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1.	Enquist, Henrik, et al. (författare) Konsten genomskådad? Forskning, Reflektion, Utveckling 2004 Rapport (övrigt vetenskapligt/konstnärligt)
2.	Koch, Markus, et al. (författare) Frequency of breaks, amount of muscular rest, and sustained muscle activity related to neck pain in a pooled dataset 2024 Ingår i: PLoS ONE. - 1932-6203. ; 19:6, s. 1-22 Tidskriftsartikel (refereegranskat)abstract BACKGROUND: Neck pain remains a persistent challenge in modern society and is frequently encountered across a wide range of occupations, particularly those involving repetitive and monotonous tasks. It might be expected that patterns of trapezius muscle activity at work, characterized by few breaks and prolonged periods of sustained muscle activity, are linked to neck pain. However, previous cross-sectional studies have generally failed to establish a definitive association. While some longitudinal studies have suggested that extended periods of heightened muscle activity could be a risk factor for neck pain, these findings often relied on limited participant numbers or specific professional groups. This study aimed to investigate the relationship between trapezius muscle activity and neck pain by pooling data from seven Scandinavian research institutes encompassing a diverse range of occupational backgrounds.METHODS: Electromyographic (EMG) data for the upper trapezius muscle, collected during working hours, were coupled with questionnaire responses pertaining to neck pain, individual characteristics, and potential confounding variables for a total of 731 subjects. Additionally, longitudinal data from 258 subjects were available. The various EMG datasets were consolidated into a standardized format, and efforts were made to harmonize inquiries about neck pain. Regression analyses, adjusting for sex and height, were conducted to explore the associations between muscle activity variables and neck pain. An exposure index was devised to quantify the cumulative neck load experienced during working hours and to differentiate between various occupational categories.RESULTS: The cross-sectional data displayed a distinct pattern characterized by positive associations for brief periods of sustained muscle activity (SUMA) and negative associations for prolonged SUMA-periods and neck pain. The longitudinal data exhibited a contrasting trend, although it was not as pronounced as the cross-sectional findings. When employing the exposure index, notable differences in cumulative muscle load emerged among occupational groups, and positive associations with longitudinal neck pain were identified.DISCUSSION: The results suggest that individuals with neck pain experience higher cumulative workloads and extended periods of muscle activity over the long term. In the short term, they appear to compensate by taking frequent short breaks, resulting in a lower cumulative workload. Regardless of their occupation, it is crucial to distribute work breaks throughout the workday to ensure that the cumulative load remains manageable.
3.	Zalden, Peter, et al. (författare) Femtosecond x-ray diffraction reveals a liquid–liquid phase transition in phase-change materials 2019 Ingår i: Science. - Washington, DC : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 364:6445, s. 1062-1067 Tidskriftsartikel (refereegranskat)abstract In phase-change memory devices, a material is cycled between glassy and crystalline states. The highly temperature-dependent kinetics of its crystallization process enables application in memory technology, but the transition has not been resolved on an atomic scale. Using femtosecond x-ray diffraction and ab initio computer simulations, we determined the time-dependent pair-correlation function of phase-change materials throughout the melt-quenching and crystallization process. We found a liquid–liquid phase transition in the phase-change materials Ag4In3Sb67Te26 and Ge15Sb85 at 660 and 610 kelvin, respectively. The transition is predominantly caused by the onset of Peierls distortions, the amplitude of which correlates with an increase of the apparent activation energy of diffusivity. This reveals a relationship between atomic structure and kinetics, enabling a systematic optimization of the memory-switching kinetics.
4.	Allaf Navirian, Hengameh, et al. (författare) Acoustically driven ferroelastic domain switching observed by time-resolved x-ray diffraction 2010 Ingår i: Physical Review B (Condensed Matter and Materials Physics). - 1098-0121. ; 81:2 Tidskriftsartikel (refereegranskat)abstract Domain polarization switching in potassium dihydrogen phosphate (KH2PO4, KDP) induced by a propagating strain wave has been observed with time-resolved x-ray diffraction. A pulsed electric field with amplitude of 6 kV/cm and duration of 1 mu s was applied along the crystallographic c axis. The field-induced strain waves emanating from the sample surfaces are the result of the converse piezoelectric effect. In the center of the probed surface two waves interfered constructively inducing ferroelastic domain switching, in the absence of an external electric field, at a delay of 3 mu s, corresponding to acoustic propagation at a velocity found to be 1500 m/s.
5.	Allaf Navirian, Hengameh, et al. (författare) Repetitive ultrafast melting of InSb as an x-ray timing diagnostic 2008 Ingår i: Applied Physics Reviews. - : AIP Publishing. - 1931-9401. ; 103:10, s. 6-103510 Tidskriftsartikel (refereegranskat)abstract We have demonstrated the possibility of using repetitive ultrafast melting of InSb as a timing diagnostic in connection with visible-light pump/x-ray probe measurements at high-repetition-rate x-ray facilities. Although the sample was molten and regrown approximately 1x10(6) times, a distinct reduction in time-resolved x-ray reflectivity could be observed using a streak camera with a time resolution of 2.5 ps. The time-resolved x-ray reflectivity displayed this distinct decrease despite the fact that the average reflectivity of the sample had fallen to approximately 50% of its original value due to accumulated damage from the prolonged laser exposure. The topography of the laser-exposed sample was mapped using an optical microscope, a stylus profilometer, photoelectron microscopy, and a scanning tunneling microscope. Although the surface of the sample is not flat following prolonged exposure at laser fluences above 15 mJ/cm(2), the atomic scale structure regrows, and thus, regenerates the sample on a nanosecond timescale. In the fluence range between 15 and 25 mJ/cm(2), the laser power is sufficient to melt the sample, while regrowth occurs with a sufficiently good structure to allow the extraction of timing information via ultrafast time-resolved x-ray measurements. This can be applied for timing purposes at synchrotron radiation and x-ray free-electron laser facilities. It is also noteworthy that we were able to reproduce the fluence dependencies of melting depth and disordering time previously obtained in single-shot, nonthermal melting experiments with higher temporal resolution.
