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1.
J Sex Marital Ther ; 50(3): 293-302, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38006227

RESUMO

Parallel to the advent of social media and the easy access to online pornographic content there is a sharp increase in adolescent females expressing gender dysphoria worldwide. This paper argues that treatment of gender dysphoria in female adolescents must include explicit exploration into their use and exchange of pornographic content, as well as possible online or offline contacts with adults. Possible avenues of how pornographic content may increase the shame and fear of becoming a woman include the acquisition of misogynistic sexual scripts based on false assumptions on sexuality including the normalization of the violation of females as pleasurable for them, peer influence among female friendship groups, the susceptibility of our medical systems to "mass hysteria" phenomena, easier access of adults with sexually abusive intentions to youth through social media, sexual abuse and victim blaming on females, as well as the influence of pornography on mentalization capacities. As the influence of pornography on gender dysphoria in girls is understudied, this paper provides questions for qualitative and quantitative research, case studies and history taking. Especially the lack of an adequate other during exposure may aggravate false assumptions on gender roles and gender inequality seen in mainstream pornography. Girls affected by autism might be at higher risk because of their reduced mentalization capacities. Working through experiences associated with pornographic content and sexually abusive experiences may correct false beliefs about gender inequality and therefore might alleviate gender dysphoria.


Assuntos
Transtorno Autístico , Disforia de Gênero , Adulto , Adolescente , Humanos , Feminino , Literatura Erótica , Comportamento Sexual , Sexualidade
2.
New Phytol ; 205(2): 771-85, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25303438

RESUMO

Environmental selection and dispersal limitation are two of the primary processes structuring biotic communities in ecosystems, but little is known about these processes in shaping soil microbial communities during secondary forest succession. We examined the communities of ectomycorrhizal (EM) fungi in young, intermediate and old forests in a Chinese subtropical ecosystem, using 454 pyrosequencing. The EM fungal community consisted of 393 operational taxonomic units (OTUs), belonging to 21 EM fungal lineages, in which three EM fungal lineages and 11 EM fungal OTUs showed significantly biased occurrence among the young, intermediate and old forests. The EM fungal community was structured by environmental selection and dispersal limitation in old forest, but only by environmental selection in young, intermediate, and whole forests. Furthermore, the EM fungal community was affected by different factors in the different forest successional stages, and the importance of these factors in structuring EM fungal community dramatically decreased along the secondary forest succession series. This study suggests that different assembly mechanisms operate on the EM fungal community at different stages in secondary subtropical forest succession.


Assuntos
Florestas , Micorrizas , Árvores/microbiologia , Biodiversidade , China , Ecossistema , Fungos/genética
3.
Harmful Algae ; 58: 74-84, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-28073461

RESUMO

This study looks at two facets of dominant phytoplankton classes during phytoplankton succession. A detailed assessment of this issue is of special interest with regard to realized niches from a theoretical point of view but also for lake management as practical application. A realized niche mirrors the functional adaptability of an organism in a lake-specific constellation of environmental parameters. Therefore, the characterization of realized niches could be a key factor for management of problematic waters. Different strategies exist to control eutrophication and the risk of blooms by harmful algae. During the last decades, many restoration measures were initiated to manage eutrophicated inland lakes. In the past, it has become evident several times that restoration strategies do not necessarily lead to a reduction of biomass of undesirable cyanobacteria but can even promote their development. Due to this uncertainty of success and the high costs for remediation strategies, new prediction tools are required - ideally, based on routine monitoring data. Therefore, we developed a new method to extract potential optimal growth conditions (POGC) as indicators of realized niches for different phytoplankton taxa from existing data to improve existing strategies used in lake remediation and restoration. The analysis presented in this work is based on dominance pattern of different phytoplankton groups relative to environmental variables. Interpretation of these dominance patterns as indicators of POGC showed distinct pattern for several phytoplankton classes for all investigated objects. We identified low nitrogen and phosphate concentrations as favorable condition for cyanobacteria in Lake Auensee and Lake Feldberger Haussee. The reservoir Bleilochtalsperre showed a high N/P-concentration and cyanobacteria dominance was generally very low.


