EFFECTS OF CHEMOGENETIC INHIBITION OF VENTRAL HIPPOCAMPAL GLUTAMATERGIC NEURONS ON ANXIETY-LIKE DEFENSIVITY IN MALE LONG-EVANS HOODED RATS

Previous research in rodents and humans has implicated the ventral hippocampus in regulating anxiety. However, many rodent studies examining ventral hippocampal neuronal pathways have utilized lesions that create nonspecific and/or nonreversible damage to the region. The present study sought to characterize the role of ventral hippocampal glutamatergic pyramidal neurons in modulating anxiety-like behavior during exposure to a variety of threatening stimuli. Five weeks prior to testing, male Long-Evans hooded rats received ventral hippocampal viral-vector infusions expressing either pAAV-CaMKIIα-hM4D-mCherry (DREADD) or pAAV-CaMKIIa-EGFP (GFP). DREADD transfection allowed for the specific, noninvasive and temporary inhibition of ventral hippocampal glutamatergic neurons immediately before threat presentation. Rats were evaluated for behaviors congruent with anxiety- or fear-like defensive states (e.g., freezing, risk assessment, avoidance, etc.) during testing in the elevated plus-maze and light-dark exploration test, or footshock-induced contextually conditioned fear, respectively. Analyses revealed a significant effect of DREADD inhibition that was dependent on the type of threat exposure. Specifically, compared to GFP controls, DREADD-induced silencing of ventral hippocampal glutamatergic neurons reduced anxiety-like behavior in the elevated plus-maze and light-dark test, without reliably affecting the expression of conditioned fear. The present results confirm that ventral hippocampal glutamatergic pyramidal neurons are recruited in rats during exposure to anxiety-inducing stimuli. These data add to a growing literature implicating the ventral hippocampus as a key region involved in modulating anxiety-like behaviors in rodents, primates and humans

Generator response following as a primary frequency response control strategy for VSC-HVDC connected offshore wind farms

The present study attempts to collect relevant research on the subject of synthetic inertia control strategies for VSC-HVDC transmission links, particularly those connected to offshore windfarms. A number of ideas have been proposed in literature. First, various control strategies at the grid side converter interfacing the DC link with the AC power system are presented. This includes strategies exploiting the power-frequency relationship that naturally exists in AC systems with a high X/R ratio. Other strategies utilize the voltage-frequency relationship that exists when the DC link capacitor is asked to provide active power injection or absorption in response to frequency deviations. Then some coordinated strategies are outlined which build upon and combine other strategies (including those associated with traditional synchronous machines) in order to enhance the operational capability of the decoupled non-synchronous system with respect to synthetic inertia services. Some options for communication are also identified

Local conditions vs regional context: variation in composition of bird communities along the Middle Paraná River, an extensive river-floodplain system of South America

We studied spatial changes in species composition (i.e., beta diversity) of local assemblages of birds along ∼450 km of the Middle Paraná River, an extensive fluvial system of South America. Point counts were used to survey birds at 60 plots located in shrub swamps and marshes of the floodplain within four sites (15 plots per site). Two sites were surrounded by each of the two upland ecoregions. Beta diversity of bird assemblages was high and was more important than alpha diversity in shaping regional diversity (i.e., gamma diversity) of the fluvial system. Compositional changes were related to species turnover among plots, while nestedness dissimilarity was not important for shaping diversity patterns. Variation-partitioning analysis showed that local conditions (i.e., landscape composition within a radius of 200 m from the center of each plot) accounted for more spatial variation in assemblage composition than did location along the fluvial system. Adjacent upland ecoregions did not account for spatial changes in bird composition within the fluvial system. In conclusion, environmental heterogeneity created by flood pulses is an important factor for sustaining regional diversity of birds within the fluvial system through effects on beta diversity

Stress detection using wearable physiological and sociometric sensors

Stress remains a significant social problem for individuals in modern societies. This paper presents a machine learning approach for the automatic detection of stress of people in a social situation by combining two sensor systems that capture physiological and social responses. We compare the performance using different classifiers including support vector machine, AdaBoost, and k-nearest neighbour. Our experimental results show that by combining the measurements from both sensor systems, we could accurately discriminate between stressful and neutral situations during a controlled Trier social stress test (TSST). Moreover, this paper assesses the discriminative ability of each sensor modality individually and considers their suitability for real time stress detection. Finally, we present an study of the most discriminative features for stress detection

MIRD Pamphlet No 28, Part 1: MIRDcalc-A Software Tool for Medical Internal Radiation Dosimetry

Medical internal radiation dosimetry constitutes a fundamental aspect of diagnosis, treatment, optimization, and safety in nuclear medicine. The MIRD committee of the Society of Nuclear Medicine and Medical Imaging developed a new computational tool to support organ-level and suborgan tissue dosimetry (MIRDcalc, version 1). Based on a standard Excel spreadsheet platform, MIRDcalc provides enhanced capabilities to facilitate radiopharmaceutical internal dosimetry. This new computational tool implements the well-established MIRD schema for internal dosimetry. The spreadsheet incorporates a significantly enhanced database comprising details for 333 radionuclides, 12 phantom reference models (International Commission on Radiological Protection), 81 source regions, and 48 target regions, along with the ability to interpolate between models for patient-specific dosimetry. The software also includes sphere models of various composition for tumor dosimetry. MIRDcalc offers several noteworthy features for organ-level dosimetry, including modeling of blood source regions and dynamic source regions defined by user input, integration of tumor tissues, error propagation, quality control checks, batch processing, and report-preparation capabilities. MIRDcalc implements an immediate, easy-to-use single-screen interface. The MIRDcalc software is available for free download (www.mirdsoft.org) and has been approved by the Society of Nuclear Medicine and Molecular Imaging

Detection of helicoidal motion in the optical jet of PKS 0521-365

The jet activity of active galactic nuclei (AGNs), and its interaction with the interstellar medium, may play a pivotal role in the processes that regulate the growth and star formation of its host galaxy. Observational evidence that pinpoints the conditions of such interaction is paramount to unveil the physical processes involved. We report on the discovery of extended emission-line regions exhibiting an S-shaped morphology along the optical jet of the radioloud AGN PKS 0521-365 (z = 0.055), by using long-slit spectroscopic observations obtained with FOcal Reducer/low dispersion Spectrograph 2 on the Very Large Telescope. The velocity pattern derived from the [O II].3727 angstrom, H beta lambda 4861 angstrom and [O III] lambda lambda 4959, 5007 angstrom emission lines is well fitted by a sinusoidal function of the form: v(r) = alpha r(1/2)sin(beta r(1/2) + gamma), suggesting helicoidal motions along the jet up to distances of 20 kpc. We estimate a lower limit for the mass of the outflowing ionized gas along the jet of similar to 10(4)M(circle dot). Helical magnetic fields and jet precession have been proposed to explain helicoidal paths along the jet at pc scales; nevertheless, it is not clear yet whether these hypotheses may hold at kpc scales