952 research outputs found
Experimental Test of Tracking the King Problem
In quantum theory, the retrodiction problem is not as clear as its classical
counterpart because of the uncertainty principle of quantum mechanics. In
classical physics, the measurement outcomes of the present state can be used
directly for predicting the future events and inferring the past events which
is known as retrodiction. However, as a probabilistic theory,
quantum-mechanical retrodiction is a nontrivial problem that has been
investigated for a long time, of which the Mean King Problem is one of the most
extensively studied issues. Here, we present the first experimental test of a
variant of the Mean King Problem, which has a more stringent regulation and is
termed "Tracking the King". We demonstrate that Alice, by harnessing the shared
entanglement and controlled-not gate, can successfully retrodict the choice of
King's measurement without knowing any measurement outcome. Our results also
provide a counterintuitive quantum communication to deliver information hidden
in the choice of measurement.Comment: 16 pages, 5 figures, 2 table
A new species of Fordiophyton (Sonerileae, Melastomataceae) from Yunnan, China
Fordiophyton jinpingense (Melastomataceae; Sonerileae), a species occurring in south-eastern Yunnan, China, is described as new, based on morphological and molecular data. Phylogenetic analyses, based on nrITS sequence data, showed that, except F. breviscapum, all species sampled in Fordiophyton formed a strongly supported clade in which two geographical lineages were recovered. The generic placement of F. jinpingense is well supported by phylogenetic analyses and a character combination of 4-merous flowers, distinctly dimorphic stamens and the connectives basally not calcarate. Molecular divergence and morphological evidence indicate that F. jinpingense is well separated from other members of the genus, thus justifying its recognition as a distinct species. Fordiophyton jinpingense is phylogenetically closest to F. repens, but differs markedly from the latter in stem morphology (short, obtusely 4-sided vs. long, 4-angular), habit (erect vs. creeping), leaf size (6–16.5 × 4.5–13 cm vs. 4–7.5 × 4–6.5 cm) and flower number per inflorescence (5–13 vs. 3–6)
Protective Role of Hydrogen Sulfide against Noise-Induced Cochlear Damage: A Chronic Intracochlear Infusion Model
Background: A reduction in cochlear blood flow plays an essential role in noise-induced hearing loss (NIHL). The timely regulation of cochlear perfusion determines the progression and prognosis of NIHL. Hydrogen sulfide (H 2S) has attracted increasing interest as a vasodilator in cardiovascular systems. This study identified the role of H2S in cochlear blood flow regulation and noise protection. Methodology/Principal Findings: The gene and protein expression of the H2S synthetase cystathionine-c-lyase (CSE) in the rat cochlea was examined using immunofluorescence and real-time PCR. Cochlear CSE mRNA levels varied according to the duration of noise exposure. A chronic intracochlear infusion model was built and artificial perilymph (AP), NaHS or DLpropargylglycine (PPG) were locally administered. Local sodium hydrosulfide (NaHS) significantly increased cochlear perfusion post-noise exposure. Cochlear morphological damage and hearing loss were alleviated in the NaHS group as measured by conventional auditory brainstem response (ABR), cochlear scanning electron microscope (SEM) and outer hair cell (OHC) count. The highest percentage of OHC loss occurred in the PPG group. Conclusions/Significance: Our results suggest that H2S plays an important role in the regulation of cochlear blood flow and the protection against noise. Further studies may identify a new preventive and therapeutic perspective on NIHL and othe
Prognostic effects of 25-hydroxyvitamin D levels in gastric cancer
<p>Abstract</p> <p>Background</p> <p>Results from large epidemiologic studies on the association between vitamin D and gastric cancer are controversial. Vitamin D significantly promotes apoptosis in the undifferentiated gastric cancer cell, but the prognostic effects of its levels are unknown.</p> <p>Methods</p> <p>197 gastric carcinoma patients who received treatment in the cancer centre of Sun Yat-sen University from January 2002 to January 2006 were involved in the study. The stored blood drawn before any treatment was assayed for 25-hydroxyvitamin D levels. The clinicopathologic data were collected to examine the prognostic effects of vitamin D.</p> <p>Results</p> <p>The mean vitamin D levels of the 197 gastric patients was 49.85 ± 23.68 nmol/L, among whom 114(57.9%) were deficient in Vitamin D(< 50 nmol/L), 67(34%) were insufficient (50-75 nmol/L) and 16(8.1%) were sufficient (> 75 nmol/L). Clinical stage (<it>P </it>= 0.004) and lymph node metastasis classification (<it>P </it>= 0.009) were inversely associated with vitamin D levels. The patients with high vitamin D levels group (≥ 50 nmol/L) had a higher overall survival compared with the low vitamin D levels group (< 50 nmol/L)(<it>P </it>= 0.018). Multivariate analysis indicated that vitamin D levels were an independent prognostic factor of gastric cancer (<it>P </it>= 0.019).</p> <p>Conclusions</p> <p>Vitamin D deficiency may be associated with poor prognosis in gastric cancer.</p
Scaling and memory in the non-poisson process of limit order cancelation
The order submission and cancelation processes are two crucial aspects in the
price formation of stocks traded in order-driven markets. We investigate the
dynamics of order cancelation by studying the statistical properties of
inter-cancelation durations defined as the waiting times between consecutive
order cancelations of 22 liquid stocks traded on the Shenzhen Stock Exchange of
China in year 2003. Three types of cancelations are considered including
cancelation of any limit orders, of buy limit orders and of sell limit orders.