Assuntos
Cianobactérias/fisiologia , Monitoramento Ambiental/métodos , Fitoplâncton/fisiologia , Eutrofização , Lagos/química , Lagos/microbiologia
4.
Ecol Evol ; 5(14): 2890-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26306174

RESUMO

We are witnessing a growing gap separating primary research data from derived data products presented as knowledge in publications. Although journals today more often require the underlying data products used to derive the results as a prerequisite for a publication, the important link to the primary data is lost. However, documenting the postprocessing steps of data linking, the primary data with derived data products has the potential to increase the accuracy and the reproducibility of scientific findings significantly. Here, we introduce the rBEFdata R package as companion to the collaborative data management platform BEFdata. The R package provides programmatic access to features of the platform. It allows to search for data and integrates the search with external thesauri to improve the data discovery. It allows to download and import data and metadata into R for analysis. A batched download is available as well which works along a paper proposal mechanism implemented by BEFdata. This feature of BEFdata allows to group primary data and metadata and streamlines discussions and collaborations revolving around a certain research idea. The upload functionality of the R package in combination with the paper proposal mechanism of the portal allows to attach derived data products and scripts directly from R, thus addressing major aspects of documenting data postprocessing. We present the core features of the rBEFdata R package along an ecological analysis example and further discuss the potential of postprocessing documentation for data, linking primary data with derived data products and knowledge.

5.
PLoS One ; 9(5): e96022, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24879434

RESUMO

Future climates are likely to include extreme events, which in turn have great impacts on ecological systems. In this study, we investigated possible effects that could mitigate stem breakage caused by a rare and extreme ice storm in a Chinese subtropical forest across a gradient of forest diversity. We used Bayesian modeling to correct stem breakage for tree size and variance components analysis to quantify the influence of taxon, leaf and wood functional traits, and stand level properties on the probability of stem breakage. We show that the taxon explained four times more variance in individual stem breakage than did stand level properties; trees with higher specific leaf area (SLA) were less susceptible to breakage. However, a large part of the variation at the taxon scale remained unexplained, implying that unmeasured or undefined traits could be used to predict damage caused by ice storms. When aggregated at the plot level, functional diversity and wood density increased after the ice storm. We suggest that for the adaption of forest management to climate change, much can still be learned from looking at functional traits at the taxon level.


Assuntos
Biodiversidade , Processos Climáticos , Florestas , Gelo , Caules de Planta/anatomia & histologia , Árvores/anatomia & histologia , Clima Tropical , Teorema de Bayes , Gelo/efeitos adversos , Árvores/genética
6.
PLoS One ; 8(2): e49618, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23457440

RESUMO

Throughfall kinetic energy (TKE) plays an important role in soil erosion in forests. We studied TKE as a function of biodiversity, functional diversity as well as structural stand variables in a secondary subtropical broad-leaved forest in the Gutianshan National Nature Reserve (GNNR) in south-east China, a biodiversity hotspot in the northern hemisphere with more than 250 woody species present. Using a mixed model approach we could identify significant effects of all these variables on TKE: TKE increased with rarefied tree species richness and decreased with increasing proportion of needle-leaved species and increasing leaf area index (LAI). Furthermore, for average rainfall amounts TKE was decreasing with tree canopy height whereas for high rainfall amounts this was not the case. The spatial pattern of throughfall was stable across several rain events. The temporal variation of TKE decreased with rainfall intensity and increased with tree diversity. Our results show that more diverse forest stands over the season have to cope with higher cumulative raindrop energy than less diverse stands. However, the kinetic energy (KE) of one single raindrop is less predictable in diverse stands since the variability in KE is higher. This paper is the first to contribute to the understanding of the ecosystem function of soil erosion prevention in diverse subtropical forests.


