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PURPOSE: Further diagnostic testing may be required after a coronary computed tomography angiography (CTA) showing suspected coronary stenosis. Whether myocardial perfusion imaging (MPI) provides further prognostic information post-CTA remains debated. We evaluated the prognosis for patients completing CTA stratified for post-CTA diagnostic work-up using real-world data.METHODS: We identified all patients in our uptake area with angina symptoms undergoing first-time CTA over a 10-year period. Follow-up time was a median of 3.7 years [1.9-5.8]. The primary endpoint was a composite of myocardial infarction or death. The secondary endpoint was late revascularization.RESULTS: During the study period 53,351 patients underwent CTA. Of these, 24% were referred for further down-stream testing, 3,547 (7%) to MPI and 9,135 (17%) to invasive coronary angiography (ICA). The primary and secondary endpoints occurred in 2,026 (3.8%) and 954 (1.8%) patients. Patient-characteristic-adjusted hazard ratios for the primary and secondary endpoint using patients with a normal CTA as reference were 1.37 (1.21-1.55) and 2.50 (1.93-3.23) for patient treated medically, 1.68 (1.39-2.03) and 6.13 (4.58-8.21) for patients referred to MPI and 1.94 (1.69-2.23) and 9.18 (7.16-11.78) for patients referred for ICA, respectively. Adjusted analysis with stratification for disease severity at CTA showed similar hazard ratios for patients treated medically after CTA and patients referred for MPI and treated medically after the MPI.CONCLUSION: In patients completing coronary CTA, second-line MPI testing seems to identify patients at low risk of future events. MPI seems to have the potential to act as gatekeeper for ICA after coronary CTA.

Aims To investigate the impact of applying coronary computed tomography angiography (CCTA), as the recommended first-line diagnostic test in patients with suspected chronic coronary syndrome (CCS) on the use of invasive coronary angiography (ICA) and revascularization practice. Methods and results We included all patients undergoing a first-time CCTA (n = 53555) and first-time ICA (n = 41451) from 2008 to 2017 due to suspected CCS in Western Denmark (3.3 million inhabitants). The number of CCTA procedures increased from 352 (2008) to 7739 (2017) (2098%), ICA examinations declined from 4538 to 3766 (17%). The average proportion of no- or non-obstructive coronary artery disease by CCTA was 77.5%. Referral to ICA after CCTA occurred in 16.9% of patients in 2008–10 vs. 13.9% in 2014–17 (P 70 years: 9.5% decrease. Conclusion The introduction of CCTA as a first-line diagnostic test in patients with suspected CCS does not associate with increased use of invasive angiography and seems to have facilitated a more appropriate revascularization practice.

The rose flea beetle, RFB (Luperomorpha xanthodera Fairmaire 1888) is a new flower pest in Europe. In 2012, it was brought accidentally to central Poland. To search for this introduced species in the area adjacent to the site of the first finding, 29 plant species belonging to five botanical families (Lamiaceae, Brassicaceae, Asteraceae, Plantaginaceae, Crassulaceae) were monitored over a 3-year-long study (2016−2018). RFB were found on 11 herbaceous/ ornamental plant species (Lamiaceae, Brassicaceae, Asteraceae) along with feeding damage to the flowers. White mustard (Sinapis alba L., Brassicaceae), hyssop (Hyssopus officinalis L.), and Monarda spp. (Lamiaceae) were its most preferred host plants. In each season, RFB females preferred host plants which bloomed abundantly and vividly. However, among the examined plant species there was a large variation in the year-to-year RFB abundance. Over the examined period the RFB extended its abundance exponentially, and its population survived and established itself in the area. The general sex ratio of the beetles was strongly female biased. In the female pool, females with conspicuously swollen abdomens predominated. The results of our study provide more insight into RFB behaviour, its establishment and spreading into new areas. To support the evidence for the RFB risk factor as an agricultural/ horticultural pest, further research should focus on the beetles’ biology, reproductive tactics, larval host plant preference, larva-inflicted damage and harmfulness, the impact of the RFB on the native fauna, as well as its further local and distant migration propensity. Presently our knowledge about these aspects is still fragmentary.

In this paper, we have experimentally investigated polarization properties of the blue phase of a cholesteric liquid crystal in polycrystalline cells with different alignment layers. Experiments were carried out by various temperatures and wavelengths within the spectral range covering Bragg reflection. It was conclusively demonstrated that the change of polarization state of transmitted light through polycrystalline BP-cell is mainly due to Bragg reflection, while optical activity is relatively small. Besides, the linear birefringence was not observed, as expected. It was shown that the ellipticity of the outgoing polarization state can change from almost linear (1.33%) to elliptic (7.33%), depending on sample orientation, with negligible changing of optical rotatory power (for BP I at 470 nm). The results indicate that also polycrystalline BPLC structure, although locally anisotropic, is macroscopically isotropic showing non-negligible optical activity only for resonant wavelengths, although being much lower than that in a typical cholesteric phase. It was also shown that different alignment layers in BP-cell may shift Bragg reflection spectral range, so influencing the outgoing polarization state for particular wavelength.

