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1.
Int J Biometeorol ; 65(11): 1837-1848, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33990870

RESUMEN

Elevated temperatures negatively affect human reproduction through several processes that regulate nutrient uptake and resource allocation in pregnant women. These can interfere with foetal development, resulting in low birth weight neonates with altered development trajectories. Temperatures that affect the current generation could, therefore, also have an impact on the following generation. We asked whether heat stress affected offspring fertility by asking if current and past ambient temperatures influenced total fertility rates (TFR) in human populations distributed across the world. We analysed time series data in 65 countries using simple regression analyses based on maximum temperatures and temperature amplitudes over 55 years. Supplemental longer time series (up to 100 years) provided information on response patterns in Northern Europe and Greenland's colder climates. There were clear and strong effects of temperatures on the TFR in the concurrent and the previous generation. Our temperature-based models account for 71-95% of the variation in TRF in European countries and Greenland, and 56-99% of the variation in 65 countries worldwide. Our findings are consistent with studies of seasonal variation in fertility and suggest that increased temperatures will negatively influence populations subjected to monthly maximum temperatures above 15-20 °C, while fertility in colder climates benefits from elevated temperatures. Our results provide strong evidence that ambient temperatures have important effects on human fertility, and that these effects persist into the following generation.


Asunto(s)
Tasa de Natalidad , Fertilidad , Europa (Continente) , Femenino , Humanos , Embarazo , Estaciones del Año , Temperatura
2.
Public Health Nutr ; 21(11): 2128-2141, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29611490

RESUMEN

OBJECTIVE: Child undernutrition remains one of the greatest challenges for public health nutrition in rural areas in developing countries. Interventions aiming to increase and conserve agrobiodiversity seem to be promising alternatives to improve child nutrition. However, the existing literature on these interventions is not conclusive about their effectiveness in combating child undernutrition. We tested the hypothesis that 'higher agrobiodiversity is associated with greater dietary diversity and better anthropometric status' in rural Guatemala.Design/Setting/SubjectsIn the summer of 2016, we conducted a cross-sectional study with a sample of 154 children (6-60 months). We conducted dietary recalls and structured interviews, measured children's weight and height, and visited food production systems (Milpas, home gardens, coffee plantations). Crop species richness, nutritional functional diversity, dietary diversity scores and anthropometric status were calculated. RESULTS: Higher food self-sufficiency, nutritional functional diversity and dietary diversity scores were positively correlated with higher crop and animal species richness. Contrarily, remoteness to the local market was negatively correlated with dietary diversity scores. However, higher dietary diversity scores were not correlated with better child anthropometric status. Better child anthropometric status was positively correlated with improved sanitary conditions and maternal education; and negatively correlated with large household size and frequent child morbidity. CONCLUSIONS: Agricultural diversification could diversify diets, increase nutrient availability and improve child anthropometry. However, these interventions need to be accompanied by sanitation improvements, family planning, nutritional education and women's empowerment to strengthen their positive effect on diet and nutrition.


Asunto(s)
Agricultura , Biodiversidad , Dieta/etnología , Abastecimiento de Alimentos/estadística & datos numéricos , Indígenas Centroamericanos/estadística & datos numéricos , Antropometría , Fenómenos Fisiológicos Nutricionales Infantiles , Preescolar , Estudios Transversales , Encuestas sobre Dietas , Femenino , Guatemala , Humanos , Lactante , Masculino , Estado Nutricional , Salud Rural/etnología , Población Rural/estadística & datos numéricos
3.
Ann Hum Biol ; 40(5): 385-95, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23803160

RESUMEN

BACKGROUND: Birth weight (BW) is an important attribute of human populations affecting post-natal mortality and later life morbidity, such as diabetes and reduced cognitive skills. BW is influenced by many factors, whereof temperature regime represents an important factor. METHODS: By applying a generalized linear model, the impact of temperatures, altitude, nutrition, age at motherhood and other potential causes for BW variation were evaluated in more than 60 countries worldwide. National IQ scores were analysed in the same model. RESULTS: This study identified a model explaining 2/3 of the global variation in BW. This model suggests that BW will decrease by 0.44-1.05% per °C increase in temperature under projected climate change. National IQ scores revealed a close relationship between IQ and BW. However, the model of IQ variation did not appear robust when challenged with variables not correlated with BW. CONCLUSION: Climate change will affect BW, but it cannot be assumed that other human attributes such as IQ will change because (i) BW, in mainly being sensitive to intra-uterine conditions in the last quarter of pregnancy, is a poor predictor of intra-uterine conditions as such and (ii) developmental plasticity may require post-natal stimuli to unfold.


