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1.
Proc Biol Sci ; 291(2023): 20232501, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38772421

RESUMO

Promoting urban green spaces is an effective strategy to increase biodiversity in cities. However, our understanding of how local and landscape factors influence trophic interactions in these urban contexts remains limited. Here, we sampled cavity-nesting bees and wasps and their natural enemies within 85 urban gardens in Zurich (Switzerland) to identify factors associated with the diversity and dissimilarity of antagonistic interactions in these communities. The proportions of built-up area and urban green area at small landscape scales (50 m radius), as well as the management intensity, sun exposure, plant richness and proportion of agricultural land at the landscape scale (250 m radius), were key drivers of interaction diversity. This increased interaction diversity resulted not only from the higher richness of host and natural enemy species, but also from species participating in more interactions. Furthermore, dissimilarity in community structure and interactions across gardens (beta-diversity) were primarily influenced by differences in built-up areas and urban green areas at the landscape scale, as well as by management intensity. Our study offers crucial insights for urban planning and conservation strategies, supporting sustainability goals by helping to understand the factors that shape insect communities and their trophic interactions in urban gardens.


Assuntos
Biodiversidade , Jardins , Vespas , Animais , Vespas/fisiologia , Abelhas/fisiologia , Suíça , Cidades , Cadeia Alimentar
2.
ISME J ; 17(12): 2160-2168, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37773438

RESUMO

The soil priming effect (PE), defined as the modification of soil organic matter decomposition by labile carbon (C) inputs, is known to influence C storage in terrestrial ecosystems. However, how chronic nutrient addition, particularly in leguminous and non-leguminous forests, will affect PE through interaction with nutrient (e.g., nitrogen and phosphorus) availability is still unclear. Therefore, we collected soils from leguminous and non-leguminous subtropical plantations across a suite of historical nutrient addition regimes. We added 13C-labeled glucose to investigate how background soil nutrient conditions and microbial communities affect priming and its potential microbial mechanisms. Glucose addition increased soil organic matter decomposition and prompted positive priming in all soils, regardless of dominant overstory tree species or fertilizer treatment. In non-leguminous soil, only combined nitrogen and phosphorus addition led to a higher positive priming than the control. Conversely, soils beneath N-fixing leguminous plants responded positively to P addition alone, as well as to joint NP addition compared to control. Using DNA stable-isotope probing, high-throughput quantitative PCR, enzyme assays and microbial C substrate utilization, we found that positive PE was associated with increased microbial C utilization, accompanied by an increase in microbial community activity, nutrient-related gene abundance, and enzyme activities. Our findings suggest that the balance between soil available N and P effects on the PE,  was dependent on rhizosphere microbial community composition. Furthermore, these findings highlight the roles of the interaction between plants and their symbiotic microbial communities in affecting soil priming and improve our understanding of the potential microbial pathways underlying soil PEs.


Assuntos
Fabaceae , Microbiota , Solo/química , Nitrogênio/análise , Fósforo , Microbiologia do Solo , Florestas , Plantas/metabolismo , Carbono/análise , Glucose/metabolismo
3.
Ecol Appl ; 33(1): e2727, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36054537

RESUMO

Cities are socioecological systems that filter and select species, therefore establishing unique species assemblages and biotic interactions. Urban ecosystems can host richer wild bee communities than highly intensified agricultural areas, specifically in resource-rich urban green spaces such as allotments and family gardens. At the same time, urban beekeeping has boomed in many European cities, raising concerns that the fast addition of a large number of managed bees could deplete the existing floral resources, triggering competition between wild bees and honeybees. Here, we studied the interplay between resource availability and the number of honeybees at local and landscape scales and how this relationship influences wild bee diversity. We collected wild bees and honeybees in a pollination experiment using four standardized plant species with distinct floral morphologies. We performed the experiment in 23 urban gardens in the city of Zurich (Switzerland), distributed along gradients of urban and local management intensity, and measured functional traits related to resource use. At each site, we quantified the feeding niche partitioning (calculated as the average distance in the multidimensional trait space) between the wild bee community and the honeybee population. Using multilevel structural equation models (SEM), we tested direct and indirect effects of resource availability, urban beekeeping, and wild bees on the community feeding niche partitioning. We found an increase in feeding niche partitioning with increasing wild bee species richness. Moreover, feeding niche partitioning tended to increase in experimental sites with lower resource availability at the landscape scale, which had lower abundances of honeybees. However, beekeeping intensity at the local and landscape scales did not directly influence community feeding niche partitioning or wild bee species richness. In addition, wild bee species richness was positively influenced by local resource availability, whereas local honeybee abundance was positively affected by landscape resource availability. Overall, these results suggest that direct competition for resources was not a main driver of the wild bee community. Due to the key role of resource availability in maintaining a diverse bee community, our study encourages cities to monitor floral resources to better manage urban beekeeping and help support urban pollinators.


