Spatial light modulators have become an essential tool for advanced microscopy, enabling breakthroughs in 3D, phase, and super-resolution imaging. However, continuous spatial-light modulation that is capable of capturing sub-millisecond microscopic motion without diffraction artifacts and polarization dependence is challenging. Here we present a photothermal spatial light modulator (PT-SLM) enabling fast phase imaging for nanoscopic 3D reconstruction. The PT-SLM can generate a step-like wavefront change, free of diffraction artifacts, with a high transmittance and a modulation efficiency independent of light polarization. We achieve a phase-shift > π and a response time as short as 70 µs with a theoretical limit in the sub microsecond range. We used the PT-SLM to perform quantitative phase imaging of sub-diffractional species to decipher the 3D nanoscopic displacement of microtubules and study the trajectory of a diffusive microtubule-associated protein, providing insights into the mechanism of protein navigation through a complex microtubule network.

• MeSH
• časové faktory MeSH
• interferenční mikroskopie metody   statistika a číselné údaje   MeSH
• kovové nanočástice ultrastruktura   MeSH
• lidé MeSH
• mikroskopie atomárních sil MeSH
• mikroskopie fázově kontrastní metody   statistika a číselné údaje   MeSH
• mikrotubuly metabolismus   ultrastruktura   MeSH
• nanotechnologie MeSH
• nanotrubičky ultrastruktura   MeSH
• optické jevy MeSH
• počítačová simulace MeSH
• proteiny asociované s mikrotubuly metabolismus   MeSH
• proteiny buněčného cyklu metabolismus   MeSH
• Schizosaccharomyces pombe - proteiny metabolismus   MeSH
• světlo MeSH
• tubulin metabolismus   MeSH
• zlato MeSH
• zobrazování trojrozměrné metody   statistika a číselné údaje   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• Ase1 protein, S pombe MeSH Prohlížeč
• PRC1 protein, human MeSH Prohlížeč
• proteiny asociované s mikrotubuly MeSH
• proteiny buněčného cyklu MeSH
• Schizosaccharomyces pombe - proteiny MeSH
• tubulin MeSH
• zlato MeSH

The use of 3D visualization technologies has increased rapidly in many applied fields, including geovisualization, and has been researched from many different perspectives. However, the findings for the benefits of 3D visualization, especially in stereoscopic 3D forms, remain inconclusive and disputed. Stereoscopic "real" 3D visualization was proposed as encouraging the visual perception of shapes and volume of displayed content yet criticised as problematic and limited in a number of ways, particularly in visual discomfort and increased response time in tasks. In order to assess the potential of real 3D visualization for geo-applications, 91 participants were engaged in this study to work with digital terrain models in different 3D settings. The researchers examined the effectivity of stereoscopic real 3D visualization compared to monoscopic 3D (or pseudo 3D) visualization under static and interactive conditions and applied three tasks with experimental stimuli representing different geo-related phenomena, i.e. objects in the terrain, flat areas marked in the terrain and terrain elevation profiles. The authors explored the significant effects of real 3D visualization and interactivity factors in terms of response time and correctness. Researchers observed that the option to interact (t = -10.849, p < 0.001) with a virtual terrain and its depiction with real 3D visualization (t = 4.64, p < 0.001) extended the participants' response times. Counterintuitively, the data demonstrated that the static condition increased response correctness (z = 5.38, p < 0.001). Regarding detailed analysis of data, an interactivity factor was proposed as a potential substitute for real 3D visualization in 3D geographical tasks.

• MeSH
• dospělí MeSH
• geografická kartografie * MeSH
• lidé středního věku MeSH
• lidé MeSH
• lineární modely MeSH
• mladý dospělý MeSH
• počítačová grafika MeSH
• reakční čas MeSH
• zeměpis metody   statistika a číselné údaje   MeSH
• zobrazování trojrozměrné metody   statistika a číselné údaje   MeSH
• zraková percepce MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

