56 research outputs found

    Compact All-Fiber Quantum-Inspired LiDAR with > 100dB Noise Rejection and Single Photon Sensitivity

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    Entanglement and correlation of quantum light can enhance LiDAR sensitivity in the presence of strong background noise. However, the power of such quantum sources is fundamentally limited to a stream of single photons and cannot compete with the detection range of high-power classical LiDAR transmitters. To circumvent this, we develop and demonstrate a quantum-inspired LiDAR prototype based on coherent measurement of classical time-frequency correlations. This system uses a high-power classical source and maintains the high noise rejection advantage of quantum LiDARs. In particular, we show that it can achieve over 100dB rejection (with 100ms integration time) of indistinguishable(with statistically identical properties in every degrees of freedom) in-band noise while still being sensitive to single photon signals. In addition to the LiDAR demonstration, we also discuss the potential of the proposed LiDAR receiver for quantum information applications. In particular, we propose the chaotic quantum frequency conversion technique for coherent manipulation of high dimensional quantum states of light. It is shown that this technique can provide improved performance in terms of selectivity and efficiency as compared to pulse-based quantum frequency conversion.Comment: 10 pages, 5 figure

    Dietary Calcium but Not Elemental Calcium from Supplements Is Associated with Body Composition and Obesity in Chinese Women

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    We assessed whether dietary calcium intake or calcium supplements associated with body composition and obesity in a Chinese population.A cross-sectional survey was performed in a population of 8940, aged 20 to 74 y. 8127 participants responded (90.9%). Height, weight, fat mass (FM), waist circumference (WC) and hip circumference were measured. Obesity definition: body mass index (BMI) ≥28 kg/m(2) (overall obesity); WC ≥85 cm for men or ≥80 cm for women (abdominal obesity І) and waist hip ratio (WHR) ≥0.90 for men or ≥0.85 for women (abdominal obesity П). The data on dietary calcium and calcium supplements were collected using food-frequency questionnaire and self-report questionnaire. Multivariate linear and multivariable logistic regressions were used to examine the associations between dietary calcium intake or calcium supplements and body composition and obesity.The average dietary calcium intake of all subjects was 430 mg/d. After adjusting for potential confounding factors, among women only, negative associations were observed between habitual dietary calcium intake and four measures of body composition (β, -0.086, P<0.001 for BMI; β, -0.072, P<0.001 for WC; β, -0.044, P<0.05 for WHR; and β, -0.058, P<0.01 for FM, respectively) and both measures of abdominal obesity (Odds Ratio [OR] = 0.86, 95% Confidence Interval [CI], 0.80-0.93; P<0.001, for abdominal obesity I; OR = 0.92, 95% CI, 0.86-0.99; P = 0.026, for abdominal obesity II). These associations were not observed among men (P>0.05). Similarly, among both men and women, we did not observe significant associations between calcium supplements and any measures of body composition or abdominal obesity (P>0.05).Dietary calcium from food rather than elemental calcium from calcium supplements has beneficial effects on the maintenance of body composition and preventing abdominal obesity in Chinese women

    Analysis of hadronic invariant mass spectrum in inclusive charmless semileptonic B decays

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    We make an analysis of the hadronic invariant mass spectrum in inclusive charmless semileptonic B meson decays in a QCD-based approach. The decay width is studied as a function of the invariant mass cut. We examine their sensitivities to the parameters of the theory. The theoretical uncertainties in the determination of ∣Vub∣|V_{ub}| from the hadronic invariant mass spectrum are investigated. A strategy for improving the theoretical accuracy in the value of ∣Vub∣|V_{ub}| is described.Comment: 13 pages, 5 Postscript figure

    Semi-Inclusive B\to K(K^*) X Decays with Initial Bound State Effects

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    The effects of initial bb quark bound state for the semi-inclusive decays B→K(K∗)XB\to K(K^*) X are studied using light cone expansion and heavy quark effective theory methods. We find that the initial bound state effects on the branching ratios and CP asymmetries are small. In the light cone expansion approach, the CP-averaged branching ratios are increased by about 2% with respect to the free bb-quark decay. For Bˉ0→K−(K∗−)X\bar B^0 \to K^- (K^{*-}) X, the CP-averaged branching ratios are sensitive to the phase γ\gamma and the CP asymmetry can be as large as 7% (14%), whereas for B−→Kˉ0(Kˉ∗0)XB^-\to \bar K^0 (\bar K^{*0})X the CP-averaged branching ratios are not sensitive to γ\gamma and the CP asymmetries are small (<1< 1%). The CP-averaged branching ratios are predicted to be in the ranges (0.53∼1.5)×10−4(0.53 \sim 1.5)\times 10^{-4} [(0.25∼2.0)×10−4(0.25 \sim 2.0)\times 10^{-4}] for Bˉ0→K−(K∗−)X\bar B^0 \to K^- (K^{*-})X and (0.77∼0.84)×10−4(0.77 \sim 0.84)\times 10^{-4} [(0.67∼0.74)×10−4(0.67 \sim 0.74)\times 10^{-4}] for B−→Kˉ0(Kˉ∗0)XB^-\to \bar K^0 (\bar K^{*0}) X, depending on the value of the CP violating phase γ\gamma. In the heavy quark effective theory approach, we find that the branching ratios are decreased by about 10% and the CP asymmetries are not affected. These predictions can be tested in the near future.Comment: 29 pages, 12 ps figure

