Airborne imaging for heritage documentation using the Fotokite tethered flying camera

Since the beginning of aerial photography, researchers used all kinds of devices (from pigeons, kites, poles, and balloons to rockets) to take still cameras aloft and remotely gather aerial imagery. To date, many of these unmanned devices are still used for what has been referred to as Low-Altitude Aerial Photography or LAAP. In addition to these more traditional camera platforms, radio-controlled (multi-)copter platforms have recently added a new aspect to LAAP. Although model airplanes have been around for several decades, the decreasing cost, increasing functionality and stability of ready-to-fly multi-copter systems has proliferated their use among non-hobbyists. As such, they became a very popular tool for aerial imaging. The overwhelming amount of currently available brands and types (heli-, dual-, tri-, quad-, hexa-, octo-, dodeca-, deca-hexa and deca-octocopters), together with the wide variety of navigation options (e.g. altitude and position hold, waypoint flight) and camera mounts indicate that these platforms are here to stay for some time. Given the multitude of still camera types and the image quality they are currently capable of, endless combinations of low- and high-cost LAAP solutions are available. In addition, LAAP allows for the exploitation of new imaging techniques, as it is often only a matter of lifting the appropriate device (e.g. video cameras, thermal frame imagers, hyperspectral line sensors). Archaeologists were among the first to adopt this technology, as it provided them with a means to easily acquire essential data from a unique point of view, whether for simple illustration purposes of standing historic structures or to compute three-dimensional (3D) models and orthophotographs from excavation areas. However, even very cheap multi-copters models require certain skills to pilot them safely. Additionally, malfunction or overconfidence might lift these devices to altitudes where they can interfere with manned aircrafts. As such, the safe operation of these devices is still an issue, certainly when flying on locations which can be crowded (such as students on excavations or tourists walking around historic places). As the future of UAS regulation remains unclear, this talk presents an alternative approach to aerial imaging: the Fotokite. Developed at the ETH Zürich, the Fotokite is a tethered flying camera that is essentially a multi-copter connected to the ground with a taut tether to achieve controlled flight. Crucially, it relies solely on onboard IMU (Inertial Measurement Unit) measurements to fly, launches in seconds, and is classified as not a UAS (Unmanned Aerial System), e.g. in the latest FAA (Federal Aviation Administration) UAS proposal. As a result it may be used for imaging cultural heritage in a variety of environments and settings with minimal training by non-experienced pilots. Furthermore, it is subject to less extensive certification, regulation and import/export restrictions, making it a viable solution for use at a greater range of sites than traditional methods. Unlike a balloon or a kite it is not subject to particular weather conditions and, thanks to active stabilization, is capable of a variety of intelligent flight modes. Finally, it is compact and lightweight, making it easy to transport and deploy, and its lack of reliance on GNSS (Global Navigation Satellite System) makes it possible to use in urban, overbuilt areas. After outlining its operating principles, the talk will present some archaeological case studies in which the Fotokite was used, hereby assessing its capabilities compared to the conventional UAS’s on the market

Adaptive fast open-loop maneuvers for quadrocopters

We present a conceptually and computationally lightweight method for the design and iterative learning of fast maneuvers for quadrocopters. We use first-principles, reduced-order models and we do not require nor make an attempt to follow a specific state trajectory—only the initial and the final states of the vehicle are taken into account. We evaluate the adaptation scheme through experiments on quadrocopters in the ETH Flying Machine Arena that perform multi-flips and other high-performance maneuver

Bracing System Development for a CLT-Residential Building Under Seismic Loading. Comparison of Results From a Climate Performance and Life Cycle Point of View

