501 research outputs found

    Tolerance of warmer temperatures does not confer resilience to heatwaves in an Alpine herb

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    Climate change is generating both sustained trends in average temperatures and higher frequency and intensity of extreme events. This poses a serious threat to biodiversity, especially in vulnerable environments, like alpine systems. Phenotypic plasticity is considered to be an adaptive mechanism to cope with climate change in situ, yet studies of the plastic responses of alpine plants to high temperature stress are scarce. Future weather extremes will occur against a background of warmer temperatures, but we do not know whether acclimation to warmer average temperatures confers tolerance to extreme heatwaves. Nor do we know whether populations on an elevational gradient differ in their tolerance or plasticity in response to warming and heatwave events. We investigated the responses of a suite of functional traits of an endemic Australian alpine herb, Wahlenbergia ceracea, to combinations of predicted future (warmer) temperatures and (relative) heatwaves. We also tested whether responses differed between high- vs. low-elevation populations. When grown under warmer temperatures, W. ceracea plants showed signs of acclimation by means of higher thermal tolerance (Tcrit, T50, and Tmax). They also invested more in flower production, despite showing a concurrent reduction in photosynthetic efficiency (Fv/Fm) and suppression of seed production. Heatwaves reduced both photosynthetic efficiency and longevity. However, we found no evidence that acclimation to warmer temperatures conferred tolerance of the photosynthetic machinery to heatwaves. Instead, when exposed to heatwaves following warmer growth temperatures, plants had lower photosynthetic efficiency and underwent a severe reduction in seed production. High- and low-elevation populations and families exhibited limited genetic variation in trait means and plasticity in response to temperature. We conclude that W. ceracea shows some capacity to acclimate to warming conditions but there is no evidence that tolerance of warmer temperatures confers any resilience to heatwaves.This research was supported by the Australian Research Council (DP170101681), an International Ph.D. Scholarship to RN and an ARC Future Fellowship FT110100453 to LK. Research grants funded all research related costs (such as renting growth chambers or buying equipment), while the scholarship paid a stipend to RN

    Effects of warming temperatures on germination responses and trade-offs between seed traits in an alpine plant

