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Tree of Heaven (Ailanthus altissima (Mill.) Swingle) is a tree native to China which has invaded disturbed areas in many regions worldwide. Its presence endangers natural ecosystems by displacing native species, modifying habitats, changing community structures, and affecting ecosystem processes. Its invasive nature is enhanced by its high ability to reproduce both vegetatively through root regrowth and sexually through seeds. Seeds, which are wind dispersed, are the main mechanism by which this species reaches new habitats. When they germinate and develop the root system, roots emit new shoots that contribute to a rapid increase in the tree density and the subsequent expansion of the population nearby. The contradictory results about the ecological requirements for seeds to germinate and their degree of dormancy and longevity indicate the complexity and difficulty of understanding the mechanisms that govern the biology and adaptability of this plant. The management of this weed aims at its eradication, with programs based on herbicide applications carried out by injecting the active ingredient directly to the trunk. But, not many active ingredients have shown total control, so new ones should be tested in order to increase the range of available herbicides. During the last few decades, some biological agents have been identified, but their efficacy in controlling the tree and their safety for the local flora have not yet been determined. A correct management strategy should take into account all these aspects in order to contain the expansion of this species and, ultimately, allow its eradication.
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Wheat is a very important crop in Italy, and is infested by wheat bugs belonging to the genera Eurygaster (Hemiptera: Scutellaridae) and Aelia (Hemiptera: Pentatomidae). Many wheat bug infestations have been reported in the north, south, and center of Italy, both in the past as well as recently. The present study was carried out in Sardinia, Italy, during two years (2007 and 2008). The objective of this study was to determine the species and distribution of wheat bugs in durum wheat fields in Sardinia, and to estimate their population density in order to know the incidence of the pest on the island. Sampling took place twice a year (May and June) in three zones, representative of durum wheat cropping in the island. Four species of wheat bugs were found; the predominant species was Eurygaster austriaca (Schrank), followed by Aelia germari (Kuster), Eurygaster maura L., and Aelia acuminata L. The average density of wheat bugs was low (1.1 individuals/m²), but in certain areas it was above the damage threshold (4 individuals/m²). For this reason, the conclusion of the study is that this pest should be monitored in order to control outbreaks and prevent their further spread.
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Hemípteros , Herbivoria , Triticum , Distribución Animal , Animales , Italia , Ninfa , Densidad de PoblaciónRESUMEN
Over the last 30 years, many studies have surveyed weed vegetation on arable land. The 'Arable Weeds and Management in Europe' (AWME) database is a collection of 36 of these surveys and the associated management data. Here, we review the challenges associated with combining disparate datasets and explore some of the opportunities for future research that present themselves thanks to the AWME database. We present three case studies repeating previously published national scale analyses with data from a larger spatial extent. The case studies, originally done in France, Germany and the UK, explore various aspects of weed ecology (community composition, management and environmental effects and within-field distributions) and use a range of statistical techniques (canonical correspondence analysis, redundancy analysis and generalised linear mixed models) to demonstrate the utility and versatility of the AWME database. We demonstrate that (i) the standardisation of abundance data to a common measure, before the analysis of the combined dataset, has little impact on the outcome of the analyses, (ii) the increased extent of environmental or management gradients allows for greater confidence in conclusions and (iii) the main conclusions of analyses done at different spatial scales remain consistent. These case studies demonstrate the utility of a Europe-wide weed survey database, for clarifying or extending results obtained from studies at smaller scales. This Europe-wide data collection offers many more opportunities for analysis that could not be addressed in smaller datasets; including questions about the effects of climate change, macro-ecological and biogeographical issues related to weed diversity as well as the dominance or rarity of specific weeds in Europe.
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The purpose of our article was to describe a simple but effective surgical technique performed on a patient with an extrusion of part of the body of a PAUL drainage implant for glaucoma. We present the case of a patient with refractory glaucoma and a history of multiple ocular interventions. A PAUL shunt was implanted and in the early postoperative period the patient presented extrusion of part of the implant body. An excessive scarring tissue at the lateral rectus muscle tendon hampered the placement of the lateral wing under the muscle; therefore, we decided to trim a part of it and suture the implant body to the sclera. The surgical technique that satisfactorily resolved the complication is described and shown in a video. This is the first time that such complication is described with the PAUL implant. We suggest that the intrinsic characteristics of the implant, mainly the dimensions, material, and thickness, made it possible for a potentially serious complication such as that described to be solved in a relatively simple and nontraumatic way for the eye.
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Arable field margins are valuable habitats providing a wide range of ecosystem services in rural landscapes. Agricultural intensification in recent decades has been a major cause of decline in plant diversity in these habitats. However, the concomitant effects on plant functional diversity are less documented, particularly in Mediterranean areas. In this paper, we analyzed the effect of margin width and surrounding landscape (cover and diversity of land use and field size), used as proxies for management intensity at local and landscape scales, on plant species richness, functional diversity and functional trait values in margins of winter cereal fields in southern Spain. Five functional traits were selected: life form, growth form, seed mass, seed dispersal mode and pollination type. RLQ and fourth-corner analyses were used to link functional traits and landscape variables. A total of 306 plant species were recorded. Species richness and functional diversity were positively related to margin width but showed no response to landscape variables. Functional trait values were affected neither by the local nor landscape variables. Our results suggest that increasing the margin width of conventionally managed cereal fields would enhance both taxonomic and functional diversity of margin plant assemblages, and thus the services they provide to the agro-ecosystem.
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INTRODUCTION: The widespread application of magnetic resonance imaging (MRI) has brought with it an increase in the detection of alterations in the white matter of the central nervous system. AIM. To investigate the evolution of patients with no previous neurological symptoms, but in whom MRI findings are highly suggestive of multiple sclerosis (MS). PATIENTS AND METHODS: We conducted a descriptive study of 11 patients with MRI findings suggesting MS. A longitudinal follow-up was used to determine the radiological progression and conversion into an isolated neurological syndrome and clinically defined MS. RESULTS: Eleven patients (seven females and four males) were identified, with a mean age of 36 years (range: 28-48 years), who had been submitted to an MRI scan due to headache (n = 2), radiculalgia (n = 3), traumatic brain injury (n = 1), syncope (n = 1), peripheral nervous pathology (n = 1) and epileptic seizures (n = 1). The mean number of Barkhof-Tintore criteria in the initial MRI scan was three. The oligoclonal band study was positive in six cases and in nine patients visual evoked potentials were performed (three pathological). The mean follow-up time was 2.9 years (range: 2 months-11.9 years). The mean amount of time elapsed between the first and the second MRI scan was 2.03 years. A radiological progression was identified in seven cases (five of them with gadolinium uptake). Five patients became cases of isolated neurological syndrome, with a mean amount of time since the initial MRI scan of 4.13 years. Of these, three patients presented conversion into clinically defined MS, two into the relapsing-remitting form (after an average of 8.54 years since the initial MRI scan) and another into the primary progressive form. CONCLUSIONS: The identification of incidental lesions that are highly suggestive of MS could help to constitute a group of subjects with an increased risk of developing MS.