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- Ekhtiari, Hamed, et al.
(författare)
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A methodological checklist for fMRI drug cue reactivity studies : development and expert consensus
- 2022
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Ingår i: Nature Protocols. - : Nature Portfolio. - 1754-2189 .- 1750-2799. ; 17:3, s. 567-595
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Tidskriftsartikel (refereegranskat)abstract
- Cue reactivity measured by functional magnetic resonance imaging is used in studies of substance-use disorders. This Consensus Statement is the result of a Delphi process to arrive at parameters that should be reported in describing these studies. Cue reactivity is one of the most frequently used paradigms in functional magnetic resonance imaging (fMRI) studies of substance use disorders (SUDs). Although there have been promising results elucidating the neurocognitive mechanisms of SUDs and SUD treatments, the interpretability and reproducibility of these studies is limited by incomplete reporting of participants characteristics, task design, craving assessment, scanning preparation and analysis decisions in fMRI drug cue reactivity (FDCR) experiments. This hampers clinical translation, not least because systematic review and meta-analysis of published work are difficult. This consensus paper and Delphi study aims to outline the important methodological aspects of FDCR research, present structured recommendations for more comprehensive methods reporting and review the FDCR literature to assess the reporting of items that are deemed important. Forty-five FDCR scientists from around the world participated in this study. First, an initial checklist of items deemed important in FDCR studies was developed by several members of the Enhanced NeuroImaging Genetics through Meta-Analyses (ENIGMA) Addiction working group on the basis of a systematic review. Using a modified Delphi consensus method, all experts were asked to comment on, revise or add items to the initial checklist, and then to rate the importance of each item in subsequent rounds. The reporting status of the items in the final checklist was investigated in 108 recently published FDCR studies identified through a systematic review. By the final round, 38 items reached the consensus threshold and were classified under seven major categories: Participants Characteristics, General fMRI Information, General Task Information, Cue Information, Craving Assessment Inside Scanner, Craving Assessment Outside Scanner and Pre- and Post-Scanning Considerations. The review of the 108 FDCR papers revealed significant gaps in the reporting of the items considered important by the experts. For instance, whereas items in the General fMRI Information category were reported in 90.5% of the reviewed papers, items in the Pre- and Post-Scanning Considerations category were reported by only 44.7% of reviewed FDCR studies. Considering the notable and sometimes unexpected gaps in the reporting of items deemed to be important by experts in any FDCR study, the protocols could benefit from the adoption of reporting standards. This checklist, a living document to be updated as the field and its methods advance, can help improve experimental design, reporting and the widespread understanding of the FDCR protocols. This checklist can also provide a sample for developing consensus statements for protocols in other areas of task-based fMRI.
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2. |
- Craddock, Nick, et al.
(författare)
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Genome-wide association study of CNVs in 16,000 cases of eight common diseases and 3,000 shared controls
- 2010
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 464:7289, s. 713-720
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Tidskriftsartikel (refereegranskat)abstract
- Copy number variants (CNVs) account for a major proportion of human genetic polymorphism and have been predicted to have an important role in genetic susceptibility to common disease. To address this we undertook a large, direct genome-wide study of association between CNVs and eight common human diseases. Using a purpose-designed array we typed,19,000 individuals into distinct copy-number classes at 3,432 polymorphic CNVs, including an estimated similar to 50% of all common CNVs larger than 500 base pairs. We identified several biological artefacts that lead to false-positive associations, including systematic CNV differences between DNAs derived from blood and cell lines. Association testing and follow-up replication analyses confirmed three loci where CNVs were associated with disease-IRGM for Crohn's disease, HLA for Crohn's disease, rheumatoid arthritis and type 1 diabetes, and TSPAN8 for type 2 diabetes-although in each case the locus had previously been identified in single nucleotide polymorphism (SNP)-based studies, reflecting our observation that most common CNVs that are well-typed on our array are well tagged by SNPs and so have been indirectly explored through SNP studies. We conclude that common CNVs that can be typed on existing platforms are unlikely to contribute greatly to the genetic basis of common human diseases.
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3. |
- Martinez-Sanz, Marta, et al.
