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2.
Sci Rep ; 14(1): 15596, 2024 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971939

RESUMO

Common beans (CB), a vital source for high protein content, plays a crucial role in ensuring both nutrition and economic stability in diverse communities, particularly in Africa and Latin America. However, CB cultivation poses a significant threat to diseases that can drastically reduce yield and quality. Detecting these diseases solely based on visual symptoms is challenging, due to the variability across different pathogens and similar symptoms caused by distinct pathogens, further complicating the detection process. Traditional methods relying solely on farmers' ability to detect diseases is inadequate, and while engaging expert pathologists and advanced laboratories is necessary, it can also be resource intensive. To address this challenge, we present a AI-driven system for rapid and cost-effective CB disease detection, leveraging state-of-the-art deep learning and object detection technologies. We utilized an extensive image dataset collected from disease hotspots in Africa and Colombia, focusing on five major diseases: Angular Leaf Spot (ALS), Common Bacterial Blight (CBB), Common Bean Mosaic Virus (CBMV), Bean Rust, and Anthracnose, covering both leaf and pod samples in real-field settings. However, pod images are only available for Angular Leaf Spot disease. The study employed data augmentation techniques and annotation at both whole and micro levels for comprehensive analysis. To train the model, we utilized three advanced YOLO architectures: YOLOv7, YOLOv8, and YOLO-NAS. Particularly for whole leaf annotations, the YOLO-NAS model achieves the highest mAP value of up to 97.9% and a recall of 98.8%, indicating superior detection accuracy. In contrast, for whole pod disease detection, YOLOv7 and YOLOv8 outperformed YOLO-NAS, with mAP values exceeding 95% and 93% recall. However, micro annotation consistently yields lower performance than whole annotation across all disease classes and plant parts, as examined by all YOLO models, highlighting an unexpected discrepancy in detection accuracy. Furthermore, we successfully deployed YOLO-NAS annotation models into an Android app, validating their effectiveness on unseen data from disease hotspots with high classification accuracy (90%). This accomplishment showcases the integration of deep learning into our production pipeline, a process known as DLOps. This innovative approach significantly reduces diagnosis time, enabling farmers to take prompt management interventions. The potential benefits extend beyond rapid diagnosis serving as an early warning system to enhance common bean productivity and quality.


Assuntos
Aprendizado Profundo , Phaseolus , Doenças das Plantas , Phaseolus/virologia , Phaseolus/microbiologia , Doenças das Plantas/virologia , Doenças das Plantas/microbiologia , Agricultura/métodos , Folhas de Planta/virologia , Folhas de Planta/microbiologia , África , Colômbia
3.
Nat Commun ; 15(1): 5205, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918383

RESUMO

The extent of aerial flows of insects circulating around the planet and their impact on ecosystems and biogeography remain enigmatic because of methodological challenges. Here we report a transatlantic crossing by Vanessa cardui butterflies spanning at least 4200 km, from West Africa to South America (French Guiana) and lasting between 5 and 8 days. Even more, we infer a likely natal origin for these individuals in Western Europe, and the journey Europe-Africa-South America could expand to 7000 km or more. This discovery was possible through an integrative approach, including coastal field surveys, wind trajectory modelling, genomics, pollen metabarcoding, ecological niche modelling, and multi-isotope geolocation of natal origins. The overall journey, which was energetically feasible only if assisted by winds, is among the longest documented for individual insects, and potentially the first verified transatlantic crossing. Our findings suggest that we may be underestimating transoceanic dispersal in insects and highlight the importance of aerial highways connecting continents by trade winds.


Assuntos
Borboletas , Voo Animal , Animais , Borboletas/fisiologia , Voo Animal/fisiologia , Vento , Ecossistema , América do Sul , Europa (Continente) , Migração Animal/fisiologia , Pólen , África , Distribuição Animal
4.
PLoS One ; 19(5): e0298154, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38809901

