| 1. |
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| 2. |
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| 3. |
- Tierney, W., et al.
(författare)
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A creative destruction approach to replication : Implicit work and sex morality across cultures
- 2021
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Ingår i: Journal of Experimental Social Psychology. - : Elsevier BV. - 0022-1031 .- 1096-0465. ; 93
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Tidskriftsartikel (refereegranskat)abstract
- How can we maximize what is learned from a replication study? In the creative destruction approach to replication, the original hypothesis is compared not only to the null hypothesis, but also to predictions derived from multiple alternative theoretical accounts of the phenomenon. To this end, new populations and measures are included in the design in addition to the original ones, to help determine which theory best accounts for the results across multiple key outcomes and contexts. The present pre-registered empirical project compared the Implicit Puritanism account of intuitive work and sex morality to theories positing regional, religious, and social class differences; explicit rather than implicit cultural differences in values; self-expression vs. survival values as a key cultural fault line; the general moralization of work; and false positive effects. Contradicting Implicit Puritanism's core theoretical claim of a distinct American work morality, a number of targeted findings replicated across multiple comparison cultures, whereas several failed to replicate in all samples and were identified as likely false positives. No support emerged for theories predicting regional variability and specific individual-differences moderators (religious affiliation, religiosity, and education level). Overall, the results provide evidence that work is intuitively moralized across cultures.
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| 4. |
- Ferreira, Mjv, et al.
(författare)
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Poster Session 3 : Tuesday 5 May 2015, 08
- 2015
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Ingår i: European Heart Journal Cardiovascular Imaging. - : Oxford University Press (OUP). - 2047-2404 .- 2047-2412. ; 16 Suppl 1
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Tidskriftsartikel (refereegranskat)
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| 5. |
- Santangelo, James S., et al.
(författare)
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Global urban environmental change drives adaptation in white clover
- 2022
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 375
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Tidskriftsartikel (refereegranskat)abstract
- Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural dines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale.
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| 6. |
- Bouwmeester, S, et al.
(författare)
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Registered Replication Report: Rand, Greene, and Nowak (2012) : Multilab direct replication of: Study 7 from Rand, D. G., Greene, J. D., & Nowak, M. A. (2012) Spontaneous giving and calculated greed. Nature, 489, 427–430.
- 2017
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Ingår i: Perspectives on Psychological Science. - : Sage Publications. - 1745-6916 .- 1745-6924. ; 12:3, s. 527-542
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Tidskriftsartikel (refereegranskat)abstract
- In an anonymous 4-person economic game, participants contributed more money to a common project (i.e., cooperated) when required to decide quickly than when forced to delay their decision (Rand, Greene & Nowak, 2012), a pattern consistent with the social heuristics hypothesis proposed by Rand and colleagues. The results of studies using time pressure have been mixed, with some replication attempts observing similar patterns (e.g., Rand et al., 2014) and others observing null effects (e.g., Tinghög et al., 2013; Verkoeijen & Bouwmeester, 2014). This Registered Replication Report (RRR) assessed the size and variability of the effect of time pressure on cooperative decisions by combining 21 separate, preregistered replications of the critical conditions from Study 7 of the original article (Rand et al., 2012). The primary planned analysis used data from all participants who were randomly assigned to conditions and who met the protocol inclusion criteria (an intent-to-treat approach that included the 65.9% of participants in the time-pressure condition and 7.5% in the forced-delay condition who did not adhere to the time constraints), and we observed a difference in contributions of −0.37 percentage points compared with an 8.6 percentage point difference calculated from the original data. Analyzing the data as the original article did, including data only for participants who complied with the time constraints, the RRR observed a 10.37 percentage point difference in contributions compared with a 15.31 percentage point difference in the original study. In combination, the results of the intent-to-treat analysis and the compliant-only analysis are consistent with the presence of selection biases and the absence of a causal effect of time pressure on cooperation.
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| 7. |
- Bouwmeester, Sjoerd, et al.
(författare)
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Registered Replication Report : Rand, Greene, and Nowak (2012)
- 2017
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Ingår i: Perspectives on Psychological Science. - : SAGE Publications. - 1745-6916 .- 1745-6924. ; 12:3, s. 527-542
-
Tidskriftsartikel (refereegranskat)abstract
- In an anonymous 4-person economic game, participants contributed more money to a common project (i.e., cooperated) when required to decide quickly than when forced to delay their decision (Rand, Greene & Nowak, 2012), a pattern consistent with the social heuristics hypothesis proposed by Rand and colleagues. The results of studies using time pressure have been mixed, with some replication attempts observing similar patterns (e.g., Rand et al., 2014) and others observing null effects (e.g., Tinghög et al., 2013; Verkoeijen & Bouwmeester, 2014). This Registered Replication Report (RRR) assessed the size and variability of the effect of time pressure on cooperative decisions by combining 21 separate, preregistered replications of the critical conditions from Study 7 of the original article (Rand et al., 2012). The primary planned analysis used data from all participants who were randomly assigned to conditions and who met the protocol inclusion criteria (an intent-to-treat approach that included the 65.9% of participants in the time-pressure condition and 7.5% in the forced-delay condition who did not adhere to the time constraints), and we observed a difference in contributions of −0.37 percentage points compared with an 8.6 percentage point difference calculated from the original data. Analyzing the data as the original article did, including data only for participants who complied with the time constraints, the RRR observed a 10.37 percentage point difference in contributions compared with a 15.31 percentage point difference in the original study. In combination, the results of the intent-to-treat analysis and the compliant-only analysis are consistent with the presence of selection biases and the absence of a causal effect of time pressure on cooperation.
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| 8. |
- Körber, R., et al.