6.	Arvidsson, Inger, et al. (författare) Action Levels for the Prevention of Work-Related Musculoskeletal Disorders in the Neck and Upper Extremities : A Proposal 2021 Ingår i: Annals of Work Exposures and Health. - : Oxford University Press (OUP). - 2398-7308 .- 2398-7316. ; 65:7, s. 741-747 Tidskriftsartikel (refereegranskat)abstract There are several well-known risk factors for work-related musculoskeletal disorders (MSDs). Despite this knowledge, too many people still work in harmful conditions. The absence of occupational exposure limits (OELs) for physical workload impedes both supervision and preventive work. To prevent myalgia, tendon disorders, and nerve entrapments in the upper musculoskeletal system, we propose action levels concerning work postures, movement velocities and muscular loads recorded by wearable equipment. As an example, we propose that wrist velocity should not exceed 20°/s as a median over a working day. This has the potential to reduce the prevalence of carpal tunnel syndrome (CTS) in highly exposed male occupational groups by 93%. By reducing upper arm velocity in highly exposed female groups to the suggested action level 60°/s, the prevalence of pronounced neck/shoulder myalgia with clinical findings (tension neck syndrome) could be reduced by 22%. Furthermore, we propose several other action levels for the physical workload. Our ambition is to start a discussion concerning limits for physical workload, with the long-term goal that OELs shall be introduced in legislation. Obviously, the specific values of the proposed action levels can, and should, be discussed. We hope that quantitative measurements, combined with action levels, will become an integral part of systematic occupational health efforts, enabling reduction and prevention of work-related MSDs.
7.	Arvidsson, Inger, et al. (författare) Reply to Letter to the Editor, by Mikael Forsman, Xuelong Fan, Ida-Märta Rhen and Carl Mikael Lind 2022 Ingår i: Annals of Work Exposures and Health. - : Oxford University Press (OUP). - 2398-7308 .- 2398-7316. ; 66:1, s. 132-132 Tidskriftsartikel (refereegranskat)
8.	Burza, Matthias, et al. (författare) Dispersion and monochromatization of x-rays using a beryllium prism 2015 Ingår i: Optics Express. - 1094-4087. ; 23:2, s. 620-627 Tidskriftsartikel (refereegranskat)abstract We demonstrate experimentally and numerically that an x-ray prism made of beryllium can be used to disperse and monochromatize x-rays. A polished beryllium cuboid was employed as refractive and dispersive optics. The results of a proof-of-principle experiment and methods of performance optimization are presented. The spatial separation of undulator harmonics and their subsequent selection using a slit are described. A numerical study, assuming realistic beam and beamline parameters, suggests that undulator harmonics can be spatially separated in the range from 3 keV to beyond 20 keV, while maintaining throughput above 50%. Refractive optics is particularly suitable for low-repetition-rate sources such as free-electron lasers and other LINAC-based short-pulse sources. (C) 2015 Optical Society of America
9.	Dahlqvist, Camilla, et al. (författare) Arbetsbelastning vid städning av hotellrum 2017 Rapport (övrigt vetenskapligt/konstnärligt)abstract Enligt Arbetsmiljöverkets rapport ”Arbetsmiljön 2013” har 40 procent av alla hotell- och kontorsstädare ont i nacke, rygg, axlar eller armar varje vecka. 60 procent av dem känner sig uttröttade i kroppen. Arbets- och miljömedicin (AMM) Syd har tagit fram åtgärdsnivåer för ett antal belastningsmått, ”AMM Syds åtgärdsnivåer för ergonomisk belastning”, och om man överstiger dessa, anser vi att risken för belastningsskada är stor. Vi har studerat hotellrumsstädares belastning och jämfört med våra åtgärdsnivåer.Vi mätte den fysiska arbetsbelastningen hos fjorton kvinnliga hotellrumsstädare under en vanlig arbetsdag, på en deltagare åt gången. De arbetade på sju olika hotell i södra Sverige. Några var anställda av städföretag och några direkt av hotellen.Vi fann att hotellrumsstädare har en väldigt hög arbetsbelastning i övre delen av kroppen, både vad gäller rörelsehastighet, arbetsställningar och muskelansträngning (se Tabell på sid 3). Samtliga deltagare hade för hög rörelsehastighet i överarm och handled och för lite vila i underarmens muskler i jämförelse med våra åtgärdsnivåer. Även vad gäller framåtböjningen av huvudet, överarmens arbetsställning och underarmens muskelbelastning fann vi för höga nivåer. Hotellrumsstädning överskrider nio av våra elva åtgärdsnivåer för ergonomisk belastning. Detta betyder att hotellrumsstädare har en väldigt hög risk att drabbas av belastningsskador.RekommendationerFör att minska risken för belastningsskador bland hotellrumsstädare måste arbetstempot sänkas, genom att minska antalet rum som ingår i en hotellrumsstädares arbetsdag.Personalen bör erbjudas regelbundna medicinska kontroller avseende ergonomiskt belastande arbete så att man tidigt sätter in åtgärder för den arbetstagare eller grupp av arbetstagare som är på väg att utveckla skada i muskler och/eller leder. Arbetsplatsen rekommenderas att ha företagshälsovård knuten till sig, som kan genomföra de medicinska kontrollerna och som kontinuerligt gör riskbedömningar av arbetet. De bör också ha som uppgift att utbilda städpersonalen i ergonomi.
