1,106 research outputs found
An integrated approach project for the revaluation of a traditional sourdough bread production chain
The influence of organic and conventional farming systems on the performance of a panel of old and modern Italian bread wheat varieties has been evaluated, with the aim to individuate an agronomic protocol suitable for the production of a sourdough bread traditionally prepared in a hill zone of Emilia-Romagna. The agronomic and technological characterisation of the wheat samples obtained in organic and conventional farming conditions has been done and the sensorial qualities of the sourdough bread obtained have been evaluated
Fractional Quantum Hall Effect in a Diluted Magnetic Semiconductor
We report the observation of the fractional quantum Hall effect in the lowest
Landau level of a two-dimensional electron system (2DES), residing in the
diluted magnetic semiconductor Cd(1-x)Mn(x)Te. The presence of magnetic
impurities results in a giant Zeeman splitting leading to an unusual ordering
of composite fermion Landau levels. In experiment, this results in an
unconventional opening and closing of fractional gaps around filling factor v =
3/2 as a function of an in-plane magnetic field, i.e. of the Zeeman energy. By
including the s-d exchange energy into the composite Landau level spectrum the
opening and closing of the gap at filling factor 5/3 can be modeled
quantitatively. The widely tunable spin-splitting in a diluted magnetic 2DES
provides a novel means to manipulate fractional states
Meta-analysis on the Effect of Mild Primary Hyperparathyroidism and Parathyroidectomy upon Arterial Stiffness
Context: Current data about the cardiovascular manifestations of mild primary hyperparathyroidism (pHPT) are often conflicting. Pulse wave velocity (PWV) is the gold standard for assessing aortic stiffness, and it predicts cardiovascular morbidity and mortality. Objective: Primary outcomes were to investigate if mild pHPT was associated with higher PWV and if parathyroidectomy (PTX) reduced PWV in mild pHPT. Secondary outcome was to investigate blood pressure changes after PTX. Methods: Sources were PubMed, Google Scholar, SCOPUS, Web of Science, and the Cochrane Library. Eligible studies included reports of PWV in patients with mild pHPT and controls, or in patients with mild pHPT before and after PTX. Two investigators independently identified eligible studies and extracted data. Pooled mean difference (MD) was the summary effect measure. Data were presented in forest plots with outlier and influential case diagnostics. Nine observational studies and one randomized clinical trial were selected, including 433 patients with mild pHPT, 171 of whom underwent PTX, and 407 controls. PWV was significantly higher in mild pHPT than in controls (MD = 1.18, 0.67 to 1.68, P <. 0001). Seven studies evaluated the effect of PTX on PWV. PTX significantly reduced PWV (MD =-0.48,-0.88 to-0.07, P =. 022). Conclusion: Aortic stiffness is increased in patients with mild pHPT, supporting the notion that mild pHPT is also associated with adverse cardiovascular manifestations. PTX significantly reduced arterial stiffness in mild pHPT, indicating that the benefit of PTX over cardiovascular manifestations should not be dismissed but it deserves further studies
CDKL5 expression is modulated during neuronal development and its subcellular distribution is tightly regulated by the C-terminal tail
Mutations in the human X-linked cyclin-dependent kinase-like 5 (CDKL5) gene have been identified in patients with Rett syndrome (RTT), West syndrome, and X-linked infantile spasms, sharing the common feature of mental retardation and early seizures. CDKL5 is a rather uncharacterized kinase, but its involvement in RTT seems to be explained by the fact that it works upstream of MeCP2, the main cause of Rett syndrome. To understand the role of this kinase for nervous system functions and to address if molecular mechanisms are involved in regulating its distribution and activity, we studied the ontogeny of CDKL5 expression in developing mouse brains by immunostaining and Western blotting. The expression profile of CDKL5 was compared with that of MeCP2. The two proteins share a general expression profile in the adult mouse brain, but CDKL5 levels appear to be highly modulated at the regional level. Its expression is strongly induced in early postnatal stages, and in the adult brain CDKL5 is present in mature neurons, but not in astroglia. Interestingly, the presence of CDKL5 in the cell nucleus varies at the regional level of the adult brain and is developmentally regulated. CDKL5 shuttles between the cytoplasm and the nucleus and the C-terminal tail is involved in localizing the protein to the cytoplasm in a mechanism depending on active nuclear export. Accordingly, Rett derivatives containing disease-causing truncations of the C terminus are constitutively nuclear, suggesting that they might act as gain of function mutations in this cellular compartment
