Line Mapping Research Articles

Pan-cancer proteomic map of 949 human cell lines.

SummaryThe proteome provides unique insights into disease biology beyond the genome and transcriptome. A lack of large proteomic datasets has restricted the identification of new cancer biomarkers. Here, proteomes of 949 cancer cell lines across 28 tissue types are analyzed by mass spectrometry. Deploying a workflow to quantify 8,498 proteins, these data capture evidence of cell-type and post-transcriptional modifications. Integrating multi-omics, drug response, and CRISPR-Cas9 gene essentiality screens with a deep learning-based pipeline reveals thousands of protein biomarkers of cancer vulnerabilities that are not significant at the transcript level. The power of the proteome to predict drug response is very similar to that of the transcriptome. Further, random downsampling to only 1,500 proteins has limited impact on predictive power, consistent with protein networks being highly connected and co-regulated. This pan-cancer proteomic map (ProCan-DepMapSanger) is a comprehensive resource available at https://cellmodelpassports.sanger.ac.uk.

Effect of electrophysiological mapping on non-transmural annulus ablation and atrial fibrillation recurrence prediction after 6 months of Cox-Maze IV procedure.

ObjectiveThe objective of this study was to observe the safety and efficacy of electrophysiological mapping following the Cox-Maze IV procedure and to investigate whether a correlation exists between recurrence of atrial fibrillation (AF) with the completeness of bidirectional electrical isolation and the inducibility of AF immediately after the Cox-Maze IV procedure.MethodsTotally, 80 consecutive patients who suffered from aortic valve or mitral valve disease and persistent AF were randomly enrolled into the control group and electrophysiological mapping following the Cox-Maze IV group (Electrophysio-Maze group). In the Electrophysio-Maze group, patients underwent concomitant Cox-Maze procedure and following electrophysiological mapping of ablation lines in mitral isthmus, left atrial “box,” and tricuspid annulus. If the bidirectional electrical isolation of tricuspid annulus ablation line is incomplete, whether to implement supplementary ablation will be independently decided by the operator. Before and after the Cox-Maze IV procedure, AF induction was performed. All patients in both groups were continuously followed-up and underwent electrocardiogram Holter monitoring after 6 months.ResultsIn total, 42 Electrophysio-Maze patients and 38 controls were enrolled. Compared with patients in the control group, there were shorter hospital stay, better cardiac remodeling changes, and higher relief from AF during the follow-up period of 6 months in the Electrophysio-Maze group. Within the Electrophysio-Maze group, the rate of incomplete the bidirectional electrical isolation of “box” ablation lines was zero, and the rate of incomplete bidirectional electrical isolation of mitral isthmus ablation line or tricuspid annulus ablation line was 23.8%. After two cases of successful complementary ablation on the tricuspid annulus ablation line, the final incomplete bidirectional electrical isolation of annulus ablation lines was 19.0%. There were correlations between late AF recurrence after 6 months with incomplete bidirectional electrical isolation of annulus ablation lines and AF induction immediately after the Cox-Maze IV procedure.ConclusionElectrophysiological mapping following the Cox-Maze procedure is safe and effective. Electrophysiological mapping in the Cox-Maze procedure can find out the non-transmural annulus ablation lines by assessing the completeness of bidirectional electrical isolation of ablation lines, guide supplementary ablation, and predict AF recurrence after 6 months.

Genetic mapping of QTL for three root-related traits in wheat (Triticum aestivum)

A well-developed root system plays a positive role in wheat yield. Here, we identified quantitative trait loci (QTL) for total root length (TRL), root average diameter (RD) and number of root tips (RTN) based on the previously developed genetic map of a recombinant inbred line (RIL) population in bread wheat and phenotype data from two individual trials. A stable and major QTL, Qtrl-AS-5A for TRL was detected explaining 17.19 to 17.78% of the phenotypic variation. It was physically located at 680.66-683.25 Mb (∼2.59 Mb interval) on chromosome arm 5AL. Two stably expressed QTLs for RD, Qrd-AS-4A and Qrd-AS-6B, were identified. The phenotype variances explained for them were between 5.11 to 5.43% and 17.42 to 22.40%, respectively. They were physically located at 621.74 Mb-621.93 Mb (∼0.19 Mb) on 4AL and 624.01 − 624.78 Mb (∼0.77 Mb) on 6BL, respectively. One unstably expressed QTL for RN was identified only. Genetic analysis suggested that the two major and stably expressed QTLs, Qtrl-AS-5A and Qrd-AS-6B, were not likely associated with plant height and anthesis date. Comparison analysis indicated that they may be novel loci. Several candidate genes which were mainly expressed in roots were also obtained. Collectively, these results provided several major and stably expressed QTLs for root traits and they should have breeding potential.

