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The helicity representation of the linear momentum density of a light wave is well understood for monochromatic optical fields in both paraxial and non-paraxial regimes of propagation. In this note we generalize such representation to nonmonochromatic optical fields. We find that, differently from the monochromatic case, the linear momentum density, aka the Poynting vector divided by c 2, does not separate into the sum of right-handed and left-handed terms, even when the so-called electricâ€"magnetic democracy in enforced by averaging the electric and magnetic contributions. However, for quasimonochromatic light, such a separation is approximately restored after time-averaging. This paper is dedicated to Sir Michael Berry on the occasion of his 80th birthday. [ABSTRACT FROM AUTHOR]

In paediatric coeliac disease (CD), symptoms may not be a reliable factor in the diagnosis of coeliac disease as described by Rosen et al,1 and thus, recommendations for reviewing CD screening criteria were suggested.2 Apart from the costs, an important limiting factor in paediatric population mass screening using conventional immunoglobulin (Ig) A tissue transglutaminase (tTGIgA) may be the low compliance of asymptomatic children to be referred for testing. In the first one, a cost of + 20% for POCT was used, while in the second one, to compare POCT screening strategy vs CF, a cost for each FP visit of €15.44 was added to every patient in the CF. For this reason, we suggest that paediatricians utilise POCT in asymptomatic children only and refer children with clinical suspicion of CD for undergoing conventional serology; otherwise, testing for CD might be slowed down by a negative POCT. [Extracted from the article]

Biofiltration systems are a promising retrofit option for site-constrained urban areas due to the vertical arrangement of treatment stages that leads to a relatively compact footprint. Existing knowledge about the influence of their design and configuration on hydrological, stormwater pollutant removal and long-term performance is limited and this has been identified as a barrier to their widespread uptake. Long-term simulations of lined and unlined biofiltration systems in four contrasting UK climatic regimes were used to assess the influence of climate, ponding depth, biofilter to drainage area ratio and infiltration rate on hydrological performance. The results showed that local differences in climate have a significant impact on performance and that infiltration rates as low as 0·36 mm/h are not suitable for locations in the UK with high rainfall unless the biofilter to drainage area ratio is greater than 10%. However, with higher infiltration rates (72 mm/h) a biofilter occupying only 3% of the impermeable catchment area would be capable of infiltrating 97% of annual rainfall in central England. Preliminary results of adsorption and column tests to assess the effectiveness of media amendments, specifically zeolite and granular activated carbon, for dissolved copper and phosphate removal are presented in this paper. [ABSTRACT FROM AUTHOR]

We address the question of whether there exists a hidden relationship between the near-field distribution generated by an oscillating electric dipole and the so-called cross-polarization of a collimated beam of light. We find that the answer is affirmative by showing that the complex field distributions occurring in both cases have a common physical origin: the requirement that the electromagnetic fields must be transverse. [ABSTRACT FROM AUTHOR]

We derive a well-defined renormalized version of mutual information that allows us to estimate the dependence between continuous random variables in the important case when one is deterministically dependent on the other. This is the situation relevant for feature extraction, where the goal is to produce a low-dimensional effective description of a high-dimensional system. Our approach enables the discovery of collective variables in physical systems, thus adding to the toolbox of artificial scientific discovery, while also aiding the analysis of information flow in artificial neural networks. [ABSTRACT FROM AUTHOR]

The Schrödinger equation admits smooth and finite solutions that spontaneously evolve into a singularity, even for a free particle. This blowup is generally ascribed to the intrinsic dispersive character of the associated time evolution. We resort to the notion of quantum Bohmian trajectories to relate this singular behavior to local phase variations, which generate an underlying velocity field responsible for driving the quantum flux toward the singular region. • The dispersive blowup of the Schrödinger equation is investigated. • Local phase variations undergone by the wave function generate an underlying velocity field responsible for driving the quantum flux toward singular regions. • Bohmian trajectories are used to relate the wave function singular behavior to local phase variations. [ABSTRACT FROM AUTHOR]

Quantum approaches relying on entangled photons have been recently proposed to increase the efficiency of optical measurements. We demonstrate here that, surprisingly, the use of classical light with entangled degrees of freedom can also bring outstanding advantages over conventional measurements in polarization metrology. Specifically, we show that radially polarized beams of light allow to perform real-time single-shot Mueller matrix polarimetry. Our results also indicate that quantum optical procedures requiring entanglement without nonlocality can be actually achieved in the classical optics regime. [ABSTRACT FROM AUTHOR]

