Functional and Structural Investigation of Songbird Brain Projection Neurons with Shuttle and Find

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7-August 11, 201

Reproductive capacity of the red cusk-eel genypterus chilensis (Guichenot, 1848) in captivity

Indexación: Scopus.This work was supported by the FONDEF Project D06I 1024 “Development of technologies for the production of red cusk-eel fingerlings (Genypterus chilensis)”.Genypterus chilensis is a marine fish of high gastronomic demand, whose capture has declined in recent years due to overfishing. In the development of the farming technology, high mortalities were obtained during egg incubation. The objective of this study is to contribute to the knowledge of fecundity and eggs viability of G. chilensis in captivity. The spawns of G. chilensis were analyzed over a period of 2 years and 3 months. The total fecundity was estimated by counting the masses and eggs produced monthly throughout the period. The results confirm that G. chilensis is a partial spawner, since a female may more than two masses of eggs per day, due to a large amount of mass spawned per season (621 average). The total production of masses of the Farming Centre during the period was 2,290; of these, only 7% (166) corresponding to 15,330,517 eggs were incubated. Because of its high fecundity, G. chilensis produces numerous masses of eggs, of which only a small percentage reaches incubation, as well as it occurs in other marine fish. © 2018, Escuela de Ciencias del Mar. All rights reserved.https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0718-560X201800020048

On-sky results of the adaptive optics MACAO for the new IR-spectrograph CRIRES at VLT

The adaptive optics MACAO has been implemented in 6 focii of the VLT observatory, in three different flavors. We present in this paper the results obtained during the commissioning of the last of these units, MACAO-CRIRES. CRIRES is a high-resolution spectrograph, which efficiency will be improved by a factor two at least for point-sources observations with a NGS brighter than R=15. During the commissioning, Strehl exceeding 60% have been observed with fair seeing conditions, and a general description of the performance of this curvature adaptive optics system is done.Comment: SPIE conference 2006, Advances in adaptive optics, 12 pages, 11 figure

The numerical simulation tool for the MAORY multiconjugate adaptive optics system

The Multiconjugate Adaptive Optics RelaY (MAORY) is and Adaptive Optics module to be mounted on the ESO European-Extremely Large Telescope (E-ELT). It is a hybrid Natural and Laser Guide System that will perform the correction of the atmospheric turbulence volume above the telescope feeding the Multi-AO Imaging Camera for Deep Observations Near Infrared spectro-imager (MICADO). We developed an end-to-end Monte- Carlo adaptive optics simulation tool to investigate the performance of a the MAORY and the calibration, acquisition, operation strategies. MAORY will implement Multiconjugate Adaptive Optics combining Laser Guide Stars (LGS) and Natural Guide Stars (NGS) measurements. The simulation tool implements the various aspect of the MAORY in an end to end fashion. The code has been developed using IDL and uses libraries in C++ and CUDA for efficiency improvements. Here we recall the code architecture, we describe the modeled instrument components and the control strategies implemented in the code.Comment: 6 pages, 1 figure, Proceeding 9909 310 of the conference SPIE Astronomical Telescopes + Instrumentation 2016, 26 June 1 July 2016 Edinburgh, Scotland, U

A Technical-Economic Comparison between Conventional Tillage and Conservative Techniques in Paddy-Rice Production Practice in Northern Italy

In this study a technical-economic comparison was conducted to compare three different agronomic practices applied to paddy rice cultivation areas in Italy: one based on conventional tillage (CT), and two adopting conservative agriculture approaches, namely minimum tillage (MT) and no-tillage (NT). Data about production inputs (seed, fertilizers, agrochemicals, fuel) and working time were measured for each technique during the whole production season in three experimental fields. The total production costs were computed by adding the mechanization costs, calculated through the ASABE (American Society of Agricultural and Biological Engineers) EP (Engineering Practice) 496.3 methodology, and the production input costs. The results of the study highlighted a significant reduction of total costs obtained with both minimum ( 1216%) and no-tillage ( 1219%) compared to conventional tillage

Order of [6]Ti4+ in a Ti-rich calcium amphibole from Kaersut, Greenland : a combined X-ray and neutron diffraction study

