HAL Collection UNC (Univ. de la Nouvelle Calédonie)
Not a member yet
7579 research outputs found
Sort by
Seroprevalence of dengue, Zika, and chikungunya in São Sebastião, Brazil (2020–2021): a population-based survey
No full textInternational audienceBackground: Urban arboviruses pose a significant global burden, particularly in tropical regions like Brazil. São Sebastião, a lower-middle-class urban area just 26 km from the Brazilian capital, is an endemic area for dengue. However, asymptomatic cases may obscure the actual extent of the disease. In this study, we measured the seroprevalence of dengue, Zika virus, and chikungunya, and compared these findings with surveillance data.Methods: A cross-sectional study was conducted involving 1,535 households. ELISA serological tests were performed to detect IgM and IgG antibodies against dengue, Zika virus, and chikungunya. History of previous exposure to arboviruses, data on age, gender, and education level were collected through a questionnaire. Participants who tested positive for IgM and/or IgG were classified as soropositive. Statistical analyses included tests for normality, associations, mean comparisons, and correlations. Positive serological results were compared with cases captured by local epidemiological surveillance.Results: The study included 1,405 individuals, divided into two groups related to pre-pandemic and pandemic COVID-19 phases. Among participants, 0.7% to 28.8% self-reported history of dengue, Zika, or chikungunya. However, the estimated overall seroprevalence was 64.3% (95% CI: 61.8–66.7) for dengue virus, 51.4% (95% CI: 48.8–53.9) for Zika virus, and 5.4% (95% CI: 4.4–6.7) for chikungunya virus. Multiple arboviruses were noted at 4.0% (95% CI: 3.1–5.1). Advancing age and lower education were associated with higher exposure to arboviruses (p < 0.05). The estimated number of urban arboviral infections was 84 times higher than reported cases.Conclusions: The large gap between seroprevalence estimates and cases captured by epidemiological surveillance suggests a silent circulation of arboviruses, highlighting the need for comprehensive serological surveys in endemic regions. Addressing these discrepancies is crucial for effective resource allocation and implementation of public health interventions
MOVE Ô: study of children’s lifestyles in Oceania
No full textInternational audienceChildhood obesity is a major public health concern in the Pacific Islands, where over 50% of adults are overweight and noncommunicable diseases account for over 80% of deaths. However, few data are available on children’s stature, and very few studies have focused on the determinants/risk factors that may explain this overweight. The MOVE Ô study aims to describe the lifestyle (physical activity, sleep, and diet) of Oceanian children using qualitative methods (biometric measurements, digital application, accelerometers, self-administered questionnaires, direct observation) and quantitative methods (individual interviews). The pilot phase was conducted with 10-year-old children from Wallis and Futuna, their parents, and teachers to gain a comprehensive understanding of the children’s lifestyle as well as the environment in which they grow up (school, family, and community settings). The findings highlight a level of physical activity well above the WHO recommendations for this age group and the presence of numerous sports facilities in proportion to the size of the territory. The students’ sleep duration is barely sufficient (an average of 9 hours), and screen use appears to be controlled. However, the study reveals a highly unvaried diet, with an almost complete absence of fruit and vegetable consumption. Additionally, 34% of the children surveyed are obese. Sufficient physical activity alone is not enough to compensate for an inadequate diet. A more in-depth study of dietary patterns is necessaryto develop more effective prevention strategies and guide public policies to ensure a healthier future for children
Physical activity behavior of adolescents living in the Pacific Island countries and territories (PICTs) and its association with weight status: cross-sectional study using accelerometry assessment in New Caledonia
