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1.
Proc Natl Acad Sci U S A ; 120(14): e2218777120, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36972436

RESUMO

Food systems face new climatic and socioecological challenges and farmers need a diversity of new plant varieties to respond to these. While plant breeding is important, institutional innovations in seed systems are critical to ensure that new traits and varieties make their way into farmers' fields. This Perspective reviews the state of knowledge on seed system development, outlining insights emerging from the literature that can help navigate the way forward. We synthesize evidence on the contributions and limitations of the different actors, activities, and institutions pertaining to all seed systems smallholder farmers use, formal and informal. To do so, we structure our analysis on three functions-variety development and management, seed production, and seed dissemination-and two contextual factors-seed governance and food system drivers-that can be used to describe any seed system. Our review reveals the strengths and weaknesses of the activities of different actors along the entire chain of functions and demonstrates the multifaceted efforts to strengthen seed systems. We document that a new agenda for seed system development is taking root, based on the view that formal and farmers' seed systems are complementary. Because needs differ from crop to crop, farmer to farmer, and between agroecological and food system contexts, a variety of pathways are needed to ensure farmers' seed security. While the complexity of seed systems eludes a simple roadmap, we conclude by planting a "signpost" with principles to guide efforts to develop resilient and inclusive seed systems.


Assuntos
Melhoramento Vegetal , Sementes , Humanos , Fenótipo , Fazendeiros , Conhecimento
2.
Am J Phys Anthropol ; 175(4): 777-793, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33720412

RESUMO

OBJECTIVES: This study aims to increase the rate of correctly sexed calcined individuals from archaeological and forensic contexts. This is achieved by evaluating sexual dimorphism of commonly used and new skeletal elements via uni- and multi-variate metric trait analyses. MATERIALS AND METHODS: Twenty-two skeletal traits were evaluated in 86 individuals from the William M. Bass donated cremated collection of known sex and age-at-death. Four different predictive models, logistic regression, random forest, neural network, and calculation of population specific cut-off points, were used to determine the classification accuracy (CA) of each feature and several combinations thereof. RESULTS: An overall CA of ≥ 80% was obtained for 12 out of 22 features (humerus trochlea max., and lunate length, humerus head vertical diameter, humerus head transverse diameter, radius head max., femur head vertical diameter, patella width, patella thickness, and talus trochlea length) using univariate analysis. Multivariate analysis showed an increase of CA (≥ 95%) for certain combinations and models (e.g., humerus trochlea max. and patella thickness). Our study shows metric sexual dimorphism to be well preserved in calcined human remains, despite the changes that occur during burning. CONCLUSIONS: Our study demonstrated the potential of machine learning approaches, such as neural networks, for multivariate analyses. Using these statistical methods improves the rate of correct sex estimations in calcined human remains and can be applied to highly fragmented unburnt individuals from both archaeological and forensic contexts.


Assuntos
Restos Mortais , Determinação do Sexo pelo Esqueleto , Análise Discriminante , Antropologia Forense , Humanos , Caracteres Sexuais , Aprendizado de Máquina Supervisionado
3.
Am J Phys Anthropol ; 175(1): 128-136, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33381868

RESUMO

OBJECTIVES: The Falys-Prangle-method assesses age-related morphological changes to the sternal clavicle end (SCE), enabling the observation of mature adults from the 5th decade onwards in unburnt human skeletal remains. The aim of this study is to investigate the applicability of the Falys-Prangle-method on burnt human remains. MATERIALS AND METHODS: Fifty-two SCE of 40 cremated individuals (out of 86) from the William M. Bass collection of the Forensic Anthropology Center (Knoxville, Tennessee) of known age-at-death and sex are available for assessment. Surface topography, porosity, and osteophyte formation are evaluated, after which the calculated composite score is associated with the corresponding age range as described by Falys and Prangle. The method is also applied on an archaeological case study from Oudenburg, Belgium, dating to the Roman period. RESULTS: The assessed age ranges strongly agree with the true age ranges (α = 0.828), suggesting the Falys-Prangle-method to be applicable on burnt human remains. The case study from Oudenburg yields markedly improved age-at-death estimates, significantly enhancing our understanding of the age distribution within this community. DISCUSSION: Information on age-at-death is key in the construction of biological profiles of past individuals. The mature adult is often invisible in the archaeological record since most macroscopic age estimation methods do not distinguish beyond 46+ years old. Our study stresses the usefulness of a large-scale application of the Falys-Prangle-method, which will increase the visibility of mature adults, especially in archaeological burnt human skeletal collections, where such information is, at present, extremely difficult to obtain.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Clavícula/anatomia & histologia , Cremação/história , Adulto , Idoso , Idoso de 80 Anos ou mais , Arqueologia , Feminino , Antropologia Forense , História Antiga , Humanos , Masculino , Pessoa de Meia-Idade
4.
Sci Rep ; 12(1): 9280, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35660749

RESUMO

The high temperatures reached during cremation lead to the destruction of organic matter preventing the use of traditional isotopic methods for dietary reconstructions. Still, strontium isotope (87Sr/86Sr) and concentration ([Sr]) analyses of cremated human remains offer a novel way to assess changing consumption patterns in past populations that practiced cremation, as evidenced by a large amount of new data obtained from Metal Ages and Gallo-Roman human remains from Destelbergen, Belgium. The Gallo-Roman results show significantly higher [Sr] and a narrower interquartile range in 87Sr/86Sr (0.7093-0.7095), close to the value of modern-day seawater (0.7092). This contrasts with the Metal Ages results, which display lower concentrations and a wider range in 87Sr/86Sr (0.7094-0.7098). This typical Sr signature is also reflected in other sites and is most likely related to an introduction of marine Sr in the form of salt as a food preservative (e.g. salt-rich preserved meat, fish and fish sauce). Paradoxically, this study highlights caution is needed when using 87Sr/86Sr for palaeomobility studies in populations with high salt consumption.


