Browsing by Issue Date, starting with "2008-11"
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- Strategy implementation: what is the failure rate?Publication . Cândido, Carlos; Santos, Sérgio Pereira dosStrategy implementation has attracted the interest of researchers from the strategic management field almost since its foundation and has been the subject of much debate, in part, due to the ‘high’ percentage of organisational strategies that fail. It is often claimed that 50 to 90 percent of strategic initiatives fail to succeed. These claims have often been used to propose new management tools and to dismiss others. As we intend to show, although these claims have had a significant impact in management practice and theory, they are, however, controversial. In this paper we aim to clarify why this is the case and to emphasise that any attempts to produce a generic estimate of the rate of failure based on the current state of affairs are of little practical value. To this purpose an extensive review of the literature is presented and discussed. Based on the analysis of this literature, we conclude that whilst it is widely acknowledged that the implementation of a new strategy can be a difficult task, nobody seems to really know what the true rate of implementation failure is. Much of this uncertainty is due to the fact that some of the estimates presented in the literature are based on evidence that is eitheroutdated, fragmentary, fragile, or just absent. Careful consideration is therefore advised before using these estimates to promote changes in the theory and/or practice of strategic management.
- Tight regulation of unstructured proteins: from transcript synthesis to protein degradationPublication . Gsponer, Jorg; Futschik, Matthias E.; Teichmann, Sarah A.; Babu, M. MadanAltered abundance of several intrinsically unstructured proteins ( IUPs) has been associated with perturbed cellular signaling that may lead to pathological conditions such as cancer. Therefore, it is important to understand how cells precisely regulate the availability of IUPs. We observed that regulation of transcript clearance, proteolytic degradation, and translational rate contribute to controlling the abundance of IUPs, some of which are present in low amounts and for short periods of time. Abundant phosphorylation and low stochasticity in transcription and translation indicate that the availability of IUPs can be finely tuned. Fidelity in signaling may require that most IUPs be available in appropriate amounts and not present longer than needed.
- Turismo electrónicoPublication . Ramos, Célia M. Q.; Rodrigues, Paulo M. M.; Perna, FernandoAs Tecnologias de Informação e de Comunicação (TIC) e o desenvolvimento do Turismo estão interligados. É difícil identificar onde as TIC geram ou facilitam as alterações na procura e na oferta turística. Estas providenciam as ferramentas e permitem a evolução da procura e da oferta turística facilitando a existência e elaboração de panfletos turísticos e na resolução de necessidades inerentes à actividade turística. Consequentemente, a actividade turística aumenta os requisitos de TIC, por expansão das suas necessidades e por requisição dos utilizadores, uma vez que os desenvolvimentos tecnológicos facilitam as funções dos trabalhadores deste sector.
- Evaluating signatures of glacial refugia for North Atlantic benthic marine taxaPublication . Maggs, Christine A.; Castilho, Rita; Foltz, David; Henzler, Christy; Jolly, Marc Taimour; Kelly, John; Olsen, Jeanine; Perez, Kathryn E.; Stam, Wytze; Vainola, Risto; Viard, Frederique; Wares, JohnA goal of phylogeography is to relate patterns of genetic differentiation to potential historical geographic isolating events. Quaternary glaciations, particularly the one culminating in the Last Glacial Maximum similar to 21 ka (thousands of years ago), greatly affected the distributions and population sizes of temperate marine species as their ranges retreated southward to escape ice sheets. Traditional genetic models of glacial refugia and routes of recolonization include these predictions: low genetic diversity in formerly glaciated areas, with a small number of alleles/haplotypes dominating disproportionately large areas, and high diversity including "private'' alleles in glacial refugia. In the Northern Hemisphere, low diversity in the north and high diversity in the south are expected. This simple model does not account for the possibility of populations surviving in relatively small northern periglacial refugia. If these periglacial populations experienced extreme bottlenecks, they could have the low genetic diversity expected in recolonized areas with no refugia, but should have more endemic diversity (private alleles) than recently recolonized areas. This review examines evidence of putative glacial refugia for eight benthic marine taxa in the temperate North Atlantic. All data sets were reanalyzed to allow direct comparisons between geographic patterns of genetic diversity and distribution of particular clades and haplotypes including private alleles. We contend that for marine organisms the genetic signatures of northern periglacial and southern refugia can be distinguished from one another. There is evidence for several periglacial refugia in northern latitudes, giving credence to recent climatic reconstructions with less extensive glaciation.
- Egg release and settlement patterns of dioecious and hermaphroditic fucoid algae during the tidal cyclePublication . Ladah, Lydia; Feddersen, F.; Pearson, G. A.; Serrão, EsterThe timing of gamete release by fucoid algae, although known to be restricted to calm days is not clearly understood within a circadian time scale. The need for externally fertilizing species to avoid gamete dilution suggests that in wave-exposed areas spawning may occur during particular tidal phases. However, this may differ between mating systems, as selfing species may be less affected by gamete dilution. In this study, two different approaches were used to determine when egg release occurs during the tidal cycle in two sister species with different mating systems. First, egg settlement of Fucus vesiculosus (dioecious) and Fucus spiralis (selfing hermaphrodite) was quantified on removable substrates (egg settlement disks) every day for 2 months and settlement patterns were used to statistically estimate the radius of a circle that would encompass 99% of each patch of settled eggs (the egg dispersal radius). Also, egg release was quantified every 2 h during the tidal cycle. A significantly larger egg dispersal radius (P < 0.02) was found for F. spiralis than F. vesiculosus, and this difference was somewhat site dependent with a greater difference between species in exposed sites. The egg dispersal radius was negatively correlated with significant wave height and positively correlated with sea surface temperature for both the species (P < 0.05), with a greater effect of both the factors for F. spiralis than for F. vesiculosus. Egg release during the tidal cycle was variable between species and experiments, with F. vesiculosus releasing more eggs, later in the day, and at a lower tide, than F. spiralis, which released fewer eggs, throughout the day and at all tides. The dioecious species, F. vesiculosus, may have developed a specific adaptation for timing the egg release to periods when emersed in exposed habitats to avoid rapid dilution of gametes that require outcrossing for fertilization. On the other hand, egg release for F. spiralis, which can self-fertilize, occurred both when emersed and immersed, suggesting this species has developed less synchrony with specific environmental factors. Site dependence also suggests local wave conditions can modulate timing of release. The data are consistent with the relaxation of the selective constraints of water motion on fertilization success in a selfing hermaphrodite, relative to an obligate outcrossing species. Results support the idea that species with different mating systems evolve different sensitivities to environmental cues for gamete release with specific implications for inbreeding and successful external fertilization in the ocean.