Research on the performance of a structure built from cross-laminated timber (further referred to as CLT or X-LAM) panels under seismic loading with different types of stiffening systems was conducted in this thesis. To begin with, the research considered the behaviour of an existing structure constructed from CLT panels under seismic loading. Based on the quantitative results of the analysis, conclusions about the strength and geometrical imperfection of the original structure were outlined. As the load bearing capacity of the frame had been proved to be insufficient, three different stiffening options for it were considered next. Consequently, the essential part of the thesis was devoted to the study of the behaviour of the structure, with different stiffening systems that rely on using concrete, steel and thicker CLT-wall elements. Another important aspect of the research was to compare the above-mentioned results from the point of climate performance and life cycle. To this end, each stiffening option was evaluated in terms of carbon dioxide emissions, and the results were compared. Hence, the work also contributed to the field of identifying the most efficient types of stiffening system from the point of view of carbon-dioxide footprint. The structural calculation was performed according to EN 1998-1: Eurocode 8 (EC8) and EN 1991-1: Eurocode 1 (EC1). To carry out a life cycle analysis (LCA), the One Click LCA sustainability platform was used. The results of the research indicated that adopting massive cross-laminated (X-LAM) timber panels is a feasible solution for high-performing building constructions in earthquake-prone zones. In such cases, selecting the appropriate stiffening system requires careful consideration of its dependencies on the architectural concept and life cycle assessment factors. Furthermore, additional studies are necessary, particularly regarding the structural design of connections and the development of damper technologies

Editorial: Golgi Dynamics in Physiological and Pathological Conditions

publishedVersio

COG Complex Complexities : Detailed Characterization of a Complete Set of HEK293T Cells Lacking Individual COG Subunits

The Conserved Oligomeric Golgi complex is an evolutionarily conserved multisubunit tethering complex (MTC) that is crucial for intracellular membrane trafficking and Golgi homeostasis. The COG complex interacts with core vesicle docking and fusion machinery at the Golgi; however, its exact mechanism of action is still an enigma. Previous studies of COG complex were limited to the use of CDGII (Congenital disorders of glycosylation type II)-COG patient fibroblasts, siRNA mediated knockdowns, or protein relocalization approaches. In this study we have used the CRISPR approach to generate HEK293T knock-out (KO) cell lines missing individual COG subunits. These cell lines were characterized for glycosylation and trafficking defects, cell proliferation rates, stability of COG subunits, localization of Golgi markers, changes in Golgi structure, and N-glycan profiling. We found that all KO cell lines were uniformly deficient in cis/medial-Golgi glycosylation and each had nearly abolished binding of Cholera toxin. In addition, all cell lines showed defects in Golgi morphology, retrograde trafficking and sorting, sialylation and fucosylation, but severities varied according to the affected subunit. Lobe A and Cog6 subunit KOs displayed a more severely distorted Golgi structure, while Cog2, 3, 4, 5, and 7 knock outs had the most hypo glycosylated form of Lamp2. These results led us to conclude that every subunit is essential for COG complex function in Golgi trafficking, though to varying extents. We believe that this study and further analyses of these cells will help further elucidate the roles of individual COG subunits and bring a greater understanding to the class of MTCs as a whole

The Sec34/Sec35p complex, a Ypt1p effector required for retrograde intra-Golgi trafficking, interacts with Golgi SNAREs and COPI vesicle coat proteins

The Sec34/35 complex was identified as one of the evolutionarily conserved protein complexes that regulates a cis-Golgi step in intracellular vesicular transport. We have identified three new proteins that associate with Sec35p and Sec34p in yeast cytosol. Mutations in these Sec34/35 complex subunits result in defects in basic Golgi functions, including glycosylation of secretory proteins, protein sorting, and retention of Golgi resident proteins. Furthermore, the Sec34/35 complex interacts genetically and physically with the Rab protein Ypt1p, intra-Golgi SNARE molecules, as well as with Golgi vesicle coat complex COPI. We propose that the Sec34/35 protein complex acts as a tether that connects cis-Golgi membranes and COPI-coated, retrogradely targeted intra-Golgi vesicles

Interaction of the conserved oligomeric Golgi complex with t-SNARE Syntaxin5a/Sed5 enhances intra-Golgi SNARE complex stability

