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| 2. |
- Zouganelis, I., et al.
(författare)
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The Solar Orbiter Science Activity Plan : Translating solar and heliospheric physics questions into action
- 2020
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Ingår i: Astronomy and Astrophysics. - : EDP SCIENCES S A. - 0004-6361 .- 1432-0746. ; 642
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Tidskriftsartikel (refereegranskat)abstract
- Solar Orbiter is the first space mission observing the solar plasma both in situ and remotely, from a close distance, in and out of the ecliptic. The ultimate goal is to understand how the Sun produces and controls the heliosphere, filling the Solar System and driving the planetary environments. With six remote-sensing and four in-situ instrument suites, the coordination and planning of the operations are essential to address the following four top-level science questions: (1) What drives the solar wind and where does the coronal magnetic field originate?; (2) How do solar transients drive heliospheric variability?; (3) How do solar eruptions produce energetic particle radiation that fills the heliosphere?; (4) How does the solar dynamo work and drive connections between the Sun and the heliosphere? Maximising the mission's science return requires considering the characteristics of each orbit, including the relative position of the spacecraft to Earth (affecting downlink rates), trajectory events (such as gravitational assist manoeuvres), and the phase of the solar activity cycle. Furthermore, since each orbit's science telemetry will be downloaded over the course of the following orbit, science operations must be planned at mission level, rather than at the level of individual orbits. It is important to explore the way in which those science questions are translated into an actual plan of observations that fits into the mission, thus ensuring that no opportunities are missed. First, the overarching goals are broken down into specific, answerable questions along with the required observations and the so-called Science Activity Plan (SAP) is developed to achieve this. The SAP groups objectives that require similar observations into Solar Orbiter Observing Plans, resulting in a strategic, top-level view of the optimal opportunities for science observations during the mission lifetime. This allows for all four mission goals to be addressed. In this paper, we introduce Solar Orbiter's SAP through a series of examples and the strategy being followed.
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| 3. |
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| 4. |
- Pelletier, F., et al.
(författare)
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Endocrine and Growth Abnormalities in 4H Leukodystrophy Caused by Variants in POLR3A, POLR3B, and POLR1C
- 2021
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Ingår i: Journal of Clinical Endocrinology & Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 106:2
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Tidskriftsartikel (refereegranskat)abstract
- Context: 4H or POLR3-related leukodystrophy is an autosomal recessive disorder typically characterized by hypomyelination, hypodontia, and hypogonadotropic hypogonadism, caused by biallelic pathogenic variants in POLR3A, POLR3B, POLR1C, and POLR3K. The endocrine and growth abnormalities associated with this disorder have not been thoroughly investigated to date. Objective: To systematically characterize endocrine abnormalities of patients with 4H leukodystrophy. Design: An international cross-sectional study was performed on 150 patients with genetically confirmed 4H leukodystrophy between 2015 and 2016. Endocrine and growth abnormalities were evaluated, and neurological and other non-neurological features were reviewed. Potential genotype/phenotype associations were also investigated. Setting: This was a multicenter retrospective study using information collected from 3 predominant centers. Patients: A total of 150 patients with 4H leukodystrophy and pathogenic variants in POLR3A, POLR3B, or POLR1C were included. Main Outcome Measures: Variables used to evaluate endocrine and growth abnormalities included pubertal history, hormone levels (estradiol, testosterone, stimulated LH and FSH, stimulated GH, IGF-I, prolactin, ACTH, cortisol, TSH, and T4), and height and head circumference charts. Results: The most common endocrine abnormalities were delayed puberty (57/74; 77% overall, 64% in males, 89% in females) and short stature (57/93; 61%), when evaluated according to physician assessment. Abnormal thyroid function was reported in 22% (13/59) of patients. Conclusions: Our results confirm pubertal abnormalities and short stature are the most common endocrine features seen in 4H leukodystrophy. However, we noted that endocrine abnormalities are typically underinvestigated in this patient population. A prospective study is required to formulate evidence-based recommendations for management of the endocrine manifestations of this disorder.