10.	Dahlqvist, Camilla, et al. (författare) Arbetsbelastning vid städning av hotellrum 2017 Rapport (refereegranskat)
11.	Dahlqvist, Camilla, et al. (författare) Mätning av arbetsbelastning för höger överarm vid kontorsstädning 2016 Rapport (övrigt vetenskapligt/konstnärligt)
12.	Dahlqvist, Camilla, et al. (författare) Self-recordings of upper arm elevation during cleaning - comparison between analyses using a simplified reference posture and a standard reference posture 2018 Ingår i: BMC Musculoskeletal Disorders. - : BMC. - 1471-2474. ; 19 Tidskriftsartikel (refereegranskat)abstract Background To reduce ergonomic risk factors in terms of awkward and constrained postures and high velocities, it is important to perform adequate risk assessments. Technical methods provide objective measures of physical workload. These methods have so far mainly been used by researchers. However, if written instructions how to apply the sensors and how to adopt the reference posture are provided, together with triaxial accelerometers, it may be possible for employees to record their own physical workload. The exposure in terms of e.g. upper arm elevations could then easily be assessed for all workers in a workplace. The main aims of this study were: 1) to compare analyses for self-recording of upper arm elevation during work using a simplified reference posture versus using a standard reference posture, and 2) to compare the two reference postures.MethodsTwenty-eight cleaners attached an accelerometer to their dominant upper arm and adopted a simplified reference according to a written instruction. They were thereafter instructed by a researcher to adopt a standard reference. Upper arm elevations were recorded for 2 or 3 days. Each recording was analysed twice; relative to the simplified reference posture and relative to the standard reference posture. The group means of the differences in recorded upper arm elevations between simplified and standard reference analyses were assessed using Wilcoxon signed ranks test. Furthermore, we calculated the group mean of the differences between the simplified reference posture and the standard reference posture.ResultsFor arm elevation during work (50(th) percentile), the group mean of the differences between the two analyses was 0.2 degrees (range-7 - 10 degrees). The group mean of the differences between the two references was 9 degrees (range 1-21 degrees). The subjects were able to follow the instructions in the protocol and performed self-recording of upper arm elevation and velocity.ConclusionsThe small difference between the two analyses indicates that recordings performed by employees themselves are comparable, on a group level, with those performed by researchers. Self-recordings in combination with action levels would provide employers with a method for risk assessment as a solid basis for prevention of work-related musculoskeletal disorders.
13.	Dahlqvist, Camilla, et al. (författare) The effect of two types of maximal voluntary contraction and two electrode positions in field recordings of forearm extensor muscle activity during hotel room cleaning 2020 Ingår i: International Journal of Occupational Safety and Ergonomics. - : Informa UK Limited. - 1080-3548 .- 2376-9130. ; 26:3, s. 595-602 Tidskriftsartikel (refereegranskat)abstract Purpose. This study aimed to investigate the effects of using hand grip or resisted wrist extension as the reference contraction, and two electrode positions, on field recordings of forearm extensor muscle activity. Materials and methods. Right forearm extensor muscle activity was recorded using two electrode pairs (over the most prominent part (position 2) and proximal to that (position 1)) during one working day in 13 female hotel housekeepers. Each subject performed the two maximal voluntary contractions (MVCs), and the electrical activity obtained during these (maximal voluntary electrical activity (MVE)) was used for normalization. Each set of recordings was analysed twice, once using hand grip as the MVC and once using resisted wrist extension. Results. Resisted wrist extension showed a higher group mean MVE than hand grip. Position 2 had higher correlation between MVE and force during the MVCs. The workload during cleaning was lower when using resisted wrist extension as reference than when using hand grip (24%MVE vs 46%MVE; p = 0.002 at position 2) for the 90th percentile. The workload (99th percentile) was overestimated in two subjects when using hand grip as reference. Conclusions. Problems associated with poorly activated forearm extensors can be overcome by using resisted wrist extension as reference.
14.	Enquist, Henrik (författare) A socio-material ecology of the distributed self 2008 Ingår i: Design Philosophy Papers. - 1448-7136. ; :2 Tidskriftsartikel (refereegranskat)abstract When distributed to different artefacts, the self appears in a multitude of shapes, characterized not only by its materiality but also by the necessity to preserve at least an illusion of a core self. The experience of a continuous evolution of these overlapping “selves”, many of which are materialized together with others’ overlapping selves, cannot be captured by traditional design approaches, nor can ethical aspects and conflicts of the right to express yourself through artefacts. This article, with its empirical basis in an interdisciplinary EU funded project, PalCom, is an attempt to test both ecological concepts and relationships and sociological (actants, actor-network-theory) ones. No meaningful separations are observed between the human ecology and sociology and the artefactual ones. Instead, it is the whole system of people, practices, values, and technologies in a particular situatedness that is meaningful to pinpoint and elaborate. In this text, the notion of the distributed self will be discussed. By this I mean the way artefacts are included in the study of an individual. There are many things to be considered when thinking of the socio-materiality of this distributed self. Here, two different approaches are tested, separately and intertwined: a sociological and an ecological.
15.	Enquist, Henrik (författare) Alternative visualizations in medicine 2005 Ingår i: Experiments in Art and Technology. - 9171040129 ; 4 Bokkapitel (övrigt vetenskapligt/konstnärligt)
16.	Enquist, Henrik (författare) Bridging the gap between clinical and patient-provided images 2005 Ingår i: The First Conference in Visual Literacy. Konferensbidrag (refereegranskat)abstract I will be reporting here on how a group of artists and designers and a group of patients approached the task of visualising the meaning of specific medical diagnoses without recourse to traditional medical imagery. The purpose was to investigate how people relate to images produced in healthcare and how alternative visual aids might complement printed and verbal communications between doctor and patient. One fundamental concern of this study was to evaluate the influence and effect images have on patients´experience and knowledge of their personal health. The study was carried out to collect material for further research and ultimately for the development of visualisation tools, methods and objects.
