| 1. |
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| 2. |
- Emile-Geay, J., et al.
(author)
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Data Descriptor: A global multiproxy database for temperature reconstructions of the Common Era
- 2017
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In: Scientific Data. - : Springer Science and Business Media LLC. - 2052-4463. ; 4
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Journal article (peer-reviewed)abstract
- Reproducible climate reconstructions of the Common Era (1 CE to present) are key to placing industrial-era warming into the context of natural climatic variability. Here we present a community-sourced database of temperature-sensitive proxy records from the PAGES2k initiative. The database gathers 692 records from 648 locations, including all continental regions and major ocean basins. The records are from trees, ice, sediment, corals, speleothems, documentary evidence, and other archives. They range in length from 50 to 2000 years, with a median of 547 years, while temporal resolution ranges from biweekly to centennial. Nearly half of the proxy time series are significantly correlated with HadCRUT4.2 surface temperature over the period 1850-2014. Global temperature composites show a remarkable degree of coherence between high-and low-resolution archives, with broadly similar patterns across archive types, terrestrial versus marine locations, and screening criteria. The database is suited to investigations of global and regional temperature variability over the Common Era, and is shared in the Linked Paleo Data (LiPD) format, including serializations in Matlab, R and Python. Since the pioneering work of D'Arrigo and Jacoby1-3, as well as Mann et al. 4,5, temperature reconstructions of the Common Era have become a key component of climate assessments6-9. Such reconstructions depend strongly on the composition of the underlying network of climate proxies10, and it is therefore critical for the climate community to have access to a community-vetted, quality-controlled database of temperature-sensitive records stored in a self-describing format. The Past Global Changes (PAGES) 2k consortium, a self-organized, international group of experts, recently assembled such a database, and used it to reconstruct surface temperature over continental-scale regions11 (hereafter, ` PAGES2k-2013'). This data descriptor presents version 2.0.0 of the PAGES2k proxy temperature database (Data Citation 1). It augments the PAGES2k-2013 collection of terrestrial records with marine records assembled by the Ocean2k working group at centennial12 and annual13 time scales. In addition to these previously published data compilations, this version includes substantially more records, extensive new metadata, and validation. Furthermore, the selection criteria for records included in this version are applied more uniformly and transparently across regions, resulting in a more cohesive data product. This data descriptor describes the contents of the database, the criteria for inclusion, and quantifies the relation of each record with instrumental temperature. In addition, the paleotemperature time series are summarized as composites to highlight the most salient decadal-to centennial-scale behaviour of the dataset and check mutual consistency between paleoclimate archives. We provide extensive Matlab code to probe the database-processing, filtering and aggregating it in various ways to investigate temperature variability over the Common Era. The unique approach to data stewardship and code-sharing employed here is designed to enable an unprecedented scale of investigation of the temperature history of the Common Era, by the scientific community and citizen-scientists alike.
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| 3. |
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| 4. |
- Buntgen, U., et al.
(author)
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Tree rings reveal globally coherent signature of cosmogenic radiocarbon events in 774 and 993 CE
- 2018
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In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 9
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Journal article (peer-reviewed)abstract
- Though tree-ring chronologies are annually resolved, their dating has never been independently validated at the global scale. Moreover, it is unknown if atmospheric radiocarbon enrichment events of cosmogenic origin leave spatiotemporally consistent fingerprints. Here we measure the 14C content in 484 individual tree rings formed in the periods 770–780 and 990–1000 CE. Distinct 14C excursions starting in the boreal summer of 774 and the boreal spring of 993 ensure the precise dating of 44 tree-ring records from five continents. We also identify a meridional decline of 11-year mean atmospheric radiocarbon concentrations across both hemispheres. Corroborated by historical eye-witness accounts of red auroras, our results suggest a global exposure to strong solar proton radiation. To improve understanding of the return frequency and intensity of past cosmic events, which is particularly important for assessing the potential threat of space weather on our society, further annually resolved 14C measurements are needed.
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| 5. |
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| 6. |
- Jackson, Victoria E, et al.
(author)
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Meta-analysis of exome array data identifies six novel genetic loci for lung function.