(författare)
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Advanced structural characterisation of agar-based hydrogels : Rheological and small angle scattering studies
- 2020
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Ingår i: Carbohydrate Polymers. - : Elsevier BV. - 0144-8617 .- 1879-1344. ; 236
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Tidskriftsartikel (refereegranskat)abstract
- Agar-based extracts from Gelidium sesquipedale were generated by heat and combined heat-sonication, with and without the application of alkali pre-treatment. Pre-treatment yielded extracts with greater agar contents; however, it produced partial degradation of the agar, reducing its molecular weight. Sonication produced extracts with lower agar contents and decreased molecular weights. A gelation mechanism is proposed based on the rheological and small angle scattering characterization of the extracts. The formation of strong hydrogels upon cooling was caused by the association of agarose chains into double helices and bundles, the sizes of which depended on the agar purity and molecular weight. These different arrangements at the molecular scale consequently affected the mechanical performance of the obtained hydrogels. Heating of the hydrogels produced a gradual disruption of the bundles; weaker or smaller bundles were formed upon subsequent cooling, suggesting that the process was not completely reversible.
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12. |
- Chye, Yann, et al.
(författare)
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Subcortical surface morphometry in substance dependence : An ENIGMA addiction working group study
- 2020
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Ingår i: Addiction Biology. - : WILEY. - 1355-6215 .- 1369-1600. ; 25:6
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Tidskriftsartikel (refereegranskat)abstract
- While imaging studies have demonstrated volumetric differences in subcortical structures associated with dependence on various abused substances, findings to date have not been wholly consistent. Moreover, most studies have not compared brain morphology across those dependent on different substances of abuse to identify substance-specific and substance-general dependence effects. By pooling large multinational datasets from 33 imaging sites, this study examined subcortical surface morphology in 1628 nondependent controls and 2277 individuals with dependence on alcohol, nicotine, cocaine, methamphetamine, and/or cannabis. Subcortical structures were defined by FreeSurfer segmentation and converted to a mesh surface to extract two vertex-level metrics-the radial distance (RD) of the structure surface from a medial curve and the log of the Jacobian determinant (JD)-that, respectively, describe local thickness and surface area dilation/contraction. Mega-analyses were performed on measures of RD and JD to test for the main effect of substance dependence, controlling for age, sex, intracranial volume, and imaging site. Widespread differences between dependent users and nondependent controls were found across subcortical structures, driven primarily by users dependent on alcohol. Alcohol dependence was associated with localized lower RD and JD across most structures, with the strongest effects in the hippocampus, thalamus, putamen, and amygdala. Meanwhile, nicotine use was associated with greater RD and JD relative to nonsmokers in multiple regions, with the strongest effects in the bilateral hippocampus and right nucleus accumbens. By demonstrating subcortical morphological differences unique to alcohol and nicotine use, rather than dependence across all substances, results suggest substance-specific relationships with subcortical brain structures.
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13. |
- Dang, Junhua, et al.
(författare)
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A Multilab Replication of the Ego Depletion Effect
- 2021
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Ingår i: Social Psychology and Personality Science. - : Sage Publications. - 1948-5506 .- 1948-5514. ; 12:1, s. 14-24
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Tidskriftsartikel (refereegranskat)abstract
- There is an active debate regarding whether the ego depletion effect is real. A recent preregistered experiment with the Stroop task as the depleting task and the antisaccade task as the outcome task found a medium-level effect size. In the current research, we conducted a preregistered multilab replication of that experiment. Data from 12 labs across the globe (N = 1,775) revealed a small and significant ego depletion effect, d = 0.10. After excluding participants who might have responded randomly during the outcome task, the effect size increased to d = 0.16. By adding an informative, unbiased data point to the literature, our findings contribute to clarifying the existence, size, and generality of ego depletion.
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14. |
- Eccleston, Christopher, et al.
