Sensory perception modulates health and aging across taxa. Understanding the nature of relevant cues and the mechanisms underlying their action may lead to novel interventions that improve the length ...and quality of life. We found that in the vinegar fly, Drosophila melanogaster, exposure to dead conspecifics in the environment induced cues that were aversive to other flies, modulated physiology, and impaired longevity. The effects of exposure to dead conspecifics on aversiveness and lifespan required visual and olfactory function in the exposed flies. Furthermore, the sight of dead flies was sufficient to produce aversive cues and to induce changes in the head metabolome. Genetic and pharmacologic attenuation of serotonergic signaling eliminated the effects of exposure on aversiveness and lifespan. Our results indicate that Drosophila have an ability to perceive dead conspecifics in their environment and suggest conserved mechanistic links between neural state, health, and aging; the roots of which might be unearthed using invertebrate model systems.
A low-resistivity RPC for the ALICE dimuon arm Arnaldi, R; Baldit, A; Barret, V ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2000, Letnik:
451, Številka:
2
Journal Article
Recenzirano
In view of ALICE, the dedicated Heavy-Ion Experiment at LHC, a Resistive Plate Chamber (RPC) with electrodes made of low-resistivity bakelite (
ρ≃3.5×10
9
Ω
cm
) has been tested at the CERN SPS both ...in streamer and in avalanche mode. The chamber has shown a stable behaviour and excellent rate capability: its efficiency is better than 95% for local particle fluxes of about 1 and 10 kHz/cm
2 for operation in streamer and in avalanche mode, respectively. The cluster size and the time resolution have also been measured for both modes of operation.
Quartz-fiber calorimeters have been the object of an intense and fruitful work of research and development in the last few years. In this paper we report about the first application of this technique ...in an experiment. Namely, we describe the design and performance of the Zero-Degree Calorimeter (ZDC) used in NA50, a heavy-ion experiment at CERN SPS aiming to detect the formation of quark-gluon plasma in Pb–Pb collisions at 158
AGeV by studying the production of the charmonia states J/ψ and ψ′. The unique properties of the quartz-fiber calorimeters turn out to be well suited to match the specific requirements of this experiment that operates at beam intensity of about 10
7
Pb-ion/s: radiation hardness (up to a few Grads), short duration of the signal (∼10
ns), spatial resolution of a few hundreds of μm, small size of the detector (5×5×65
cm
3) and energy resolution adequate for providing a precise measurement of the collision centrality.
The trigger setup of the dimuon arm of ALICE, the dedicated Heavy-Ion Experiment at LHC, is based on Resistive Plate Chambers (RPCs). This gaseous detector can be operated either in streamer or in ...avalanche mode, each mode having its own advantages and drawbacks. Using conventional discrimination techniques, like single threshold or constant fraction discriminator, the time resolution is better in avalanche mode (commonly
1
ns
) unless the RPC is operated in streamer mode at quite high running voltages which is not suitable. Since we propose to operate the RPCs in streamer mode in ALICE, we have studied a new discrimination technique in order to improve the time resolution in this mode. With this method, a comparable timing quality as one of the avalanche modes is typically obtained, as soon as the applied voltage is sufficient for the RPC to reach the full efficiency. This is an important progress not only for the ALICE trigger but also because the RPC detector is widely used in streamer mode.
From September 1989 through July 1991, before commercial availability, Survanta (beractant intratracheal suspension), a modified bovine-derived surfactant used for prevention and treatment of ...neonatal respiratory distress syndrome, was made available to 231 neonatal intensive care units in the United States and Canada under a Treatment Investigational New Drug protocol. Results of this open clinical experience are reported. Investigators could give one dose of Survanta soon after birth to neonates weighing 600 to 1250 g (prevention strategy). Neonates weighing 600 to 1750 g who were not treated at birth could begin Survanta therapy if respiratory distress syndrome developed within 8 hours of birth (rescue strategy). All neonates could receive up to three more doses over the first 48 hours of life at minimum intervals of 6 hours if they met retreatment criteria. Qualifications for enrollment closely matched those used in previous randomized controlled clinical trials. This report includes results from 8168 neonates who completed the study. Treatment Investigational New Drug rates for intracranial hemorrhage, patent ductus arteriosus, pulmonary hemorrhage, pulmonary air leaks, bronchopulmonary dysplasia, death or bronchopulmonary dysplasia, pulmonary interstitial emphysema, pretreatment sepsis, and posttreatment sepsis were less than for treated neonates in the controlled trials and survival was equivalent across studies. Problems with treatment administration were reported with 30.4% of doses, while adverse events were reported in 0.5% of neonates. The results of the Treatment Investigational New Drug protocol revealed no new safety concerns associated with the widespread use of Survanta and confirmed the safety profile established in earlier controlled trials.
Quartz fiber calorimetry Gorodetzky, P; Lazic, D; Anzivino, G ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/1995, Letnik:
361, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The fundamentals of a new electromagnetic and hadronic sampling calorimetry based on the detection of Cherenkov light generated in quartz optical fibers are presented. Optical fibers transport light ...only in a selected angular range which results in a non-obvious and absolutely unique characteristic for this new technique: showers of very narrow visible energy. In addition, the technique is characterized by radiation resistance measured in Gigarads and nanosecond signal duration. Combined, these properties make quartz fiber calorimetry a very promising technique for high intensity heavy ion experiments and for the high pseudorapidity regions of high intensity collider experiments. The results of beam tests and simulations are used to illustrate the basic properties and peculiar characteristics of this recent development.
Quartz fiber ZDCs at CERN SPS and LHC Arnaldi, R; Chiavassa, E; Dellacasa, G ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/1998, Letnik:
409, Številka:
1-3
Journal Article
Recenzirano
A quartz fiber zero degree calorimeter (ZDC) is operating in the NA50 experiment at CERN SPS since its first lead ion run in November 1994. This unusually small detector (5×5×65cm3) is a spaghetti ...calorimeter with quartz optical fibers embedded in tantalum slabs. The ZDC performances are presented with special emphasis on the 1996 lead ion run results. The plans for ALICE ZDCs at LHC are also presented.
Quartz-fiber calorimeters have been object of an intense and fruitful work of research and developement in the very last years. In this paper, together with the performance of the quartz-fiber ...zero-degree calorimeter used in the NA50 experiment at, CERN SPS, we also present the design of the quartz-fiber calorimeters for ALICE, the dedicated heavy-ion experiment at LHC.
A dedicated front-end electronics has been developed for the trigger chambers of the ALICE muon spectrometer under construction at the future LHC at CERN. This trigger detector is based on RPCs ...(Resistive Plate Chambers) working in streamer mode. The number of electronics channels (about 21000) and the fact that RPC signals have specific characteristics have led to the design of an 8 channel front-end ASIC using a new discrimination technique. The principle of the ASIC is described and the radiation hardness is discussed. Special emphasis is put on production characteristics of about 4000 ASICs.
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