17.	Enquist, Henrik, et al. (författare) Bridging the gap between clinical and patient-provided images 2007 Ingår i: Visual Literacy. - 9780415958103 ; , s. 145-163 Bokkapitel (övrigt vetenskapligt/konstnärligt)
18.	Enquist, Henrik (författare) Emotional images in medicine 2004 Ingår i: Fourth International Conference on Design and Emotion. Konferensbidrag (refereegranskat)abstract This paper introduces ideas for future research that explore non-diagnostic uses of images in medicine. The dynamics are studied from a subjective and emotional perspective, a standpoint common in art and design but rarely considered relevant in academic medicine and science. The fundamental aim of the project is to study how images can influence and alter the afflicted individuals’ experiences of body and health, and contribute to enhanced feelings of well-being, participation and joy in everyday life. There is a growing public interest in medical images, both in popular science but also in the private and personal spheres, one example being the controversial use of foetal keepsake videos as recreational images. There seems to be an increasing need for people being able to see, and consequently know, more about themselves and their medical situations. Emotionally and individually designed images will probably play an important role in future healthcare, both as an integrated part of regular medicine and as private emancipative artefacts. A series of design criteria are discussed concerning the format of the images, i.e. original or modified clinical images and individually designed images based on personal demands and needs. Different modes of use are discussed, ranging from informational, educational and communicative to emotional and recreational, with the experiences of well-being and emancipation as common denominators. An outline for future research is presented discussing potential user groups, functional specifications including accessibility and flexibility as well as questions of ethics, economics, intellectual property rights and confidentiality.
19.	Enquist, Henrik, et al. (författare) FemtoMAX - An X-ray beamline for structural dynamics at the short-pulse facility of MAX IV 2018 Ingår i: Journal of Synchrotron Radiation. - 0909-0495. ; 25:2, s. 570-579 Tidskriftsartikel (refereegranskat)abstract The FemtoMAX beamline facilitates studies of the structural dynamics of materials. Such studies are of fundamental importance for key scientific problems related to programming materials using light, enabling new storage media and new manufacturing techniques, obtaining sustainable energy by mimicking photosynthesis, and gleaning insights into chemical and biological functional dynamics. The FemtoMAX beamline utilizes the MAX IV linear accelerator as an electron source. The photon bursts have a pulse length of 100fs, which is on the timescale of molecular vibrations, and have wavelengths matching interatomic distances (Å). The uniqueness of the beamline has called for special beamline components. This paper presents the beamline design including ultrasensitive X-ray beam-position monitors based on thin Ce:YAG screens, efficient harmonic separators and novel timing tools.The FemtoMAX beamline facilitates studies of the structural dynamics of materials on the femtosecond timescale. The first commissioning results are presented.
20.	Enquist, Henrik, et al. (författare) From Idea to Use: Lessons Learned From a Participatory ICT Healthcare Case Study 2011 Ingår i: Smart Healthcare Applications and Services: Developments and Practices: Developments and Practices. - : IGI Global. - 9781609601829 - 9781609601805 ; , s. 75-91 Bokkapitel (övrigt vetenskapligt/konstnärligt)
21.	Enquist, Henrik, et al. (författare) Interaction Ecologies 2007 Ingår i: Workshop proceedings from the Fifth International Conference on Pervasive Computing. Konferensbidrag (refereegranskat)abstract In this paper we present one approach to understand palpability from the perspective of eco-systems of palpable devices. We will introduce the notion of Palpable Interaction Ecology that particular focus upon the properties that emerge from the interaction between people, their practices and palpable devices. This approach is derived from research into the use of pervasive healthcare services that support women during their pregnancies. This is a situation where information is currently distributed among many parties. This makes it very difficult for the pregnant woman to assess her situation. To address these issues we have designed digital artifacts that support the pregnant women’s information management as well as facilitating the interaction with healthcare providers. The concepts have been examined using workshops, user scenarios and low-fidelity prototyping through active participation of both healthcare personnel and pregnant women. The results of this work suggest that the proposed concepts have the potential to be incorporated both in healthcare and in the household routines if particular focus is given to understanding shifting needs and uses over time. Visibility and invisibility, construction and de-construction, and supporting people in making computing palpable are among the important challenges facing the Palcom Project. Originating from the biology field, an ecology is often used to illustrate relations between an organism and the surrounding environment. We have in our case found a similar need to describe diversity in use situation and the interaction between invisible and visible information as well as the interaction of construction and de-construction of devices and data. A Palpable interaction ecology incorporates both a pervasive computing presence and the ability to add and subtract devices and data as desired. The ecology notion offers here an analysis unit of properties that emerge from the interaction between people and palpable services and devices. It is argued that by study how these ecologies emerged we could create a new understanding of palpable interaction and the making of palpable computing.
22.	Enquist, Henrik, et al. (författare) Intuition in Design and Emotion – Transforming raw data into conclusions, a meta-analysis of the 2006 Design and Emotion conference papers. 2008 Ingår i: [Host publication title missing]. - 9789881748928 Konferensbidrag (refereegranskat)abstract In any research field the transformation of raw data into conclusions is a critical phase, necessitating a systematic approach. The basic question is: How can I as a (design) researcher corroborate my conclusions? This paper is based on a study of the analytical/interpretative portion of papers published in the Proceedings of the 2006 Design & Emotion Conference. We investigate how the authors present the interpretative process in their papers, such as using specific methods for interpretation and analysis. It became obvious that there were few specific methods for interpretation mentioned in the Conference papers studied, though there was a wide range of methodological approaches from theoretical and statistical to purely qualitative. Notably, most papers did not mention any method at all. The issue of interpretation is certainly not new, but in the light of the topic of design for emotions, design (research) by emotions or intuition should be discussed.
23.	Enquist, Henrik, et al. (författare) Large acoustic transients induced by non-thermal melting of InSb 2007 Ingår i: Physical Review Letters. - 1079-7114. ; 98 Tidskriftsartikel (refereegranskat)abstract We have observed large-amplitude strain waves following a rapid change in density of InSb due to nonthermal melting. The strain has been measured in real time via time-resolved x-ray diffraction, with a temporal resolution better than 2 ps. The change from the solid to liquid density of the surface layer launches a high-amplitude strain wave into the crystalline material below. This induces an effective plane rotation in the asymmetrically cut crystal leading to deflection of the diffracted beam. The uniform strain in the layer below the molten layer is 2.0(±0.2)%. A strain of this magnitude develops within 5 ps of the incident pulse showing that the liquid has reached the equilibrium density within this time frame. Both the strain amplitude and the depth of the strained material in the solid can be explained by assuming a reduction in the speed of sound in the nonequilibrium liquid compared to measured equilibrium values.