Hot corrosion and air oxidation behavior of pulsed current gas tungsten arc welded and CO2 laser beam welded SMO 254 at 800 °C

This research aims to investigate the hot corrosion behaviour of SMO 254 steel samples after PCGTA and CO2 laser beam welding, as well as air oxidation. A salt mixture simulated the waste incinerator environment involving 40 wt. % Na2SO4 + 40 wt. % K2SO4 + 10 wt. % NaCl + 10 wt. % KCl are employed. The hot corrosion tests were carried out for 103.33 h at 800 °C, with a thermogravimetric investigation availed to calculate the impact of corrosion. The weight gain rate for PCGTAW molten salt corroded specimens is greater (33.45 mg/cm2) than the weight gain rate for CO2 Laser molten salt corroded specimens, which is 67.55% higher. The weight of the hot corroded sample rises in the molten salt surroundings due to the creation of compounds including CrS, FeMo2S4, Na2S, Fe2O3, K2S3, Cl4CrNa2. CO2 LBW air oxidation has the lowest rate of corrosion due to the synthesis of beneficial oxides, such as NiCr2O4, NiO, and Cr2O3. Optical microscopy and SEM/EDS were employed on both surface and cross-sectional surfaces to get microstructure at the interface of the fusion region, parent metal, and fusion region using point mapping, line mapping, and X-ray mapping techniques. The corrosion products produced during corrosion were studied using XRD.

Object ground lines regression and mapping from fisheye images to around view image for the AVP

The automated valet parking (AVP) based on the around view monitor (AVM) has attracted increasing attention from the research community due to its high practicality and low cost. However, the distortion correction and inverse perspective transformation of the around view images result in the truncated and deformed objects, which leads to poor detection performance. To address this problem, we propose a method of object ground lines regression and mapping from fisheye images to around view images. There are two key steps for the proposed method, regressing ground lines in the fisheye images and mapping ground lines to the around view image. To detect the objects and regress ground lines at the same time, we explored three new detectors based on YOLOv5 (i.e. YOLOv5-VGG, YOLOv5-Point, and YOLOv5-Ratio). Among them, YOLOv5-VGG adds a VGG-based regression network behind YOLOv5, YOLOv5-Point directly adds a regression head to share the convolutional features, and YOLOv5-Ratio combines the 2D box and ground line to predict its ratios. After that, the ground lines from four different views are mapped and fused to the around view image. Additionally, to facilitate the study of the object detection in the around view image, a large-scale labeled dataset is established, which comprises 9828 fisheye images collected from typical indoor and outdoor parking lots. For each image, the 2D bounding boxes and ground lines of objects are carefully labeled. Experiments show that the YOLOv5-Ratio obtains the best performance and can effectively detect the truncated and deformed object in the around view image with the precision rate of 92.28% and recall rate of 85.09% on our collected dataset.

Effect of microwave sintering on the microstructure and tribological behavior of Ti-3Al-2.5 V-xWC composite

Ti-3Al-2.5 V-xWC composite was fabricated through Microwave Sintering (MS) technique. Tungsten Carbide (WC) with 0.5, 1.0, 1.5, 2.0 and 2.5 (by weight %) were dispersed in matrix. Specimens were densified using microwave sintering technique at 1200 °C. The fabricated composites were characterized using Field Emission Scanning Electron Microscope (FE-SEM) with Energy Dispersive Analysis (EDS) line mapping. Densification, Microstructure, mechanical properties and dry sliding wear behavior were examined. The results revealed that higher density after sintering, improved the mechanical and wear behavior. It reached maximum hardness of 298VHN, Wear rate of 0.33 × 10−4 mm3/m and Coefficient of Friction of 0.45 for Ti-3Al-2.5 V-2WC composite. It was also established that microwave sintering with less sintering time helps to reduce the defect during sintering.

