We present a novel method to perform a direct T (time reversal) symmetry test in the neutral kaon system, independent of any CP and/or CPT symmetry tests. This is based on the comparison of suitable ...transition probabilities, where the required interchange of in ↔ out states for a given process is obtained exploiting the Einstein–Podolski–Rosen correlations of neutral kaon pairs produced at a ϕ-factory. In the time distribution between the two decays, we compare a reference transition like the one defined by the time-ordered decays (ℓ−,ππ) with the T-conjugated one defined by (3π0,ℓ+). With the use of this and other T-conjugated comparisons, the KLOE-2 experiment at DAΦNE could make a statistically significant test.
ELOVL5 Mutations Cause Spinocerebellar Ataxia 38 Di Gregorio, Eleonora; Borroni, Barbara; Giorgio, Elisa ...
American journal of human genetics,
08/2014, Letnik:
95, Številka:
2
Journal Article
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Spinocerebellar ataxias (SCAs) are a heterogeneous group of autosomal-dominant neurodegenerative disorders involving the cerebellum and 23 different genes. We mapped SCA38 to a 56 Mb region on ...chromosome 6p in a SCA-affected Italian family by whole-genome linkage analysis. Targeted resequencing identified a single missense mutation (c.689G>T p.Gly230Val) in ELOVL5. Mutation screening of 456 independent SCA-affected individuals identified the same mutation in two further unrelated Italian families. Haplotyping showed that at least two of the three families shared a common ancestor. One further missense variant (c.214C>G p.Leu72Val) was found in a French family. Both missense changes affect conserved amino acids, are predicted to be damaging by multiple bioinformatics tools, and were not identified in ethnically matched controls or within variant databases. ELOVL5 encodes an elongase involved in the synthesis of polyunsaturated fatty acids of the ω3 and ω6 series. Arachidonic acid and docosahexaenoic acid, two final products of the enzyme, were reduced in the serum of affected individuals. Immunohistochemistry on control mice and human brain demonstrated high levels in Purkinje cells. In transfection experiments, subcellular localization of altered ELOVL5 showed a perinuclear distribution with a signal increase in the Golgi compartment, whereas the wild-type showed a widespread signal in the endoplasmic reticulum. SCA38 and SCA34 are examples of SCAs due to mutations in elongase-encoding genes, emphasizing the importance of fatty-acid metabolism in neurological diseases.
We present a new limit on the production of a light dark-force mediator with the KLOE detector at DAΦNE. This boson, called U, has been searched for in the decay ϕ→ηU, U→e+e−, analyzing the decay ...η→π0π0π0 in a data sample of 1.7 fb−1. No structures are observed in the e+e− invariant mass distribution over the background. This search is combined with a previous result obtained from the decay η→π+π−π0, increasing the sensitivity. We set an upper limit at 90% C.L. on the ratio between the U boson coupling constant and the fine structure constant of α′/α<1.7×10−5 for 30<MU<400 MeV and α′/α⩽8×10−6 for the sub-region 50<MU<210 MeV. This result assumes the Vector Meson Dominance expectations for the ϕηγ⁎ transition form factor. The dependence of this limit on the transition form factor has also been studied.
