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Individual atomic defects in 2D materials impact their macroscopic functionality. Correlating the interplay is challenging, however, intelligent hyperspectral scanning tunneling spectroscopy (STS) mapping provides a feasible solution to this technically difficult and time consuming problem. Here, dense spectroscopic volume is collected autonomously via Gaussian process regression, where convolutional neural networks are used in tandem for spectral identification. Acquired data enable defect segmentation, and a workflow is provided for machine-driven decision making during experimentation with capability for user customization. We provide a means towards autonomous experimentation for the benefit of both enhanced reproducibility and user-accessibility. Hyperspectral investigations on WS2 sulfur vacancy sites are explored, which is combined with local density of states confirmation on the Au{111} herringbone reconstruction. Chalcogen vacancies, pristine WS2, Au face-centered cubic, and Au hexagonal close-packed regions are examined and detected by machine learning methods to demonstrate the potential of artificial intelligence for hyperspectral STS mapping.

Public management research has paid increasing attention to the public value paradigm. Despite the number of studies on the topic, we do not yet have a comprehensive empirical understanding of what happens when the public value paradigm is translated into performance measurement regimes and models. A major issue here is how to integrate public value measurement across networks of business, civil society, and government within which public policies and services are implemented these days. By looking for implications for public management, this chapter aims to offer a set of preliminary answers to the question of how governments themselves should shape policymaking, performance measurement, and reporting in order to integrate the contribution of civil society and private business to public value creation. Presented in this chapter are the results from a case study of a regional government in Italy experiencing boundary- crossing public value measurement and reporting. The goal of the research was to collect information about how measurement efforts at the local level reflect public value creation in a networked setting, about the process that was used for community engagement, and about the extent to which the process to develop public value measurement and reporting is relevant for public and private leaders. As a conclusion, some implications for public management and governance are emphasized.

Background: Marine Synechococcus owe their specific vivid color (ranging from blue-green to orange) to their large extrinsic antenna complexes called phycobilisomes, comprising a central allophycocyanin core and rods of variable phycobiliprotein composition. Three major pigment types can be defined depending on the major phycobiliprotein found in the rods (phycocyanin, phycoerythrin I or phycoerythrin II). Among strains containing both phycoerythrins I and II, four subtypes can be distinguished based on the ratio of the two chromophores bound to these phycobiliproteins. Genomes of eleven marine Synechococcus strains recently became available with one to four strains per pigment type or subtype, allowing an unprecedented comparative genomics study of genes involved in phycobilisome metabolism. Results: By carefully comparing the Synechococcus genomes, we have retrieved candidate genes potentially required for the synthesis of phycobiliproteins in each pigment type. This includes linker polypeptides, phycobilin lyases and a number of novel genes of uncharacterized function. Interestingly, strains belonging to a given pigment type have similar phycobilisome gene complements and organization, independent of the core genome phylogeny (as assessed using concatenated ribosomal proteins). While phylogenetic trees based on concatenated allophycocyanin protein sequences are congruent with the latter, those based on phycocyanin and phycoerythrin notably differ and match the Synechococcus pigment types. Conclusion: We conclude that the phycobilisome core has likely evolved together with the core genome, while rods must have evolved independently, possibly by lateral transfer of phycobilisome rod genes or gene clusters between Synechococcus strains, either via viruses or by natural transformation, allowing rapid adaptation to a variety of light niches. © 2007 Six et al.; licensee BioMed Central Ltd.

Let C be a differential graded chain coalgebra, &UOmega; C the reduced cobar construction on C and C-V the dual algebra. We prove that for a large class of coalgebras C there is a natural isomorphism of Gerstenhaber algebras between the Hochschild cohomologies, HH*(C-V, C-V) and HH*(&UOmega; C; &UOmega; C). This result yields to a Hodge decomposition of the loop space homology of a closed oriented manifold, when the field of coefficients is of characteristic zero. © 2004 Elsevier B.V. All rights reserved.

We present a method for the detection of charged particles. emitted following beta decay, that allows to reduce the background due to beta radiation and thus to facilitate separation of the delayed-particle events, The isotopes of interest are implanted into a highly segmented double-sided silicon strip detector, resulting in excellent precision on the overall normalisation. The characteristics of the detector and the particle signatures are discussed, This method can be applied to a variety of systems close to the proton and neutron driplines. it region which the recent availability of post-accelerated radioactive beams has opened up for study. To demonstrate this, we measured the branching ratio of He-6 beta decay into the alpha + d two-body continuum of Li-6. We obtained it Value of(1.7 +/- 04) x 10(-6) for energies x + d above 525 keV. (c) 2005 Elsevier B.V. All rights reserved.

Let M be a closed orientable manifold of dimension d and l*(M) be the usual cochain algebra on M with coefficients in a field k. The Hochschild cohomology of M, HH* (l* (M); l* (M)) is a graded commutative and associative algebra. The augmentation map E : l* (M) -> k induces a morphism of algebras I : HH* (l* (M); l* (M)) -> HH* (l* (M); k). In this paper we produce a chain model for the morphism I. We show that the kernel of I is a nilpotent ideal and that the image of I is contained in the center of HH*(l*(M); k), which is in general quite small. The algebra HH*(l*(M); l*(M)) is expected to be isomorphic to the loop homology constructed by Chas and Sullivan. Thus our results would be translated in terms of string homology.

