860 resultados para New Venture Strategies
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This article highlights some of the links between pre-morbid personality and clinical features of dementia. Indeed, personality characteristics forge an individual's coping strategies and thus influence the expression of behavioural and psychiatric syndromes of dementia (BPSD) or its precursor stages. Some personality traits such as neuroticism may impact on cognitive decline. BPSD being among the most important determinants of a patient's and their proxies' burden, a better understanding of the links between pre-morbid personality characteristics and BPSD will help define care strategies.
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The prevalence of food allergy in children is increasing, in particular in its most severe presentation, i.e. anaphylaxis. Food allergy has an important impact on children's and their parent's quality of life, because of the fear of accidental ingestion and limitations of social activities. Quality of life questionnaires adapted to food allergy are now available, as well as new diagnostic procedures using recombinant technology. Their interpretation and their clinical correlation remain difficult, especially in children, in the absence of references values. Various oral and subcutaneous immunotherapy strategies are currently under evaluation, using modified or native allergens.
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Human embryonic stem (hES) cells represent a potential source for cell replacement therapy of many degenerative diseases. Most frequently, hES cell lines are derived from surplus embryos from assisted reproduction cycles, independent of their quality or morphology. Here, we show that hES cell lines can be obtained from poor-quality blastocysts with the same efficiency as that obtained from good- or intermediate-quality blastocysts. Furthermore, we show that the self-renewal, pluripotency, and differentiation ability of hES cell lines derived from either source are comparable. Finally, we present a simple and reproducible embryoid body-based protocol for the differentiation of hES cells into functional cardiomyocytes. The five new hES cell lines derived here should widen the spectrum of available resources for investigating the biology of hES cells and advancing toward efficient strategies of regenerative medicine.
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BACKGROUND: Knowledge in the aetiopathogeny of aortic disease helps to characterise aortic lesions better and determine the risk of evolution and therapeutic strategies as well. This article focusses on aneurysms and dissections, and excludes causes related to infection, systemic inflammatory diseases and trauma. METHODS AND RESULTS: The biomedical literature of the past 10 years has been reviewed here. Aortic diseases are heterogeneous along the aorta as far as their genetic determinants, contribution of smooth muscle cells, inflammation and thrombus formation are concerned. Degradation of extracellular matrix by proteases causing aortic disease is a 'terminal' event, modulated by genetic background, haemodynamic strain, cellular events and thrombus formation. New genetic determinants of aortic disease have been identified. Proteases degrading the aortic wall are derived from a variety of cell types in addition to macrophages, including neutrophils on the luminal thrombus, mesenchymal and endothelial cells in the wall. Smooth muscle cells contribute to aortic wall homeostasis against inflammation and proteolysis. The degradation of the wall is followed by, or paralleled with, a failure of aortic reconstruction. CONCLUSIONS: Aortic diseases are diverse, and involve a multiplicity of biological systems in the vascular wall and at the interface with blood. Future research needs to unravel distinct cellular and molecular mechanisms causing the clinical events, in particular, dissection, expansion of already formed aneurysms and rupture.
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We analyze the entry of a new product into a vertically differentiated market in which an entrant and an incumbent compete in prices. Here the entry-deterrence strategies of the incumbent firm rely on “limit qualities.” With a sequential choice of quality, a quality-dependent marginal production cost, and a fixed entry cost, we relate the entry-quality decision and the entry-deterrence strategies to the level of entry cost and the degree of consumer heterogeneity. Quality-dependent marginal production costs in the model entail the possibility of inferior-quality entry as well as an incumbent’s aggressive entry-deterrence strategies of increasing its quality level toward potential entry. Welfare evaluation confirms that social welfare is not necessarily improved when entry is encouraged rather than deterred.