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| 5. |
- Brownstein, Catherine A., et al.
(författare)
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An international effort towards developing standards for best practices in analysis, interpretation and reporting of clinical genome sequencing results in the CLARITY Challenge
- 2014
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Ingår i: Genome Biology. - : Springer Science and Business Media LLC. - 1465-6906 .- 1474-760X. ; 15:3, s. R53-
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Tidskriftsartikel (refereegranskat)abstract
- Background: There is tremendous potential for genome sequencing to improve clinical diagnosis and care once it becomes routinely accessible, but this will require formalizing research methods into clinical best practices in the areas of sequence data generation, analysis, interpretation and reporting. The CLARITY Challenge was designed to spur convergence in methods for diagnosing genetic disease starting from clinical case history and genome sequencing data. DNA samples were obtained from three families with heritable genetic disorders and genomic sequence data were donated by sequencing platform vendors. The challenge was to analyze and interpret these data with the goals of identifying disease-causing variants and reporting the findings in a clinically useful format. Participating contestant groups were solicited broadly, and an independent panel of judges evaluated their performance. Results: A total of 30 international groups were engaged. The entries reveal a general convergence of practices on most elements of the analysis and interpretation process. However, even given this commonality of approach, only two groups identified the consensus candidate variants in all disease cases, demonstrating a need for consistent fine-tuning of the generally accepted methods. There was greater diversity of the final clinical report content and in the patient consenting process, demonstrating that these areas require additional exploration and standardization. Conclusions: The CLARITY Challenge provides a comprehensive assessment of current practices for using genome sequencing to diagnose and report genetic diseases. There is remarkable convergence in bioinformatic techniques, but medical interpretation and reporting are areas that require further development by many groups.
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| 7. |
- Bayley, PJ, et al.
(författare)
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2013 SYR Accepted Poster Abstracts
- 2013
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Ingår i: International journal of yoga therapy. - 1531-2054. ; 23:1, s. 32-53
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Tidskriftsartikel (refereegranskat)
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| 8. |
- Buch, S., et al.
(författare)
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Genetic variation in TERT modifies the risk of hepatocellular carcinoma in alcohol-related cirrhosis: results from a genome-wide case-control study
- 2023
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Ingår i: Gut. - : BMJ. - 0017-5749 .- 1468-3288. ; 72:2, s. 381-391
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Tidskriftsartikel (refereegranskat)abstract
- Objective Hepatocellular carcinoma (HCC) often develops in patients with alcohol-related cirrhosis at an annual risk of up to 2.5%. Some host genetic risk factors have been identified but do not account for the majority of the variance in occurrence. This study aimed to identify novel susceptibility loci for the development of HCC in people with alcohol related cirrhosis. Design Patients with alcohol-related cirrhosis and HCC (cases: n=1214) and controls without HCC (n=1866), recruited from Germany, Austria, Switzerland, Italy and the UK, were included in a two-stage genome-wide association study using a case-control design. A validation cohort of 1520 people misusing alcohol but with no evidence of liver disease was included to control for possible association effects with alcohol misuse. Genotyping was performed using the InfiniumGlobal Screening Array (V.24v2, Illumina) and the OmniExpress Array (V.24v1-0a, Illumina). Results Associations with variants rs738409 in PNPLA3 and rs58542926 in TM6SF2 previously associated with an increased risk of HCC in patients with alcohol-related cirrhosis were confirmed at genome-wide significance. A novel locus rs2242652(A) in TERT (telomerase reverse transcriptase) was also associated with a decreased risk of HCC, in the combined meta-analysis, at genome-wide significance (p=6.41x10(-9), OR=0.61 (95% CI 0.52 to 0.70). This protective association remained significant after correction for sex, age, body mass index and type 2 diabetes (p=7.94x10(-5), OR=0.63 (95% CI 0.50 to 0.79). Carriage of rs2242652(A) in TERT was associated with an increased leucocyte telomere length (p=2.12x10(-44)). Conclusion This study identifies rs2242652 in TERT as a novel protective factor for HCC in patients with alcohol-related cirrhosis.
