpainting related to different perspectives of what music is- especially connected to some questions I have received from the audience after some of my Soundpaintingperformances, like: Soundpainting may well not be called music? - and: Is Soundpainting a special genre? These questions I wanted to see in the context of how we are "raised" to understand and experience music, especially considering some of the paradigms that have dominated western music for some hundred years- where certain musical parameters not only have defined what is music, but have also "decided" what is good music. I also wanted to discuss Soundpainting through other sign-systems that are relevant "sparring partners", primarily Conduction, Cobra and Oh, Pierre! - and here I would make a comparative analysis- and likewise discuss the close connection between improvisation, composition and performance. Methodologically I will be in a phenomenological-hermeneutic and post-modern tradition, but I will also use perspectives from Arts Based Research, that wants to see art and research "complementary", and A/r/tography, that seeks an holistic thinking, which include both an Artist-, Researcher- and Teacher-perspective