No full textInternational audienceObjectives of the paperPacific Island Countries and Territories (PICTs) have undergone rapid socio-economic changes, especially since the middle of the 20th century. Globalization induced important modifications in terms of islanders’ lifestyle [Malcom 1953]. From a rural way of life, mainly based on agriculture and its rhythms on daily life, many of them tend now to have a modernized urban way of life that is closer to a Western lifestyle [Coynes et al 2000].This transition has had an impact on nutrition since the access to processed chip food is easy compared to what have to be done to produce food in a traditional system [Nedjar-Guerre et al 2023; Coynes et al 2000]. The impact has also been seen on physical activity (PA), which was practiced naturally and regularly as a result of the traditional way of life [Zongo et al 2017]. As a consequence, islanders’ health has suffered from these lifestyle changes, especially regarding non-communicable diseases and the associated factors including overweight and obesity.Children and adolescents living in PICTs are not spared from the obesity issue. Indeed, obesity prevalence can be up to 20% in children [NCD Risk Factor Collaboration (NCD-RisC) 2007] and up to 30% in adolescents [Frayon et al 2020]. Interventions and awareness-raising campaigns are organized for young people, often in schools [Bertrand-Protat et al 2024]. Their main objective is to tackle the obesity issue through PA by encouraging them to be more active. Previous studies have assessed PA in adolescents living in PICTs, precisely in New Caledonia [Wattelez et al 2021]. Thanks to questionnaires, the authors found that about 66% of the adolescent participants performed an average of at least 60 min PA per day but there were notable differences across sex, ethnic community and place of living. A small association was highlighted between being active ≥ 60 min/day and being overweight or obese [Wattelez et al 2021].While PA was assessed with subjective measures in this previous study, i.e. with questionnaires, researchers have now access to objective measures of PA through accelerometer devices that are widely used in the scientific community. This kind of data provide a lot of information with a fine granularity. For instance, Diaz et al. used information collected by GENEActiv accelerometers to get PA day clusters of children, and then estimate if a school intervention led the participants to be more active [Diaz et al 2020].As technology and data algorithms are more and more performant, it is essential to use these advances to better understand the behavior of the populations and to identify which dimensions of PA are the more important to tackle overweight and obesity. The aim of this study is to: 1) assess PA behavior of adolescents living in a PICT with objective measures; 2) identify components of PA that are the more associated with adolescents’ weight status; 3) compare with studies that have previously study similar populations.MethodsData collectionOur study was a part of project involving more than 1000 adolescents schooling in eight different schools of New Caledonia, selected in the three provinces (Northern Province, Southern Province and Loyalty Islands Province). The selection of the schools was based on a representative repartition between rural and urban (37% and 63% respectively) and a sufficient school size (n > 200).Data were collected from July 2018 to April 2019 during class time. All the participants answered to questionnaires designed to get information about their lifestyle and habits. About 30 participants (according to the number of devices available) per school were randomly selected to wear a GENEActiv accelerometer device (Activinsights Ltd, Kimbolton, UK) for 7 consecutive days, or more.The participants were also measured regarding their height (to the nearest 0.1 cm using a portable stadiometer: Leicester Tanita HR 001, Tanita Corporation, Tokyo, Japan) and weight (to the nearest 0.1 kg with an impedance scale: Tanita HA 503, Tanita Corporation). From these data, we computed BMI (weight [kg]/height [m]²) and deduced their weight status according to the International Obesity Task Force (IOTF) standard [Cole et al 2012].Processing of accelerometer dataAccelerometer data was processed according to the method described in [Diaz et al 2020], that enabled differentiating the time and the number of bouts spent in sedentary activity, light PA and moderate to vigorous PA (MVPA).For each PA level (sedentary, light and MVPA), we use several indicators extracted from accelerometer information computed for weekdays, weekends and full week: mean, standard deviation, median, range, minimum, maximum, total duration for the 3 days with the highest values, etc.First, descriptive statistics and statistical test according to sociocultural factors provide information about the factors associated with the most common PA