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In the last decades, the globalized competition among cities and regions made them develop new strategies for branding and promoting their territory to attract tourists, investors, companies and residents. Major sports events - such as the Olympic Games, the FIFA World Cup or World and Continental Championships - have played an integral part in these strategies. Believing, with or without evidence, in the capacity of those events to improve the visibility and the economy of the host destination, many cities, regions and even countries have engaged in establishing sports events hosting strategies. The problem of the globalized competition in the sports events "market" is that many cities and regions do not have the resources - either financial, human or in terms of infrastructure - to compete in hosting major sports events. Consequently, many cities or regions have to turn to second-tier sports events. To organise those smaller events means less media coverage and more difficulty in finding sponsors, while the costs - both financial and in terms of services - stay high for the community. This paper analyses how Heritage Sporting Events (HSE) might be an opportunity for cities and regions engaged in sports events hosting strategies. HSE is an emerging concept that to date has been under-researched in the academic literature. Therefore, this paper aims to define the concept of HSE through an exploratory research study. A multidisciplinary literature review reveals two major characteristics of HSEs: the sustainability in the territory and the authenticity of the event constructed through a differentiation process. These characteristics, defined through multiple variables, give us the opportunity to observe the construction process of a sports event into a heritage object. This paper argues that HSEs can be seen as territorial resources that can represent a competitive advantage for host destinations. In conclusion, academics are invited to further research HSEs to better understand their construction process and their impacts on the territory, while local authorities are invited to consider HSEs for the branding and the promotion of their territory.
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Most of the novel targeted anticancer agents share classical characteristics that define drugs as candidates for blood concentration monitoring: long-term therapy; high interindividual but restricted intraindividual variability; significant drug-drug and drug- food interactions; correlations between concentration and efficacy/ toxicity with rather narrow therapeutic index; reversibility of effects; and absence of early markers of response. Surprisingly though, therapeutic concentration monitoring has received little attention for these drugs despite reiterated suggestions from clinical pharmacologists. Several issues explain the lack of clinical research and development in this field: global tradition of empiricism regarding treatment monitoring, lack of formal conceptual framework, ethical difficulties in the elaboration of controlled clinical trials, disregard from both drug manufacturers and public funders, limited encouragement from regulatory authorities, and practical hurdles making dosage adjustment based on concentration monitoring a difficult task for prescribers. However, new technologies are soon to help us overcome these obstacles, with the advent of miniaturized measurement devices able to quantify circulating drug concentrations at the point-of-care, to evaluate their plausibility given actual dosage and sampling time, to determine their appropriateness with reference to therapeutic targets, and to advise on suitable dosage adjustment. Such evolutions could bring conceptual changes into the clinical development of drugs such as anticancer agents, while increasing the therapeutic impact of population PK-PD studies and systematic reviews. Research efforts in that direction from the clinical pharmacology community will be essential for patients to receive the greatest benefits and the least harm from new anticancer treatments. The example of imatinib, the first commercialized tyrosine kinase inhibitor, will be outlined to illustrate a potential research agenda for the rational development of therapeutic concentration monitoring.
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BACKGROUND: There is a lack of evidence to direct and support nursing practice in the specialty of paediatric intensive care (PIC). The development of national PIC nursing research priorities may facilitate the process of undertaking clinical research and translating evidence into practice. PURPOSE: To (a) identify research priorities for the care of patients and their family as well as for the professional needs of PIC nurses, (b) foster nursing research collaboration, (c) develop a research agenda for PIC nurses. METHODS: Over 13 months in 2007-2008, a three-round questionnaire, using the Delphi technique, was sent to all specialist level registered nurses working in Australian and New Zealand PICUs. This method was used to identify and prioritise nursing research topics. Content analysis was used to analyse Round I data and descriptive statistics for Round II and III data. RESULTS: In Round I, 132 research topics were identified, with 77 research priorities (mdn>6, mean MAD(median) 0.68±0.01) identified in subsequent rounds. The top nine priorities (mean>6 and median>6) included patient issues related to neurological care (n=2), pain/sedation/comfort (n=3), best practice at the end of life (n=1), and ventilation strategies (n=1), as well as two priorities related to professional issues about nurses' stress/burnout and professional development needs. CONCLUSION: The research priorities identified reflect important issues related to critically ill patients and their family as well as to the nurses caring for them. These priorities can be used for the development of a research agenda for PIC nursing in Australia and New Zealand.
