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1.
Nutr Health ; : 2601060221109985, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36789753

RESUMO

BACKGROUND: The use of fruits and vegetables for the management and treatment of erectile dysfunction has gained popularity due to the cheaper cost, accessibility and perceived absence of side effects. Much of the work done on plant-based aphrodisiacs has focused on the phytochemistry of secondary metabolites. AIM: This work sought to analyze selected fruits and vegetables that are commonly used in the management of erectile dysfunction in Ghana and quantify the levels of some micro- and macro-elements necessary for good penile health in order to determine the usefulness or otherwise of the selected produce. METHODS: Energy-dispersive X-ray fluorescence spectroscopy was used to detect and quantify the levels of potassium (K), calcium (Ca), selenium (Se), magnesium (Mg), iron (Fe), and zinc (Zn) in carrot roots, cucumber fruit, garlic bulb, ginger rhizome, nutmeg fruit, sweet potato tuber, tiger nut tuber and watermelon fruit. RESULTS: The analysis revealed the presence of K, Ca, Mg, Fe and Zn. Levels of Se were below detection. The concentration of K was the highest in each of the food substances. However, in terms of recommended daily allowance, Mg had the highest contribution. Cucumber fruit and the rind of watermelon fruit had the highest levels of micro- and macro-elements implicated in erectile dysfunction. CONCLUSION: The potential use of these foods to treat and manage erectile dysfunction may not only be due to the presence of phytochemicals alone but also the presence of significant levels of micro- and macro-elements required for good penile health.

2.
PLoS One ; 15(11): e0242662, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33226991

RESUMO

The disturbance of wildlife by humans is a worldwide phenomenon that contributes to the loss of biodiversity. It can impact animals' behaviour and physiology, and this can lead to changes in species distribution and richness. Wildlife disturbance has mostly been assessed through direct observation. However, advances in bio-logging provide a new range of sensors that may allow measuring disturbance of animals with high precision and remotely, and reducing the effects of human observers. We used tri-axial accelerometers to identify daytime flights of roosting straw-coloured fruit bats (Eidolon helvum), which were used as a proxy for roost disturbance. This bat species roosts on trees in large numbers (often reaching hundreds of thousands of animals), making them highly vulnerable to disturbance. We captured and tagged 46 straw-coloured fruit bats with dataloggers, containing a global positioning system (GPS) and an accelerometer, in five roosts in Ghana, Burkina Faso and Zambia. Daytime roost flights were identified from accelerometer signatures and modelled against our activity in the roosts during the days of trapping, as a predictor of roost disturbance, and natural stressors (solar irradiance, precipitation and wind speed). We found that daytime roost flight probability increased during days of trapping and with increasing solar irradiance (which may reflect the search for shade to prevent overheating). Our results validate the use of accelerometers to measure roost disturbance of straw-coloured fruit bats and suggest that these devices may be very useful in conservation monitoring programs for large fruit bat species.


Assuntos
Migração Animal/fisiologia , Quirópteros/fisiologia , Comportamento de Retorno ao Território Vital/fisiologia , África Subsaariana , Animais , Comportamento Animal , Humanos
3.
Curr Biol ; 29(7): R237-R238, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30939302

RESUMO

Animal-mediated seed dispersal is a pivotal component of functioning forest ecosystems all over the globe. Animals that disperse seeds away from their parental plants increase the seeds' chances of survival by releasing them from competition and specialised predators and so contribute to maintain the biodiversity of forests. Furthermore, seeds dispersed into deforested areas provide the opportunity for reforestation. Forest regeneration especially depends on animals that cover large distances easily and cross forest gaps, in particular large-bodied frugivores or mobile species such as birds and bats [1]. Yet, frugivores have started to disappear from forests everywhere, with potentially dramatic consequences for forest composition, regeneration and overall forest biomass [2,3]. Identifying which species contribute substantially to the dispersal of viable seeds, and how these services are affected by fluctuations in population size, is thus pivotal to the understanding and conservation of forest ecosystems [4].


Assuntos
Biodiversidade , Quirópteros/fisiologia , Conservação dos Recursos Naturais , Ecossistema , Animais , Densidade Demográfica
4.
PLoS One ; 10(10): e0138985, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26465139