indicators. Then, the data is processed with statistical methods for selection of variables in order to find the most predictive PA indicators. We plan to use selection by regression and by support vector regression.Main resultsSimilarly to previous studies, MVPA time average was higher in males than in females for the full week (p < 0.001), weekdays (p < 0.001) and weekend (p = 0.015). However, there was no differences according to sex for the other PA levels. Rural adolescents were more active than the urban ones with a higher MVPA time average for the full week (p = 0.002), weekdays (p = 0.038) and weekend (p = 0.002). Rural adolescents had also a higher light PA time average for the full week (p < 0.00) and weekdays (p < 0.001). Ethnic community was a significant factor to explain the time spent in different PA levels. For instance, MVPA time average was higher in Melanesian adolescents for the full week (p < 0.001) and weekdays (p < 0.001) but not for weekend (p = 0.057). The observation was similar regarding the light PA average. There were no significant differences in PA behavior according to IOTF weight status.Data processing regarding the selection of variables is yet ongoing but it seems that the place of living (i.e., rural and urban) and indicators about light PA and (probably) sedentary times are the most predictive for IOTF z-score.The results we expect from this study would contribute to better understand which components of PA are to be targeted in education or intervention program to tackle the overweight and obesity pandemic in the Pacific.ReferencesBertrand-Protat, S., Wattelez, G., Frayon, S., Caillaud, C. et Galy, O. (2024) . Encourager la pratique de l’activité physique chez les enfants du Pacifique, un moyen efficace pour prévenir l’obésité infantile ? Étude pilote en milieu scolaire sur le territoire des îles de Wallis-et-Futuna. Santé Publique, vol. 36(HS2), 71-81. https://doi.org/10.3917/spub.hs2.2024.0071.Cole TJ, Lobstein T. Extended international (IOTF) body mass index cut-offs for thinness, overweight and obesity: extended international BMI cut-offs. Pediatr Obes. 2012;7:284-294.Coynes T, Hugues R, Langi S. Lifestyle diseases in Pacific communities. Secratariat of the Pacific Community. 2000.C. Díaz, O. Galy, C. Caillaud and K. Yacef, "A Clustering Approach for Modeling and Analyzing Changes in Physical Activity Behaviors From Accelerometers," in IEEE Access, vol. 8, pp. 224123-224134, 2020, doi: 10.1109/ACCESS.2020.3044295.Frayon S, Wattelez G, Paufique E, Nedjar-Guerre A, Serra-Mallol C, Galy O. Overweight in the pluri-ethnic adolescent population of New Caledonia: Dietary patterns, sleep duration and screen time. Lancet Reg Health – West Pac. 2020 Sep;2:100025.Malcom S. Nutritional investigations in New Caledonia. Noumea, New Caledonia, South Pacific Commission, 1953.NCD Risk Factor Collaboration (NCD-RisC). Worldwide trends in body-mass index, underweight, overweight, and obesity from 1975 to 2016: a pooled analysis of 2416 population-based measurement studies in 128·9 million children, adolescents, and adults. Lancet Lond Engl. 2017 Dec 16;390(10113):2627-42.Nedjar-Guerre A, Wattelez G, Serra-Mallol C, Frayon S, Galy O (2023) Adolescent screen time and unhealthy food consumption in the context of the digital development in New Caledonia. PLoS ONE 18(5): e0285374. https://doi.org/10.1371/ journal.pone.0285374Wattelez G, Frayon S, Caillaud C and Galy O (2021) Physical Activity in Adolescents Living in Rural and Urban New Caledonia: The Role of Socioenvironmental Factors and the Association With Weight Status. Front. Public Health 9:623685. doi: 10.3389/fpubh.2021.623685Zongo P, Frayon S, Antoine-Jonville S, et al. Anthropometric Characteristics and Physical Fitness in Rural and Urban 11- to 16-Year-Old Melanesian Adolescents: A Cross-sectional Study in New Caledonian Schools. Asia Pacific Journal of Public Health. 2017;29(7):589-598. doi:10.1177/101053951773541
Impact du statut des médicaments de thérapie innovante dans la réglementation européenne sur leur coût de production : le cas des cellules souches hématopoïétiques
