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1.
Rev. biol. trop ; 70(1)dic. 2022.
Article in Spanish | LILACS, SaludCR | ID: biblio-1407244

ABSTRACT

Resumen Introducción: El conocimiento de la riqueza vegetal y la estacionalidad alrededor de los apiarios de Apis mellifera es una herramienta de planificación indispensable para los apicultores. Debe incluir la disponibilidad de recursos, las preferencias alimenticias y el comportamiento de búsqueda de alimento. Dicha información no está disponible para las Yungas argentinas, uno de los ecosistemas forestales más estacionales de América del Sur. Objetivo: Evaluar la disponibilidad de recursos tróficos a través de un calendario de floración y su relación con las cargas de polen de A. mellifera en las Yungas. Métodos: En El Fuerte, Jujuy, recolectamos muestras mensuales de septiembre a marzo (2014-2015 y 2015-2016) utilizando trampas de polen. Utilizamos técnicas estandarizadas para los análisis palinológicos e índices de asociación para el uso de recursos. Las fenofases fueron Inicio de floración, Plena floración y Fin de floración. Resultados: Se identificaron 47 especímenes botánicos a nivel de especie y 9 a nivel de género. En ambos períodos hubo una oferta moderada de flores al inicio de la primavera, representada igualmente por plantas arbustivas y herbáceas, con un pico de floración en noviembre. Posteriormente, hubo una caída en la disponibilidad, con un pico de floración nuevamente al final de la temporada. En cinco especies de plantas hubo una asociación de media a alta entre la especie vegetal disponible y la presencia de ésta en el espectro polínico de la muestra de polen corbicular recolectada (Vachellia aroma, Blepharocalyx salicifolius, Cantinoa sp., Vernonanthura sp. y Zanthoxylum coco). Conclusión: En esta región hay una oferta moderada de flores de plantas arbustivas y herbáceas a principios de la primavera, con un pico de floración en noviembre y al final de la temporada. Solo cinco, de casi 50 especies de plantas, muestran una asociación de disponibilidad y uso por parte de las abejas.


Abstract Introduction: Knowledge of vegetation richness and seasonality around Apis mellifera apiaries is an indispensable planning tool for beekeepers. It must include resource availability, food preferences and foraging behaviour. Such information is unavailable for the Argentinian Yungas, one of the most seasonal forest ecosystems in South America. Objective: To assess the availability of trophic resources through a flowering calendar and its relationship with A. mellifera pollen loads in the Yungas. Methods: In El Fuerte, Jujuy, we collected monthly samples from September to March (2014-2015 and 2015-2016) using pollen traps. We used standardized techniques for palynological analyses, and association indices for resource use. The phenophases were Beginning of flowering, Full flowering, and End of flowering. Results: We identified 47 botanical specimens to species level and 9 only to genus. In both periods there was a moderate supply of flowers at the beginning of spring, represented equally by shrub and herbaceous plants, with peak flowering in November. Subsequently, there was a drop in availability, with peak flowering again at the end of the season. In five plant species, there was a medium to high association between the plant species available and their presence in the pollen spectrum of the corbicular pollen samples collected (Vachellia aroma, Blepharocalyx salicifolius, Cantinoa sp., Vernonanthura sp. And Zanthoxylum coco). Conclusion: In this region, there is a moderate supply of shrub and herbaceous plant flowers at the beginning of spring, with peak flowering in November and at the end of the season. Only five, out of nearly 50 plant species, show an association of availability and use by bees.


Subject(s)
Animals , Bees/classification , Pollination/physiology , Argentina
2.
PLoS One ; 17(11): e0277027, 2022.
Article in English | MEDLINE | ID: mdl-36355747

