We present the first measurements of the absolute branching fractions of Ξc+ decays into Ξ−π+π+ and pK−π+ final states. Our analysis is based on a data set of (772±11)×106 BB¯ pairs collected at the ...ϒ(4S) resonance with the Belle detector at the KEKB e+e− collider. We measure the absolute branching fraction of B¯0→Λ¯c−Ξc+ with the Ξc+ recoiling against Λ¯c− in B¯0 decays resulting in B(B¯0→Λ¯c−Ξc+)=1.16±0.42(stat.)±0.15(syst.)×10−3. We then measure the product branching fractions B(B¯0→Λ¯c−Ξc+)B(Ξc+→Ξ−π+π+) and B(B¯0→Λ¯c−Ξc+)B(Ξc+→pK−π+). Dividing these product branching fractions by B¯0→Λ¯c−Ξc+ yields B(Ξc+→Ξ−π+π+)=2.86±1.21(stat.)±0.38(syst.)% and B(Ξc+→pK−π+)=0.45±0.21(stat.)±0.07(syst.)%. Our result for B(Ξc+→Ξ−π+π+) can be combined with Ξc+ branching fractions measured relative to Ξc+→Ξ−π+π+ to set the absolute scale for many Ξc+ branching fractions.
We present the analysis of two-particle angular correlations using coordinate
systems defined with the conventional beam axis and the event thrust axis, and
propose the latter to be a useful ...representation for the correlation structure
interpretation in the $e^+ e^-$ collision system. The $e^+ e^-$ collisions to
hadronic final states at center-of-mass energies of $\sqrt{s} = 10.52$ GeV and
$10.58$ GeV are recorded by the Belle detector at KEKB. In this paper, results
on the first dataset are supplementary to the previous Belle publication
arXiv:2201.01694 while the latter one is the first two-particle correlation
measurement at a collision energy on the $\Upsilon(4S)$ resonance and sensitive
to its decay products. Measurements are reported as a function of the
charged-particle multiplicity. Finally, a qualitative understanding of the
correlation structure is discussed using a combination of Monte Carlo
simulations and experimental data.
Toll-like receptor-4 (TLR4) can be activated by nonbacterial agonists, including saturated fatty acids. However, downstream signaling pathways activated by nonbacterial agonists are not known. Thus, ...we determined the downstream signaling pathways derived from saturated fatty acid-induced TLR4 activation. Saturated fatty acid (lauric acid)-induced NFκB activation was inhibited by a dominant-negative mutant of TLR4, MyD88, IRAK-1, TRAF6, or IκBα in macrophages (RAW264.7) and 293T cells transfected with TLR4 and MD2. Lauric acid induced the transient phosphorylation of AKT. LY294002, dominant-negative (DN) phosphatidylinositol 3-kinase (PI3K), or AKT(DN) inhibited NFκB activation, p65 transactivation, and cyclooxygenase-2 (COX-2) expression induced by lauric acid or constitutively active (CA) TLR4. AKT(DN) blocked MyD88-induced NFκB activation, suggesting that AKT is a MyD88-dependent downstream signaling component of TLR4. AKT(CA) was sufficient to induce NFκB activation and COX-2 expression. These results demonstrate that NFκB activation and COX-2 expression induced by lauric acid are at least partly mediated through the TLR4/PI3K/AKT signaling pathway. In contrast, docosahexaenoic acid (DHA) inhibited the phosphorylation of AKT induced by lipopolysaccharide or lauric acid. DHA also suppressed NFκB activation induced by TLR4(CA), but not MyD88(CA) or AKT(CA), suggesting that the molecular targets of DHA are signaling components upstream of MyD88 and AKT. Together, these results suggest that saturated and polyunsaturated fatty acids reciprocally modulate the activation of TLR4 and its downstream signaling pathways involving MyD88/IRAK/TRAF6 and PI3K/AKT and further suggest the possibility that TLR4-mediated target gene expression and cellular responses are also differentially modulated by saturated and unsaturated fatty acids.
