369 research outputs found
Classification and mapping of the woody vegetation of Gonarezhou National Park, Zimbabwe
Within the framework of the Great Limpopo Transfrontier Conservation Area (GLTFCA), the purpose of this study was to produce a classification of the woody vegetation of the Gonarezhou National Park, Zimbabwe, and a map of its potential distribution. Cover-abundance data of woody species were collected in 330 georeferenced relevés across the Park. These data were used to produce two matrices: the first one using the cover-abundance values as collected in five height layers and the second one based on merging the layers into a single cover value for each species. Automatic classifications were produced for both matrices to determine the optimal number of vegetation types. The two classification approaches both produced 14 types belonging to three macro-groups: mopane, miombo and alluvial woodlands. The results of the two classifications were compared looking at the constant, dominant and diagnostic species of each type. The classification based on separate layers was considered more effective and retained. A high-resolution map of the potential distribution of vegetation types for the whole study area was produced using Random Forest. In the model, the relationship between bioclimatic and topographic variables, known to be correlated to vegetation types, and the classified relevés was used. Identified vegetation types were compared with those of other national parks within the GLTFCA, and an evaluation of the main threats and pressures was conducted. Conservation implications: Vegetation classification and mapping are useful tools for multiple purposes including: surveying and monitoring plant and animal populations, communities and their habitats, and development of management and conservation strategies. Filling the knowledge gap for the Gonarezhou National Park provides a basis for standardised and homogeneous vegetation classification and mapping for the entire Great Limpopo Transfrontier Conservation Area
Comparative study of gene expression by cDNA microarray in human colorectal cancer tissues and normal mucosa
The causative molecular pathways underlying the pathogenesis of colorectal cancer (CRC) need to be better characterized. The purpose of our study was to better understand the genetic mechanism of oncogenesis for human colorectal cancer and to identify new potential tumor markers of use in clinical practice. We used cDNA microarrays to compare gene expression profiles of colorectal biopsies from 25 CRC patients and 13 normal mucosa from adjacent non-cancerous tissues. Findings were validated by real-time PCR; in addition, western blotting and immunochemistry analysis were carried out as further confirmation of differential expression at a protein level. Comparing cancerous tissues with normal colonic mucosa we identified 584 known genes differentially expressed to a significant degree (p<0.001). Many of the transcripts that were more abundant in tumors than in non-neoplastic tissues appear to reflect important events for colon carcinogenesis. For example, a significant number of these genes serve as apoptotic inhibitors (e.g. BFAR, BIRC1, BIRC6). Furthermore, we observed the simultaneous up-regulation of HLA-E and the down-regulation of beta2-microglobulin; these genes strongly support a potential tumor escape strategy from immune surveillance in colon cancer tissues. Our study provides new gene candidates in the pathogenesis of human CRC disease. From our results we hypothesize that CRC cells escape immune surveillance through a specific gene expression alteration; moreover, over-expression of several survival genes seems to confer a more anti-apoptotic phenotype. These genes are involved in pathways not previously implicated in CRC pathogenesis and they may provide new targets for therapy.Fil: Bianchini, Michele. Fundación P/la Invest.y Prevención del Cancer. Centro de Investigaciones Oncologicas; ArgentinaFil: Levy, Estrella Mariel. Fundación P/la Invest.y Prevención del Cancer. Centro de Investigaciones Oncologicas; Argentina. Universidad de Buenos Aires; ArgentinaFil: Zucchini, Cinzia. Università di Bologna; ItaliaFil: Pinski, Victor. Universidad de Buenos Aires; ArgentinaFil: Macagno, Carlo. Universidad de Buenos Aires; ArgentinaFil: De Sanctis, Paola. Università di Bologna; ItaliaFil: Valvassori, Luisa. Università di Bologna; ItaliaFil: Carinci, Paolo. Università di Bologna; ItaliaFil: Mordoh, Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentina. Fundación P/la Invest.y Prevención del Cancer. Centro de Investigaciones Oncologicas; Argentin
Understanding Acanthamoeba Keratitis: An In-Depth Review of a Sight-Threatening Eye Infection
Phytosociology and taxonomic notes on some endemic-rich associations of the Naples Gulf
The Gulf of Naples is an important centre of endemism, well known from the floristic point of view, but much less from the phytosociological one. In this paper we investigated the non-forest vegetation focusing on communities rich in endemics. We described two communities as new: Eryngio amethystini-Santolinetum neapolitanae for the garrigues on limestone, Globulario neapolitanae-Loniceretum stabianae for the vegetation on dolomitic rocks, both from the Lattari mountains, and we extend the area of Crithmo maritimi-Limonietum cumani for the vegetation on volcanic rocks and rarely on limestones along the coast, which was known for a few localities. The syntaxonomical position and the phytogeographical context of these communities are discussed. A few taxonomic notes are added on rare or interesting species retrieved in the course of the enquiry
A reserve is not always so good. Change in landscape management after protection negatively affects the floristic diversity of an urban park
The aim of this study is to analyze the floristic changes occurred between 1991 and 2018 in the “Pineto Urban Regional Park” (Rome) as a result of a land-use change that in mid-90s led to the abandonment of traditional pasture practices and a shift to a more intense frequentation for recreational purposes. About 25 years after the change in management the area has a similar floristic richness, but it is characterized by a high turnover rate, a significant homogenization of the flora and a change in the community structure with a higher level of dominance. The removal of the pasture, which has favoured an increasing frequentation by people, seems to be the main driver of these changes. We suggest that a more active management, with the reintroduction of a sustainable grazing and a limitation of the fruition in marginal areas close to the urban matrix, could restore an higher diversity and reverse the homogenization processes detected in this study and at the same time ensure the citizen fruition
