28 research outputs found
A review of the effects of agricultural intensification and the use of pesticides on honey bees and their products and possible palliatives
There is considerable scientific evidence revealing a decrease in pollinating insects in different ecosystems around the world. In this context, agricultural intensification and the use of phytosanitary products are likely the main causes. This problem is common to many pollinators but of particular ecosystemic, economic and bromatological significance for honey bees (Apis mellifera) since their presence in these landscapes is mainly due to the proximity of apiaries for human food production and because they are the most important biotic pollinators of agricultural crops. In this review, we present a synthesis of the results of several years of research on this topic, as well as potential solutions referenced in the bibliography that might help alleviate the effects of contamination on honey bees and their products. Additionally, we expose the possible limits of the real implementation of such solutions and conclude on the need to implement land-use planning strategies for agricultural systems. Without mitigating actions in the short term, the sustainability of agricultural ecosystems as bee-friendly habitats and the production of foods suitable for human consumption are uncertain.Fil: Blettler, Diego César. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; ArgentinaFil: Biurrun Manresa, José Alberto. Universidad Nacional de Entre Ríos. Instituto de Investigación y Desarrollo en Bioingeniería y Bioinformática - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación y Desarrollo en Bioingeniería y Bioinformática; ArgentinaFil: Fagundez, Guillermina Andrea. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentin
Variability and effect sizes of intracranial current source density estimations during pain: Systematic review, experimental findings, and future perspectives
Pain arises from the integration of sensory and cognitive processes in the brain, resulting in specific patterns of neural oscillations that can be characterized by measuring electrical brain activity. Current source density (CSD) estimation from low-resolution brain electromagnetic tomography (LORETA) and its standardized (sLORETA) and exact (eLORETA) variants, is a common approach to identify the spatiotemporal dynamics of the brain sources in physiological and pathological pain-related conditions. However, there is no consensus on the magnitude and variability of clinically or experimentally relevant effects for CSD estimations. Here, we systematically examined reports of sample size calculations and effect size estimations in all studies that included the keywords pain, and LORETA, sLORETA, or eLORETA in Scopus and PubMed. We also assessed the reliability of LORETA CSD estimations during non-painful and painful conditions to estimate hypothetical sample sizes for future experiments using CSD estimations. We found that none of the studies included in the systematic review reported sample size calculations, and less than 20% reported measures of central tendency and dispersion, which are necessary to estimate effect sizes. Based on these data and our experimental results, we determined that sample sizes commonly used in pain studies using CSD estimations are suitable to detect medium and large effect sizes in crossover designs and only large effects in parallel designs. These results provide a comprehensive summary of the effect sizes observed using LORETA in pain research, and this information can be used by clinicians and researchers to improve settings and designs of future pain studies.Fil: Völker, Juan Manuel. Aalborg University; DinamarcaFil: Arguissain, Federico Gabriel. Aalborg University; DinamarcaFil: Kæseler Andersen, Ole. Aalborg University; DinamarcaFil: Biurrun Manresa, José Alberto. Aalborg University; Dinamarca. Universidad Nacional de Entre Ríos. Instituto de Investigación y Desarrollo en Bioingeniería y Bioinformática - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación y Desarrollo en Bioingeniería y Bioinformática; Argentin
Stimulus predictability moderates the withdrawal strategy in response to repetitive noxious stimulation in humans
Nociceptive withdrawal reflex (NWR) is a protective reaction to a noxious stimulus, resulting in withdrawal of the affected area and thus preventing potential tissue damage. This involuntary reaction consists of neural circuits, biomechanical strategies, and muscle activity that ensure an optimal withdrawal. Studies of lower limb NWR indicate that the amplitude of the NWR is highly modulated by extrinsic and intrinsic factors, such as stimulation site, intensity, frequency, and supraspinal activity, among others. Whether the predictability of the stimulus has an effect on the biomechanical strategies is still unclear. This study aimed to evaluate how the predictability of impending noxious stimuli modulate the NWR reaction in the lower limb. NWR was evoked on fifteen healthy participants by trains of electrical stimuli on the sole of the foot and was measured in one distal (tibialis anterior) and one proximal (biceps femoris) muscle. The predictability was manipulated by giving participants prior information about the onset of the stimulus trains and the number of delivered stimuli per train. Results showed that the predictability of the incoming stimuli differentially modulates the muscle activity involved in the NWR reaction. For the most unpredictable stimulus train, larger NWR at distal muscles were evoked. Furthermore, the stereotyped temporal summation profile to repeated stimulation was observed when the stimulus train was completely predictable, while it was disrupted in proximal muscles in unpredictable