How Do Spores Select Where to Settle?: A Holographic Motility Analysis of Ulva Zoospores on Different Surfaces

ISBN-13: 9783642172168 / Angielski / Twarda / 2011 / 178 str.

Matthias Heydt

Opis

Using digital in-line holography for the first time, this thesis has been nominated for a Springer prize and achieves a complete three-dimensional and real-time motion analysis of Ulva zoospores, both in solution and in the vicinity of different surfaces.

Spis treści

 

1             INTRODUCTION          

REFERENCES                 

2             THEORY OF HOLOGRAPHY    

2.1          PROPERTIES OF LIGHT WAVES           

2.1.1        Intensity            

2.1.2       Interference      

2.1.3        Coherence         

2.1.4       Diffraction        

2.2          HOLOGRAPHY              

2.2.1       Principle            

2.2.2       In-line holography        

2.2.3       Numerical reconstruction          

2.2.4       Resolution         

REFERENCES                 

3             STATE OF THE ART     

3.1           ALGA ULVA LINZA     

3.2          INFLUENCE OF SURFACE PROPERTIES ON SETTLEMENT AND THE ADHESION STRENGTH OF ULVA SPORES

3.2.1        Wettability       

3.2.2       Ethylene glycol containing surfaces coatings     

3.2.3       Lubricity           

3.2.4       Charge 

3.2.5       Topography      

3.3          MOTILITY OF MICROORGANISMS      

3.3.1        Hydrodynamics basics: Life at low Reynolds number

3.3.2       Properties of swimming Microorganisms            

3.3.3        Hydrodynamics interaction at solid boundaries

3.4          TRACKING IN 3D          

REFERENCES                 

4             EXPERIMENTAL DETAILS       

4.1          SETUP               

4.1.1        Holographic Microscope            

4.1.2       Wet cell             

4.1.3       Subsonic noise isolation             

4.1.4       Data acquisition program          

4.1.5       Heat isolation   

4.2          EXPERIMENTAL PROCEDURE              

4.3          TRAJECTORY ANALYSIS          

4.3.1       Reconstruction

4.3.2       Position determination

4.4         TRAJECTORY INTERPRETATION        

4.5          SURFACE POSITION DETERMINATION           

4.6         EXPERIMENTS WITH ULVA ZOOSPORES       

4.7          INVESTIGATED SURFACES     

REFERENCES                 

5             RESULTS: MOTILITY AND EXPLORATION BEHAVIOR OF ULVA ZOOSPORES           

5.1           MOTILITY OF ULVA ZOOSPORES IN SOLUTION        

5.1.1        Bulk motility: Global analysis of traces 

5.1.2        Bulk motility: Detailed motion analysis for individual traces      

5.1.2.1     Fast spore fraction         

5.1.2.2     Slow spore fraction        

5.1.3        Summary of the motility in solution      

5.1.4       Discussion of the motility in solution    

5.2          SURFACE EXPLORATION        

5.2.1        Standard settlement study         

5.2.2       Expected spore settlement during a holographic tracking experiment   

5.2.3       Settlement analysis on the investigated surfaces              

5.2.4       General exploration patterns     

5.2.4.1    Swimming pattern: Orientation

5.2.4.2    Swimming pattern: Wobbling

5.2.4.3    Swimming pattern: Gyration     

5.2.4.4    Swimming pattern: Hit and run

5.2.4.5    Swimming pattern: Spinning    

5.2.4.6    Settlement        

5.2.4.7    Swimming pattern: Hit and stick            

5.3          SUMMARY OF THE RESULTS OF THE SURFACE EXPLORATION        

5.3.1        General observations on motility for all investigated surfaces    

5.3.2       Summary of results for the exploration behavior on AWG          

5.3.3        Summary of results for the exploration behavior on PEG            

5.3.4       Summary of results for the exploration behavior on FOTS          

REFERENCES                 

6             DISCUSSION OF THE MOTILITY OF ULVA ZOOSPORES IN VICINITY TO SURFACES

6.1          OCCURRENCE AND TIME EVOLUTION OF THE EXPLORATION BEHAVIOR IN VICINITY TO DIFFERENT SURFACES 

6.2          DETERRENT PROPERTIES OF THE PEG SURFACE      

6.3          THE HIT AND STICK PATTERN AND ITS IMPORTANCE FOR THE OBSERVED HIGH AMOUNT OF SETTLEMENT ON FOTS

6.4         HYDRODYNAMIC TRAPPING OR ACTIVE EXTENDED EXPLORATION NEAR THE SURFACE?        

REFERENCES                 

7             CONCLUSION AND OUTLOOK            

REFERENCES                 

8             ACKNOWLEDGEMENT             

9             APPENDIX       

9.1          EXPLORATION BEHAVIOR ON AWG 

9.1.1        Exploration on AWG: Swimming pattern analysis           

9.1.1.1     AWG swimming pattern: Gyration         

9.1.1.2     AWG swimming pattern: Hit and run    

9.1.1.3     AWG swimming pattern: Spinning        

9.1.2       Exploration on AWG: General behavior

9.2          EXPLORATION ON PEG COATING      

9.2.1       Exploration on PEG: Swimming pattern analysis             

9.2.1.1     PEG swimming pattern: Gyration           

9.2.1.2    PEG swimming pattern: Hit and run      

9.2.1.3    Detailed description of “the unusual” spore       

9.2.2       Exploration on PEG: General behavior  

9.3          EXPLORATION ON FLUORINATED MONOLAYER (FOTS) COATING              

9.3.1       Exploration on FOTS: Swimming pattern analysis           

9.3.1.1     FOTS swimming pattern: Hit and stick 

9.3.1.2    FOTS swimming pattern: Spinning        

9.3.1.3     FOTS swimming pattern: Gyration         

9.3.2       Exploration on FOTS: General behavior

Blurb

In this thesis, Matthias Heydt applies digital in-line holography to achieve for the first time a complete three dimensional and real time motion analysis of Ulva zoospores, both in solution and in the vicinity of different surfaces. These results provide previously unknown information about the behavior and mechanism spores use to select a suitable site for settlement. This work gives deeper insight into biofouling algae and stimulates new design strategies for antifouling coatings. Furthermore, the tracking system developed during this research could be used as a new system for assessing the antifouling performance on different surfaces at very early points in time, allowing disentanglement of surface conditioning and interaction of spores with pristine chemistries.