(författare)
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SQUIDs in biomagnetism: A roadmap towards improved healthcare
- 2016
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Ingår i: Superconductors Science and Technology. - : IOP Publishing. - 0953-2048 .- 1361-6668. ; 29:11
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Tidskriftsartikel (refereegranskat)abstract
- Globally, the demand for improved health care delivery while managing escalating costs is a major challenge. Measuring the biomagnetic fields that emanate from the human brain already impacts the treatment of epilepsy, brain tumours and other brain disorders. This roadmap explores how superconducting technologies are poised to impact health care. Biomagnetism is the study of magnetic fields of biological origin. Biomagnetic fields are typically very weak, often in the femtotesla range, making their measurement challenging. The earliest in vivo human measurements were made with room-temperature coils. In 1963, Baule and McFee (1963 Am. Heart J. 55 95-6) reported the magnetic field produced by electric currents in the heart ('magnetocardiography'), and in 1968, Cohen (1968 Science 161 784-6) described the magnetic field generated by alpha-rhythm currents in the brain ('magnetoencephalography'). Subsequently, in 1970, Cohen et al (1970 Appl. Phys. Lett. 16 278-80) reported the recording of a magnetocardiogram using a Superconducting QUantum Interference Device (SQUID). Just two years later, in 1972, Cohen (1972 Science 175 664-6) described the use of a SQUID in magnetoencephalography. These last two papers set the scene for applications of SQUIDs in biomagnetism, the subject of this roadmap. The SQUID is a combination of two fundamental properties of superconductors. The first is flux quantization - the fact that the magnetic flux Φ in a closed superconducting loop is quantized in units of the magnetic flux quantum, Φ0 ≡ h/2e, ≈ 2.07 × 10-15 Tm2 (Deaver and Fairbank 1961 Phys. Rev. Lett. 7 43-6, Doll R and Nabauer M 1961 Phys. Rev. Lett. 7 51-2). Here, h is the Planck constant and e the elementary charge. The second property is the Josephson effect, predicted in 1962 by Josephson (1962 Phys. Lett. 1 251-3) and observed by Anderson and Rowell (1963 Phys. Rev. Lett. 10 230-2) in 1963. The Josephson junction consists of two weakly coupled superconductors separated by a tunnel barrier or other weak link. A tiny electric current is able to flow between the superconductors as a supercurrent, without developing a voltage across them. At currents above the 'critical current' (maximum supercurrent), however, a voltage is developed. In 1964, Jaklevic et al (1964 Phys. Rev. Lett. 12 159-60) observed quantum interference between two Josephson junctions connected in series on a superconducting loop, giving birth to the dc SQUID. The essential property of the SQUID is that a steady increase in the magnetic flux threading the loop causes the critical current to oscillate with a period of one flux quantum. In today's SQUIDs, using conventional semiconductor readout electronics, one can typically detect a change in Φ corresponding to 10-6 Φ0 in one second. Although early practical SQUIDs were usually made from bulk superconductors, for example, niobium or Pb-Sn solder blobs, today's devices are invariably made from thin superconducting films patterned with photolithography or even electron lithography. An extensive description of SQUIDs and their applications can be found in the SQUID Handbooks (Clarke and Braginski 2004 Fundamentals and Technology of SQUIDs and SQUID Systems vol I (Weinheim, Germany: Wiley-VCH), Clarke and Braginski 2006 Applications of SQUIDs and SQUID Systems vol II (Weinheim, Germany: Wiley-VCH)). The roadmap begins (chapter 1) with a brief review of the state-of-the-art of SQUID-based magnetometers and gradiometers for biomagnetic measurements. The magnetic field noise referred to the pick-up loop is typically a few fT Hz-1/2, often limited by noise in the metallized thermal insulation of the dewar rather than by intrinsic SQUID noise. The authors describe a pathway to achieve an intrinsic magnetic field noise as low as 0.1 fT Hz-1/2, approximately the Nyquist noise of the human body. They also descibe a technology to defeat dewar noise. Chapter 2 reviews the neuroscientific and clinical use of magnetoencephalography (MEG), by far the most widespread application of biomagnetism with systems containing ty ically 300 sensors cooled to liquid-helium temperature, 4.2 K. Two important clinical applications are presurgical mapping of focal epilepsy and of eloquent cortex in brain-tumor patients. Reducing the sensor-to-brain separation and the system noise level would both improve spatial resolution. The very recent commercial innovation that replaces the need for frequent manual transfer of liquid helium with an automated system that collects and liquefies the gas and transfers the liquid to the dewar will make MEG systems more accessible. A highly promising means of placing the sensors substantially closer to the scalp for MEG is to use high-transition-temperature (high-T c) SQUID sensors and flux transformers (chapter 3). Operation of these devices at liquid-nitrogen temperature, 77 K, enables one to minimize or even omit metallic thermal insulation between the sensors and the dewar. Noise levels of a few fT Hz-1/2 have already been achieved, and lower values are likely. The dewars can be made relatively flexible, and thus able to be placed close to the skull irrespective of the size of the head, potentially providing higher spatial resolution than liquid-helium based systems. The successful realization of a commercial high-T c MEG system would have a major commercial impact. Chapter 4 introduces the concept of SQUID-based ultra-low-field magnetic resonance imaging (ULF MRI) operating at typically several kHz, some four orders of magnitude lower than conventional, clinical MRI machines. Potential advantages of ULF MRI include higher image contrast than for conventional MRI, enabling methodologies not currently available. Examples include screening for cancer without a contrast agent, imaging traumatic brain injury (TBI) and degenerative diseases such as Alzheimer's, and determining the elapsed time since a stroke. The major current problem with ULF MRI is that its signal-to-noise ratio (SNR) is low compared with high-field MRI. Realistic solutions to this problem are proposed, including implementing sensors with a noise level of 0.1 fT Hz-1/2. A logical and exciting prospect (chapter 5) is to combine MEG and ULF MRI into a single system in which both signal sources are detected with the same array of SQUIDs. A prototype system is described. The combination of MEG and ULF MRI allows one to obtain structural images of the head concurrently with the recording of brain activity. Since all MEG images require an MRI to determine source locations underlying the MEG signal, the combined modality would give a precise registration of the two images; the combination of MEG with high-field MRI can produce registration errors as large as 5 mm. The use of multiple sensors for ULF MRI increases both the SNR and the field of view. Chapter 6 describes another potentially far-reaching application of ULF MRI, namely neuronal current imaging (NCI) of the brain. Currently available neuronal imaging techniques include MEG, which is fast but has relatively poor spatial resolution, perhaps 10 mm, and functional MRI (fMRI) which has a millimeter resolution but is slow, on the order of seconds, and furthermore does not directly measure neuronal signals. NCI combines the ability of direct measurement of MEG with the spatial precision of MRI. In essence, the magnetic fields generated by neural currents shift the frequency of the magnetic resonance signal at a location that is imaged by the three-dimensional magnetic field gradients that form the basis of MRI. The currently achieved sensitivity of NCI is not quite sufficient to realize its goal, but it is close. The realization of NCI would represent a revolution in functional brain imaging. Improved techniques for immunoassay are always being sought, and chapter 7 introduces an entirely new topic, magnetic nanoparticles for immunoassay. These particles are bio-funtionalized, for example with a specific antibody which binds to its corresponding antigen, if it is present. Any resulting changes in the properties of the nanoparticles are detected with a SQUID. For liquid-phase detection, there are three ba ic methods: AC susceptibility, magnetic relaxation and remanence measurement. These methods, which have been successfully implemented for both in vivo and ex vivo applications, are highly sensitive and, although further development is required, it appears highly likely that at least some of them will be commercialized. © 2016 IOP Publishing Ltd.
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| 9. |
- Chapple, Iain L C, et al.
(författare)
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Interaction of lifestyle, behaviour or systemic diseases with dental caries and periodontal diseases: consensus report of group 2 of the joint EFP/ORCA workshop on the boundaries between caries and periodontal diseases.