conditions. It is inferred that the reflex response is shaped by descending control, which dynamically tunes the activity of the muscles involved in the resulting reaction. NEW & NOTEWORTHY Innate defensive behaviors such as reflexes are found across all species, constituting preprogrammed responses to external threats that are not anticipated. Previous studies indicated that the excitability of the reflex arcs like spinal nociceptive withdrawal reflex (NWR) pathways in humans are modulated by several cognitive factors. This study assesses how the predictability of a threat affects the biomechanical pattern of the withdrawal response, showing that distal and proximal muscles are differentially modulated by descending control.Fil: Jure, Fabricio A.. Aalborg University; DinamarcaFil: Arguissain, Federico G.. Aalborg University; DinamarcaFil: Biurrun Manresa, José Alberto. Universidad Nacional de Entre Ríos. Instituto de Investigación y Desarrollo en Bioingeniería y Bioinformática - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación y Desarrollo en Bioingeniería y Bioinformática; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Entre Ríos. Universidad Nacional de Entre Ríos. Centro de Investigaciones y Transferencia de Entre Ríos; Argentina. Aalborg University; DinamarcaFil: Graven Nielsen, Thomas. Aalborg University; DinamarcaFil: Andersen, Ole Kæseler. Aalborg University; Dinamarc
Perceptual correlates of homosynaptic long-term potentiation in human nociceptive pathways: A replication study
Animal studies have shown that high-frequency stimulation (HFS) of peripheral C-fibres induces long-term potentiation (LTP) within spinal nociceptive pathways. The aim of this replication study was to assess if a perceptual correlate of LTP can be observed in humans. In 20 healthy volunteers, we applied HFS to the left or right volar forearm. Before and after applying HFS, we delivered single electrical test stimuli through the HFS electrode while a second electrode at the contra-lateral arm served as a control condition. Moreover, to test the efficacy of the HFS protocol, we quantified changes in mechanical pinprick sensitivity before and after HFS of the skin surrounding both electrodes. The perceived intensity was collected for both electrical and mechanical stimuli. After HFS, the perceived pain intensity elicited by the mechanical pinprick stimuli applied on the skin surrounding the HFS-treated site was significantly higher compared to control site (heterotopic effect). Furthermore, we found a higher perceived pain intensity for single electrical stimuli delivered to the HFS-treated site compared to the control site (homotopic effect). Whether the homotopic effect reflects a perceptual correlate of homosynaptic LTP remains to be elucidated.Fil: van de Broeke, Emanuel N.. Université Catholique de Louvain; BélgicaFil: Vanmaele, Tessa. Katholikie Universiteit Leuven; BélgicaFil: Mouraux, André. Université Catholique de Louvain; BélgicaFil: Stouffs, Alexandre. Université Catholique de Louvain; BélgicaFil: Biurrun Manresa, José Alberto. Universidad Nacional de Entre Ríos. Instituto de Investigación y Desarrollo en Bioingeniería y Bioinformática - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación y Desarrollo en Bioingeniería y Bioinformática; ArgentinaFil: Torta, Diana M.. Katholikie Universiteit Leuven; Bélgic
Psychophysical and electrophysiological evidence for enhanced pain facilitation and unaltered pain inhibition in acute low back pain patients
The aim of this case-control study was to examine differences in neural correlates of pain facilitatory and inhibitory mechanisms between acute low back pain (LBP) patients and healthy individuals. Pressure pain tolerance, electrical pain detection thresholds, pain ratings to repetitive suprathreshold electrical stimulation (SES) and conditioned pain modulation (CPM) were assessed in 18 patients with acute LBP and 18 healthy control participants. Furthermore, event-related potentials (ERPs) in response to repetitive SES were obtained from high-density electroencephalography. Results showed that the LBP group presented lower pressure pain tolerance and higher pain ratings to SES compared with the control group. Both groups displayed effective CPM, with no differences in CPM magnitude between groups. Both groups presented similar reductions in ERP amplitudes during CPM, but ERP responses to repetitive SES were significantly larger in the LBP group. In conclusion, acute LBP patients presented enhanced pain facilitatory mechanisms, whereas no significant changes in pain inhibitory mechanisms were observed. These results provide new insight into the central mechanisms underlying acute LBP. Perspective: This article present evidence that acute LBP patients show enhanced pain facilitation and unaltered pain inhibition compared with pain-free volunteers. These results provide new insight into the central mechanisms underlying acute LBP.Fil: Vuilleumier, Pascal Henri. University of Bern; SuizaFil: Arguissain, Federico Gabriel. Aalborg University; DinamarcaFil: Biurrun Manresa, José Alberto. Aalborg University; Dinamarca. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Entre Rios. Universidad Nacional de Entre Rios. Centro de Investigaciones y Transferencia de Entre Rios; ArgentinaFil: Neziri, Alban Ymer. University of Bern; Suiza. Regional Hospital of Langenthal; SuizaFil: Nirkko, Arto Christian. University of Bern; SuizaFil: Andersen, Ole Kæseler. Aalborg University; DinamarcaFil: Arendt-Nielsen, Lars. Aalborg University; DinamarcaFil: Curatolo, Michele. Aalborg University; Dinamarca. University of Washington; Estados Unido
Electrophysiological techniques:assessment of spinal nociceptive processing using the withdrawal reflex
What Is a Bayes Factor?
