145 research outputs found
The detection of gear noise computed by integrating the Fourier and Wavelet methods
This paper presents a new gearbox noise detection algorithm based on analyzing specific points
of vibration signals using the Wavelet Transform. The proposed algorithm is compared with a previouslydeveloped
algorithm associated with the Fourier decomposition using Hanning windowing. Simulation
carried on real data demonstrate that the WT algorithm achieves a comparable accuracy while having a lower
computational cost. This makes the WT algorithm an appropriate candidate for fast processing of noise gear box
Brain Circuits Responsible for Seizure Generation, Propagation, and Control: Insights from Preclinical Research
Colocalization of Tectal Inputs With Amygdala-Projecting Neurons in the Macaque Pulvinar
Neuropsychological and neuroimaging studies have suggested the presence of a fast, subcortical route for the processing of emotionally-salient visual information in the primate brain. This putative pathway consists of the superior colliculus (SC), pulvinar and amygdala. While the presence of such a pathway has been confirmed in sub-primate species, it has yet to be documented in the primate brain using conventional anatomical methods. We injected retrograde tracers into the amygdala and anterograde tracers into the colliculus, and examined regions of colocalization of these signals within the pulvinar of the macaque. Anterograde tracers injected into the SC labeled axonal projections within the pulvinar, primarily within the oral, lateral and medial subdivisions. These axonal projections from the colliculus colocalized with cell bodies within the pulvinar that were labeled by retrograde tracer injected into the lateral amygdala. This zone of overlap was most notable in the medial portions of the medial (PM), oral (PO) and inferior pulvinar (PI), and was often densely concentrated in the vicinity of the brachium of the SC. These data provide an anatomical basis for the previously suggested pathway mediating fast processing of emotionally salient information
the influence of pregnancy and the beginning of lactation on pelage traits in cashmere goats
The aim of this study was to investigate the effect of pregnancy followed by the beginning of lactation on fibre traits incashmere goats. Two groups of cashmere-bearing goats aged between 2-3 years were used. The control group (A) included12 non-lactating, non-pregnant subjects. The experimental group (B) included 12 goats mated during the first weekof June, in order to have pregnancy and the beginning of lactation coincide with the period when cashmere normallygrows. As expected, Liveweight significantly varied in Group B during the last two months of pregnancy, when foetalgrowth reaches its maximum, and following delivery. Hair patch weight, because of the continuous growth of primary andsecondary fibres, increased significantly during the trial (P<0.001). The physiological status considered negatively affected(P<0.05) the total mean growth rate of cashmere fibres and, as a result, their length. Cashmere daily growth ratevalues varied significantly (P<0.05) throughout the experiment, while the effect of the physiological status was notedonly in November – December. Furthermore, this parameter also seems to be influenced by climatic factors and, in particular,environmental temperature, as shown by the negative correlation (r = - 0.28; P<0.05) between cashmere dailygrowth rate and environmental temperature. Guard hair length and growth rate did not differ between the two groups,however, they were influenced by time. Cashmere yield and cashmere production were lower in group B (P<0.05). Nodifferences between groups were observed for cashmere diameter. Overall, pregnancy and the consequent period of lactationnegatively influenced cashmere rather than guard hair fibres. These negative effects were noted in quantitativeterms as yield and production dropped by 37% and 43%, respectively. We hypothesise that the complete overlap of pregnancyand lactation with the period of cashmere growth reduced the number of secondary active follicles and their degreeof activity and caused an increase in competition for the partitioning of nutrients between hair follicles and the graviduterus, first, and then the mammary gland, later
The piriform, perirhinal, and entorhinal cortex in seizure generation.
Understanding neural network behavior is essential to shed light on epileptogenesis and seizure propagation. The interconnectivity and plasticity of mammalian limbic and neocortical brain regions provide the substrate for the hypersynchrony and hyperexcitability associated with seizure activity. Recurrent unprovoked seizures are the hallmark of epilepsy, and limbic epilepsy is the most common type of medically-intractable focal epilepsy in adolescents and adults that necessitates surgical evaluation. In this review, we describe the role and relationships among the piriform (PIRC), perirhinal (PRC), and entorhinal cortex (ERC) in seizure-generation and epilepsy. The inherent function, anatomy, and histological composition of these cortical regions are discussed. In addition, the neurotransmitters, intrinsic and extrinsic connections, and the interaction of these regions are described. Furthermore, we provide evidence based on clinical research and animal models that suggest that these cortical regions may act as key seizure-trigger zones and, even, epileptogenesis
Phenobarbital does not worsen outcomes of neonatal hypoxia on hippocampal LTP on rats
IntroductionNeonatal hypoxia is a common cause of early-life seizures. Both hypoxia-induced seizures (HS), and the drugs used to treat them (e.g., phenobarbital, PB), have been reported to have long-lasting impacts on brain development. For example, in neonatal rodents, HS reduces hippocampal long-term potentiation (LTP), while PB exposure disrupts GABAergic synaptic maturation in the hippocampus. Prior studies have examined the impact of HS and drug treatment separately, but in the clinic, PB is unlikely to be given to neonates without seizures, and neonates with seizures are very likely to receive PB. To address this gap, we assessed the combined and separate impacts of neonatal HS and PB treatment on the development of hippocampal LTP.MethodsMale and female postnatal day (P)7 rat pups were subjected to graded global hypoxia (or normoxia as a control) and treated with either PB (or vehicle as a control). On P13-14 (P13+) or P29-37 (P29+), we recorded LTP of the Schaffer collaterals into CA1 pyramidal layer in acute hippocampal slices. We compared responses to theta burst stimulation (TBS) and tetanization induction protocols.ResultsUnder the TBS induction protocol, female rats showed an LTP impairment caused by HS, which appeared only at P29+. This impairment was delayed compared to male rats. While LTP in HS males was impaired at P13+, it normalized by P29+. Under the tetanization protocol, hypoxia produced larger LTP in males compared to female rats. PB injection, under TBS, did not exacerbate the effects of hypoxia. However, with the tetanization protocol, PB – on the background of HS – compensated for these effects, returning LTP to control levels.DiscussionThese results point to different susceptibility to hypoxia as a function of sex and age, and a non-detrimental effect of PB when administered after hypoxic seizures
El estornino pinto en Argentina: desafíos y prioridades
El día 11 de septiembre de 2015 se desarrolló la mesa redonda “Invasión del estornino pinto (Sturnus vulgaris) en Argentina”, en el marco de la XVI Reunión Argentina de Ornitología organizada por la Sección Ornitología del Museo de La Plata (Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata). En esa oportunidad se informó acerca de las características de la especie, de las consecuencias de su introducción en distintos países, del estado actual de la invasión en Argentina y de los antecedentes relacionados con su control. Además, se realizó una actividad en la que los participantes propusieron medidas de acción prioritarias para el manejo de la especie a nivel local, regional y nacional. En esta contribución resumimos los aspectos más relevantes de la reunión y las conclusiones de la misma
European starling in Argentina: challenges and priorities
El día 11 de septiembre de 2015 se desarrolló la mesa redonda “Invasión del estornino pinto (Sturnus vulgaris) en Argentina”, en el marco de la XVI Reunión Argentina de Ornitología organizada por la Sección Ornitología del Museo de La Plata (Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata). En esa oportunidad se informó acerca de las características de la especie, de las consecuencias de su introducción en distintos países, del estado actual de la invasión en Argentina y de los antecedentes relacionados con su control. Además, se realizó una actividad en la que los participantes propusieron medidas de acción prioritarias para el manejo de la especie a nivel local, regional y nacional. En esta contribución resumimos los aspectos más relevantes de la reunión y las conclusiones de la misma.On September 11 2015 we held a round table called “Invasion of the European starling (Sturnus vulgaris) in Argentina”, in the framework of the XVI Reunión Argentina de Ornitología, organized by the Ornithology section of the Museum of La Plata (Faculty of Natural Sciences and Museum, National University of La Plata).
We reported on the characteristics of the European starlings, on the consequences of the introduction of this species in different countries and on the current state of their invasion in Argentina and antecedents of control strategies. Additionally, we performed an activity where the participants proposed priority actions for the management of this species at a local, regional and national scale. In this contribution we summarize the most important items and conclusions of the meeting.Facultad de Ciencias Naturales y Muse
European starling in Argentina: challenges and priorities
El día 11 de septiembre de 2015 se desarrolló la mesa redonda “Invasión del estornino pinto (Sturnus vulgaris) en Argentina”, en el marco de la XVI Reunión Argentina de Ornitología organizada por la Sección Ornitología del Museo de La Plata (Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata). En esa oportunidad se informó acerca de las características de la especie, de las consecuencias de su introducción en distintos países, del estado actual de la invasión en Argentina y de los antecedentes relacionados con su control. Además, se realizó una actividad en la que los participantes propusieron medidas de acción prioritarias para el manejo de la especie a nivel local, regional y nacional. En esta contribución resumimos los aspectos más relevantes de la reunión y las conclusiones de la misma.On September 11 2015 we held a round table called “Invasion of the European starling (Sturnus vulgaris) in Argentina”, in the framework of the XVI Reunión Argentina de Ornitología, organized by the Ornithology section of the Museum of La Plata (Faculty of Natural Sciences and Museum, National University of La Plata).
We reported on the characteristics of the European starlings, on the consequences of the introduction of this species in different countries and on the current state of their invasion in Argentina and antecedents of control strategies. Additionally, we performed an activity where the participants proposed priority actions for the management of this species at a local, regional and national scale. In this contribution we summarize the most important items and conclusions of the meeting.Facultad de Ciencias Naturales y Muse
PEDOT:PSS interfaces support the development of neuronal synaptic networks with reduced neuroglia response in vitro
The design of electrodes based on conductive polymers in brain-machine interface technology offers the opportunity to exploit variably manufactured materials to reduce gliosis, indeed the most common brain response to chronically implanted neural electrodes. In fact, the use of conductive polymers, finely tailored in their physical-chemical properties, might result in electrodes with improved adaptability to the brain tissue and increased charge-transfer efficiency. Here we interfaced poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) doped with different amounts of ethylene glycol (EG) with rat hippocampal primary cultures grown for 3 weeks on these synthetic substrates. We used immunofluorescence and scanning electron microscopy combined to single cell electrophysiology to assess the biocompatibility of PEDOT:PSS in terms of neuronal growth and synapse formation. We investigated neuronal morphology, density and electrical activity. We reported the novel observation that opposite to neurons, glial cell density was progressively reduced, hinting at the ability of this material to down regulate glial reaction. Thus PEDOT:PSS is an attractive candidate for the design of new implantable electrodes, controlling the extent of glial reactivity without affecting neuronal viability and function
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