108 research outputs found
Impact of Decoherence on Internal State Cooling using Optical Frequency Combs
We discuss femtosecond Raman type techniques to control molecular vibrations,
which can be implemented for internal state cooling from Feshbach states with
the use of optical frequency combs with and without modulation. The technique
makes use of multiple two-photon resonances induced by optical frequencies
present in the comb. It provides us with a useful tool to study the details of
molecular dynamics at ultracold temperatures. In our theoretical model we take
into account decoherence in the form of spontaneous emission and collisional
dephasing in order to ascertain an accurate model of the population transfer in
the three-level system. We analyze the effects of odd and even chirps of the
optical frequency comb in the form of sine and cosine functions on the
population transfer. We compare the effects of these chirps to the results
attained with the standard optical frequency comb to see if they increase the
population transfer to the final deeply bound state in the presence of
decoherence. We also analyze the inherent phase relation that takes place owing
to collisional dephasing between molecules in each of the states. This ability
to control the rovibrational states of a molecule with an optical frequency
comb enables us to create a deeply bound ultracold polar molecules from the
Feshbach state.Comment: 10 pages, 6 figure
Phenotypical and biochemical characterization of tomato plants treated with triacontanol
Biostimulants are heterogeneous products designed to support plant development and to improve the yield and quality of crops. Here, we focused on the effects of triacontanol, a promising biostimulant found in cuticle waxes, on tomato growth and productivity. We examined various phenological traits related to vegetative growth, flowering and fruit yield, the metabolic profile of fruits, and the response of triacontanol-treated plants to salt stress. Additionally, a proteomic analysis was conducted to clarify the molecular mechanisms underlying triacontanol action. Triacontanol application induced advanced and increased blooming without affecting plant growth. Biochemical analyses of fruits showed minimal changes in nutritional properties. The treatment also increased the germination rate of seeds by altering hormone homeostasis and reduced salt stress-induced damage. Proteomics analysis of leaves revealed that triacontanol increased the abundance of proteins related to development and abiotic stress, while down-regulating proteins involved in biotic stress resistance. The proteome of the fruits was not significantly affected by triacontanol, confirming that biostimulation did not alter the nutritional properties of fruits. Overall, our findings provide evidence of the effects of triacontanol on growth, development, and stress tolerance, shedding light on its mechanism of action and providing new insights into its potential in agricultural practices
Enhanced light trapping using plasmonic nanoparticles
International audiencePlasmonics is a new light trapping method used in photovoltaic (PV) solar cells. A significant enhancement of the scattered and absorbed incident light due to the use of silver nanoparticles (Ag-NPs) was observed, which yield to the exaltation of the electromagnetic field in the vicinity of these NPs. In this context, we investigate optically and morphologically the effect of the NPs size dependence on the localized surface plasmon resonance. Extinction, absorption and scattering cross sections are calculated using Mie theory
The Epidemiology of Hypoparathyroidism in Italy: An 8-Year Register-Based Study
Hypoparathyroidism is a rare endocrine disorder,
but few studies have focused on the epidemiology and
hospital management of the disease and none has been
performed in Italy. We investigated the prevalence of dif-
ferent forms of hypoparathyroidism among hospitalized
patients in Italy during an 8-year period. This study is
designed as a retrospective register-based study. We
retrieved data from the ââRecord of Hospital Dischargeââ
(SDO) of the Italian Health Ministry, from the year 2006 to
2013
and
analyzed
the
codes
corresponding
to
hypoparathyroidism-related
diagnoses.
The
inpatient
prevalence of the disease was also calculated after
excluding repeated hospitalizations. Overall, 27,692 hos-
pitalization episodes for hypoparathyroidism were identi-
fied during the entire period (72.2% in women and 27.8%
in men; mean age 49.5
±
22.9 years). The mean length of
stay was 7.4
±
9.8 days (25.9% of the episodes requiring
less than 3 days of stay). The mean hospitalization rate for
hypoparathyroidism was 5.9/100,000 inhabitants per year
and there was a significant decrease during the period of
2006â2013 (
p
\
0.0001). The mean hospitalization rate for
postsurgical hypoparathyroidism was 1.4/100,000 inhabi-
tants per year and the trend showed a significant reduction during the years (
p
\
0.0001). The mean prevalence of
hypoparathyroidism among inpatients was 5.3/100,000
inhabitants per year, and there was a significant decrease
over the years (
p
\
0.0001). Hypoparathyroidism, partic-
ularly the postsurgical form of the disease, is not an
uncommon condition among hospitalized patients in Italy.
