Academic literature on the topic '18st century'

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Journal articles on the topic "18st century"

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Leray, Matthieu, and Nancy Knowlton. "Censusing marine eukaryotic diversity in the twenty-first century." Philosophical Transactions of the Royal Society B: Biological Sciences 371, no. 1702 (September 5, 2016): 20150331. http://dx.doi.org/10.1098/rstb.2015.0331.

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The ocean constitutes one of the vastest and richest biomes on our planet. Most recent estimations, all based on indirect approaches, suggest that there are millions of marine eukaryotic species. Moreover, a large majority of these are small (less than 1 mm), cryptic and still unknown to science. However, this knowledge gap, caused by the lack of diagnostic morphological features in small organisms and the limited sampling of the global ocean, is currently being filled, thanks to new DNA-based approaches. The molecular technique of PCR amplification of homologous gene regions combined with high-throughput sequencing, routinely used to census unculturable prokaryotes, is now also being used to characterize whole communities of marine eukaryotes. Here, we review how this methodological advancement has helped to better quantify the magnitude and patterns of marine eukaryotic diversity, with an emphasis on taxonomic groups previously largely overlooked. We then discuss obstacles remaining to achieve a global understanding of marine eukaryotic diversity. In particular, we argue that 18S variable regions do not provide sufficient taxonomic resolution to census marine life, and suggest combining broad eukaryotic surveys targeting the 18S rRNA region with more taxon-focused analyses of hypervariable regions to improve our understanding of the diversity of species, the functional units of marine ecosystems. This article is part of the themed issue ‘From DNA barcodes to biomes’.
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KOLBASOVA, G., and T. NERETINA. "A new species of Pelagobia (Lopadorrhynchidae, Annelida), with some notes on literature records of Pelagobia longicirrata Greeff, 1879." Zootaxa 5023, no. 1 (August 17, 2021): 77–92. http://dx.doi.org/10.11646/zootaxa.5023.1.4.

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Since the second half of the XX century, almost all Pelagobia samples from the Arctic, Antarctic, Atlantic and Pacific oceans had been identified as cosmopolitan P. longicirrata. The indistinct nuchal organs in P. longicirrata samples from the South China Sea (Spratly Islands and Taiwan) were considered a morphological feature of the Pacific population. Our morphological and genetic investigation of Pelagobia specimens from the Nhatrang Bay, Vietnam reveals a new species in this region. Pelagobia rubromaculata sp. nov. differs from P. longicirrata by its triangle head, with nuchal organs closely adjacent to the lateral sides of prostomium, by short tentacular cirri reaching only the posterior edge of the third segment, and by a specific colouration pattern with red spots. Using nuclear 18S and 28S rDNA markers reveals that P. rubromaculata sp. nov. forms a well-supported clade, confirming the validity of the new species. Phylogenetic analysis of all available P. longicirrata sequences using both single 18S and concatenated 18S and 28S genes shows at least three distinct clades: Central Atlantic, Arctic and South Atlantic. Antarctic specimens do not form any distinct clade and fall between other clades with low support.
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Gyulai, G., M. Humphreys, R. Lagler, Z. Szabo, Z. Toth, A. Bittsanszky, F. Gyulai, and L. Heszky. "Seed remains of common millet from the 4th (Mongolia) and 15th (Hungary) centuries: AFLP, SSR and mtDNA sequence recoveries." Seed Science Research 16, no. 3 (September 2006): 179–91. http://dx.doi.org/10.1079/ssr2006251.

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Seed remains of common millet (Panicum miliaceumL.) were excavated from sites of ad 4th-century Darhan (Mongolia), and ad 15th-century Budapest (Hungary). Because the 15th-century medieval grains looked so intact, a germination test was carried out under aseptic conditions, which resulted in swelling of the grains but no cell proliferation or germination. Ancient DNA (aDNA) was extracted from the aseptic grains; analysed for amplified fragment length polymorphisms (AFLP), simple sequence repeats (SSR) and mitochondrial DNA (mtDNA); and compared with the modern millet cultivar ‘Topaz’. AFLP analysis revealed that extensive DNA degradation had occurred in the 4th-century ancient millet, resulting in only 2 (1.2%) AFLP fragments (98.8% degradation) amplified byMseCAA–EcoAGT, compared to the 15th-century medieval millet, with 158 (40%) fragments (60% degradation), and modern millet cultivar ‘Topaz’ with 264 fragments (100%).EcoAGT–MseCAA was found to be the most effective selective-primer combination for the analysis of medieval and modern millet. Eight AFLP fragments were sequenced after re-amplification and cloning. Microsatellite (SSR) analysis at the nucleargln4,sh1,rps28 andrps15 loci revealed one SNP (single nucleotide polymorphism) at the 29th position (A→G) ofrps28 locus, compared to modern millet. An mtDNA fragment (MboI), amplified at the 18S–5S ribosomal DNA (rDNA) locus in the medieval millet, showed no molecular changes compared to modern millet. The results underline the significance of aDNA extraction and analysis of excavated seeds for comparative analysis and molecular reconstruction of ancient and extinct plant genotypes.
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Zakiyah, Zakiyah. "KITAB AL-SANĪ AL-MAṬĀLIB: INTERKONEKSI NAHWU DAN TASAWUF." Walisongo: Jurnal Penelitian Sosial Keagamaan 20, no. 2 (December 15, 2012): 371. http://dx.doi.org/10.21580/ws.2012.20.2.204.

