Shape restoration of nonlinear distorted images

Author(s):  
Seong-Whan Lee ◽  
Eun-Soon Kim
Keyword(s):  
Cancers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1119
Author(s):  
Ivonne Nel ◽  
Erik W. Morawetz ◽  
Dimitrij Tschodu ◽  
Josef A. Käs ◽  
Bahriye Aktas

Circulating tumor cells (CTCs) are a potential predictive surrogate marker for disease monitoring. Due to the sparse knowledge about their phenotype and its changes during cancer progression and treatment response, CTC isolation remains challenging. Here we focused on the mechanical characterization of circulating non-hematopoietic cells from breast cancer patients to evaluate its utility for CTC detection. For proof of premise, we used healthy peripheral blood mononuclear cells (PBMCs), human MDA-MB 231 breast cancer cells and human HL-60 leukemia cells to create a CTC model system. For translational experiments CD45 negative cells—possible CTCs—were isolated from blood samples of patients with mamma carcinoma. Cells were mechanically characterized in the optical stretcher (OS). Active and passive cell mechanical data were related with physiological descriptors by a random forest (RF) classifier to identify cell type specific properties. Cancer cells were well distinguishable from PBMC in cell line tests. Analysis of clinical samples revealed that in PBMC the elliptic deformation was significantly increased compared to non-hematopoietic cells. Interestingly, non-hematopoietic cells showed significantly higher shape restoration. Based on Kelvin–Voigt modeling, the RF algorithm revealed that elliptic deformation and shape restoration were crucial parameters and that the OS discriminated non-hematopoietic cells from PBMC with an accuracy of 0.69, a sensitivity of 0.74, and specificity of 0.63. The CD45 negative cell population in the blood of breast cancer patients is mechanically distinguishable from healthy PBMC. Together with cell morphology, the mechanical fingerprint might be an appropriate tool for marker-free CTC detection.


2021 ◽  
Author(s):  
Nainy Goel ◽  
Kanika Dhiman ◽  
Nidhi Kalidas ◽  
Anwesha Mukhopadhyay ◽  
Ashish ◽  
...  

AbstractArtemisinin-resistant mutations in PfKelch13 identified worldwide are mostly confined to its BTB/POZ and KRP domains. To date, only two crystal structures of the BTB/POZ-KRP domains as tight dimers are available, which limits structure-based interpretations of its functionality. Our solution Small-Angle X-ray Scattering (SAXS) data driven shape restoration of larger length of protein brought forth that: i) PfKelch13 forms a stable hexamer in P6 symmetry, ii) interactions of the N-termini drive the hexameric assembly, and iii) the six KRP domains project independently in space, forming a cauldron-like architecture. While artemisinin-sensitive mutant A578S packed like the wild-type, hexameric assemblies of dominant artemisinin-resistant mutant proteins R539T and C580Y displayed detectable differences in spatial positioning of their BTB/POZ-KRP domains. Lastly, mapping of mutations known to enable artemisinin resistance explained that most mutations exist mainly in these domains because they are non-detrimental to assembly of mutant PfKelch13 and yet can alter the flux of downstream events essential for susceptibility to artemisinin.


2009 ◽  
Vol 2 (1) ◽  
Author(s):  
Kai Xu ◽  
Nabil Simaan

This paper presents a novel and unified analytic formulation for kinematics, statics, and shape restoration of multiple-backbone continuum robots. These robots achieve actuation redundancy by independently pulling and pushing three backbones to carry out a bending motion of two-degrees-of-freedom (DoF). A solution framework based on constraints of geometric compatibility and static equilibrium is derived using elliptic integrals. This framework allows the investigation of the effects of different external loads and actuation redundancy resolutions on the shape variations in these continuum robots. The simulation and experimental validation results show that these continuum robots bend into an exact circular shape for one particular actuation resolution. This provides a proof to the ubiquitously accepted circular-shape assumption in deriving kinematics for continuum robots. The shape variations due to various actuation redundancy resolutions are also investigated. The simulation results show that these continuum robots have the ability to redistribute loads among their backbones without introducing significant shape variations. A strategy for partially restoring the shape of the externally loaded continuum robots is proposed. The simulation results show that either the tip orientation or the tip position can be successfully restored.


2006 ◽  
Vol 2006.14 (0) ◽  
pp. 33-34
Author(s):  
Nobuo SHIRAISHI ◽  
Shu MINAKUCHI ◽  
Yoji OKABE ◽  
Nobuo Takeda ◽  
Dong-Yeul SONG

Langmuir ◽  
2017 ◽  
Vol 33 (24) ◽  
pp. 6182-6191 ◽  
Author(s):  
Vickramjeet Singh ◽  
Cyuan-Jhang Wu ◽  
Yu-Jane Sheng ◽  
Heng-Kwong Tsao
Keyword(s):  

Author(s):  
Min Lu ◽  
Bo Zheng ◽  
Jun Takamatsu ◽  
Ko Nishino ◽  
Katsushi Ikeuchi

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