An optimised transformation protocol for Anthoceros agrestis and three more hornwort species

Land plants comprise two large monophyletic lineages, the vascular plants and the bryophytes, which diverged from their most recent common ancestor approximately 480 million years ago. Of the three lineages of bryophytes, only the mosses and the liverworts are systematically investigated, while the hornworts are understudied. Despite their importance for understanding fundamental questions of land plant evolution, they only recently became amenable to experimental investigation, with Anthoceros agrestis being developed as a hornwort model system. Availability of a high-quality genome assembly and a recently developed genetic transformation technique makes A. agrestis an attractive model species for hornworts. Here we describe an updated and optimised transformation protocol for A. agrestis which can be successfully used to genetically modify one more strain of A. agrestis and three more hornwort species, Anthoceros punctatus, Leiosporoceros dussi and Phaeoceros carolinianus. The new transformation method is less laborious, faster and results in the generation of greatly increased numbers of transformants compared to the previous method. We have also developed a new selection marker for transformation. Finally, we report the development of a set of different cellular localisation signal peptides for hornworts providing new tools to better understand hornwort cell biology

Image processing and control of a programmable spatial light modulator for spatial beam shaping

Abstract not provide

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

200W, 350Fs Fiber Cpa System Enabled By Chirped-Volume-Bragg-Gratings And Chirally-Coupled-Core Fiber Technology

Fiber-CPA-laser-systems are an extremely promising technology for generating ultrashort (fs-scale) pulses at high average-powers (hundreds-of-Watts to kW) while still producing diffraction-limited beams and being compact and robust compared to bulk-solid-state systems. Two obstacles still must be overcome to realize this potential, however. First, there is a need for stretchers and compressors that can yield long stretched pulse-durations (hundreds-of-ps to nanoseconds) and can handle high-energies and average-powers, yet are still simple and compact, so as to not offset the benefits of fibers. Secondly, large-core-fibers are needed for amplifiers and other components that are robustly singlemode. In this work, we present an Yb-fiber-CPA-system based on two novel technologies to overcome the aforementioned problems. Chirped-volume-Bragg-gratings (CVBGs), slabs of photo-thermo-refractive glass of cmscale with a quasi-periodic longitudinal index-of-refraction, are used for the stretcher and compressor. Their compactness and simplicity makes them compatible with fiber-laser benefits, and have excellent power handling capabilities are. Chirally-coupled-core (CCC) fibers, which have large core diameters (35μm here), yet are robustly single mode and can be coiled and spliced, are used for the power-amplifiers. Using these technologies, a system producing a record 200W of power (130W compressed) with 350fs pulse durations is demonstrated, and the potential kW-level-scaling is explored. © 2010 Copyright SPIE - The International Society for Optical Engineering

Centrosome Amplification Is a Potential Molecular Target in Paediatric Acute Lymphoblastic Leukemia

B-cell acute lymphoblastic leukemia (B-ALL) is the most common form of cancer in children. Current treatments deliver a high survival rate, but often cause harmful and enduring side effects. New treatments are needed to address this clinical challenge and reduce relapse and long-term effects in children. This study investigates the centrosome clustering pathway as a target for cancer treatments in children with B-ALL. Cancer cells often have enlarged or extra centrosomes and require the centrosome clustering pathway to progress through cell division successfully. Our data reveals that when the centrosome clustering pathway is disrupted in B-ALL cells it causes cell death and produces a population of damaged refractory cells. The refractory cells have markers that make them more visible to the immune system and are therefore more easily targeted by immune-based therapies. Acute lymphoblastic leukemia (ALL) is the most common form of cancer in children, with most cases arising from fetal B cell precursor, termed B-ALL. Here, we use immunofluorescence analysis of B-ALL cells to identify centrosome amplification events that require the centrosome clustering pathway to successfully complete mitosis. Our data reveals that primary human B-ALL cells and immortal B-ALL cell lines from both human and mouse sources show defective bipolar spindle formation, abnormal mitotic progression, and cell death following treatment with centrosome clustering inhibitors (CCI). We demonstrate that CCI-refractory B-ALL cells exhibit markers for increased genomic instability, including DNA damage and micronuclei, as well as activation of the cyclic GMP–AMP synthase (cGAS)-nuclear factor kappa B (NF-κB) signalling pathway. Our analysis of cGAS knock-down B-ALL clones implicates cGAS in the sensitivity of B-ALL cells to CCI treatment. Due to its integral function and specificity to cancer cells, the centrosome clustering pathway presents a powerful molecular target for cancer treatment while mitigating the risk to healthy cells.Medicine, Faculty ofNon UBCPediatrics, Department ofReviewedFacultyResearcherUnknow