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<p class="IIABSBARU">This paper reviews a book entitled al-Sanī al-Maṭālib written by Kiai Nur Iman Mlangi Yogyakarta. This book is written in Arabic containing an interconnection between Arabic grammar and mysticism. This book is very interesting due to the fact that those two knowledges have its own rules. In addition, there is only small number of authors who had written with the same model, to name one of them is Shaikh Abdul Qadir bin Ahmad al-Kuhany with his work entitled Manniyat al-Fāqir al-Munjarid wa Sayrat al-Murīd al-Mutafarrid”. The book al-Sanī al-Maṭālib was predicted written in the late 18s Century or the beginning of 19s century, it is based on the period of Kiai Nur Iman’s life in which around the mid of 18s century. The grammatical rule of Arabic in this book was explained theo­sophically, it is started with the explanation of tauhid (oneness) as the basic learning for Muslim, followed by the meaning of each Arabic rule in mystical aspect.</p><p class="IKa-ABSTRAK">***</p><p class="IIABSBARU">Tulisan ini mereview buku yang berjudul <em>al-Sanī al-Maṭālib</em> yang ditulis oleh Kiai Nur Iman Mlangi Yogyakarta. Buku ini ditulis dalam bahasa Arab yang me­ngandung interkoneksi antara ilmu Nahwu (tata bahasa Arab) dengan mis­tisis­me. Buku ini sangat menarik karena kenyataan bahwa kedua pengetahuan tersebut memiliki aturan sendiri-sendiri. Selain itu, sangat sedikit penulis yang menulis dengan gaya seperti itu. Salah satunya adalah Syaikh Abdul Qadir bin Ahmad al-Kuhany dengan karyanya yang berjudul <em>Manniyat al-Fāqir al-Munjarid wa Sayrat al-Murīd al-Mutafarrid</em>. Buku al-Saniy al-Muthalib diduga telah ditulis pada akhir abad ke-18 atau awal abad ke-19, menurut periode kehidupan Kiai Nur Iman yaitu sekitar pertengahan abad ke-18. Aturan Nahwu dalam buku ini dijelaskan secara teosofi yang dimulai dengan penjelasan mengenai tauhid (keesaan Tuhan) sebagai kajian dasar bagi orang Islam, yang diikuti dengan makna dari masing-masing aturan bahasa Arab dalam aspek mistiknya.</p>
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Escamilla Pérez, Rocío G., Javier Reyes Trujeque, Tezozomoc Pérez López, Víctor Monteón Padilla, and Ruth López Alcántara. "Identification of Microorganisms Associated to the Biodegradation of Historic Masonry Structure in San Francisco de Campeche City, México." MRS Proceedings 1374 (2012): 187–94. http://dx.doi.org/10.1557/opl.2012.1388.

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ABSTRACTTropical climate create ideal conditions for the development of microbial communities associated with biodegradation of historic buildings made with stony materials. This is the case of Fort San Carlos, a historic colonial building representative of military tendencies during the XVII century in San Francisco de Campeche City. In this study the Polymerase Chain Reaction (PCR), was used to identify microorganisms related with the biodegradation of its masonry structure. Specific primers for amplification of 16S and 18S ribosomal RNA genes were used for organisms identification by PCR. Amplification products were sequenced and after that compared with GENBANK nucleotide database using-BLASTn. Results indicated that microbial communities associated to biodegradation of the Fort San Carlos are bacteria from the Phyla Cyanobacteria, Proteobacteria and Actinobacteria.
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Edgecombe, Gregory D., and Gonzalo Giribet. "A century later - a total evidence re-evaluation of the phylogeny of scutigeromorph centipedes (Myriapoda:Chilopoda)." Invertebrate Systematics 20, no. 5 (2006): 503. http://dx.doi.org/10.1071/is05044.