(författare)
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Pharmacological interventions for chronic pain in children : an overview of systematic reviews
- 2019
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Ingår i: Pain. - : Ovid Technologies (Wolters Kluwer Health). - 0304-3959 .- 1872-6623. ; 160:8, s. 1698-1707
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Forskningsöversikt (refereegranskat)abstract
- We know little about the safety or efficacy of pharmacological medicines for children and adolescents with chronic pain, despite their common use. Our aim was to conduct an overview review of systematic reviews of pharmacological interventions that purport to reduce pain in children with chronic noncancer pain (CNCP) or chronic cancer-related pain (CCRP). We searched the Cochrane Database of Systematic Reviews, Medline, EMBASE, and DARE for systematic reviews from inception to March 2018. We conducted reference and citation searches of included reviews. We included children (0-18 years of age) with CNCP or CCRP. We extracted the review characteristics and primary outcomes of >= 30% participant-reported pain relief and patient global impression of change. We sifted 704 abstracts and included 23 systematic reviews investigating children with CNCP or CCRP. Seven of those 23 reviews included 6 trials that involved children with CNCP. There were no randomised controlled trials in reviews relating to reducing pain in CCRP. We were unable to combine data in a meta-analysis. Overall, the quality of evidence was very low, and we have very little confidence in the effect estimates. The state of evidence of randomized controlled trials in this field is poor; we have no evidence from randomised controlled trials for pharmacological interventions in children with cancer-related pain, yet cannot deny individual children access to potential pain relief.
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15. |
- Elliot, Anders H., et al.
(författare)
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An audit of performance, interpretation, and influence of pretherapeutic MRI in rectal cancer : a Swedish population-based cohort study
- 2019
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Ingår i: Acta Radiologica. - : SAGE PUBLICATIONS LTD. - 0284-1851 .- 1600-0455. ; 60:8, s. 955-961
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Tidskriftsartikel (refereegranskat)abstract
- Background: The performance of magnetic resonance imaging (MRI) interpretation and communication of findings and its implication on treatment decisions has not fully been explored in rectal cancer.Purpose: To investigate in a region the adherence to MRI protocol standards and the relation between MRI interpretation and selection to preoperative therapy in rectal cancer.Material and Methods: Data on consecutive patients who underwent elective rectal cancer surgery in the region from January to June 2010 were obtained from the National Colorectal Cancer Registry. Pretherapeutic MRI images were re-evaluated. Agreement between the original reports and the re-evaluation was compared using Cohen's kappa coefficient.Results: Among the 94 patients included, 81 (86%) had pretherapeutic MRI in accordance with defined imaging guidelines. In 34% of the original MR reports, data on extramural venous invasion (mrEMVI) and mrT category were not reported. Complete tumor staging was not possible because of missing data in 33 (35%) of the patients. The agreement between the original MR reports and the re-evaluation regarding tumor stage was moderate (kappa = 0.48). For decided treatment compared to recommended preoperative treatment according to the re-evaluation, the agreement was fair (kappa = 0.33).Conclusion: Established MRI protocol standards were not universally applied. Missing data and inadequacies in original MRI reports resulted in moderate agreement between the original report and the re-evaluation indicating a risk of inappropriate treatment selection. The results call for further educational efforts in rectal cancer MRI acquisition and repeated audits of image protocol adherence and interpretation quality.
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16. |
- Elliot, Anders H., et al.
(författare)
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Pretreatment MRI in Primary Rectal Cancer as a Predictor for Oncological Outcomes After Surgery for Local Recurrence
- 2021
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Ingår i: Anticancer Research. - : Anticancer Research USA Inc.. - 0250-7005 .- 1791-7530. ; 41:5, s. 2459-2465
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Tidskriftsartikel (refereegranskat)abstract
- Background/Aim: For patients with locally recurrent rectal cancer (LRRC) extensive surgery is often the only curative option and patient selection is crucial. This study aimed to investigate whether magnetic resonance imaging (MRI) characteristics of the primary tumour can predict oncological outcome after surgery for locally recurrent rectal cancer (LRRC). Patients andMethods: All patients undergoing surgery for LRRC with a curative intent at the Karolinska University Hospital 2003-2013 were included. MRI examinations of the primary tumour were re-evaluated.Results: In total, 54 patients were included. A tumour volume decrease of <70% after preoperative radiotherapy or chemoradiotherapy (C)RT for the primary tumour was correlated with a lower proportion of R0 resection of the LRRC (OR=0.07, 95% CI=0.01-0.84). No association between MRI characteristics of the primary tumour and prognosis after LRRC surgery was found.Conclusion: Long-term outcomes after surgery for LRRC were not significantly associated with MRI characteristics of the index tumour. However, factors associated with increased risk of R1 resection of LRRC were identified.