3D imaging approaches based on X-ray microcomputed tomography (microCT) have become increasingly accessible with advancements in methods, instruments and expertise. The synergy of material and life sciences has impacted biomedical research by proposing new tools for investigation. However, data sharing remains challenging as microCT files are usually in the range of gigabytes and require specific and expensive software for rendering and interpretation. Here, we provide an advanced method for visualisation and interpretation of microCT data with small file formats, readable on all operating systems, using freely available Portable Document Format (PDF) software. Our method is based on the conversion of volumetric data into interactive 3D PDF, allowing rotation, movement, magnification and setting modifications of objects, thus providing an intuitive approach to analyse structures in a 3D context. We describe the complete pipeline from data acquisition, data processing and compression, to 3D PDF formatting on an example of craniofacial anatomical morphology in the mouse embryo. Our procedure is widely applicable in biological research and can be used as a framework to analyse volumetric data from any research field relying on 3D rendering and CT-biomedical imaging.

• MeSH
• anatomické modely MeSH
• automatizované zpracování dat MeSH
• komprese dat statistika a číselné údaje   MeSH
• lebka anatomie a histologie   embryologie   MeSH
• myši MeSH
• obličejové kosti anatomie a histologie   embryologie   MeSH
• rentgenová mikrotomografie statistika a číselné údaje   MeSH
• rentgenový obraz - interpretace počítačová MeSH
• šíření informací metody   MeSH
• software * MeSH
• zobrazování trojrozměrné statistika a číselné údaje   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The paper deals with modeling the liver perfusion intended to improve quantitative analysis of the tissue scans provided by the contrast-enhanced computed tomography (CT). For this purpose, we developed a model of dynamic transport of the contrast fluid through the hierarchies of the perfusion trees. Conceptually, computed time-space distributions of the so-called tissue density can be compared with the measured data obtained from CT; such a modeling feedback can be used for model parameter identification. The blood flow is characterized at several scales for which different models are used. Flows in upper hierarchies represented by larger branching vessels are described using simple 1D models based on the Bernoulli equation extended by correction terms to respect the local pressure losses. To describe flows in smaller vessels and in the tissue parenchyma, we propose a 3D continuum model of porous medium defined in terms of hierarchically matched compartments characterized by hydraulic permeabilities. The 1D models corresponding to the portal and hepatic veins are coupled with the 3D model through point sources, or sinks. The contrast fluid saturation is governed by transport equations adapted for the 1D and 3D flow models. The complex perfusion model has been implemented using the finite element and finite volume methods. We report numerical examples computed for anatomically relevant geometries of the liver organ and of the principal vascular trees. The simulated tissue density corresponding to the CT examination output reflects a pathology modeled as a localized permeability deficiency.

• Klíčová slova
• Bernoulli equation, Darcy flow, Dynamic contrast-enhanced computed tomography, Liver perfusion, Porous media, Transport equation,
• MeSH
• analýza metodou konečných prvků MeSH
• biologické modely MeSH
• jaterní oběh * fyziologie   MeSH
• játra krevní zásobení   diagnostické zobrazování   MeSH
• kontrastní látky farmakokinetika   MeSH
• lidé MeSH
• matematické pojmy MeSH
• počítačová rentgenová tomografie statistika a číselné údaje   MeSH
• počítačová simulace MeSH
• poréznost MeSH
• vylepšení rentgenového snímku metody   MeSH
• zobrazování trojrozměrné statistika a číselné údaje   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kontrastní látky MeSH

INTRODUCTION: The aim of this study was to determine the reproducibility and accuracy of linear measurements on 2 types of dental models derived from cone-beam computed tomography (CBCT) scans: CBCT images, and Anatomodels (InVivoDental, San Jose, Calif); these were compared with digital models generated from dental impressions (Digimodels; Orthoproof, Nieuwegein, The Netherlands). The Digimodels were used as the reference standard. METHODS: The 3 types of digital models were made from 10 subjects. Four examiners repeated 37 linear tooth and arch measurements 10 times. Paired t tests and the intraclass correlation coefficient were performed to determine the reproducibility and accuracy of the measurements. RESULTS: The CBCT images showed significantly smaller intraclass correlation coefficient values and larger duplicate measurement errors compared with the corresponding values for Digimodels and Anatomodels. The average difference between measurements on CBCT images and Digimodels ranged from -0.4 to 1.65 mm, with limits of agreement values up to 1.3 mm for crown-width measurements. The average difference between Anatomodels and Digimodels ranged from -0.42 to 0.84 mm with limits of agreement values up to 1.65 mm. CONCLUSIONS: Statistically significant differences between measurements on Digimodels and Anatomodels, and between Digimodels and CBCT images, were found. Although the mean differences might be clinically acceptable, the random errors were relatively large compared with corresponding measurements reported in the literature for both Anatomodels and CBCT images, and might be clinically important. Therefore, with the CBCT settings used in this study, measurements made directly on CBCT images and Anatomodels are not as accurate as measurements on Digimodels.

