Deformations of calibrated subbundles of Euclidean spaces via twisting by special sections

We extend the "bundle constructions" of calibrated submanifolds, due to Harvey--Lawson in the special Lagrangian case, and to Ionel--Karigiannis--Min-Oo in the cases of exceptional calibrations, by "twisting" the bundles by a special (harmonic, holomorphic, parallel) section of a complementary bundle. The existence of such deformations shows that the moduli space of calibrated deformations of these "calibrated subbundles" includes deformations which destroy the linear structure of the fibre.Comment: 16 pages, no figures. Version 2: Only minor cosmetic and typographical revisions. To appear in "Annals of Global Analysis and Geometry.

Quilted Floer Cohomology

We generalize Lagrangian Floer cohomology to sequences of Lagrangian correspondences. For sequences related by the geometric composition of Lagrangian correspondences we establish an isomorphism of the Floer cohomologies. We give applications to calculations of Floer cohomology, displaceability of Lagrangian correspondences, and transfer of displaceability under geometric composition.Comment: minor corrections and updated reference

Rational Moral Ignorance

Philosophy and Phenomenological Research, EarlyView

Electrostatic Patch Effect in Cylindrical Geometry. I. Potential and Energy between Slightly Non-Coaxial Cylinders

We study the effect of any uneven voltage distribution on two close cylindrical conductors with parallel axes that are slightly shifted in the radial and by any length in the axial direction. The investigation is especially motivated by certain precision measurements, such as the Satellite Test of the Equivalence Principle (STEP). By energy conservation, the force can be found as the energy gradient in the vector of the shift, which requires determining potential distribution and energy in the gap. The boundary value problem for the potential is solved, and energy is thus found to the second order in the small transverse shift, and to lowest order in the gap to cylinder radius ratio. The energy consists of three parts: the usual capacitor part due to the uniform potential difference, the one coming from the interaction between the voltage patches and the uniform voltage difference, and the energy of patch interaction, entirely independent of the uniform voltage. Patch effect forces and torques in the cylindrical configuration are derived and analyzed in the next two parts of this work.Comment: 26 pages, 1 Figure. Submitted to Classical and Quantum Gravit

Fivebranes and 4-manifolds

We describe rules for building 2d theories labeled by 4-manifolds. Using the proposed dictionary between building blocks of 4-manifolds and 2d N=(0,2) theories, we obtain a number of results, which include new 3d N=2 theories T[M_3] associated with rational homology spheres and new results for Vafa-Witten partition functions on 4-manifolds. In particular, we point out that the gluing measure for the latter is precisely the superconformal index of 2d (0,2) vector multiplet and relate the basic building blocks with coset branching functions. We also offer a new look at the fusion of defect lines / walls, and a physical interpretation of the 4d and 3d Kirby calculus as dualities of 2d N=(0,2) theories and 3d N=2 theories, respectivelyComment: 81 pages, 18 figures. v2: misprints corrected, clarifications and references added. v3: additions and corrections about lens space theory, 4-manifold gluing, smooth structure

Feasibility study of the solar scientific instruments for Spacelab/Orbiter

The feasibility and economics of mounting and operating a set of solar scientific instruments in the backup Skylab Apollo Telescope Mount (ATM) hardware was evaluated. The instruments used as the study test payload and integrated into the ATM were: the Solar EUV Telescope/Spectrometer; the Solar Active Region Observing Telescope; and the Lyman Alpha White Light Coronagraph. The backup ATM hardware consists of a central cruciform structure, called the "SPAR', a "Sun End Canister' and a "Multiple Docking Adapter End Canister'. Basically, the ATM hardware and software provides a structural interface for the instruments; a closely controlled thermal environment; and a very accurate attitude and pointing control capability. The hardware is an identical set to the hardware that flow on Skylab

Asymptotically cylindrical 7-manifolds of holonomy G_2 with applications to compact irreducible G_2-manifolds

We construct examples of exponentially asymptotically cylindrical Riemannian 7-manifolds with holonomy group equal to G_2. To our knowledge, these are the first such examples. We also obtain exponentially asymptotically cylindrical coassociative calibrated submanifolds. Finally, we apply our results to show that one of the compact G_2-manifolds constructed by Joyce by desingularisation of a flat orbifold T^7/\Gamma can be deformed to one of the compact G_2-manifolds obtainable as a generalized connected sum of two exponentially asymptotically cylindrical SU(3)-manifolds via the method given by the first author (math.DG/0012189).Comment: 36 pages; v2: corrected trivial typos; v3: some arguments corrected and improved; v4: a number of improvements on presentation, paritularly in sections 4 and 6, including an added picture