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    1. Climate warming may affect multiple aspects of plant life history, including important factors such as germination responses and the key trade-off between offspring size and number. As a case study to address these concepts, we used an alpine plant (waxy bluebell, Wahlenbergia ceracea; Campanulaceae) that shows plasticity to warming in seed traits and in which seed dormancy status regulates germination. We chose an alpine species because alpine environments are ecosystems particularly under threat by climate change. 2. We conducted germination assays under cool and warm temperatures using seeds produced by individuals that were grown under historical (cooler) and future (warmer) temperature scenarios. We assessed the presence of a seed size vs number trade-off, and then examined the effects of seed number and size on germination percentage, the fractions of dormant and viable seeds, and germination velocity. Further, we examined whether warming during parental growth and during germination affected these relationships. 3. We found evidence for a seed size vs number trade-off only under historical parental temperatures. Indeed, under future growth temperatures, parental plants produced fewer and smaller seeds and there was no evidence of a trade-off. However, the reductions in both seed traits under warming did not affect germination, despite correlations of seed size and number with germination traits. Warming increased germination, particularly of larger seeds, but overall it resulted in more than fourfold reductions in parental fitness. 4. Synthesis. Our study shows the importance of growth conditions when evaluating the seed size vs number trade-off. Stressful conditions, such as warmer temperatures, can restrain the ability of plants to reach optimal investment in reproduction, masking the trade-off. By analysing responses across the whole life cycle, we show here an overall detrimental effect of warming, highlighting the potential risk of climate change for W. ceracea, and, potentially, for alpine plant communities more widely.Files can be opened using Excel and analysed using R.Funding provided by: Australian Research CouncilCrossref Funder Registry ID: http://dx.doi.org/10.13039/501100000923Award Number: DP170101681Experiments were conducted using the plant species Wahlnebrgia ceracea (waxy bluebells). Two datasets were used in this manuscript. 1) Seed size vs number trade-off: Parental individuals from a total of 30 lines ('Line') were grown in growth chambers for 191 days under temperature conditions of a historical/cooler (1960–1970) or a projected future/warmer (2090–2100) climate ('Parental_Temperature'). The parental individuals were randomly assigned to one of three blocks, which corresponded to positions inside the chambers, and each block was equivalent in all chambers ('Block'). Day and night temperatures during the experiment were changed every 15 days to mimic seasonality, with the maximum day temperatures during the peak of summer being 24°C and 29°C for the historical and future parental temperatures, respectively. After 100 days since the imposition of the temperature treatments (during the peak of the summer), half of the plants were moved for 5 days to new chambers, where the temperature was 5°C above the respective treatments, i.e., 29°C and 34°C ('Heatwave'). After this time, the parental individuals were moved back to their respective historical or future temperature treatments. We collected the seeds throughout the 191 days of parental growth, and we stored them in desiccators for at least 11 weeks. After this time, we calculated seed size ('Seed_Size') as the average mass of three lots of 50 seeds divided by 50. We calculated seed number ('Seed_Number') as the ratio between the cumulative mass of the seeds produced by each parental individual and seed size. The 30 lines of the parental individuals were obtained by crossing plants that originated from seeds that were collected at the same elevation, either high or low elevation ('Elevation') in sites within Kosciuszko National Park, NSW, Australia. Therefore, 14 lines originated from high elevations and 14 lines from low elevations. 2) Germination responses - seed traits correlations: The seeds were harvested from the parental individuals grown under historical/cooler or projected future/warmer temperatures ('Parental_Temperature') (see above) from a subset of 14 lines ('Line'). These seeds were used in germination assays in the glasshouse under cool (25°C) or warm temperatures (30°C) ('Germination_Temperature'). We measured seed size ('Seed_Size') as the average mass of three lots of 50 seeds; then these seeds were sowed in agar dishes (25 seeds per dish, 2 dishes per temperature treatment from each parental individual). Seed number ('Seed_Number') was the same as above. Dishes were left under temperature treatments for 4 weeks to allow germination of the non-dormant fraction of the seeds ('Not_Dormant_Seeds') and germination was checked once per week. Then, all the dishes were moved to a cold room at 4–5°C in the dark for 4 weeks to allow cold stratification. After this time, dishes were moved back to the glasshouse under the same temperature treatments as before to allow germination of the dormant seeds. We considered seeds to be dormant ('Dormant_seeds') if they germinated during or after cold stratification or if they did not germinate at all but were still determined to be viable at the end of the experiment. We considered seed to be viable ('Viable_Seeds') if they germinated ('Germinated_Seeds') as well as the seeds that contained an endosperm but still did not germinate ('Not_Germinated_Seeds'), while we considered empty seeds as non-viable ('Not_Viable_Seeds'). Germinated and not germinated seeds (as above) were used to calculate the germination percentage. We calculated germination velocity ('Germination_Velocity') as the reciprocal of the mean germination time (germination velocity (germination (%) week-1) GV = (G1 + G2 +…+ Gn) / (G1 x T1 + G2 x T2 +…+ Gn x Tn), where Gn is the number of new germinating seeds at each sampling point, and Tn is the time between each sampling point (= one week). The files provided present the datasets in their first sheet and keys with the definitions of each term in the second sheet

    Testing the evolutionary potential of an alpine plant: Phenotypic plasticity in response to growth temperature far outweighs parental environmental effects and other genetic causes of variation

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    Phenotypic plasticity and rapid evolution are fundamental processes by which organisms can maintain their function and fitness in the face of environmental changes. Here we quantified the plasticity and evolutionary potential of an alpine herb Wahlenbergia ceracea. Utilizing its mixed-mating system, we generated outcrossed and self-pollinated families that were grown in either cool or warm environments, and that had parents that had also been grown in either cool or warm environments. We then analysed the contribution of environmental and genetic factors to variation in a range of phenotypic traits including phenology, leaf mass per area, photosynthetic function, thermal tolerance, and reproductive fitness. The strongest effect was that of current growth temperature, indicating strong phenotypic plasticity. All traits except thermal tolerance were plastic, whereby warm-grown plants flowered earlier, grew larger, and produced more reproductive stems compared with cool-grown plants. Flowering onset and biomass were heritable and under selection, with early flowering and larger plants having higher relative fitness. There was little evidence for transgenerational plasticity, maternal effects, or genotype×environment interactions. Inbreeding delayed flowering and reduced reproductive fitness and biomass. Overall, we found that W. ceracea has the capacity to respond rapidly to climate warming via plasticity, and the potential for evolutionary change.</p