No full textInternational audienceObjectives: The therapeutic promises of somatic cell and gene therapy (Advanced Therapy Medicinal Products - ATMP) and the significant current or future costs of such therapies raise questions about the impact of European health policy on these expenses. Regulation 1394/2007 currently imposes the medicinal product status on many treatments derived from cell therapy. This study aims to determine the impact of new regulations on manufacturing costs of cell therapy treatments, used as ATMP.Methods: In our study, using counterfactual reasoning, we analyze the consequences that a change of status would have on the hematopoietic stem cells (HSC) used for treatment of leukemia.Results: Under the existing status of cell transplantation (CT, Directive 2004/23/EC), the annual production cost of these cell therapy products (CTP) in France is estimated at euro 5.6 million. If the HSC used in leukemia indication were under the medicinal product status of ATMP, the cost would rise to approximately euro 9.9 million, without accounting for expenses related to facilities, which are much higher for ATMP than for CT.Conclusion: This additional burden for manufacturers must be weighed against the theoretical benefits for patients, such as reduced contamination risk. Given the very low contamination levels reported by facilities using transplant standards, the extra cost seems excessive and could hinder the development of new advanced therapies. Furthermore, it raises the need to adapt existing Good Manufacturing Practice guidelines for autologous products or those made from a single donor for a single patient, ensuring safety and cost reduction, which should encourage further development of cell therapy.ObjectifsLes promesses thérapeutiques de la thérapie génique et des cellules somatiques (Médicaments de Thérapie Innovante – MTI) et les coûts actuels ou futurs significatifs de ces thérapies soulèvent des questions quant à l’impact des politiques de santé européennes sur ces dépenses. Le règlement 1394/2007 impose actuellement le statut de médicament à de nombreux traitements issus de la thérapie cellulaire. Cette étude vise à déterminer l’impact des nouvelles réglementations sur les coûts des traitements issus de la thérapie cellulaire, utilisés comme MTI.MéthodesDans notre étude, à l’aide du raisonnement contrefactuel, nous analysons les conséquences d’un changement de statut des cellules souches hématopoïétiques (CSH) utilisées pour le traitement de la leucémie.RésultatsSous le statut actuel de la transplantation cellulaire, le coût annuel de production des produits de thérapie cellulaire (PTC) est estimé à 5,6 millions d’euros. Si les CSH utilisées dans l’indication de la leucémie relevaient du statut de médicament sous les ATMP, le coût augmenterait à environ 9,9 millions d’euros, sans compter les frais liés aux infrastructures, bien plus élevés pour les ATMP que pour les CT.ConclusionCe fardeau supplémentaire pour les fabricants doit être pondéré par les bénéfices théoriques pour les patients, tels que la réduction du risque de contamination. Étant donné les très faibles niveaux de contamination rapportés par les installations utilisant les normes de transplantation, le surcoût semble excessif et pourrait freiner le développement des nouvelles thérapies avancées. De plus, cela soulève la nécessité d’adapter les directives actuelles des Bonnes Pratiques de Fabrication (BPF) pour les produits autologues ou provenant d’un seul donneur destiné à un seul patient, afin d’assurer la sécurité et de réduire les coûts, ce qui devrait encourager le développement futur de la thérapie cellulaire
Training Local Models from Reanalysis Data to Estimate Reference Evapotranspiration with Fewer Onsite Sensors, an Evaluation in West Africa
No full textThis study addresses the critical need for accurate reference evapotranspiration (ET0) estimation in data-scarce environments such as West Africa, where rapid population growth and climate change intensify water resource challenges. Traditionally, computing ET0 with the FAO-56 Penman-Monteith method requires multiple meteorological inputs—such as solar radiation, humidity, and wind speed—collected from costly, fully instrumented weather stations. However, the availability and maintenance of such equipment can be prohibitive in remote regions. To overcome these constraints, we explore the potential of machine learning (ML), specifically XGBoost (XGB) models, trained on NASA Power climate reanalysis datasets. Our approach relies on a limited subset of easily measured in situ variables—daily minimum and maximum temperatures and rainfall—to estimate ET0. Departing from standard ML practices that depend on short-term, site-specific data, we leverage the extensive historical depth and broad spatial coverage of reanalysis products. We trained and validated twenty locally adapted XGB models using measurements from twenty diverse West African weather stations. Our results show that certain XGB model configurations, notably those incorporating temperature