Mobile radio interferometric geodetic systems

Operation of the Astronomical Radio Interferometric Earth Surveying (ARIES) in a proof of concept mode is discussed. Accuracy demonstrations over a short baseline, a 180 km baseline, and a 380 km baseline are documented. Use of ARIES in the Sea Slope Experiment of the National Geodetic Survey to study the apparent differences between oceanographic and geodetic leveling determinations of the sea surface along the Pacific Coast is described. Intergration of the NAVSTAR Global Positioning System and a concept called SERIES (Satellite Emission Radio Interferometric Earth Surveying) is briefly reviewed

PIB is a non-specific imaging marker of amyloid-beta (Aβ) peptide-related cerebral amyloidosis

The in vivo imaging probe [11C]-PIB (Pittsburgh Compound B, N-methyl[11C]2-(4′-methylaminophenyl-6-hydroxybenzathiazole) is under evaluation as a key imaging tool in Alzheimer's disease (AD) and to date has been assumed to bind with high affinity and specificity to the amyloid structures associated with classical plaques (CPs), one of the pathological hallmarks of the disease. However, no studies have systematically investigated PIB binding to human neuropathological brain specimens at the tracer concentrations achieved during in vivo imaging scans. Using a combination of autoradiography and histochemical techniques, we demonstrate that PIB, in addition to binding CPs clearly delineates diffuse plaques and cerebrovascular amyloid angiopathy (CAA). The interaction of PIB with CAA was not fully displaceable and this may be linked to the apolipoprotein E-ε4 allele. PIB was also found to label neurofibrillary tangles, although the overall intensity of this binding was markedly lower than that associated with the amyloid-beta (Aβ) pathology. The data provide a molecular explanation for PIB's limited specificity in diagnosing and monitoring disease progression in AD and instead indicate that the ligand is primarily a non-specific marker of Aβ-peptide related cerebral amyloidosi

Elevated alpha-synuclein caused by SNCA gene triplication impairs neuronal differentiation and maturation in Parkinson's patient-derived induced pluripotent stem cells

We have assessed the impact of α-synuclein overexpression on the differentiation potential and phenotypic signatures of two neural-committed induced pluripotent stem cell lines derived from a Parkinson´s disease patient with a triplication of the human SNCA genomic locus. In parallel, comparative studies were performed on two control lines derived from healthy individuals and lines generated from the patient iPS-derived neuroprogenitor lines infected with a lentivirus incorporating a small hairpin RNA to knock down the SNCA mRNA. The SNCA triplication lines exhibited a reduced capacity to differentiate into dopaminergic or GABAergic neurons and decreased neurite outgrowth and lower neuronal activity compared with control cultures. This delayed maturation phenotype was confirmed by gene expression profiling, which revealed a significant reduction in mRNA for genes implicated in neuronal differentiation such as delta-like homolog 1 (DLK1), gamma-aminobutyric acid type B receptor subunit 2 (GABABR2), nuclear receptor related 1 protein (NURR1), G-protein-regulated inward-rectifier potassium channel 2 (GIRK-2) and tyrosine hydroxylase (TH). The differentiated patient cells also demonstrated increased autophagic flux when stressed with chloroquine. We conclude that a two-fold overexpression of α-synuclein caused by a triplication of the SNCA gene is sufficient to impair the differentiation of neuronal progenitor cells, a finding with implications for adult neurogenesis and Parkinson´s disease progression, particularly in the context of bioenergetic dysfunction.Fil: Oliveira, L. M. A.. Max-Planck-Institut für biophysikalische Chemie; AlemaniaFil: Falomir Lockhart, Lisandro Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; Argentina. Max-Planck-Institut für biophysikalische Chemie; AlemaniaFil: Botelho, M. G.. Max-Planck-Institut für biophysikalische Chemie; Alemania. Universidade Federal do Rio de Janeiro; BrasilFil: Lin, K. H.. Max-Planck-Institut für biophysikalische Chemie; AlemaniaFil: Wales, P.. Universität Göttingen; AlemaniaFil: Koch, J. C.. Universität Göttingen; AlemaniaFil: Gerhardt, Elizabeth. Universität Göttingen; AlemaniaFil: Taschenberger, H.. Max-Planck-Institut für biophysikalische Chemie; AlemaniaFil: Outeiro, T. F.. Universität Göttingen; AlemaniaFil: Lingor, P.. Universität Göttingen; AlemaniaFil: Schüele, B.. The Parkinson’s Institute; Estados UnidosFil: Arndt Jovin, D. J.. Max-Planck-Institut für biophysikalische Chemie; AlemaniaFil: Jovin, T. M.. Max-Planck-Institut für biophysikalische Chemie; Alemani