Asunto(s)
Peso al Nacer , Cambio Climático , Pruebas de Inteligencia , Adulto , Femenino , Humanos , Modelos Lineales , Embarazo , Temperatura
4.
Sci Rep ; 12(1): 6450, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35440613

RESUMEN

Several Amazonian species of Plukenetia are remarkably rich sources of polyunsaturated fatty acids, in particular α-linolenic acid. The lipid composition of the large-seeded, recently described 'Mountain Sacha Inchi' Plukenetia carolis-vegae is reported here for the first time, and compared with Plukenetia huayllabambana, two cultivars of Plukenetia volubilis, and a newly developed hybrid between P. volubilis and P. carolis-vegae. All species and cultivars had a very high content of polyunsaturated fatty acids, 82.6-86.7% of total fatty acids, and at least 46.6% α-linolenic acid of total fatty acids. The highest content was found in P. carolis-vegae which had 57.4%. The exceptionally high α-linolenic acid content suggests that P. carolis-vegae may be an important plant-derived dietary source of this essential fatty acid and that the species has considerable potential for further domestication and commercialisation of its seeds and seed oil. A TAG analysis was carried out for the two P. volubilis cultivars, in which LLnLn and LnLL were most prevalent, and for P. huayllabambana, in which LLnLn constituted the largest fraction, followed by LnLnLn, indicating that this large-seeded species also has interesting dietary properties.


Asunto(s)
Euphorbiaceae , Ácido alfa-Linolénico , Ácidos Grasos , Ácidos Grasos Insaturados , Aceites de Plantas , Semillas
5.
Foods ; 8(11)2019 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-31652880

RESUMEN

: All over the world, there are species which may be considered as neglected or underutilized despite their nutritious properties. At present, such crops contribute to food security in isolated areas by providing energy and nutrients in a diversified diet. Such genetic heritage-improved by ancient cultures-is under threat of losing biodiversity as well as the traditional knowledge associated with their cultivation and usage. Among these species, the Andean root and tuber crops (ARTCs) constitute a valuable resource which should be preserved and popularized because of their food and functional properties. We studied three ARTC species (mashua, arracacha, and yacon) to provide data on their composition, essential for increasing their use globally. We compared their nutritional values with the values of more widely used crops. Important differences in nutrient composition among ARTC landraces were found. Mineral nutrients showed significant differences among species. Considerable variations in the contents of prebiotics like fructooligosaccharides or functional elements (antioxidants and glucosinolates) were found among species and intraspecific samples. Certainly, these species are important assets to complement human nutrition and to secure supply of functional elements for healthy diets.

6.
Evol Appl ; 10(5): 498-513, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28515782

RESUMEN

Understanding the distribution of crop genetic diversity in relation to environmental factors can give insights into the eco-evolutionary processes involved in plant domestication. Yam beans (Pachyrhizus Rich. ex DC.) are leguminous crops native to South and Central America that are grown for their tuberous roots but are seed-propagated. Using a landscape genetic approach, we examined correlations between environmental factors and phylogeographic patterns of genetic diversity in Pachyrhizus landrace populations. Molecular analyses based on chloroplast DNA sequencing and a new set of nuclear microsatellite markers revealed two distinct lineages, with strong genetic differentiation between Andean landraces (lineage A) and Amazonian landraces (lineage B). The comparison of different evolutionary scenarios for the diversification history of yam beans in the Andes using approximate Bayesian computation suggests that Pachyrhizus ahipa and Pachyrhizus tuberosus share a progenitor-derivative relationship, with environmental factors playing an important role in driving selection for divergent ecotypes. The new molecular data call for a revision of the taxonomy of Pachyrhizus but are congruent with paleoclimatic and archeological evidence, and suggest that selection for determinate growth was part of ecophysiological adaptations associated with the diversification of the P. tuberosus-P. ahipa complex during the Mid-Holocene.