Assuntos
Agricultura , Ecossistema , Animais , Abelhas , Cidades , Jardins , Polinização
4.
J Control Release ; 347: 476-488, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35577151

RESUMO

Despite success in vaccinating populations against SARS-CoV-2, concerns about immunity duration, continued efficacy against emerging variants, protection from infection and transmission, and worldwide vaccine availability remain. Molecular adjuvants targeting pattern recognition receptors (PRRs) on antigen-presenting cells (APCs) could improve and broaden the efficacy and durability of vaccine responses. Native SARS-CoV-2 infection stimulates various PRRs, including toll-like receptors (TLRs) and retinoic acid-inducible gene I (RIG-I)-like receptors. We hypothesized that targeting PRRs using molecular adjuvants on nanoparticles (NPs) along with a stabilized spike protein antigen could stimulate broad and efficient immune responses. Adjuvants targeting TLR4 (MPLA), TLR7/8 (R848), TLR9 (CpG), and RIG-I (PUUC) delivered on degradable polymer NPs were combined with the S1 subunit of spike protein and assessed in vitro with isogeneic mixed lymphocyte reactions (isoMLRs). For in vivo studies, the adjuvant-NPs were combined with stabilized spike protein or spike-conjugated NPs and assessed using a two-dose intranasal or intramuscular vaccination model in mice. Combination adjuvant-NPs simultaneously targeting TLR and RIG-I receptors (MPLA+PUUC, CpG+PUUC, and R848+PUUC) differentially induced T cell proliferation and increased proinflammatory cytokine secretion by APCs in vitro. When delivered intranasally, MPLA+PUUC NPs enhanced CD4+CD44+ activated memory T cell responses against spike protein in the lungs while MPLA NPs increased anti-spike IgA in the bronchoalveolar (BAL) fluid and IgG in the blood. Following intramuscular delivery, PUUC NPs induced strong humoral immune responses, characterized by increases in anti-spike IgG in the blood and germinal center B cell populations (GL7+ and BCL6+ B cells) in the draining lymph nodes (dLNs). MPLA+PUUC NPs further boosted spike protein-neutralizing antibody titers and T follicular helper cell populations in the dLNs. These results suggest that protein subunit vaccines with particle-delivered molecular adjuvants targeting TLR4 and RIG-I could lead to robust and unique route-specific adaptive immune responses against SARS-CoV-2.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Proteína DEAD-box 58 , Nanopartículas , Receptores Imunológicos , Receptor 4 Toll-Like , Adjuvantes Imunológicos , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Sistemas de Liberação de Medicamentos , Imunidade Humoral , Imunoglobulina G , Camundongos , Nanopartículas/química , Receptores Imunológicos/agonistas , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Receptor 4 Toll-Like/agonistas
5.
bioRxiv ; 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35132413

RESUMO

Despite recent success in vaccinating populations against SARS-CoV-2, concerns about immunity duration, continued efficacy against emerging variants, protection from infection and transmission, and worldwide vaccine availability, remain. Although mRNA, pDNA, and viral-vector based vaccines are being administered, no protein subunit-based SARS-CoV-2 vaccine is approved. Molecular adjuvants targeting pathogen-recognition receptors (PRRs) on antigen-presenting cells (APCs) could improve and broaden the efficacy and durability of vaccine responses. Native SARS-CoV-2 infection stimulate various PRRs, including toll-like receptors (TLRs) and retinoic-acid-inducible gene I-like receptors (RIG-I). We hypothesized that targeting the same PRRs using adjuvants on nanoparticles along with a stabilized spike (S) protein antigen could provide broad and efficient immune responses. Formulations targeting TLR4 (MPLA), TLR7/8 (R848), TLR9 (CpG), and RIG-I (PUUC) delivered on degradable polymer-nanoparticles (NPs) were combined with the S1 subunit of S protein and assessed in vitro with isogeneic mixed lymphocyte reactions (iso-MLRs). For in vivo studies, the adjuvanted nanoparticles were combined with stabilized S protein and assessed using intranasal and intramuscular prime-boost vaccination models in mice. Combination NP-adjuvants targeting both TLR and RIG-I (MPLA+PUUC, CpG+PUUC, or R848+PUUC) differentially increased proinflammatory cytokine secretion (IL-1ß, IL-12p70, IL-27, IFN-ß) by APCs cultured in vitro, and induced differential T cell proliferation. When delivered intranasally, MPLA+PUUC NPs enhanced local CD4+CD44+ activated memory T cell responses while MPLA NPs increased anti-S-protein-specific IgG and IgA in the lung. Following intramuscular delivery, PUUC-carrying NPs induced strong humoral immune responses, characterized by increases in anti-S-protein IgG and neutralizing antibody titers and germinal center B cell populations (GL7+ and BCL6+ B cells). MPLA+PUUC NPs further boosted S-protein-neutralizing antibody titers and T follicular helper cell populations in draining lymph nodes. These results suggest that SARS-CoV-2-mimicking adjuvants and subunit vaccines could lead to robust and unique route-specific adaptive immune responses and may provide additional tools against the pandemic.