Due to the increasing mass mortality of Pinna nobilis, mainly caused by the protozoan Haplosporidium pinnae along the Mediterranean Sea, it is necessary to develop rapid and effective methods to detect the pathogen. The present study describes the development and validation of a species-specific assay based on hydrolysis probe chemistry to detect H. pinnae DNA from faeces and pseudofaeces of P. nobilis. During a study campaign in the Gulf of Trieste (Italy) in the spring and summer of 2022, 18 samples (10 faeces and 8 pseudofaeces) were collected. DNA was isolated from all samples and the presence of H. pinnae was tested by amplifying a small portion of 18S rDNA using qPCR. The newly developed assay detected positive H. pinnae in the faeces of the fan mussel in the spring, while no evidence of an outbreak of H. pinnae was found in the summer. In addition, the method proved to be noninvasive and can be used to monitor suspected H. pinnae infections in the early stages when bivalves are still vital. Furthermore, fecal analysis allows the monitoring of P. nobilis without dissecting tissues. The presented assay can also be used to routinely monitor the progress of mass mortalities caused by H. pinnae and to screen for the pathogen in live fan mussels and other environmental matrices, such as water, sediment, and faeces from other species that can host the protozoan. [ABSTRACT FROM AUTHOR]

Complete determination of the polarization state of light requires at least four distinct projective measurements of the associated Stokes vector. Stability of state reconstruction, however, hinges on the condition number k of the corresponding instrument matrix. Optimization of redundant measurement frames with an arbitrary number of analysis states, m, is considered in this Letter in the sense of minimization of k. The minimum achievable k is analytically found and shown to be independent of m, except for m = 5 where this minimum is unachievable. Distribution of the optimal analysis states over the Poincare sphere is found to be described by spherical 2 designs, including the Platonic solids as special cases. Higher order polarization properties also play a key role in nonlinear, stochastic, and quantum processes. Optimal measurement schemes for nonlinear measurands of degree t are hence also considered and found to correspond to spherical 21 designs, thereby constituting a generalization of the concept of mutually unbiased bases. [ABSTRACT FROM AUTHOR]

We generate tightly focused optical vector beams whose electric fields spin around an axis transverse to the beams' propagation direction. We experimentally investigate these fields by exploiting the directional near-field interference of a dipolelike plasmonic field probe placed adjacent to a dielectric interface. This directionality depends on the transverse electric spin density of the excitation field. Near- to far-field conversion mediated by the dielectric interface enables us to detect the directionality of the emitted light in the far field and, therefore, to measure the transverse electric spin density with nanoscopic resolution. Finally, we determine the longitudinal electric component of Belinfante's elusive spin momentum density, a solenoidal field quantity often referred to as "virtual." [ABSTRACT FROM AUTHOR]

Teleportation describes the transmission of information without transport of neither matter nor energy. For many years, however, it has been implicitly assumed that this scheme is of inherently nonlocal nature, and therefore exclusive to quantum systems. Here, we experimentally demonstrate that the concept of teleportation can be readily generalized beyond the quantum realm. We present an optical implementation of the teleportation protocol solely based on classical entanglement between spatial and modal degrees of freedom, entirely independent of nonlocality. Our findings could enable novel methods for distributing information between different transmission channels and may provide the means to leverage the advantages of both quantum and classical systems to create a robust hybrid communication infrastructure. [ABSTRACT FROM AUTHOR]

Biomarkers, especially CRP, have demonstrated their relevance to differentiate viral from bacterial infection, even though a reliable threshold is far to being found. In low- and middle-income countries, affordable and user-friendly rapid diagnostic tests based on biomarkers can be widely adopted to help health workers in the management of non-malarial fever. The primary objective of this study is to assess the best CRP cut-off to distinguish viral from bacterial infections. Other biomarkers were evaluated for the same purpose, alone or in combination with CRP. We retrospectively collected data from two referral hospital departments for infectious and tropical diseases in Italy. Areas under the ROC curve (AUC) were calculated and then compared using the DeLong test. Overall, we included 1193 febrile cases (viral 20.74% vs. bacterial 79.25%). We also collected malaria (n = 202) and intestinal parasite (n = 186) cases to establish their impact on biomarkers. CRP had the best accuracy in differentiating viral from bacterial infections. The best performance of CRP was a cut-off of 11 mg/L. All other biomarkers studied had significantly lower accuracy. Median CRP values were within the normal ranges in parasitic infections, while they were higher in malaria. None of the combinations of CRP with other biomarkers significantly increased the accuracy of CRP alone. [ABSTRACT FROM AUTHOR]