In this work, optical properties of a cubic blue phase liquid crystal (BPLC) in photonic microstructures were investigated. The experiments were carried out in microcapillaries with different inner diameters and in a photonic crystal fiber (PCF). For the first time, white-light beam propagation through a BPLC (BP II) in a microcapillary with a 60-μm inner diameter at a distance of 26 mm was demonstrated. Furthermore, it was conclusively shown that the cylindrical geometry and the size of its inner diameter influence BP domains orientation, which can lead to a uniform texture of the BPLC with a dominant Bragg wavelength. This study also proves that a BPLC-filled PCF provides very attractive tunable properties. It was presented that by applying an external electric field, a control of the transmitted light intensity for particular wavelengths can be achieved, depending on the input polarization. Moreover, a range of the wavelengths corresponding to low transmission appeared to be tunable, whereas for x- and y-polarized light, respectively, both narrowing (from 16 nm to 9 nm) as well widening (from 13 nm to 22 nm) of the bandgaps were observed. Finally, the obtained experimental results were found qualitatively consistent.

Understanding the dynamics of bodies of water and their impact on the global environment requires sensing information over the full volume of water. In this article, we develop a gradient-based decentralized controller that dynamically adjusts the depth of a network of underwater sensors to optimize sensing for computing maximally detailed volumetric models. We prove that the controller converges to a local minimum and show how the controller can be extended to work with hybrid robot and sensor network systems. We implement the controller on an underwater sensor network with depth adjustment capabilities. Through simulations and in-situ experiments, we verify the functionality and performance of the system and algorithm. Keywords: depth adjustment; adaptive sensing; ocean; sensing; sensor network

New trends are presented in optofluidics based on microstructured photonic crystal fibers filled with liquid crystals. It significantly enhanced optical properties of the fibers and introduced new levels of tunability to photonic crystal fibers. The paper discusses basic research directions in fiber-based optofluidics and, in particular, in polycarbonate-based photonic liquid crystal fibers. Experimental and theoretical results are presented on polymer crystal fibers filled with nematic liquid crystal with two different types of dielectric anisotropies.

Liquid crystals over the last two decades have been successfully used to infiltrate fiber-optic and photonic structures initially including hollow-core fibers and recently micro-structured photonic crystal fibers (PCFs). As a result photonic liquid crystal fibers (PLCFs) have been created as a new type of micro-structured fibers that benefit from a merge of “passive” PCF host structures with “active” LC guest materials and are responsible for diversity of new and uncommon spectral, propagation, and polarization properties. This combination has simultaneously boosted research activities in both fields of Liquid Crystals Photonics and Fiber Optics by demonstrating that optical fibers can be more “special” than previously thought. Simultaneously, photonic liquid crystal fibers create a new class of fiber-optic devices that utilize unique properties of the photonic crystal fibers and tunable properties of LCs. Compared to „classical” photonic crystal fibers, PLCFs can demonstrate greatly improved control over their optical properties. The paper discusses the latest advances in this field comprising PLCFs that are based on nanoparticles-doped LCs. Doping of LCs with nanoparticles has recently become a common method of improving their optical, magnetic, electrical, and physical properties. Such a combination of nanoparticles-based liquid crystals and photonic crystal fibers can be considered as a next milestone in developing a new class of fiber-based optofluidic systems.

In this work we demonstrate the influence of cylindrical shape and alignment layers on light reflection in Blue Phase Liquid Crystals (BPLCs). The process of blue phase (BP) domains growth was observed in a microcapillary for the first time. The cylindrical structure, its diameter and alignment layers influence the orientations of cubic BP domains and affect their growth. A homogeneous BP structure was obtained in a cylindrical tube by changing the temperature and by using external electric field. This study also shows the ability of switching between BP I and chiral phase, in a capillary under the influence of the electric field.

Experimental results of polymer photonic liquid crystal fibers based on commercially available (Kiriama) PMMA and cyclo-olefin polymer (Zeonex 480R) microstructured polymer fibers infiltrated with nematic liquid crystals (2CHBT/8CHBT and PCB) are presented and thermally-tuned photonic band-gap propagation mechanism is observed. These preliminary results suggest, that polymers binding to liquid crystals much easier than silica, can offer new opportunities while using polymer-based photonic crystal fibers.

In this paper propagation effects induced by thermal tuning of photonic band gaps (PBGs) in a polymer photonic crystal fiber (Pol-PCF) infiltrated with a specially designed liquid crystal (LC) are observed. When temperature increases PBGs in the transmission spectrum are narrowing and moving towards shorter wavelengths. However, when the temperature approaches the nematic-isotropic phase transition, PBGs are getting wider and shift back towards longer wavelengths.

We develop a model by choosing the maximum entropy distribution from the set of models satisfying certain smoothness and independence criteria; we show that inference on this model generalizes local kernel estimation to the context of Bayesian inference on stochastic processes. Our model enables Bayesian inference in contexts when standard techniques like Gaussian process inference are too expensive to apply. Exact inference on our model is possible for any likelihood function from the exponential family. Inference is then highly efficient, requiring only O (log N) time and O (N) space at run time. We demonstrate our algorithm on several problems and show quantifiable improvement in both speed and performance relative to models based on the Gaussian process., United States. Office of Naval Research (N00014-09-1-1052), United States. Office of Naval Research (N00014-10-1-0936)