Let M be a simply-connected closed oriented N-dimensional manifold. We prove that for any field of coefficients lk there exists a natural homomorphism of commutative graded algebras Gamma : H-*(Omega aut(1)M) --> H*(M-S1) where H-*(M-S1) = H*+N(M-S1) is the loop algebra defined by Chas and Sullivan. As usual aut(1)X denotes the monoid of self-equivalences homotopic to the identity, and OmegaX the space of based loops. When lk is of characteristic zero, Gamma yields isomorphisms H-(1)(n+N) (M-S1) congruent to (pi(n)(Omegaaut(1)M) x lk)(boolean OR) where +(infinity)(l=1) H-(l)(n)(M-S1) denotes the Hodge decomposition on H*(M-S1).

If A is a graded connected algebra then we define a new invariant, polydepth A, which is finite if Ext*(A) (M, A) not equal 0 for some A-module M of at most polynomial growth. THEOREM 1: If f : X --> Y is a continuous map of finite category, and if the orbits of H*(OmegaY) acting in the homology of the homotopy fibre grow at most polynomially, then H*(OmegaY) has finite polydepth. THEOREM 5: If L is a graded Lie algebra and polydepth UL is finite then either L is solvable and UL grows at most polynomially or else for some integer d and all r, Sigma(i=k+1)(k+d) dim L-i greater than or equal to V, k greater than or equal to some k(r). (C) 2003 Elsevier SAS.

In this paper we make explicit the relationship between the category of a connected CW complex and the category of its skeleta. In particular we prove that if Y is a connected non-contractible CW complex, then cat Y-k less than or equal to cat Y for each k-skeleton Y-k. On the other hand, we prove that cat(0)(Y) = lim(k-->infinity) cat(0)(Y-k), where cat(0) denotes the rational category of the space. (C) 2001 Elsevier Science B.V. All rights reserved.

In a fibration OmegaF (Omegaj)under right arrow OmegaX (Omega pi )under right arrow OmegaB we show that finiteness conditions on F force the homology Serre spectral sequence with F-p-coefficients to collapse at some finite term. This in particular implies that as graded vector spaces, H-*(OmegaX) is "almost" isomorphic to H-*(OmegaB) circle times H-*(OmegaF). One consequence is the conclusion that X is elliptic if and only if B and F are.

We compute the loop space homology of the space F(M,k) of configurations of k points in a compact simply connected manifold M. We prove in particular that, if H* (M, Q) is not generated by one generator, then the rational homology of OMEGAF (M, k) contains a tensor algebra for k greater-than-or-equal-to 2.

Let A be a graded algebra of finite type over a field K. Anick has conjectured that if A has finite global dimension then A is linearly isomorphic to a graded polynomial algebra. When the ground field has odd characteristic we give a counterexample which is a cocommutative graded Hopf algebra. We also show that in this context the conjecture is true in characteristic zero or two and is almost true in odd characteristic. We propose a companion conjecture for Ext A(K, K) and prove it when A = UL, some graded Lie algebra L. (C) 1994 Academic Press, Inc.

We compare three natural subvectorspaces of the cohomology of a simply connected pointed space. These spaces are related to, respectively, the ''last cells'' of the space, the ''dual Gottlieb groups'' and the ''evaluation map'' defined by the Spivak construction.

Let k be a field of positive characteristic and X be a simply connected space of the homotopy type of a finite type CW complex. The Postnikov fibre X([n]) of X is defined as the homotopy fibre of the n-equivalence fn: X --> X(n) coming from the Postnikov tower {X(n)} of X. We prove that if the Lusternik-Schnirelmann category of X is finite, then H*(X[n];k) contains a free module on a subalgebra K of H* (OMEGAX(n);k) such that H* (OMEGAX(n);k) is a finite-dimensional free K-module.

Let f : Y --> X be a continuous map between connected CW complexes. The homology H* (F) of the homotopy fibre is then a module over the loop space homology H* (OMEGAX). THEOREM: If H*(F; R) and H*(OMEGAX; R) are R-free (R a principal ideal domain) then for some H*(OMEGAX; R)-projective module P=P(greater-than-or-equal-to 0) and for some m less-than-or-equal-to cat f: Ext(H* (OMEGAX)m(H* (F); P) not-equal 0. Some applications are also given.

Kac has introduced the notion of (polynomial) growth for a graded Lie algebra. Here we consider Lie algebras L that occur as ideals either in the rational homotopy Lie algebra of a simply connected CW complex of finite type and finite category or as ideals in the homotopy Lie algebra of a local noetherian ring. Theorem. If these ideals have (finite) polynomial growth, then they are finite dimensional.

An elliptic Hopf algebra is a connected graded cocommutative Hopf algebra that is finitely generated and nilpotent. If (A,m,k) is a local noetherian ring then Ext(A)(k; k) is elliptic if and only A is a complete intersection. Similarly, special conditions are imposed on a simply connected topological space X if H*(OMEGA-X; k) is elliptic. Elliptic Hopf algebras G have finite depth and we show that they are characterized among Hopf algebras of finite depth by any of the following three properties: (i) SIGMA-i less-than-or-equal-to n dim G(i) grows at most polynomially in n; (ii) G is left noetherian; (iii) G is nilpotent.

Let X be a 1-connected space such that each H(j)(X;Z) is finitely generated. In this paper we prove that if the reduced homology of X with coefficients in a field is nonzero, then the Lusternik-Schnirelmann category of the free loop space is infinite.