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Since the advent of high-throughput DNA sequencing technologies, the ever-increasing rate at which genomes have been published has generated new challenges notably at the level of genome annotation. Even if gene predictors and annotation softwares are more and more efficient, the ultimate validation is still in the observation of predicted gene product( s). Mass-spectrometry based proteomics provides the necessary high throughput technology to show evidences of protein presence and, from the identified sequences, confirmation or invalidation of predicted annotations. We review here different strategies used to perform a MS-based proteogenomics experiment with a bottom-up approach. We start from the strengths and weaknesses of the different database construction strategies, based on different genomic information (whole genome, ORF, cDNA, EST or RNA-Seq data), which are then used for matching mass spectra to peptides and proteins. We also review the important points to be considered for a correct statistical assessment of the peptide identifications. Finally, we provide references for tools used to map and visualize the peptide identifications back to the original genomic information.
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Abstract Accurate characterization of the spatial distribution of hydrological properties in heterogeneous aquifers at a range of scales is a key prerequisite for reliable modeling of subsurface contaminant transport, and is essential for designing effective and cost-efficient groundwater management and remediation strategies. To this end, high-resolution geophysical methods have shown significant potential to bridge a critical gap in subsurface resolution and coverage between traditional hydrological measurement techniques such as borehole log/core analyses and tracer or pumping tests. An important and still largely unresolved issue, however, is how to best quantitatively integrate geophysical data into a characterization study in order to estimate the spatial distribution of one or more pertinent hydrological parameters, thus improving hydrological predictions. Recognizing the importance of this issue, the aim of the research presented in this thesis was to first develop a strategy for the assimilation of several types of hydrogeophysical data having varying degrees of resolution, subsurface coverage, and sensitivity to the hydrologic parameter of interest. In this regard a novel simulated annealing (SA)-based conditional simulation approach was developed and then tested in its ability to generate realizations of porosity given crosshole ground-penetrating radar (GPR) and neutron porosity log data. This was done successfully for both synthetic and field data sets. A subsequent issue that needed to be addressed involved assessing the potential benefits and implications of the resulting porosity realizations in terms of groundwater flow and contaminant transport. This was investigated synthetically assuming first that the relationship between porosity and hydraulic conductivity was well-defined. Then, the relationship was itself investigated in the context of a calibration procedure using hypothetical tracer test data. Essentially, the relationship best predicting the observed tracer test measurements was determined given the geophysically derived porosity structure. Both of these investigations showed that the SA-based approach, in general, allows much more reliable hydrological predictions than other more elementary techniques considered. Further, the developed calibration procedure was seen to be very effective, even at the scale of tomographic resolution, for predictions of transport. This also held true at locations within the aquifer where only geophysical data were available. This is significant because the acquisition of hydrological tracer test measurements is clearly more complicated and expensive than the acquisition of geophysical measurements. Although the above methodologies were tested using porosity logs and GPR data, the findings are expected to remain valid for a large number of pertinent combinations of geophysical and borehole log data of comparable resolution and sensitivity to the hydrological target parameter. Moreover, the obtained results allow us to have confidence for future developments in integration methodologies for geophysical and hydrological data to improve the 3-D estimation of hydrological properties.
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L’èxit de l’iniciativa ciutadana europea (ICE) com a instrument de democràcia directa a nivell europeu està directament relacionat amb la seva promulgació. Els ciutadans d’arreu Europa han d’estar informats sobre aquest nou mecanisme per tal que es dugui a terme, la qual cosa suposa una dificultat. Aquest estudi qualitatiu ens mostra els recursos i problemes en la divulgació de les ICE. Una anàlisi basat en entrevistes amb diferents organitzadors d’aquestes ICE que ens dona algunes idees sobre les seves estratègies de comunicació, així com l’ús d’eines de comunicació i relacions amb els mitjans de comunicació. A banda de les dificultats lingüístiques i financeres hi ha altres obstacles més específics relacionats amb l’ICE.