Assuntos
Biodiversidade , Chuva , Árvores/anatomia & histologia , Árvores/fisiologia , China , Clima , Ecossistema , Chuva/química , Especificidade da Espécie
7.
PLoS One ; 8(9): e75599, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24098704

RESUMO

Numerous studies have reported positive effects of species richness on plant community productivity. Such biodiversity effects are usually quantified by comparing the performance of plant mixtures with reference monocultures. However, several mechanisms, such as the lack of resource complementarity and facilitation or the accumulation of detrimental agents, suggest that monocultures are more likely than mixtures to deteriorate over time. Increasing biodiversity effects over time could therefore result from declining monocultures instead of reflecting increases in the functioning of mixtures. Commonly, the latter is assumed when positive trends in biodiversity effects occur. Here, we analysed the performance of 60 grassland species growing in monocultures and mixtures over 9 years in a biodiversity experiment to clarify whether their temporal biomass dynamics differed and whether a potential decline of monocultures contributed significantly to the positive net biodiversity effect observed. Surprisingly, individual species' populations produced, on average, significantly more biomass per unit area when growing in monoculture than when growing in mixture. Over time, productivity of species decreased at a rate that was, on average, slightly more negative in monocultures than in mixtures. The mean net biodiversity effect across all mixtures was continuously positive and ranged between 64-217 g per m(2). Short-term increases in the mean net biodiversity effect were only partly due to deteriorating monocultures and were strongly affected by particular species gaining dominance in mixtures in the respective years. We conclude that our species performed, on average, comparably in monocultures and mixtures; monoculture populations being slightly more productive than mixture populations but this trend decreased over time. This suggested that negative feedbacks had not yet affected monocultures strongly but could potentially become more evident in the future. Positive biodiversity effects on aboveground productivity were heavily driven by a small, but changing, set of species that behaved differently from the average species.


Assuntos
Biodiversidade , Ecossistema , Poaceae/crescimento & desenvolvimento , Biomassa , Alemanha , Dinâmica Populacional , Especificidade da Espécie
8.
J Ecol ; 98(4): 917-926, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20852667

RESUMO

1.Insect herbivory can strongly affect ecosystem processes, and its relationship with plant diversity is a central topic in biodiversity-functioning research. However, very little is known about this relationship from complex ecosystems dominated by long-lived individuals, such as forests, especially over gradients of high plant diversity.2.We analysed insect herbivory on saplings of 10 tree and shrub species across 27 forest stands differing in age and tree species richness in an extraordinarily diverse subtropical forest ecosystem in China. We tested whether plant species richness significantly influences folivory in these highly diverse forests or whether other factors play a more important role at such high levels of phytodiversity.3.Leaf damage was assessed on 58 297 leaves of 1284 saplings at the end of the rainy season in 2008, together with structural and abiotic stand characteristics.4.Species-specific mean damage of leaf area ranged from 3% to 16%. Herbivory increased with plant species richness even after accounting for potentially confounding effects of stand characteristics, of which stand age-related aspects most clearly covaried with herbivory. Intraspecific density dependence or other abiotic factors did not significantly influence overall herbivory across forest stands.5.Synthesis.The positive herbivory-plant diversity relationship indicates that effects related to hypotheses of resource concentration, according to which a reduction in damage by specialized herbivores might be expected as host plant concentration decreases with increasing plant diversity, do not seem to be major determinants for overall herbivory levels in our phytodiverse subtropical forest ecosystem. We discuss the potential role of host specificity of dominant herbivores, which are often expected to show a high degree of specialization in many (sub)tropical forests. In the forest system we studied, a much higher impact of polyphagous species than traditionally assumed might explain the observed patterns, as these species can profit from a broad dietary mix provided by high plant diversity. Further testing is needed to experimentally verify this assumption.

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