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| 9. |
- Boxall, A. B. A., et al.
(författare)
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Pharmaceuticals and Personal Care Products in the Environment: What Are the Big Questions?
- 2012
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Ingår i: Environmental Health Perspectives. - : Environmental Health Perspectives. - 0091-6765 .- 1552-9924. ; 120:9, s. 1221-1229
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Over the past 10-15 years, a substantial amount of work has been done by the scientific, regulatory, and business communities to elucidate the effects and risks of pharmaceuticals and personal care products (PPCPs) in the environment. OBJECTIVE: This review was undertaken to identify key outstanding issues regarding the effects of PPCPs on human and ecological health in order to ensure that future resources will be focused on the most important areas. DATA SOURCES: To better understand and manage the risks of PPCPs in the environment, we used the "key question" approach to identify the principle issues that need to be addressed. Initially, questions were solicited from academic, government, and business communities around the world. A list of 101 questions was then discussed at an international expert workshop, and a top-20 list was developed. Following the workshop, workshop attendees ranked the 20 questions by importance. DATA SYNTHESIS: The top 20 priority questions fell into seven categories: a) prioritization of substances for assessment, b) pathways of exposure, c) bioavailability and uptake, a effects characterization, e) risk and relative risk, f) antibiotic resistance, and g) risk management. CONCLUSIONS: A large body of information is now available on PPCPs in the environment. This exercise prioritized the most critical questions to aid in development of future research programs on the topic.
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| 14. |
- Horsley, A R, et al.
(författare)
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Lung clearance index is a sensitive, repeatable and practical measure of airways disease in adults with cystic fibrosis.
- 2008
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Ingår i: Thorax. - : BMJ. - 1468-3296 .- 0040-6376. ; 63:2, s. 135-40
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Lung clearance index (LCI) is a sensitive marker of early lung disease in children but has not been assessed in adults. Measurement is hindered by the complexity of the equipment required. The aims of this study were to assess performance of a novel gas analyser (Innocor) and to use it as a clinical tool for the measurement of LCI in cystic fibrosis (CF). METHODS: LCI was measured in 48 healthy adults, 12 healthy school-age children and 33 adults with CF by performing an inert gas washout from 0.2% sulfur hexafluoride (SF6). SF6 signal:noise ratio and 10-90% rise time of Innocor were compared with a mass spectrometer used in similar studies in children. RESULTS: Compared with the mass spectrometer, Innocor had a superior signal:noise ratio but a slower rise time (150 ms vs 60 ms) which may limit its use in very young children. Mean (SD) LCI in healthy adults was significantly different from that in patients with CF: 6.7 (0.4) vs 13.1 (3.8), p<0.001. Ten of the patients with CF had forced expiratory volume in 1 s > or = 80% predicted but only one had a normal LCI. LCI repeats were reproducible in all three groups of subjects (mean intra-visit coefficient of variation ranged from 3.6% to 5.4%). CONCLUSIONS: Innocor can be adapted to measure LCI and affords a simpler alternative to a mass spectrometer. LCI is raised in adults with CF with normal spirometry, and may prove to be a more sensitive marker of the effects of treatment in this group.
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| 15. |
- Sandercock, P, et al.
