877 research outputs found
Development of a Patient Behaviour Model for an Adaptive Medical Robot
No full textThis article focuses on the development and evaluation of a patient behaviour model, which is to be used to quantify the patient’s contribution to the generation of the movements performed during robot-assisted lower limb mobilization. This model allows adaptation of the robot’s behaviour based on the patient’s capabilities in order to guarantee a therapy progression. The work provides a strategy based both on first principles and data-driven approaches, to ensure the trustworthiness of the model (due to knowledge of the underlying mechanics) and suitability of the model for limited amounts of data. Our best performing model, which includes a cooperation between those two strategies, is able to predict the required torques for the mobilization of a completely passive subject during different therapy configurations. The model only uses data available from the robotic system without exploiting additional sensors. Validation is conducted with real human data from a total of 10 healthy subjects
Five-Coordinate Rearrangements of Metallacyclobutane Intermediates during Ring-Opening Metathesis Polymerization of 2,3-Dicarboalkoxynorbornenes by Molybdenum and Tungsten Monoalkoxide Pyrrolide Initiators
No full textAddition of rac-DCENBE (2,3-dicarboethoxynorbornene) or rac-DCBNBE (2,3-dicarbo-tert-butoxynorbornene) to Mo(NAd)(CHCMe[subscript 2]Ph)(Pyr)(OHMT) (1a) (Ad = 1-adamantyl, OHMT = 2,6-dimesitylphenoxide, Pyr– = NC[subscript 4]H[subscript 4]–) led to the formation of polymers that have a cis,syndiotactic,alt structure analogous to the structure observed for the polymer obtained from rac-DCMNBE (2,3-dicarbomethoxynorbornene). The PDI of cis,syndio,alt-poly(DCBNBE) is low and decreases as the polymer length increases, and there is a linear relationship between the number of equivalents of monomer employed and the molecular weight of the polymers measured in THF versus polystyrene standards. In contrast, polymerization of (+)-DCMNBE by 1a at 25, 0, −25, and −40 °C yields a polymer that contains ~25% trans,isotactic dyads and 75% cis,syndiotactic dyads. A similar polymerization by Mo(NAd)(CHCMe[subscript 2]Ph)(Pyr)(OHIPT) (1b) (OHIPT = 2,6-(2,4,6-i-Pr[subscript 3])[subscript 2]C[subscript 6]H[subscript 3]) gives a polymer that contains cis,syndiotactic and trans,isotactic dyads in a ratio of ~8:92, respectively. This is the first report of synthesis of a norbornene polymer that has primarily a trans,isotactic structure. Addition of 100 equiv of (+)-DCMNBE, (−)-DCENBE, or (−)-DCBNBE to a toluene solution of W(O)(CH-t-Bu)(2,5-Me[subscript 2]NC[subscript 4]H[subscript 2])(OHMT)(PMe[subscript 2]Ph) (5) led to formation of ~99% cis,syndiotactic polymer. Cis,syndiotactic dyads arise through a mechanism that consists of a syn approach of the monomer to a syn alkylidene isomer followed by inversion of configuration at the metal center as a consequence of an exchange of aryloxide and pyrrolide ligands. The mechanism for formation of trans,isotactic dyads is one in which the monomer approaches in an anti fashion to the syn isomer followed by a “turnstile” rotation in the five-coordinate intermediate metallacyclobutane that allows the metallacylic ring to open productively with retention of configuration at the metal center. The metallacyclobutane intermediate that gives rise to trans,isotactic dyads in the copolymer could be regarded as a relatively high energy species with a “nonideal” structure compared to a trigonal bipyramidal or a square pyramidal structure.United States. Dept. of Energy (DE-FG02-86ER13564
Pseudosinella octopunctata BORNER 1901
No full text<i>Pseudosinella octopunctata</i> BÖRNER 1901 <p>M a t e r i a l: 6 Expl. Molchos, 14 Expl. Vai Palm Beach, 1 Expl. Kritsa Katharo Plateau/1.</p> <p>Eine typische Art in trockenen, warmen Habitaten (FJELLBERG 2007). Kosmopolit.</p>Published as part of <i>H. - J & Burkhardt, U., 2012, Interessante Collembolennachweise aus Ostkreta (Hexapoda, Collembola), pp. 1669-1676 in Linzer biologische Beiträge 44 (2)</i> on page 1672, DOI: <a href="http://zenodo.org/record/10106991">10.5281/zenodo.10106991</a>
Interindividual variance of glucose-6 phosphatase (G-8-Pse) expression in renal cell cancer
No full textInterindividual variance of glucose-6 phosphatase (G-8-Pse) expression in renal cell cancer
