Navigated single-capture 3D and cross-sectional wide-field OCT of the mid and peripheral retina and vitreoretinal interface

Purpose: Assess the mid and peripheral neuroretina and vitreoretinal interface using a novel Navigated Single-Capture 3D and Cross-Sectional Wide-Field Swept-Source Optical Coherence Tomography (WF SS-OCT) technology with correlation to Multi-Wavelength Ultra-Widefield Imaging (MW UWFI) and Histopathology reference. Methods: Retrospective observational study. A total of 74 patients (148 eyes) were imaged using WF SS-OCT and Navigated Single-Capture twelve 23 mm cross-sectional radial scan pattern at 15° intervals. Image diagnosis included: congenital hypertrophy of the retinal pigment epithelium, choroidal nevus, ora serrata pearls, retinal tuft, lattice, snail track, cobblestone degeneration, retinal hole, retinal tear, degenerative retinoschisis, peripheral laser retinopexy, white without pressure, vitreous floaters, subclinical peripheral rhegmatogenous retinal detachment (RD), and tractional RD in proliferative diabetic retinopathy. WF SS-OCT images were correlated with MW UWFI and histopathological references where available. Results: WF SS-OCT successfully imaged structural features in all diagnoses with significant improvement in diagnostic capability and increased the diagnosis of specific features such as vitreoretinal attachment, full thickness hole or tear and subretinal fluid. Histopathological correlation was available for five (5) different peripheral retinal pathologies imaged by both WF SS-OCT and MW UWFI and good anatomical correlation was observed in all diagnosis. Conclusions: Navigated Single-Capture 3D and Cross-Sectional WF SS-OCT provides detailed anatomic information of the mid and peripheral neuroretina and vitreoretinal interface, allowing early recognition of vision-threatening features that may influence clinical management, particularly in an era of telemedicine or when there is limited or no access to Indirect Ophthalmoscopy with 360° Scleral Indentation.

1H NMR based metabolic profiling distinguishes the differential impact of capture techniques on wild bighorn sheep

Environmental metabolomics has the potential to facilitate the establishment of a new suite of tools for assessing the physiological status of important wildlife species. A first step in developing such tools is to evaluate the impacts of various capture techniques on metabolic profiles as capture is necessary to obtain the biological samples required for assays. This study employed 1H nuclear magnetic resonance (NMR)-based metabolite profiling of 562 blood serum samples from wild bighorn sheep to identify characteristic molecular serum makers of three capture techniques (dart, dropnet, and helicopter-based captures) to inform future sampling protocols for metabolomics studies, and to provide insights into the physiological impacts of capture. We found that different capture techniques induce distinct changes in amino acid serum profiles, the urea cycle, and glycolysis, and attribute the differences in metabolic patterns to differences in physical activity and stress caused by the different capture methods. These results suggest that when designing experiments involving the capture of wild animals, it may be prudent to employ a single capture technique to reduce confounding factors. Our results also supports administration of tranquilizers as soon as animals are restrained to mitigate short-term physiological and metabolic responses when using pursuit and physical restraint capture techniques.

1H NMR Based Metabolic Profiling Distinguishes the Differential Impact of Capture Techniques on Wild Bighorn Sheep

Environmental metabolomics has the potential to facilitate the establishment of a new suite of tools for assessing the physiological status of important wildlife species. A first step in developing such tools is to evaluate the impacts of various capture techniques on metabolic profiles as capture is necessary to obtain the biological samples required for assays. This study employed 1H nuclear magnetic resonance (NMR)-based metabolite profiling of 562 blood serum samples from wild bighorn sheep to identify characteristic molecular serum makers of three capture techniques (dart, dropnet, and helicopter-based captures) to inform future sampling protocols for metabolomics studies, and to provide insights into the physiological impacts of capture. We found that different capture techniques induce distinct changes in amino acid serum profiles, the urea cycle, and glycolysis, and attribute the differences in metabolic patterns to differences in physical activity and stress caused by the different capture methods. These results suggest that when designing experiments involving the capture of wild animals, it may be prudent to employ a single capture technique to reduce confounding factors. It also supports administration of tranquilizers as soon as animals are restrained to mitigate stress and other physiological and metabolic responses.

Carbon Capture From Flue Gas and the Atmosphere: A Perspective

Climate change has become a worldwide concern with the rapid rise of the atmospheric Co2 concentration. To mitigate Co2 emissions, the research and development efforts in Co2 capture and separation both from the stationary sources with high Co2 concentrations (e.g., coal-fired power plant flue gas) and directly from the atmosphere have grown significantly. Much progress has been achieved, especially within the last twenty years. In this perspective, we first briefly review the current status of carbon capture technologies including absorption, adsorption, membrane, biological capture, and cryogenic separation, and compare their advantages and disadvantages. Then, we focus mainly on the recent advances in the absorption, adsorption, and membrane technologies. Even though numerous optimizations in materials and processes have been pursued, implementing a single separation process is still quite energy-intensive or costly. To address the challenges, we provide our perspectives on future directions of Co2 capture research and development, that is, the combination of flue gas recycling and hybrid capture system, and one-step integrated Co2 capture and conversion system, as they have the potential to overcome the technical bottlenecks of single capture technologies, offering significant improvement in energy efficiency and cost-effectiveness.

