spatial phase modulation
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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
Článek porovnává možnosti měření likvorové dynamiky pomocí tří různých metod magnetické rezonance: metody fázového kontrastu (Phase contrast, PC), sekvence SPAMM (Spatial modulation of magnetization) a sekvence PSIF. Principy všech metod jsou zde stručně objasněny. Jedině PC umožňuje kvantifikovat okamžitou rychlost a průtok. Výhoda sekvence PSIF spočívá v jednoduchosti měření (bez potřeby EKG) a v možnosti zobrazit větší objem zájmu (3D). Jedinou výhodou sekvence SPAMM je možnost dynamického zobrazení toku i v případě turbulentního charakteru, kdy interpretace výsledku v pnpadě PC může být složitá. Mereni byla prováděna jak na skupině zdravých dobrovolníků (10 dospělých, 10 dětí), tak s pacienty (stenóza akveduktu, stav po ventrikulostomii, syringomyelic). V případě syringomyelic byl porov¬ L Časový charakter pulzace uvnitř míšní dutiny s extramedulárním prostorem. U malých dutin (zhruba do 2 cm délky) jsme nenaměřili výraznější pohyb likvoru. U rozměrnějších kavit (mezi 2 až 10 cm) byla délka pulzní likvorové vlny kratší v intramedulámí dutině než v extramedulárním prostoru. U rozsáhlých syringomyelií (více než 10 cm) jsme většinou naměřili shodnou pulzaci uvnitř a vně míchy.
The authors compare the possibilities of assessment of the dynamics of cerebrospinal fiuid (CSF) by three different methods of magnetic resonance: phase contrast (PC), SPAMM sequence (spatial modulation of magnetization) and the PSIF sequence. The principles of all methods are briefly explained. Only PC makes quantification of the rate and flow possible. The advantage of the PSIF sequence is in the simplicity of measurement (not requiring ECG) and the possibility to visualize a larger area of interest (3D). The only advantage of sequence SPAMM is the opportunity of dynamic imaging of the flow even when it is turbulent when the interpretation of results obtained by PC may be complicated. The assessments were made in a group of healthy volunteers (10 adults, 10 children) as well as in patients (stenosis of the aqueduct, condition after ventriculostomy, syringomyelia). In syringomye¬ lia the character of the pulsation in the spinal cavity was compared with the extramedullary space. In small cavities (under 2 cm long) no marked movement of CSF was found. In larger cavities (2 to 10 cm) the lenght of the pulse CSF wave was shorter in the intramedullary cavity than in the extramedullary space. In extensive syringomyelias (more than 10 cm) usually the same pulsation was recorded inside and outside the spinal cord.
... - 4.2 Magnetic Field Gradients 192 -- 4.3 Slice Selection 193 -- 4.4 Frequency Encoding 195 -- 4.5 Phase ... ... Encoding 201 -- 4.6 Spatial Frequency Space 202 -- 4.7 Fast MRI Sequences 206 -- 4.7.1 Echo-planar Imaging ... ... Rotation Pulses 269 -- 5.7.6 Variable Angle Adiabatic Plane Rotation Pulse, BIR-4 271 -- 5.7.7 Modulation ... ... Relaxation 276 -- 5.9 Power Deposition 280 -- 5.10 Multidimensional RF Pulses 283 -- 5.11 Spectral-spatial ... ... 368 -- 7.5.2 Outer Volume Suppression and Volume -- Pre-localization 368 -- 7.5.3 Methods Utilizing Spatial ...
2nd ed. xxi, 570 s., [8] s. obr. příl. : il. ; 25 cm
... Transport 39 -- 2.2 Example MDCT Scan Workflow: Routine Non-Contrast Head 39 -- Workflows with Multiple Phases ... ... 3.1.2 Variability in ROI Measurements of CT Number 83 -- 3.2 Image Contrast 85 -- 3.3 CNR 87 -- 3.4 Spatial ... ... 134 -- Guidance for PE Studies on Pregnant Patients 139 -- 4.5.2 Shielding in Diagnostic CT: mA Modulation ... ... 233 -- 7.1.2 Beam Energy Modulation 235 -- 7.2 Practical AEC Advice 237 -- 7.3 MDCT Vendor Implementation ... ... 315 -- 103 Position and Spatial Resolution 318 -- 10.4 Position and Temporal Resolution 320 -- 10.5 ...
xv, 570 stran : ilustrace ; 26 cm
- MeSH
- diagnostické zobrazování MeSH
- počítačová rentgenová tomografie MeSH
- Publikační typ
- příručky MeSH
We report the first vibrational circular dichroism (VCD) measurement of spatial heterogeneity in a sample using infrared (IR) microsampling. Vibrational circular dichroism spectra are typically measured using a standard IR cell with an IR beam diameter of 10 mm or greater making it impossible to investigate the spatial heterogeneity of a solid film sample. We have constructed a VCD sampling assembly with either 3 mm or 1 mm spatial resolution. An XY-translation stage was used to measure spectra at different spatial locations producing IR and VCD maps of the sample. In addition, a rotating sample stage was employed using a dual photoelastic modulator (PEM) setup to suppress artifacts due to linear birefringence in solid-phase or film samples. Infrared and VCD mapping of an insulin fibril film has been carried out at both 3 and 1 mm spatial resolution, and lysozyme films were mapped at 1 mm resolution. The IR spectra of different spots vary in intensity due primarily to sample thickness. The changes in the VCD intensity across the map largely correlate to corresponding changes in the IR map. Closer inspection of the insulin map revealed changes in the relative intensities of the VCD spectra not present in the parent IR spectra, which indicated differences in the degree of supramolecular chirality of the fibrils in the various spatial regions. For lysozyme films, in addition to different degrees of supramolecular chirality, reversal of the net fibril chirality was observed. The large signal-to-noise ratio observed at 1 mm resolution implies the feasibility of further increasing the spatial resolution by one or two orders of magnitude for protein fibril film samples.