and rainfall data, can approximate ET0 estimates from the FAO-56 Penman-Monteith equation with median RMSE values frequently below 1 mm/day—levels comparable to commonly employed empirical formulas. This finding demonstrates that minimal on-site instrumentation, combined with ML and reanalysis data, can effectively support irrigation scheduling and enhance water-use efficiency under varying agro-ecological conditions. To foster broader implementation, we have released our XGB-ET0 code under the GPLv3 licence (https://github.com/SARRA-cropmodels/RF-ET0), enabling researchers and practitioners to locally train and deploy these models, thereby improving ET0 estimation and sustainable agricultural water management in resource-limited settings
Qualifier un maire de « raciste » ne dépasse pas forcément les limites admissibles de la liberté d'expression
No full textInternational audienc
Mediterranean islands as refugia for elasmobranch and threatened fishes
No full text\ₑprint: https://onlinelibrary.wiley.com/doi/pdf/10.1111/ddi.13937International audienceAim The Mediterranean Sea is one of the most anthropized seas in the world but also a marine biodiversity hotspot with many fish species under threat. The main goal of the study is to test whether on the heavily fished and anthropized Mediterranean coast, the less impacted Corsica and Balearic Islands, can be considered as refugia for threatened and elasmobranch fishes independently of protection by marine reserves. Location The French Mediterranean coast and three north-western Mediterranean islands: Corsica and also Mallorca and Minorca from the Balearic archipelago. Methods We performed 187 fish surveys using environmental DNA metabarcoding on three islands and 109 along the continental coast. Of the 78 surveys on islands 22 correspond to no-take marine reserves and of the 109 continental surveys 26 were carried out within reserves. After eDNA filtration, extraction, amplification, and sequencing we estimated the number of fish species but also the number commercial, threatened and elasmobranch fish species on each sample. We then performed an ANOVA by permutation to test the effect of insularity and protection on these four biodiversity metrics. We also modelled these four biodiversity metrics as a function of protection and human pressure but also environmental, habitat and sampling conditions. We also built species accumulation curves to obtain asymptotes representing the potential regional pools for each species category on both island and continental coasts. Results We obtained a total of 175,982,610 reads over the 187 eDNA samples that were assigned to 153 fish species including 17 elasmobranch species among which 7 were only detected on islands. We observed a higher total fish richness on continental than island surveys regardless of protection but a higher threatened and elasmobranch fish richness on the island than on continental surveys. We obtained a significant, negative and predominant human gravity impact on the diversity of elasmobranch species. The modelled asymptote reached 148 teleostean fish species on islands and 196 on the continental coastline with a very similar rate of diversity increase with sampling effort but the shape of the species accumulation curves differed markedly for elasmobranchs with a stronger increase in diversity with sampling effort on islands. Main Conclusions Our findings highlight that Mediterranean islands can be refugia for sharks and rays but also threatened fishes in this overexploited region. Our results also suggest that reducing or banning trawling activities may play a key role for conserving vulnerable fishes, beyond the benefits of no-take marine reserves, which appear limited on these large home-range species
LUMA: A Benchmark Dataset for Learning from Uncertain and Multimodal Data
No full textInternational audienceMultimodal Deep Learning enhances decision-making by integrating diverse information sources, such as texts, images, audio, and videos. To develop trustworthy multimodal approaches, it is essential to understand how uncertainty impacts these models. We propose LUMA, a unique benchmark dataset, featuring audio, image, and textual data from 50 classes, for learning from uncertain and multimodal data. It extends the well-known CIFAR 10/100 dataset with audio samples extracted from three audio corpora, and text data generated using the Gemma-7B Large Language Model (LLM). The LUMA dataset enables the controlled injection of varying types and degrees of uncertainty to achieve and tailor specific experiments and