    New Variant of the Treatment of Acromion-Clavicular Dislocation With TightRope ® System in a Mini - Open Approach: A Preliminary Clinical Study

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    Background: Many different surgical techniques have been described to stabilize the acromion-clavicular (AC) dislocations. So far many of these procedures are performed only in arthroscopy. Objectives: In this study, we describe a new technique that utilizes the tightrope with a mini-invasive open approach for the acute stabilization of the acromion-clavicular joint (ACJ) dislocation. Patients and Methods: We set an prospective study aimed to verify the efficacy of this new surgical technique. We treated 28 patients with acute ACJ dislocation with ACJ TightRope ® System with dual mini access. We retrospectively reviewed the data of 34 patients treated with arthroscopic technique. They were considered as the control group. Results: At 6 month’s follow-up, all the 28 patients showed a stable joint during clinical examination and obtained an average Constant score of 98.62/100, with a complete recovery of ROM and strength in abduction. The mean operation time was of 33.7 minutes. The mean recovery duration was 102.8 days. No significant difference was found between the experimental and control groups (P > 0.05). Conclusions: Results of this trial suggest the effectiveness of this new mini-invasive surgical technique in producing clinical and functional recovery in patients with ACJ dislocations

    In situ remediation of contaminated marinesediment: an overview

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    Sediment tends to accumulate inorganic and persistent hydrophobic organic contaminants representing one of the main sinks and sources of pollution. Generally, contaminated sediment poses medium- and long-term risks to humans and ecosystem health; dredging activities or natural resuspension phenomena (i.e., strongly adverse weather conditions) can remobilize pollution releasing it into the water column. Thus, ex situ traditional remediation activities (i.e., dredging) can be hazardous compared to in situ techniques that try to keep to a minimum sediment mobilization, unless dredging is compulsory to reach a desired bathymetric level. We reviewed in situ physico-chemical (i.e., active mixing and thin capping, solidification/stabilization, chemical oxidation, dechlorination, electrokinetic separation, and sediment flushing) and bio-assisted treatments, including hybrid solutions (i.e., nanocomposite reactive capping, bioreactive capping, microbial electrochemical technologies). We found that significant gaps still remain into the knowledge about the application of in situ contaminated sediment remediation techniques from the technical and the practical viewpoint. Only activated carbon-based technologies are well developed and currently applied with several available case studies. The environmental implication of in situ remediation technologies was only shortly investigated on a long-term basis after its application, so it is not clear how they can really perform

    PDE-5i Management of Erectile Dysfunction After Rectal Surgery: A Systematic Review Focusing on Treatment Efficacy

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    Erectile dysfunction (ED) is one of the main functional complications of surgical resections of the rectum due to rectal cancers or inflammatory bowel disease (IBD). The present systematic review aimed at revising ED management strategies applied after rectal resections and their efficacy in terms of improvement of the International Index of Erectile Function (IIEF) score. A literature search was conducted on Medline, EMBASE, Scopus, and Cochrane databases by two independent reviewers following the PRISMA guidelines. Randomized and nonrandomized controlled trials (RCTs, NRCTs), case-control studies, and case series evaluating medical or surgical therapies for ED diagnosed after rectal surgery for both benign and malignant pathologies were eligible for inclusion. Out of 1028 articles initially identified, only five met the inclusion criteria: two RCTs comparing oral phosphodiesterase type-5 inhibitor (PDE-5i) versus placebo; one NRCT comparing PDE-5i versus PDE-5i + vacuum erection devices (VEDs) versus control; and two before-after studies on PDE-5i. A total of 253 (82.7%) rectal cancer patients and 53 (17.3%) IBD patients were included. Based on two RCTs, PDE-5i significantly improved IIEF compared to placebo at 3 months (SMD = 1.07; 95% CI [0.65, 1.48]; p &lt;.00001; I2 = 39%). Improved IIEF was also reported with PDE-5i + VED at 12 months. There is a paucity of articles in the literature that specifically assess efficacy of ED treatments after rectal surgery. Many alternative treatment strategies to PDE-5is remain to be investigated. Future studies should implement standardized preoperative, postoperative, and follow-up sexual function assessment in patients undergoing rectal resections

    Endoparasites in a wild boar population (Sus scrofa) from Bahía Samborombón, Buenos Aires, Argentina

