169,750 research outputs found
Remotely-sensed phenology of Italian forests. Going beyond the species
Remotely sensed observations of seasonal greenness dynamics represent a valuable tool for studying vegetation phenology at regional and ecosystem-level scales. We investigated the seasonal variability of forests in Italy, examining the different mechanisms of phenological response to biophysical drivers. For each point of the Italian National Forests Inventory, we processed a multitemporal profile of the MODIS Enhanced Vegetation Index. Then we applied a multivariate approach for the purpose of (i) classifying the Italian forests into phenological clusters (i.e. pheno-clusters), (ii) identifying the main phenological characteristics and the forest compositions of each pheno-cluster and (iii) exploring the role of climate and physiographic variables in the phenological timing of each cluster. Results identified four pheno-clusters, following a clear elevation gradient and a distinct separation along the Mediterranean-to-temperate climatic transition of Italy. The “High-elevation coniferous” and the “High elevation deciduous” resulted mainly affected by elevation, with the former characterized by low annual productivity and the latter by high seasonality. To the contrary, the “Low elevation deciduous” showed to be mostly associated to moderate climate conditions and a prolonged growing season. Finally, summer drought was the main driving variable for the “Mediterranean evergreen”, characterized by low seasonality. The discrimination of vegetation phenology types can provide valuable information useful as a baseline framework for further studies on forests ecosystem and for management strategies
P0428 Cardiac Sympathetic and Parasympathetic Balance Before and After Gluten Free Diet in Children With Celiac Disease
Celiac disease (CD) is often associated with other autoimmune disorders such as IDDM, autoimmune thyroiditis, rheumatoid arthritis, idiopathic dilated cardiomyopathy. Recently, an increased prevalence of antibodies versus neurons of central and enteric autonomic nervous system has been reported in celiac patients affected by various neurological disorders with improvement of neurological sign in a high percentage of patients after gluten free diet (GFD). We wished to evaluate the cardiac sympathetic and parasympathetic balance (detected with time and frequency analysis of Heart Rate Variability [HRV]) in untreated CD children. Data were compared with healthy subjects and the same patients after GFD. Methods: 10 children with CD (mean age 8.4±3.9 years) were studied at diagnosis and after six months of GFD. The control group consisted of 10 healthy age, sex and weight matched children. Standard 12-lead electrocardiograms (ECG) and ECG monitoring in two leads for HRV evaluation were performed in all patients at diagnosis and after six months of GFD, under standardized experimental conditions. The analysis of the normal beat to beat series (612 interval) and the analysis of variability of R-R interval were performed in time and in frequency domain with a commercially available software (Norav System). All recordings were also visually examined and manually revised to verify beat classification. The following indexes were calculated in time domain: R-R mean length SDNN (standard deviation of all normal RR intervals), rMSSD (square root of the mean of the sum of the squares of differences between adjacent intervals), triangular Index. The following indexes were calculated for spectral analysis: low frequency (LF) power (0.04 to 0.15 Hz) in ms2, high frequency (HF) and LF/HF ratio. Ultra low frequency (ULF) and very low frequency (VLF) were not calculated because they reflect circadian and other long-term variations in heart rhythm. Statistics results were analysed by the Student's t Test
Pp Nutritional Therapy Alone With A Polymeric Diet (Modulen) Is More Effective Than Corticosteroids in Inducing Healing of Intestinal Mucosal Lesions in Active Crohn's Disease
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Characterizing the climatic niche of mast seeding in beech: Evidences of trade-offs between vegetation growth and seed production
Masting is a complex mechanism which is mainly driven by a combination of internal plant resources and climatic conditions. While the driving role of climate in masting is being intensively studied, the interplay among climate, seed production, vegetation growth and phenology still needs further investigation. The objectives of this study were to identify the climatic determinants of different levels of seed production and of NDVI-based vegetation growth and phenology in European beech, and to evaluate if exists a trade-off between these two plant processes. To answer these questions, we used a 25-year-long dataset of beech seed production. We exploited the concept of ecological niche assuming that a mast year can be modeled like a species with variable preferences for different resources, which are the underlying annual climatic conditions; we performed an Ecological Niche Factor Analysis (ENFA), a presence-only modeling tool conventionally used in zoology and botany, and used seasonal (spring, summer, autumn) Standardized Precipitation-Evaporation Index (SPEI) observations, considering the current year (y−0), and up to one (y−1) and two (y−2) years before the masting event. For analyzing the role of vegetation growth and phenology, we used seasonal Normalized Difference Vegetation Index (NDVI) values and associated NDVI-based phenological metrics derived from Landsat imagery. Results indicated the driving role of climate for masting, especially in VHSP years. A moist summer and dry spring at y−2 and a dry summer at y−1 represented the main driving climatic conditions for masting; while a moist spring during the observation year represented the key condition for triggering higher intensities of seed production. Summer NDVI at y−0 and y−1 represented the variables discriminating best between masting and non-masting years and resulted as driven by opposite summer climatic conditions than seed production, thus indicating a trade-off between seed production and vegetation phenology. We concluded that reproduction and vegetation growth act as two different climate-dependent plant responses in beech, in a way that certain conditions through the years promote mast seeding and the opposite conditions favor vegetation growth. The understanding of climate-growth-masting relationships represents indispensable knowledge for providing a holistic view of masting mechanisms and developing adaptive forest management strategies in this species
Successful treatment of pyoderma gangrenosum with low concentration topical tacrolimus in a girl with ulcerative colitis in remission
Outcomes associated with fetal hepatobiliary cysts: a systematic review and meta-analysis
To explore the outcome of fetal hepatobiliary cysts
Mitomycin C in highly myopic eyes - Author reply
Ophthalmology. 2005 Feb;112(2):208-18; discussion 219.
