Important Building Block (important + building_block)

Distribution by Scientific Domains


Selected Abstracts


An Experimental Investigation of Approaches to Audit Decision Making: An Evaluation Using Systems-Mediated Mental Models,

CONTEMPORARY ACCOUNTING RESEARCH, Issue 2 2005
AMY K. CHOY
Abstract The objective of this research is to articulate a decision-making foundation for the systems audit approach. Under this audit approach, the auditor first gains an understanding of the auditee's economic environment, strategy, and business processes and then forms expectations about its performance and financial reporting. Proponents of this audit approach argue that decision making is enhanced because the knowledge of the system allows the auditor to focus on the most important risks. However, there has not been an explicit framework to explain how systems knowledge can enhance decision making. To provide such a framework, we combine mental model theory with general systems theory to produce a hypothesis we refer to as a systems-mediated mental model hypothesis. We test this hypothesis using experimental economics methods. We find that (1) subjects make systematic errors under the setting without an organizing framework provided by the systems information, and (2) the presence of an organizing framework results in lower reporting errors. Importantly, the organizing framework significantly enhances decision making in the settings where the environment changed. Establishing a decision-making foundation for systems audits can provide an important building block that, in part, can contribute to the development of a more effective and efficient audit technology - an important objective now when audits are facing a credibility crisis. [source]


Vertically Aligned Single-Walled Carbon Nanotubes by Chemical Assembly , Methodology, Properties, and Applications

ADVANCED MATERIALS, Issue 13 2010
Peng Diao
Abstract Single-walled carbon nanotubes (SWNTs), as one of the most promising one-dimension nanomaterials due to its unique structure, peculiar chemical, mechanical, thermal, and electronic properties, have long been considered as an important building block to construct ordered alignments. Vertically aligned SWNTs (v-SWNTs) have been successfully prepared by using direct growth and chemical assembly strategies. In this review, we focus explicitly on the v-SWNTs fabricated via chemical assembly strategy. We provide the readers with a full and systematic summary covering the advances in all aspects of this area, including various approaches for the preparation of v-SWNTs using chemical assembly techniques, characterization, assembly kinetics, and electrochemical properties of v-SWNTs. We also review the applications of v-SWNTs in electrochemical and bioelectrochemical sensors, photoelectric conversion, and scanning probe microscopy. [source]


Updates on stem cells and their applications in regenerative medicine

JOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 4 2008
Stefan Bajada
Abstract Stem cells have the capacity for self-renewal and capability of differentiation to various cell lineages. Thus, they represent an important building block for regenerative medicine and tissue engineering. These cells can be broadly classified into embryonic stem cells (ESCs) and non-embryonic or adult stem cells. ESCs have great potential but their use is still limited by several ethical and scientific considerations. The use of bone marrow-, umbilical cord-, adipose tissue-, skin- and amniotic fluid-derived mesenchymal stem cells might be an adequate alternative for translational practice. In particular, bone marrow-derived stem cells have been used successfully in the clinic for bone, cartilage, spinal cord, cardiac and bladder regeneration. Several preclinical experimental studies are under way for the application of stem cells in other conditions where current treatment options are inadequate. Stem cells can be used to improve healthcare by either augmenting the body's own regenerative potential or developing new therapies. This review is not meant to be exhaustive but gives a brief outlook on the past, present and the future of stem cell-based therapies in clinical practice. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Numerically stable algorithms for the computation of reduced unit cells

ACTA CRYSTALLOGRAPHICA SECTION A, Issue 1 2004
R. W. Grosse-Kunstleve
The computation of reduced unit cells is an important building block for a number of crystallographic applications, but unfortunately it is very easy to demonstrate that the conventional implementation of cell reduction algorithms is not numerically stable. A numerically stable implementation of the Niggli-reduction algorithm of K,ivý & Gruber [Acta Cryst. (1976), A32, 297,298] is presented. The stability is achieved by consistently using a tolerance in all floating-point comparisons. The tolerance must be greater than the accumulated rounding errors. A second stable algorithm is also presented, the minimumreduction, that does not require using a tolerance. It produces a cell with minimum lengths and all angles acute or obtuse. The algorithm is a simplified and modified version of the Buerger-reduction algorithm of Gruber [Acta Cryst. (1973), A29, 433,440]. Both algorithms have been enhanced to generate a change-of-basis matrix along with the parameters of the reduced cell. [source]


A DSP-like analogue processing unit for smart image sensors

INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 6 2002
Antoine Dupret
Abstract An electronic retina featuring DSP-like programmable analogue processing is addressed. The motivations for designing such an original smart image sensor are accounted for. The architecture of the circuit is described and then the two more important building blocks are detailed. Finally, the practical implementation and tests results are given so as to validate the approach. Copyright © 2002 John Wiley & Sons, Ltd. [source]


,O -Acyl isopeptide method' for peptide synthesis: Solvent effects in the synthesis of A,1,42 isopeptide using ,O -acyl isodipeptide unit'

JOURNAL OF PEPTIDE SCIENCE, Issue 12 2007
Atsuhiko Taniguchi
Abstract ,O -Acyl isopeptide method' is an efficient synthetic method for peptides. We designed ,O -acyl isodipeptide units', Boc-Ser/Thr(Fmoc-Xaa)-OH, as important building blocks to enable routine use of the O -acyl isopeptide method. In the synthesis of an A,1,42 isopeptide using O -acyl isodipeptide unit Boc,Ser(Fmoc,Gly),OH, a side reaction, resulting in the deletion of Ser26 in the O -acyl isopeptide structure, was noticed during coupling of the unit. We observed that the side reaction occurred during the activation step and was solvent-dependent. In DMF or NMP, an intramolecular side reaction, originating from the activated species of the unit, occurred during the activation step. In non-polar solvents such as CHCl3 or CH2Cl2, the side reaction was less likely to occur. Using CH2Cl2 as solvent in coupling the unit, the target A,1,42 isopeptide was synthesized with almost no major side reaction. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd. [source]


Open clusters and the galactic disk

ASTRONOMISCHE NACHRICHTEN, Issue 5 2010
S. Röser
Abstract It is textbook knowledge that open clusters are conspicuous members of the thin disk of our Galaxy, but their role as contributors to the stellar population of the disk was regarded as minor. Starting from a homogenous stellar sky survey, the ASCC-2.5, we revisited the population of open clusters in the solar neighbourhood from scratch. In the course of this enterprise we detected 130 formerly unknown open clusters, constructed volume- and magnitude-limited samples of clusters, re-determined distances, motions, sizes, ages, luminosities and masses of 650 open clusters. We derived the present-day luminosity and mass functions of open clusters (not the stellar mass function in open clusters), the cluster initial mass function CIMF and the formation rate of open clusters. We find that open clusters contributed around 40 percent to the stellar content of the disk during the history of our Galaxy. Hence, open clusters are important building blocks of the Galactic disk (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]