Copper is an essential micronutrient for plants. Present at a high concentration in soil, copper is also regarded as a major toxicant to plant cells due to its potential inhibitory effects against ...many physiological and biochemical processes. The interference of germination-related proteins by heavy metals has not been well documented at the proteomic level. In the current study, physiological, biochemical and proteomic changes of germinating rice seeds were investigated under copper stress. Germination rate, shoot elongation, plant biomass, and water content were decreased, whereas accumulation of copper and TBARS content in seeds were increased significantly with increasing copper concentrations from 0.2
mM to 1.5
mM followed by germination. The SDS–PAGE showed the preliminary changes in the polypeptides patterns under copper stress. Protein profiles analyzed by two-dimensional electrophoresis (2-DE) revealed that 25 protein spots were differentially expressed in copper-treated samples. Among them, 18 protein spots were up-regulated and 7 protein spots were down-regulated. These differentially displayed proteins were identified by MALDI-TOF mass spectrometry. The up-regulation of some antioxidant and stress-related proteins such as glyoxalase I, peroxiredoxin, aldose reductase, and some regulatory proteins such as DnaK-type molecular chaperone, UlpI protease, and receptor-like kinase clearly indicated that excess copper generates oxidative stress that might be disruptive to other important metabolic processes. Moreover, down-regulation of key metabolic enzymes like alpha-amylase or enolase revealed that the inhibition of seed germinations after exposure to excess copper not only affects starvation in water uptake by seeds but also results in failure in the reserve mobilization processes. These results indicate a good correlation between the physiological and biochemical changes in germinating rice seeds exposed to excess copper.
Among the direct search experiments for WIMP dark matter, the DAMA experiment observed an annual modulation signal interpreted as WIMP interactions with 9.2\(\sigma\) significance. However, this ...result is contradictory with other direct search experiments reporting null signals in the same parameter space allowed by the DAMA observation, necessitating clarification of the origin of the modulation signal observed using the NaI(Tl) crystals of the DAMA experiment independently. Here, we report the first results of NaI(Tl) crystal measurement at the Yangyang Underground Laboratory to grow ultra-low-background NaI(Tl) crystal detectors.
Choristoma is a benign tumour defined as normal tissue in an ectopic location. Osseous choristoma, one subtype of this entity, occurring within the orbit has rarely been reported in the world ...literature. We report a 6-year-old girl with bilateral ocular osseous choristomas who presented with palpable nodules protruding from both upper lids. The radiological and clinical findings are described and previous reports are reviewed.
Phys. Rev. D 107, 032001 (2023) We present the first search for the weak radiative decays $\Lambda_c^+ \to
\Sigma^+ \gamma$ and $\Xi_c^0 \to \Xi^0 \gamma$ using a data sample of
980~fb$^{-1}$ ...collected by the Belle detector operating at the KEKB
asymmetric-energy $e^+e^-$ collider. There are no evident $\Lambda_c^+ \to
\Sigma^+ \gamma$ or $\Xi_c^0 \to \Xi^0 \gamma$ signals. Taking the decays
$\Lambda_c^+ \to p K^- \pi^+$ and $\Xi_c^0 \to \Xi^- \pi^+$ as normalization
channels, the upper limits at 90\% credibility level on the ratios of branching
fractions ${\cal B}(\Lambda_c^+ \to \Sigma^+ \gamma)/{\cal B}(\Lambda_c^+ \to p
K^{-} \pi^+) < 4.0 \times 10^{-3}$ and ${\cal B}(\Xi_c^0 \to \Xi^0
\gamma)/{\cal B}(\Xi_c^0 \to \Xi^- \pi^+) < 1.2 \times 10^{-2}$ are determined.
We obtain the upper limits at 90\% credibility level on the absolute branching
fractions ${\cal B}(\Lambda_c^+ \to \Sigma^+ \gamma) < 2.6 \times 10^{-4}$ and
${\cal B}(\Xi_c^0 \to \Xi^0 \gamma) < 1.8 \times 10^{-4}$.
The atomic nucleus is made of protons and neutrons (nucleons), which are themselves composed of quarks and gluons. Understanding how the quark-gluon structure of a nucleon bound in an atomic nucleus ...is modified by the surrounding nucleons is an outstanding challenge. Although evidence for such modification-known as the EMC effect-was first observed over 35 years ago, there is still no generally accepted explanation for its cause
. Recent observations suggest that the EMC effect is related to close-proximity short-range correlated (SRC) nucleon pairs in nuclei
. Here we report simultaneous, high-precision measurements of the EMC effect and SRC abundances. We show that EMC data can be explained by a universal modification of the structure of nucleons in neutron-proton SRC pairs and present a data-driven extraction of the corresponding universal modification function. This implies that in heavier nuclei with many more neutrons than protons, each proton is more likely than each neutron to belong to an SRC pair and hence to have distorted quark structure. This universal modification function will be useful for determining the structure of the free neutron and thereby testing quantum chromodynamics symmetry-breaking mechanisms and may help to discriminate between nuclear physics effects and beyond-the-standard-model effects in neutrino experiments.
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