The use of Bayes factors is becoming increasingly common in psychological sciences. Thus, it is important that researchers understand the logic behind the Bayes factor in order to correctly interpret it, and the strengths of weaknesses of the Bayesian approach. As education for psychological scientists focuses on frequentist statistics, resources are needed for researchers and students who want to learn more about this alternative approach. The aim of the current article is to provide such an overview to a psychological researcher. We cover the general logic behind Bayesian statistics, explain how the Bayes factor is calculated, how to set the priors in popular software packages to reflect the prior beliefs of the researcher, and finally provide a set of recommendations and caveats for interpreting Bayes factors.Fil: Schmalz, Xenia. Ludwig Maximilians Universitat; Alemania. Universita degli Studi di Trento; ItaliaFil: Biurrun Manresa, José Alberto. Universidad Nacional de Entre Ríos. Instituto de Investigación y Desarrollo en Bioingeniería y Bioinformática - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación y Desarrollo en Bioingeniería y Bioinformática; ArgentinaFil: Zhang, Lei. Universidad de Viena; Austri
High-frequency conditioning electrical stimulation of glabrous skin failed to induce heterotopic long-term potentiation (LTP)
System and method for determining nociceptive withdrawal reflex threshold and quantifying a reflex receptive field
Modelo a escala ciudad de la epidemiología de COVID-19 con movilidad de personas y sus actividades representadas por un conjunto de Modelos Ocultos de Márkov
In this paper, an agent-based model that predicts a daily evolution of the number of people hospitalized in intensive care due to COVID-19 is presented, including results for 2020. In addition, the number of deaths, reported cases, asymptomatic individuals and other epidemiological variables of interest, discriminated by age range, are considered. The most relevant characteristics of the climate in Paraná city (Entre Ríos, Argentina), its social dynamics and public transportation are considered as inputs, taking also into account the different phases of isolation and social distancing. By means of a set of Hidden Markov Models, the system reproduces virus transmission associated with people’s mobility and activities in the city. Spread of the virus in the host is also simulated by following the stages of the disease, and by considering the existence of comorbidities and a proportion of asymptomatic infected people. By adjusting the model to match the data on hospitalizations in intensive care units and deaths due to COVID-19 in the city under study, the system can be operated to analyze the impact of isolation and social distancing measures on the population dynamics. In addition, it allows simulating combinations of characteristics leading to a potential collapse in the health system due to lack of infrastructure, as well as predicting the impact of social events or the increase in people’s mobility.En este artículo se presenta un modelo que predice la evolución semanal de la cantidad de internados con COVID-19 en terapia intensiva, mostrando resultados durante el transcurso de 2020. Además devuelve la cantidad de fallecidos, casos reportados, asintomáticos y otras variables epidemiológicas de interés, discriminadas por rango etario. Para esto se tienen en cuenta como entradas las características más relevantes del clima de la ciudad de Paraná, su dinámica social y del transporte público de pasajeros, considerando las diferentes fases de aislamiento y distanciamiento. El modelo reproduce la transmisión del virus asociado a los desplazamientos y actividades de las personas dentro de la ciudad, mediante un conjunto de Modelos Ocultos de Markov. A su vez, se simula la propagación del virus en el huésped siguiendo las etapas de la enfermedad, asumiendo la existencia de comorbilidades y de una proporción de infectados asintomáticos. Al ajustar el modelo propuesto con los datos de internados en terapia intensiva y fallecidos por COVID-19 en la ciudad en estudio, el mismo permite ser operado para analizar el impacto de las características del aislamiento y distanciamiento social en la dinámica de la población y predecir el número de internados y muertes por COVID-19. Además, permite simular combinaciones de las características que llevarían a un potencial colapso del sistema de salud por falta de infraestructura, así como también predecir el impacto de eventos sociales o aumento de la movilidad de las personas