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Scutigeromorpha (‘house centipedes’) play a pivotal role in myriapod systematics in being the sister group to all other chilopods, but their internal phylogeny has not been comprehensively appraised since K. W. Verhoeff’s morphological investigations a century ago. Relationships between the three families of Scutigeromorpha are inferred based on a combined analysis of approximately 5.5 Kb of sequence data from five molecular markers (complete 18S rRNA, a 2.2-Kb fragment of 28S rRNA, 16S rRNA, cytochrome c oxidase subunit I, histone H3) and 33 ingroup morphological characters. Molecular data are available for 19 ingroup terminals representing 14 morphospecies that include the genera Scutigerina, Madagassophora (family Scutigerinidae), Sphendononema (family Pselliodidae), Scutigera, Thereuopoda, Thereuopodina, Thereuonema, Allothereua and Parascutigera (family Scutigeridae). Morphology resolves the southern African–Malagasy Scutigerinidae as sister to all other Scutigeromorpha, whereas rival sister-group relationships between the Neotropical–Afrotropical Pselliodidae and Scutigerinidae + Scutigeridae or Pselliodidae + Scutigerinidae and Scutigeridae are resolved by the molecular and combined analyses. Monophyly of Scutigeridae and Thereuoneminae are stable across a broad range of analytical parameters. Thereuoneminae is composed of two stable clades: an Allothereua + Parascutigera group, and a grouping of Thereuopoda, Thereuonema and Thereuopodina. Molecular and combined analyses resolve the genus Scutigerina and the morphospecies Scutigerina weberi as paraphyletic, in both cases with a Malagasy clade excluding populations from southern Africa.
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Lágler, Richárd, Gábor Gyulai, Zoltán Szabó, Zoltán Tóth, and László Heszky. "Sequence stability at SSR, ISSR and mtDNA loci of common millet (Panicum miliaceum) from the middle ages." Acta Agraria Debreceniensis, no. 27 (November 15, 2007): 10–19. http://dx.doi.org/10.34101/actaagrar/27/3093.

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Seed remains of medieval millet, recovered from a 15th century layer (King’s Palace, Budapest, Hungary), showed reddish yellow grain color after rehydrating on tissue culture medium that was close to grain color of modern cultivar Omszkoje. aDNA of medieval c. millet was extracted successfully, analyzed and compared to modern common millets by ISSR, SSR, CAPS and mtDNA. Analyses of fragments and sequences revealedpolymorphism at seven ISSR loci (22 alleles) and at the 5S-18S rDNA locus of mtDNA. CAPS analysis of the 5S-18S rDNA fragment revealed no SNPs in the restriction sites of six endonucleases TaqI, BsuRI, HinfI, MboI, AluI and RsaI. Sequence alignments of the restriction fragments RsaI also revealedconsensus sequence in the medieval sample compared to a modern variety. Morphological characterization of twenty common millet (Panicum miliaceum L., 2n=4×=36) cultivars and landraces revealed four distinct clusters which were apparently consistent with the grain colors of black, black and brown, red, yellow, and white. In the comparative AFLP, SSR and mtDNA analysis modern millet cv. ‘Topáz’ was used. AFLP analysis revealed that extensive DNA degradation had occurred in the 4th CENT. ancient millet resulting in only 2 (1.2%) AFLP fragments (98.8% degradation),compared to the 15th CENT. medieval millet with 158 (40%) fragments (60% degradation) and modern millet cv. ‘Topáz’ with 264 fragments (100%). Eight AFLP fragments were sequenced after reamplification and cloning. Microsatellite (SSR) analysis at the nuclear gln4, sh1, rps28 and rps15 loci of the medieval DNA revealed one SNP (single nucleotide polymorphism) at the 29th position (A to G) of rps28 locus compared to modern millet.Mitochondrial (mtDNA) fragment (MboI) amplified at the 5S-18S-rDNA locus in the medieval millet showed no molecular changes compared to modern millet. The results underline the significance of survived aDNA extraction and analysis of excavated seeds for comparative analysis and molecular reconstruction of ancient and extinct plant genotypes. An attempted phenotype reconstruction indicated that medieval common millet showed the closest morphological similarity to modern millet cultivar Omszkoje.
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Oliveira, Vanessa C. S., Marie Altmanová, Patrik F. Viana, Tariq Ezaz, Luiz A. C. Bertollo, Petr Ráb, Thomas Liehr, et al. "Revisiting the Karyotypes of Alligators and Caimans (Crocodylia, Alligatoridae) after a Half-Century Delay: Bridging the Gap in the Chromosomal Evolution of Reptiles." Cells 10, no. 6 (June 5, 2021): 1397. http://dx.doi.org/10.3390/cells10061397.

