A
bstract
A comprehensive set of azimuthal single-spin and double-spin asymmetries in semi-inclusive leptoproduction of pions, charged kaons, protons, and antiprotons from transversely polarized ...protons is presented. These asymmetries include the previously published HERMES results on Collins and Sivers asymmetries, the analysis of which has been extended to include protons and antiprotons and also to an extraction in a three-dimensional kinematic binning and enlarged phase space. They are complemented by corresponding results for the remaining four single-spin and four double-spin asymmetries allowed in the one-photon-exchange approximation of the semi-inclusive deep-inelastic scattering process for target-polarization orientation perpendicular to the direction of the incoming lepton beam. Among those results, significant non-vanishing cos (
ϕ−ϕ
S
) modulations provide evidence for a sizable worm-gear (II) distribution,
g
1
T
q
x
p
T
2
. Most of the other modulations are found to be consistent with zero with the notable exception of large sin (
ϕ
S
) modulations for charged pions and
K
+
.
A survey was conducted on two Brazilian chocolate manufacturing companies (A and B) to investigate/determine Enterobacteriaceae, coliforms and Salmonella contamination. Samples of different chocolate ...types, processed cocoa-based ingredients, manufacturing environment, and workers' hand surfaces were analyzed. Salmonella and Escherichia coli were not detected. However, in 25.8% of the chocolate samples, Enterobacteriaceae were isolated while total coliforms were detected in 13.3%. Among the processed cocoa-based ingredients, two samples of cocoa liquor showed contamination by Enterobacteriaceae and total coliforms, and in one sample thermotolerant coliforms were also recovered. For equipment and utensils, Enterobacteriaceae were isolated in around 25.4% of the samples, whereas total coliforms were detected in 10.2%. Moreover, in company A 14.3% of manufacturing environment samples were contaminated by thermotolerant coliforms. The food handlers from both companies showed a high percentage of Enterobacteriaceae contamination on their hands. The results showed that the manufacturing environment including food handlers was considered the most likely Enterobacteriaceae contamination source of the finished product. These data also highlight Enterobacteriaceae as a good hygiene indicator for the chocolate industry.
•Identification of the Enterobacteriaceae contamination source in chocolate.•Cocoa-based ingredients were not a significant contamination source in chocolate.•Processing environment was the most likely Enterobacteriaceae source in chocolate.
Abstract The non-competitive N-methyl- d -aspartate (NMDA) glutamate receptor antagonist ketamine has been shown to produce cognitive deficits. However, the effects of ketamine on the consolidation ...phase of memory remain poorly characterized. Here we show that systemic administration of ketamine immediately after training dose-dependently impairs long-term retention of memory for a novel object recognition (NOR) task in rats. Control experiments showed that the impairing effects of ketamine could not be attributed to an influence on memory retrieval or sensorimotor effects. In addition, ketamine prevented the increase in hippocampal brain-derived neurotrophic factor (BDNF) levels induced by NOR learning. Our results show for the first time that ketamine disrupts the consolidation phase of long-term recognition memory. In addition, the findings suggest that the amnestic effects of ketamine might be at least partially mediated by an influence on BDNF signaling in the hippocampus.
Histone acetylation is a chromatin modification critically involved in gene regulation during many neural processes. The enzymes that regulate levels of histone acetylation are histone ...acetyltransferases (HATs), which activate gene expression and histone deacetylases (HDACs), that repress gene expression. Acetylation together with other histone and DNA modifications regulate transcription profiles for specific cellular functions. Our previous research has demonstrated a pivotal role for cyclicAMP response element binding protein (CREB)-binding protein (CBP), a histone acetyltransferase, in long-term memory for novel object recognition (NOR). In fact, every genetically modifiedCbp mutant mouse characterized thus far exhibits impaired long-term memory for NOR. These results suggest that long-term memory for NOR is especially sensitive to alterations in CBP activity. Thus, in the current study, we examined the role of HDACs in memory for NOR. We found that inducing a histone hyperacetylated state via HDAC inhibition transforms a learning event that would not normally result in long-term memory into an event that is now remembered long-term. We have also found that HDAC inhibition generates a type of long-term memory that persists beyond a point at which normal memory for NOR fails. This result is particularly interesting because one alluring aspect of examining the role of chromatin modifications in modulating transcription required for long-term memory processes is that these modifications may provide potentially stable epigenetic markers in the service of activating and/or maintaining transcriptional processes.