In order to characterize the role of Ti in the crystal structure of calcium amphiboles with high or even dominant oxo-component, the crystal structure of a Ti-rich calcium amphibole from a gabbro at Kaersut, Greenland, has been refined with single-crystal MoK\u3b1 X-ray intensity data to an R1(F) index of ~0.025, and with single-crystal Laue neutron intensity data to an R1(F) index of ~0.053. The crystal used for X-ray structure refinement was characterized by electron- and ion-microprobe analysis. The site populations of the C-group cations Mg, Fe and Ti were calculated from the refined site-scattering values for the M(1), M(2) and M(3) sites derived by both X-ray and neutron diffraction. Ti is distributed among all the three sixfold coordinated M sites, with a strong preference for the M(1) and M(3) sites, where its main role is maintaining electroneutrality at the deprotonated O(3) site. The pattern of distortion of the M(1), M(2) and M(3) octahedra differs from that in F-free deprotonated or partly deprotonated amphiboles, where Ti4+ does not occur at the M(3) site. The neutron structure refinement provides also a clear picture of the environment of the proton, anisotropic displacement behaviour and potential hydrogen-bonding arrangements. A trifurcated hydrogen-bonding configuration has been identified, with two O(6) and one O(7) oxygen atoms as acceptors of weak hydrogen-bonds

Comparison of the effectiveness of different mechanical tools for the termination of cover crops using a modular prototype

Cover crops are crops that occupy the soil between the end of a cash crop and the beginning of the next one, providing both agronomic and environmental benefits. To allow for the subsequent cultivation of the cash crop, cover crops must undergo an appropriate termination process based on winter frost, herbicide chemical treatments, or mechanical methods. For this latter approach, previous published research has only examined the effectiveness of termination obtained with individual mechanical tools without considering the possible synergistic effects of multiple tools with complementary actions. To address this gap, a modular multi-tool prototype has been developed in this work. It allows for the evaluation of the effects of different types of tools, both individually and in combination. The working modules of the prototype include: 1) tine cultivator; 2) disk harrow; and 3) crimper roller. Field trials were carried out in 2021 and 2022 on three fields of approximately 6000 m2, which were divided into 60 plots each and sown with vetch and barley. The plots were mechanically terminated with the prototype in different configurations, and the effectiveness of the different modules and their combinations was subsequently evaluated by measuring the NDVI index using ground sensing technology. The results indicate that the disk harrow 15°, used alone and in combination with other tools considered (crimper roller and tine cultivator for barley, crimper roller for vetch), offered the best termination effectiveness for both barley and vetch, with a termination rate of greater than or equal to 85%

Projection Neuron Circuits Resolved Using Correlative Array Tomography

Assessment of three-dimensional morphological structure and synaptic connectivity is essential for a comprehensive understanding of neural processes controlling behavior. Different microscopy approaches have been proposed based on light microcopy (LM), electron microscopy (EM), or a combination of both. Correlative array tomography (CAT) is a technique in which arrays of ultrathin serial sections are repeatedly stained with fluorescent antibodies against synaptic molecules and neurotransmitters and imaged with LM and EM (Micheva and Smith, 2007). The utility of this correlative approach is limited by the ability to preserve fluorescence and antigenicity on the one hand, and EM tissue ultrastructure on the other. We demonstrate tissue staining and fixation protocols and a workflow that yield an excellent compromise between these multimodal imaging constraints. We adapt CAT for the study of projection neurons between different vocal brain regions in the songbird. We inject fluorescent tracers of different colors into afferent and efferent areas of HVC in zebra finches. Fluorescence of some tracers is lost during tissue preparation but recovered using anti-dye antibodies. Synapses are identified in EM imagery based on their morphology and ultrastructure and classified into projection neuron type based on fluorescence signal. Our adaptation of array tomography, involving the use of fluorescent tracers and heavy-metal rich staining and embedding protocols for high membrane contrast in EM will be useful for research aimed at statistically describing connectivity between different projection neuron types and for elucidating how sensory signals are routed in the brain and transformed into a meaningful motor output

Correlative Microscopy of Densely Labeled Projection Neurons Using Neural Tracers

Three-dimensional morphological information about neural microcircuits is of high interest in neuroscience, but acquiring this information remains challenging. A promising new correlative technique for brain imaging is array tomography (Micheva and Smith, 2007), in which series of ultrathin brain sections are treated with fluorescent antibodies against neurotransmitters and synaptic proteins. Treated sections are repeatedly imaged in the fluorescence light microscope (FLM) and then in the electron microscope (EM). We explore a similar correlative imaging technique in which we differentially label distinct populations of projection neurons, the key routers of electrical signals in the brain. In songbirds, projection neurons can easily be labeled using neural tracers, because the vocal control areas are segregated into separate nuclei. We inject tracers into areas afferent and efferent to the main premotor area for vocal production, HVC, to retrogradely and anterogradely label different classes of projection neurons. We optimize tissue preparation protocols to achieve high fluorescence contrast in the FLM and good ultrastructure in the EM (using osmium tetroxide). Although tracer fluorescence is lost during EM preparation, we localize the tracer molecules after fixation and embedding by using fluorescent antibodies against them. We detect signals mainly in somata and dendrites, allowing us to classify synapses within a single ultrathin section as belonging to a particular type of projection neuron. The use of our method will be to provide statistical information about connectivity among different neuron classes, and to elucidate how signals in the brain are processed and routed among different areas