A Fusion Map Matching Method for Low-Cost Ground Autonomic Positioning System

Map matching technology is an effective way to improve the accuracy of ground inertial positioning systems by similarity comparison of vehicle trajectory and road shape characteristics. Traditional point matching algorithm can correct the inertial positioning errors in time through continuous projection operation, but it is prone to mismatch in urban complex road networks with similar shape features. Line matching algorithm can reduce the probability of false matching, but it demands to waiting obvious road bending characteristics, leading to the problem of untimely error correction. Therefore, an innovative fusion map matching method is proposed in this paper, aiming to make an organic combination of the advantages of point and line map matching algorithms, especially for accuracy improvement of low-cost ground autonomic positioning systems. Moreover, the paper discusses the influence of inertial positioning error characteristics on map matching accuracy, pointing out the original positioning errors with gentle fluctuation is more conducive to further improve map matching performance. The correctness and feasibility of proposed fusion matching method are demonstrated by a vehicle experiment, proving that positioning accuracy could be improved by 22.5% compared with traditional line map matching method.

The thesan project: predictions for multitracer line intensity mapping in the epoch of reionization

ABSTRACT Line intensity mapping (LIM) is rapidly emerging as a powerful technique to study galaxy formation and cosmology in the high-redshift Universe. We present LIM estimates of select spectral lines originating from the interstellar medium (ISM) of galaxies and 21 cm emission from neutral hydrogen gas in the Universe using the large volume, high resolution thesan reionization simulations. A combination of subresolution photoionization modelling for H ii regions and Monte Carlo radiative transfer calculations is employed to estimate the dust-attenuated spectral energy distributions (SEDs) of high-redshift galaxies (z ≳ 5.5). We show that the derived photometric properties such as the ultraviolet (UV) luminosity function and the UV continuum slopes match observationally inferred values, demonstrating the accuracy of the SED modelling. We provide fits to the luminosity–star formation rate relation (L–SFR) for the brightest emission lines and find that important differences exist between the derived scaling relations and the widely used low-z ones because the ISM of reionization era galaxies is generally less metal enriched than in their low-redshift counterparts. We use these relations to construct line intensity maps of nebular emission lines and cross-correlate with the 21 cm emission. Interestingly, the wavenumber at which the correlation switches sign (ktransition) depends heavily on the reionization model and to a lesser extent on the targeted emission line, which is consistent with the picture that ktransition probes the typical sizes of ionized regions. The derived scaling relations and intensity maps represent a timely state-of-the-art framework for forecasting and interpreting results from current and upcoming LIM experiments.

Identification of QTLs for zinc deficiency tolerance in a recombinant inbred population of rice (Oryza sativa L.).

Deficiency of Zn is a major soil constraint in rice plant growth and yield. Edaphic factors such as Zn deficiency in soil in relation to plant performance are still poorly understood. Here, we report promising quantitative trait loci (QTL) conferring tolerance to Zn deficiency, which were identified through biparental mapping. The experiment was conducted using the 236 F7 recombinant inbred line mapping population derived from the cross of Kinandang Patong (Zn deficiency sensitive) and A69-1 (Zn deficiency tolerant). A total of six QTLs (qLB-2B, qLB-4B, qPM-4B, qPM-6B, qRZC-4B, qSZC-4B) on chromosomes 2, 4 and 6 were identified for environment 1, whereas five QTLs (qLB-2 N, qLB-4N, qPM-4N, qRZC-4N, qSZC-4 N) on chromosomes 2 and 4 were detected for environment 2. Among these, five major (51.30, 48.70, 28.60, 56.00, 52.00 > 10 R2 ) and one minor (5.40 < 10 R2 ) QTLs for environment 1 and four major (51.48, 50.20, 53.00, 48.00 > 10 R2 ) and one minor (4.44 < 10) QTLs for environment 2 for Zn deficiency tolerance with a logarithm of odd threshold value higher than 3 were identified. The QTLs (qLB-4B, qPM-4B, qRZC-4B, qSZC-4B, qLB-4N, qPM-4N, qRZC-4N, qSZC-4N) for leaf bronzing, plant mortality root zinc concentration and shoot zinc concentration identified on chromosome 4 were found to be the most promising and highly reproducible across the locations that explained phenotypic variation from 48.00% to 56.00% with the same marker interval RM6748-RM303. The new QTLs and its linked markers identified in the present study can be utilized for Zn deficiency tolerance in elite cultivars using marker-assisted backcrossing. © 2022 Society of Chemical Industry.

