The aim of the present study was to evaluate the different feeding frequencies on the performance, hematology profile, daily rhythms of glucose and activities digestive enzymes for juvenile ...Lophiosilurus alexandri. Feeding frequency did not affect survival, final weight, daily weight gain (P > .05). Glucose showed a daily rhythmic variation, with the acrophase in the group F2 located at Zeitgeber Time (ZT) 12.51 h and at ZT 13.33 h in the group F5. The daily rhythms in digestive enzymes were also affected, especially chymotrypsin, whose activity was twofold higher in F5 than F2. Food ratio divided into a higher frequency along the day induces an increase in acid protease and chymotrypsin activities. Different feeding frequencies can influence hematology profile, daily rhythms of glucose and activities digestive enzymes. The production of juvenile L. alexandri can be successfully carried out adopting a feeding frequency of twice a day.
Effect of environmental color on learning of Nile tilapia Torres, Isabela F. Araújo; Ferreira, Angélica da Silva; de Souza e Silva, Walisson ...
Applied animal behaviour science,
December 2018, 2018-12-00, 20181201, Letnik:
209
Journal Article
Recenzirano
•Environmental color may interfere with performance in learning tasks.•Black and green environments are the most suitable for maintenance and learning test.•Blue environment negatively impact ...individual performance in learning test.
This study investigates the effects of environmental color on learning capacity of Nile tilapia, Oreochromis niloticus. Eighty-four tilapia (12.81 ± 0.38 cm; 35.98 ± 8.33 g), were separated into six groups of fourteen and housed in blue, green and black tanks. The fish were acclimatized to their respective colored environment for 15 days. Learning tests were performed using T-mazes color-matched to the respective fish tank colors for 15 days. The fish were then tested in T-mazes of different colors from their tanks for another 5 days. The learning task involved exploring the maze in search of a reward (feed pellets) and associating a visual marker with the reward. Results showed that in color-matched mazes, the fish in black and green mazes required eleven days to learn the task (p < 0.0001), while those in the blue maze failed to learn the task (p = 0.101). All color changes affected fish performance at learning the task (blue p = 0.101; black and green p < 0.0001). Our results suggest that environmental color influences learning, with black and green environments being to be the most suitable for both maintenance and learning by Nile tilapia.
The CMS experiment, located at the Large Hadron Collider (LHC) in CERN, has a redundant muon system composed by three different gaseous detector technologies: Cathode Strip Chambers (in the forward ...regions), Drift Tubes (in the central region), and Resistive Plate Chambers (both its central and forward regions). All three are used for muon reconstruction and triggering. The CMS RPC system confers robustness and redundancy to the muon trigger. The RPC system operation in the challenging background and pileup conditions of the LHC environment is presented. The RPC system provides information to all muon track finders and thus contributing to both muon trigger and reconstruction. The summary of the detector performance results obtained with proton-proton collision at s=13 TeV during 2016 and 2017 data taking have been presented. The stability of the system is presented in terms of efficiency and cluster size vs time and increasing instantaneous luminosity. Data-driven predictions about the expected performance during High Luminosity LHC (HL-LHC) stage have been reported.
Abstract
The expected radiation background in the CMS RPC system has been studied using the MC prediction with the CMS FLUKA simulation of the detector and the cavern. The MC geometry used in the ...analysis describes very accurately the present RPC system but still does not include the complete description of the RPC upgrade region with pseudorapidity 1.9 < |η| < 2.4. Present results will be updated with the final geometry description, once it is available. The radiation background has been studied in terms of expected particle rates, absorbed dose and fluence. Two High Luminosity LHC (HL-LHC) scenarios have been investigated — after collecting 3000 and 4000 fb
-1
. Estimations with safety factor of 3 have been considered, as well.
High Rate RPC detector for LHC Lagarde, F.; Fagot, A.; Gul, M. ...