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17. |
- Elliot, Viktor, et al.
(författare)
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Bankboken: hur banker fungerar, drivs och regleras
- 2019
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- Att kanalisera pengar mellan de som har pengar att avvara och de som behöver låna har varit en nyckelfunktion för banker i många hundra år och kommer sannolikt att förbli så under en överskådlig framtid. I Bankboken behandlas hur moderna banker styrs och regleras, vilka rapportkrav de omfattas av och hur riskhanteringen organiseras och utformas. Boken innehåller utförliga beskrivningar av de många bankspecifika begrepp som förekommer inom bankbranschen och sätter dem i sitt sammanhang. Med avstamp i bankens historia åskådliggörs hur banker omformats från små, enkla företag till stora finansiella varuhus som idag utmanas av digitalisering och en allt striktare reglering. Andra områden som diskuteras är bland annat: • hur den tekniska utvecklingen inverkar på banker och vilka effekter den kan tänkas ha på bankernas roll i framtiden • vikten av att särskilja mellan banker och de människor som arbetar där • bankernas roll i samhället och varför de behövs som ett smörjmedel i ekonomin. Bankboken är avsedd för dig som vill skaffa dig en bättre förståelse för varför banker finns, hur de fungerar och hur modern bankverksamhet organiseras, styrs och regleras.
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18. |
- Elliot, Viktor, et al.
(författare)
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National implications of EU harmonization - The case of banks' reporting requirements in Sweden
- 2019
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The purpose of this paper is to discuss how internationally formulated policies and regulation of banks affect national supervisory practices and what consequences this may have on the form and quality of banking supervision conducted on the national level. Using the case of Swedish banks’ reporting requirements, we argue that the last decade of EU level regulatory reforms are motivated by a different “regulatory agreement” (Young 2016) than the Swedish one. In the decade since the global financial crisis 2007-2009, banking regulation reforms appear to be shaped by a view that all financial institutions are more or less immoral and cannot be trusted to self-regulate. The development can be characterized as a move from a dialogue based relationship between the supervisor and the supervised (Roberts, 2009) and being based on fairly high levels of trust (Tomkins, 2001), to a more quantitative and centralized supervision based on collection and comparison of large amounts of standardized quantitative data. We argue that Swedish financial regulation and supervision traditionally were based on the notion of dialogue and mutual trust and less on extensive reporting requirements. Thus, for Sweden to conform to the post-crisis international regulatory framework, this means abandoning what appears to be a fairly well-functioning national arrangement.
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19. |
- Hou, Liping, et al.
(författare)
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Genome-wide association study of 40,000 individuals identifies two novel loci associated with bipolar disorder.
- 2016
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Ingår i: Human molecular genetics. - : Oxford University Press (OUP). - 1460-2083 .- 0964-6906. ; 25:15, s. 3383-94
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Tidskriftsartikel (refereegranskat)abstract
- Bipolar disorder (BD) is a genetically complex mental illness characterized by severe oscillations of mood and behavior. Genome-wide association studies (GWAS) have identified several risk loci that together account for a small portion of the heritability. To identify additional risk loci, we performed a two-stage meta-analysis of >9 million genetic variants in 9,784 bipolar disorder patients and 30,471 controls, the largest GWAS of BD to date. In this study, to increase power we used ∼2,000 lithium-treated cases with a long-term diagnosis of BD from the Consortium on Lithium Genetics, excess controls, and analytic methods optimized for markers on the X-chromosome. In addition to four known loci, results revealed genome-wide significant associations at two novel loci: an intergenic region on 9p21.3 (rs12553324, p=5.87×10(-9); odds ratio=1.12) and markers within ERBB2 (rs2517959, p=4.53×10(-9); odds ratio=1.13). No significant X-chromosome associations were detected and X-linked markers explained very little BD heritability. The results add to a growing list of common autosomal variants involved in BD and illustrate the power of comparing well-characterized cases to an excess of controls in GWAS.