ABSTRACT

The hydroclimate of South America is characterized by the South American summer monsoon (SASM), a tropical atmospheric circulation that induces a summer precipitation regime, and the Southern Hemisphere Westerlies (SHW), an extratropical atmospheric circulation that induces a winter precipitation regime. Stretched between these two systems is a NW-SE-oriented region dominated by descending air masses, resulting in the South American subtropical dry zone (SASDZ), also known as the arid diagonal. We investigated the Cerro Tuzgle cushion peatland (CTP) located on the Argentine Altiplano, north of the present-day SASDZ. Previous work revealed that the CTP was consistently in the SASM regime during the last 2900 cal yr BP. Here, we extend the CTP record to the middle Holocene covering the last 7200 cal yr BP to gain further knowledge of the Holocene development of the SASM and potential modulations of the SASDZ. The prominent feature of the entire record is a distinct and lasting transition centred around 3100 cal yr BP characterized by declining minerogenic content, increasing organic carbon content, rising stable carbon isotope values of organic matter and cellulose, and increasing stable oxygen isotope values of cellulose. We interpret this specific proxy pattern as a hydroclimatic transition towards less arid conditions at the CTP after 3100 cal yr BP. The transition corresponds with the end of the continuous Holocene strengthening of the SASM between 3500 cal yr BP and 3000 cal yr BP indicated by proxy records from north and east of the CTP. The CTP does not reflect this strengthening of the SASM and rather exhibits a threshold response indicating the effective establishment of the SASM summer precipitation regime at 24°S. This suggests that moisture supply during a more arid middle Holocene was provided by isotopically depleted precipitation, while moisture supply after the transition originated from isotopically enriched SASM summer precipitation. Concurrent hydroclimatic changes in the SHW winter precipitation regime south of the SASDZ are documented in a distinct lake level rise of Laguna Aculeo (33°50´S) around 3200 cal yr BP. These coinciding hydrological changes of the SASM and the SHW precipitation regimes indicate larger scale reorganisations of atmospheric circulation components, potentially connected to major modulations of the SASDZ. Thus, our CTP record sheds light on the middle to late Holocene development of the SASM at its southern limit and corroborates connections between the tropical and extratropical hydroclimate of South America.


Subject(s)
Geologic Sediments , Lakes , Cellulose , Seasons
3.
Sci Total Environ ; 767: 144926, 2021 May 01.
Article in English | MEDLINE | ID: mdl-33636778

ABSTRACT

The Altiplano-Puna Plateau holds several shallow lakes, which are very sensitive to climate changes. This work is focused on a high-altitude lake system called Lagunas de Vilama (LVS), located in a complex climatic transition area with scarcity of continuous and homogeneous instrumental records. The objective of this study is to determine the regional spatial-temporal variability of precipitation and evaluate the seasonal and interannual lake responses. We use a lake-surfaces record derived from Landsat images to investigate links with regional precipitations and different climatic forcings. The results reveal that austral summer and autumn precipitations control the variability of the annual lake-surfaces. Also, we found intra-annual and interannual lags in the lake responses to precipitations, and identified several wet and dry stages. Our results show negative trends in precipitations and lake-surfaces, whose were strengthened by a shift to a warm phase of the Atlantic Multidecadal Oscillation in the 1990s. The El Niño Southern Oscillation, Pacific Decadal Oscillation, and Southern Annular Mode also exert a strong influence in the region. This study demonstrates that the variability of LVS lakes is strongly related to the South American Monsoon System dynamics and large-scale climate forcings from the Pacific and Atlantic Oceans. This work provides novel indices which demonstrated to be good indicators of regional hydro-climatological variability for this region of South America.

4.
Am J Otolaryngol ; 41(4): 102543, 2020.
Article in English | MEDLINE | ID: mdl-32474327

ABSTRACT

PURPOSE: The purpose of this study is to assess the efficacy of ultrasonography in the differentiation of a bilateral and a unilateral WDTC to help physicians decide on performing a total or a partial thyroidectomy. MATERIALS AND METHODS: Retrospective chart review of all patients diagnosed with papillary thyroid carcinoma following a total thyroidectomy or a complete thyroidectomy between January 2013 and December 2015 at the Department of Otorhinolaryngology and Head and Neck Surgery in Soroka University Medical Center in southern Israel. The preoperative ultrasound images of the thyroid were compared to the final pathology in the contralateral lobe. RESULTS: Seventy seven patients (77) were included in this study, There was no correlation between the sonography in the contralateral lobe and the malignancy on that side (p = 0.479). US had a 39% false negative rate and 69% false positive rate. CONCLUSION: The patients with a well-differentiated carcinoma of the thyroid, a benign nodule detected sonographically in the contralateral lobe should not bear a high weight in decision making regarding the extent of surgery.