(författare)
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Update on the third international stroke trial (IST-3) of thrombolysis for acute ischaemic stroke and baseline features of the 3035 patients recruited
- 2011
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Ingår i: Trials. - : Springer Science and Business Media LLC. - 1745-6215. ; 12, s. 252-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:Intravenous recombinant tissue plasminogen activator (rtPA) is approved in Europe for use in patients with acute ischaemic stroke who meet strictly defined criteria. IST-3 sought to improve the external validity and prediction of the estimates of the overall treatment effects (efficacy and safety) of rtPA in acute ischaemic stroke, and to determine whether a wider range of patients might benefit.DESIGN:International, multi-centre, prospective, randomized, open, blinded endpoint (PROBE) trial of intravenous rtPA in acute ischaemic stroke. Suitable patients had to be assessed and able to start treatment within 6 hours of developing symptoms, and brain imaging must have excluded intracranial haemorrhage and stroke mimics.RESULTS:The initial pilot phase was double blind and then, on 01/08/2003, changed to an open design. Recruitment began on 05/05/2000 and closed on 31/07/2011, by which time 3035 patients had been included, only 61 (2%) of whom met the criteria for the 2003 European approval for thrombolysis. 1617 patients were aged over 80 years at trial entry. The analysis plan will be finalised, without reference to the unblinded data, and published before the trial data are unblinded in early 2012. The main trial results will be presented at the European Stroke Conference in Lisbon in May 2012 with the aim to publish simultaneously in a peer-reviewed journal. The trial result will be presented in the context of an updated Cochrane systematic review. We also intend to include the trial data in an individual patient data meta-analysis of all the relevant randomised trials.CONCLUSION:The data from the trial will: improve the external validity and prediction of the estimates of the overall treatment effects (efficacy and safety) of iv rtPA in acute ischaemic stroke; provide: new evidence on the balance of risk and benefit of intravenous rtPA among types of patients who do not clearly meet the terms of the current EU approval; and, provide the first large-scale randomised evidence on effects in patients over 80, an age group which had largely been excluded from previous acute stroke trials. Trial registration ISRCTN25765518.
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| 16. |
- Ashfield, T., et al.
(författare)
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Evolution of a Complex Disease Resistance Gene Cluster in Diploid Phaseolus and Tetraploid Glycine
- 2012
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Ingår i: Plant Physiology. - 0032-0889 .- 1532-2548. ; 159:1, s. 336-354
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Tidskriftsartikel (refereegranskat)abstract
- We used a comparative genomics approach to investigate the evolution of a complex nucleotide-binding (NB)-leucine-rich repeat (LRR) gene cluster found in soybean (Glycine max) and common bean (Phaseolus vulgaris) that is associated with several disease resistance (R) genes of known function, including Rpg1b (for Resistance to Pseudomonas glycinea1b), an R gene effective against specific races of bacterial blight. Analysis of domains revealed that the amino-terminal coiled-coil (CC) domain, central nucleotide-binding domain (NB-ARC [for APAF1, Resistance genes, and CED4]), and carboxyl-terminal LRR domain have undergone distinct evolutionary paths. Sequence exchanges within the NB-ARC domain were rare. In contrast, interparalogue exchanges involving the CC and LRR domains were common, consistent with both of these regions coevolving with pathogens. Residues under positive selection were overrepresented within the predicted solvent-exposed face of the LRR domain, although several also were detected within the CC and NB-ARC domains. Superimposition of these latter residues onto predicted tertiary structures revealed that the majority are located on the surface, suggestive of a role in interactions with other domains or proteins. Following polyploidy in the Glycine lineage, NB-LRR genes have been preferentially lost from one of the duplicated chromosomes (homeologues found in soybean), and there has been partitioning of NB-LRR clades between the two homeologues. The single orthologous region in common bean contains approximately the same number of paralogues as found in the two soybean homeologues combined. We conclude that while polyploidization in Glycine has not driven a stable increase in family size for NB-LRR genes, it has generated two recombinationally isolated clusters, one of which appears to be in the process of decay.
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| 17. |
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| 18. |
- Kenigsberg, PA, et al.
(författare)
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Assistive Technologies to Address Capabilities of People with Dementia: From Research to Practice
- 2019
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Ingår i: Dementia (London, England). - : SAGE Publications. - 1741-2684 .- 1471-3012. ; 18:4, s. 1568-1595
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Tidskriftsartikel (refereegranskat)abstract
- Assistive technologies became pervasive and virtually present in all our life domains. They can be either an enabler or an obstacle leading to social exclusion. The Fondation Médéric Alzheimer gathered international experts of dementia care, with backgrounds in biomedical, human and social sciences, to analyze how assistive technologies can address the capabilities of people with dementia, on the basis of their needs. Discussion covered the unmet needs of people with dementia, the domains of daily life activities where assistive technologies can provide help to people with dementia, the enabling and empowering impact of technology to improve their safety and wellbeing, barriers and limits of use, technology assessment, ethical and legal issues. The capability approach (possible freedom) appears particularly relevant in person-centered dementia care and technology development. The focus is not on the solution, rather on what the person can do with it: seeing dementia as disability, with technology as an enabler to promote capabilities of the person, provides a useful framework for both research and practice. This article summarizes how these concepts took momentum in professional practice and public policies in the past 15 years (2000–2015), discusses current issues in the design, development and economic model of assistive technologies for people with dementia, and covers how these technologies are being used and assessed.
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| 19. |
- Arbaugh, B, et al.
(författare)
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Subject matter effects and the community of inquiry framework : An exploratory study
- 2009
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Ingår i: The Internet and higher education. - : Elsevier BV. - 1096-7516 .- 1873-5525. ; 13:1-2, s. 37-44
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Tidskriftsartikel (refereegranskat)abstract
- This paper integrates the emerging literatures of empirical research oil the Community of Inquiry (Col) framework and disciplinary effects in online teaching and learning by examining the disciplinary differences in perceptions of social, teaching, and cognitive presence of over 1500 students in seven disciplines at two U S institutions Our results found significant disciplinary differences, particularly regarding cognitive presence, in soft, applied disciplines relative to other disciplines. These initial results suggest the possibility that the Col framework play be more applicable to applied disciplines than pure disciplines Our findings suggest interesting opportunities for future researchers to consider how the individual elements of the Col framework may influence and be influenced by academic disciplines and how the framework play need to be refined or modified to explain effective course conduct in pure disciplines.
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| 20. |
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| 21. |
- Axen, Iben, et al.
(författare)
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Misinformation, chiropractic, and the COVID-19 pandemic
- 2020
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Ingår i: Chiropractic and Manual Therapies. - : BioMed Central (BMC). - 2045-709X. ; 28:1
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Background: In March 2020, the World Health Organization elevated the coronavirus disease (COVID-19) epidemic to a pandemic and called for urgent and aggressive action worldwide. Public health experts have communicated clear and emphatic strategies to prevent the spread of COVID-19. Hygiene rules and social distancing practices have been implemented by entire populations, including 'stay-at-home' orders in many countries. The long-term health and economic consequences of the COVID-19 pandemic are not yet known.Main text: During this time of crisis, some chiropractors made claims on social media that chiropractic treatment can prevent or impact COVID-19. The rationale for these claims is that spinal manipulation can impact the nervous system and thus improve immunity. These beliefs often stem from nineteenth-century chiropractic concepts. We are aware of no clinically relevant scientific evidence to support such statements. We explored the internet and social media to collect examples of misinformation from Europe, North America, Australia and New Zealand regarding the impact of chiropractic treatment on immune function. We discuss the potential harm resulting from these claims and explore the role of chiropractors, teaching institutions, accrediting agencies, and legislative bodies.Conclusions: Members of the chiropractic profession share a collective responsibility to act in the best interests of patients and public health. We hope that all chiropractic stakeholders will view the COVID-19 pandemic as a call to action to eliminate the unethical and potentially dangerous claims made by chiropractors who practise outside the boundaries of scientific evidence.
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| 22. |
- Campos-Xavier, Ana Belinda, et al.