RESUMO

BACKGROUND: Ovarian cancer is a challenging disease to diagnose and treat effectively with five-year survival rates below 50%. Previous patient experience research in high-income countries highlighted common challenges and opportunities to improve survival and quality of life for women affected by ovarian cancer. However, no comparable data exist for low-and middle-income countries, where 70% of women with the disease live. This study aims to address this evidence gap. METHODS: This is an observational multi-country study set in low- and middle-income countries. We aim to recruit over 2000 women diagnosed with ovarian cancer across multiple hospitals in 24 countries in Asia, Africa and South America. Country sample sizes have been calculated (n = 70-96 participants /country), taking account of varying national five-year disease prevalence rates. Women within five years of their diagnosis, who are in contact with participating hospitals, are invited to take part in the study. A questionnaire has been adapted from a tool previously used in high-income countries. It comprises 57 multiple choice and two open-ended questions designed to collect information on demographics, women's knowledge of ovarian cancer, route to diagnosis, access to treatments, surgery and genetic testing, support needs, the impact of the disease on women and their families, and their priorities for action. The questionnaire has been designed in English, translated into local languages and tested according to local ethics requirements. Questionnaires will be administered by a trained member of the clinical team. CONCLUSION: This study will inform further research, advocacy, and action in low- and middle-income countries based on tailored approaches to the national, regional and global challenges and opportunities. In addition, participating countries can choose to repeat the study to track progress and the protocol can be adapted for other countries and other diseases.


Assuntos
Países em Desenvolvimento , Neoplasias Ovarianas , Qualidade de Vida , Humanos , Feminino , Neoplasias Ovarianas/terapia , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/diagnóstico , Inquéritos e Questionários , Ásia/epidemiologia , África/epidemiologia , América do Sul/epidemiologia , Taxa de Sobrevida , Adulto , Pessoa de Meia-Idade
5.
BMC Plant Biol ; 24(1): 476, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816799

RESUMO

BACKGROUND: Interest in the evolution of climatic niches, particularly in understanding the potential adaptive responses of species under climate change, has increased both theoretically and within macroecological studies. These studies have provided valuable insights into how climatic traits of species influence their niche evolution. In this study, we aim to investigate whether niche conservatism plays a role in the species diversification of Nymphaea, a group of aquatic plants with a cosmopolitan distribution that is facing severe habitat loss. We will use climatic models and phylogenetic data for 23 species to reconstruct Nymphaea's niche evolution, measure niche overlap, and assess disparity through time while testing for evolutionary models. RESULTS: There was a lot of overlap in niches both within and between groups, especially for species that can be found in many places. The breadth and peaks of the niche profile varied depending on the bioclimatic variables, which suggested that the species evolved differently to cope with changes in climate. The analysis also showed that evolutionary changes happened across the phylogeny, with weak to moderate signals. The morphological disparity index (MDI) values indicated that there were disparities within subclades over time but not between or among them. Niche reconstruction and evolution analysis revealed both convergent and divergent evolution among various variables. For example, N. immutabilis, N. atrans, N. violancea, and N. nouchali evolved towards intermediate temperatures for bio2 and bio3 (isothermity) while moving towards extreme temperatures for bio8 and bio9 (wettest and driest average quarterly temperatures). CONCLUSION: Our study will improve our understanding of how changes in climatic niches are potentially driving the evolution of Nymphaea. It has significant scientific implications for the limits, assemblages, evolution, and diversification of species. This information is crucial for the ongoing efforts of conservation and management, particularly considering the inevitable effects of climate change.


Assuntos
Evolução Biológica , Clima , Ecossistema , Filogenia , América do Sul , Austrália , África , Mudança Climática
6.
BMJ Glob Health ; 9(5)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724069

RESUMO

BACKGROUND: Although the levels of demand for family planning satisfied (DFPS) have increased in many countries, cultural norms remain a significant barrier in low- and middle-income countries. In the context of multireligious African countries, our objective was to investigate intersectional inequalities in DFPS by modern or traditional contraceptives according to religion and women's empowerment. METHODS: Analyses were based on Demographic and Health Surveys carried out between 2010 and 2021 in African countries. Countries with at least 10% of Muslims and Christians were selected to analyse inequalities in family planning. The religious groups were characterised by wealth, area of residence, women's age and women's empowerment. The mean level of empowerment was estimated for each religious group, and multilevel Poisson regression was used to assess whether DFPS varied based on the level of women's empowerment among Muslims and Christians. RESULTS: Our study sample of 14 countries comprised 35% of Muslim and 61% of Christian women. Christians had higher levels of empowerment across all three domains compared with Muslims and women with no/other religion. DFPS was also higher among Christians (57%) than among Muslims (36%). Pooled analysis indicated a consistent association between DFPS and women's empowerment, with higher prevalence ratios among Muslims than Christians, especially in the decision-making domain. CONCLUSIONS: The gap between Muslims and Christians in DFPS significantly reduced as the level of empowerment increased. It highlights the importance of understanding and addressing cultural factors sensibly and respectfully to satisfy the demand for family planning services.


