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Silica in palm leaves and palm leaf manuscripts: Silica intra- and inter-species variability in two palm species from South India: a contribution to the Palm Leaf Manuscript Profiling Initiative
No full textInternational audiencePalm leaves of Borassus flabellifer and Corypha umbraculifera have been used for centuries in South and Southeast Asia as writing material. The Palm Leaf Manuscript Profiling Initiative (PLMPI) is a project established by the Cluster of Excellence ‘Understanding Written Artefacts’ (UWA) and the Centre for the Study of Manuscript Cultures (CSMC) at the University of Hamburg, Germany. It aims at studying palm leaf manuscripts from South India using an integrated approach combining techniques from biology and physics to better assess the cultural and historical value of these artefacts. Within this project, we have created of a modern palm leaf collection to serve as a reference for all project participants, and we have carried out the analysis of the silica content of both fresh palm leaves and palm leaf used in manuscripts. Here, we present our preliminary results on the fresh leaves of 176 Borassus and 70 Corypha specimens collected in the plains of Tamil Nadu region in southeastern India. Trees were sampled from 5 bio-geo-regions, which we defined using a principal component analysis of spatially represented climate and soil data, and a k-means classification. Our sampling was restricted to trees of more or less the same age (12-14 years old) and to the 3rd and 14th leaf. We used wet oxidation to extract phytoliths (silica) and, for 10 samples we used two protocols: wet oxidation and dry ashing technique. The data collected allow us to test correlations between silica content of palm leaves (expressed as a percent of the leaf dry weight, %DW) and parameters such as leaf age, tree age, and climate and soil metrics, and combinations of both
Estimating small-grain cereal plant density at early growth stages using leaf tip density dynamics derived from submillimeter-scale RGB imagery
No full textInternational audiencePlant density is an important variable for management and phenotyping of small-grain cereal crops such as wheat and barley. While many image-based estimation methods exist to replace laborious manual counting, most of them rely on empirical relationships that may not generalize well to different sites, growth stages, species and varieties. In this study, we propose a novel small-grain cereal plant density estimation method that uses leaf tip density dynamics derived from submillimeter-scale images acquired at 45° view zenith angle. This method contained two steps. In the first step, a P2PNet deep learning detection model was trained to estimate leaf tip count in a surface of known area to get the leaf tip density. An occlusion correction method was then applied on this density, leading to an estimation error of about 20% at critical growth stages. In the second step, a wheat leaf dynamic model was used to simulate the evolution of leaf tip density over thermal time as functions of several variables, including mean time of plant emergence, phyllochron and plant density. This model was then inverted using a lookup table approach to estimate plant density from leaf tip density dynamics. The results obtained on three test datasets indicated that two observations performed before the appearance of the second and third leaves could be sufficient to attain a relative plant density estimation error of about 10%. We also discussed that this method should be able to work on other datasets without recalibration, and estimate other variables such as phyllochron at early growth stages. The code will be available at: https://github.com/wdwzytc/WheatPlantDensity
Observatoires Milieux-Sociétés et Données Géographiques: Enjeux Méthodologiques et Perspectives
No full textCet article présente un panorama méthodologique des observatoires scientifiques qui considèrent les dimensions milieux et sociétés de phénomènes sur des territoires d'étude et s'intègrent dans les systèmes de décisions territoriales. Il aborde et étudie les écosystèmes, les motivations, les cadres théoriques, les méthodologies et technologies mises en œuvre par ces observatoires orientés vers la modélisation des phénomènes spatio-temporels utiles à la décision. Nous étudions ces observatoires à partir des principes de représentation du temps et de l'espace dans les processus d'acquisition et de partage des données, leur contextualisation au regard de différentes modalités d'utilisation jusqu'aux interactions espace-temps société et leur mise en œuvre dans des applications environnementales et urbaines. Les progrès actuels de la recherche dans la mise en œuvre de ces observatoires et les problématiques encore ouvertes seront discutés
Increased risk of preterm birth in pregnant women exposed to chemotherapy during childhood, adolescence, or young adulthood: A systematic review and a network meta-analysis
No full textInternational audienceObjective: To assess the long-term impact of chemotherapy exposure on pregnancy outcomes in women treatedduring childhood, adolescence, or young adulthood (CAYA).Data sources: MEDLINE, Embase, and the Cochrane Library from 1990 to April 2023.Methods: All studies reporting on pregnancy outcomes in adult females who had received chemotherapy orchemoradiotherapy during CAYA (<25 years) were included. The primary outcome was the live-birth rate. Oneof the secondary outcomes was preterm birth. For each outcome, a random-effect frequentist network metaanalysis(NMA) was carried out to estimate the risk ratios with 95 % confidence intervals. Sensitivity analyseswere conducted by excluding studies at high risk of bias and the leave-one-out method.Results: Eight studies were included in the meta-analysis on live-birth rates: 3,997 females became pregnant,leading to 2,878 live births. The NMA showed moderate heterogeneity or inconsistency (τ2 = 0.012, I2 = 58 %[11 %; 80 %]) and did not show any significant impact of treatments on live-birth rate. Six studies reported atotal of 125 preterm births out of 1,976 started pregnancies and were included in the NMA (τ2 = 0.07, I2 = 19 %[0 %; 62 %]). Chemoradiotherapy was significantly associated with a higher risk of preterm birth whencompared to the control group (3.44 [1.94; 6.09]) and the chemotherapy group (1.93 [1.19; 3.15]). Chemotherapyalone was associated with a statistically higher risk of preterm birth compared to the control group (1.78[1.01; 3.13]).Conclusion: Although live-birth rate was similar in pregnant women with a history of CAYA chemotherapy orchemoradiotherapy, preterm birth was significantly increased