    Benefits and risks of the hormetic effects of dietary isothiocyanates on cancer prevention

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    The isothiocyanate (ITC) sulforaphane (SFN) was shown at low levels (1-5 µM) to promote cell proliferation to 120-143% of the controls in a number of human cell lines, whilst at high levels (10-40 µM) it inhibited such cell proliferation. Similar dose responses were observed for cell migration, i.e. SFN at 2.5 µM increased cell migration in bladder cancer T24 cells to 128% whilst high levels inhibited cell migration. This hormetic action was also found in an angiogenesis assay where SFN at 2.5 µM promoted endothelial tube formation (118% of the control), whereas at 10-20 µM it caused significant inhibition. The precise mechanism by which SFN influences promotion of cell growth and migration is not known, but probably involves activation of autophagy since an autophagy inhibitor, 3-methyladenine, abolished the effect of SFN on cell migration. Moreover, low doses of SFN offered a protective effect against free-radical mediated cell death, an effect that was enhanced by co-treatment with selenium. These results suggest that SFN may either prevent or promote tumour cell growth depending on the dose and the nature of the target cells. In normal cells, the promotion of cell growth may be of benefit, but in transformed or cancer cells it may be an undesirable risk factor. In summary, ITCs have a biphasic effect on cell growth and migration. The benefits and risks of ITCs are not only determined by the doses, but are affected by interactions with Se and the measured endpoint

    Mangiferin Decreases Plasma Free Fatty Acids through Promoting Its Catabolism in Liver by Activation of AMPK

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    Mangiferin has been shown to have the effect of improving dyslipidemia. Plasma free fatty acids (FFA) are closely associated with blood lipid metabolism as well as many diseases including metabolic syndrome. This study is to investigate whether mangiferin has effects on FFA metabolism in hyperlipidemic rats. Wistar rats were fed a high-fat diet and administered mangiferin simultaneously for 6 weeks. Mangiferin (50, 100, 150 mg/kg BW) decreased dose-dependently FFA and triglycerides (TG) levels in plasma, and their accumulations in liver, but increased the β-hydroxybutyrate levels in both plasma and liver of hyperlipidemic rats. HepG2 cells were treated with oleic acid (OA, 0.2 mmol/L) to simulate the condition of high level of plasma FFA in vitro, and were treated with different concentrations of mangiferin simultaneously for 24 h. We found that mangiferin significantly increased FFA uptake, significantly decreased intracellular FFA and TG accumulations in HepG2 cells. Mangiferin significantly increased AMP-activated protein kinase (AMPK) phosphorylation and its downstream proteins involved in fatty acid translocase (CD36) and carnitine palmitoyltransferase 1 (CPT1), but significantly decreased acyl-CoA: diacylgycerol acyltransferase 2 (DGAT2) expression and acetyl-CoA carboxylase (ACC) activity by increasing its phosphorylation level in both in vivo and in vitro studies. Furthermore, these effects were reversed by Compound C, an AMPK inhibitor in HepG2 cells. For upstream of AMPK, mangiferin increased AMP/ATP ratio, but had no effect on LKB1 phosphorylation. In conclusion, mangiferin decreased plasma FFA levels through promoting FFA uptake and oxidation, inhibiting FFA and TG accumulations by regulating the key enzymes expression in liver through AMPK pathway. Therefore, mangiferin is a possible beneficial natural compound for metabolic syndrome by improving FFA metabolism

    Altered urothelial ATP signaling in a major subset of human overactive bladder patients with pyuria

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    Overactive Bladder (OAB) is an idiopathic condition, characterized by urgency, urinary frequency, and urgency incontinence, in the absence of routinely traceable urinary infection. We have described microscopic pyuria (?10 wbc/?l) in patients suffering from the worst symptoms. It is established that inflammation is associated with increased ATP release from epithelial cells, and extracellular ATP originating from the urothelium following increased hydrostatic pressure is a mediator of bladder sensation. Here, using bladder biopsy samples, we have investigated urothelial ATP signaling in OAB patients with microscopic pyuria. Basal, but not stretch-evoked, release of ATP was significantly greater from the urothelium of OAB patients with pyuria than from non-OAB patients or OAB patients without pyuria (<10 wbc/?l). Basal ATP release from the urothelium of OAB patients with pyuria was inhibited by the P2 receptor antagonist suramin and abolished by the hemichannel blocker carbenoxolone, which differed from stretch-activated ATP release. Altered P2 receptor expression was evident in the urothelium from pyuric OAB patients. Furthermore, intracellular bacteria were visualized in shed urothelial cells from ?80% of OAB patients with pyuria. These data suggest that increased ATP release from the urothelium, involving bacterial colonization, may play a role in the heightened symptoms associated with pyuric OAB patients
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