7.
J Ethnobiol Ethnomed ; 11: 52, 2015 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-26077151

RESUMEN

BACKGROUND: Knowledge about wild edible plants (WEPs) has a high direct-use value. Yet, little is known about factors shaping the distribution and transfer of knowledge of WEPs at global level and there is concern that use of and knowledge about WEPs is decreasing. This study aimed to investigate the distribution, transmission and loss of traditional ecological knowledge (TEK) concerning WEPs used by a Mayan community of Guatemala and to enumerate such plants. METHODS: The case study was carried out in a semi-isolated community where part of the population took refuge in the mountains in 1982-1985 with WEPs as the main source of food. Major variables possibly determining knowledge and therefore investigated were socio-demographic characteristics, distance to and abundance of natural resources and main source of knowledge transmission. A reference list of species was prepared with the help of three key informants. Information about the theoretical dimension of knowledge was gathered through free listing and a questionnaire survey, while practical skills were assessed using a plant identification test with photographs. All villagers older than 7 years participated in the research (n = 62 including key informants). RESULTS: A total of 44 WEPs were recorded. Theoretical knowledge was unevenly distributed among the population, and a small group including very few informants (n = 3) mentioned, on average, three times more plants than the rest of the population during the free listing. Practical knowledge was more homogeneously distributed, key informants recognising 23 plants on average and the rest of the population 17. Theoretical and practical knowledge increased with age, the latter decreasing in the late phases of life. Knowledge about WEPs was transmitted through relatives in 76% of the cases, which led to increased knowledge of plants and ability to recognise them. CONCLUSIONS: The WEP survey may serve as a reference point and as a useful compilation of knowledge for the community for their current and future generations. This study shows that the elder and the refugees living in the area for longer time know more than others about WEPs. It also shows the important role of knowledge transmission through relatives to preserve TEK.


Asunto(s)
Etnobotánica/métodos , Conocimientos, Actitudes y Práctica en Salud , Difusión de la Información/métodos , Plantas Comestibles/clasificación , Grupos de Población , Adolescente , Adulto , Altitud , Ecología/métodos , Femenino , Guatemala , Humanos , Masculino , Persona de Mediana Edad , Población Rural , Encuestas y Cuestionarios , Adulto Joven
8.
J Ethnobiol Ethnomed ; 9: 23, 2013 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-23578098

RESUMEN

BACKGROUND: Medicinal plant species contribute significantly to folk medicine in Colombia. However, few local studies have investigated whether species used are introduced or native and whether there is a difference in importance of native and introduced medicinal plant species. The aim of the present study was to describe the use of medicinal plants within two municipalities, Campo Hermoso and Zetaquira, both in the department of Boyacá, Colombia and to assess the importance of native and introduced plants to healers, amateur healers and local people. As local healers including amateur healers have no history of introduced species our working hypotheses (H(1-2)) were that H(1): native and introduced medicinal plant species are of equal importance and H(2): healers and amateur healers do not differentiate in their preferences between native and introduced medicinal plant species. METHODS: Ten villages were included in the study. A combination of quantitative and qualitative methods was used including questionnaires, semi-structured interviews, in- depth interviews, and open talks. Voucher specimens were collected in home gardens and during field walks. For data analysis, we calculated use value indices and Jaccard index and tested for the above hypothesis using Spearman rank-correlation coefficients and Wilcoxon-Mann-Whitney tests. RESULTS: Eighty medicinal plant species were described by locals as the most frequently used. Of these, 78 species were taxonomically identified, distributed within 41 families and 74 genera, which included 35 native species and 43 introduced. The highest valued families were: Asteraceae, Lamiaceae, Apiaceae, Rutaceae and Verbenaceae. The species ranked highest according to their Use Values, in both municipalities, were Mentha suaveolens Ehrh., Ambrosia cumanensis Kunth, and Verbena littoralis Kunth. Introduced species were more important than native ones in Zetaquira, while there was no difference in importance in Campo Hermoso. While healers relied most on the uses of native species, amateur healers were inclined to rely on introduced species. Medicinal plant administration in both municipalities follow the usual pattern: Leaves are used most commonly prepared by decoction or infusion and administrated orally. CONCLUSIONS: The high proportion of introduced plant species used in the local traditional medicines is similar to the results of a number of other ethnobotanical studies and emphasise the need for efforts to record and maintain traditional knowledge on native species.