We observed a tendency to a decrease in the frequency of
hospitalization during the period 2006â201
Construction and commissioning of a technological prototype of a high-granularity semi-digital hadronic calorimeter
A large prototype of 1.3m3 was designed and built as a demonstrator of the
semi-digital hadronic calorimeter (SDHCAL) concept proposed for the future ILC
experiments. The prototype is a sampling hadronic calorimeter of 48 units. Each
unit is built of an active layer made of 1m2 Glass Resistive Plate
Chamber(GRPC) detector placed inside a cassette whose walls are made of
stainless steel. The cassette contains also the electronics used to read out
the GRPC detector. The lateral granularity of the active layer is provided by
the electronics pick-up pads of 1cm2 each. The cassettes are inserted into a
self-supporting mechanical structure built also of stainless steel plates
which, with the cassettes walls, play the role of the absorber. The prototype
was designed to be very compact and important efforts were made to minimize the
number of services cables to optimize the efficiency of the Particle Flow
Algorithm techniques to be used in the future ILC experiments. The different
components of the SDHCAL prototype were studied individually and strict
criteria were applied for the final selection of these components. Basic
calibration procedures were performed after the prototype assembling. The
prototype is the first of a series of new-generation detectors equipped with a
power-pulsing mode intended to reduce the power consumption of this highly
granular detector. A dedicated acquisition system was developed to deal with
the output of more than 440000 electronics channels in both trigger and
triggerless modes. After its completion in 2011, the prototype was commissioned
using cosmic rays and particles beams at CERN.Comment: 49 pages, 41 figure
Performance of Glass Resistive Plate Chambers for a high granularity semi-digital calorimeter
A new design of highly granular hadronic calorimeter using Glass Resistive
Plate Chambers (GRPCs) with embedded electronics has been proposed for the
future International Linear Collider (ILC) experiments. It features a 2-bit
threshold semi-digital read-out. Several GRPC prototypes with their electronics
have been successfully built and tested in pion beams. The design of these
detectors is presented along with the test results on efficiency, pad
multiplicity, stability and reproducibility.Comment: 16 pages, 15 figure
Emulsion sheet doublets as interface trackers for the OPERA experiment
New methods for efficient and unambiguous interconnection between electronic
counters and target units based on nuclear photographic emulsion films have
been developed. The application to the OPERA experiment, that aims at detecting
oscillations between mu neutrino and tau neutrino in the CNGS neutrino beam, is
reported in this paper. In order to reduce background due to latent tracks
collected before installation in the detector, on-site large-scale treatments
of the emulsions ("refreshing") have been applied. Changeable Sheet (CSd)
packages, each made of a doublet of emulsion films, have been designed,
assembled and coupled to the OPERA target units ("ECC bricks"). A device has
been built to print X-ray spots for accurate interconnection both within the
CSd and between the CSd and the related ECC brick. Sample emulsion films have
been extensively scanned with state-of-the-art automated optical microscopes.
Efficient track-matching and powerful background rejection have been achieved
in tests with electronically tagged penetrating muons. Further improvement of
in-doublet film alignment was obtained by matching the pattern of low-energy
electron tracks. The commissioning of the overall OPERA alignment procedure is
in progress.Comment: 19 pages, 19 figure
First events from the CNGS neutrino beam detected in the OPERA experiment
The OPERA neutrino detector at the underground Gran Sasso Laboratory (LNGS)
was designed to perform the first detection of neutrino oscillations in
appearance mode, through the study of nu_mu to nu_tau oscillations. The
apparatus consists of a lead/emulsion-film target complemented by electronic
detectors. It is placed in the high-energy, long-baseline CERN to LNGS beam
(CNGS) 730 km away from the neutrino source. In August 2006 a first run with
CNGS neutrinos was successfully conducted. A first sample of neutrino events
was collected, statistically consistent with the integrated beam intensity.
After a brief description of the beam and of the various sub-detectors, we
report on the achievement of this milestone, presenting the first data and some
analysis results.Comment: Submitted to the New Journal of Physic
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