Tethering factors mediate initial interaction of transport vesicles with target membranes. Soluble N-ethylmaleimide–sensitive fusion protein attachment protein receptors (SNAREs) enable consequent docking and membrane fusion. We demonstrate that the vesicle tether conserved oligomeric Golgi (COG) complex colocalizes and coimmunoprecipitates with intra-Golgi SNARE molecules. In yeast cells, the COG complex preferentially interacts with the SNARE complexes containing yeast Golgi target (t)-SNARE Sed5p. In mammalian cells, hCog4p and hCog6p interact with Syntaxin5a, the mammalian homologue of Sed5p. Moreover, fluorescence resonance energy transfer reveals an in vivo interaction between Syntaxin5a and the COG complex. Knockdown of the mammalian COG complex decreases Golgi SNARE mobility, produces an accumulation of free Syntaxin5, and decreases the steady-state levels of the intra-Golgi SNARE complex. Finally, overexpression of the hCog4p N-terminal Syntaxin5a-binding domain destabilizes intra-Golgi SNARE complexes, disrupting the Golgi. These data suggest that the COG complex orchestrates vesicular trafficking similarly in yeast and mammalian cells by binding to the t-SNARE Syntaxin5a/Sed5p and enhancing the stability of intra-Golgi SNARE complexes

Sec35p, a Novel Peripheral Membrane Protein, Is Required for ER to Golgi Vesicle Docking

SEC35 was identified in a novel screen for temperature-sensitive mutants in the secretory pathway of the yeast Saccharomyces cerevisiae (Wuestehube et al., 1996. Genetics. 142:393–406). At the restrictive temperature, the sec35-1 strain exhibits a transport block between the ER and the Golgi apparatus and accumulates numerous vesicles. SEC35 encodes a novel cytosolic protein of 32 kD, peripherally associated with membranes. The temperature-sensitive phenotype of sec35-1 is efficiently suppressed by YPT1, which encodes the rab-like GTPase required early in the secretory pathway, or by SLY1-20, which encodes a dominant form of the ER to Golgi target -SNARE–associated protein Sly1p. Weaker suppression is evident upon overexpression of genes encoding the vesicle-SNAREs SEC22, BET1, or YKT6. The cold-sensitive lethality that results from deleting SEC35 is suppressed by YPT1 or SLY1-20. These genetic relationships suggest that Sec35p acts upstream of, or in conjunction with, Ypt1p and Sly1p as was previously found for Uso1p. Using a cell-free assay that measures distinct steps in vesicle transport from the ER to the Golgi, we find Sec35p is required for a vesicle docking stage catalyzed by Uso1p. These genetic and biochemical results suggest Sec35p acts with Uso1p to dock ER-derived vesicles to the Golgi complex

Novel Role for the Golgi Membrane Protein TMEM165 in Control of Migration and Invasion for Breast Carcinoma

The TMEM165 gene encodes for a multiple pass membrane protein localized in the Golgi that has been linked to congenital disorders of glycosylation. The TMEM165 protein is a putative ion transporter that regulates H+/Ca++/Mn++ homeostasis and pH in the Golgi. Previously, we identified TMEM165 as a potential biomarker for breast carcinoma in a glycoproteomic study using late stage invasive ductal carcinoma tissues with patient-matched adjacent normal tissues. The TMEM165 protein was not detected in non-malignant matched breast tissues and was detected in invasive ductal breast carcinoma tissues by mass spectrometry. Our hypothesis is that the TMEM165 protein confers a growth advantage to breast cancer. In this preliminary study we have investigated the expression of TMEM165 in earlier stage invasive ductal carcinoma and ductal carcinoma in situ cases. We created a CRISPR/Cas9 knockout of TMEM165 in the human invasive breast cancer cell line MDAMB231. Our results indicate that removal of TMEM165 in these cells results in a significant reduction of cell migration, tumor growth, and tumor vascularization in vivo. Furthermore, we find that TMEM165 expression alters the glycosylation of breast cancer cells and these changes promote the invasion and growth of breast cancer by altering the expression levels of key glycoproteins involved in regulation of the epithelial to mesenchymal transition such as E-cadherin. These studies illustrate new potential functions for this Golgi membrane protein in the control of breast cancer growth and invasion