La historia debe mirarse en los ojos del mestizaje: el ejemplo de La Réunion (océano Índico)
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Les petites îles de Méditerranée, derniers refuges de biodiversité littorale
No full textInternational audienceAvec 11 000 iles et ilots dont 250 habités, la Méditerranée abrite l’un des plus vastes archipels au monde. Ses iles forment une constellation unique d’écosystèmes abritant nombre d’espèces rares ou en voie d’extinction. Dès lors, ces territoires isolés et assez peu fréquentés jouent un rôle capital dans la conservation de la biodiversité méditerranéenn
Cancer du sein chez la femme en âge de procréer : problématiques autour du rôle des hormones
No full textInternational audienceBreast cancer affects 5% of women of childbearing age, accounting for 30% of cancer cases in this population. These cancers are often more aggressive with a less favorable prognosis in younger women. Hormonal exposure plays a key role in the development of this cancer, although the specific impact of certain exposures, such as hormonal contraception or ovarian stimulation treatments, remains debated. Studies on the link between hormonal contraception and breast cancer risk present contradictory results. Some suggest a slight increase in risk, particularly after prolonged use, while others find no significant association. Regarding assisted reproductive technology, data show no increased risk of breast cancer after ovarian stimulation. For women with breast cancer, fertility preservation is possible before the implementation of gonadotoxic treatments without significantly impacting the risk of recurrence. Pregnancy after breast cancer, including hormone-dependent cancer, is not associated with a higher risk of recurrence. Lastly, women with BRCA mutations would face an increased risk of reduced ovarian reserve, but fertility preservation, as well as the use of contraception or hormone replacement therapy, can be considered in this high-risk population
Territorialiser le symbole : une recherche-projet autour des pictogrammes liés à la prévention des risques climatiques
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Linking Data & Publications in Social Science and Humanities: the role of infrastructures in the French national context
No full textInternational audienceIn SSH (Social Science and Humanities) the link between data and publication can be seen from different angles depending on its potential use. The first use that comes to mind is to cite a dataset in a publication for the purposes of scientific verification. It can be done in a number of ways, from a simple text citation, both in the publication or in the description of a dataset, to a PID (Persistent IDentifier) in a specific metadata. Another possible type of link would be to show multimedia material (e.g. illustration, table, soundtrack, etc.) in a publication. Finally, in another vein, data papers can be considered as a case of linking data and publications.At a national level, an ecosystem of repositories and publication platforms are involved in the process of creating links between data and publications. More specifically, as part of two national projects (HALiance and COMMONS), four infrastructures are working together on SSH resources: Huma-Num (Data repository NAKALA), CCSD (Open Archive for research papers - HAL-SHS), OpenEdition (Publication Platforms for books and journals) and Métopes (Publishing Process). A study of the content of the different platforms carried out at the beginning of these projects showed that link-building practices already existed. Unsurprisingly, the study illustrated the diversity of the means used to create the above-mentioned links, and the fact that they are generally unidirectional.What role can infrastructures play in this area? First of all, there is a need to simplify things for users by building bridges between platforms. For instance, when a research paper referring to a dataset in NAKALA is deposited in HAL-SHS, it would be convenient to have direct access to the dataset from the HAL environment. Similarly, to include multimedia material in a book from OpenEditionBook may require access to the files in NAKALA, which represents a different level of granularity. This means that it is necessary to work on seamless integration between the platforms; in particular by working on the consistency of information systems, developing specific APIs, and then finally by adapting interfaces.Another crucial role of infrastructures is to guarantee the consistency of link information and to disseminate it in a standardised way. This requires automated communication between platforms to be able, for example, to create reciprocal links and maintain them over time: for instance, what happens to the link if the data disappears from the repository or if a new version is created?This process which involves adaptations at various levels, both technical and organisational, did not start from scratch. A POC (Proof of Concept) of creating links between NAKALA and HAL-SHS was performed as part of the European project EOSC-Pillar. This enabled us to determine important issues to be resolved. It also helped us to identify standards that are emerging on this topic: in this regard, it was decided to use the COAR Notify protocol for communication between the platforms and the SCHOLIX standard to disseminate data-publication links which is supported by DataCite and Crossref and used in the European context by OpenAire.This work is well advanced and the link between the HAL-SHS archive and the NAKALA repository is already operational on the development platforms and is about to be put into production. This work will serve as the basis for the link between the NAKALA repository and the OpenEdition platforms, which will also use a structured standard developed by Métopes (COMMONS TEI-Publishing) for integrating data directly into a publication.At this stage of the projects HALiance and COMMONS, communication between the various platforms via the COAR-notify protocol has been standardised and stabilised. This makes it possible to consider communication with other platforms in the national ecosystem, such as the national repository RDG (Recherche Data Gouv), which uses the same protocol. Technically, there is still work to be done: especially a better version management for publications and datasets and a better implementation of the SCHOLIX standard. Finally, it will be necessary to improve the integration between platforms through a potential common authentication, for instance. However, the key to successfully implementing the link between data and publications lies in informing and training future users, which is an important part of our projects