Neurokinin B (NKB) and its receptor (NK3R) are coexpressed with kisspeptin, Dynorphin A (Dyn), and their receptors G-protein-coupled receptor-54 (GPR54) and κ-opioid receptor (KOR), respectively ...within kisspeptin/NKB/Dyn (KNDy) neurons in the hypothalamic arcuate nucleus (ARC), the proposed site of the GnRH pulse generator. Much previous research has employed intracerebroventricular (icv) administration of KNDy agonists and antagonists to address the functions of KNDy neurons. We performed a series of in vivo neuropharmacological experiments aiming to determine the role of NKB/NK3R signaling in modulating the GnRH pulse generator and elucidate the interaction between KNDy neuropeptide signaling systems, targeting our interventions to ARC KNDy neurons. First, we investigated the effect of intra-ARC administration of the selective NK3R agonist, senktide, on pulsatile LH secretion using a frequent automated serial sampling method to obtain blood samples from freely moving ovariectomized 17β-estradiol-replaced rats. Our results show that senktide suppresses LH pulses in a dose-dependent manner. Intra-ARC administration of U50488, a selective KOR agonist, also caused a dose-dependent, albeit more modest, decrease in LH pulse frequency. Thus we tested the hypothesis that Dyn/KOR signaling localized to the ARC mediates the senktide-induced suppression of the LH pulse by profiling pulsatile LH secretion in response to senktide in rats pretreated with nor-binaltorphimine, a selective KOR antagonist. We show that nor-binaltorphimine blocks the senktide-induced suppression of pulsatile LH secretion but does not affect LH pulse frequency per se. In order to address the effects of acute activation of ARC NK3R, we quantified (using quantitative RT-PCR) changes in mRNA levels of KNDy-associated genes in hypothalamic micropunches following intra-ARC administration of senktide. Senktide down-regulated expression of genes encoding GnRH and GPR54 (GNRH1 and Kiss1r, respectively), but did not affect the expression of Kiss1 (which encodes kisspeptin). We conclude that NKB suppresses the GnRH pulse generator in a KOR-dependent fashion and regulates gene expression in GnRH neurons.
Using 1.63 fb−1 of integrated luminosity collected by the KLOE experiment about \({\rm{7}}\times {{\rm{10}}}^{4}\,{{\rm{K}}}_{{\rm{S}}}\to \pi ev\) decays have been reconstructed. The measured value ...of the charge asymmetry for this decay is AS = (−4.9 ± 5.7stat ± 2.6 syst ) x 10−3 which is almost twice more precise than the previous KLOE result. The combination of these two measurements gives AS = (−3.8 ± 5.0 stat ±2.6syst) x 10−3 and, together with the asymmetry of the KL semileptonic decay, provides significant tests of the CPT symmetry. The obtained results are in agreement with CPT invariance.
A
bstract
In this paper we present a novel CPT symmetry test in the neutral kaon system based, for the first time, on the direct comparison of the probabilities of a transition and its CPT reverse. ...The required interchange of
in
↔
out
states for a given process is obtained exploiting the Einstein-Podolsky-Rosen correlations of neutral kaon pairs produced at a
ϕ
-factory. The observable quantities have been constructed by selecting the two semileptonic decays for flavour tag, the
ππ
and 3
π
0
decays for CP tag and the time orderings of the decay pairs. The interpretation in terms of the standard Weisskopf-Wigner approach to this system, directly connects CPT violation in these observables to the violating ℜδ parameter in the mass matrix of
K
0
−
K
¯
0
, a genuine CPT violating effect independent of ΔΓ and not requiring the decay as an essential ingredient.
Possible spurious effects induced by CP violation in the decay and/or a violation of the Δ
S
= Δ
Q
rule have been shown to be well under control. The proposed test is thus fully robust, and might shed light on possible new CPT violating mechanisms, or further improve the precision of the present experimental limits. It could be implemented at the DAΦNE facility in Frascati, where the KLOE-2 experiment might reach a statistical sensitivity of
O
(10
−3
) on the newly proposed observable quantities.
A new kind of CPT test for transitions in the neutral kaon system is presented, where the exchange of in and out states (and CP conjugation), required for a direct and genuine CPT test, is performed ...exploiting the entanglement of the kaon pair produced at a φ-factory. Using this method it would be possible for the first time to directly test the CPT symmetry in transition processes between meson states, rather than comparing masses, lifetimes, or other intrinsic properties of particle and anti-particle states. The proposed test in the neutral kaon system is very clean and fully robust, and might shed light on possible new CPT violating mechanisms, or further improve the precision of the present experimental limits. It could be implemented at the DAΦNE facility in Frascati, where the KLOE-2 experiment can reach a statistical sensitivity of ?CDATA ${\cal O}({10^{ - 3}})$ ?> O ( 10 − 3 ) on the newly proposed observable quantities.
