Vision guided automation for intra-cytoplasmic sperm injection

Biological cell injection is an effective technique in which a foreign material is directly introduced into the target cell. Intracytoplasmic Sperm Injection (ICSI) is a microinjection technique which is used for infertility treatment. In this technique, a single sperm cell is directly injected into an oocyte using micropipettes. The operations in this application are manually controlled by an embryologist and more importantly, this reduces the accuracy, repeatability, and consistency of the operation. Therefore, the full automation is a prerequisite for microinjection operations, particularly in ICSI application. This thesis focuses on enhancing the microinjection procedure by developing vision-guided processes prior to and during the operation. Initially, a vision-controlled technique was proposed to align the injection and holding pipettes in three orthogonal axes which is essential for successful microinjection. To conduct reliable injection, the vibrational displacement of the injection pipette’s tip needs to be evaluated and improved before the operations continue further. A novel vision-based sensor was developed to measure the displacement changes at the tip in three orthogonal axes. By employing the developed vision sensor, the effect of injection speed on vibrational displacement creation was analysed to determine the value of various injection parameters, such as force fluctuation, and penetration force on cell damages. An ultimate automation task is required in microinjection to position the randomly located biological cell within the Petri dish to the system’s field of view. The proposed technique fills a gap in the literature by proposing a real-time cell recognising and positioning system that can be employed with different types of biological cells at various maturation stages, as well as with different microscope types that are being used in microinjection applications

The NASA SBIR product catalog

The purpose of this catalog is to assist small business firms in making the community aware of products emerging from their efforts in the Small Business Innovation Research (SBIR) program. It contains descriptions of some products that have advanced into Phase 3 and others that are identified as prospective products. Both lists of products in this catalog are based on information supplied by NASA SBIR contractors in responding to an invitation to be represented in this document. Generally, all products suggested by the small firms were included in order to meet the goals of information exchange for SBIR results. Of the 444 SBIR contractors NASA queried, 137 provided information on 219 products. The catalog presents the product information in the technology areas listed in the table of contents. Within each area, the products are listed in alphabetical order by product name and are given identifying numbers. Also included is an alphabetical listing of the companies that have products described. This listing cross-references the product list and provides information on the business activity of each firm. In addition, there are three indexes: one a list of firms by states, one that lists the products according to NASA Centers that managed the SBIR projects, and one that lists the products by the relevant Technical Topics utilized in NASA's annual program solicitation under which each SBIR project was selected

Remote refocusing light-sheet fluorescence microscopy for high-speed 2D and 3D imaging of calcium dynamics in cardiomyocytes

The high prevalence and poor prognosis of heart failure are two key drivers for research into cardiac electrophysiology and regeneration. Dyssynchrony in calcium release and loss of structural organization within individual cardiomyocytes (CM) has been linked to reduced contractile strength and arrhythmia. Correlating calcium dynamics and cell microstructure requires multidimensional imaging with high spatiotemporal resolution. In light-sheet fluorescence microscopy (LSFM), selective plane illumination enables fast optically sectioned imaging with lower phototoxicity, making it suitable for imaging subcellular dynamics. In this work, a custom remote refocusing LSFM system is applied to studying calcium dynamics in isolated CM, cardiac cell cultures and tissue slices. The spatial resolution of the LSFM system was modelled and experimentally characterized. Simulation of the illumination path in Zemax was used to estimate the light-sheet beam waist and confocal parameter. Automated MATLAB-based image analysis was used to quantify the optical sectioning and the 3D point spread function using Gaussian fitting of bead image intensity distributions. The results demonstrated improved and more uniform axial resolution and optical sectioning with the tighter focused beam used for axially swept light-sheet microscopy. High-speed dual-channel LSFM was used for 2D imaging of calcium dynamics in correlation with the t-tubule structure in left and right ventricle cardiomyocytes at 395 fps. The high spatio-temporal resolution enabled the characterization of calcium sparks. The use of para-nitro-blebbistatin (NBleb), a non-phototoxic, low fluorescence contraction uncoupler, allowed 2D-mapping of the spatial dyssynchrony of calcium transient development across the cell. Finally, aberration-free remote refocusing was used for high-speed volumetric imaging of calcium dynamics in human induced pluripotent stem-cell derived cardiomyocytes (hiPSC-CM) and their co-culture with adult-CM. 3D-imaging at up to 8 Hz demonstrated the synchronization of calcium transients in co-culture, with increased coupling with longer co-culture duration, uninhibited by motion uncoupling with NBleb.Open Acces