We find that the distributions of the inter-cancelation durations of individual
stocks can be well modeled by Weibulls for each type of cancelation and the
distributions of rescaled durations of each type of cancelations exhibit a
scaling behavior for different stocks. Complex intraday patterns are also
unveiled in the inter-cancelation durations. The detrended fluctuation analysis
(DFA) and the multifractal DFA show that the inter-cancelation durations
possess long-term memory and multifractal nature, which are not influenced by
the intraday patterns. No clear crossover phenomenon is observed in the
detrended fluctuation functions with respect to the time scale. These findings
indicate that the cancelation of limit orders is a non-Poisson process, which
has potential worth in the construction of order-driven market models.Comment: 13 Latex pages, 6 figure
Bardoxolone methyl induces apoptosis and autophagy and inhibits epithelial-to-mesenchymal transition and stemness in esophageal squamous cancer cells
Natural and synthetic triterpenoids have been shown to kill cancer cells via multiple mechanisms. The therapeutic effect and underlying mechanism of the synthetic triterpenoid bardoxolone methyl (C-28 methyl ester of 2-cyano-3,12-dioxoolean-1,9-dien-28-oic acid; CDDO-Me) on esophageal cancer are unclear. Herein, we aimed to investigate the anticancer effects and underlying mechanisms of CDDO-Me in human esophageal squamous cell carcinoma (ESCC) cells. Our study showed that CDDO-Me suppressed the proliferation and arrested cells in G2/M phase, and induced apoptosis in human ESCC Ec109 and KYSE70 cells. The G2/M arrest was accompanied with upregulated p21Waf1/Cip1 and p53 expression. CDDO-Me significantly decreased B-cell lymphoma-extra large (Bcl-xl), B-cell lymphoma 2 (Bcl-2), cleaved caspase-9, and cleaved poly ADP ribose polymerase (PARP) levels but increased the expression level of Bcl-2-associated X (Bax). Furthermore, CDDO-Me induced autophagy in both Ec109 and KYSE70 cells via suppression of the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway. There were interactions between the autophagic and apoptotic pathways in Ec109 and KYSE70 cells subject to CDDO-Me treatment. CDDO-Me also scavenged reactive oxygen species through activation of the nuclear factor (erythroid-derived 2)-related factor 2 (Nrf2) pathway in Ec109 and KYSE70 cells. CDDO-Me inhibited cell invasion, epithelial-mesenchymal transition, and stemness in Ec109 and KYSE70 cells. CDDO-Me significantly downregulated E-cadherin but upregulated Snail, Slug, and zinc finger E-box-binding homeobox 1 (TCF-8/ZEB1) in Ec109 and KYSE70 cells. CDDO-Me significantly decreased the expression of octamer-4, sex determining region Y-box 2 (Sox-2), Nanog, and B lymphoma Mo-MLV insertion region 1 homolog (Bmi-1), all markers of cancer cell stemness, in Ec109 and KYSE70 cells. Taken together, these results indicate that CDDO-Me is a promising anticancer agent against ESCC. Further studies are warranted to explore the molecular targets, efficacy and safety of CDDO-Me in the treatment of ESCC
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