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  1. null (Ed.)
    This paper presents a novel strategy for the autonomous deployment of Micro Aerial Vehicle scouts through constricted aperture-like ingress points, by narrowly fitting and launching them with a high-precision Mobile Manipulation robot. A significant problem during exploration and reconnaissance into highly unstructured environments, such as indoor collapsed ones, is the encountering of impassable areas due to their constricted and rigid nature. We propose that a heterogeneous robotic system-of-systems armed with manipulation capabilities while also ferrying a fleet of micro-sized aerial agents, can deploy the latter through constricted apertures that marginally fit them in size, thus allowing them to act as scouts and resume the reconnaissance mission. This work's contribution is twofold: first, it proposes active-vision based aperture detection to locate candidate ingress points and a hierarchical search-based aperture profile analysis to position a MAV's body through them, and secondly it presents and experimentally demonstrates the novelty of a system-of-systems approach which leverages mobile manipulation to deploy other robots which are otherwise incapable of entering through extremely narrow openings. 
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  2. null (Ed.)
    This paper addresses the problem of autonomously deploying an unmanned aerial vehicle in non-trivial settings, by leveraging a manipulator arm mounted on a ground robot, acting as a versatile mobile launch platform. As real-world deployment scenarios for micro aerial vehicles such as searchand- rescue operations often entail exploration and navigation of challenging environments including uneven terrain, cluttered spaces, or even constrained openings and passageways, an often arising problem is that of ensuring a safe take-off location, or safely fitting through narrow openings while in flight. By facilitating launching from the manipulator end-effector, a 6- DoF controllable take-off pose within the arm workspace can be achieved, which allows to properly position and orient the aerial vehicle to initialize the autonomous flight portion of a mission. To accomplish this, we propose a sampling-based planner that respects a) the kinematic constraints of the ground robot / manipulator / aerial robot combination, b) the geometry of the environment as autonomously mapped by the ground robots perception systems, and c) accounts for the aerial robot expected dynamic motion during takeoff. The goal of the proposed planner is to ensure autonomous collision-free initialization of an aerial robotic exploration mission, even within a cluttered constrained environment. At the same time, the ground robot with the mounted manipulator can be used to appropriately position the take-off workspace into areas of interest, effectively acting as a carrier launch platform. We experimentally demonstrate this novel robotic capability through a sequence of experiments that encompass a micro aerial vehicle platform carried and launched from a 6-DoF manipulator arm mounted on a four-wheel robot base. 
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  3. We report a diaryldiselenide catalyst for cross-dehydrogenative nucleophilic functionalization of hydrophosphoryl compounds. The proposed organocatalytic cycle closely resembles the mechanism of the Atherton–Todd reaction, with the catalyst serving as a recyclable analogue of the halogenating agent employed in the named reaction. Phosphorus and selenium NMR studies reveal the existence of a P–Se bond intermediate, and structural analyses indicate a stereospecific reaction. 
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  4. Amide bonds are ubiquitous in peptides, proteins, pharmaceuticals, and polymers. The formation of amide bonds is a straightforward process: amide bonds can be synthesized with relative ease because of the availability of efficient coupling agents. However, there is a substantive need for methods that do not require excess reagents. A catalyst that condenses amino acids could have an important impact by reducing the significant waste generated during peptide synthesis. We describe the rational design of a biomimetic catalyst that can efficiently couple amino acids featuring standard protecting groups. The catalyst design combines lessons learned from enzymes, peptide biosynthesis, and organocatalysts. Under optimized conditions, 5 mol % catalyst efficiently couples Fmoc amino acids without notable racemization. Importantly, we demonstrate that the catalyst is functional for the synthesis of oligopeptides on solid phase. This result is significant because it illustrates the potential of the catalyst to function on a substrate with a multitude of amide bonds, which may be expected to inhibit a hydrogen-bonding catalyst. 
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