- 2018
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In: Wellcome open research. - : F1000 Research Ltd. - 2398-502X. ; 3
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Journal article (peer-reviewed)abstract
- Background: Over 90 regions of the genome have been associated with lung function to date, many of which have also been implicated in chronic obstructive pulmonary disease. Methods: We carried out meta-analyses of exome array data and three lung function measures: forced expiratory volume in one second (FEV 1), forced vital capacity (FVC) and the ratio of FEV 1 to FVC (FEV 1/FVC). These analyses by the SpiroMeta and CHARGE consortia included 60,749 individuals of European ancestry from 23 studies, and 7,721 individuals of African Ancestry from 5 studies in the discovery stage, with follow-up in up to 111,556 independent individuals. Results: We identified significant (P<2·8x10 -7) associations with six SNPs: a nonsynonymous variant in RPAP1, which is predicted to be damaging, three intronic SNPs ( SEC24C, CASC17 and UQCC1) and two intergenic SNPs near to LY86 and FGF10. Expression quantitative trait loci analyses found evidence for regulation of gene expression at three signals and implicated several genes, including TYRO3 and PLAU. Conclusions: Further interrogation of these loci could provide greater understanding of the determinants of lung function and pulmonary disease.
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| 7. |
- Zammit, A. R., et al.
(author)
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A Coordinated Multi-study Analysis of the Longitudinal Association Between Handgrip Strength and Cognitive Function in Older Adults
- 2021
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In: The journals of gerontology. Series B, Psychological sciences and social sciences. - : Oxford University Press (OUP). - 1758-5368 .- 1079-5014. ; 76:2, s. 229-241
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Journal article (peer-reviewed)abstract
- OBJECTIVE: Handgrip strength, an indicator of overall muscle strength, has been found to be associated with slower rate of cognitive decline and decreased risk for cognitive impairment and dementia. However, evaluating the replicability of associations between aging-related changes in physical and cognitive functioning is challenging due to differences in study designs and analytical models. A multiple-study coordinated analysis approach was used to generate new longitudinal results based on comparable construct-level measurements and identical statistical models and to facilitate replication and research synthesis. METHODS: We performed coordinated analysis on 9 cohort studies affiliated with the Integrative Analysis of Longitudinal Studies of Aging and Dementia (IALSA) research network. Bivariate linear mixed models were used to examine associations among individual differences in baseline level, rate of change, and occasion-specific variation across grip strength and indicators of cognitive function, including mental status, processing speed, attention and working memory, perceptual reasoning, verbal ability, and learning and memory. Results were summarized using meta-analysis. RESULTS: After adjustment for covariates, we found an overall moderate association between change in grip strength and change in each cognitive domain for both males and females: Average correlation coefficient was 0.55 (95% CI = 0.44-0.56). We also found a high level of heterogeneity in this association across studies. DISCUSSION: Meta-analytic results from nine longitudinal studies showed consistently positive associations between linear rates of change in grip strength and changes in cognitive functioning. Future work will benefit from the examination of individual patterns of change to understand the heterogeneity in rates of aging and health-related changes across physical and cognitive biomarkers. Published by Oxford University Press on behalf of The Gerontological Society of America 2019.
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| 8. |
- Fargas, G., et al.
(author)
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Influence of cyclic thermal treatments on the oxidation behavior of Ti-6Al-2Sn-4Zr-2Mo alloy
- 2018
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In: Materials Characterization. - : Elsevier BV. - 1044-5803 .- 1873-4189. ; 145, s. 218-224
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Journal article (peer-reviewed)abstract
- Ti-6Al-2Sn-4Zr-2Mo is one of the most common titanium alloys for aerospace industry. This alloy experiences oxidation phenomenon at elevated temperatures. In the present study, cyclic thermal treatments were performed in air at 500, 593 and 700 °C, up to 500 cycles, in order to determine the oxidation kinetics and to analyze the oxide scale and alpha-case formation. Moreover, results were compared to those achieved under isothermal conditions to elucidate differences between both thermal conditions. In this sense, metallographic techniques and X-ray diffraction, together with a detailed advanced characterization of the microstructure by Field Emission Scanning Electron Microscopy and Focus Ions Beam, were used to analyze surface oxidation evolution. Results pointed out that cyclic treatments induced a strong increase of the weight gain compared to isothermal treatments. The analysis of the oxide scale revealed the formation of not only rutile, as isothermal treatments, but also anatase. Thickness of the oxide scale was higher for cyclic conditions, while alpha case did not exceed values reached by isothermal treatments and even became lower at 500 °C.