6.
Data Brief ; 37: 107243, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34307807

RESUMO

This article summarizes the data of a survey of flowering plants in 80 sites in five European cities and urban agglomerations (Antwerp, Belgium; greater Paris, France; Poznan, Poland; Tartu, Estonia; and Zurich, Switzerland). Sampling sites were selected based on a double orthogonal gradient of size and connectivity and were urban green areas (e.g. parks, cemeteries). To characterize the flowering plants, two sampling methodologies were applied between April and July 2018. First, a floristic inventory of the occurrence of all flowering plants in the five cities. Second, flower counts in sampling plots of standardized size (1 m2) only in Zurich. We sampled 2146 plant species (contained in 824 genera and 137 families) and across the five cities. For each plant species, we provide its origin status (i.e. whether the plants are native from Europe or not) and 11 functional traits potentially important for plant-pollinator interactions. For each study site, we provide the number of species, genera, and families recorded, the Shannon diversity as well as the proportion of exotic species, herbs, shrubs and trees. In addition, we provide information on the patch size, connectivity, and urban intensity, using four remote sensing-based proxies measured at 100- and 800-m radii.

7.
Ecol Evol ; 11(11): 5762-5776, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34141181

RESUMO

Research hypotheses have been a cornerstone of science since before Galileo. Many have argued that hypotheses (1) encourage discovery of mechanisms, and (2) reduce bias-both features that should increase transferability and reproducibility. However, we are entering a new era of big data and highly predictive models where some argue the hypothesis is outmoded. We hypothesized that hypothesis use has declined in ecology and evolution since the 1990s, given the substantial advancement of tools further facilitating descriptive, correlative research. Alternatively, hypothesis use may have become more frequent due to the strong recommendation by some journals and funding agencies that submissions have hypothesis statements. Using a detailed literature analysis (N = 268 articles), we found prevalence of hypotheses in eco-evo research is very low (6.7%-26%) and static from 1990-2015, a pattern mirrored in an extensive literature search (N = 302,558 articles). Our literature review also indicates that neither grant success nor citation rates were related to the inclusion of hypotheses, which may provide disincentive for hypothesis formulation. Here, we review common justifications for avoiding hypotheses and present new arguments based on benefits to the individual researcher. We argue that stating multiple alternative hypotheses increases research clarity and precision, and is more likely to address the mechanisms for observed patterns in nature. Although hypotheses are not always necessary, we expect their continued and increased use will help our fields move toward greater understanding, reproducibility, prediction, and effective conservation of nature.

8.
Sci Rep ; 9(1): 9769, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31278335

RESUMO

Urban gardens are popular green spaces that have the potential to provide essential ecosystem services, support human well-being, and at the same time foster biodiversity in cities. We investigated the impact of gardening activities on five soil functions and the relationship between plant (600 spp.) and soil fauna (earthworms: 18 spp., springtails: 39 spp.) in 85 urban gardens (170 sites) across the city of Zurich (Switzerland). Our results suggest that high plant diversity in gardens had a positive effect on soil fauna and soil multifunctionality, and that garden management intensity decreased plant diversity. Indices of biological activity in soil, such as organic and microbial carbon and bacterial abundance, showed a direct positive effect on soil multifunctionality. Soil moisture and disturbance, driven by watering and tilling, were the driving forces structuring plant and soil fauna communities. Plant indicator values proved useful to assess soil fauna community structure, even in anthropogenic plant assemblages. We conclude that to enhance soil functions, gardeners should increase plant diversity, and lower management intensity. Soil protective management practices, such as applying compost, mulch or avoiding soil tilling, should be included in urban green space planning to improve urban biodiversity and nature's contribution to people.