HGG-02. Epigenetic transcription regulation and 3D genome structure in pediatric high-grade glioma

INTRODUCTION: Pediatric high-grade gliomas (pHGGs), including glioblastoma multiforme (GBM) and diffuse intrinsic pontine glioma (DIPG), are highly morbid brain tumors. Up to 80% of DIPGs harbor a somatic missense mutation in genes encoding Histone H3. To investigate whether the H3K27M mutant protein is associated with distinct chromatin structure affecting transcription regulation, we generated the first high-resolution Hi-C and ATAC-Seq maps of pHGG cell lines, and integrated these with tissue and cell genomic data. METHODS: We generated sequencing data from patient-derived cell lines (DIPG n=6, GBM n=3, normal n=2) and frozen tissue specimens (DIPG n=1, normal brainstem n=1). Analyses included cell line RNA-Seq, ChIP-Seq (H3K27ac, H3K27me3, H3K27M) and genome-wide chromatin conformation capture (Hi-C), as well as tissue ATAC-Seq. Publicly available pediatric glioma tissue ChIP-Seq data was integrated with cell data. CRISPR knock-down of target enhancer regions was performed. RESULTS: We identified tumor-specific enhancers and regulatory networks for known oncogenes in DIPG and GBM. In DIPG, FOX, SOX, STAT and SMAD families were among top H3K27Ac enriched motifs. Significant differences in Topologically Associating Domains (TADs) and DNA looping were observed at OLIG2 and MYCN in H3K27M mutant DIPG, relative to wild-type GBM and normal cells. Pharmacologic treatment targeting H3K27Ac (BET and Bromodomain inhibition) altered these 3D structures. Functional analysis of differentially enriched enhancers in DIPG implicated SOX2, SUZ12, and TRIM24 as top activated upstream regulators. Distinct genomic structural variations leading to enhancer hijacking and gene co-amplification were identified at A2M, JAG2, and FLRT1. CONCLUSION: We show genome structural variations enhancer-promoter interactions that impact gene expression in pHGG in the presence and absence of the H3K27M mutation. Our results imply that tridimensional genome alterations may play a critical role in the pHGG epigenetic landscape and thereby contribute to pediatric gliomagenesis. Further studies examining the impact of the alterations are therefore underway.

Influences of Ag+LiAlO2 on mechanical and high temperature wear behavior of magnesium hybrid composites

The objective of this research is to analyze the mechanical such as porosity; hardness and high temperature wear behavior of Magnesium (MgZE41A) hybrid composites reinforced with Silver (Ag) and Lithium Aluminate (LiAlO2). The various wt. % such as Ag (1.0 &amp; 1.5) and LiAlO2 (1.0 &amp; 1.5) was reinforced in MgZE41A using Powder Metallurgy (P/M) technique. The sintered composites were characterized using Scanning Electron Microscope (SEM) coupled with Energy Dispersive Spectroscopy (EDS) line mapping Technique. The porosity and Vicker’s hardness of the samples were assessed. Further, the high temperature wear behavior of the composites was evaluated using tribometer with heater setup by varying the heat inputs such as 30°C, 50°C, 100°C, 150°C and 200°C. The results revealed that increasing the wt. % of Ag and LiAlO2 led to decrease the porosity from 0.11 % to 0.09 % due to high compacting pressure and sintering temperature. High temperature Wear rate of the composites was reduced from 2.15 * 10-4 to 0.83 * 10-4 because of wt. % of reinforcement, high compacting pressure and better sintering temperature.

Glacier Mass Balance Based on Two Digital Elevation Models and Ground Observation Records for the Baishui River Glacier No. 1 in Yulong Snow Mountain, Southeastern Qinghai–Tibet Plateau

Glacier mass balance is a key idea in understanding the relationship between glaciers and climate. In this study, Landsat images, Shuttle Radar Topography Mission, and Advance Land Operation Satellite digital elevation models, and ground observation records for 2000–2010 and 2019–2020 were used to analyze a mass balance of the Baishui River Glacier No. 1 (BRG1) in Yulong Snow Mountain, southeastern Qinghai–Tibet Plateau. Both glaciological and geodetic methods were used to understand the spatial pattern of the mass balance. A mass balance contour line map of the glacier was created for the first time. From 2000 to 2010, the mean annual mass balance of the BRG1 was calculated to be -0.99 m w.e., -1.01 m w.e., and −1.18 m w.e. using the contour line, profile curve, and geodetic methods, respectively. In addition, the analysis revealed that strong melting of the glacier occurred from July 27 to 15 September 2019, with an averaged glacier mass balance of -1.75 m w.e. and a mean daily melting rate of 35 mm w.e. The annual mass balance was assessed to be −1.31 m w.e. during 2019/20 using the contour line method. In addition, the spatial patterns on the mass balance contour maps for 2000–2010 and the summer of 2019, and the climate change in this region were analyzed. The results indicate that the increased air temperature was the main cause of the accelerated glacial melting.

Accurate Ranging Based on Transmission Line Channel Monitoring Image and Point Cloud Data Mapping

Three-dimensional (3D) mapping of power lines is essential for power line inspection. Many remotely sensed data products like light detection and ranging (LiDAR) have been examined for power line surveys. More and more data are being obtained via photogrammetric measurements. This increases the need for the implementation of advanced processing techniques. In recent years, there has been a significant advancement in visualization techniques for power lines using unmanned aerial vehicle (UAV) platform photography. The most advanced of such imaging systems can create dense point clouds. However, the accuracy is very often unstable and dependent on the radiometric quality of images and the efficiency of the image processing technique. In this study, the two-dimensional information is obtained by photographing the real-time panorama of the transmission line channel using a 3D camera, and the three-dimensional information is acquired using laser radar technology. The three-dimensional point orientation of the target object and the transmission line is determined using the mapping relationship between two and three dimensions, the obtained data are calculated, and the calculation results are produced. The proposed method can solve the problem of the image sensor being unable to map spatial distance and can provide broad coverage of the transmission line channel and 24-hours accurate real-time remote monitoring.

A multiview-based automatic method for 3D fracture line extraction

The 3D fracture line is the centerline of the crack region on the surface of the bone that can effectively help orthopedists understand fracture distribution and aid in fracture treatment. However, no effective automatic extraction method exists, and fracture lines still require manual work. This paper develops an efficient automatic method for fracture line extraction from multiple reassembled fragments. In the initial step, we propose a multiview sampling strategy based on spherical uniform viewpoints, which uses off-screen rendering to sample fragments from multiple viewpoints. Markers are generated from the samples and integrated from all viewpoints. Then, we use a new point-based centerline extraction algorithm to merge markers and extract the fracture lines. Finally, we propose a normal-based fracture line mapping method to quickly and reliably map fracture lines to the surface of a standard bone template. Experiments indicate that our method can extract fracture lines from six common complex fragments within 3 s. Through multiview experiments, we select 30 viewpoints so that most template mesh triangles corresponding to the six fragments can be simultaneously observed from at least 2 viewpoints. Additionally, anti-noise experiments show that the proposed method can handle high-noise and cancellous fragments reliably. For complex fragments, our method is still applicable, has strong practicality, and can effectively help doctors save time.