• MeSH
• kefalometrie statistika a číselné údaje   MeSH
• lidé MeSH
• počítačová tomografie s kuželovým svazkem statistika a číselné údaje   MeSH
• počítačové zpracování obrazu statistika a číselné údaje   MeSH
• povrchové vlastnosti MeSH
• reprodukovatelnost výsledků MeSH
• software MeSH
• zobrazování trojrozměrné statistika a číselné údaje   MeSH
• zubní korunka (anatomie) anatomie a histologie   MeSH
• zubní modely * MeSH
• zubní oblouk anatomie a histologie   MeSH
• zubní technika otisková statistika a číselné údaje   MeSH
• zuby anatomie a histologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH

INTRODUCTION: The process of fabricating physical medical skull models requires many steps, each of which is a potential source of geometric error. The aim of this study was to demonstrate inaccuracies and differences caused by DICOM to STL conversion in additively manufactured medical skull models. MATERIAL AND METHODS: Three different institutes were requested to perform an automatic reconstruction from an identical DICOM data set of a patients undergoing tumour surgery into an STL file format using their software of preference. The acquired digitized STL data sets were assessed and compared and subsequently used to fabricate physical medical skull models. The three fabricated skull models were then scanned, and differences in the model geometries were assessed using established CAD inspection software methods. RESULTS: A large variation was noted in size and anatomical geometries of the three physical skull models fabricated from an identical (or "a single") DICOM data set. CONCLUSIONS: A medical skull model of the same individual can vary markedly depending on the DICOM to STL conversion software and the technical parameters used. Clinicians should be aware of this inaccuracy in certain applications.

• Klíčová slova
• Additive-manufacturing, Bio-modelling, CBCT, DICOM, STL,
• MeSH
• algoritmy MeSH
• anatomické modely * MeSH
• design s pomocí počítače statistika a číselné údaje   MeSH
• kefalometrie statistika a číselné údaje   MeSH
• lebka anatomie a histologie   MeSH
• lidé MeSH
• mandibula anatomie a histologie   MeSH
• nosní dutina anatomie a histologie   MeSH
• orbita anatomie a histologie   MeSH
• počítačová tomografie s kuželovým svazkem statistika a číselné údaje   MeSH
• počítačové zpracování obrazu statistika a číselné údaje   MeSH
• povrchové vlastnosti MeSH
• radiologické informační systémy statistika a číselné údaje   MeSH
• sinus maxillaris anatomie a histologie   MeSH
• software MeSH
• zobrazování trojrozměrné statistika a číselné údaje   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH

Current models of the vocal folds derive their shape from approximate information rather than from exactly measured data. The objective of this study was to obtain detailed measurements on the geometry of human vocal folds and the glottal channel in phonatory position. A non-destructive casting methodology was developed to capture the vocal fold shape from excised human larynges on both medial and superior surfaces. Two female larynges, each in two different phonatory configurations corresponding to low and high fundamental frequency of the vocal fold vibrations, were measured. A coordinate measuring machine was used to digitize the casts yielding 3D computer models of the vocal fold shape. The coronal sections were located in the models, extracted and fitted by piecewise-defined cubic functions allowing a mathematical expression of the 2D shape of the glottal channel. Left-right differences between the cross-sectional shapes of the vocal folds were found in both the larynges.

• MeSH
• biologické modely * MeSH
• biomechanika metody   MeSH
• glottis anatomie a histologie   fyziologie   MeSH
• hlas fyziologie   MeSH
• hlasové řasy anatomie a histologie   fyziologie   MeSH
• lidé MeSH
• senioři MeSH
• zobrazování trojrozměrné statistika a číselné údaje   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH