Development time and new product sales: A contingency analysis of product innovativeness and price

Opposing theories and conflicting empirical results with regard to the effect of development time on new product sales suggest the need for a contingency analysis into factors affecting this relationship. This study uses a unique combination of accounting and perceptual data from 129 product development projects to test the combined contingency effect of product innovativeness and new product price on the relationship between development time and new product sales. The results show that for radically new products with short development times, price has no effect on new product sales. When the development time is long, price has a negative effect on the sales of radical new products. The findings additionally show that price has no effect on sales for incremental new products with short development times and a negative effect for incremental new products with long development times. Together, these findings shed new light on the relationship between development time and new product sales

Wide-Angle Seismic Imaging of Two Modes of Crustal Accretion in Mature Atlantic Ocean Crust

We present a high‐resolution 2‐D P‐wave velocity model from a 225‐km‐long active seismic profile, collected over ~60–75 Ma central Atlantic crust. The profile crosses five ridge segments separated by a transform and three nontransform offsets. All ridge discontinuities share similar primary characteristics, independent of the offset. We identify two types of crustal segment. The first displays a classic two‐layer velocity structure with a high gradient Layer 2 (~0.9 s$^{−1}$) above a lower gradient Layer 3 (0.2 s$^{−1}$). Here, PmP coincides with the 7.5 km s$^{−1}$ contour, and velocity increases to >7.8 km s$^{−1}$ within 1 km below. We interpret these segments as magmatically robust, with PmP representing a petrological boundary between crust and mantle. The second has a reduced contrast in velocity gradient between the upper and lower crust and PmP shallower than the 7.5 km s$^{−1}$ contour. We interpret these segments as tectonically dominated, with PmP representing a serpentinized (alteration) front. While velocity‐depth profiles fit within previous envelopes for slow‐spreading crust, our results suggest that such generalizations give a misleading impression of uniformity. We estimate that the two crustal styles are present in equal proportions on the floor of the Atlantic. Within two tectonically dominated segments, we make the first wide‐angle seismic identifications of buried oceanic core complexes in mature (>20 Ma) Atlantic Ocean crust. They have a ~20‐km‐wide “domal” morphology with shallow basement and increased upper crustal velocities. We interpret their midcrustal seismic velocity inversions as alteration and rock‐type assemblage contrasts across crustal‐scale detachment faults

Controlled In Meso Phase Crystallization – A Method for the Structural Investigation of Membrane Proteins

We investigated in meso crystallization of membrane proteins to develop a fast screening technology which combines features of the well established classical vapor diffusion experiment with the batch meso phase crystallization, but without premixing of protein and monoolein. It inherits the advantages of both methods, namely (i) the stabilization of membrane proteins in the meso phase, (ii) the control of hydration level and additive concentration by vapor diffusion. The new technology (iii) significantly simplifies in meso crystallization experiments and allows the use of standard liquid handling robots suitable for 96 well formats. CIMP crystallization furthermore allows (iv) direct monitoring of phase transformation and crystallization events. Bacteriorhodopsin (BR) crystals of high quality and diffraction up to 1.3 Å resolution have been obtained in this approach. CIMP and the developed consumables and protocols have been successfully applied to obtain crystals of sensory rhodopsin II (SRII) from Halobacterium salinarum for the first time

Type I restriction enzymes and their relatives

Type I restriction enzymes (REases) are large pentameric proteins with separate restriction (R), methylation (M) and DNA sequence-recognition (S) subunits. They were the first REases to be discovered and purified, but unlike the enormously useful Type II REases, they have yet to find a place in the enzymatic toolbox of molecular biologists. Type I enzymes have been difficult to characterize, but this is changing as genome analysis reveals their genes, and methylome analysis reveals their recognition sequences. Several Type I REases have been studied in detail and what has been learned about them invites greater attention. In this article, we discuss aspects of the biochemistry, biology and regulation of Type I REases, and of the mechanisms that bacteriophages and plasmids have evolved to evade them. Type I REases have a remarkable ability to change sequence specificity by domain shuffling and rearrangements. We summarize the classic experiments and observations that led to this discovery, and we discuss how this ability depends on the modular organizations of the enzymes and of their S subunits. Finally, we describe examples of Type II restriction–modification systems that have features in common with Type I enzymes, with emphasis on the varied Type IIG enzymes