SEAMLESS CO-REGISTRATION OF IMAGES FROM MULTI-SENSOR MULTISPECTRAL CAMERAS

Small-format, consumer-grade multi-camera multispectral systems have gained popularity in recent years. This is specifically due to the simplicity of their integration onboard platforms with limited payload capacity, such as Unmanned Aerial Vehicles (UAVs). Commercially available photogrammetric software can process the image data collected by these cameras to create multispectral ortho-rectified mosaics. However, misalignments of several pixels between spectral bands have been observed to be a common issue when employing these solutions, which can undermine the spectral and geometric integrity of the data. Besides, in advanced processing workflows such as object detection and classification with deep learning algorithms, band-to-band co-registered images are needed rather than one mosaic. We propose a two-fold solution for seamless band-to-band registration of images captured by five cameras integrated into a miniature multispectral camera system. This approach consists of 1) a robust self-calibration of the multispectral camera system to accurately estimate the intrinsic calibration parameters and relative orientation parameters of all cameras; 2) a single capture, band-to-band co-registration method based on trifocal constraints. This approach differs from existing literature since it is fully automatic, does not make any assumptions about the scene, does not use any best-fit projective or similarity transformations, and does not attempt cross-spectral feature-point matching. Our experiments confirm that the proposed co-registration method can accurately fuse multispectral images from a miniature multi-camera system and is invariant to large depth-variations in the captured scene.

An Algorithm for the Removal of Cosmic Ray Artifacts in Spectral Data Sets

Cosmic ray artifacts may be present in all photo-electric readout systems. In spectroscopy, they present as random unidirectional sharp spikes that distort spectra and may have an affect on post-processing, possibly affecting the results of multivariate statistical classification. A number of methods have previously been proposed to remove cosmic ray artifacts from spectra but the goal of removing the artifacts while making no other change to the underlying spectrum is challenging. One of the most successful and commonly applied methods for the removal of comic ray artifacts involves the capture of two sequential spectra that are compared in order to identify spikes. The disadvantage of this approach is that at least two recordings are necessary, which may be problematic for dynamically changing spectra, and which can reduce the signal-to-noise (S/N) ratio when compared with a single recording of equivalent duration due to the inclusion of two instances of read noise. In this paper, a cosmic ray artefact removal algorithm is proposed that works in a similar way to the double acquisition method but requires only a single capture, so long as a data set of similar spectra is available. The method employs normalized covariance in order to identify a similar spectrum in the data set, from which a direct comparison reveals the presence of cosmic ray artifacts, which are then replaced with the corresponding values from the matching spectrum. The advantage of the proposed method over the double acquisition method is investigated in the context of the S/N ratio and is applied to various data sets of Raman spectra recorded from biological cells.

A modified sequence capture approach allowing standard and methylation analyses of the same enriched genomic DNA sample

BackgroundBread wheat has a large complex genome that makes whole genome resequencing costly. Therefore, genome complexity reduction techniques such as sequence capture make re-sequencing cost effective. With a high-quality draft wheat genome now available it is possible to design capture probe sets and to use them to accurately genotype and anchor SNPs to the genome. Furthermore, in addition to genetic variation, epigenetic variation provides a source of natural variation contributing to changes in gene expression and phenotype that can be profiled at the base pair level using sequence capture coupled with bisulphite treatment. Here, we present a new 12 Mbp wheat capture probe set, that allows both the profiling of genotype and methylation from the same DNA sample. Furthermore, we present a method, based on Agilent SureSelect Methyl-Seq, that will use a single capture assay as a starting point to allow both DNA sequencing and methyl-seq.ResultsOur method uses a single capture assay that is sequentially split and used for both DNA sequencing and methyl-seq. The resultant genotype and epi-type data is highly comparable in terms of coverage and SNP/methylation site identification to that generated from separate captures for DNA sequencing and methyl-seq. Furthermore, by defining SNP frequencies in a diverse landrace from the Watkins collection we highlight the importance of having genotype data to prevent false positive methylation calls. Finally, we present the design of a new 12 Mbp wheat capture and demonstrate its successful application to re-sequence wheat.ConclusionWe present a cost-effective method for performing both DNA sequencing and methyl-seq from a single capture reaction thus reducing reagent costs, sample preparation time and DNA requirements for these complementary analyses.