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| 9. |
- Granqvist, Pehr, et al.
(author)
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Disorganized attachment in infancy : a review of the phenomenon and its implications for clinicians and policy-makers
- 2017
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In: Attachment & Human Development. - : Informa UK Limited. - 1461-6734 .- 1469-2988. ; 19:6, s. 534-558
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Research review (peer-reviewed)abstract
- Disorganized/Disoriented (D) attachment has seen widespread interest from policy makers, practitioners, and clinicians in recent years. However, some of this interest seems to have been based on some false assumptions that (1) attachment measures can be used as definitive assessments of the individual in forensic/child protection settings and that disorganized attachment (2) reliably indicates child maltreatment, (3) is a strong predictor of pathology, and (4) represents a fixed or static trait of the child, impervious to development or help. This paper summarizes the evidence showing that these four assumptions are false and misleading. The paper reviews what is known about disorganized infant attachment and clarifies the implications of the classification for clinical and welfare practice with children. In particular, the difference between disorganized attachment and attachment disorder is examined, and a strong case is made for the value of attachment theory for supportive work with families and for the development and evaluation of evidence-based caregiving interventions.
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| 10. |
- Sun, Ge, et al.
(author)
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Interactive influences of ozone and climate on streamflow of forested watersheds
- 2012
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In: Global Change Biology. - : Wiley. - 1365-2486 .- 1354-1013. ; 18:11, s. 3395-3409
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Journal article (peer-reviewed)abstract
- The capacity of forests to mitigate global climate change can be negatively influenced by tropospheric ozone that impairs both photosynthesis and stomatal control of plant transpiration, thus affecting ecosystem productivity and watershed hydrology. We have evaluated individual and interactive effects of ozone and climate on late season streamflow for six forested watersheds (38-970,000 ha) located in the southeastern United States. Models were based on 18-26 year data records for each watershed and involved multivariate analysis of interannual variability of late season streamflow in response to physical and chemical climate during the growing season. In all cases, some combination of ozone variables significantly improved model performance over climate-only models. Effects of ozone and ozone×climate interactions were also consistently negative and were proportional to variations in actual ozone exposures, both spatially across the region and over time. Conservative estimates of the influence of ozone on the variability (R2) of observed flow ranged from 7% in the area of lowest ozone exposure in West Virginia to 23% in the areas of highest exposure in Tennessee. Our results are supported by a controlled field study using free-air concentration enrichment (FACE) methodology which indicated progressive ozone-induced loss of stomatal control over tree transpiration during the summer in mixed aspen-birch stands. Despite the frequent assumption that ozone reduces tree water loss, our findings support increasing evidence that ozone at near ambient concentrations can reduce stomatal control of leaf transpiration, and increase water use. Increases in evapotranspiration and associated streamflow reductions in response to ambient ozone exposures are expected to episodically increase the frequency and severity of drought and affect flow-dependent aquatic biota in forested watersheds. Regional and global models of hydrologic cycles and related ecosystem functions should consider potential interactions of ozone with climate under both current and future warmer and ozone enriched climatic conditions.
