spatial positioning
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2022 ◽  
Vol 11 (1) ◽  
pp. 68
Author(s):  
Peng Ye ◽  
Xueying Zhang ◽  
Chunju Zhang ◽  
Yulong Dang

In the big data era, spatial positioning based on location description is the foundation to the intelligent transformation of location-based-services. To solve the problem of vagueness in location description in different contexts, this paper proposes a positioning method based on supervaluation semantics. Firstly, through combing the laws of human spatial cognition, the types of elements that people pay attention to in location description are clarified. On this basis, the source of vagueness in the location description and its embodiment in the expression form of each element are analyzed from multiple levels. Secondly, the positioning model is constructed from the following three aspects: spatial object, distance relation and direction relation. The contexts of multiple location description are super-valued, respectively, while the threshold of observations is obtained from the context semantics. Thus, the precisification of location description is realized for positioning. Thirdly, a question-answering system is designed to the collect contexts of location description, and a case study on the method is conducted. The case can verify the transformation of a set of users’ viewpoints on spatial cognition into the real-world spatial scope, to realize the representation of vague location description in the geographic information system. The result shows that the method proposed in the paper breaks through the traditional vagueness modeling, which only focuses on spatial relationship, and enhances the interpretability of semantics of vague location description. Moreover, supervaluation semantics can obtain the precisification results of vague location description in different situations, and the positioning localities are more suitable to individual subjective cognition.


2021 ◽  
Author(s):  
Daniele Pirone ◽  
Daniele Sirico ◽  
Lisa Miccio ◽  
Vittorio Bianco ◽  
Martina Mugnano ◽  
...  

The most recent discoveries in the biochemical field are highlighting the increasingly important role of lipid droplets (LDs) in several regulatory mechanisms in living cells. LDs are dynamic organelles and therefore their complete characterization in terms of number, size, spatial positioning and relative distribution in the cell volume can shed light on the roles played by LDs. Until now, fluorescence microscopy and transmission electron microscopy are assessed as the gold standard methods for identifying LDs due to their high sensitivity and specificity. However, such methods generally only provide 2D assays and partial measurements. Furthermore, both can be destructive and with low productivity, thus limiting analysis of large cell numbers in a sample. Here we demonstrate for the first time the capability of 3D visualization and the full LD characterization in high-throughput with a tomographic phase-contrast flow-cytometer, by using ovarian cancer cells and monocyte cell lines as models. A strategy for retrieving significant parameters on spatial correlations and LD 3D positioning inside each cell volume is reported. The information gathered by this new method could allow more in depth understanding and lead to new discoveries on how LDs are correlated to cellular functions.


Author(s):  
Yongjia Xu ◽  
Yuemin Wang ◽  
Feng Gao ◽  
Xiangqian Jiang

AbstractAccurate and fast three-dimensional (3D) measurement for industrial products/components designed to possess 3D structured shapes is a key driver for improved productivity. However, challenges for current techniques are considerable to measure structured specular surfaces. A technique named segmentation phase measuring deflectometry (SPMD) is proposed in this paper, which enables structured specular surfaces to be measured with high accuracy in one setup. Concept of segmentation in topology is introduced into phase measuring deflectometry, which separates a surface with complex structures into continuous segments. Each segment can be reconstructed based on gradient information to achieve good form accuracy, and all reconstructed segments can be fused into a whole 3D strucutred form result based on their absolute spatial positioning data. Here, we propose and discuss the principle of SPMD, a segmentation technique to separate a strucured surface into segments, a spatial positioning technique to obtain absolute position of the segments, and a data fusion strategy to fuse all reconstructed segments. Experimental results show SPMD can achieve nanometer level accuracy for form measurement of continuous segments by comparing with stylus profilometer, which is significantly higher than the accuracy of direct phase measuring deflectometry. Meanwhile, SPMD has micron level spatial positioning accuracy for structures by measuring two specular steps and comparing with coordinate measuring machine, which differentiates this technique from gradient-based phase measuring deflectometry that extends measurement capability from continuous specular surfaces to complex structured specular surfaces. Compared with the existing measurement techniques, SPMD significantly improved the convenience and ability to measure freeform and structured specular surfaces with the advantages of high measurement accuracy, fast measurement, and potential application for embedded measurement.


Author(s):  
Mehmet Oguz Gok ◽  
Natalie Ortiz Speer ◽  
W. Mike Henne ◽  
Jonathan R. Friedman

The asymmetric distribution of phospholipids in membranes is a fundamental principle of cellular compartmentalization and organization. Phosphatidylethanolamine (PE), a nonbilayer phospholipid that contributes to organelle shape and function, is synthesized at several subcellular localizations via semi-redundant pathways. Previously, we demonstrated in budding yeast that the PE synthase Psd1, which primarily operates on the mitochondrial inner membrane, is additionally targeted to the ER. While ER-localized Psd1 is required to support cellular growth in the absence of redundant pathways, its physiological function is unclear. We now demonstrate that ER-localized Psd1 sub-localizes on the ER to lipid droplet (LD) attachment sites and show it is specifically required for normal LD formation. We also find that the role of phosphatidylserine decarboxylase (PSD) enzymes in LD formation is conserved in other organisms. Thus, we have identified PSD enzymes as novel regulators of LDs and demonstrate that both mitochondria and LDs in yeast are organized and shaped by the spatial positioning of a single PE synthesis enzyme.