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    En Argentina se sabe poco sobre la parasitofauna en cerdos silvestres. Aquí, se describe por primera vez la comunidad parasitaria de una población silvestre de Sus scrofa en el área protegida Bahía Samborombón. Se tomaron muestras de materia fecal y se revisaron las vísceras de 30 individuos. La prevalencia (P) total fue de 90%, registrándose Eimeria sp. (P = 18.5%), Isospora sp. (P = 22%) (Coccidia), Iodamoeba sp. (P = 52%) (Amoebidae), Macracanthorhynchus hirudinaceus (P = 33%) (Acanthocephala), Ascaris suum (P = 22%), Oesophagostomum dentatum (P = 4%), Globocephalus sp. (P = 7.5%), Metastrongylus sp. (P = 7.5%), Hyostrongylus sp. (P = 18.5%) y Trichuris sp. (P = 4%) (Nematoda) en el análisis coprológico y M. hirudinaceus (P = 33%) y A. suum (P = 23%); O. dentatum (P = 3%) y quistes hidatídicos de Echinococcus sp. (P = 20%) (Cestoda, Taeniidae) en la prospección helmintológica. Los valores de asociación del índice de Fager fueron no significativos con excepción del par Isospora sp.-Eimeria sp. El presente estudio muestra que la población de cerdos silvestres de Bahía Samborombón presenta una alta riqueza de especies parásitas, muchas de las cuales revisten importancia zoonótica como Eimeria sp., Isospora sp., Macracanthorhynchus sp., Ascaris sp. y Echinococcus sp.In Argentina little is known about the parasitofauna in wild pigs. This work discloses parasitic species in a wild population of Sus scrofa in the Bahía Samborombón protected area. Fecal samples were taken from 30 individuals and their viscera were prospected. The total prevalence (P) was 90%, with a specific richness of 11. In the coprological analysis were detected: Eimeria sp. (P = 18.5%), Isospora sp. (P = 22%) (Coccidia), Iodamoeba sp. (P = 52%) (Amoebidae), Macracanthorhynchus hirudinaceus (P = 33%) (Acanthocephala), Ascaris suum (P = 22%), Oesophagostomum dentatum (P = 4%), Globocephalus sp. (P = 7.5%), Metastrongylus sp. (P = 7.5%), Hyostrongylus sp. (P = 18.5%), and Trichuris sp. (P = 4%) (Nematoda). In the helminthological prospections were observed juveniles and adults of M. hirudinaceus (P = 33%) and A. suum (P = 23%); O. dentatum (P = 3%) and hydatid cysts of Echinococcus sp. (P = 20%) (Cestoda, Taeniidae). The association values of the Fager index were not significant except for the pair Isospora sp.-Eimeria sp. The present study shows that the population of wild pigs of Samborombón Bay presents a high richness of parasitic species, many of which have zoonotic importance such as Eimeria sp., Isospora sp., Macracanthorhynchus sp., Ascaris sp., and Echinococcus sp.Facultad de Ciencias Naturales y Muse

    Life cycle inventory data for the Italian agri-food sector: background, sources and methodological aspects

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    AbstractPurposeFor the development of any life cycle assessment study, the practitioner frequently integrates primary data collected on-field, with background data taken from various life cycle inventory databases which are part of most commercial LCA software packages. However, such data is often not generally applicable to all product systems since, especially concerning the agri-food sector, available datasets may not be fully representative of the site specificity of the food product under examination. In this context, the present work investigates the background, sources and methodological aspects that characterise the most known commercial databases containing agri-food data, with a focus on four agri-food supply chains (olive oil, wine, wheat products and citrus fruit), which represent an important asset for the Italian food sector.MethodsSpecifically, the paper entails a review of currently available LCI databases and their datasets with a twofold scope: firstly, to understand how agri-food data is modelled in these databases for a coherent and consistent representation of regional scenarios and to verify whether they are also suitable for the Italian context and, secondly, to identify and analyse useful and relevant methodological approaches implemented in the existing LCI databases when regional data are modelled.ResultsBased on the aforementioned review, it is possible to highlight some problems which may arise when developing an LCI pertaining to the four Italian agri-food supply chains, namely:1. The need for specific inventory datasets to tackle the specificities of agri-food product systems.2. The lack of datasets, within the existing DBs, related to the Italian context and to the abovementioned supply chains. In fact, at present, in the currently available LCI DBs, there are very few (or in some cases none) datasets related to Italian wine, olive oil, wheat-based products and citrus fruit. The few available datasets often contain some data related to the Italian context but also approximate data with that of product systems representing other countries.Furthermore, the present study allowed to identify and discuss the main aspects to be used as starting elements for modelling regional data to be included in a future Italian LCI database of the abovementioned four supply chains.ConclusionsThe results of the present study represent a starting point for the collection of data and its organisation, in order to develop an Italian LCI agri-food database with datasets which are representative of the regional specificities of four agri-food supply chains which play an important role in the Italian economy