- 2017
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Ingår i: Journal of clinical periodontology. - : Wiley. - 1600-051X .- 0303-6979. ; 44:Suppl 18
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Tidskriftsartikel (refereegranskat)abstract
- Periodontal diseases and dental caries are the most common diseases of humans and the main cause of tooth loss. Both diseases can lead to nutritional compromise and negative impacts upon self-esteem and quality of life. As complex chronic diseases, they share common risk factors, such as a requirement for a pathogenic plaque biofilm, yet they exhibit distinct pathophysiologies. Multiple exposures contribute to their causal pathways, and susceptibility involves risk factors that are inherited (e.g. genetic variants), and those that are acquired (e.g. socio-economic factors, biofilm load or composition, smoking, carbohydrate intake). Identification of these factors is crucial in the prevention of both diseases as well as in their management.To systematically appraise the scientific literature to identify potential risk factors for caries and periodontal diseases.One systematic review (genetic risk factors), one narrative review (role of diet and nutrition) and reference documentation for modifiable acquired risk factors common to both disease groups, formed the basis of the report.There is moderately strong evidence for a genetic contribution to periodontal diseases and caries susceptibility, with an attributable risk estimated to be up to 50%. The genetics literature for periodontal disease is more substantial than for caries and genes associated with chronic periodontitis are the vitamin D receptor (VDR), Fc gamma receptor IIA (Fc-γRIIA) and Interleukin 10 (IL10) genes. For caries, genes involved in enamel formation (AMELX, AMBN, ENAM, TUFT, MMP20, and KLK4), salivary characteristics (AQP5), immune regulation and dietary preferences had the largest impact. No common genetic variants were found. Fermentable carbohydrates (sugars and starches) were the most relevant common dietary risk factor for both diseases, but associated mechanisms differed. In caries, the fermentation process leads to acid production and the generation of biofilm components such as Glucans. In periodontitis, glycaemia drives oxidative stress and advanced glycation end-products may also trigger a hyper inflammatory state. Micronutrient deficiencies, such as for vitamin C, vitamin D or vitamin B12, may be related to the onset and progression of both diseases. Functional foods or probiotics could be helpful in caries prevention and periodontal disease management, although evidence is limited and biological mechanisms not fully elucidated. Hyposalivation, rheumatoid arthritis, smoking/tobacco use, undiagnosed or sub-optimally controlled diabetes and obesity are common acquired risk factors for both caries and periodontal diseases.
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| 10. |
- Dideriksen, Jakob L., et al.
(författare)
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Electrical stimulation of afferent pathways for the suppression of pathological tremor
- 2017
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Ingår i: Frontiers in Neuroscience. - : Frontiers Media SA. - 1662-4548 .- 1662-453X. ; 11, s. 1-11
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Tidskriftsartikel (refereegranskat)abstract
- Pathological tremors are involuntary oscillatory movements which cannot be fully attenuated using conventional treatments. For this reason, several studies have investigated the use of neuromuscular electrical stimulation for tremor suppression. In a recent study, however, we found that electrical stimulation below the motor threshold also suppressed tremor, indicating involvement of afferent pathways. In this study, we further explored this possibility by systematically investigating how tremor suppression by afferent stimulation depends on the stimulation settings. In this way, we aimed at identifying the optimal stimulation strategy, as well as to elucidate the underlying physiological mechanisms of tremor suppression. Stimulation strategies varying the stimulation intensity and pulse timing were tested in nine tremor patients using either intramuscular or surface stimulation. Significant tremor suppression was observed in six patients (tremor suppression > 75% was observed in three patients) and the average optimal suppression level observed across all subjects was 52%. The efficiency for each stimulation setting, however, varied substantially across patients and it was not possible to identify a single set of stimulation parameters that yielded positive results in all patients. For example, tremor suppression was achieved both with stimulation delivered in an out-of-phase pattern with respect to the tremor, and with random timing of the stimulation. Overall, these results indicate that low-current stimulation of afferent fibers is a promising approach for tremor suppression, but that further research is required to identify how the effect can be maximized in the individual patient.
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| 11. |
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| 12. |
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| 13. |
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| 14. |
- Laine, Christine M., et al.
(författare)
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WNT1 Mutations in Early-Onset Osteoporosis and Osteogenesis Imperfecta
- 2013
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Ingår i: New England Journal of Medicine. - 0028-4793 .- 1533-4406. ; 368:19, s. 1809-1816
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Tidskriftsartikel (refereegranskat)abstract
- This report identifies human skeletal diseases associated with mutations in WNT1. In 10 family members with dominantly inherited, early-onset osteoporosis, we identified a heterozygous missense mutation in WNT1, c.652T -> G (p.Cys218Gly). In a separate family with 2 siblings affected by recessive osteogenesis imperfecta, we identified a homozygous nonsense mutation, c.884C -> A, p.Ser295(star). In vitro, aberrant forms of the WNT1 protein showed impaired capacity to induce canonical WNT signaling, their target genes, and mineralization. In mice, Wnt1 was clearly expressed in bone marrow, especially in B-cell lineage and hematopoietic progenitors; lineage tracing identified the expression of the gene in a subset of osteocytes, suggesting the presence of altered cross-talk in WNT signaling between the hematopoietic and osteoblastic lineage cells in these diseases.
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| 15. |
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| 16. |
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| 17. |
- McCarthy, Randy J., et al.
(författare)
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Registered Replication Report on Srull and Wyer (1979)
- 2018
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Ingår i: Advances in Methods and Practices in Psychological Science. - : SAGE Publications Inc. - 2515-2459 .- 2515-2467. ; 1:3, s. 321-336
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Tidskriftsartikel (refereegranskat)abstract
- Srull and Wyer (1979) demonstrated that exposing participants to more hostility-related stimuli caused them subsequently to interpret ambiguous behaviors as more hostile. In their Experiment 1, participants descrambled sets of words to form sentences. In one condition, 80% of the descrambled sentences described hostile behaviors, and in another condition, 20% described hostile behaviors. Following the descrambling task, all participants read a vignette about a man named Donald who behaved in an ambiguously hostile manner and then rated him on a set of personality traits. Next, participants rated the hostility of various ambiguously hostile behaviors (all ratings on scales from 0 to 10). Participants who descrambled mostly hostile sentences rated Donald and the ambiguous behaviors as approximately 3 scale points more hostile than did those who descrambled mostly neutral sentences. This Registered Replication Report describes the results of 26 independent replications (N = 7,373 in the total sample; k = 22 labs and N = 5,610 in the primary analyses) of Srull and Wyer?s Experiment 1, each of which followed a preregistered and vetted protocol. A random-effects meta-analysis showed that the protagonist was seen as 0.08 scale points more hostile when participants were primed with 80% hostile sentences than when they were primed with 20% hostile sentences (95% confidence interval, CI = [0.004, 0.16]). The ambiguously hostile behaviors were seen as 0.08 points less hostile when participants were primed with 80% hostile sentences than when they were primed with 20% hostile sentences (95% CI = [?0.18, 0.01]). Although the confidence interval for one outcome excluded zero and the observed effect was in the predicted direction, these results suggest that the currently used methods do not produce an assimilative priming effect that is practically and routinely detectable.
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| 18. |
- Mora, A., et al.