A routine device for high resolution bottom water sampling

AbstractA large variety of biotic and abiotic processes take place close to the sediment-water interface, causing and being affected byphysical, biological and chemical gradients below and above this transition zone. Adequate sampling of this environment isessential for a comprehensive understanding of the complex sea floor ecological systems. The multi-horizon bottom watersampler (BoWaSnapper) presented here was developed for instantaneous sampling of the transition zone above the seafloor andcan be deployed in all types of water bodies from coastal seas to full ocean depth (6000 m). The intention was to construct aninstrument that could bridge the gap between the sampling of the bottom water column by conventional CTD rosette andsediment sampling gear such as a multiple corer.The BoWaSnapper was designed to be operated on any research ship?s wire and allows time-efficient high-resolutionsampling of bottom water. The bottommost 2 m are sampled with six vertically adjustable bottles. Prior to closure, the bottlesare aligned with the bottom current by means of a vane and flushed by bottom water for several minutes. This ensures thatparticles dispersed upon the touch-down of the BoWaSnapper are flushed away. An electronic mechanism, activated by abottom switch, initiates bottle closure after a delay pre-selected by the user. As illustrated by several examples, the transparentbottles (6 L volume each) allow the determination of particle concentrations as well as the analysis of solutes such as nutrients,dissolved gases, and natural radiotracers. Although the sampler is universally suitable for seafloor environments, its specialdomain is characterised by steep geochemical gradients such as cold vents and submarine groundwater discharge.Keywords: Bottom water; Benthic boundary layer; Water samplers; Vertical distribution; Solutes; Particle concentratio

On a sequence of fast decreasing polynomial operators

Let f be a piecewise analytic function on the unit interval (respectively, the unit circle of the complex plane). Starting from the Chebyshev (respectively, Fourier) coefficients of f, we construct a sequence of fast decreasing polynomials (respectively, trigonometric polynomials) which “detect ” the points where f fails to be analytic, provided f is not infinitely differentiable at these points

Sites for Interaction between Gal80p and Gal1p in Kluyveromyces latis: Structural Model of Galactokinase based on Homology to the GHMP Protein Family

The induction of transcription of the galactose genes in yeast involves the galactose-dependent binding of ScGal3p (in Saccharomyces cerevisiae) or KlGal1p (in Kluyveromyces lactis) to Gal80p. This binding abrogates Gal80's inhibitory effect on the activation domain of Gal4p, which can then activate transcription. Here, we describe the isolation and characterization of new interaction mutants of K. lactis GAL1 and GAL80 using a two-hybrid screen. We present the first structural model for Gal1p to be based on the published crystal structures of other proteins belonging to the GHMP (galactokinase, homoserine kinase, mevalonate kinase and phosphomevalonate kinase) kinase family and our own X-ray diffraction data of Gal1p crystals at 3 Angstrom resolution.The locations of the various mutations in the modelled Gal1p structure identify domains involved in the interaction with Gal80p and provide a structural explanation for the phenotype of constitutive GAL1 mutations. (C) 2003 Elsevier Ltd. All rights reserved

Structural basis for the excision repair of alkylation-damaged DNA

Base-excision DNA repair proteins that target alkylation damage act on a variety of seemingly dissimilar adducts, yet fail to recognize other closely related lesions. The 1.8 Angstrom crystal structure of the monofunctional DNA glycosylase AlkA (E. coli 9-methyladenine-DNA glycosylase II) reveals a large hydrophobic cleft unusually rich in aromatic residues. An Asp residue projecting into this cleft is essential for catalysis, and it governs binding specificity for mechanism-based inhibitors. We propose that AlkA recognizes electron-deficient methylated bases through pi-donor/acceptor interactions involving the electron-rich aromatic cleft. Remarkably, AlkA is similar in fold and active site location to the bifunctional glycosylase/lyase endonuclease III, suggesting the two may employ fundamentally related mechanisms for base excisionclos