24.	Enquist, Henrik (författare) Mina medicinska bilder 2004 Rapport (övrigt vetenskapligt/konstnärligt)abstract Medicin, sett som ett epistemologiskt system, har delat upp kunskapen om människan och hennes sjukdomar i ett allt större antal mindre delar. Detta har visat sig vara både ett effektivt och nödvändigt sätt att skapa och använda kunskap. Det är givetvis bå
25.	Enquist, Henrik (författare) Narcissus's new mirror: Body images and meaning 2007 Ingår i: Crossings (Dublin): ): electronic journal of art and technology. - 1649-0460. ; 5:1 Tidskriftsartikel (refereegranskat)abstract The wish to see beyond the horizon of the human biological eye is one of the major driving forces in the development of medical imaging technology. This essay discusses the implications technology has on the ability to see, and consequently know, more about the body. Further, the potential of merging art, rehabilitation engineering and medicine to develop and use images specifically designed to create meaning for the afflicted individual is proposed as a future research topic. The key question is how alternative (i.e., non-clinical) perspectives can result in different experiences of well-being, or even improve the health of the individual. There are two main aspects of this future research: one practical and technological, concerned with the tools and methods to be used, the other an epistemological venture, aimed at disseminating knowledge and understanding of visual communication in a medical context.
26.	Enquist, Henrik (författare) Pictures in medicine: Their use in patient centered diagnosis, treatment and feedback 2004 Rapport (övrigt vetenskapligt/konstnärligt)abstract Medicine, seen as an epistemological system, has broken down the knowledge of humans and their diseases into a growing number of smaller components. This has proven to be an effective and necessary way of creating and using knowledge. It is, of course, ne
27.	Enquist, Henrik (författare) Självbiografiskt skapande 2007 Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract Licentiatuppsatsen handlar om självbiografiskt skapande och tar utgångspunkt i tre huvudspår. Det första är den egna positionens roll och hur man skulle kunna argumentera för en individuell objektivitet. Det andra behandlar medieringen av jaget och
28.	Enquist, Henrik (författare) Studies of Phonons and Phase Transitions by Time-Resolved X-ray Diffraction 2009 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract When light is used to study structures, the wavelength limits the size of the details that can be resolved. Visible light can be used to investigate structures as small as a micrometre in size. To study smaller structures a shorter wavelength is required. The wavelength of hard X-ray radiation is much shorter than that of visible light, and is comparable to the distance between atoms in solids and liquids, which is a few tenths of a nanometre. X-ray diffraction can thus be used to study structures on the atomic scale, and by conducting the measurements with high time resolution the atomic motion can be mapped. The absorption of intense ultrashort laser pulses in solid materials can trigger a multitude of processes. Heating arising from the deposition of energy leads to rapid expansion, creating coherently excited phonons. The properties of the material are changed by the large number of excited carriers, for instance enhancement of the heat conductivity. Very intense pulses may even induce melting. Time-resolved X-ray diffraction can then be used to directly measure the changes in the structure. As the material cools down the molten material solidifies, and the surface can develop sub-micrometre periodic structures. Not only laser pulses induce structural changes. Electric pulses can generate largeamplitude acoustic pulses in piezoelectric materials, which can then trigger phase transitions between different solid structures. Using time-resolved X-ray diffraction it is possible to follow the transition in real time. The work described in this thesis has been focused mainly on experimental studies of structural dynamics with picosecond time resolution. The results obtained have, among other things, helped in the understanding of the various processes involved in the melting and subsequent regrowth of semiconductors, as well as the dynamics of the photocarriers following intense laser excitation.
29.	Enquist, Henrik, et al. (författare) Subpicosecond hard x-ray streak camera using single-photon counting. 2010 Ingår i: Optics Letters. - 1539-4794. ; 35:19, s. 3219-3221 Tidskriftsartikel (refereegranskat)abstract We have developed and characterized a hard x-ray accumulating streak camera that achieves subpicosecond time resolution by using single-photon counting. A high repetition rate of 2 kHz was achieved by use of a readout camera with built-in image processing capabilities. The effects of sweep jitter were removed by using a UV timing reference. The use of single-photon counting allows the camera to reach a high quantum efficiency by not limiting the divergence of the photoelectrons.
30.	Enquist, Henrik (författare) The I in Design 2009 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract This thesis describes the relations between objects, practices, and individuals. The main objective is to explore the role of artefacts in user-centred participatory design research, specifically for expressing and communicating personal experiences and creating meaning. In a broad sense I draw on experiences from three practices in order to define the scope of the thesis. The first is practice-led research, the second is design research specifically in the user-centred and participatory design traditions, and the third is concerned with the ways lay persons in general express themselves by and through objects and technology. The focus will be on the exchange of knowledge and experiences between two individuals: the researcher and the informant. One issue of interest is how communication can be made possible. Another is the use of artefacts for personal expression. A third is the constant balancing act when using the experiences and knowledge of a single or a few informants in design research. The first half of the thesis is based on two design cases. Their common denominator is the exploration of how people can introduce their personal perspectives on their health situation into the medical context through the use of expressive artefacts. The first is a study of personal visualisations of experienced health (papers I, II). A future practice of routinely creating and using (instrumental) images based on emotions, meaning and subjectivity in rehabilitation and healthcare is proposed. The second case describes the development of a personal digital device, the Memory Stone used for storing and sharing personal and clinical information (papers III, IV). The case involves pregnant women but the device can be used wherever there is an interest in keeping personal diaries, handling medical information in novels ways, and interacting with information technology at home and in healthcare. The second half of the thesis is an explorative venture grounded partly in the empirical work described in the first half, partly in extensive reading of literature from a wide range of disciplines. Three main areas have been included to discuss the relationship between humans, objects, technology, and self-narratives: a technology of the self (the self as image and data), a science of the self (autoethnography), and autobiographies. The intention is to set the stage for a critical and productive discussion on how the notion of autobiographic practice can inform and enrich design research methodology.