(författare)
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Gaia : Focus, straylight and basic angle
- 2016
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Ingår i: Space Telescopes and Instrumentation 2016: Optical, Infrared, and Millimeter Wave. - : SPIE. - 9781510601871 ; 9904
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Konferensbidrag (refereegranskat)abstract
- The Gaia all-sky astrometric survey is challenged by several issues affecting the spacecraft stability. Amongst them, we find the focus evolution, straylight and basic angle variations Contrary to pre-launch expectations, the image quality is continuously evolving, during commissioning and the nominal mission. Payload decontaminations and wavefront sensor assisted refocuses have been carried out to recover optimum performance. An ESA-Airbus DS working group analysed the straylight and basic angle issues and worked on a detailed root cause analysis. In parallel, the Gaia scientists have also analysed the data, most notably comparing the BAM signal to global astrometric solutions, with remarkable agreement. In this contribution, a status review of these issues will be provided, with emphasis on the mitigation schemes and the lessons learned for future space missions where extreme stability is a key requirement.
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| 19. |
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| 20. |
- Ogishi, M, et al.
(författare)
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Impaired IL-23-dependent induction of IFN-γ underlies mycobacterial disease in patients with inherited TYK2 deficiency
- 2022
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Ingår i: The Journal of experimental medicine. - : Rockefeller University Press. - 1540-9538 .- 0022-1007. ; 219:10
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Tidskriftsartikel (refereegranskat)abstract
- Human cells homozygous for rare loss-of-expression (LOE) TYK2 alleles have impaired, but not abolished, cellular responses to IFN-α/β (underlying viral diseases in the patients) and to IL-12 and IL-23 (underlying mycobacterial diseases). Cells homozygous for the common P1104A TYK2 allele have selectively impaired responses to IL-23 (underlying isolated mycobacterial disease). We report three new forms of TYK2 deficiency in six patients from five families homozygous for rare TYK2 alleles (R864C, G996R, G634E, or G1010D) or compound heterozygous for P1104A and a rare allele (A928V). All these missense alleles encode detectable proteins. The R864C and G1010D alleles are hypomorphic and loss-of-function (LOF), respectively, across signaling pathways. By contrast, hypomorphic G996R, G634E, and A928V mutations selectively impair responses to IL-23, like P1104A. Impairment of the IL-23–dependent induction of IFN-γ is the only mechanism of mycobacterial disease common to patients with complete TYK2 deficiency with or without TYK2 expression, partial TYK2 deficiency across signaling pathways, or rare or common partial TYK2 deficiency specific for IL-23 signaling.
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| 21. |
- Smith, Annabel L., et al.
(författare)
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Global gene flow releases invasive plants from environmental constraints on genetic diversity
- 2020
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 117:8, s. 4218-4227
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Tidskriftsartikel (refereegranskat)abstract
- When plants establish outside their native range, their ability to adapt to the new environment is influenced by both demography and dispersal. However, the relative importance of these two factors is poorly understood. To quantify the influence of demography and dispersal on patterns of genetic diversity underlying adaptation, we used data from a globally distributed demographic research network comprising 35 native and 18 nonnative populations of Plantago lanceolata. Species-specific simulation experiments showed that dispersal would dilute demographic influences on genetic diversity at local scales. Populations in the native European range had strong spatial genetic structure associated with geographic distance and precipitation seasonality. In contrast, nonnative populations had weaker spatial genetic structure that was not associated with environmental gradients but with higher within-population genetic diversity. Our findings show that dispersal caused by repeated, long-distance, human-mediated introductions has allowed invasive plant populations to overcome environmental constraints on genetic diversity, even without strong demographic changes. The impact of invasive plants may, therefore, increase with repeated introductions, highlighting the need to constrain future introductions of species even if they already exist in an area.
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| 22. |
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| 23. |
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| 24. |
- Verschuere, Bruno, et al.
(författare)
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Registered Replication Report on Mazar, Amir, and Ariely (2008)
- 2018
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Ingår i: Advances in Methods and Practices in Psychological Science. - : SAGE Publications. - 2515-2459 .- 2515-2467. ; 1:3, s. 299-317
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Tidskriftsartikel (refereegranskat)abstract
- The self-concept maintenance theory holds that many people will cheat in order to maximize self-profit, but only to the extent that they can do so while maintaining a positive self-concept. Mazar, Amir, and Ariely (2008, Experiment 1) gave participants an opportunity and incentive to cheat on a problem-solving task. Prior to that task, participants either recalled the Ten Commandments (a moral reminder) or recalled 10 books they had read in high school (a neutral task). Results were consistent with the self-concept maintenance theory. When given the opportunity to cheat, participants given the moral-reminder priming task reported solving 1.45 fewer matrices than did those given a neutral prime (Cohen’s d = 0.48); moral reminders reduced cheating. Mazar et al.’s article is among the most cited in deception research, but their Experiment 1 has not been replicated directly. This Registered Replication Report describes the aggregated result of 25 direct replications (total N = 5,786), all of which followed the same preregistered protocol. In the primary meta-analysis (19 replications, total n = 4,674), participants who were given an opportunity to cheat reported solving 0.11 more matrices if they were given a moral reminder than if they were given a neutral reminder (95% confidence interval = [−0.09, 0.31]). This small effect was numerically in the opposite direction of the effect observed in the original study (Cohen’s d = −0.04).
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| 25. |
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| 26. |
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| 27. |
- Arft, M, et al.
(författare)
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Responses of tundra plants to experimental warming : Meta-analysis of the international tundra experiment
- 1999
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Ingår i: Ecological Monographs. - 0012-9615 .- 1557-7015. ; 69:4, s. 491-511
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Tidskriftsartikel (refereegranskat)abstract
- The International Tundra Experiment (ITEX) is a collaborative, multisite experiment using a common temperature manipulation to examine variability in species response across climatic and geographic gradients of tundra ecosystems. ITEX was designed specifically to examine variability in arctic and alpine species response to increased temperature. We compiled from one to four years of experimental data from 13 different ITEX sites and used meta-analysis to analyze responses of plant phenology, growth, and reproduction to experimental warming. Results indicate that key phenological events such as leaf bud burst and flowering occurred earlier in warmed plots throughout the study period; however, there was little impact on growth cessation at the end of the season. Quantitative measures of vegetative growth were greatest in warmed plots in the early years of the experiment, whereas reproductive effort and success increased in later years. A shift away from vegetative growth and toward reproductive effort and success in the fourth treatment year suggests a shift from the initial response to a secondary response. The change in vegetative response may be due to depletion of stored plant reserves, whereas the lag in reproductive response may be due to the formation of flower buds one to several seasons prior to flowering. Both vegetative and reproductive responses varied among life-forms; herbaceous forms had stronger and more consistent vegetative growth responses than did woody forms. The greater responsiveness of the herbaceous forms may be attributed to their more flexible morphology and to their relatively greater proportion of stored plant reserves. Finally, warmer, low arctic sites produced the strongest growth responses, but colder sites produced a greater reproductive response. Greater resource investment in vegetative growth may be a conservative strategy in the Low Arctic, where there is more competition for light, nutrients, or water, and there may be little opportunity for successful germination or seedling development. In contrast, in the High Arctic, heavy investment in producing seed under a higher temperature scenario may provide an opportunity for species to colonize patches of unvegetated ground. The observed differential response to warming suggests that the primary forces driving the response vary across climatic zones, functional groups, and through time.