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| 11. |
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| 12. |
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| 13. |
- Andersson, Annika, 1966-
(author)
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Second language acquisition in 6- to 8-year-old native Spanish-speaking children : ERP studies of phonological awareness, semantics, and syntax
- 2012
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Doctoral thesis (other academic/artistic)abstract
- Most people in the world and about a fifth of all school-aged Americans speak at least two languages. Nevertheless, little is known about second language (L2) processing in development, even though language proficiency is strongly related to success in almost all domains. Whereas behavioral studies of L2 acquisition in children are abundant, neurocognitive studies of L2 processing typically are limited to adults with several years of exposure, who may use general cognitive mechanisms to compensate for any difficulties in L2 processing. Research on bilingual adults suggests that age of acquisition (AoA) and proficiency have different effects on different aspects of L2 processing. The present study therefore recorded event-related brain potentials (ERPs) in order to index processes of phonological awareness (Rhyming effect: RE), semantics (N400), and syntax (LAN, P600) in bilingual and monolingual children 6-8 years of age. Even though behaviorally, bilingual children with an average AoA of 4 years had lower English proficiency than monolingual children, proficiency predicted similar differences in ERPs across groups: greater proficiency was linked with shorter latencies and higher amplitudes of all ERP components. Latency in these cases represents speed of processing while amplitude of ERP effects in children can be thought of as an indication of detection of the introduced violations. The appearance of the anterior rhyming effect, latency of the posterior rhyming effect, along with the distribution of the anterior ERP effect for phrase structure violations were related to AoA. More specifically, bilingual 6- to 8-year olds of higher English proficiency processed rhyming nonwords slower than 3- to 5-year-old monolingual children, which could have a strong impact on later vocabulary acquisition. Differences across lingualism groups in distribution of the anterior negativity elicited by phrase structure violations could indicate different neural generators for processing of syntax. Noteworthy is that differences in processing as illustrated by these ERP effects were recorded even though in both these cases bilingual children's English proficiency were within the normal range expected of monolingual children of similar age. Early acquisition was thus important for processing of rhyming and for more automatic syntactic processing as revealed by differences in the anterior negativity.
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| 14. |
- Anti, Marta-Lena, et al.
(author)
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Effect of silicon on creep properties of titanium 6Al-2Sn-4Zr-2Mo alloy
- 2020
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In: MATEC Web of Conferences. - : EDP Sciences. - 2261-236X. ; 321
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Journal article (peer-reviewed)abstract
- The alloy Ti-6Al-2Sn-4Zr-2Mo is a titanium alloy for elevated temperatures often used in aerospace applications. Minor additions of silicon have proven to improve the creep resistance of this alloy. In this work, three different amounts of silicon (0.015, 0.07 and 0.162 wt% Si) were added to cast Ti-6242 and creep tests were performed at different temperatures and loads. Creep resistance increased significantly with silicon addition by means of silicide precipitation hindering dislocations movement. Silicon rich nanoparticles in the microstructure were detected and their effect on creep resistance was investigated. The instruments used in this study were light optical microscope (LOM) and scanning electron microscopy (SEM).
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| 15. |
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| 16. |
- Čapek, J., et al.
(author)
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Influence of laser powder bed fusion scanning pattern on residual stress and microstructure of alloy 718
- 2022
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In: Materials & design. - : Elsevier Ltd. - 0264-1275 .- 1873-4197. ; 221
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Journal article (peer-reviewed)abstract
- A comprehensive investigation is undertaken on the effect of laser scanning pattern on the microstructure of cylindrical samples made of Alloy 718 processed by Laser Powder Bed Fusion. It is observed that the common alternate direction scanning of the laser results in a more homogeneous microstructure than the less common concentric line scans where significant microstructural heterogeneities are seen between the edges and the center of the sample. The investigation focuses on the precipitation, crystallographic texture, grain size, grain morphology and residual stresses utilizing synchrotron X-ray diffraction, neutron diffraction and electron microscopy. The heterogeneous microstructure of the sample processed with the concentric laser pattern influences the chemical composition of the matrix, which alters the reference “strain free” interplanar spacing used for evaluating the residual strain. The investigation underlines the significance of the processing parameters on the homogeneity of the microstructure and the effect of the chemical variations on the determination of residual stresses in materials such as Alloy 718, where strong local chemical variations occur because of different types and extent of precipitation. © 2022
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| 17. |
- Čapek, J., et al.