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Although crocodilians have attracted enormous attention in other research fields, from the cytogenetic point of view, this group remains understudied. Here, we analyzed the karyotypes of eight species formally described from the Alligatoridae family using differential staining, fluorescence in situ hybridization with rDNA and repetitive motifs as a probe, whole chromosome painting (WCP), and comparative genome hybridization. All Caimaninae species have a diploid chromosome number (2n) 42 and karyotypes dominated by acrocentric chromosomes, in contrast to both species of Alligatorinae, which have 2n = 32 and karyotypes that are predominantly metacentric, suggesting fusion/fission rearrangements. Our WCP results supported this scenario by revealing the homeology of the largest metacentric pair present in both Alligator spp. with two smaller pairs of acrocentrics in Caimaninae species. The clusters of 18S rDNA were found on one chromosome pair in all species, except for Paleosuchus spp., which possessed three chromosome pairs bearing these sites. Similarly, comparative genomic hybridization demonstrated an advanced stage of sequence divergence among the caiman genomes, with Paleosuchus standing out as the most divergent. Thus, although Alligatoridae exhibited rather low species diversity and some level of karyotype stasis, their genomic content indicates that they are not as conserved as previously thought. These new data deepen the discussion of cytotaxonomy in this family.
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Manuel, M. "Phylogeny and evolution of calcareous sponges." Canadian Journal of Zoology 84, no. 2 (February 1, 2006): 225–41. http://dx.doi.org/10.1139/z06-005.

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The most recent advances concerning the phylogeny and evolution of calcareous sponges (Calcarea or Calcispongia) are reviewed here, in the light of the history of taxonomy of the group and conceptions about its evolution, starting from Haeckel's works at the end of the 19th century. Calcisponge phylogeny has recently started to be addressed using modern tools of phylogenetic reconstruction: cladistic analysis of morphological characters and molecular phylogeny (so far using 18S and 28S rDNA sequences). The monophyly of calcareous sponges is strongly supported in these works, as is their subdivision into two clades, Calcinea (whose proposed synapomorphy is the basal position of nuclei in choanocytes, with no relation to the flagella) and Calcaronea (whose possible synapomorphy is the formation of the amphiblastula larva through the original process of eversion of the stomoblastula). While the molecular phylogeny of Calcinea is still in its infancy because of insufficient taxonomic sampling, several lines are emerging for the phylogeny of Calcaronea, and these are in strong disagreement with the classification issued from the "traditional" morphological approach. Phylogenetic hypotheses also permit the reconstruction of morphological character evolution, which appears complex and subject to a high level of homoplasy.
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Galindo, Luis Javier, Guifré Torruella, David Moreira, Yana Eglit, Alastair G. B. Simpson, Eckhard Völcker, Steffen Clauß, and Purificación López-García. "Combined cultivation and single-cell approaches to the phylogenomics of nucleariid amoebae, close relatives of fungi." Philosophical Transactions of the Royal Society B: Biological Sciences 374, no. 1786 (October 7, 2019): 20190094. http://dx.doi.org/10.1098/rstb.2019.0094.

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Nucleariid amoebae (Opisthokonta) have been known since the nineteenth century but their diversity and evolutionary history remain poorly understood. To overcome this limitation, we have obtained genomic and transcriptomic data from three Nuclearia , two Pompholyxophrys and one Lithocolla species using traditional culturing and single-cell genome (SCG) and single-cell transcriptome amplification methods. The phylogeny of the complete 18S rRNA sequences of Pompholyxophrys and Lithocolla confirmed their suggested evolutionary relatedness to nucleariid amoebae, although with moderate support for internal splits. SCG amplification techniques also led to the identification of probable bacterial endosymbionts belonging to Chlamydiales and Rickettsiales in Pompholyxophrys . To improve the phylogenetic framework of nucleariids, we carried out phylogenomic analyses based on two datasets of, respectively, 264 conserved proteins and 74 single-copy protein domains. We obtained full support for the monophyly of the nucleariid amoebae, which comprise two major clades: (i) Parvularia–Fonticula and (ii) Nuclearia with the scaled genera Pompholyxophrys and Lithocolla . Based on these findings, the evolution of some traits of the earliest-diverging lineage of Holomycota can be inferred. Our results suggest that the last common ancestor of nucleariids was a freshwater, bacterivorous, non-flagellated filose and mucilaginous amoeba. From the ancestor, two groups evolved to reach smaller ( Parvularia–Fonticula ) and larger ( Nuclearia and related scaled genera) cell sizes, leading to different ecological specialization. The Lithocolla + Pompholyxophrys clade developed exogenous or endogenous cell coverings from a Nuclearia -like ancestor. This article is part of a discussion meeting issue ‘Single cell ecology’.
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Dissertations / Theses on the topic "18st century"

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JENSEN, Mikkel Munthe. "From learned cosmopolitanism to scientific inter-nationalism : the patriotic transformation of Nordic academia and academic culture during the long eighteenth century." Doctoral thesis, 2018. http://hdl.handle.net/1814/52924.