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| 28. |
- Bengtsson, Fia, 1986-, et al.
(författare)
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Environmental drivers of Sphagnum growth in peatlands across the Holarctic region
- 2021
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Ingår i: Journal of Ecology. - : John Wiley & Sons. - 0022-0477 .- 1365-2745. ; 109:1, s. 417-431
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Tidskriftsartikel (refereegranskat)abstract
- The relative importance of global versus local environmental factors for growth and thus carbon uptake of the bryophyte genusSphagnum-the main peat-former and ecosystem engineer in northern peatlands-remains unclear. We measured length growth and net primary production (NPP) of two abundantSphagnumspecies across 99 Holarctic peatlands. We tested the importance of previously proposed abiotic and biotic drivers for peatland carbon uptake (climate, N deposition, water table depth and vascular plant cover) on these two responses. Employing structural equation models (SEMs), we explored both indirect and direct effects of drivers onSphagnumgrowth. Variation in growth was large, but similar within and between peatlands. Length growth showed a stronger response to predictors than NPP. Moreover, the smaller and denserSphagnum fuscumgrowing on hummocks had weaker responses to climatic variation than the larger and looserSphagnum magellanicumgrowing in the wetter conditions. Growth decreased with increasing vascular plant cover within a site. Between sites, precipitation and temperature increased growth forS. magellanicum. The SEMs indicate that indirect effects are important. For example, vascular plant cover increased with a deeper water table, increased nitrogen deposition, precipitation and temperature. These factors also influencedSphagnumgrowth indirectly by affecting moss shoot density. Synthesis. Our results imply that in a warmer climate,S. magellanicumwill increase length growth as long as precipitation is not reduced, whileS. fuscumis more resistant to decreased precipitation, but also less able to take advantage of increased precipitation and temperature. Such species-specific sensitivity to climate may affect competitive outcomes in a changing environment, and potentially the future carbon sink function of peatlands.
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| 29. |
- Böttiger, Ylva, et al.
(författare)
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Development and pilot testing of PHARAO-a decision support system for pharmacological risk assessment in the elderly
- 2018
-
Ingår i: European Journal of Clinical Pharmacology. - : SPRINGER HEIDELBERG. - 0031-6970 .- 1432-1041. ; 74:3, s. 365-371
-
Tidskriftsartikel (refereegranskat)abstract
- The aims of this study are to describe the development of PHARAO (Pharmacological Risk Assessment Online), a decision support system providing a risk profile for adverse events, associated with combined effects of multiple medicines, and to present data from a pilot study, testing the use, functionality, and acceptance of the PHARAO system in a clinical setting. About 1400 substances were scored in relation to their risk to cause any of nine common and/or serious adverse effects. Algorithms for each adverse effect score were developed to create individual risk profiles from the patients list of medication. The system was tested and integrated to the electronic medical record, during a 4-month period in two geriatric wards and three primary healthcare centers, and a questionnaire was answered by the users before and after the test period. A total of 732 substances were tagged with one or more of the nine risks, most commonly with the risk of sedation or seizures. During the pilot, the system was used 933 times in 871 patients. The most common signals generated by PHARAO in these patients were related to the risks of constipation, sedation, and bleeding. A majority of responders considered PHARAO easy to use and that it gives useful support in performing medication reviews. The PHARAO decision support system, designed as a complement to a database on drug-drug interactions used nationally, worked as intended and was appreciated by the users during a 4-month test period. Integration aspects need to be improved to minimize unnecessary signaling.
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| 30. |
- Calás, M. B., et al.
(författare)
-
What to do about "The Human" in Organization Studies? : Thinking/saying/ doing with the Anthropocene, pandemics, and thereafters
- 2023
-
Ingår i: A Research Agenda for Organization Studies, Feminisms and New Materialisms. - : Edward Elgar Publishing Ltd.. - 9781800881273 - 9781800881266 ; , s. 177-194
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Each of the chapters in this volume, from the introduction to this end(ing), engaged in a conversation about producing knowledge in, about, with "organization studies" at a time when we (us, the human inhabitants of this Earth) are facing calamitous conditions, probably leading to our/its destruction, and (some more than others) are wondering what is to be done. As members of the management and organization studies (MOS) scholarly community, all the authors in this project are deeply concerned about the "knowledge" our common field is producing as "legitimate", for it seems not only inadequate for addressing those calamitous conditions but also that this kind of knowledge may be implicated in reproducing the harms we all decry. The aim here has not been to critique the field on the basis of what it produces but to acknowledge conditions perpetuating the production of those forms of knowledge more generally, and to offer positive alternatives which may make a difference in what is produced, perhaps contributing to a better world‚ over and over again. The message this chapter and all other chapters hope to convey is the possibility of "thinking, saying and doing otherwise". But can we truly question the very notion of "the human" supporting "legitimate knowledge"? Can we truly focus on producing processual knowledge with indefinite aims? In other words, is the becoming of an organization studies produced with feminist new materialisms possible? Responding to those questions, and following the original proposal for this volume, this chapter is the voice of the collectivity articulating 'the-world-and-beyond' as envisioned in each of the prior chapters. Taking this approach resonates as well with new materialisms: "'a doing with' which cannot be a 'doing alone' -more like a world of on-going assembling".
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| 31. |
- Dideriksen, Jakob L., et al.
(författare)
-
Physiological recruitment of motor units by high-frequency electrical stimulation of afferent pathways
- 2015
-
Ingår i: Journal of Applied Physiology. - : American Physiological Society. - 8750-7587 .- 1522-1601. ; 118:3, s. 365-376
-
Tidskriftsartikel (refereegranskat)abstract
- Neuromuscular electrical stimulation (NMES) is commonly used in rehabilitation, but electrically evoked muscle activation is in several ways different from voluntary muscle contractions. These differences lead to challenges in the use of NMES for restoring muscle function. We investigated the use of low-current, high-frequency nerve stimulation to activate the muscle via the spinal motoneuron (MN) pool to achieve more natural activation patterns. Using a novel stimulation protocol, the H-reflex responses to individual stimuli in a train of stimulation pulses at 100 Hz were reliably estimated with surface EMG during low-level contractions. Furthermore, single motor unit recruitment by afferent stimulation was analyzed with intramuscular EMG. The results showed that substantially elevated H-reflex responses were obtained during 100-Hz stimulation with respect to a lower stimulation frequency. Furthermore, motor unit recruitment using 100-Hz stimulation was not fully synchronized, as it occurs in classic NMES, and the discharge rates differed among motor units because each unit was activated only after a specific number of stimuli. The most likely mechanism behind these observations is the temporal summation of subthreshold excitatory postsynaptic potentials from Ia fibers to the MNs. These findings and their interpretation were also verified by a realistic simulation model of afferent stimulation of a MN population. These results suggest that the proposed stimulation strategy may allow generation of considerable levels of muscle activation by
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| 32. |
- Ekblad, Laura L., et al.