Assuntos
Cremação , Isótopos de Estrôncio , Animais , Restos Mortais , Osso e Ossos/química , Dieta , Isótopos/análise , Estrôncio/análise , Isótopos de Estrôncio/análise
5.
Ecol Appl ; 21(5): 1557-72, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21830702

RESUMO

Shifting cultivation is often perceived to be a threat to forests, but it is also central to the culture and livelihoods of millions of people worldwide. Balancing agriculture and forest conservation requires knowledge of how agricultural land uses evolve in landscapes with forest conservation initiatives. Based on a case study from Quintana Roo, Mexico, and remote sensing data, we investigated land use and land cover change (LUCC) in relation to accessibility (from main settlement and road) in search of evidence for agricultural expansion and/or intensification after the initiation of a community forestry program in 1986. Intensification was through a shortening of the fallow period. Defining the sampling space as a function of human needs and accessibility to agricultural resources was critical to ensure a user-centered perspective of the landscape. The composition of the accessible landscape changed substantially between 1976 and 1997. Over the 21-year period studied, the local population saw the accessible landscape transformed from a heterogeneous array of different successional stages including mature forests to a landscape dominated by young fallows. We detected a dynamic characterized by intensification of shifting cultivation in the most accessible areas with milpas being felled more and more from young fallows in spite of a preference for felling secondary forests. We argue that the resulting landscape provides a poorer resource base for sustaining agricultural livelihoods and discuss ways in which agricultural change could be better addressed through participatory land use planning. Balancing agricultural production and forest conservation will become even more important in a context of intense negotiations for carbon credits, an emerging market that is likely to drive future land changes worldwide.


Assuntos
Agricultura , Conservação dos Recursos Naturais/métodos , Ecossistema , Árvores , Monitoramento Ambiental , México , Fatores de Tempo
6.
PLoS One ; 16(10): e0257199, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34644308

RESUMO

Cremation is a complex mortuary practice, involving a number of activities of the living towards the dead before, during, and after the destruction of the bodily soft tissues by fire. The limiting information concerning these behavioral patterns obtained from the pyre remains and/or cremation deposits prevents the reconstruction of the handling of the corpse during the burning process. This pioneering study tries to determine the initial positioning of the corpse in the pyre and assess whether the deceased was wearing closed leather shoes during cremation through isotopic (δ13C, δ18O) and infrared (ATR-FTIR) analyses of experimentally burnt pig remains, used as a proxy for humans. The results obtained show that both the position of feet on or within the pyre and the presence of footwears may moderately-to-highly influence the oxygen isotope ratios of bone apatite carbonates and the cyanamide content of calcined bone in certain situations. By forming a protective layer, shoes appear to temporarily delay the burning of the underlying pig tissues and to increase the heat-shielding effect of the soft tissues protecting the bone mineral fraction. In such case, bioapatite bone carbonates exchange oxygen with a relatively more 18O-depleted atmosphere (due to the influence of lignin-derived oxygen rather than cellulose-derived oxygen), resulting in more pronounced decrease in the δ18Ocarb values during burning of the shoed feet vs. unshoed feet. The shift observed here was as high as 2.5‰. A concomitant isotopic effect of the initial location of the feet in the pyres was also observed, resulting in a top-to-bottom decrease difference in the δ18Ocarb values of shoed feet of about 1.4‰ between each deposition level tested. Finally, the presence of cyanamide (CN/P ≥ 0.02) seems to be indicative of closed footwear since the latter creates favorable conditions for its incorporation into bone apatite.


Assuntos
Cremação , Animais , Restos Mortais/química , Osso e Ossos/química , Cadáver , Isótopos de Carbono/análise , Humanos , Isótopos de Oxigênio/análise , Sapatos , Espectroscopia de Infravermelho com Transformada de Fourier , Suínos
7.
J Ethnopharmacol ; 96(1-2): 233-48, 2005 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-15588676

RESUMO

Midwives in rural communities across the globe play an important role as primary health care providers, but few studies have documented the medicinal plants employed in this age-old practice. Semi-structured interviews were conducted with 23 midwives in seven rural communities near La Ceiba, Honduras, regarding the plants they employ during the birthing process as well as their associated beliefs. Seventy-nine different plant species used to treat 15 conditions occurring during the pregnancy, birth and postpartum stages were recorded. Most plants and uses were reported by only one or two midwives, reflecting the fact that most midwives in this region had immigrated from different parts of the country. Almost all the midwives used or knew of plant remedies for treatment of miscarriages, postpartum abdominal pain and hemorrhages, retained placenta, and for speeding up contractions during labor. The most frequently cited plants as well as those for which there was greatest consensus tended to be widespread cultivated or weedy species. Although use of medicinal plants by midwives has decreased as a result of retraining programs by government health centers, midwives' knowledge of medicinal plants may provide an important resource for improving maternal-infant health in Honduras and elsewhere. Suggestions for future ethnobotanical and ethnopharmacological studies on this topic are provided.


Assuntos
Tocologia , Plantas Medicinais , Abortivos , Anticoncepcionais Femininos , Parto Obstétrico/métodos , Uso de Medicamentos , Feminino , Fármacos para a Fertilidade/uso terapêutico , Honduras , Humanos , Recém-Nascido , Entrevistas como Assunto , Medicina Tradicional , Cuidado Pós-Natal/métodos , Período Pós-Parto , Gravidez , Complicações na Gravidez/tratamento farmacológico , População Rural
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