Subject(s)
Clinical Decision-Making/methods , Thyroid Cancer, Papillary/diagnostic imaging , Thyroid Cancer, Papillary/surgery , Thyroid Neoplasms/diagnostic imaging , Thyroid Neoplasms/surgery , Thyroidectomy/methods , Ultrasonography , Adult , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Retrospective Studies , Thyroid Cancer, Papillary/pathology , Thyroid Neoplasms/pathology
5.
Rev. biol. trop ; 66(4): 1754-1768, oct.-dic. 2018.
Article in Spanish | LILACS | ID: biblio-1003361

ABSTRACT

Resumen La vegetación chaqueña esta condicionada por diversas presiones ambientales que afectan la fisionomía del paisaje. Con el objetivo de reconocer cambios espaciales de la vegetación y distinguir indicadores de disturbios naturales (inundaciones, sequías) y/o antrópicos (incendios, malezas de cultivos y pastoreo), se analizó la composición y distribución de las asociaciones polínicas de sedimentos superficiales sobre un gradiente ambiental al norte de la región chaqueña argentina (23°-27° S & 59°63° W). Se tomaron 35 muestras en un gradiente de 600 km en dirección SE-NO. El análisis se realizó con métodos multivariados y el índice de valor de importancia (IVI). La zonación mostró un reemplazo gradual de biotipos y taxones. En la zona oriental dominó el polen de palmeras (Copernica alba), hierbas (Poaceae) y árboles altos (Schinopsis balansae). Hacia la zona central predominó el polen de árboles bajos (Schinus, Prosopis ruscifolia, Pisonia zapallo), arbustos (Celtis, Castela) y hierbas (Amaranthaceae/Chenopodiaceae, Poaceae). La zona occidental presentó altos contenidos de polen de árboles altos (Schinopsis balansae, Schinopsis lorentzii, Astronium). Se detectaron conjuntos polínicos que permitieron discernir contingencias ambientales, como las inundaciones (Copernicia alba, Juncaginaceae, Cyperaceae) y actividades antrópicas, tales como incendios (Trithrinax, Shinus, Aspidosperma quebracho-blanco), malezas de cultivos (Amaranthaceae/ Chenopodiaceae, Gomphrena, Urticaceae, Ambrosia) y pastoreo (Prosopis ruscifolia, Prosopis kuntzei, Capparicordis, Cerciduim praecox). Los tipos polínicos más importantes fueron: Schinopsis balansae (9 %), Celtis (8.4 %), Poaceae (7.5 %), Schinus (6.9 %), Copernicia alba (3.7 %), entre otros. Se diferenciaron tres asociaciones polínicas que representaron las comunidades de: 1) palmares y sabanas, 2) bosques bajos y matorrales y 3) bosques altos, que se distribuyeron en umbrales de precipitación de 1 100 - 1 000, 1 000 -850 y 850 - 700 mm respectivamente. Los resultados amplían el conocimiento sobre las asociaciones polínicas de la región chaqueña argentina, ofreciendo una buena perspectiva para interpretar la dinámica del paisaje durante el Holoceno en la región.(AU)


Abstract Chaco vegetation is conditioned by several environmental pressures affecting the physiognomy of the landscape. With the aim to recognize the spatial changes of vegetation and distinguish indicators of natural (floods, droughts) and/or anthropogenic disturbances (fires, weeds of crops and grazing), we analyzed the composition and distribution of pollen assemblages of surface sediments along an environmental in the north of Argentine Chaco region (23°-27° S, 59°-63° W). Thirty-five samples were taken into an environmental gradient comprising 600 km length in SE-NW direction. The analyses was performed by multivariate methods and the importance value index (IVI). Zonation showed a gradual replacement of biotypes and taxa. In the Eastern zone, the pollen of palms (Copernica alba), herbs (Poaceae) and high trees (Schinopsis balansae) were dominant. Towards the middle zone, the pollen of low trees (Schinus, Prosopis ruscifolia, Pisonia zapallo), shrubs (Celtis, Castela) and herbs (Amaranthaceae/Chenopodiaceae, Poaceae) were dominant. The western zone recorded the highest content of pollen of high trees (Schinopsis balansae, Schinopsis lorentzii, Astronium). Pollen types were detected that allowed to discern environmental contingencies, such as floods (Copernicia alba, Juncaginaceae, Cyperaceae) and anthropic activities, such as fires (Trithrinax, Shinus, Aspidosperma quebracho-blanco), weeds of crops (Amaranthaceae/Chenopodiaceae, Gomphrena, Urticaceae, Ambrosia) and grazing (Prosopis ruscifolia, Prosopis kuntzei, Capparicordis, Cerciduim praecox). The most important pollen types were: Schinopsis balansae (9 %), Celtis (8.4 %), Poaceae (7.5 %), Schinus (6.9 %), Copernicia alba (3.7 %), among others. Three pollen assemblages were differentiated which represent the follow communities: 1) palms and savannas, 2) low forests and scrublands and 3) high forests, that are distributed in precipitation thresholds corresponding to, 1 100 - 1 000, 1 000 - 850 and 850 - 700 mm respectively. Results expand the knowledge about the pollen assemblages of the Argentine Chaco region, offering a good perspective to interpret the dynamic of the landscape during the Holocene in the region.(AU)