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Brookhaven National Laboratory Report BNL-6744
No full textInnes, Zemen, Frenkel, Borner and Wright (1962) described an outbreak of encephalitozoönosis of the central nervous system in mice, a summary of which is given below for an understanding of why this appendix may be of interest. When the paper was presented for publication, the editors of the journal decided to omit the history of our mouse colony. In our opinion, to understand (a) how this infection may have arisen and (b) may have spread, and still exist in some colonies, it is of prime importance to know the history of this strain of mice used by us (and others). It also has lessons on the establishment and maintenance of so-called "disease-free" or "specific pathogen-free"* colonies of laboratory animals in general. Information on the history of the mice has been culled from Col. H. Yager, VC, Director of the Division of Veterinary Medicine, Walter Reed Army Institute of Medical Research, Washington, D. C., and from Drs, Clara Lynch and John B. Nelson, Rockefeller Institute, New York
Synthesis, Structure and Magnetic Properties of Some Copper(II) Complexes Supported by Pendant Calix[4]arene Ligands
No full textThe synthesis and characterization of three new calix[4]arene ligands bearing two pendant acylhydrazone arms and some of their Cu2+ complexes, namely [Cu(L1-2H)(MeOH)] (3), [Cu(L1’-H)(Cl)(2-hydroxy-1-naphthaldehyde)] (4), [Cu2(L2-2H)2] (5) and [Cu4(L3-2H)2(OH)2(ClO4)2] (6) are described. The ligands are obtained by simple imine condensation reactions between calix[4]arene-1,3-bis-acyl-hydrazides and the corresponding carbaldehydes. The Cu2+ ions are always situated in 5-membered chelate rings, either in a deprotonated −O−CR=N−N=CHR (enolate) or a neutral O=CR−NH−N=CHR (keto) form. In 3 and 4 a 5-membered chelate ring is formed through interaction of the Cu2+ ion with the naphtholato group. Additional MeOH, chlorido or naphthaldehyde ligands complete the planar (3) or square pyramidal (4) coordination spheres. The thiophenes in 5 do not interact with the Cu2+ ions and dimerization of [CuL] entities occurs to produce centrosymmetric 2 : 2 complexes with four-coordinated Cu2+ ions. In 6, two dinuclear [Cu2(L3-2H)(OH)] subunits are connected by μ1,3-bridging ClO4− ions. The magnetic properties of polycrystalline samples of 5 and 6 were studied by variable temperature magnetic susceptibility measurements. The χ′′(T) vs T plots indicate antiferromagnetic exchange interactions. The exchange interactions in 6 (J=−4.8 cm−1) were found to be stronger than in 5 (J=−0.54 cm−1). This is also supported by broken symmetry DFT calculations
AP-4-mediated axonal transport controls endocannabinoid production in neurons
No full textDavies et al. identify a putative mechanism underlying the childhood neurological disorder AP-4 deficiency syndrome. In the absence of AP-4, an enzyme that makes 2-AG is not transported to the axon, leading to axonal growth defects, which can be rescued by inhibition of 2-AG breakdown. The adaptor protein complex AP-4 mediates anterograde axonal transport and is essential for axon health. AP-4-deficient patients suffer from a severe neurodevelopmental and neurodegenerative disorder. Here we identify DAGLB (diacylglycerol lipase-beta), a key enzyme for generation of the endocannabinoid 2-AG (2-arachidonoylglycerol), as a cargo of AP-4 vesicles. During normal development, DAGLB is targeted to the axon, where 2-AG signalling drives axonal growth. We show that DAGLB accumulates at the trans-Golgi network of AP-4-deficient cells, that axonal DAGLB levels are reduced in neurons from a patient with AP-4 deficiency, and that 2-AG levels are reduced in the brains of AP-4 knockout mice. Importantly, we demonstrate that neurite growth defects of AP-4-deficient neurons are rescued by inhibition of MGLL (monoacylglycerol lipase), the enzyme responsible for 2-AG hydrolysis. Our study supports a new model for AP-4 deficiency syndrome in which axon growth defects arise through spatial dysregulation of endocannabinoid signalling.Special thanks to the MPIB Imaging Facility for outstanding technical support, in particular to Giovanni Cardone for his advice and assistance with the implementation of image analysis pipelines, as well as feedback on the manuscript, and to Martin Spitaler for his expert technical advice for imaging experiments
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