(författare)
-
Midlife insulin resistance, APOE genotype, and late-life brain amyloid accumulation
- 2018
-
Ingår i: Neurology. - : Lippincott Williams & Wilkins. - 0028-3878 .- 1526-632X. ; 90:13, s. e1150-e1157
-
Tidskriftsartikel (refereegranskat)abstract
- Objective To examine whether midlife insulin resistance is an independent risk factor for brain amyloid accumulation in vivo after 15 years, and whether this risk is modulated by APOE epsilon 4 genotype. Methods This observational study examined 60 elderly volunteers without dementia (mean age at baseline 55.4 and at follow-up 70.9 years, 55.5% women) from the Finnish population-based, nationwide Health2000 study with [C-11]Pittsburgh compound B-PET imaging in 2014-2016. The participants were recruited according to their homeostatic model assessment of insulin resistance (HOMA-IR) values in the year 2000, and their APOE epsilon 4 genotype. The exposure group (IR+, n = 30) consisted of individuals with HOMA-IR > 2.17 at baseline (highest tertile of the Health2000 study population), and the control group (IR-, n = 30) consisted of individuals with HOMA-IR < 1.25 at baseline (lowest tertile). The groups were enriched for APOE epsilon 4 carriers, resulting in 50% (n = 15) APOE epsilon 4 carriers in both groups. Analyses were performed with multivariate logistic and linear regression. Results An amyloid-positive PET scan was found in 33.3% of the IR-group and 60.0% of the IR+ group (odds ratio 3.0, 95% confidence interval 1.1-8.9, p = 0.04). The increased risk was seen in carriers and noncarriers of APOE epsilon 4 genotype. Higher midlife, but not late-life continuous HOMA-IR was associated with a greater brain amyloid burden at follow-up after multivariate adjustments for other cognitive and metabolic risk factors (ss = 0.11, 95% confidence interval 0.002-0.22, p = 0.04). Conclusions These results indicate that midlife insulin resistance is an independent risk factor for brain amyloid accumulation in elderly individuals without dementia.
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| 33. |
- Fredriksson, J., et al.
(författare)
-
Wheel force distribution for improved handling in a hybrid electric vehicle using nonlinear control
- 2004
-
Ingår i: Proceedings of the IEEE Conference on Decision and Control. - : IEEE. ; , s. 4081-4086
-
Konferensbidrag (refereegranskat)abstract
- In this paper a vehicle motion controller is presented. The idea is to use generalized forces acting on the center of gravity of the vehicle and then use a control allocation-like method to distribute the generalized forces to wheel forces. The controller is designed based on feedback linearization of a simple vehicle model. The performance of the controller is evaluated by simulations on a more complex vehicle model. The proposed controller can handle the new flexibility introduced by new powertrain configurations, this is shown by using the same controller on two different vehicle configurations.
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| 34. |
- Gallego-Marcos, Ignacio, et al.
(författare)
-
Pool stratification and mixing during a steam injection through spargers: analysis of the PPOOLEX and PANDA experiments
- 2018
-
Ingår i: Nuclear Engineering and Design. - : Elsevier. - 0029-5493 .- 1872-759X. ; 337, s. 300-316
-
Tidskriftsartikel (refereegranskat)abstract
- Spargers are multi-hole injection pipes used in Boiling Water Reactors (BWR) and Advanced Pressurized (AP) reactors to condense steam in large water pools. A steam injection induces heat, momentum and mass sources that depend on the steam injection conditions and can result in thermal stratification or mixing of the pool. Thermal stratification reduces the steam condensation capacity of the pool, increases the pool surface temperature and thus the containment pressure. Development of models with predictive capabilities requires the understanding of basic phenomena that govern the behavior of the complex multi-scale system. The goals of this work are (i) to analyze and interpret the experiments on steam injection into a pool through spargers performed in the large-scale facilities of PPOOLEX and PANDA, and (ii) to discuss possible modelling approaches for the observed phenomena. A scaling approach was developed to address the most important physical phenomena and regimes relevant to prototypic plant conditions. The focus of the tests was on the low steam mass flux and oscillatory bubble condensation regimes, which are expected during a long-term steam injection transient, e.g. in the case of a Station Black Out (SBO). Exploratory tests were also done for chugging and stable jet conditions. The results showed a similar behavior in PPOOLEX and PANDA in terms of jet induced by steam condensation, pool stratification, and development of hot layer and erosion of the cold one. A correlation using the Richardson number is proposed to model the erosion rate of the cold layer as a function of the pool dimensions and steam injection conditions.
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| 35. |
- Haraldsson, Erik, 1972, et al.
(författare)
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Macroscopic appearance of the major duodenal papilla influences bile duct cannulation: a prospective multicenter study by the Scandinavian Association for Digestive Endoscopy Study Group for ERCP
- 2019
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Ingår i: Gastrointestinal Endoscopy. - : Elsevier BV. - 0016-5107 .- 1097-6779. ; 90:6, s. 957-963
-
Tidskriftsartikel (refereegranskat)abstract
- Background and Aims: Certain appearances of the major duodenal papilla have been claimed to make cannulation more difficult during ERCP. This study uses a validated classification of the endoscopic appearance of the major duodenal papilla to determine if certain types of papilla predispose to difficult cannulation. Methods: Patients with a naïve papilla scheduled for ERCP were included. The papilla was classified into 1 of 4 papilla types before cannulation started. Time to successful bile duct cannulation, attempts, and number of pancreatic duct passages were recorded. Difficult cannulation was defined as after 5 minutes, 5 attempts, or 2 pancreatic guidewire passages. Results: A total of 1401 patients were included from 9 different centers in the Nordic countries. The overall frequency of difficult cannulation was 42% (95% confidence interval [CI], 39%-44%). Type 2 small papilla (52%; 95% CI, 45%-59%) and type 3 protruding or pendulous papilla (48%; 95% CI, 42%-53%) were more frequently difficult to cannulate compared with type 1 regular papilla (36%; 95% CI, 33%-40%; both P <.001). If an inexperienced endoscopist started cannulation, the frequency of failed cannulation increased from 1.9% to 6.3% (P <.0001), even though they were replaced by a senior endoscopist after 5 minutes. Conclusions: The endoscopic appearance of the major duodenal papilla influences bile duct cannulation. Small type 2 and protruding or pendulous type 3 papillae are more frequently difficult to cannulate. In addition, cannulation might even fail more frequently if a beginner starts cannulation. These findings should be taken into consideration when performing studies regarding bile duct cannulation and in training future generations of endoscopists. © 2019 American Society for Gastrointestinal Endoscopy
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| 36. |
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| 37. |
- Hill, M. S., et al.