Autoinflammatory syndromes: diagnosis and management
During the last decades the description of autoinflammatory syndromes induced great interest among the scientific community. Mainly rheumatologists, immunologists and pediatricians are involved in the discovery of etiopathogenesis of these syndromes and in the recognition of affected patients. In this paper we will discuss the most important clues of monogenic and non-genetic inflammatory syndromes to help pediatricians in the diagnosis and treatment of these diseases
Diabete Tipo 1, Tipo 2 e Tipo X
Il muro concettuale secondo il quale il diabete in età pediatrica ha preferibilmente una patogenesi autoimmune sta ormai definitivamente crollando. Il diabete in età infantile e adolescenziale è molto più eterogeneo dal punto di vista eziopatogenetico di quanto si pensasse. In presenza di una qualsiasi iperglicemia è ormai diventato importantissimo chiedersi la patogenesi di questo sintomo utilizzando tutti gli strumenti che abbiamo oggi a disposizione
Phytosociological overview of the Fagus and Corylus forests in Albania
Aim: The aim of this study is to analyze the mesophilous forests of Albania including Fagus sylvatica and submontane Corylus avellana forests. Mesophilous Albanian forests are poorly known and were not included in the recent syntaxonomic revisions at the European scale. Study area: Albania. Methods: We used a dataset of 284 published and unpublished relevés. They were classified using the Ward's minimum variance. NMDS ordination was conducted, with over-laying of climatic and geological variables, to analyze the ecological gradients along which these forests develop and segregate. Random Forest was used to define the potential distribution of the identified forest groups in Albania. Results: The study identified seven groups of forests in Albania: Corylus avellana forests, Ostrya carpinifolia-Fagus sylvatica forests, lower montane mesophytic Fagus sylvatica forests, middle montane mesophytic Fagus sylvatica forests, middle montane basiphytic Fagus sylvatica forests, upper montane basiphytic Fagus sylvatica forests, upper montane acidophytic Fagus sylvatica forests. These can be grouped into four main types: Corylus avellana and Ostrya carpinifolia-Fagus sylvatica forests, thermo-basiphytic Fagus sylvatica forest, meso-basiphytic Fagus sylvatica forest and acidophytic Fagus sylvatica forests. This scheme corresponds to the ecological classification recently proposed in a European revision for Fagus sylvatica forests Conclusion: Our study supports an ecological classification of mesophilous forests of Albania at the level of suballiance. Analysis is still preliminary at the level of association, but it shows a high diversity of forest types. Taxonomic reference: Euro+Med PlantBase (http://ww2.bgbm.org/EuroPlusMed/) [accessed 25 Novemeber 2019]. Syntaxonomic references: Mucina et al. (2016) for alliances, orders and classes; Willner et al. (2017) for suballiances
Evaluation of Intereye Corneal Asymmetry in Patients with Keratoconus. A Scheimpflug Imaging Study
Purpose: To assess the correlation between keratoconus severity and intereye asymmetry of pachymetric data and posterior elevation values and to evaluate their combined accuracy in discriminating normal corneas from those with keratoconus. Methods: This study included 97 patients: 65 subjects with bilateral normal corneas (NC) and 32 with keratoconus (KC). Central corneal thickness (CCT), thinnest corneal thickness (ThCT) and posterior elevation (PE) at the thinnest point of the cornea were measured in both eyes using Scheimpflug imaging. Intereye asymmetry and its correlation with keratoconus severity were calculated for each variable. The area under the receiver operating characteristic curve (AUROC) was used to compare predictive accuracy of different variables for keratoconus. Results: In normal eyes, intereye differences were significantly lower compared with the keratoconus eyes (p<0.001, for CCT, ThCT and PE). There was a significant exponential correlation between disease severity and intereye asymmetry of steep keratometry (r(2) = 0.55, p<0.001), CCT (r(2) = 0.39, p<0.001), ThCT (r(2) = 0.48, p<0.001) and PE (r(2) = 0.64, p<0.001). After adjustment for keratoconus severity, asymmetry in thinnest pachymetry proved to be the best parameter to characterize intereye corneal asymmetry in keratoconus. This variable had high accuracy and significantly better discriminating ability (AUROC: 0.99) for KC than posterior elevation (AUROC: 0.96), ThCT (AUROC: 0.94) or CCT (AUROC: 0.92) alone. Conclusions: There is an increased intereye asymmetry in keratometry, pachymetry and posterior corneal elevation values in keratoconic patients compared to subjects with normal corneas. Keratoconus patients with more severe disease are also more asymmetric in their disease status which should be taken into account during clinical care
vegetation mapping from high resolution satellite images in the heterogeneous arid environments of socotra island yemen
Socotra Island (Yemen), a global biodiversity hotspot, is characterized by high geo- morphological and biological diversity. In this study, we present a high-resolution vegetation map of the island based on combining vegetation analysis and classification with remote sensing. Two different image classification approaches were tested to assess the most accurate one in mapping the vegetation mosaic of Socotra. Spectral signatures of the vegetation classes were obtained through a Gaussian mixture distribution model, and a sequential maximum a posteriori (SMAP) classification was applied to account for the heterogeneity and the complex spatial pattern of the arid vegetation. This approach was compared to the traditional maximum like- lihood (ML) classification. Satellite data were represented by a RapidEye image with 5 m pixel resolution and five spectral bands. Classified vegetation releves were used to obtain the training and evaluation sets for the main plant communities. Postclassification sorting was performed to adjust the classification through various rule-based operations. Twenty- eight classes were mapped, and SMAP, with an accuracy of 87%, proved to be more effective than ML (accuracy: 66%). The resulting map will represent an important instrument for the elaboration of conservation strategies and the sustainable use of natural resources in the island. © The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original pub- lication, including its DOI. (DOI: 10.1117/1.JRS.7.073527
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