Subject(s)
Environmental Biomarkers , Environment , Pollination , Argentina , Rain Measurement
6.
Rev. biol. trop ; 66(3): 1182-1196, jul.-sep. 2018. tab, graf
Article in Spanish | LILACS, SaludCR | ID: biblio-977376

ABSTRACT

Resumen En el noroeste de Argentina, los bosques subtropicales de las Yungas son de gran importancia por la gran diversidad vegetal. Las abejas melíferas (A. mellifera) utilizan estos recursos para su alimentación y en consecuencia como un servicio ecosistémico a través de la apicultura. La caracterización de la flora polinífera de una región permite conocer la fuente de alimento y definir la importancia de las diferentes especies vegetales para el desarrollo y mantenimiento de las colonias. El objetivo del presente trabajo es identificar la flora polinífera utilizada por A. mellifera en el sector oeste de las Yungas en Jujuy (Argentina) a través de la caracterización de sus cargas corbiculares y analizar las variaciones a lo largo de la primavera y verano de dos periodos productivos consecutivos. Para ello, se analizaron 14 muestras tomadas mensualmente a la largo de los periodos setiembre 2011 a marzo 2012 y setiembre 2012 a marzo de 2013. Las muestras se obtuvieron a través de trampas caza polen en las entradas de las colmenas y tratadas en el laboratorio según las técnicas convencionales de melisopalinología con posterior acetólisis. Se identificaron un total de 46 tipos polínicos pertenecientes a 25 familias botánicas. Las más importantes de acuerdo a los valores de índice de importancia de familia son: Euphorbiaceae (35.54), Fabaceae (26.27), Asteraceae (20.77), Vitaceae (16.14) y Myrtaceae (9.13). Asimismo, los principales recursos poliníferos fueron Eucalyptus, Eupatorium, Mimosa, Parapiptadenia excelsa, Sebastiania, Viguiera, Zanthoxylum, tipo Cissus y representantes de las familias Cactaceae y Euphorbiaceae. Las variaciones del índice de amplitud de nicho trófico evidencian para la zona una selección de recursos florales, donde se destaca la utilización de especies nativas. La información generada en este estudio, aporta al conocimiento del recurso ofrecido por el bosque y las especies que son de importancia para la producción apícola. Además, de contribuir a potenciar la producción y comercialización de este producto a partir de su valor agregado, permitiendo a los apicultores un buen manejo de las colmenas.


Abstract In Northwest Argentina, Yungas subtropical forests are very important because of their huge vegetal diversity. Honeybees (A. mellifera) use these resources to feed and therefore as an ecosystemic service through beekeeping. The characterization of pollen flora of a region allows getting to know the food source and defining the importance of different plant species for colonies development and maintenance. The aim of the present study is to identify the pollen flora used by A. mellifera in the Yungas Western area in Jujuy (Argentina) by means of their pollen loads characterization and to analyze the variations of two consecutive productive periods throughout spring and summer. To do this, 14 samples taken monthly were analyzed over the periods from September 2011 to March 2012 and September 2012 to March 2013. The samples were obtained from pollen traps at the entrances of the hives and were treated in the laboratory under conventional melisopalinology techniques with subsequent acetolysis. A total of 46 pollen types belonging to 25 botanical families were identified. The most important ones according to the family importance index are Euphorbiaceae (35.54), Fabaceae (26.27), Asteraceae (20.77), Vitaceae (16.14), Myrtaceae (9.13). Zanthoxylum, Sebastiania, Mimosa, Euphorbiaceae, Cactaceae, Parapiptadenia excelsa, Eupatorium, Cissus, Eucalyptus y Viguiera were identified as dominant resources. The variations of the breadth Index trophic niche show a floral resources selection for the area, where the use of native species stands out. The information produced in this study contributes to the knowledge of the resource offered by the forest and the species that are important for beekeeping production. Besides, it contributes to enhance the production and marketing of this product from its added value, allowing beekeepers a good management of hives. Rev. Biol. Trop. 66(3): 1182-1196. Epub 2018 September 01.