A Study of Photoionized Gas in Two H ii Regions of the N44 Complex in the LMC Using MUSE Observations

We use the optical integral field observations with Multi-Unit Spectroscopic Explorer (MUSE) on the Very Large Telescope, together with CLOUDY photoionization models, to study ionization structure and physical conditions of two luminous H ii regions in the N44 star-forming complex of the Large Magellanic Cloud. The spectral maps of various emission lines reveal a stratified ionization geometry in N44 D1. The spatial distribution of [O i] λ6300 emission in N44 D1 indicates a partially covered ionization front at the outer boundary of the H ii region. These observations reveal that N44 D1 is a blister H ii region. The [O i] λ6300 emission in N44 C does not provide a well-defined ionization front at the boundary, while patches of [S ii] λ6717 and [O i] λ6300 emission bars are found in the interior. The results of spatially resolved MUSE spectra are tested with the photoionization models for the first time in these H ii regions. A spherically symmetric ionization-bounded model with a partial covering factor, which is appropriate for a blister H ii region, can well reproduce the observed geometry and most of the diagnostic line ratios in N44 D1. Similarly, in N44 C we apply a low-density and optically thin model based on the observational signatures. Our modeling results show that the ionization structure and physical conditions of N44 D1 are mainly determined by the radiation from an O5 V star. However, local X-rays, possibly from supernovae or stellar wind, play a key role. In N44 C, the main contribution is from three ionizing stars.

CRISPR/Cas9-Mediated Disruption of Xylanase inhibitor protein (XIP) Gene Improved the Dough Quality of Common Wheat.

The wheat dough quality is of great significance for the end-use of flour. Some genes have been cloned for controlling the protein fractions, grain protein content, starch synthase, grain hardness, etc. Using a unigene map of the recombinant inbred lines (RILs) for “TN 18 × LM 6,” we mapped a quantitative trait locus (QTL) for dough stability time (ST) and SDS-sedimentation values (SV) on chromosome 6A (QSt/Sv-6A-2851). The peak position of the QTL covered two candidate unigenes, and we speculated that TraesCS6A02G077000 (a xylanase inhibitor protein) was the primary candidate gene (named the TaXip gene). The target loci containing the three homologous genes TaXip-6A, TaXip-6B, and TaXip-6D were edited in the variety “Fielder” by clustered regularly interspaced short palindromic repeats–associated protein 9 (CRISPR/Cas9). Two mutant types in the T2:3 generation were obtained (aaBBDD and AAbbdd) with about 120 plants per type. The SVs of aaBBDD, AAbbdd, and WT were 31.77, 27.30, and 20.08 ml, respectively. The SVs of the aaBBDD and AAbbdd were all significantly higher than those of the wild type (WT), and the aaBBDD was significantly higher than the AAbbdd. The STs of aaBBDD, AAbbdd, and WT were 2.60, 2.24, and 2.25 min, respectively. The ST for the aaBBDD was significantly higher than that for WT and was not significantly different between WT and AAbbdd. The above results indicated that XIP in vivo can significantly affect wheat dough quality. The selection of TaXip gene should be a new strategy for developing high-quality varieties in wheat breeding programs.

The Fornax3D project: The environmental impact on gas metallicity gradients in Fornax cluster galaxies

The role played by environment in galaxy evolution is a topic of ongoing debate among astronomers. There has been little success in elucidating the degree to which environment can alter, re-shape, or drive galaxy evolution, that is, using either observations or simulations. However, our knowledge of the effect of environment on gas metallicity gradients remains limited. Here we present our analysis of the gas metallicity gradients for a sample of ten Fornax cluster galaxies observed with MUSE as part of the Fornax3D project. We used detailed maps of emission lines to determine precise values of gas metallicity and metallicity gradients. The integrated gas metallicity of our Fornax cluster galaxies shows slightly higher metallicities (∼0.045 dex) in comparison to a control sample. In addition, we find signs of a mass and metallicity segregation from the center to the outskirts of the cluster. By comparing our Fornax cluster metallicity gradients with a control sample we find a general median offset of ∼0.04 dex/Re, with eight of our galaxies showing flatter or more positive gradients. The intermediate infallers in our Fornax sample show more positive gradients with respect to the control sample. We find no systematic difference between the gradients of recent and intermediate infallers when considering the projected distance of each galaxy to the cluster center. To identify the origin of the observed offset in the metallicity gradients, we performed a similar analysis with data from the TNG50 simulation. We identify 12 subhalos in Fornax-like clusters and compared their metallicity gradients with a control sample of field subhalos. This exercise also shows a flattening in the metallicity gradients for galaxies in Fornax-like halos, with a median offset of ∼0.05 dex/Re. We also analyzed the merger history, Mach numbers (ℳ), and ram pressure stripping of our TNG50 sample. We conclude that the observed flattening in metallicity gradients is likely due to a combination of galaxies traveling at supersonic velocities (ℳ &gt; 1), which are experiencing high ram pressure stripping and flybys.

