233 research outputs found

    Effects of abiotic environment on invertebrate herbivory depend on plant community context in a montane grassland

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    Invertebrate herbivores are important and diverse, and their abundance and impacts are expected to undergo unprecedented shifts under climate change. Yet, past studies of invertebrate herbivory have documented a wide variety of responses to changing temperature, making it challenging to predict the direction and magnitude of these shifts. One explanation for these idiosyncratic responses is that changing environmental conditions may drive concurrent changes in plant communities and herbivore traits. Thus, the impacts of changing temperature on herbivory might depend on how temperature combines and interacts with characteristics of plant communities and the herbivores that occupy them. Here, we test this hypothesis by surveying invertebrate herbivory in 220, 0.5 meter-diameter herbaceous plant communities along a 1101-meter elevational gradient. Our results suggest that increasing temperature can drive community-level herbivory via at least three overlapping mechanisms: increasing temperature directly reduced herbivory, indirectly affected herbivory by reducing phylogenetic diversity of the plant community, and indirectly affected herbivory by altering the effects of functional and phylogenetic diversity on herbivory. Consequently, increasing functional diversity of plant communities had a negative effect on herbivory, but only in colder environments while a positive effect of increasing phylogenetic diversity was observed in warmer environments. Moreover, accounting for differences among herbivore feeding guilds considerably improved model fit, because different herbivore feeding guilds varied in their response to temperature and plant community composition. Together, these results highlight the importance of considering both plant and herbivore community context in order to predict how climate change will alter invertebrate herbivory

    Partitioning the effects of plant diversity on ecosystem functions at different trophic levels

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    Biodiversity effects on ecosystem functioning can be partitioned into complementarity effects, driven by many species, and selection effects, driven by few. Selection effects occur through interspecific abundance shifts (dominance) and intraspecific shifts in functioning. Complementarity and selection effects are often calculated for biomass, but very rarely for secondary productivity, i.e. energy transfer to higher trophic levels. We calculated diversity effects for three functions: aboveground biomass, insect herbivory and pathogen infection, the latter two as proxies for energy transfer to higher trophic levels, in a grassland experiment (PaNDiv) manipulating species richness, functional composition, nitrogen enrichment and fungicide treatment. Complementarity effects were on average positive and selection effects negative for biomass production and pathogen infection and multiple species contributed to diversity effects in mixtures. Diversity effects were on average less pronounced for herbivory. Diversity effects for the three functions were not correlated, because different species drove the different effects. Benefits (and costs) from growing in diverse communities, be it reduced herbivore or pathogen damage or increased productivity either due to abundance increases or increased productivity per area were distributed across different plant species, leading to highly variable contributions of single species to effects of diversity on different functions. These results show that different underlying ecological mechanisms can result in similar overall diversity effects across functions.Peer reviewe

    Plant biodiversity promotes sustainable agriculture directly and via belowground effects

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    While the positive relationship between plant biodiversity and ecosystem functioning (BEF) is well established, the extent to which this is mediated via belowground microbial processes is poorly understood. Growing evidence suggests that plant community structure influences soil microbial diversity, which in turn promotes functions desired for sustainable agriculture. Here, we outline the ‘plant-directed’ and soil microbe-mediated mechanisms expected to promote positive BEF. We identify how this knowledge can be utilized in plant diversification schemes to maximize ecosystem functioning in agroecosystems, which are typically species poor and sensitive to biotic and abiotic stressors. In the face of resource overexploitation and global change, bridging the gaps between biodiversity science and agricultural practices is crucial to meet food security in the Anthropocene.Peer reviewe

    A laser-ARPES study of LaNiO3 thin films grown by sputter deposition

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    Thin films of the correlated transition-metal oxide LaNiO3_3 undergo a metal-insulator transition when their thickness is reduced to a few unit cells. Here, we use angle-resolved photoemission spectroscopy to study the evolution of the electronic structure across this transition in a series of epitaxial LaNiO3_3 films of thicknesses ranging from 19 to 2 u.c. grown in situ by RF magnetron sputtering. Our data show a strong reduction of the electronic mean free path as the thickness is reduced below 5 u.c. This prevents the system from becoming electronically two-dimensional, as confirmed by the largely unchanged Fermi surface seen in our experiments. In the insulating state we observe a strong suppression of the coherent quasiparticle peak but no clear gap. These features resemble previous observations of the insulating state of NdNiO3_3.Comment: Submitted to APL Material