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OBJECTIVE: Atrial fibrillation is a very common heart arrhythmia, associated with a five-fold increase in the risk of embolic strokes. Treatment strategies encompass palliative drugs or surgical procedures all of which can restore sinus rhythm. Unfortunately, atria often fail to recover their mechanical function and patients therefore require lifelong anticoagulation therapy. A motorless volume displacing device (Atripump) based on artificial muscle technology, positioned on the external surface of atrium could avoid the need of oral anticoagulation and its haemorrhagic complications. An animal study was conducted in order to assess the haemodynamic effects that such a pump could provide. METHODS: Atripump is a dome-shape siliconecoated nitinol actuator sewn on the external surface of the atrium. It is driven by a pacemaker-like control unit. Five non-anticoagulated sheep were selected for this experiment. The right atrium was surgically exposed, the device sutured and connected. Haemodynamic parameters and intracardiac ultrasound (ICUS) data were recorded in each animal and under three conditions; baseline; atrial fibrillation (AF); atripump assisted AF (aaAF). RESULTS: In two animals, after 20 min of AF, small thrombi appeared in the right atrial appendix and were washed out once the pump was turned on. Assistance also enhanced atrial ejection fraction. 31% baseline; 5% during AF; 20% under aaAF. Right atrial systolic surfaces (cm2) were; 5.2 +/- 0.3 baseline; 6.2 +/- 0.1 AF; 5.4 +/- 0.3 aaAF. CONCLUSION: This compact and reliable pump seems to restore the atrial "kick" and prevents embolic events. It could avoid long-term anticoagulation therapy and open new hopes in the care of end-stage heart failure.
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A long term study on the reproductive strategies of Formica lugubris (Formica rufa group) has revealed many new important facts. Within a supercolony the sex-ratio is strongly female biased. Some of the sexuals mate on the nest surface, whereas others fly from the nest. Those sexuals participating in flights aggregate in particular meadow sites (mating places). On these places females attract males by releasing a sex pheromone.
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RESUME L'hyperammonémie est particulièrement toxique pour le cerveau des jeunes patients et entraîne une atrophie corticale, un élargissement des ventricules et des défauts de myélinisation, responsables de retards mentaux et développementaux. Les traitements actuels se limitent à diminuer le plus rapidement possible le taux d'ammoniaque dans l'organisme. L'utilisation de traitements neuroprotecteurs pendant les crises d'hyperammonémie permettrait de contrecarrer les effets neurologiques de l'ammoniaque et de prévenir l'apparition des troubles neurologiques. Au cours de cette thèse, nous avons testé trois stratégies de neuroprotection sur des cultures de cellules en agrégats issues du cortex d'embryons de rats et traitées à l'ammoniaque. - Nous avons tout d'abord testé si l'inhibition de protéines intracellulaires impliquées dans le déclenchement de la mort cellulaire pouvait protéger les cellules de la toxicité de l'ammoniaque. Nous avons montré que L'exposition à l'ammoniaque altérait la viabilité des neurones et des oligodendrocytes, et activait les caspases, la calpaïne et la kinase-5 dépendante des cyclines (cdk5) associée à son activateur p25. Alors que l'inhibition pharmacologique des caspases et de la calpaïne n'a pas permis de protéger les cellules cérébrales, un inhibiteur de la cdk5, appelé roscovitine, a réduit significativement la mort neuronale. L'inhibition de la cdk5 semble donc être une stratégie thérapeutique prometteuse pour prévenir 1es effets toxiques de 1'ammoniaque sur les neurones. - Nous avons ensuite étudié les mécanismes neuroprotecteurs déclenchés par le cerveau en réponse à la toxicité de l'ammoniaque. Nous avons montré que l'ammoniaque induisait la synthèse du facteur neurotrophique ciliaire (CNTF) par les astrocytes, via l'activation de la protéine kinase (MIAPK) p38. D'autre part, l'ajout de CNTF a permis de protéger les oligodendrocytes mais pas les neurones des cultures exposées à l'ammoniaque, via les voies de signalisations JAK/STAT, SAPK/JNK et c-jun. - