The role of the inferior colliculus in a genetic model of audiogenic seizures.

Previous studies have shown the functional importance of the inferior colliculus (IC) for the propagation and initiation of audiogenic seizures in several models of epilepsy in rats. A review of the cell types and cytoarchitecture of the IC, including its three major subdivisions, is presented. Significant increases in GABA levels and the number of GABAergic neurons are found in the central nucleus of the IC (ICCN) of genetically epilepsy-prone rats (GEPR-9s) as compared to Sprague-Dawley rats that do not display audiogenic seizures. Two independent anatomical methods were used to determine the number of GABAergic neurons, immunocytochemistry and in situ hybridization. In both types of preparation, the labeled cells in the ICCN appeared to be of different sizes but the number of small cells with diameters less than 15 microns showed the greatest increase. Nissl-stained sections showed that the total number of neurons in the ICCN was increased in GEPR-9s and indicated that the increase in GABAergic neurons was not due to a change in the phenotype of collicular neurons from non-GABAergic to GABAergic. The number of small neurons in Nissl-stained sections of the ICCN was shown to correlate with seizure severity in the offspring of crosses made between Sprague-Dawley rats and GEPR-9s. Furthermore, the GEPR-3s that display moderate seizures showed a significant increase in the number of small neurons in the ICCN, and the magnitude of this increase was predicted from this correlation. Finally, the use of knife cuts through the midbrain indicated that the ICCN sends an important projection to the external nucleus and that this projection plays a vital role in the propagation of seizure activity from the site of seizure initiation in the ICCN. It remains to be resolved how the increase in small GABAergic neurons in the ICCN is responsible for the known pharmacological defects observed at GABAergic synapses

Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal

Magnetoelectric interaction and transport behaviours in magnetic nanocomposite thermoelectric materials

How to suppress the performance deterioration of thermoelectric materials in the intrinsic excitation region remains a key challenge. The magnetic transition of permanent magnet nanoparticles from ferromagnetism to paramagnetism provides an effective approach to finding the solution to this challenge. Here, we have designed and prepared magnetic nanocomposite thermoelectric materials consisting of BaFe12O19 nanoparticles and Ba0.3In0.3Co4Sb12 matrix. It was found that the electrical transport behaviours of the nanocomposites are controlled by the magnetic transition of BaFe12O19 nanoparticles from ferromagnetism to paramagnetism. BaFe12O19 nanoparticles trap electrons below the Curie temperature (TC) and release the trapped electrons above the TC, playing an ‘electron repository’ role in maintaining high figure of merit ZT. BaFe12O19 nanoparticles produce two types of magnetoelectric effect—electron spiral motion and magnon-drag thermopower—as well as enhancing phonon scattering. Our work demonstrates that the performance deterioration of thermoelectric materials in the intrinsic excitation region can be suppressed through the magnetic transition of permanent magnet nanoparticles

An inbred epilepsy-prone substrain of BALB/c mice shows absence of the corpus callosum, an abnormal projection to the basal forebrain, and bilateral projections to the thalamus.

BALB/c mice lack a corpus callosum in about 11% of the population. Two inbred substrains of BALB/c mice, epilepsy-prone (EP) and epilepsy-resistant (ER), have been examined to determine whether these substrains differ in regard to corpus callosum morphology. Further, this study addressed the issue of whether misrouted cortical axons form an aberrant pathway instead of the corpus callosum. Initial studies that examined fresh brain tissue of adult animals revealed normal corpora callosa in all ER mice but deficient or absent corpora callosa in all EP mice. Subsequently, Dil crystals were placed in the motor cortices of aldehyde-fixed brains of 2-week-old animals to investigate cortical projections in both inbred substrains of mice. Fluorescent microscopy revealed that all of the ER animals had normal corpora callosa, whereas all EP animals exhibited either reduced corpora callosa (partially callosal) or an absence (acallosal) of this structure. Both acallosal and partially callosal EP mice displayed an extensive, aberrant projection to the basal forebrain as well as bilateral projections to midline and intralaminar thalamic nuclei. The fibers projecting to the basal forebrain arose from the cortex, coursed toward the midline before turning ventrally along the midline, and appeared to terminate in the medial septal nucleus and the nucleus of the diagonal band. ER animals lacked this aberrant cortical projection to the basal forebrain. Electron microscopic results obtained from EP mice indicated that labeled axons in this aberrant pathway formed axosomatic, axodendritic, and axospinous synapses with the neurons in the medial septal/diagonal band complex. The function of the aberrant projection to the basal forebrain remains unknown but it may provide an abnormal excitatory input to a region that provides cholinergic and GABAergic input to the cerebral cortex and hippocampus. The additional projections to midline and contralateral intralaminar thalamic nuclei in EP mice may function to intensify the synchronization of bilateral discharges

