Search results for "Pitfall"
showing 10 items of 11 documents
Anticipating the impact of pitfalls in kinetic biodegradation parameter estimation from substrate depletion curves of organic pollutants
2019
[EN] Accurate and reliable estimation of kinetic parameters of pollutant biodegradation processes is essential for environmental and health risk assessment. Common biodegradation models proposed in the literature, such as the nonlinear Monod equation and its simplified versions (e.g. Michaelis-Menten-like and first-order equations), are problematic in terms of accuracy of kinetic parameters due to the parameter correlation. However, a comparison between these models in terms of accuracy and reliability, related to data imprecision, has not been performed in the literature. This task is necessary, mainly because the model selection cannot be straightforward, as shown in this work. To facilit…
Succession in ant communities (Hymenoptera: Formicidae) in deciduous forest clear-cuts - an Eastern European case study
2017
Clear-cutting, the main method of harvesting in many forests in the world, causes a series of dramatic environmental changes to the forest habitat and removes habitat resources for arboreal and epigeal species. It results in considerable changes in the composition of both plant and animal communities. Ants have many critical roles in the maintenance and functioning of forest ecosystems. Therefore, the response of ants to clear-cutting and the time it takes for an ant community to recover after clear-cutting are important indicators of the effect of this harvesting technique on the forest ecosystem. We investigated ground-dwelling ant communities during secondary succession of deciduous fore…
The arthropod community of boreal Norway spruce forests responds variably to stump harvesting
2016
Forest fuel harvesting increases the need to collect not just logging residues but also tree stumps from harvested stands. This biomass removal has raised concern over forest biodiversity. Here, the effects of stump harvesting on spiders, ants, harvestmen, ground beetles and epiedaphic springtails occupying boreal Norway spruce (Picea abies) forest floor were studied two and five years after harvesting by comparing pitfall trap samples from clear-cut sites with and without subsequent stump harvesting and from unharvested mature forests in central Finland. At harvested sites, traps were placed both on intact and exposed mineral soil surface. Open-habitat and generalist ground beetles benefit…
Dades massives i estadística: La perspectiva d'un estadístic
2014
Les dades massives (big data) representen un recurs sense precedents per a afrontar reptes científics, econòmics i socials, però també incrementen la possibilitat de traure conclusions enganyoses. Per exemple, l’ús d’enfocaments basats exclusivament en dades i que es despreocupen de comprendre el fenomen en estudi, que s’orienten a un objectiu esmunyedís i canviant, que no tenen en compte problemes determinants en la recopilació de dades, que resumeixen o «cuinen» inadequadament les dades i que confonen el soroll amb el senyal. Repassarem alguns casos reeixits i il·lustrarem com poden ajudar els principis de l’estadística a obtenir una informació més fiable de les dades. També abordarem els…
Nemastoma bidentatum (Arachnida: Opiliones: Nemastomatidae): neu für Deutschland und die Tschechische Republik
2007
Nemastoma bidentatum (Arachnida: Opiliones: Nemastomatidae): first records for Germany and the Czech Republic. N. bidentatum Roewer, 1914 was found at two places in Germany: first on the island "Harriersand" in the Weser river (Lower Saxony), second on the banks of the river Elbe in the Elbsandsteingebirge (Saxony). Adjacent to the latter locality an occurrence in the Czech Republic could be located close to the German/Czech border in the floodplain of the river Elbe as well. These records are the first for Germany and the Czech Republic. They enlarge the distribution area of N. bidentatum remarkably in both a northern and a western direction. The two populations show conspicuous difference…
Land invertebrates of Columbretes Islands : new species
2020
Este artículo se encuentra disponible en la siguiente URL: https://www.mdpi.com/2071-1050/13/4/1776 La fauna terrestre de invertebrados del archipiélago protegido de Columbretes es poco conocida. Además, los pocos estudios existentes se centran en su isla principal, Illa Grossa. Aquí presentamos el listado de espe-cies de invertebrados no registradas, hasta el momento, en el archipiélago, resultados obtenidos mediante una combinación de capturas con trampas de caída, avistamientos y recolecciones aleatorias realizadas tanto en Illa Grossa como en otros tres islotes de este archipiélago. Mediante el primer método se recolectaron un total de 14.830 especímenes entre 2008-2011. La mayor cantid…
Pharmacogenetics of treatments for pancreatic cancer
2019
Introduction: Despite clinical efforts, pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis. The scarcity of effective therapies can be reflected by the lack of reliable biomarkers to adapt anticancer drugs prescription to tumors’ and patients’ features. Areas covered: Pharmacogenetics should provide the way to select patients who may benefit from a specific therapy that best matches individual and tumor genetic profile, but it has not yet led to gains in outcome. This review describes PDAC pharmacogenetics findings, critically reappraising studies on polymorphisms and -omics profiles correlated to response to gemcitabine, FOLFIRINOX, and nab-paclitaxel combinations, as well as l…
Pitfalls nelle RM whole body con sequenze DWIBS eseguite in pazienti con linfoma.
2016
Obiettivi didattici: Illustrare i principali artefatti ed insidie nella valutazione della Risonanza Magnetica Whole Body (RM-WB) dopo revisione di 331 RM-WB eseguite in pazienti con linfoma. Introduzione: La RM-WB con imaging pesato in diffusione (DWI) è un esame che consente uno studio total body con elevata risoluzione di contrasto, evitando l’esposizione a radiazioni ionizzanti e la somministrazione di mezzo di contrasto [1]. Nel 2004 Takahara ha introdotto una sequenza DWI con tecniche di soppressione del segnale chiamata DWIBS [2]. Questa consente di acquisire rapidamente immagini di multiple aree del corpo sfruttando l’imaging parallelo SENSE che incrementa la risoluzione e riduce gli…
Pitfalls in whole body MRI with diffusion weighted imaging performed on patients with lymphoma: What radiologists should know
2016
The technological advances in radiological imaging and the relevance of a diagnostic tool that may reduce radiation-induced long-term effects have led to a widespread use of whole body magnetic resonance imaging (WB-MRI) with diffusion weighted imaging for oncologic patients. A lot of studies demonstrated the feasibility and reliability of WB-MRI as an alternative technique for lymphoma staging and response assessment during and after treatment. In this paper, taking advantage of our 2years of experience using WB-MRI for lymphoma, we discuss the main pitfalls and artifacts radiologists should know examining a WB-MRI performed on this typology of patients in order to avoid images misinterpre…
Clinical Pitfalls in Diagnosis of Nonmuscle-Invasive Bladder Cancer
2015
Current global economic crisis imposes healthcare system to reduce unnecessary investigations and increase early detection of tumors, to decrease the costs of an advanced disease. Several diagnostic pitfalls may occur dealing with bladder cancer (BC), particularly in nonmuscle-invasive (NMIBC) one. Hematuria, the commonest sign in NMIBC, is often underestimated. Urinary cytology is highly specific for high-grade tumors, but has a low sensitivity for low-grade BC, is operator dependent, and not always obtainable in clinical practice. Numerous urinary tests are available to ameliorate the accuracy of cytology, but none of them is routinly used in urological practice. Ultrasound could hardly …