Multistable Kuramoto splay states in a crystal of mode-locked laser pulses
We demonstrate the existence of a multiplicity of co-existing frequency combs
in a harmonically mode-locked laser that we link to the splay phases of the
Kuramoto model with short range interactions. These splay states are
multistable and the laser may wander between them under the influence of
stochastic forces. Consequently, the many pulses circulating in the cavity are
not necessarily coherent with each other. We show that this partially
disordered state for the phase of the optical field features regular train of
pulses in the field intensity, a state that we term an incoherent crystal of
optical pulses. We provide evidence that the notion of coherence should be
interpreted by comparing the duration of the measurement time with the Kramers'
escape time of each splay state. Our results are confirmed experimentally by
studying a passively mode-locked vertical external-cavity surface-emitting
laser.Comment: Main manuscript (5 pages + 5 figures) & Supplementary material (10
pages + 6 figures
Noise-induced broadening of a quantum-dash laser optical frequency comb
Single-section quantum dash semiconductor lasers have attracted much
attention as an integrated and simple platform for the generation of THz-wide
and flat optical frequency combs in the telecom C-band. In this work, we
present an experimental method allowing to increase the spectral width of the
laser comb by the injection of a broadband optical noise from an external
semiconductor optical amplifier that is spectrally overlapped with the quantum
dash laser comb. The noise injection induces an amplification of the side modes
of the laser comb which acquire a fixed phase relationship with the central
modes of the comb. We demonstrate a broadening of the laser comb by a factor of
two via this technique.Comment: 4 pages, 4 figure
Diagonally Neighbour Transitive Codes and Frequency Permutation Arrays
Constant composition codes have been proposed as suitable coding schemes to
solve the narrow band and impulse noise problems associated with powerline
communication. In particular, a certain class of constant composition codes
called frequency permutation arrays have been suggested as ideal, in some
sense, for these purposes. In this paper we characterise a family of neighbour
transitive codes in Hamming graphs in which frequency permutation arrays play a
central rode. We also classify all the permutation codes generated by groups in
this family
Aging and Vascular Disease: A Multidisciplinary Overview
Vascular aging, i.e., the deterioration of the structure and function of the arteries over the life course, predicts cardiovascular events and mortality. Vascular degeneration can be recognized before becoming clinically symptomatic; therefore, its assessment allows the early identification of individuals at risk. This opens the possibility of minimizing disease progression. To review these issues, a search was completed using PubMed, MEDLINE, and Google Scholar from 2000 to date. As a network of clinicians and scientists involved in vascular medicine, we here describe the structural and functional age-dependent alterations of the arteries, the clinical tools for an early diagnosis of vascular aging, and the cellular and molecular events implicated. It emerges that more studies are necessary to identify the best strategy to quantify vascular aging, and to design proper physical activity programs, nutritional and pharmacological strategies, as well as social interventions to prevent, delay, and eventually revert the disease
Temporal Localized Structures in mode-locked Vertical External-Cavity Surface-Emitting Lasers
Temporal Localized States (TLSs) are individually addressable structures
traveling in optical resonators. They can be used as bits of information and to
generate frequency combs with tunable spectral density. We show that a pair of
specially designed nonlinear mirrors, a 1/2 Vertical-Cavity Surface-Emitting
Laser and a Semiconductor Saturable Absorber, coupled in self-imaging
conditions, can lead to the generation of such TLSs. Our results indicate how a
conventional passive mode- locking scheme can be adapted to provide a robust
and simple system emitting TLSs and it paves the way towards the observation of
three dimensions confined states, the so-called light bullets.Comment: submission to Optics Letter
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