    Endoparasites in a wild boar population (Sus scrofa) from Bahía Samborombón, Buenos Aires, Argentina

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    En Argentina se sabe poco sobre la parasitofauna en cerdos silvestres. Aquí, se describe por primera vez la comunidad parasitaria de una población silvestre de Sus scrofa en el área protegida Bahía Samborombón. Se tomaron muestras de materia fecal y se revisaron las vísceras de 30 individuos. La prevalencia (P) total fue de 90%, registrándose Eimeria sp. (P = 18.5%), Isospora sp. (P = 22%) (Coccidia), Iodamoeba sp. (P = 52%) (Amoebidae), Macracanthorhynchus hirudinaceus (P = 33%) (Acanthocephala), Ascaris suum (P = 22%), Oesophagostomum dentatum (P = 4%), Globocephalus sp. (P = 7.5%), Metastrongylus sp. (P = 7.5%), Hyostrongylus sp. (P = 18.5%) y Trichuris sp. (P = 4%) (Nematoda) en el análisis coprológico y M. hirudinaceus (P = 33%) y A. suum (P = 23%); O. dentatum (P = 3%) y quistes hidatídicos de Echinococcus sp. (P = 20%) (Cestoda, Taeniidae) en la prospección helmintológica. Los valores de asociación del índice de Fager fueron no significativos con excepción del par Isospora sp.-Eimeria sp. El presente estudio muestra que la población de cerdos silvestres de Bahía Samborombón presenta una alta riqueza de especies parásitas, muchas de las cuales revisten importancia zoonótica como Eimeria sp., Isospora sp., Macracanthorhynchus sp., Ascaris sp. y Echinococcus sp.In Argentina little is known about the parasitofauna in wild pigs. This work discloses parasitic species in a wild population of Sus scrofa in the Bahía Samborombón protected area. Fecal samples were taken from 30 individuals and their viscera were prospected. The total prevalence (P) was 90%, with a specific richness of 11. In the coprological analysis were detected: Eimeria sp. (P = 18.5%), Isospora sp. (P = 22%) (Coccidia), Iodamoeba sp. (P = 52%) (Amoebidae), Macracanthorhynchus hirudinaceus (P = 33%) (Acanthocephala), Ascaris suum (P = 22%), Oesophagostomum dentatum (P = 4%), Globocephalus sp. (P = 7.5%), Metastrongylus sp. (P = 7.5%), Hyostrongylus sp. (P = 18.5%), and Trichuris sp. (P = 4%) (Nematoda). In the helminthological prospections were observed juveniles and adults of M. hirudinaceus (P = 33%) and A. suum (P = 23%); O. dentatum (P = 3%) and hydatid cysts of Echinococcus sp. (P = 20%) (Cestoda, Taeniidae). The association values of the Fager index were not significant except for the pair Isospora sp.-Eimeria sp. The present study shows that the population of wild pigs of Samborombón Bay presents a high richness of parasitic species, many of which have zoonotic importance such as Eimeria sp., Isospora sp., Macracanthorhynchus sp., Ascaris sp., and Echinococcus sp.Fil: Ciocco, Rocio B.. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; ArgentinaFil: Carpinetti, Bruno Nicolás. Universidad Nacional Arturo Jauretche; ArgentinaFil: Rojas, Pablo. Gobierno de la Provincia de Buenos Aires. Organismo Provincial Para El Desarrollo Sostenible; ArgentinaFil: Castresana, Marcela Beatriz. Gobierno de la Provincia de Buenos Aires. Organismo Provincial Para El Desarrollo Sostenible; ArgentinaFil: Notarnicola, Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Puerto Iguazú; Argentin
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