Experimental Observation of Quantum Correlations in Modular Variables

We experimentally detect entanglement in modular position and momentum variables of photon pairs which have passed through $D$-slit apertures. We first employ an entanglement criteria recently proposed in [Phys. Rev. Lett. {\bf 106}, 210501 (2011)], using variances of the modular variables. We then propose an entanglement witness for modular variables based on the Shannon entropy, and test it experimentally. Finally, we derive criteria for Einstein-Podolsky-Rosen-Steering correlations using variances and entropy functions. In both cases, the entropic criteria are more successful at identifying quantum correlations in our data.Comment: 7 pages, 4 figures, comments welcom

Stability of blood gases when refrigerated

Background: Blood gas analysis is a widely used procedure. In clinical practice, the physicians may not always have a blood gas analyzer in their proximity. Not infrequently, blood gas samples are stored in a fridge or on ice and read retrospectively. Continued anaerobic and aerobic metabolism in the blood may alter blood gases in the interval between drawing arterial blood and its analysis, which may cause a fall in the PaO2 and pH and a rise in the PaCO2. Methods: Two sets of arterial blood samples were obtained from hospitalized patients. After the initial analysis, one sample from each patient was put in raw ice within a specimen bag (0 to +1 oC) and the other in the fridge (+4 to +8 oC). These samples were submitted to serial analysis at 30 minutes, 1 hour and 2 hours after the initial analysis. Results: Two hundred arterial blood gas results from 25 patients were analysed. The mean values of PaO2, PaCO2, HCO3-, Na+, K+, Ca2+ and lactate at 0 minutes, 30 minutes, 1 hour and 2 hours were not signifi cantly different between the two alternatives of storage. However, within each group, signifi cant changes were found over time for PaO2, K+, Na+, Ca2+ and lactate. Conclusions: When using plastic syringes, arterial blood gas analysis should be processed shortly after collecting the sample. Despite the fact that low temperatures can slow down the metabolism, neither the ice nor the fridge preserved all the sample parameters

Outage Analysis of Downlink URLLC in Massive MIMO systems with Power Allocation

Massive MIMO is seen as a main enabler for low-latency communications, thanks to its high spatial degrees of freedom. The channel hardening and favorable propagation properties of Massive MIMO are particularly important for multiplexing several URLLC devices. However, the actual utility of channel hardening and spatial multiplexing is dependent critically on the accuracy of channel knowledge. When several low-latency devices are multiplexed, the cost for acquiring accurate knowledge becomes critical, and it is not evident how many devices can be served with a latency-reliability requirement and how many pilot symbols should be allocated. This paper investigates the trade-off between achieving high spectral efficiency and high reliability in the downlink, by employing various power allocation strategies, for maximum ratio and minimum mean square error precoders. The results show that using max-min SINR power allocation achieves the best reliability, at the expense of lower sum spectral efficiency

Gold's hedging and safe haven properties for European stock and bond markets

Most portfolio managers and risk managers strive to pick assets that lead to efficient financial risk mitigation; among them, gold stands out. This paper provides new insights into the role of gold as both a hedge and a safe haven towards European stock and sovereign bond markets. We base the analysis on evidence spanning the Euro's inception to the COVID-19 pandemic spread across Europe. To capture gold's hedge ability, we use the ADCC-GARCH and DCC-GARCH models, while for testing gold's safe haven property we use OLS regressions for different quantiles. Our results show that gold is a hedge for stocks, particularly after the Lehman Brothers collapse. Gold also shows strong safe haven properties for the most extreme negative returns (1% and 2.5% quantiles), and during specific events, such as the Lehman Brothers collapse, the Greek bailout and the Brexit Referendum. Still, for the COVID-19 pandemic outbreak, the results do not confirm this property. Conversely, for bonds, both hedge and safe haven effects are not strongly evident, with gold characterised, at best, as a weak hedge and safe haven. These findings have portfolio allocation implications for investors in European markets, namely fund and risk managers, by pointing out gold hedging and safe haven attributes.info:eu-repo/semantics/publishedVersio

Longevidade de Thielaviopsis paradoxa, agente causal da resinose do coqueiro em Rhynchophorus palmarum.

O objetivo do presente trabalho foi discutir a longevidade do fungo Thielaviopsis paradoxa, agente causal da resinose do estirpe do coqueiro, em seu vetor, o besouro Rhynchophorus palamarum. Foi realizado um estudo microbiológico da superfície e do tubo digestivo dos insetos adultos que foram coletados em duas regiões do Estado de Sergipe: uma com plantações apresentando sintomas da resinose e outra sem focos da doença. Os insetos foram divididos em dois lotes de 40 insetos (20 machos e 20 fêmeas) para cada região. Os besouros foram esfregados um a um em placa de petri contendo meio BDA, um besouro por placa, desinfectados externamente com hipoclorito sódio e o tubo digestivo de cada um dos insetos esfregados foi retirado e dividido em suas três partes principais: estomodeu, mesêntero e proctodeu. Estas partes foram inseridas em meio de cultura BDA e mantidas em BOD a 25 ° C por 5 dias. Foi verificada a patogenicidade dos isolados de T. paradoxa em coqueiros utilizando três métodos de inoculação. Os isolamentos realizados a partir da parte externa e no tubo digestivo dos insetos do município de Neópolis resultaram em 96,3% e 77,5% de crescimento micelial de T. paradoxa respectivamente e foi comprovada a patogenicidade dos isolados em plantas de coqueiro. Ficou comprovado a perda de longevidade do patógeno dentro do vetor após 7 dias, na ausência de nova fonte de infecção

The Exact Critical Bubble Free Energy and the Effectiveness of Effective Potential Approximations

To calculate the temperature at which a first-order cosmological phase transition occurs, one must calculate $F_c(T)$, the free energy of a critical bubble configuration. $F_c(T)$ is often approximated by the classical energy plus an integral over the bubble of the effective potential; one must choose a method for calculating the effective potential when $V''<0$. We test different effective potential approximations at one loop. The agreement is best if one pulls a factor of $\mu^4/T^4$ into the decay rate prefactor [where $\mu^2 = V''(\phi_f)$], and takes the real part of the effective potential in the region $V''<0$. We perform a similar analysis on the 1-dimensional kink.Comment: 11 pages plus 3 figures in jyTeX; CALT-68-188