(author)
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The Effect of γ″ and δ Phase Precipitation on the Mechanical Properties of Inconel 718 Manufactured by Selective Laser Melting : An In Situ Neutron Diffraction and Acoustic Emission Study
- 2021
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In: JOM. - : Springer. - 1047-4838 .- 1543-1851. ; 73:1, s. 223-232
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Journal article (peer-reviewed)abstract
- The deformation behavior of additively manufactured Alloy 718 in as-built condition and after annealing was studied in situ under tensile loading along the build direction. Pre-characterization by synchrotron X-ray diffraction and electron microscopy revealed a significant amount of γ″ precipitates in the as-built samples, whereas the γ″ phase was entirely consumed and needle-like δ precipitates appeared in the annealed sample. In situ neutron diffraction (ND) and acoustic emission (AE) enabled indirect observation of the role of the precipitates on the mechanical behavior. ND provided information on the load accommodation in the matrix, while AE detected a strong signal from the interaction of dislocations with the δ-phase precipitates during deformation of the annealed samples. The results imply that in the annealed samples the matrix sheds the load to the precipitates, while in the as-built material the matrix bares a significant load. © 2020, The Author(s).
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| 18. |
- Goel, Sneha, 1993-, et al.
(author)
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Residual stress determination by neutron diffraction in powder bed fusion-built Alloy 718: Influence of process parameters and post-treatment
- 2020
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In: Materials and Design. - : Elsevier BV. - 1873-4197 .- 0264-1275. ; 195
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Journal article (peer-reviewed)abstract
- Alloy 718 is a nickel-based superalloy that is widely used as a structural material for high-temperature applications. One concern that arises when Alloy 718 is manufactured using powder bed fusion (PBF) is that residual stresses appear due to the high thermal gradients. These residual stresses can be detrimental as they can degrade mechanical properties and distort components. In this work, residual stresses in PBF built Alloy 718, using both electron and laser energy sources, were measured by neutron diffraction. The effects of process parameters and thermal post-treatments were studied. The results show that thermal post-treatments effectively reduce the residual stresses present in the material. Moreover, the material built with laser based PBF showed a higher residual stress compared to the material built with electron-beam based PBF. The scanning strategy with the lower amount of residual stresses in case of laser based PBF was the chessboard strategy compared to the bi-directional raster strategy. In addition, the influence of measured and calculated lattice spacing (d0) on the evaluated residual stresses was investigated.
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| 19. |
- Leland, Caroline, et al.
(author)
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Missing Rings, Synchronous Growth, and Ecological Disturbance in a 36-Year Pitch Pine (Pinus rigida) Provenance Study
- 2016
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In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 11:5
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Journal article (peer-reviewed)abstract
- Provenance studies are an increasingly important analog for understanding how trees adapted to particular climatic conditions might respond to climate change. Dendrochronological analysis can illuminate differences among trees from different seed sources in terms of absolute annual growth and sensitivity to external growth factors. We analyzed annual radial growth of 567 36-year-old pitch pine (Pinus rigida Mill.) trees from 27 seed sources to evaluate their performance in a New Jersey Pine Barrens provenance experiment. Unexpectedly, missing rings were prevalent in most trees, and some years-1992, 1999, and 2006-had a particularly high frequency of missing rings across the plantation. Trees from local seed sources (<55 km away from the plantation) had a significantly smaller percentage of missing rings from 1980-2009 (mean: 5.0%), relative to northernmost and southernmost sources (mean: 9.3% and 7.9%, respectively). Some years with a high frequency of missing rings coincide with outbreaks of defoliating insects or dry growing season conditions. The propensity for missing rings synchronized annual variations in growth across all trees and might have complicated the detection of potential differences in interannual variability among seed sources. Average ring width was significantly larger in seed sources from both the southernmost and warmest origins compared to the northernmost and coldest seed sources in most years. Local seed sources had the highest average radial growth. Adaptation to local environmental conditions and disturbances might have influenced the higher growth rate found in local seed sources. These findings underscore the need to understand the integrative impact of multiple environmental drivers, such as disturbance agents and climate change, on tree growth, forest dynamics, and the carbon cycle.
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| 20. |
- Martin-Benito, Dario, et al.