Asunto(s)
Fitoterapia , Plantas Medicinales , Colombia , Ecosistema , Etnobotánica
9.
Appl Plant Sci ; 1(7)2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25202568

RESUMEN

PREMISE OF THE STUDY: Microsatellite loci were developed for the understudied root crop yam bean (Pachyrhizus spp.) to investigate intraspecific diversity and interspecific relationships within the genus Pachyrhizus. • METHODS AND RESULTS: Seventeen nuclear simple sequence repeat (SSR) markers with perfect di- and trinucleotide repeats were developed from 454 pyrosequencing of SSR-enriched genomic libraries. Loci were characterized in P. ahipa and wild and cultivated populations of four closely related species. All loci successfully cross-amplified and showed high levels of polymorphism, with number of alleles ranging from three to 12 and expected heterozygosity ranging from 0.095 to 0.831 across the genus. • CONCLUSIONS: By enabling rapid assessment of genetic diversity in three native neotropical crops, P. ahipa, P. erosus, and P. tuberosus, and two wild relatives, P. ferrugineus and P. panamensis, these markers will allow exploration of the genetic diversity and evolutionary history of the genus Pachyrhizus.

10.
J Ethnobiol Ethnomed ; 6: 21, 2010 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-20707893

RESUMEN

BACKGROUND: The Asháninka Native Community Bajo Quimiriki, District Pichanaki, Junín, Peru, is located only 4 km from a larger urban area and is dissected by a major road. Therefore the loss of traditional knowledge is a main concern of the local headman and inhabitants. The present study assesses the state of traditional medicinal plant knowledge in the community and compares the local pharmacopoeia with the one from a related ethnic group. METHODS: Fieldwork was conducted between July and September 2007. Data were collected through semi-structured interviews, collection of medicinal plants in the homegardens, forest walks, a walk along the river banks, participant observation, informal conversation, cross check through voucher specimens and a focus group interview with children. RESULTS: Four-hundred and two medicinal plants, mainly herbs, were indicated by the informants. The most important families in terms of taxa were Asteraceae, Araceae, Rubiaceae, Euphorbiaceae, Solanaceae and Piperaceae. Eighty-four percent of the medicinal plants were wild and 63% were collected from the forest. Exotics accounted to only 2% of the medicinal plants. Problems related to the dermal system, digestive system, and cultural belief system represented 57% of all the medicinal applications. Some traditional healers received non-indigenous customers, using their knowledge as a source of income. Age and gender were significantly correlated to medicinal plant knowledge. Children knew the medicinal plants almost exclusively by their Spanish names. Sixteen percent of the medicinal plants found in this community were also reported among the Yanesha of the Pasco Region. CONCLUSIONS: Despite the vicinity to a city, knowledge on medicinal plants and cultural beliefs are still abundant in this Asháninka Native Community and the medicinal plants are still available in the surroundings. Nevertheless, the use of Spanish names for the medicinal plants and the shift of healing practices towards a source of income with mainly non-indigenous customers, are signs of acculturation. Future studies on quantification of the use of medicinal plants, dynamics of transmission of ethno-medicinal knowledge to the young generations and comparison with available pharmacological data on the most promising medicinal plants are suggested.


Asunto(s)
Etnobotánica/estadística & datos numéricos , Medicina Tradicional , Plantas Medicinales , Grupos de Población/estadística & datos numéricos , Factores de Edad , Conocimientos, Actitudes y Práctica en Salud , Humanos , Perú , Plantas Medicinales/clasificación
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