Cancers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 5860
Author(s):  
Concetta Federico ◽  
Francesca Bruno ◽  
Denise Ragusa ◽  
Craig S. Clements ◽  
Desiree Brancato ◽  
...  

The last decade has seen significant progress in understanding how the genome is organized spatially within interphase nuclei. Recent analyses have confirmed earlier molecular cytogenetic studies on chromosome positioning within interphase nuclei and provided new information about the topologically associated domains (TADs). Examining the nuances of how genomes are organized within interphase nuclei will provide information fundamental to understanding gene regulation and expression in health and disease. Indeed, the radial spatial positioning of individual gene loci within nuclei has been associated with up- and down-regulation of specific genes, and disruption of normal genome organization within nuclei will result in compromised cellular health. In cancer cells, where reorganization of the nuclear architecture may occur in the presence of chromosomal rearrangements such as translocations, inversions, or deletions, gene repositioning can change their expression. To date, very few studies have focused on radial gene positioning and the correlation to gene expression in cancers. Further investigations would improve our understanding of the biological mechanisms at the basis of cancer and, in particular, in leukemia initiation and progression, especially in those cases where the molecular consequences of chromosomal rearrangements are still unclear. In this review, we summarize the main milestones in the field of genome organization in the nucleus and the alterations to this organization that can lead to cancer diseases.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Yi Huang ◽  
Mengyi Wang ◽  
Qianqian Qiu ◽  
Lizhi Miao ◽  
Haiping Zhang ◽  
...  

Electromagnetic geographic environment is closely related to human life. With continuous popularization of public infrastructures and daily electronic instruments, such as electric power communication systems and household appliances, electromagnetic radiation sources have increased sharply in the geographic environment, which leads to increasingly serious electromagnetic radiation pollution. Thus, it is significant to monitor, evaluate, and analyze the electromagnetic radiation condition and explore its changing law in the environment. However, the traditional monitoring method can only detect anomalies within certain frequencies in the fixed stations. To fill this gap, this research first develops a vehicle-mounted electromagnetic environment monitoring system to collect both spatial positioning data and electromagnetic data of the whole frequency range. The acquired data are then used to construct the location-based frequency-intensity curve to reflect the variation of electromagnetic radiation at different frequency ranges. On this basis, a curve similarity measurement method is introduced to analyze the similarity of different curves, which is effective to diagnose time-varying sources from both global and local perspectives. This research provides a real-time mobile monitoring method, which is significant to know the dynamic variation of local electromagnetic environment and promotes subsequent comprehensive geographic analyses.


2021 ◽  
Author(s):  
Ajay S. Labade ◽  
Adwait Salvi ◽  
Saswati Kar ◽  
Krishanpal Karmodiya ◽  
Kundan Sengupta

Nucleoporins regulate nuclear transport and are also involved in DNA damage, repair, cell cycle, chromatin organization, and gene expression. Here, we studied the role of nucleoporin Nup93 and the chromatin organizer CTCF in regulating HOXA expression during differentiation. ChIP sequencing revealed a significant overlap between Nup93 and CTCF peaks. Interestingly, Nup93 and CTCF are associated with the 3' and 5′HOXA genes respectively. Depletions of Nup93 and CTCF antagonistically modulate expression levels of 3′and 5′HOXA genes in undifferentiated NT2/D1 cells. Nup93 also regulates the localization of the HOXA gene locus, which disengages from the nuclear periphery upon Nup93 but not CTCF depletion, consistent with its upregulation. The dynamic association of Nup93 and CTCF with the HOXA locus during differentiation correlates with its spatial positioning and expression. While Nup93 tethers the HOXA locus to the nuclear periphery, CTCF potentially regulates looping of the HOXA gene cluster in a temporal manner. In summary, Nup93 and CTCF complement one another in modulating the spatiotemporal dynamics and function of the HOXA gene locus during differentiation.


2021 ◽  
Vol 29 (6) ◽  
pp. 16-19
Author(s):  
George Emanuel ◽  
Jiang He

Abstract:The structure and organization of cells within organs is essential to their function, but nowhere in the body is this more spectacular than the brain. There, sprawling, snowflake-like neurons have grown into a precise arrangement, reaching out to neighboring cells to form neural circuits. Communication within neural circuits, made possible by spatial positioning, forms the basis of our physiology. Recently, a high-resolution cell atlas generated by MERFISH (multiplex error-robust fluorescence in situ hybridization) technology has mapped this spectacular organ with unmatched resolution, depth, and scale. The atlas catalogs cells as they exist in the intact biological system and will allow us to learn more about rare cell types and sparsely expressed cell signaling receptors fundamental to health and disease.


2021 ◽  
Vol 2069 (1) ◽  
pp. 012220
Author(s):  
D Heincis ◽  
J Telicko ◽  
A Jakovics

Abstract As solar panel technologies become more and more popular and are increasingly used in nearly zero-energy building solutions, one must make sure that the panels are able to achieve performance indicators similar to those determined by manufacturers under standard testing in real-world conditions. To determine the efficiency of poly- and monocrystalline panels, depending on their spatial orientation and other parameters, a set of test panels was installed in Riga, Latvia in 2018 for long-term monitoring of their power output. This article summarizes the results for the first two years. In the autumn of the second year of monitoring, temperature sensors were installed on the solar panels to study the effects of temperature on panel’s efficiency. The data show that the panel’s spatial positioning is a crucial element affecting the amount of energy produced, although the type of panels and climate conditions are also important.


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