31.	Enquist, Henrik, et al. (författare) The memory stone : a personal ICT device in health care 2008 Ingår i: ACM International Conference Proceeding Series. - New York, NY, USA : ACM. - 9781595937049 ; , s. 103-112 Konferensbidrag (refereegranskat)abstract New technology enables novel ways of sharing information between health care recipients and providers. In this study, however, we found that the medical information for pregnant women in Denmark is located in a number of different places, that midwives and doctors spend a considerable amount of time administrating data, and that consultations are felt to be rather inefficient. This paper describes these problems and some solutions. We explore the idea of providing each woman with a digital artifact, called the Memory Stone. The goal is to supply them with tools to collect and review clinical and personal information concerning their pregnancies. The paper discusses: (1) the user-centered methodology for development of a personal device for health care information, (2) the design and evaluation of prototypes, and (3) critical issues concerning the introduction of novel personal ICT in a health care setting. The main focus is on the experiences and interests of the individual pregnant woman in the study. Several insights were gained into more general pervasive health care issues, including technical and ethical ones as well as safety and security concerns.
32.	Enquist, Henrik (författare) Upplevelser av ett dubbelt medborgarskap: Metod och praktik. Texter om forskning och utvecklingsarbete inom det konstnärliga området. 2005 Ingår i: Årsbok 2005 om Konstnärligt FoU. Bokkapitel (övrigt vetenskapligt/konstnärligt)
33.	Enquist, Per-Anders, et al. (författare) Derivatives of 8-hydroxyquinoline-antibacterial agents that target intra- and extracellular Gram-negative pathogens 2012 Ingår i: Bioorganic & Medicinal Chemistry Letters. - : Elsevier. - 0960-894X .- 1464-3405. ; 22:10, s. 3550-3553 Tidskriftsartikel (refereegranskat)abstract Small molecule screening identified 5-nitro-7-((4-phenylpiperazine-1-yl-)methyl)quinolin-8-ol INP1750 as a putative inhibitor of type III secretion (T3S) in the Gram-negative pathogen Yersinia pseudotuberculosis. In this study we report structure-activity relationships for inhibition of T3S and show that the most potent compounds target both the extracellular bacterium Y. pseudotuberculosis and the intracellular pathogen Chlamydia trachomatis in cell-based infection models.
34.	Harb, Maher, et al. (författare) Picosecond dynamics of laser-induced strain in graphite 2011 Ingår i: Physical Review B (Condensed Matter and Materials Physics). - 1098-0121. ; 84:4 Tidskriftsartikel (refereegranskat)abstract We report on the use of grazing-incidence time-resolved x-ray diffraction to investigate the evolution of strain in natural graphite excited by femtosecond-laser pulses in the fluence range of 6-35 mJ/cm(2). Strains corresponding to up to similar to 2.8% c-axis expansion were observed. We show that the experimental data is in good agreement with calculations based on the Thomsen strain model in conjunction with dynamical diffraction theory. Furthermore we find no evidence of nonthermal lattice expansion as reported in recent ultrafast electron-diffraction studies of laser-excited graphite conducted under comparable excitation conditions.
35.	Harb, Maher, et al. (författare) The c-axis thermal conductivity of graphite film of nanometer thickness measured by time resolved X-ray diffraction 2012 Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 101:23 Tidskriftsartikel (refereegranskat)abstract We report on the use of time resolved X-ray diffraction to measure the dynamics of strain in laser-excited graphite film of nanometer thickness, obtained by chemical vapour deposition (CVD). Heat transport in the CVD film is simulated with a 1-dimensional heat diffusion model. We find the experimental data to be consistent with a c-axis thermal conductivity of similar to 0.7 Wm(-1) K-1. This value is four orders of magnitude lower than the thermal conductivity in-plane, confirming recent theoretical calculations of the thermal conductivity of multilayer graphene. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4769214]
36.	Holtermann, Andreas, et al. (författare) A practical guidance for assessments of sedentary behavior at work: A PEROSH initiative 2017 Ingår i: Applied Ergonomics. - : Elsevier BV. - 0003-6870 .- 1872-9126. ; 63, s. 41-52 Tidskriftsartikel (refereegranskat)abstract Sedentary behavior is defined as sitting or lying with low energy expenditure. Humans in industrialized societies spend an increasing amount of time in sedentary behaviors every day. This has been associated with detrimental health outcomes. Despite a growing interest in the health effects of sedentary behavior at work, associations remain unclear, plausibly due to poor and diverse methods for assessing sedentary behavior. Thus, good practice guidance for researchers and practitioners on how to assess occupational sedentary behavior are needed. The aim of this paper is to provide a practical guidance for practitioners and researchers on how to assess occupational sedentary behavior. Ambulatory systems for use in field applications (wearables) are a promising approach for sedentary behavior assessment. Many different small-size consumer wearables, with long battery life and high data storage capacity are commercially available today. However, no stand-alone commercial system is able to assess sedentary behavior in accordance with its definition. The present paper offers decision support for practitioners and researchers in selecting wearables and data collection strategies for their purpose of study on sedentary behavior. Valid and reliable assessment of occupational sedentary behavior is currently not easy. Several aspects need to be considered in the decision process on how to assess sedentary behavior. There is a need for development of a cheap and easily useable wearable for assessment of occupational sedentary behavior by researchers and practitioners
37.	Holtermann, Andreas, et al. (författare) Assessing sedentary behaviour at work with technical assessment systems 2017 Rapport (refereegranskat)abstract It is well documented that spending large amounts of time each day in sedentary behaviour is associated with increased risks of a variety of health impairments. The time engaged in sedentary behaviours is generally high in Europe, and has increased over recent decades during both work and leisure. This has resulted in considerable research and societal attention over the last decade.Sedentary behaviour in the workplace varies between occupations. It is high among office workers, and is likely to be high for job groups with lower education with constrained sittingbased working tasks like long-haul drivers and surveillance work in manufacturing. However, the question of whether spending large amounts of time in occupational sedentary behaviour is a causal risk factor for health impairments remains to be settled.An important reason for this could be the poor validity and reliability of many of the methods used to assess sedentary behaviour such as self-report and interviews. Another reason might be that the sedentary behaviour is often not measured in accordance with its proposed definition "any waking behaviour characterised by a low energy expenditure (≤1.5 METs) while in a sitting or reclining posture". Measurements of sedentary behaviour should therefore capture its two main components, namely posture and energy expenditure.Observational methods are also used to assess sedentary behaviour, but they are costly, time-consuming, and may lead to observational-bias. Measurements using wearable devices ("wearables") are thus recommended due to their objective nature, and their ability to be relatively low cost and to have little impact on the daily life of the participant.Numerous suitable small wearables, with long battery life and high data storage capacity, have become commercially available in recent years. However, none of the commercially available wearables can independently assess occupational sedentary behaviour in accordance with its definition (i.e. a sitting or lying posture with low energy expenditure). Therefore, deciding on how to assess sedentary behaviour is currently not easy.The wide variety of devices with the potential to assess sedentary behaviour is likely to leave practitioners and researchers wondering - "How can I choose the measurement system bestsuited to my aim, preferences, funding, and skills?" However, no practically useful guidance for researchers and practitioners exists on how to assess occupational sedentary behaviour.This report provides an overview of relevant technical systems and their general capabilities and gives examples of their appropriate use when assessing occupational sedentary behaviour. The report emphasises factors such as the target population, the need for accuracy, data accessibility, wearing comfort, expert knowledge for analyses, assessment duration, the number of participants needed, budget available, and the need for information on time patterns of sedentary and non-sedentary behaviour, including moderate and vigorous physical activity. Importantly, the need for assessing body posture, energy expenditure, or both, should be critically evaluated based on the work tasks undertaken by the target population and the aim of the project.The report highlights needs for developing of cheap, feasible wearables combining precise posture and energy assessments for a valid and reliable assessment of sedentary behaviour at work, which fulfils the current needs of both researchers and practitioners alike.