(författare)
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Reconstruction of Family-Level Phylogenetic Relationships within Demospongiae (Porifera) Using Nuclear Encoded Housekeeping Genes
- 2013
-
Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:1, s. e50437-
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Demosponges are challenging for phylogenetic systematics because of their plastic and relatively simple morphologies and many deep divergences between major clades. To improve understanding of the phylogenetic relationships within Demospongiae, we sequenced and analyzed seven nuclear housekeeping genes involved in a variety of cellular functions from a diverse group of sponges. Methodology/Principal Findings: We generated data from each of the four sponge classes (i.e., Calcarea, Demospongiae, Hexactinellida, and Homoscleromorpha), but focused on family-level relationships within demosponges. With data for 21 newly sampled families, our Maximum Likelihood and Bayesian-based approaches recovered previously phylogenetically defined taxa: Keratosap, Myxospongiaep, Spongillidap, Haploscleromorphap (the marine haplosclerids) and Democlaviap. We found conflicting results concerning the relationships of Keratosap and Myxospongiaep to the remaining demosponges, but our results strongly supported a clade of Haploscleromorphap+Spongillidap+Democlaviap. In contrast to hypotheses based on mitochondrial genome and ribosomal data, nuclear housekeeping gene data suggested that freshwater sponges (Spongillidap) are sister to Haploscleromorphap rather than part of Democlaviap. Within Keratosap, we found equivocal results as to the monophyly of Dictyoceratida. Within Myxospongiaep, Chondrosida and Verongida were monophyletic. A well-supported clade within Democlaviap, Tetractinellidap, composed of all sampled members of Astrophorina and Spirophorina (including the only lithistid in our analysis), was consistently revealed as the sister group to all other members of Democlaviap. Within Tetractinellidap, we did not recover monophyletic Astrophorina or Spirophorina. Our results also reaffirmed the monophyly of order Poecilosclerida (excluding Desmacellidae and Raspailiidae), and polyphyly of Hadromerida and Halichondrida. Conclusions/Significance: These results, using an independent nuclear gene set, confirmed many hypotheses based on ribosomal and/or mitochondrial genes, and they also identified clades with low statistical support or clades that conflicted with traditional morphological classification. Our results will serve as a basis for future exploration of these outstanding questions using more taxon- and gene-rich datasets.
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| 38. |
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| 39. |
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| 40. |
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| 41. |
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| 42. |
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| 43. |
- Jepsen, K., et al.
(författare)
-
Reconstruction of Peri-implant Osseous Defects : A Multicenter Randomized Trial
- 2016
-
Ingår i: Journal of Dental Research. - : Sage Publications. - 0022-0345 .- 1544-0591. ; 95:1, s. 58-66
-
Tidskriftsartikel (refereegranskat)abstract
- There is a paucity of data for the effectiveness of reconstructive procedures in the treatment of peri-implantitis. The objective of this study was to compare reconstruction of peri-implant osseous defects with open flap debridement (OFD) plus porous titanium granules (PTGs) compared with OFD alone. Sixty-three patients (36 female, 27 male; mean age 58.4 y [SD 12.3]), contributing one circumferential peri-implant intraosseous defect, were included in a multinational, multicenter randomized trial using a parallel-group design. After OFD and surface decontamination using titanium brushes and hydrogen peroxide, 33 defects received PTGs. The implants were not submerged. All patients received adjunctive perioperative systemic antibiotics. The primary outcome variable (defect fill) was assessed on digitalized radiographs. Clinical measurements of probing depth (PPD), bleeding on probing (BoP), suppuration, and plaque were taken by blinded examiners. After 12 mo, the test group (OFD plus PTG) showed a mean radiographic defect fill (mesial/distal) of 3.6/3.6 mm compared with 1.1/1.0 in the control group (OFD). Differences were statistically significant in favor of the test group (P < 0.0001). The OFD plus PTG group showed a mean reduction in PPD of 2.8 mm compared with 2.6 mm in the OFD group. BoP was reduced from 89.4% to 33.3% and from 85.8% to 40.4% for the test and control groups, respectively. There was no significant difference in complete resolution of peri-implantitis (PPD <= 4 mm and no BoP at six implant sites and no further bone loss), because this finding was accomplished at 30% of implants in the test group and 23% of implants in the control group. Reconstructive surgery using PTGs resulted in significantly enhanced radiographic defect fill compared with OFD. However, limitations in the lack of ability to discern biomaterial from osseous tissue could not be verified to determine new bone formation. Similar improvements according to clinical measures were obtained after both surgical treatment modalities (ClinicalTrials.gov NCT02406001).
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| 44. |
- Johansson, Morgan, 1971, et al.
(författare)
-
Bebyggelsens motståndsförmåga mot extrem dynamisk belastning, Del 2: Explosion i gatukorsning
- 2012
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Att prediktera den resulterande trycklasten från en explosion som inträffar i en bebyggelse kan varamycket komplicerat. Beroende på explosionskällans placering gentemot sin omgivning samtutformningen av denna kan en mycket stor mängd olika lastsituationer uppstå av vilka en betydandedel utgörs av komplexa kombinationer av interagerande stötvågor.Denna rapport utgör en andra delrapport i projektet Bebyggelsens motståndsförmåga mot extremdynamisk belastning, vars huvudsakliga syfte är att öka kunskapen om bebyggelsens förmåga attabsorbera och motstå de avsevärda påfrestningar den utsätts för vid en explosionsbelastning. Irapporten presenteras en försöksserie i skala 1:5 av en explosion i gatuhörn med syftet att närmarestudera hur stötvågslasten påverkas när den verkar i en geometri motsvarande den i bebyggelsen dären komplex interaktion av sådana fenomen som reflexion, diffraktion samt fördämningseffekter fås.Jämförande beräkningar görs med det generella finita elementprogrammet Autodyn för att närmarestudera hur väl detta klarar av att fånga den resulterande lastbilden i en sådan geometri. Analyser iAutodyn gjordes utfördes försöken och kan därmed användas för att validera programmet. För attjämföra resultaten mellan simulering och beräkning introduceras ett koherensmått för få ett mått påhur väl erhållna tryckkurvor sammanfaller över tiden. Detta koherensmått ger en tydlig indikationpå hur bra hela försöksserien simulerades och med stöd av detta konstateras att analys- ochförsöksresultat visar en mycket god överensstämmelse. Således dras slutsatsen att Autodyn utgör ettmycket kraftfullt verktyg för att förutspå vilken last som kan uppstå vid en explosion i bebyggelse.Som komplement till Autodyn finns det även behov av enklare, mer ingenjörsmässiga,beräkningsverktyg som möjliggör grova och snabba men ändock tillräckligt tillförlitliga överslag avvilken last som fås i en given punkt. En metod för detta presenteras och dess resultat jämförs medbefintliga försöksdata. Överensstämmelsen är fullt acceptabel varför metoden bedöms kunnaanvändas för att ge tillförlitliga grova överslag av resulterande trycklaster från explosionslast.
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| 45. |
- Johansson, Morgan, 1971, et al.