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Defence date: 21 March 2018
Examining Board: Prof. Stéphane Van Damme, European University Institute; Prof. Ann Thomson, European University Institute; Prof. Howard Hotson, Oxford University; Prof. Marian Füssel, Georg-August-Universität Göttingen
This dissertation is a study of Nordic academia and its relation to the growing patriotic State. The dissertation examines how, why and to what extent Nordic academia transformed with to the rise of patriotism during the long Eighteenth Century as well as what consequences this transformation had for academic citizens, their institutional and academic practices and self-conceptions. Based on a composite methodology of quantitative and qualitative approaches, the dissertation examines this transformation by studying all 592 professors at the six Nordic universities through a transnational and comparative perspective. The dissertation argues, that the State’s increased interest in and need for science and education during the eighteenth century initiated a consolidation between the State and the University, and at the same time, the rise of patriotism and its stronger focus on the natural fatherland began a nationalisation process at the universities. Through an institutional and socio-cultural examination of the Nordic universities and their professors, this dissertation, firstly, demonstrates that Nordic academia was institutionally and culturally rooted in a centuries-old pan-European academic community and also shared its learned cosmopolitan notions. Secondly, the dissertation argues that it was these notions and practices of a cosmopolitan academia that were disrupted and transformed with the rise of patriotism and State power. It argues, that the State and the University consolidated in a shared patriotic purpose of prioritising the King, Country and fellow citizens above all other considerations. This new purpose changed both the universities’ institutional and academic practices overall, as national requirements and precedences were introduced, as well as the professors’ perceived scholarly and societal role, as they were no longer seen simply as scholars of the learned world but rather as State servants of the fatherland. Consequently, this new agenda and practices disrupted the cosmopolitan nature of the old academic community.
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Books on the topic "18st century"

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Twain, Mark. The Adventures of Tom Sawyer (EasyRead Super Large 18pt Edition). ReadHowYouWant, 2008.

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Conference papers on the topic "18st century"

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Wilson, Jani. "Rōpū Whānau: A whakawhiti kōrero research methodology." In LINK 2022. Tuwhera Open Access, 2022. http://dx.doi.org/10.24135/link2022.v3i1.181.

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Kapahaka is not simply the song and dance of Aotearoa’s Indigenous people. Deeply steeped in mātauranga Māori, kapahaka is a way of simultaneously exemplifying Māori histories, the present, and the future; meanwhile it is a community-focused cultural practice, methodology, and pedagogy. Contemporary kapahaka – both competitive and for entertainment – fosters, develops, validates, and celebrates the Māori world, the language, and our ‘ways’: arguably the fundamental building blocks of Māori ‘popular culture’. The research project Kia Rite! Kapahaka for Screens, from which this presentation is a tiny proportion, will focus on the influence and impact of screen production on the art’s ebbs and flows, and the conflicts between maintaining ‘traditions’ and exploring innovation in and towards the future. Over the last century, the kapahaka art-form has evolved exponentially, and as the wider project will explore, in large part as a response to the advancement of screen technologies. An important strand in Kia Rite! will investigate the kapahaka audience. It employs a refined iteration of Rōpū Whānau, a focus group methodology where closely linked relations will be asked to respond to archival through to contemporary kapahaka footage as a generational screen audience study. Exploring responses to screened kapahaka in this way revisits a whakawhiti kōrero-based audience study method designed to reflect and embody the fundamental whakataukī ‘he aha te kai o ngā rangatira? He kōrero’ (what is the food of chiefs? It is talk.) Rōpū Whānau was developed to move beyond the ‘safety in numbers’ focus group methodology to more of a ‘safety within the whānau’ format. By inviting participants from the same family, a duty to protect the under 18s and inherently control researcher behaviours provides an extra layer of a kind of ‘Māori ethics’. This critical presentation brings forward the fundamental elements of Rōpū Whānau and unpacks how it has been used in various research projects in the past. This is to plot the way forward for Indigenous community-led research methodologies, and encourages the consideration of Indigenous research approaches.
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