Mitomycin C modulation of corneal wound healing after photorefractive keratectomy in highly myopic eyes.
Gambato C, Ghirlando A, Moretto E, Busato F, Midena E.
SourceRefractive Surgery Service and Antimetabolite Therapy Research Unit, Department of Ophthalmology, University of Padova, Padova, Italy.
Abstract
PURPOSE: To evaluate the role of topical mitomycin C in corneal wound healing (CWH) after photorefractive keratectomy (PRK) in highly myopic eyes.
DESIGN: Prospective, double-masked, randomized clinical trial.
PARTICIPANTS: Seventy-two eyes of 36 patients affected by high (>7 diopters) myopia.
METHODS: In each patient, one eye was randomly assigned to PRK with intraoperative topical 0.02% mitomycin C application, and the fellow eye was treated with a placebo. Postoperatively, mitomycin C-treated eyes received artificial tears (3 times daily, tapered in 3 months), whereas the fellow eye was treated with fluorometholone sodium 2% and artificial tears (3 times daily, tapered in 3 months).
MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), contrast sensitivity, manifest refraction, and biomicroscopy. Contrast sensitivity was determined using the Pelli-Robson chart. Corneal confocal microscopy documented CWH.
RESULTS: Mean follow-up was 18 months (range, 12-36). No side effects or toxic effects were documented. At 12-month follow-up examination, UCVAs (logarithm of the minimum angle of resolution) were 0.4+/-0.48 and 0.5+/-0.53 (P = .03) in mitomycin C-treated eyes and corticosteroid-treated eyes, respectively. At 1 year, corneal haze developed in 20% of corticosteroid-treated eyes, versus 0% of mitomycin C-treated eyes. At 12, 24, and 36 months, corneal confocal microscopy showed activated keratocytes and extracellular matrix significantly more evident in untreated eyes (Ps = 0.004, 0.024, and 0.046, respectively).
CONCLUSION: Topical intraoperative application of 0.02% mitomycin C can reduce haze formation in highly myopic eyes undergoing PRK.
Comment in
Ophthalmology. 2006 Feb;113(2):357; author reply 357-8
Response to infliximab is related to disease duration in paediatric Crohn's disease. (I.F.3.529)
Background: Infliximab is an effective therapy in adult patients with refractory and fistulizing Crohn's disease. Experience in children is still limited. Aim: To evaluate the experience in 22 children and adolescents treated with infliximab with refractory and/or fistulizing Crohn's disease, and to compare duration of response in children between early Crohn's disease and late Crohn's disease. Methods: The experience in 22 children and adolescents treated with a total of 73 infusions was evaluated retrospectively. Treatment indication was refractory Crohn's disease in 9/22 patients, fistulizing Crohn's disease in 7/22 patients and both these conditions in 6/22. All patients with refractory Crohn's disease had late Crohn's disease (> 1 year), whereas 6/13 patients with fistulas had early disease (< 1 year). Results: Mean Paediatric Crohn's Disease Activity Index (PCDAI) decreased from 41.2 to 16.2 at 4 weeks (P < 0.01), and to 15.4 at 18 weeks (P < 0.01). Mean PCDAI at 18 weeks in children with early Crohn's disease and late Crohn's disease was 5. 5 and 18.1, respectively (P < 0.05). Complete closure of fistulas was obtained in 5/6 children with early Crohn's disease and in 2/7 children with late Crohn's disease. Immediate adverse reactions were observed in two children. Conclusions: Infliximab is a highly effective treatment in children and adolescents with both severe refractory or fistulizing Crohn's disease. Children with early Crohn's disease have a higher chance of prolonged response to infliximab than children with late Crohn's disease
Dispelling the Myths Behind First-author Citation Counts
We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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