(författare)
-
Bebyggelsens motståndsförmåga mot extrem dynamisk belastning, Del 3: Kapacitet hos byggnader
- 2012
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Räddningsverket, numera Myndigheten för samhällskydd och beredskap (MSB), har ett viktigtansvar för det olycksförebyggande- samt skadebegränsande arbetet i samhället. Det är förRäddningsverket därför också nödvändigt att besitta kompetens och kunnande att hantera extremadynamiska laster samt dess inverkan på bebyggelsen. Därför arbetar Räddningsverket fortlöpandemed att vårda och bygga ut den befintliga kunskapsbas inom detta område och denna rapport är ettled i detta arbete.Denna rapport utgör den tredje och avslutande delen i projektet Bebyggelsens motståndsförmågamot extrem dynamisk belastning. Projektets syfte är att öka kunskapen om extrema dynamiskabelastningar samt om bebyggelsens förmåga att motstå de påfrestningar dessa kan ge upphov till.I denna rapport behandlas bebyggelsens motståndsförmåga, där huvudfokus ägnas åt att beskriva enberäkningsmodell för en dynamiskt belastad balk. En övergripande genomgång ges av vad somskiljer sig i responsen hos en konstruktion som utsätts för en statisk eller dynamisk last. Kritiskaparametrar berörs och det redogörs för vilka egenskaper som är viktiga hos en konstruktion för attklara de påfrestningar som uppkommer vid denna typ av belastning. Vidare ges råd för hur enkonstruktion ska utformas för att uppvisa god motståndsförmåga samt exempel på åtgärder som kangöras för att förstärka en befintlig konstruktion. Samband mellan impulslast, uträttat arbete ochekvivalent statisk last behandlas tillsammans med en genomgång av brottkriterier. Detta illustreras iett utförligt beräkningsexempel där olika delar – lastdefinition, dynamisk respons samt efterföljandekapacitetskontroll hos utsatt konstruktionsdel – behandlas.
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| 46. |
- Johansson, Morgan, 1971, et al.
(författare)
-
Beräkningsanvisningar för strukturell dynamisk respons vid explosionsbelastning
- 2012
-
Ingår i: Bygg & Teknik. - 0281-658X. ; 2012:7, s. 36-41
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Den strukturella responsen hos enexplosionsbelastad konstruktion kanskilja sig väsentligt från den som fåsvid en statisk belastning. Myndighetenför samhällsskydd och beredskap(MSB) har, som en del i sittansvarsområde om det fysiska skyddet,tagit fram en omfattande kunskapsbankinom området dynamiskrespons. För en ökad samhällsnyttaär det önskvärt att vetskapen omdenna når ut till en större krets såatt framtagen kunskap även kan användasvid andra tillämpningar förhantering av extrema dynamiskalaster i bebyggelsen.
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| 47. |
- Johansson, Morgan, 1971, et al.
(författare)
-
Experiments and Analyses of Explosion at an Intersection
- 2008
-
Ingår i: Military Aspects of Blast and Shock. ; 20
-
Konferensbidrag (refereegranskat)abstract
- Predicting the load caused by a propagating blast wave in urban environment is a complextask. For many load cases engineering tools based on empirical data or semi-empiricalmethods, is sufficient. However, when the geometry gets more complex, it might be necessaryto use so-called hydro code programs to calculate the effect of the blast wave. Hence, there isalso a need to verify such programs against experimental results. Once validated, though, suchprograms may be used to better understand the effects of blast load in complex loadsituations.In order to validate the results from the hydro code AUTODYNTM, an experimental testseries, scale 1:5, simulating an explosion in urban environment, was carried out. A simplifiedintersection built up of four concrete boxes, dimension 2.3 m, with a total of eight charges, 0.4and 1.6 kg of PETN, detonated at various locations were registered using 25 pressure gauges.Numerical simulations were carried out in AUTODYN prior to the experimental test series. Inorder to handle the simulations, and thus decrease the calculation time needed, an automaticremapping procedure, in which the progress of the shock front was automatically taken intoconsideration, was developed. To compare experimental and numerical results In addition, acoherence measure was introduced. Out of almost 200 compared pressure-time relations about65 % reached Coh ≥ 0.5; i.e. a limit that indicates very good agreement. Consequently, it isconcluded that AUTODYN manage very well to predict the blast load obtained in a complexurban environment and that it may provide a powerful tool for further blast load studies.An approach for a simplified technique, using superposition of several incident shock waves,to estimate the blast load in a more complex environment is presented and compared to theexperimental and numerical results. This simplified technique is a rather crude instrumentwhen compared to Autodyn. However, it still provides a general idea of which blast wavessums up the resulting pressure time history, and hence may be used in an early stage toapproximately describe the resulting loads on a structure. The results presented herein yield adiscrepancy of the positive and negative impulse intensities of only about 20 % compared tothat in the experiments.
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| 48. |
- Johansson, Morgan, 1971, et al.
(författare)
-
Explosion at an intersection in an Urban Environment – Experiments and analyses
- 2007
-
Ingår i: Shock and Vibration. ; 78
-
Konferensbidrag (refereegranskat)abstract
- This paper describes the experimental and numerical investigation of an explosion in an intersection built up of four concrete boxes. Scaled experiments (1:5) with a total of eight charges (0.4 and 1.6 kg) of PETN detonated at various locations and were registered using a total of 25 pressure gauges. The experimental results were used to validate numerical simulations made in the explicit code AUTODYNTM prior to the experimental performance. An automatic remapping procedure used in the simulations is briefly described and acoherence measure to compare experimental and numerical results is introduced. It isconcluded that AUTODYN managed very well to predict the blast load obtained in acomplex urban environment.
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| 49. |
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| 50. |
- Kontogeorgos, Georgios, et al.
(författare)
-
Hyperparathyroidism in men - morbidity and mortality during 21 years' follow-up
- 2020
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Ingår i: Scandinavian Journal of Clinical & Laboratory Investigation. - : Informa UK Limited. - 0036-5513 .- 1502-7686. ; 80:1, s. 6-13
-
Tidskriftsartikel (refereegranskat)abstract
- Hyperparathyroidism (HPT), including normocalcaemic, vitamin D sufficient (Serum (S)-25(OH)D >= 50 nmol/L) hyperparathyroidism (nHPT), has increasingly been diagnosed in the last few decades due to the more common use of the serum parathyroid hormone (S-PTH) assay. We investigated if men with HPT had higher morbidity and mortality than men without HPT during 21 years' follow-up. A random population sample of 750 men, all 50 years of age, was examined in 1993. Endpoints were retrieved 21 years later at 71 years of age. Albumin-corrected serum (S) calcium, S-25-hydroxyvitamin D and S-PTH were assessed along with data on cardiovascular risk factors and medication. Outcome data on fractures, stroke, myocardial infarction, cancer and death were retrieved in 2014; 21 years after primary assessment. The prevalence of HPT at 50 years of age was 9.3%; nHPT 2.8%, primary HPT 0.4%, secondary HPT 0.4%, and HPT with vitamin D insufficiency 6%. Fracture rate, myocardial infarction, stroke, cancer and death occurred similarly in men with or without HPT, as well as in men with nHPT as compared with men without calcium/PTH aberrations during 21 years' follow-up. S-PTH was evenly distributed in the univariable analyses for each outcome. Cox regression analyses showed no increase in serious morbidity or in mortality in men with HPT, irrespective of cause, compared with men with normal S-PTH over a 21-year period. None had HPT at a S-25(OH)D level of 100 nmol/L.
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