- MeSH
- amyloid analýza chemie MeSH
- artefakty MeSH
- cirkulární dichroismus metody MeSH
- inzulin analýza chemie MeSH
- muramidasa analýza chemie MeSH
- počítačové zpracování signálu MeSH
- skot MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- vibrace MeSH
- zvířata MeSH
- Check Tag
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Hatching is modulated by a combination of intrinsic and extrinsic factors. Annual killifish are adapted to complete their entire life cycle in annually desiccating habitats. Spending most of their life in the embryonic stage, they have evolved adaptations to survive desiccated conditions and match their hatching with the unpredictable onset of the aquatic phase of the pool. We examined spatial and temporal synchrony of hatching in natural populations of four species of African annual killifish (genus Nothobranchius). We compared differences and variability in hatching dates among years, regions, pools, and species and matched them with data on inundations of individual pools. RESULTS: Inundations typically coincided with peak rainfall in early January. We found considerable spatial and temporal synchrony in 1 year, but less synchrony in the other 2 years. Hatching generally occurred 0-20 days after inundation; fish at most sites hatched synchronously (<1 week) but some sites showed protracted hatching or two age cohorts. One species tended to hatch earlier than the other three. CONCLUSIONS: We suggest that hatching of annual killifish in the wild is a result of the interplay between environmental conditions and individual predisposition to respond to threshold environmental cues, ensuring effective bet-hedging against unpredictable inundation. Developmental Dynamics 246:827-837, 2017. © 2017 Wiley Periodicals, Inc.
... Guillouzo 85 -- Modulation of fibroblastic cytoskeletal features during wound healing and fibrosis -- ... ... Meyer zum Buschenfelde -- Temporal and spatial patterns of proto-oncogene, TGF-B1 and matrix-protease ... ... Sies -- Lipid peroxidation modulates constitutive collagen a^l) gene expression in cultured fibroblasts ... ... Meyer zum Buschenfelde 335 -- 44 Acute-phase proteins and liver fibrosis in the rat -- M. B. C. ... ... Smedsrpd 454 -- SECTION VI: EXTRACELLULAR MATRIX AS MODULATOR OF -- FIBROGENESIS -- The extracellular ...
xvi, 555 stran, 2 nečíslované strany obrazové přilohy : ilustrace ; 24 cm
- MeSH
- biologie buňky MeSH
- jaterní cirhóza etiologie MeSH
- molekulární biologie MeSH
- Publikační typ
- kongresy MeSH
- souborné dílo MeSH
- zprávy MeSH
- Konspekt
- Patologie. Klinická medicína
- NLK Obory
- hepatologie
- molekulární biologie, molekulární medicína
... Felici (Italy) 7 -- The homogeneous irradiation of laser targets with a dynamic plasma phase plate applying ... ... Nundy (India) 28 -- Measurement of spatial-frequency and amplitude characteristics of device for laser ... ... Eichler (Germany) 30 -- High repetition-rate modulation for high power lasers -- V. V. ... ... Chausova (Russia) 48 -- Optimization of an explosively pumped photo-dissociation iodine laser with phase ... ... Jirásek (Czech Republic) 161 -- Modeling of the all gas-phase iodine laser (AGIL) -- T. J. ...
1st ed. 209 s. ; 30 cm
- MeSH
- lasery MeSH
- Publikační typ
- abstrakt z konference MeSH
- souborné dílo MeSH
- Konspekt
- Optika
- NLK Obory
- fyzika, biofyzika
- technika
... Sheets of Cells Enclose a Sheltered Internal Environment 30 -- Cell-Cell Communication Controls the Spatial ... ... -- Active Oncogenes Have Been Isolated Directly from -- Human Tumors -- Summary -- Events in the S Phase ... ... -- During the S Phase, Clusters of Replication Forks Become Simultaneously Active on Each Chromosome ... ... -- Replication Times During the S Phase Are Correlated with Interphase Chromatin Structure -- How Is ... ... -- Germ Cells and Fertilization -- The Benefits of Sex 769 -- In Multicellular Animals the Diploid Phase ...
xxxix, 1146 s. : il., tab. ; 28 cm
- MeSH
- biologie buňky MeSH
- molekulární biologie MeSH
- Publikační typ
- monografie MeSH
- Konspekt
- Biochemie. Molekulární biologie. Biofyzika
- NLK Obory
- biologie
- cytologie, klinická cytologie
... Combinations of -- Secondary and Tertiary Structures 68 -- Structural and Functional Domains Are Modules ... ... Transport Cause Disease by Affecting Sensory Primary Cilia 780 -- Mitosis Can Be Divided into Six Phases ... ... G-\\ Cyclins Associate with S. cerevisiae CDK to Form S-Phase-Promoting Factors 874 -- XXXÜ • CONTENTS ... ... -- Degradation of the S-Phase Inhibitor Triggers DNA Replication 876 -- Multiple Cyclins Regulate the ... ... Mitosis 892 -- Repression of Gt Cyclins and a Meiosis-Specific Protein Kinase Promote Premeiotic S Phase ...
6th ed. xxxvii, 1150 s. : il., tab. ; 29 cm
- MeSH
- biologie buňky MeSH
- molekulární biologie MeSH
- Publikační typ
- monografie MeSH
- Konspekt
- Biochemie. Molekulární biologie. Biofyzika
- NLK Obory
- biologie
- cytologie, klinická cytologie