(författare)
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Mutations in the heparan-sulfate proteoglycan glypican 6 (GPC6) impair endochondral ossification and cause recessive omodysplasia
- 2009
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Ingår i: American Journal of Human Genetics. - : Elsevier BV. - 0002-9297 .- 1537-6605. ; 84:6, s. 760-70
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Tidskriftsartikel (refereegranskat)abstract
- Glypicans are a family of glycosylphosphatidylinositol (GPI)-anchored, membrane-bound heparan sulfate (HS) proteoglycans. Their biological roles are only partly understood, although it is assumed that they modulate the activity of HS-binding growth factors. The involvement of glypicans in developmental morphogenesis and growth regulation has been highlighted by Drosophila mutants and by a human overgrowth syndrome with multiple malformations caused by glypican 3 mutations (Simpson-Golabi-Behmel syndrome). We now report that autosomal-recessive omodysplasia, a genetic condition characterized by short-limbed short stature, craniofacial dysmorphism, and variable developmental delay, maps to chromosome 13 (13q31.1-q32.2) and is caused by point mutations or by larger genomic rearrangements in glypican 6 (GPC6). All mutations cause truncation of the GPC6 protein and abolish both the HS-binding site and the GPI-bearing membrane-associated domain, and thus loss of function is predicted. Expression studies in microdissected mouse growth plate revealed expression of Gpc6 in proliferative chondrocytes. Thus, GPC6 seems to have a previously unsuspected role in endochondral ossification and skeletal growth, and its functional abrogation results in a short-limb phenotype.
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| 23. |
- Cleveland-Innes, Martha, et al.
(författare)
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Assessing emotional presence in Communities of Inquiry : From the instructors point of view
- 2019
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Konferensbidrag (refereegranskat)abstract
- For Garrison, a Community of Inquiry is a group of individuals who collaboratively engage in purposeful critical discourse and reflection to construct meaning and confirm mutual understanding. In this study, we add Lehman’s argument that emotions are necessary to create a presence in an online learning environment and suggest that emotional presence supports reflection and knowledge construction. Using the Community of Inquiry theoretical framework and measurement tools as a base, this study measures to the extent to which instructors identify the existence of emotional presence among their students. This identification of emotion may allow instructors to respond according, if and when needed, to deflect or direct emotion in reference to building presence and, ultimately, a community of inquiry.In 2016 pilot testing of a revised CoI measurement tool, written from the instructor ‘s point of view, was tested in faculty development workshops. Following this pilot test, the instrument was used with a total of 287 higher education faculty from Portland, Oregon USA, in Beijing, China, and Sundsval, Sweden. Results indicate a correlation between years of teaching and acknowledgement of emotion but not a separate place for emotional presence in the community of inquiry framework. This is in contrast to studies of online learners where emotional presence emerges as a unique element in a community of inquiry. This paper presentation will review these findings in contrast to other similar studies and facilitate discussion of possible differences in perceptions of emotional presence between instructors and learners.
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| 26. |
- Horsley, Alex R, et al.
(författare)
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Effects of cystic fibrosis lung disease on gas mixing indices derived from alveolar slope analysis.
- 2008
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Ingår i: Respiratory physiology & neurobiology. - : Elsevier BV. - 1569-9048. ; 162:3, s. 197-203
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Tidskriftsartikel (refereegranskat)abstract
- S(cond) and S(acin) are derived from analysis of concentration-normalized phase III slopes (Sn(III)) of a multiple breath inert gas washout. Studies in healthy and COPD subjects suggest these reflect ventilation heterogeneity in conducting and acinar airway zones respectively, but similar studies in cystic fibrosis (CF) are lacking. S(cond), S(acin) and lung clearance index (LCI, a measure of overall gas mixing efficiency) were measured in 22 adults and 18 children with CF and 17 adult and 29 child controls. Plethysmography and gas transfer measurements were performed in adults, and spirometry in all subjects. S(cond) was elevated in almost all CF patients, including children with mild disease and normal LCI. However, S(cond) did not correlate with other measurements and appeared to reach a maximum; further increase in ventilation heterogeneity being restricted to S(acin). The nature and/or severity of CF lung disease may invalidate assumptions underlying the ability to separate phase III slope analysis of ventilation heterogeneity into proximal and peripheral components, and LCI may be a better indicator of gas mixing in this population.
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| 27. |
- Kiorboe, T., et al.