Assuntos
Planejamento de Cidades , Jardinagem , Jardins , Solo , Ecologia , Ecossistema , Jardinagem/métodos , Humanos , Solo/química , Suíça
9.
Data Brief ; 25: 103982, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31194048

RESUMO

This article summarizes the data of a survey of vascular plants in 85 urban gardens of the city of Zurich, Switzerland. Data was acquired by two sampling methods: (i) a floristic inventory of entire garden lots based on repeated garden visits, including all vegetation periods; and (ii) vegetation relevés on two plots of standardized size (10 m2) per garden during the summer. We identified a total of 1081 taxa and report the origin status, i.e., whether a taxon is considered native or alien to Switzerland. Furthermore, the origin of a plant or garden population was estimated for each taxon and garden: each taxon in each garden was classified as being either cultivated or spontaneously growing. For each garden, the number of all native, cultivated, and spontaneously growing plant species is given, along with additional information, including garden area, garden type and the landscape-scale proportion of impermeable surface within a 500-m radius. The dataset is related to the research note entitled "Research Note: Self-reported habitat heterogeneity predicts plant species richness in urban gardens" [1]. It is also linked to a comprehensive dataset on biotic and abiotic soil data and as well as to a dataset on soil-surface dwelling and flying arthropods [2-6].

10.
J Anim Ecol ; 88(10): 1522-1533, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31233621

RESUMO

With urbanization identified as being one of the key drivers of change in global land use, and the rapid expansion of urban areas world-wide, it is relevant to evaluate how novel ecological conditions in cities shape species functional traits, which are essential for how species interact with their environments and with each other. Despite the many comparative studies on organisms living in urban and non-urban areas, our knowledge on species responses to urban environments remains limited. For one, much of the ecological research has assumed that the environment changes in a linear fashion from the city core to the city edges, whereas in reality the environments within the cities are highly heterogeneous. Furthermore, studies on species responses to these highly variable ecosystems are often based on interspecific mean trait values, which ignore the potential for high levels of intraspecific variation among individuals in key functional traits. The current study investigated intraspecific functional trait differences for four functional traits associated with body size, mobility and resource selection among rural and urban populations of two common bumblebee species, Bombus pascuorum and Bombus lapidarius, in urban centres and adjacent rural areas in Switzerland. We document shifts in functional traits towards smaller individuals and higher multidimensional trait variation in urban populations compared to rural conspecifics of both species. This shows that urban individuals for both species are on average smaller sized but populations are distinctively different from rural population by increasing their trait richness and diversifying their trait combinations. In addition, we found bimodality in tongue length within urban B. pascuorum populations. Our results suggest that urban and rural populations possibly experience differential selection pressures resulting in trait differences across and among populations. We argue that variations in the respective foraging landscapes in cities leads to smaller sized but phenotypically more diverse populations, and drive functional trait divergence.


Assuntos
Ecossistema , População Rural , Animais , Abelhas , Cidades , Humanos , Suíça , Urbanização
11.
Anesth Analg ; 128(6): e93-e96, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31094789

RESUMO

This pilot study investigated the use of virtual reality (VR) in laboring women. Twenty-seven women were observed for equivalent time during unmedicated contractions in the first stage of labor both with and without VR (order balanced and randomized). Numeric rating scale scores were collected after both study conditions. Significant decreases in sensory pain -1.5 (95% CI, -0.8 to -2.2), affective pain -2.5 (95% CI, -1.6 to -3.3), cognitive pain -3.1 (95% CI, -2.4 to -3.8), and anxiety -1.5 (95% CI, -0.8 to -2.3) were observed during VR. Results suggest that VR is a potentially effective technique for improving pain and anxiety during labor.