38.	Jurgilaitis, Andrius, et al. (författare) Measurements of light absorption efficiency in InSb nanowires 2014 Ingår i: Structural Dynamics. - : AIP Publishing. - 2329-7778. ; 1:1 Tidskriftsartikel (refereegranskat)abstract We report on measurements of the light absorption efficiency of InSb nanowires. The absorbed 70 fs light pulse generates carriers, which equilibrate with the lattice via electron-phonon coupling. The increase in lattice temperature is manifested as a strain that can be measured with X-ray diffraction. The diffracted X-ray signal from the excited sample was measured using a streak camera. The amount of absorbed light was deduced by comparing X-ray diffraction measurements with simulations. It was found that 3.0(6)% of the radiation incident on the sample was absorbed by the nanowires, which cover 2.5% of the sample. (C) 2013 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.
39.	Jurgilaitis, Andrius, et al. (författare) Time-Resolved X-ray Diffraction Investigation of the Modified Phonon Dispersion in InSb Nanowires 2014 Ingår i: Nano letters (Print). - Washington, DC : American Chemical Society (ACS). - 1530-6984 .- 1530-6992. ; 14:2, s. 541-546 Tidskriftsartikel (refereegranskat)abstract The modified phonon dispersion is of importance for understanding the origin of the reduced heat conductivity in nanowires. We have measured the phonon dispersion for 50 nm diameter InSb (111) nanowires using time-resolved X-ray diffraction. By comparing the sound speed of the bulk (3880 m/s) and that of a classical thin rod (3600 m/s) to our measurement (2880 m/s), we conclude that the origin of the reduced sound speed and thereby to the reduced heat conductivity is that the C44 elastic constant is reduced by 35% compared to the bulk material. © 2014 American Chemical Society.
40.	Jurgilaitis, Andrius, et al. (författare) Time resolved X-ray studies in semiconductor nanostructures 2012 Ingår i: 2012 Conference on Lasers and Electro-Optics (Cleo). - 9781557529336 Konferensbidrag (refereegranskat)abstract Time resolved X-ray diffraction has been used to study acoustic oscillations in InAs/Sb nanowires with diameters of 80 nm and 40 nm in order to determine the speed of sound in the wires.
41.	Jurgilaitis, Andrius, et al. (författare) X-ray diffraction from the ripple structures created by femtosecond laser pulses 2010 Ingår i: Applied Physics A: Materials Science & Processing. - : Springer Science and Business Media LLC. - 1432-0630. ; 100:1, s. 105-112 Tidskriftsartikel (refereegranskat)abstract In this paper, we present the investigation and characterization of the laser-induced surface structure on an asymmetrically cut InSb crystal. We describe diffraction from the ripple surface and present a theoretical model that can be used to simulate X-ray energy scans. The asymmetrically cut InSb sample was irradiated with short-pulse radiation centred at 800 nm, with fluences ranging from 10 to 80 mJ/cm(2). The irradiated sample surface profile was investigated using optical and atomic force microscopy. We have investigated how laser-induced ripples influence the possibility of studying repetitive melting of solids using X-ray diffraction. The main effects arise from variations in local asymmetry angles, which reduce the attenuation length and increase the X-ray diffraction efficiency.
42.	Jönsson, Bodil, et al. (författare) Design side by side 2006 Bok (övrigt vetenskapligt/konstnärligt)abstract The starting point for most of what is written here is people with disabilities. Situations of great difficulty need to be highly prioritized, for their own sake and also because that which first appears to be “special” sooner or later comes to benefit so
43.	Jönsson, Bodil, et al. (författare) Människonära design 2005 Bok (övrigt vetenskapligt/konstnärligt)abstract Det mesta i den här boken tar sin utgångspunkt i människor med funktionsnedsättningar. Situationer med stora svårigheter behöver en stark prioritering, både för sin egen del och för att det särskilda förr eller senare brukar komma det gemensamma till godo. Boken har två delar. Den första består av tio minst sagt spretiga kapitel som alla visar på att hur svår en situation än är, finns det alltid något man kan göra. Dessa kapitel är nog så innehållsrika men samtidigt lättlästa. De är helt enkelt avsedda att berätta sina historier, rakt upp och ner, varje kapitel för sig. Fullt så lättläst är inte del 2. I den försöker vi visa på teori- och metodbildning som kan underlätta, hålla samman och vidareutveckla. Den delen har också en rikhaltig referenslista för vidare studier.