    Short communication:Intra- and inter-individual milk microbiota variability in healthy and infected water buffalo udder quarters

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    The concept that ruminant mammary gland quarters are anatomically and physiologically unrelated has been recently challenged by immunological evidence. How this interdependence reflects on individual quarter milk microbiota is unknown. The aim of the present study was to cover this gap by investigating the interdependence of quarters among the same mammary gland at the milk microbiota level using next-generation sequencing of the V4\u201316S rRNA gene. A total of 52 samples were included in this study and classified as healthy or affected by subclinical mastitis. Extraction of DNA, amplification of the V4\u201316S rRNA gene, and sequencing using Ion Torrent Personal Genome Machine (Thermo Fisher Scientific, Waltham, MA) were carried out. We found that the intra-individual variability was lower than the inter-individual one. The present findings further support at milk microbiota level the hypothesis of the interdependence of quarters, as previously demonstrated following immunological studies, suggesting that individual factors (e.g., immunity, genetics) may have a role in modulating milk microbiota

    identifying the most promising agronomic adaptation strategies for the tomato growing systems in southern italy via simulation modeling

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    Abstract The main cultivation area of the Italian processing tomato is the Southern Capitanata plain. Here, the hardest agronomic challenge is the optimization of the irrigation water use, which is often inefficiently performed by farmers, who tend to over-irrigate. This could become unsustainable in the next years, given the negative impacts of climatic changes on groundwater availability and heat stress intensification. The aim of the study was to identify the most promising agronomic strategies to optimize tomato yield and water use in Capitanata, through a modeling study relying on an extensive dataset for model calibration and evaluation (22 data sets in 2005–2018). The TOMGRO simulation model was adapted to open-field growing conditions and was coupled with a soil model to reproduce the impact of water stress on yield and fruit quality. The new model, TomGro_field, was applied on the tomato cultivation area in Capitanata at 5 × 5 km spatial resolution using an ensemble of future climatic scenarios, resulting from the combination of four General Circulation Models, two extreme Representative Concentration Pathways and five 10-years time frames (2030–2070). Our results showed an overall negative impact of climate change on tomato yields (average decrease = 5–10%), which could be reversed by i) the implementation of deficit irrigation strategies based on the restitution of 60–70% of the crop evapotranspiration, ii) the adoption of varieties with longer cycle and iii) the anticipation of 1–2 weeks in transplanting dates. The corresponding irrigation amounts applied are around 360 mm, thus reinforcing that a rational water management could be realized. Our study provides agronomic indications to tomato growers and lays the basis for a bio-economic analysis to support policy makers in charge of promoting the sustainability of the tomato growing systems

    Lattice radiation therapy in clinical practice: a systematic review

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    Purpose: Lattice radiation therapy (LRT) is an innovative type of spatially fractionated radiation therapy. It aims to increase large tumors control probability by administering ablative doses without an increased toxicity. Considering the rising number of positive clinical experiences, the objective of this work is to evaluate LRT safety and efficacy. Method: Reports about LRT clinical experience were identified with a systematic review conducted on four different databases (namely, Medline, Embase, Scopus, and Cochrane Library) through the August 2022. Only LRT clinical reports published in English and with the access to the full manuscript text were considered as eligible. The 2020 update version PRISMA statement was followed. Results: Data extraction was performed from 12 eligible records encompassing 7 case reports, 1 case series, and 4 clinical studies. 81 patients (84 lesions) with a large lesion ranging from 63.2 cc to 3713.5 cc were subjected to exclusive, hybrid, and metabolism guided LRT. Excluding two very severe toxicity with a questionable relation with LRT, available clinical experience seem to confirm LRT safety. When a complete response was not achieved 3-6 months after LRT, a median lesion reduction approximately ≥50 % was registered. Conclusion: This systematic review appear to suggest LRT safety, especially for exclusive LRT. The very low level of evidence and the studies heterogeneity preclude drawing definitive conclusions on LRT efficacy, even though an interesting trend in terms of lesions reduction has been described

    Effect of Pegbovigrastim on Hematological Profile of Simmental Dairy Cows during the Transition Period