Subject(s)
Animals , Argentina , Pollen , Bees , Diet , Pollination , Beekeeping , Forestry
7.
J Ethnobiol Ethnomed ; 14(1): 27, 2018 Apr 11.
Article in English | MEDLINE | ID: mdl-29642950

ABSTRACT

BACKGROUND: The order Hymenoptera comprises melliferous insects (bees, wasps and bumblebees); among them, stingless bees comprise a diverse group of eusocial insects present in tropical and subtropical areas. Of a total of approximately 500 species, 400 are found in the Neotropics. On the continent of America, before the introduction of Apis mellifera, these insects represented the main source of honey and wax. In Argentina, ethnobiological investigations had been carried out on this group of insects, principally in the Atlantic Forest and Chaco regions. Out of a total of 33 species, only 14 were recorded for use or breeding. In the Yungas, however, there are no ethnobiological studies analyzing this group of species, although the use of their products is mentioned in different ethnobotanical works. This paper studies the knowledge and uses of melliferous insects by the inhabitants of the village of Baritú and surrounding. METHOD: Information on location, management and duties assigned (e.g., preparation and administration) to deal with bee products like honey, pollen, wax and propolis was obtained through semi-structured interviews. Besides, reference material was collected to identify melliferous insects known and used in the region. RESULTS: Fifteen ethnospecies were identified and grouped locally according to their defensive behavior. The culturally most important species is the stingless bee Plebeia sp. nov.-mansita-, in terms of frequency of citations and diversity of uses, and among those that sting, the honeybee Apis mellifera-extranjera-. Honey, pollen, wax, and propolis of Plebeia sp. nov. had the highest current frequency of use. Honey is used in food (incorporated at pure state, as a complement and in drinks), as nutraceutical food and in medicinal preparations. In addition, it is an important resource for marketing during the warm season, infusions being the main mode of administration. Pollen is used as a supplement for food and alcoholic drinks, wax mainly in candle making, and propolis. CONCLUSION: The data obtained in this study complements the information available in ethnobotanical studies carried out in the region. The present study is the first on melliferous insects in the area. A new species of stingless bee the genus Plebeia was registered, and it was observed that the known distribution of others has increased.


Subject(s)
Bees , Honey , Pollen , Waxes , Animals , Argentina , Ethnobotany , Knowledge
8.
Arch. argent. dermatol ; 41(1): 25-39, Ene.-feb. 1991. ilus, tab
Article in Spanish | LILACS | ID: lil-105675

ABSTRACT

Se presenta una experiencia realizada en las Termas de Copahue (Neuquén, Argentina) con 23 pacientes psoriáticos tratados en el complejo por un promedio de 10 días. A todos los pacientes se les realizó un seguimiento clínico, fotográfico e histológico, antes y después del tratamiento. Creemos que la terapeutica termal dermatológica es una alternativa válida: a) como un complemento del tratamiento farmacológico, b) como una opción frente a reiterados fracasos terapéuticos, c) ante pacientes con contraindicaciones diversas


Subject(s)
Balneology , Psoriasis/therapy , Mineral Waters/analysis , Psoriasis/epidemiology , Psoriasis/pathology , Sulfur/pharmacology , Sulfur/therapeutic use
9.
Arch. argent. dermatol ; 41(1): 25-39, Ene.-feb. 1991. ilus, tab
Article in Spanish | BINACIS | ID: bin-26589

ABSTRACT

Se presenta una experiencia realizada en las Termas de Copahue (Neuquén, Argentina) con 23 pacientes psoriáticos tratados en el complejo por un promedio de 10 días. A todos los pacientes se les realizó un seguimiento clínico, fotográfico e histológico, antes y después del tratamiento. Creemos que la terapeutica termal dermatológica es una alternativa válida: a) como un complemento del tratamiento farmacológico, b) como una opción frente a reiterados fracasos terapéuticos, c) ante pacientes con contraindicaciones diversas


Subject(s)
Balneology , Psoriasis/therapy , Psoriasis/epidemiology , Psoriasis/pathology , Mineral Waters/analysis , Sulfur/therapeutic use , Sulfur/pharmacology
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