(author)
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DENDROCHRONOLOGICAL DATING OF THE WORLD TRADE CENTER SHIP, LOWER MANHATTAN, NEW YORK CITY
- 2014
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In: Tree-ring research. - : Tree-Ring Society. - 1536-1098 .- 2162-4585. ; 70:2, s. 65-77
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Journal article (peer-reviewed)abstract
- On July 2010, archaeologists monitoring excavation at the World Trade Center site (WTC) in Lower Manhattan found the remains of a portion of a ship's hull. Because the date of construction and origin of the timbers were unknown, samples from different parts of the ship were taken for dendrochronological dating and provenancing. After developing a 280-year long floating chronology from 19 samples of the white oak group (Quercus section Leucobalanus), we used 21 oak chronologies from the eastern United States to evaluate absolute dating and provenance. Our results showed the highest agreement between the WTC ship chronology and two chronologies from Philadelphia (r = 0.36; t = 6.4; p < 0.001; n = 280) and eastern Pennsylvania (r = 0.35; t = 6.3; p < 0.001; n = 280). The last ring dates of the seven best-preserved samples suggest trees for the ship were felled in 1773 CE or soon after. Our analyses suggest that all the oak timbers used to build the ship most likely originated from the same location within the Philadelphia region, which supports the hypothesis independently drawn from idiosyncratic aspects of the vessel's construction, that the ship was the product of a small shipyard. Few late-18th Century ships have been found and there is little historical documentation of how vessels of this period were constructed. Therefore, the ship's construction date of 1773 is important in confirming that the hull encountered at the World Trade Center represents a rare and valuable piece of American shipbuilding history.
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| 21. |
- Neikter, Magnus, 1988-, et al.
(author)
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Texture of electron beam melted Ti-6Al-4V measured with neutron diffraction
- 2020
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Conference paper (peer-reviewed)abstract
- Texture in materials is important as it contributes to anisotropy in the bulk mechanical properties. Ti-6Al-4V built with the additive manufacturing process (AM) electron beam melting (EBM) has been found to have anisotropic mechanical properties. Therefore, this work has been performed to investigate the texture variations of EBM built Ti-6Al-4V with neutron time of flight (TOF). For the work, samples were produced with different build geometries off-set by 90 degrees. A cast sample was additionally analyzed to investigate the bulk texture of conventionally manufactured material. Microstructural characterization was performed and the cast material was found to have a coarse colony α microstructure, whereas the EBM built material had a finer basket weave microstructure. Overall, the texture of the EBM built material was found to be weak having an multiple of random distribution (MRD) index of ~1 for the α phase, whilst the cast material possessed more than twice the amount of preferred orientation i.e. MRD 2.51 for the α phase.
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| 22. |
- Png, C. Y. Maximilian, et al.
(author)
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Effect of EVAR on International Ruptured AAA Mortality-Sex and Geographic Disparities
- 2024
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In: Journal of Clinical Medicine. - : MDPI. - 2077-0383. ; 13:9
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Journal article (peer-reviewed)abstract
- Background: We sought to investigate the differential impact of EVAR (endovascular aneurysm repair) vis-á-vis OSR (open surgical repair) on ruptured AAA (abdominal aortic aneurysm) mortality by sex and geographically.Methods: We performed a retrospective study of administrative data on EVAR from state statistical agencies, vascular registries, and academic publications, as well as ruptured AAA mortality rates from the World Health Organization for 14 14 states across Australasia, East Asia, Europe, and North America.Results: Between 2011-2016, the proportion of treatment of ruptured AAAs by EVAR increased from 26.1 to 43.8 percent among females, and from 25.7 to 41.2 percent among males, and age-adjusted ruptured AAA mortality rates fell from 12.62 to 9.50 per million among females, and from 34.14 to 26.54 per million among males. The association of EVAR with reduced mortality was more than three times larger (2.2 vis-á-vis 0.6 percent of prevalence per 10 percentage point increase in EVAR) among females than males. The association of EVAR with reduced mortality was substantially larger (1.7 vis-á-vis 1.1 percent of prevalence per 10 percentage point increase in EVAR) among East Asian states than European+ states.Conclusions: The increasing adoption of EVAR coincided with a decrease in ruptured AAA mortality. The relationship between EVAR and mortality was more pronounced among females than males, and in East Asian than European+ states. Sex and ethnic heterogeneity should be further investigated.
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