Journal of instrumentation,
10/2019, Letnik:
14, Številka:
10
Journal Article
Recenzirano
Odprti dostop
The High Luminosity LHC (HL-LHC) phase is designed to increase by an order of magnitude the amount of data to be collected by the LHC experiments. The foreseen gradual increase of the instantaneous ...luminosity of up to more than twice its nominal value of 10×1034cm-1s-2 during Phase I and Phase II of the LHC running, presents special challenges for the experiments. The region with high pseudo rapidity (η) region of the forward muon spectrometer (2.4>|η|>1.9) is not equipped with RPC stations. The increase of the expected particles rate up to 2 kHz cm-2 (including a safety factor 3) motivates the installation of RPC chambers to guarantee redundancy with the CSC chambers already present. The current CMS RPC technology cannot sustain the expected background level. A new generation of Glass-RPC (GRPC) using low-resistivity glass was proposed to equip the two most far away of the four high η muon stations of CMS. In their single-gap version they can stand rates of few kHz cm-2. Their time precision of about 1 ns can allow to reduce the noise contribution leading to an improvement of the trigger rate. The proposed design for large size chambers is examined and some preliminary results obtained during beam tests at Gamma Irradiation Facility (GIF++) and Super Proton Synchrotron (SPS) at CERN are shown. They were performed to validate the capability of such detectors to support high irradiation environment with limited consequence on their efficiency.
RPC upgrade project for CMS Phase II Pedraza-Morales, M.I.; Fagot, A.; Gul, M. ...
Journal of instrumentation,
05/2020, Letnik:
15, Številka:
5
Journal Article
Recenzirano
Odprti dostop
The Muon Upgrade Phase II of the Compact Muon Solenoid (CMS) aims to guarantee the optimal conditions of the present system and extend the η coverage to ensure a reliable system for the High ...Luminosity Large Hadron Collider (HL-LHC) period. The Resistive Plate Chambers (RPCs) system will upgrade the off-detector electronics (called link system) of the chambers currently installed chambers and place improved RPCs (iRPCs) to cover the high pseudo−rapidity region, a challenging region for muon reconstruction in terms of background and momentum resolution. In order to find the best option for the iRPCs, an R&D program for new detectors was performed and real size prototypes have been tested in the Gamma Irradiation Facility (GIF++) at CERN. The results indicated that the technology suitable for the high background conditions is based on High Pressure Laminate (HPL) double-gap RPC. The RPC Upgrade Phase II program is planned to be ready after the Long Shutdown 3 (LS3).
The present Compact Muon Solenoid Resistive Plate Chambers system has been worked efficiently during Run I and Run II of data taking period (Shah et al., 2020) 1. In the coming years of operation ...with the High Luminosity LHC (HL-LHC), the expected rate and integrated charge are expected to be about 600 Hz/cm2 and 840 mC/cm2, respectively (including a safety factor of three). Therefore, the HL-LHC phase will be a challenge for the RPC system since the expected operating conditions are much harsher than those for which the detectors have been designed, and could introduce non-recoverable aging effects which can alter the detector properties. A longevity test has been started at the CERN Gamma Irradiation Facility to estimate the impact of HL-LHC conditions on the RPC detector performance in order to determine whether the RPC system will survive the harsher background conditions expected at HL-LHC. The latest results of the irradiation test will be presented.
In the next decades, the Large Hadron Collider (LHC) will run at very high luminosity (HL-LHC) 5×1034 cm−2s−1, factor five more than the nominal LHC luminosity. During this period the CMS RPC system ...will be subjected to high background rates which could affect the performance by inducing aging effects. A dedicated longevity program to qualify the present RPC system for the HL-LHC running period is ongoing. At the CERN Gamma Irradiation Facility (GIF++) four RPC detectors, from the spare production, are exposed to an intense gamma radiation for a dose equivalent to the one expected at the HL-LHC . The main detector parameters are under monitoring as a function of the integrated charge and the performance is studied with a muon beam. Preliminary results of the study after having collected ≈ 34% of the expected integrated charge will be presented.
Four double-gap CMS resistive plate chambers are being tested at the CERN Gamma Irradiation Facility to determine the performance and aging effects at the expected conditions of the High ...Luminosity-Large Hadron Collider. Results up to an integrated charge of 290 millicoulomb/cm2 are reported.
We measure the efficiency of CMS Resistive Plate Chamber (RPC) detectors in proton-proton collisions at the centre-of-mass energy of 13 TeV using the tag-and-probe method. A muon from a Z0 boson ...decay is selected as a probe of efficiency measurement, reconstructed using the CMS inner tracker and the rest of CMS muon systems. The overall efficiency of CMS RPC chambers during the 2016–2017 collision runs is measured to be more than 96% for the nominal RPC chambers.
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