RESUMO

BACKGROUND: Straw-coloured fruit bats (Eidolon helvum) migrate over vast distances across the African continent, probably following seasonal bursts of resource availability. This causes enormous fluctuations in population size, which in turn may influence the bats' impact on local ecosystems. We studied the movement ecology of this central-place forager with state-of-the-art GPS/acceleration loggers and concurrently monitored the seasonal fluctuation of the colony in Accra, Ghana. Habitat use on the landscape scale was assessed with remote sensing data as well as ground-truthing of foraging areas. PRINCIPAL FINDINGS: During the wet season population low (~ 4000 individuals), bats foraged locally (3.5-36.7 km) in urban areas with low tree cover. Major food sources during this period were fruits of introduced trees. Foraging distances almost tripled (24.1-87.9 km) during the dry season population peak (~ 150,000 individuals), but this was not compensated for by reduced resting periods. Dry season foraging areas were random with regard to urban footprint and tree cover, and food consisted almost exclusively of nectar and pollen of native trees. CONCLUSIONS AND SIGNIFICANCE: Our study suggests that straw-coloured fruit bats disperse seeds in the range of hundreds of meters up to dozens of kilometres, and pollinate trees for up to 88 km. Straw-coloured fruit bats forage over much larger distances compared to most other Old World fruit bats, thus providing vital ecosystem services across extensive landscapes. We recommend increased efforts aimed at maintaining E. helvum populations throughout Africa since their keystone role in various ecosystems is likely to increase due to the escalating loss of other seed dispersers as well as continued urbanization and habitat fragmentation.


Assuntos
Migração Animal/fisiologia , Quirópteros/fisiologia , Comportamento Alimentar/fisiologia , Voo Animal/fisiologia , Acelerometria , Animais , Dieta , Feminino , Cadeia Alimentar , Frutas , Sistemas de Informação Geográfica , Gana , Humanos , Masculino , Dispersão Vegetal/fisiologia , Tecnologia de Sensoriamento Remoto , Estações do Ano , Árvores , Urbanização
5.
PLoS One ; 9(12): e114154, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25469888

RESUMO

Numerous protected areas (PAs) have been created in Africa to safeguard wildlife and other natural resources. However, significant threats from anthropogenic activities and decline of wildlife populations persist, while conservation efforts in most PAs are still minimal. We assessed the impact level of the most common threats to wildlife within PAs in tropical Africa and the relationship of conservation activities with threat impact level. We collated data on 98 PAs with tropical forest cover from 15 countries across West, Central and East Africa. For this, we assembled information about local threats as well as conservation activities from published and unpublished literature, and questionnaires sent to long-term field workers. We constructed general linear models to test the significance of specific conservation activities in relation to the threat impact level. Subsistence and commercial hunting were identified as the most common direct threats to wildlife and found to be most prevalent in West and Central Africa. Agriculture and logging represented the most common indirect threats, and were most prevalent in West Africa. We found that the long-term presence of conservation activities (such as law enforcement, research and tourism) was associated with lower threat impact levels. Our results highlight deficiencies in the management effectiveness of several PAs across tropical Africa, and conclude that PA management should invest more into conservation activities with long-term duration.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , África , Agricultura , Animais , Animais Selvagens , Ecossistema , Incêndios , Clima Tropical
6.
J Phys Chem B ; 118(47): 13609-20, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25356930

RESUMO

The Materials Genome Approach (MGA) aims to accelerate development of new materials by incorporating computational and data-driven approaches to reduce the cost of identification of optimal structures for a given application. Here, we use the MGA to guide the synthesis of triazolium-based ionic liquids (ILs). Our approach involves an IL property-mapping tool, which merges combinatorial structure enumeration, descriptor-based structure representation and sampling, and property prediction using molecular simulations. The simulated properties such as density, diffusivity, and gas solubility obtained for a selected set of representative ILs were used to build neural network models and map properties for all enumerated species. Herein, a family of ILs based on ca. 200,000 triazolium-based cations paired with the bis(trifluoromethanesulfonyl)amide anion was investigated using our MGA. Fourteen representative ILs spreading the entire range of predicted properties were subsequently synthesized and then characterized confirming the predicted density, diffusivity, and CO2 Henry's Law coefficient. Moreover, the property (CO2, CH4, and N2 solubility) trends associated with exchange of the bis(trifluoromethanesulfonyl)amide anion with one of 32 other anions were explored and quantified.

7.
Phys Chem Chem Phys ; 15(9): 3264-72, 2013 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-23348234

RESUMO

Ionic liquids are an emerging class of materials with applications in a variety of fields. Steady progress has been made in the creation of ionic liquids tailored to specific applications. However, the understanding of the underlying structure-property relationships has been slower to develop. As a step in the effort to alleviate this deficiency, the influence of side groups on ionic liquid properties has been studied through an integrated approach utilizing synthesis, experimental determination of properties, and simulation techniques. To achieve this goal, a classical force field in the framework of OPLS/Amber force fields has been developed to predict ionic liquid properties accurately. Cu(I)-catalyzed click chemistry was employed to synthesize triazolium-based ionic liquids with diverse side groups. Values of densities were predicted within 3% of experimental values, whereas self-diffusion coefficients were underestimated by about an order of magnitude though the trends were in excellent agreement, the activation energy calculated in simulation correlates well with experimental values. The predicted Henry coefficient for CO(2) solubility reproduced the experimentally observed trends. This study highlights the importance of integrating experimental and computational approaches in property prediction and materials development, which is not only useful in the development of ionic liquids for CO(2) capture but has application in many technological fields.

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