Extrastriate body area underlies aesthetic evaluation of body stimuli

Humans appear to be the only animals to have developed the practice and culture of art. This practice presumably relies on special processing circuits within the human brain associated with a distinct subjective experience, termed aesthetic experience, and preferentially evoked by artistic stimuli. We assume that positive or negative aesthetic judgments are an important function of neuroaesthetic circuits. The localization of these circuits in the brain remains unclear, though neuroimaging studies have suggested several possible neural correlates of aesthetic preference. We applied repetitive transcranial magnetic stimulation (rTMS) over candidate brain areas to disrupt aesthetic processing while healthy volunteers made aesthetic preference judgments between pairs of dance postures, or control non-body stimuli. Based on evidence from visual body perception studies, we targeted the ventral premotor cortex (vPMC) and extrastriate body area (EBA), in the left and right hemispheres. rTMS over EBA reduced aesthetic sensitivity for body stimuli relative to rTMS over vPMC, while no such difference was found for non-body stimuli. We interpret our results within the framework of dual routes for visual body processing. rTMS over either EBA or vPMC reduced the contributions of the stimulated area to body processing, leaving processing more reliant on the unaffected route. Disruption of EBA reduces the local processing of the stimuli, and reduced observers’ aesthetic sensitivity. Conversely, disruption of the global route via vPMC increased the relative contribution of the local route via EBA, and thus increased aesthetic sensitivity. In this way, we suggest a complementary contribution of both local and global routes to aesthetic processing

Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics

A detailed study is presented of the expected performance of the ATLAS detector. The reconstruction of tracks, leptons, photons, missing energy and jets is investigated, together with the performance of b-tagging and the trigger. The physics potential for a variety of interesting physics processes, within the Standard Model and beyond, is examined. The study comprises a series of notes based on simulations of the detector and physics processes, with particular emphasis given to the data expected from the first years of operation of the LHC at CERN

Study protocol of effectiveness of a biopsychosocial multidisciplinary intervention in the evolution of non-speficic sub-acute low back pain in the working population : cluster randomised trial

Background: Non-specific low back pain is a common cause for consultation with the general practitioner, generating increased health and social costs. This study will analyse the effectiveness of a multidisciplinary intervention to reduce disability, severity of pain, anxiety and depression, to improve quality of life and to reduce the incidence of chronic low back pain in the working population with non-specific low back pain, compared to usual clinical care. Methods/Design: A Cluster randomised clinical trial will be conducted in 38 Primary Health Care Centres located in Barcelona, Spain and its surrounding areas. The centres are randomly allocated to the multidisciplinary intervention or to usual clinical care. Patients between 18 and 65 years old (n = 932; 466 per arm) and with a diagnostic of a non-specific sub-acute low back pain are included. Patients in the intervention group are receiving the recommendations of clinical practice guidelines, in addition to a biopsychosocial multidisciplinary intervention consisting of group educational sessions lasting a total of 10 hours. The main outcome is change in the score in the Roland Morris disability questionnaire at three months after onset of pain. Other outcomes are severity of pain, quality of life, duration of current non-specific low back pain episode, work sick leave and duration, Fear Avoidance Beliefs and Goldberg Questionnaires. Outcomes will be assessed at baseline, 3, 6 and 12 months. Analysis will be by intention to treat. The intervention effect will be assessed through the standard error of measurement and the effect-size. Responsiveness of each scale will be evaluated by standardised response mean and receiver-operating characteristic method. Recovery according to the patient will be used as an external criterion. A multilevel regression will be performed on repeated measures. The time until the current episode of low back pain takes to subside will be analysed by Cox regression. Discussion: We hope to provide evidence of the effectiveness of the proposed biopsychosocial multidisciplinary intervention in avoiding the chronification of low back pain, and to reduce the duration of non-specific low back pain episodes. If the intervention is effective, it could be applied to Primary Health Care Centres

Making the invisible enemy visible.

Structural biology plays a crucial role in the fight against COVID-19, permitting us to ‘see’ and understand SARS-CoV-2. However, the macromolecular structures of SARS-CoV-2 proteins that were solved with great speed and urgency can contain errors that may hinder drug design. The Coronavirus Structural Task Force has been working behind the scenes to evaluate and improve these structures, making the results freely available at https://insidecorona.net/

The optic nerve head is the site of axonal transport disruption, axonal cytoskeleton damage and putative axonal regeneration failure in a rat model of glaucoma

The neurodegenerative disease glaucoma is characterised by the progressive death of retinal ganglion cells (RGCs) and structural damage to the optic nerve (ON). New insights have been gained into the pathogenesis of glaucoma through the use of rodent models; however, a coherent picture of the early pathology remains elusive. Here, we use a validated, experimentally induced rat glaucoma model to address fundamental issues relating to the spatio-temporal pattern of RGC injury. The earliest indication of RGC damage was accumulation of proteins, transported by orthograde fast axonal transport within axons in the optic nerve head (ONH), which occurred as soon as 8 h after induction of glaucoma and was maximal by 24 h. Axonal cytoskeletal abnormalities were first observed in the ONH at 24 h. In contrast to the ONH, no axonal cytoskeletal damage was detected in the entire myelinated ON and tract until 3 days, with progressively greater damage at later time points. Likewise, down-regulation of RGC-specific mRNAs, which are sensitive indicators of RGC viability, occurred subsequent to axonal changes at the ONH and later than in retinas subjected to NMDA-induced somatic excitotoxicity. After 1 week, surviving, but injured, RGCs had initiated a regenerative-like response, as delineated by Gap43 immunolabelling, in a response similar to that seen after ON crush. The data presented here provide robust support for the hypothesis that the ONH is the pivotal site of RGC injury following moderate elevation of IOP, with the resulting anterograde degeneration of axons and retrograde injury and death of somas