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    Pegbovigrastim is a long-acting analog of recombinant bovine granulocyte colony-stimulating factor, that promotes and increases the count and functionality of polymorphonuclear cells in dairy cows. The present study aimed to explore, for the first time in Simmental cows, the clinical and hematological effect of pegbovigrastim during the transition period (TP). Cows were randomly assigned into two groups: treated group (PEG; n = 16) received pegbovigrastim at approximately 7 days before expected parturition and within 6 h after calving, and control group (CTR; n = 16) received saline solution. Blood samples were obtained at −7, 0, 1, 3, 7, 14, 21, and 30 days relative to calving. PEG group showed white blood cells (WBC) count consistently higher compared with CTR group (p < 0.001) until to 3 weeks after calving. Neutrophils remained higher in PEG group (p < 0.001) up to three weeks after calving, compared with CTR group, with slight increment of band cells. Moreover, PEG group displayed a lower index of myeloperoxidase at 1, 3, and 7 days after calving (p < 0.01) compared with CTR. Basophils and lymphocytes showed a similar trend to those observed for neutrophils at 1 day after calving in PEG group. Finally, monocytes remained markedly elevated until 3 days after calving in PEG compared to CTR group (p < 0.001), whereas in PEG group, eosinophils population showed lower percentage values at 1 and 3 days after calving but higher values at 30 days compared with CTR group. PEG group was characterized by lower red blood cells (RBCs) count compared with CTR group (p < 0.05) and higher % of red cell volume distribution width (RDW) from week 2 and mean corpuscular volume (MCV) at 30 days after calving. In addition, the mean platelet volume (MPV) was significantly higher in PEG group at calving, 1, 3, and 7 days after calving compared with CTR group (p < 0.05). For the first time, we described the effect of pegbovigrastim in a breed not specialized exclusively in milk production as Holstein, but with dual purpose (meat and milk), evaluating the complete hematological profile in cows during the transition period. These results provide evidence on the proliferative effect of pegbovigrastim on WBC in Simmental breed highlighting its possible side effect on RBCs

    A yeast strain associated to Anopheles mosquitoes produces a toxin able to kill malaria parasites

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    BACKGROUND: Malaria control strategies are focusing on new approaches, such as the symbiotic control, which consists in the use of microbial symbionts to prevent parasite development in the mosquito gut and to block the transmission of the infection to humans. Several microbes, bacteria and fungi, have been proposed for malaria or other mosquito-borne diseases control strategies. Among these, the yeast Wickerhamomyces anomalus has been recently isolated from the gut of Anopheles mosquitoes, where it releases a natural antimicrobial toxin. Interestingly, many environmental strains of W. anomalus exert a wide anti-bacterial/fungal activity and some of these 'killer' yeasts are already used in industrial applications as food and feed bio-preservation agents. Since a few studies showed that W. anomalus killer strains have antimicrobial effects also against protozoan parasites, the possible anti-plasmodial activity of the yeast was investigated. METHODS: A yeast killer toxin (KT), purified through combined chromatographic techniques from a W. anomalus strain isolated from the malaria vector Anopheles stephensi, was tested as an effector molecule to target the sporogonic stages of the rodent malaria parasite Plasmodium berghei, in vitro. Giemsa staining was used to detect morphological damages in zygotes/ookinetes after treatment with the KT. Furthermore, the possible mechanism of action of the KT was investigated pre-incubating the protein with castanospermine, an inhibitor of β-glucanase activity. RESULTS: A strong anti-plasmodial effect was observed when the P. berghei sporogonic stages were treated with KT, obtaining an inhibition percentage up to around 90 %. Microscopy analysis revealed several ookinete alterations at morphological and structural level, suggesting the direct implication of the KT-enzymatic activity. Moreover, evidences of the reduction of KT activity upon treatment with castanospermine propose a β-glucanase-mediated activity. CONCLUSION: The results showed the in vitro killing efficacy of a protein produced by a mosquito strain of W. anomalus against malaria parasites. Further studies are required to test the KT activity against the sporogonic stages in vivo, nevertheless this work opens new perspectives for the possible use of killer strains in innovative strategies to impede the development of the malaria parasite in mosquito vectors by the means of microbial symbionts
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