44.	Jönsson, Bodil, et al. (författare) Situated research and design for everyday life 2004 Rapport (övrigt vetenskapligt/konstnärligt)abstract This paper elaborates theoretical and methodological aspects of design processes in a disability context and aims to relate them to other sciences. It particularly emphasizes situated aspects of research: the need for being there, with the users in their
45.	Jönsson, Bodil, et al. (författare) Situated research and design for everyday life 2005 Ingår i: Proceedings of Nordes, Nordic Design Research. Konferensbidrag (refereegranskat)abstract This paper presents examples of different aspects of design in a disability context with the aim of revealing some of its fundamentals. It particularly emphasizes situated aspects of research: the need for being there, with the users in their daily lives – where the action is.
46.	Locks, Francisco, et al. (författare) Biomechanical exposure of industrial workers – Influence of automation process 2018 Ingår i: International Journal of Industrial Ergonomics. - : Elsevier BV. - 0169-8141. ; 67, s. 41-52 Tidskriftsartikel (refereegranskat)abstract Automated processes in industry have been implemented in order to get higher production rates, but our knowledge about their effects on physical exposure of the workers is still limited. Muscular load, postures, and movements of the head, neck/shoulders, upper arms, and wrists were recorded in 19 operators from two different car clutch disc production lines (manual and semi-automated). Higher angular velocities of the head, upper back, and upper arms were found on the manual production line (on average 20% higher than the semi-automated). Upper trapezius, and forearm extensor rest (% time), as well as hand kept still (% time) were also higher on the manual production line. No difference was found regarding posture, muscular activities, and repetitiveness. The manual line had more rest, but more vigorous movements considering angular velocities. The semi-automated line, therefore, implied a higher production rate with lower angular velocities but fewer opportunities for rest than the manual line. While different physical exposures were found when comparing these two production lines with different levels of automation, the health effects derived from industrial automation ought to be investigated with a larger sample size. Relevance to industry: The reduction of rest opportunities observed on a semi-automated production line requires the attention of ergonomists when planning or redesigning tasks in such production lines. Lack of rest is considered a risk factor for the development of musculoskeletal disorders.
47.	Nüske, Ralf, et al. (författare) Time-resolved x-ray scattering from laser-molten indium antimonide. 2010 Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 1089-7623 .- 0034-6748. ; 81:1 Tidskriftsartikel (refereegranskat)abstract We demonstrate a concept to study transient liquids with picosecond time-resolved x-ray scattering in a high-repetition-rate configuration. Femtosecond laser excitation of crystalline indium antimonide (InSb) induces ultrafast melting, which leads to a loss of the long-range order. The remaining local correlations of the liquid result in broad x-ray diffraction rings, which are measured as a function of delay time. After 2 ns the liquid structure factor shows close agreement with that of equilibrated liquid InSb. The measured decay of the liquid scattering intensity corresponds to the resolidification rate of 1 m/s in InSb.
48.	Nüske, Ralf, et al. (författare) Transforming graphite to nanoscale diamonds by a femtosecond laser pulse 2012 Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 100:4 Tidskriftsartikel (refereegranskat)abstract Formation of cubic diamond from graphite following irradiation by a single, intense, ultra-short laser pulse has been observed. Highly oriented pyrolytic graphite (HOPG) samples were irradiated by a 100 fs pulse with a center wavelength of 800 nm. Following laser exposure, the HOPG samples were studied using Raman spectroscopy of the sample surface. In the laser-irradiated areas, nanoscale cubic diamond crystals have been formed. The exposed areas were also studied using grazing incidence x-ray powder diffraction showing a restacking of planes from hexagonal graphite to rhombohedral graphite. (C) 2012 American Institute of Physics. [doi:10.1063/1.3678190]
49.	Persson, Anna, et al. (författare) Real-time observation of coherent acoustic phonons generated by an acoustically mismatched optoacoustic transducer using x-ray diffraction 2015 Ingår i: Applied Physics Reviews. - New York : AIP Publishing. - 1931-9401. ; 118:18 Tidskriftsartikel (refereegranskat)abstract The spectrum of laser-generated acoustic phonons in indium antimonide coated with a thin nickel film has been studied using time-resolved x-ray diffraction. Strain pulses that can be considered to be built up from coherent phonons were generated in the nickel film by absorption of short laser pulses. Acoustic reflections at the Ni-InSb interface leads to interference that strongly modifies the resulting phonon spectrum. The study was performed with high momentum transfer resolution together with high time resolution. This was achieved by using a third-generation synchrotron radiation source that provided a high-brightness beam and an ultrafast x-ray streak camera to obtain a temporal resolution of 10 ps. We also carried out simulations, using commercial finite element software packages and on-line dynamic diffraction tools. Using these tools, it is possible to calculate the time-resolved x-ray reflectivity from these complicated strain shapes. The acoustic pulses have a peak strain amplitude close to 1%, and we investigated the possibility to use this device as an x-ray switch. At a bright source optimized for hard x-ray generation, the low reflectivity may be an acceptable trade-off to obtain a pulse duration that is more than an order of magnitude shorter. (C) 2015 Author(s).
50.	Schiefer, Christoph, et al. (författare) PEPPA - Exchange Platform for Measurements of Occupational Physical Activity and Physical Workload 2021 Ingår i: Proceedings of the 21st Congress of the International Ergonomics Association (IEA 2021). Volume V: Methods & Approaches. - Cham, Schweiz : Springer. - 9783030746131 ; , s. 175-182 Konferensbidrag (refereegranskat)abstract Technical measurements allow an objective assessment of MSD riskfactors at work. There is a need for common standards regarding data collection and processing, as well as an exchange platform storing measurement data of occupational physical activity and workload for further analysis. Several research institutes started a feasibility study towork on developing standards for assessment of risk factors and implement them in an exchange platform prototype. The first prototype already demonstrates a technical feasibility. Coordination and structure of the contents, as well as estimates of costs and efforts needed for further development need more examination in order to arrive at a final platform with good feasibility.

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