(författare)
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Intensive aggregate formation with low vertical flux during an upwelling-induced diatom bloom
- 1998
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Ingår i: Limnology and Oceanography. - 0024-3590. ; 43:1, s. 104-116
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Tidskriftsartikel (refereegranskat)abstract
- The surfaces of most pelagic diatoms are sticky at times and may therefore form rapidly settling aggregates by physical coagulation. Stickiness and aggregate formation may be particularly adaptive in upwelling systems by allowing the retention of diatom populations in the vicinity of the upwelling center. We therefore hypothesized that upwelling diatom blooms are terminated by aggregate formation and rapid sedimentation. We monitored the development of a maturing diatom (mainly Chaetoceros spp.) bloom in the Benguela upwelling current during 7 d in February. Chlorophyll concentrations remained consistently high during the observation period (similar to 500 mg Chi m(-2)) and phytoplankton grew at an average specific rate of 0.25 d(-1). The diatoms were extraordinarily sticky, with stickiness coefficients of up to 0.40, which is the highest ever recorded for field populations. Combined with estimates of turbulent shear in the ocean such stickiness coefficients predict very high specific coagulation rates (0.3 d(-1)). In situ video observation demonstrated the occurrence of abundant diatom aggregates with surface water concentrations between 1,000 and 3,000 ppm. Despite the very high concentration of aggregates, vertical fluxes of phytoplankton were very low, with fractional losses <0.005 d(-1), and the aggregates thus seemed to be near neutrally buoyant. Losses due to copepod grazing were also low (similar to 0.025 d(-1)). Most of the aggregates were colonized by the heterotrophic dinoflagellate Noctiluca scintillans that feed upon diatoms in the aggregates. The system appeared to be in near steady state; specific diatom growth rate, coagulation rate, and loss rate due to N, scintillans feeding were all of the same magnitude (0.25-0.3 d(-1)) and the latter two varied in concert. Our observations provide only partial support for the population retention hypothesis because aggregate buoyancy and N, scintillans grazing efficiently reduced the vertical flux of aggregates in this system.
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| 28. |
- Klein, Richard A., et al.
(författare)
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Many Labs 2 : Investigating variation in replicability across samples and settings
- 2018
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Ingår i: Advances in Methods and Practices in Psychological Science. - : SAGE Publications. - 2515-2459 .- 2515-2467. ; 1:4, s. 443-490
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Tidskriftsartikel (refereegranskat)abstract
- We conducted preregistered replications of 28 classic and contemporary published findings, with protocols that were peer reviewed in advance, to examine variation in effect magnitudes across samples and settings. Each protocol was administered to approximately half of 125 samples that comprised 15,305 participants from 36 countries and territories. Using the conventional criterion of statistical significance (p < .05), we found that 15 (54%) of the replications provided evidence of a statistically significant effect in the same direction as the original finding. With a strict significance criterion (p < .0001), 14 (50%) of the replications still provided such evidence, a reflection of the extremely high-powered design. Seven (25%) of the replications yielded effect sizes larger than the original ones, and 21 (75%) yielded effect sizes smaller than the original ones. The median comparable Cohen’s ds were 0.60 for the original findings and 0.15 for the replications. The effect sizes were small (< 0.20) in 16 of the replications (57%), and 9 effects (32%) were in the direction opposite the direction of the original effect. Across settings, the Q statistic indicated significant heterogeneity in 11 (39%) of the replication effects, and most of those were among the findings with the largest overall effect sizes; only 1 effect that was near zero in the aggregate showed significant heterogeneity according to this measure. Only 1 effect had a tau value greater than .20, an indication of moderate heterogeneity. Eight others had tau values near or slightly above .10, an indication of slight heterogeneity. Moderation tests indicated that very little heterogeneity was attributable to the order in which the tasks were performed or whether the tasks were administered in lab versus online. Exploratory comparisons revealed little heterogeneity between Western, educated, industrialized, rich, and democratic (WEIRD) cultures and less WEIRD cultures (i.e., cultures with relatively high and low WEIRDness scores, respectively). Cumulatively, variability in the observed effect sizes was attributable more to the effect being studied than to the sample or setting in which it was studied.
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