benchmarking initiatives. LUMA is also available as a Python package including the functions for generating multiple variants of the dataset with controlling the diversity of the data, the amount of noise for each modality, and adding out-of-distribution samples. A baseline pre-trained model is also provided alongside three uncertainty quantification methods: Monte-Carlo Dropout, Deep Ensemble, and Reliable Conflictive Multi-View Learning. This comprehensive dataset and its benchmarking tools are intended to promote and support the development, evaluation, and benchmarking of trustworthy and robust multimodal deep learning approaches. We anticipate that the LUMA dataset will help the ICLR community to design more trustworthy and robust machine learning approaches for safety critical applications
THE PLASTISPHERE OF PLASTIC POLLUTION IN NEW CALEDONIA: A CARRIER FOR METAL- AND ANTIBIOTIC-RESISTANT CORAL REEF PATHOGENS
No full textInternational audiencePlastics threaten marine ecosystems, yet their impact on New Caledonia's reefs (South Pacific) remains understudied. The plastisphere may harbor harmful bacteria, including coral pathogens like Vibrio spp., and contribute to antibiotic and metal resistance, jeopardizing coral health. Macroplastics were collected from two coastal sites in New Caledonia along an 800 m by 30 m transect. Plastics were identified using Fourier-transform infrared spectroscopy, biofilms analyzed via scanning electron microscopy, and metal content quantified by ICP-EOS. Bacteria from the biofilm were isolated and identified using MALDI-TOF mass spectrometry and 16S rDNA sequencing. We also tested Vibrio isolates for antibiotic and metal resistance. We quantified a mean rate of 760 plastics/ km2 of which predominant polymers were polyethylene terephthalate (23%), polypropylene (21%), polyethylene (15%), and Polyvinyl chloride (15%). Biofilms hosted bacteria, diatoms, and cyanobacteria, with cultivable flora ranges from 3.104 to 1.106 CFU.ml-1. Vibrio spp. accounted up to to 6.104 CFU.ml-1. The coral pathogen, V. alginolyticus averaged 1.9 104 CFU.ml-1. Moreover, biofilms contained heavy metals, with nickel and cobalt, up to 25 μmol/g 20 μmol/g, respectively. Vibrio spp. isolates exhibited resistance to a metal mixture (50 ppm nickel,10 ppm cobalt, 5 ppm chromium, 100 ppm manganese) and four antibiotics (Ceftazidime (10 μg), la Piperacilline-tazobactam (30-6 μg), Ciprofloxacine (5 μg), Tetracycline (30 μ)). This study confirms that plastics act as reservoirs for harmful bacteria, facilitating their persistence and possibly their spread. As carriers of resistant pathogens, they pose a significant threat to marine ecosystems. Reducing plastic pollution is critical for coral reef conservatio
Halophyte plant species as a reservoir of extremophile microorganisms useful for the implementation of bio-augmented phytoremediation strategies and/or future biotechnological developments
No full textInternational audienceWith more than 5 million sites affected by heavy metals (HMs) and an annual associated economic loss of nearly $10 billion worldwide, limiting the spread of contaminants in the environment became a matter of crucial concern for most countries. Since marine and coastal ecosystems represent important economic, social and cultural resources for populations worldwide (including islanders), efficient solutions of bioremediation applied to saline soils must be developed. Hence, scientists and engineers must unit their efforts in order to develop nature-based solutions of decontamination, which would offer economic and ecological solutions to remove HMs from polluted soils and/or water. In New-Caledonia, estuaries are frequently affected by HMs (mainly Ni, Co, Cr, Mn), in part originating from mining-erosion sediments. Our work aims to characterize the cultivable microbiome of halophyte plant species naturally growing on HMs-contaminated saltmarshes. From 107 bacterial (both endophytic and rhizospheric) and 28 fungal (endophytic) isolates, some showed a great potential for the bio-augmentation of HMs phytoremediation using halophytes. Indeed, these isolates could grow in high salt- and HM-concentrations and promote plant growth via phytohormones production and plant nutrition facilitation (thus demonstrating PGP effects). Interestingly some of those isolates also displayed the ability to produce exopolysaccharides and/or biofilms. Further greenhouse experiments will elucidate the effective role of these isolates in the plant-stress alleviation and growth promotion, with and without the natural microbiome