2,593 research outputs found
Convergence of a linearly transformed particle method for aggregation equations
We study a linearly transformed particle method for the aggregation equation
with smooth or singular interaction forces. For the smooth interaction forces,
we provide convergence estimates in and norms depending on the
regularity of the initial data. Moreover, we give convergence estimates in
bounded Lipschitz distance for measure valued solutions. For singular
interaction forces, we establish the convergence of the error between the
approximated and exact flows up to the existence time of the solutions in norm
Habitat Variation in Vernal Pool Ecosystems on Both Sides of the Strait of Gibraltar
We studied vernal pool (VP) ecosystems along a latitudinal gradient crossing the Strait of Gibraltar in order to determine its role in the distribution of VP plant communities. We analyzed flora, vegetation, physical–chemical water parameters, and climatic data from two vernal pool areas on both the European (Iberian) and African (Moroccan) sides of the Strait. Despite the minor distance between both territories, the pools clearly differed in species composition and ecology. However, they showed a similar vegetation zonation in growth forms, including isoetid, batrachiid, and helophytic vegetation. The distribution of the plant communities was related to nutrient load, temperature, and precipitation. Water nitrate concentration was higher in Morocco, where VPs are characterized by Isoetes velata subsp. adspersa and Ranunculus saniculifolius communities. Iberian VPs had lower water nitrate content, and were characterized by Isoetes velata subsp. velata and Ranunculus peltatus communities. We think this nutrient difference is likely to be caused by the different land management regime on each side of the Strait, with more intensive agriculture in Morocco. Long-term (historical) and present-day (ecological) processes have been proposed to account for the habitat variation in vernal pool ecosystems on both sides of the Strait of Gibraltar
Chronic Illness-Related Shame: Development of a New Scale and Novel Approach for IBD Patients' Depressive Symptomatology
The aims of the present study were to develop and validate a scale specifically focused on shame feelings derived from chronic illness-related experiences, the Chronic Illness-related Shame Scale (CISS) and to fill a gap in literature and analyse the role of this construct in the association between inflammatory bowel disease (IBD) symptomatology and depressed mood. This study comprised two samples: a sample of 161 IBD patients and a mixed sample of 65 chronic patients that reported medical data and completed self-report measures. The CISS's unidimensional seven-item structure was evaluated through confirmatory factor analyses. These analyses revealed good to excellent global and local adjustments in both samples. Results also showed that the CISS presents excellent internal consistencies and convergent, concurrent and divergent validity, being a valid, short and robust scale. Furthermore, the present study explored through path analyses, the role of CISS and self-judgement in the relationship between IBD symptomatology and depressed mood. Results showed that, although the level of IBD symptomatology directly predicted patients' depressive symptoms, the majority of this effect was mediated by CISS and self-judgement. Possible explanations for these findings are discussed in more detail in the succeeding text. The present study seems to highlight the pertinence of developing IBD patients' self-compassionate abilities to adaptively deal with symptomatology and related shame feelings. It thus may represent an avenue for the development of compassionate-based interventions for IBD patients and for the conduction of future studies exploring the shame phenomenon in other chronic illnesses. Copyright © 2016 John Wiley & Sons, Ltd
Some aspects of the synchronization in coupled maps
Through numerical simulations we analyze the synchronization time and the
Lyapunov dimension of a coupled map lattice consisting of a chain of chaotic
logistic maps exhibiting power law interactions. From the observed behaviors we
find a lower bound for the size of the lattice, independent of the range
and strength of the interaction, which imposes a practical lower bound in
numerical simulations for the system to be considered in the thermodynamic
limit. We also observe the existence of a strong correlation between the
averaged synchronization time and the Lyapunov dimension. This is an
interesting result because it allows an analytical estimation of the
synchronization time, which otherwise requires numerical simulations.Comment: 4 pages, 6 figure
6β-Chloro-5α-hydroxy-20-oxopregnan-3β-yl acetate
The title steroid, C23H35ClO4, is a pregnane derivative prepared by ring opening of the corresponding 5α,6α-epoxy steroid with BiCl3. There are two symmetry-independent molecules in the asymmetric unit that show no significant differences concerning bond lengths and angles. The conformation of the six-membered rings in both molecules is close to a chair form, while the five-membered ring adopts an envelope conformation. All rings in both molecules are trans-fused. The molecules are held together by an extensive O—H⋯O hydrogen-bonding network
Sistema distribuído de monitorização de consumos e de qualidade de energia elétrica
Este artigo descreve a implementação e teste de um
sistema distribuído de medição de grandezas elétricas, concebido
para utilização com cargas tipicamente existentes nas residências,
que possibilita a monitorização remota do consumo e também
possui capacidade de deteção de eventos de qualidade de energia
elétrica. O sistema é operado pelo utilizador a partir de um
computador, através de um programa monitorizador dotado de
interface gráfica, que recebe os dados recolhidos por um
conjunto de nós sensores ligados às cargas que se deseja
monitorizar. A comunicação de dados assenta sobre uma rede de
sensores sem fios desenvolvida com base nos protocolos
IEEE 802.15.4 e ZigBee. Os nós da rede são baseados no circuito
integrado CC2530, da Texas Instruments, que integra um
microcontrolador e um transceiver RF num mesmo chip. A
implementação do sistema envolveu a concepção e
desenvolvimento do hardware dos nós sensores, que efetuam a
medição das grandezas elétricas, do software embebido nos nós
da rede de sensores sem fios, que gere a aquisição e envio dos
dados dos nós sensores até ao computador, e do software
monitorizador no computador. Os resultados obtidos nos testes
realizados excederam as expetativas iniciais, tendo os erros de
medição ficado abaixo do patamar de 1%.Fundação para a Ciência e a Tecnologia (FCT
Development of a metric of aquatic invertebrates for volunteers (MAIV): a simple and friendly biotic metric to assess ecological quality of streams
Citizen science activities, involving local people in volunteer-supported and sustainable
monitoring programs, are common. In this context, the objective of the present work was to develop a
simple Metric of Aquatic Invertebrates for Volunteers (MAIV), including a user-friendly tool that can
be easily accessed by volunteers, and to evaluate the e ciency of a volunteer monitoring program
following an audit procedure. To obtain MAIV values, macroinvertebrate communities were reduced
to 18 surrogate taxa, which represented an acceptable compromise between simplicity, e ciency, and
reproducibility of the data, compared to the regular Water Framework Directive monitoring. When
compared to results obtained with the National Classification System of Portugal, MAIV accurately
detected moderate, poor, and bad ecological status. Thus, MAIV can be used by volunteers as a
complement to the o cial monitoring program, as well as a prospective early warning tool for
local problems related to ecological quality. Volunteers were students supervised by their teachers.
Results obtained by volunteers were compared to results obtained by experts on macroinvertebrate
identification to measure the e ciency of the procedure, by counting gains and losses on sorting,
and identification. Characteristics of groups of volunteers (age and school level) did not influence
significantly the e ciency of the procedure, and generally results of volunteers and experts matched.info:eu-repo/semantics/publishedVersio
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