A Twin-jet Structure Rather than Jet Rotation in the Young Stellar Object OMC 2/FIR 6b

Abstract We analyze recent high-quality Atacama Large Millimeter Array (ALMA) molecular line mapping observations of the northeast jet of the young stellar object (YSO) OMC 2/FIR 6b (HOPS-60) and find that these ALMA observations are much more likely to indicate a twin-jet structure than jet rotation, as previously hypothesized. The interpretation of the line-of-sight velocity gradient across (perpendicular to its axis) the northeast jet of Fir 6b in terms of jet rotation leads to jet-launching radii of ≃2–3 au. However, the velocities of the jets ≃100–400 km s−1 are much larger than the escape speed from these radii. We argue that the northeast jet of FIR 6b is instead compatible with a twin-jet structure, as observed in some planetary nebulae. Specifically, we find that the main, redshifted jet emanating from the central YSO is composed of two, very closely aligned, narrower jets that were launched by the central YSO at about the same time but at different inclinations with respect to the plain of the sky. This twin-jet structure removes the extreme requirement that jets with velocities similar to the escape velocity from the YSO be launched from very large radii. The YSO FIR 6b and certain planetary nebulae also share the characteristics of unequal structures and intensities of their two opposing bipolar jets. We propose that such opposing lobe asymmetries can result from a substellar binary companion on an eccentric orbit that is inclined to the accretion disk plane.

UV-SLAM: Unconstrained Line-Based SLAM Using Vanishing Points for Structural Mapping

In feature-based simultaneous localization and mapping (SLAM), line features complement the sparsity of point features, making it possible to map the surrounding environment structure. Existing approaches utilizing line features have primarily employed a measurement model that uses line re-projection. However, the direction vectors used in the 3D line mapping process cannot be corrected because the line measurement model employs only the lines’ normal vectors in the Plücker coordinate. As a result, problems like degeneracy that occur during the 3D line mapping process cannot be solved. To tackle the problem, this letter presents a UV-SLAM, which is an unconstrained line-based SLAM using vanishing points for structural mapping. This letter focuses on using structural regularities without any constraints, such as the Manhattan world assumption. For this, we use the vanishing points that can be obtained from the line features. The difference between the vanishing point observation calculated through line features in the image and the vanishing point estimation calculated through the direction vector is defined as a residual and added to the cost function of optimization-based SLAM. Furthermore, through Fisher information matrix rank analysis, we prove that vanishing point measurements guarantee a unique mapping solution. Finally, we demonstrate that the localization accuracy and mapping quality are improved compared to the state-of-the-art algorithms using public datasets.

High-precision four-dimensional hyperspectral imager integrating fluorescence spectral detection and 3D surface shape measurement.

A four-dimensional hyperspectral imager (FDHI) that combines fluorescence spectral detection and 3D surface morphology measurement is proposed. The FDHI consists of a hyperspectral line-scanner, a line structured light stereo vision system, and a line laser. The line laser is used as both the excitation light for the fluorescence and the scanning light line for the 3D profiling. At each scanning step, the system collects both fluorescent and 3D spatial data of the irradiated line region, which are fused to 4D data points based on a line mapping relationship between the datasets, and by scanning across the measurement object, a complete 4D dataset is obtained. The FDHI shows excellent performance with spatial and spectral resolution of 26.0 µm and 3 nm, respectively. The reported FDHI system and its applications provide a solution for 4D detection and analysis of fluorescent objects in meters measurement range, with advantage of high integration as two imaging modules sharing a same laser source.