The vast majority of biologically active compounds, ranging from amino acids to essential nutrients such as glucose, possess intrinsic handedness. This in turn gives rise to chiral optical properties ...that provide a basis for detecting and quantifying enantio-specific concentrations of these molecules. However, traditional chiroptical spectroscopy and imaging techniques require cascading of multiple optical components in sophisticated setups. Here, we present a planar lens with an engineered dispersive response, which simultaneously forms two images with opposite helicity of an object within the same field-of-view. In this way, chiroptical properties can be probed across the visible spectrum using only the lens and a camera without the addition of polarizers or dispersive optical devices. We map the circular dichroism of the exoskeleton of a chiral beetle, Chrysina gloriosa, which is known to exhibit high reflectivity of left-circularly polarized light, with high spatial resolution limited by the numerical aperture of the planar lens. Our results demonstrate the potential of metasurfaces in realizing a compact and multifunctional device with unprecedented imaging capabilities.
In conventional confocal/multiphoton fluorescence microscopy, images are typically acquired under ideal settings and after extensive optimization of parameters for a given structure or feature, often ...resulting in information loss from other image attributes. To overcome the problem of selective data display, we developed a new method that extends the imaging dynamic range in optical microscopy and improves the signal-to-noise ratio. Here we demonstrate how real-time and sequential high dynamic range microscopy facilitates automated three-dimensional neural segmentation. We address reconstruction and segmentation performance on samples with different size, anatomy and complexity. Finally, in vivo real-time high dynamic range imaging is also demonstrated, making the technique particularly relevant for longitudinal imaging in the presence of physiological motion and/or for quantification of in vivo fast tracer kinetics during functional imaging.
The Quality Control (QC) of pre-production strip sensors for the Inner Tracker (ITk) of the ATLAS Inner Detector upgrade has finished, and the collaboration has embarked on the QC test programme for ...production sensors. This programme will last more than 3 years and comprises the evaluation of approximately 22000 sensors. 8 Types of sensors, 2 barrel and 6 endcap, will be measured at many different collaborating institutes. The sustained throughput requirement of the combined QC processes is around 500 sensors per month in total. Measurement protocols have been established and acceptance criteria have been defined in accordance with the terms agreed with the supplier. For effective monitoring of test results, common data file formats have been agreed upon across the collaboration. To enable evaluation of test results produced by many different test setups at the various collaboration institutes, common algorithms have been developed to collate, evaluate, plot and upload measurement data. This allows for objective application of pass/fail criteria and compilation of corresponding yield data. These scripts have been used to process the data of more than 3000 sensors so far, and have been instrumental for identification of faulty sensors and monitoring of QC testing progress.
Glycoprotein Ia (GPIa), also known as integrin alpha 2 (ITGA2), together with GPIIa (ITGB1), form the heterodimer integrin α2β1. This complex is a major collagen receptor on the membrane of ...platelets, which is involved in thrombus formation through platelet adhesion and activation.
Introduction: Main objective of the present study was to investigate the association between the presence of nuchal cord (NC) and the measurement of the ductus venosus pulsatility index for veins ...(ductus venosus (DV) PIV).
Methods: This was a prospective study of 1974 singleton pregnancies that underwent first-trimester screening at 11-13
+6
gestational weeks. Color Doppler was used to demonstrate the presence of a NC in all cases and the DV PIV was calculated routinely, as part of the standard scan. The association between the presence of a NC and the DV PIV was then examined overall and at each gestational week.
Results: A NC was demonstrated in 17.1% of cases. The incidence of nuchal cord was significantly higher at 13-13
+6
weeks (24.7%, n = 119) compared to the one at 12-12
+6
(16.5%, n = 192) and 11-11
+6
weeks (7.9%, n = 26) (p < .001). No significant correlation was found between NC presence and DV PIV (p = .344). The DV PIV was 0.99 (± 0.15) for patients without NC versus 0.99 (± 0.15) for patients with NC (p = .34).
Conclusions: There was no association between the presence of a NC at 11-13
+6
gestational weeks and the DV PIV.
Infertility is a major issue of concern for couples at reproductive age. The underlying causes of infertility remain unknown in 15-30 % of the cases. Plasminogen activator inhibitor type 1 (PAI-1), ...which is a major fibrinolytic factor, has been associated with increased infertility risk. DNA variants at
such as -675 4G/5G promoter polymorphism, have been implicated in infertility-related reproductive disorders, possibly due to a molecular mechanism involving implantation failure. This study aims to investigate the association of
4G/5G polymorphism to otherwise unexplained female infertility in a sample of women of Greek ethnic origins.
We enrolled in this study 222 women from the population of Northern Greece; 115 women with unexplained infertility (group 1) and 107 normal fertile women (group 2). All participants were genotyped for
-675 by real-time polymerase chain reaction.
Our results indicate an association with the
4G allele in our sample of women with unexplained infertility. The dominant genetic model supports the association, in contrast to the recessive genetic model.
Our results indicate that
4G/5G polymorphism is a promising screening factor which could potentially be a target for certain cases of unexplained female infertility. However, they should be interpreted with caution and should be validated in larger studies and diverse populations. In addition, other variants in genes involved in thrombophilia might need to be considered. HIPPOKRATIA 2017, 21(4): 180-185.
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