Double-spin asymmetries in exclusive electroproduction of real photons from a transversely polarized hydrogen target are measured with respect to the product of target polarization with beam helicity ...and beam charge, and with respect to the product of target polarization with beam helicity alone. The asymmetries arise from the deeply virtual Compton scattering process and its interference with the Bethe–Heitler process. They are related to the real part of the same combination of Compton form factors as that determining the previously published transverse target single-spin asymmetries through the imaginary part. The results for the double-spin asymmetries are found to be compatible with zero within the uncertainties of the measurement, and are not incompatible with the predictions of the only available GPD-based calculation.
Evidence for a narrow baryon state is found in quasi-real photoproduction on a deuterium target through the decay channel pK0S→pπ+π−. A peak is observed in the pK0S invariant mass spectrum at ...1528±2.6(stat)±2.1(syst) MeV. Depending on the background model, the naive statistical significance of the peak is 4–6 standard deviations and its width may be somewhat larger than the experimental resolution of σ=4.3–6.2 MeV. This state may be interpreted as the predicted S=+1 exotic Θ+(uudds̄) pentaquark baryon. No signal for an hypothetical Θ++ baryon was observed in the pK+ invariant mass distribution. The absence of such a signal indicates that an isotensor Θ is excluded and an isovector Θ is unlikely.
Bose–Einstein correlations of like-sign charged hadrons produced in deep-inelastic electron and positron scattering are studied in the HERMES experiment using nuclear targets of
1
H,
2
H,
3
He,
4
He, ...N, Ne, Kr, and Xe. A Gaussian approach is used to parametrize a two-particle correlation function determined from events with at least two charged hadrons of the same sign charge. This correlation function is compared to two different empirical distributions that do not include the Bose–Einstein correlations. One distribution is derived from unlike-sign hadron pairs, and the second is derived from mixing like-sign pairs from different events. The extraction procedure used simulations incorporating the experimental setup in order to correct the results for spectrometer acceptance effects, and was tested using the distribution of unlike-sign hadron pairs. Clear signals of Bose–Einstein correlations for all target nuclei without a significant variation with the nuclear target mass are found. Also, no evidence for a dependence on the invariant mass
W
of the photon-nucleon system is found when the results are compared to those of previous experiments.
► We examined the role of mTOR in fear memory. ► Rapamycin in the amygdala or hippocampus around training or retrieval impaired memory. ► mTOR in the amygdala and hippocampus is involved in fear ...memory reconsolidation.
Mammalian target of rapamycin (mTOR), a central regulator of protein synthesis in neurons, has been implicated in synaptic plasticity and memory. Here we show that mTOR inhibition by rapamycin in the basolateral amygdala (BLA) or dorsal hippocampus (DH) impairs both formation and reconsolidation of memory for inhibitory avoidance (IA) in rats. Male Wistar rats received bilateral infusions of vehicle or rapamycin into the BLA or DH before or after IA training or retrieval. Memory retention was tested at different time points after drug infusion. Rapamycin impaired long-term IA retention when given before or immediately after training or retrieval into the BLA. When infused into the DH, rapamycin produced memory impairment when given before training or immediately after retrieval. The impairing effects of post-retrieval rapamycin required memory retrieval and were not reversed by a reminder shock. The results provide the first evidence that mTOR in the BLA and DH might play a role in IA memory reconsolidation.