Assuntos
Analgesia/métodos , Trabalho de Parto , Manejo da Dor/métodos , Medição da Dor/métodos , Terapia de Exposição à Realidade Virtual , Adulto , Estudos Cross-Over , Feminino , Humanos , Dor/psicologia , Percepção da Dor , Projetos Piloto , Gravidez , Estudos Prospectivos , Índice de Gravidade de Doença , Adulto Jovem
12.
Sci Total Environ ; 658: 1614-1629, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30678018

RESUMO

In the face of growing urban densification, green spaces in cities, such as gardens, are increasingly important for biodiversity and ecosystem services. However, the influences of urban green space management on biodiversity and ecosystem functioning (BEF) relationships is poorly understood. We investigated the relationship between soil fauna and litter decomposition in 170 urban garden sites along a gradient of urbanisation intensity in the city of Zurich, CH. We used litter bags of 1 and 4 mm mesh size to evaluate the contribution of soil meso- and macrofauna on litter decomposition. By using multilevel structural equation models (SEM), we investigated direct and indirect environmental effects and management practices on litter decomposition and litter residue quality. We evaluated the role of taxonomic, functional and phylogenetic diversity of soil fauna species on litter decomposition, based on a sample of 120 species (81,007 individuals; 39 collembola, 18 earthworm, 16 isopod, 47 gastropod species). We found highest litter decomposition rates using 4 mm mesh size litter bags, highlighting the importance of soil macrofauna. Urban warming, a proxy for urbanisation intensity, covaried positively, whereas soil disturbances, such as intensive soil and crop management, were negatively correlated with decomposition rates. Interestingly, soil fauna species richness decreased, with the exception of gastropods, and soil fauna abundance increased with urban warming. Our data also show that plant species richness positively affected litter decomposition by increasing soil fauna species richness and microbial activity. A multivariate analysis of organic compounds in litter residues confirmed the importance of soil fauna species richness and garden management on litter decomposition processes. Overall, we showed, that also in intensively managed urban green spaces, such as gardens, biodiversity of plants and soil fauna drives key ecosystem processes. Urban planning strategies that integrate soil protecting management practices may help to maintain important ecosystem services in this heavily used urban environment.


Assuntos
Biomassa , Biota , Jardinagem , Jardins , Invertebrados , Plantas , Animais , Cidades , Conservação dos Recursos Naturais , Solo , Suíça
13.
Evol Appl ; 9(3): 479-88, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26989439

RESUMO

Numerous studies assess the correlation between genetic and species diversities, but the processes underlying the observed patterns have only received limited attention. For instance, varying levels of habitat disturbance across a region may locally reduce both diversities due to extinctions, and increased genetic drift during population bottlenecks and founder events. We investigated the regional distribution of genetic and species diversities of a coastal sand dune plant community along 240 kilometers of coastline with the aim to test for a correlation between the two diversity levels. We further quantify and tease apart the respective contributions of natural and anthropogenic disturbance factors to the observed patterns. We detected significant positive correlation between both variables. We further revealed a negative impact of urbanization: Sites with a high amount of recreational infrastructure within 10 km coastline had significantly lowered genetic and species diversities. On the other hand, a measure of natural habitat disturbance had no effect. This study shows that parallel variation of genetic and species diversities across a region can be traced back to human landscape alteration, provides arguments for a more resolute dune protection, and may help to design priority conservation areas.

17.
Mol Ther ; 10(4): 697-705, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15451454

RESUMO

Adenovirus has been used widely as a gene transfer vector in the laboratory and clinic for the purpose of gene therapy. Conditionally replication-competent oncolytic adenoviruses are capable of multiplying up to a thousand old in target cells, a property that might prove to be of tremendous potential in the area of cancer therapy. Intravesicular therapy of refractory superficial bladder cancer employing an oncolytic adenovirus would allow for local administration and efficient delivery of virus to bladder tumor. The glycosaminoglycan layer on the surface of the bladder urothelium acts as a nonspecific antiadherence barrier and may be a significant roadblock to efficient infection of the urothelium by adenoviruses. Several laboratories have investigated the potential utility of bladder pretreatment with chemical agents to enhance the adenovirus infection of bladder urothelium but with limited success. A class of compounds has been identified that is effective for pretreatment of urothelium, permitting efficient adenoviral infection. In a murine model, pretreatment of the bladder with 0.1% dodecyl-beta-D-maltoside (DDM) or sodium dodecyl sulfate (SDS) for 5 min resulted in >90% transduction of the urothelial layer within 15 min after exposure to a replication-defective adenovirus compared to

Assuntos
Adenoviridae/genética , Técnicas de Transferência de Genes , Vetores Genéticos , Glucosídeos/farmacologia , Dodecilsulfato de Sódio/farmacologia , Bexiga Urinária/citologia , Urotélio/efeitos dos fármacos , Animais , Benzenossulfonatos/farmacologia , Feminino , Vetores Genéticos/genética , Glicosaminoglicanos/metabolismo , Camundongos , Ratos , Bexiga Urinária/virologia , Urotélio/metabolismo , Urotélio/virologia
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