A
bstract
The ratio
R
= Γ(
K
S
→ πeν
)
/
Γ(
K
S
→ π
+
π
−
) has been measured with a sample of 300 million
K
S
mesons produced in
ϕ → K
L
K
S
decays recorded by the KLOE experiment at the DAΦNE
e
+
e
...−
collider.
K
S
→ πeν
events are selected by a boosted decision tree built with kinematic variables and time-of-flight measurements. Data control samples of
K
L
→ πeν
decays are used to evaluate signal selection efficiencies. With 49647
±
316 signal events we measure
R
= (1
.
0421
±
0
.
0066
stat
±
0
.
0075
syst
)
×
10
−
3
. The combination with our previous measurement gives
R
= (1
.
0338
±
0
.
0054
stat
±
0
.
0064
syst
)
×
10
−
3
. From this value we derive the branching fraction
B
(
K
S
→ πeν
) = (7
.
153
±
0
.
037
stat
±
0
.
044
syst
)
×
10
−
4
and
f
+
(0)
|V
us
|
= 0
.
2170
±
0
.
009.
Synthetic aperture radar (SAR) systems can generate microwave images by using different acquisition modes: stripmap, spotlight, scanSAR, and the more recently developed sliding spotlight and Terrain ...Observation by Progressive Scans (TOPSAR). The proper mode to be used is chosen according to the desired spatial resolution and coverage. In this paper, we present a unified formulation able to express raw signals of all acquisition modes. This formulation is then employed to show that both sliding spotlight and TOPSAR raw signal simulation of extended scenes can be achieved by using an improved version of the approach previously proposed by some of the authors for the sliding spotlight case. This approach implies a 1-D range Fourier-domain processing, followed by 1-D azimuth time-domain integration, and it can also precisely account for sensor trajectory deviations for any acquisition mode. Effectiveness of the proposed simulation scheme is assessed by using numerical examples. Results show that its computational load is much lower than the one of the time-domain approaches, and the obtained raw signals are in very good agreement with the exact ones. Finally, examples of simulations of SAR signals relative to extended, both canonical and realistic, scenes are also reported.
Background
Dysphagia in the elderly, known as presbydysphagia, has become a relevant public health problem in several countries. Swallowing disorders may be a consequence of different neurological ...disorders (secondary presbydysphagia) or the expression of the aging process itself (primary presbydysphagia). We aimed to test the therapeutic potential of two different non‐invasive brain stimulation (NIBS) techniques in subjects with primary or secondary presbydysphagia.
Methods
A blinded randomized controlled trial with crossover design was carried out in 42 patients, randomly assigned to anodal transcranial direct current stimulation (tDCS) or intermittent theta‐burst stimulation (TBS) group. Both tDCS and TBS were applied for 5 consecutive days over the right swallowing motor cortex. The swallowing function was assessed before and 1 and 3 months after the stimulation using the Dysphagia Outcome and Severity Scale (DOSS), scored based on clinical assessment and fiberoptic endoscopic evaluation of swallowing. An electrophysiological method was also applied to evaluate changes in the reproducibility of the swallowing behavior.
Key Results
Both real tDCS and TBS had beneficial effects on the swallowing function in patients with primary and secondary presbydysphagia. Anodal tDCS resulted in an improvement of 0.5 points in DOSS at 1‐month follow‐up (P = .014), whereas intermittent TBS induced an increase of 0.7 and 0.6 points at 1‐ and 3‐month follow‐up evaluations, respectively (P = .0001 and P = .005, respectively). Reproducibility of both the oral and pharyngeal phases of swallowing significantly increased at 1‐month follow‐up.
Conclusions and Inferences
Our results suggest that non‐invasive cortical stimulation may be useful for dysphagia recovery in elderly patients.
Both anodal tDCS and intermittent TBS ameliorate the swallowing function in elderly patients with dysphagia, with effects lasting up to 1 month from the end of the stimulation period for tDCS, and 3 months for TBS. Prevalence of oropharyngeal dysphagia is huge and in alarming growth in the elderly population, both with or without neurological disorders, thus optimization of treatment strategies for swallowing disturbances is mandatory in view of the high mortality associated with this symptom.
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