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20. |
- Jelenkovic, Aline, et al.
(författare)
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Zygosity Differences in Height and Body Mass Index of Twins From Infancy to Old Age : A Study of the CODATwins Project
- 2015
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Ingår i: Twin Research and Human Genetics. - : Cambridge University Press. - 1832-4274 .- 1839-2628. ; 18:5, s. 557-570
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Tidskriftsartikel (refereegranskat)abstract
- A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), and included 842,951 height and BMI measurements from twins aged 1 to 102 years. The results showed that DZ twins were consistently taller than MZ twins, with differences of up to 2.0 cm in childhood and adolescence and up to 0.9 cm in adulthood. Similarly, a greater mean BMI of up to 0.3 kg/m(2) in childhood and adolescence and up to 0.2 kg/m(2) in adulthood was observed in DZ twins, although the pattern was less consistent. DZ twins presented up to 1.7% greater height and 1.9% greater BMI than MZ twins; these percentage differences were largest in middle and late childhood and decreased with age in both sexes. The variance of height was similar in MZ and DZ twins at most ages. In contrast, the variance of BMI was significantly higher in DZ than in MZ twins, particularly in childhood. In conclusion, DZ twins were generally taller and had greater BMI than MZ twins, but the differences decreased with age in both sexes.
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21. |
- Jon-And, Anna, 1976-, et al.
(författare)
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A model of contact-induced language change : Testing the role of second language speakers in the evolution of Mozambican Portuguese
- 2019
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 14:4
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Tidskriftsartikel (refereegranskat)abstract
- Language change is accelerated by language contact, especially by contact that occurs when a group of speakers shifts from one language to another. This has commonly been explained by linguistic innovation occurring during second language acquisition. This hypothesis is based on historical reconstructions of instances of contact and has not been formally tested on empirical data. In this paper, we construct an agent-based model to formalize the hypothesis that second language speakers are responsible for accelerated language change during language shift. We compare model predictions to a unique combination of diachronic linguistic and demographic data from Maputu, Mozambique. The model correctly predicts an increased proportional use of the novel linguistic variants during the period we study. We find that a modified version of the model is a better fit to one of our two datasets and discuss plausible reasons for this. As a general conclusion concerning typological differences between contact-induced and non-contact-induced language change, we suggest that multiple introductions of a new linguistic variant by different individuals may be the mechanism by which language contact accelerates language change.
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- Jon-And, Anna, 1976-, et al.
(författare)
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Modelling contact-induced language change in Angolan Portuguese
- 2014
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Konferensbidrag (refereegranskat)abstract
- In this paper we present a model for simulating language change in an expanding speech population using evolutionary game theory, in order to comment on earlier assumptions about linguistic transmission and change in language shift situations. It has largely been assumed that when a group shifts from one language to another, first generation second language (L2) speakers introduce the changes that are stabilized in the second generation of first language (L1) speakers (Fishman 1991: 9; Thomason and Kaufman 1988). Our empirical point of departure is the ongoing language shift from Bantu languages to Portuguese in Angola, which has occurred mainly after independence in 1974. We believe that a realistic model for linguistic innovation and spread needs to include transmission within generations as well as between them and should consider interaction between L1 and L2 varieties. Our computational model attempts to simulate the growth of the Portuguese speaking population in Angola since 1974, as well as the introduction and spread of a possibly contact related linguistic variant (using omission of preposition in locative phrases as an example). The population grows by recruitment of L2 speakers and birth of L1 speakers. For the linguistic feature the simulation starts with the original variant fixed. We add the probability of some individuals introducing the new variant and then allow individuals to interact and update their probabilities of using one variant or the other. By varying the weight for different kinds of interactions and population growth rates for L1 and L2 speakers, the simulation enables us to formalize hypotheses concerning the conditions required for the spread of the new linguistic variant. The outcomes of the simulations will later be compared to data from Cabinda in northern Angola that will be collected in June 2014.Preliminary results indicate that at least one of the following two conditions needs to be fulfilled for a variant introduced by L2 speakers to spread: (i) recruitment rate of L2 speakers exceeds birth rate for L1 speakers; (ii) L1 speakers are equally influenced by interactions with L2 and L1 speakers. If birth rate of L1 speakers exceeds recruitment rate for L2 speakers and L1 speakers are less influenced by interaction with L2 speakers than with L1 speakers, the new variant does not spread in the population.