Assuntos
Cristianismo , Empoderamento , Serviços de Planejamento Familiar , Islamismo , Humanos , Feminino , Adulto , Adulto Jovem , Pessoa de Meia-Idade , África/etnologia , Adolescente , Fatores Socioeconômicos
7.
Curr Biol ; 34(6): R251-R254, 2024 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-38531320

RESUMO

An analysis of over 1 million old-growth tropical forest trees reveals that ∼2.2% of species comprise 50% of the individuals in Africa, Amazonia, and Southeast Asia, suggesting that the ecological mechanisms underpinning tree community assembly are ubiquitous across the tropics.


Assuntos
Árvores , Clima Tropical , África , Brasil , Ecossistema , Florestas
8.
Mol Biol Evol ; 41(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38349332

RESUMO

Modern humans originated in Africa 300,000 yr ago, and before leaving their continent of origin, they underwent a process of intense diversification involving complex demographic dynamics. Upon exiting Africa, different populations emerged on the four other inhabited continents, shaped by the interplay of various evolutionary processes, such as migrations, founder effects, and natural selection. Within each region, continental populations, in turn, diversified and evolved almost independently for millennia. As a backdrop to this diversification, introgressions from archaic species contributed to establishing different patterns of genetic diversity in different geographic regions, reshaping our understanding of our species' variability. With the increasing availability of genomic data, it has become possible to delineate the subcontinental human population structure precisely. However, the bias toward the genomic research focused on populations from the global North has limited our understanding of the real diversity of our species and the processes and events that guided different human groups throughout their evolutionary history. This perspective is part of a series of articles celebrating 40 yr since our journal, Molecular Biology and Evolution, was founded (Russo et al. 2024). The perspective is accompanied by virtual issues, a selection of papers on human diversification published by Genome Biology and Evolution and Molecular Biology and Evolution.


Assuntos
Evolução Biológica , Genômica , Humanos , Filogenia , África , Genética Humana , Variação Genética
9.
Evolution ; 78(5): 1020-1021, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38364848

RESUMO

Why do some clades diversify more than others? And what are the roles of abiotic and biotic factors in driving such unequal diversification? To explore this, Burns et al. (2024) investigate variation in body morphology in a group of freshwater fish, Characiformes, across South America and Africa. They find that habitat features such as slope, elevation, and flow rates have played a major role in the diversification of morphological variation in the Characiformes. The Neotropical lineages residing in significantly more diverse slope and elevation habitats were found to display more body shape diversity than African lineages. The authors also report that competition might have limited the morphological variation in African Characiformes compared to the Neotropical lineages. This study highlights the importance of exploring both abiotic and biotic factors when examining diversification.


Assuntos
Ecossistema , Animais , Caraciformes/genética , Caraciformes/fisiologia , América do Sul , África , Especiação Genética
10.
Evol Anthropol ; 33(3): e22022, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38270328

RESUMO

Although the evolutionary history of anthropoid primates (monkeys, apes, and humans) appears relatively well-documented, there is limited data available regarding their origins and early evolution. We review and discuss here the earliest records of anthropoid primates from Asia, Africa, and South America. New fossils provide strong support for the Asian origin of anthropoid primates. However, the earliest recorded anthropoids from Africa and South America are still subject to debate, and the early evolution and dispersal of platyrhines to South America remain unclear. Because of the rarity and incomplete nature of many stem anthropoid taxa, establishing the phylogenetic relationships among the earliest anthropoids remains challenging. Nonetheless, by examining evidence from anthropoids and other mammalian groups, we demonstrate that several dispersal events occurred between South Asia and Afro-Arabia during the middle Eocene to the early Oligocene. It is possible that a microplate situated in the middle of the Neotethys Ocean significantly reduced the distance of overseas dispersal.


Assuntos
Antropologia Física , Evolução Biológica , Fósseis , Filogenia , Animais , África , Ásia , América do Sul , Humanos , Primatas/classificação
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