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26. |
- Nandadasa, Sumeda, et al.
(författare)
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Vascular dimorphism ensured by regulated proteoglycan dynamics favors rapid umbilical artery closure at birth
- 2020
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Ingår i: eLife. - 2050-084X. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- The umbilical artery lumen closes rapidly at birth, preventing neonatal blood loss, whereas the umbilical vein remains patent longer. Here, analysis of umbilical cords from humans and other mammals identified differential arterial-venous proteoglycan dynamics as a determinant of these contrasting vascular responses. The umbilical artery, but not the vein, has an inner layer enriched in the hydrated proteoglycan aggrecan, external to which lie contraction-primed smooth muscle cells (SMC). At birth, SMC contraction drives inner layer buckling and centripetal displacement to occlude the arterial lumen, a mechanism revealed by biomechanical observations and confirmed by computational analyses. This vascular dimorphism arises from spatially regulated proteoglycan expression and breakdown. Mice lacking aggrecan or the metalloprotease ADAMTS1, which degrades proteoglycans, demonstrate their opposing roles in umbilical vascular dimorphism, including effects on SMC differentiation. Umbilical vessel dimorphism is conserved in mammals, suggesting that differential proteoglycan dynamics and inner layer buckling were positively selected during evolution.
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27. |
- Silventoinen, Karri, et al.
(författare)
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Education in twins and their parents across birth cohorts over 100 years : an individual-level pooled analysis of 42 twin cohorts
- 2017
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Ingår i: Twin Research and Human Genetics. - Stockholm : Karolinska Institutet, Dept of Medical Epidemiology and Biostatistics. - 1832-4274 .- 1839-2628.
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Tidskriftsartikel (refereegranskat)abstract
- Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990-1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
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28. |
- Silventoinen, Karri, et al.
(författare)
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The CODATwins Project : The Cohort Description of Collaborative Project of Development of Anthropometrical Measures in Twins to Study Macro-Environmental Variation in Genetic and Environmental Effects on Anthropometric Traits
- 2015
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Ingår i: Twin Research and Human Genetics. - : Cambridge University Press. - 1832-4274 .- 1839-2628. ; 18:4
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Tidskriftsartikel (refereegranskat)abstract
- For over 100 years, the genetics of human anthropometric traits has attracted scientific interest. In particular, height and body mass index (BMI, calculated as kg/m2) have been under intensive genetic research. However, it is still largely unknown whether and how heritability estimates vary between human populations. Opportunities to address this question have increased recently because of the establishment of many new twin cohorts and the increasing accumulation of data in established twin cohorts. We started a new research project to analyze systematically (1) the variation of heritability estimates of height, BMI and their trajectories over the life course between birth cohorts, ethnicities and countries, and (2) to study the effects of birth-related factors, education and smoking on these anthropometric traits and whether these effects vary between twin cohorts. We identified 67 twin projects, including both monozygotic (MZ) and dizygotic (DZ) twins, using various sources. We asked for individual level data on height and weight including repeated measurements, birth related traits, background variables, education and smoking. By the end of 2014, 48 projects participated. Together, we have 893,458 height and weight measures (52% females) from 434,723 twin individuals, including 201,192 complete twin pairs (40% monozygotic, 40% same-sex dizygotic and 20% opposite-sex dizygotic) representing 22 countries. This project demonstrates that large-scale international twin studies are feasible and can promote the use of existing data for novel research purposes.
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29. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Physical Review C (Nuclear Physics). - 0556-2813 .- 1089-490X. ; 92:3
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Tidskriftsartikel (refereegranskat)
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30. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; :8
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Tidskriftsartikel (refereegranskat)
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31. |
- Aad, G., et al.
(författare)
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- 2015
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Tidskriftsartikel (refereegranskat)
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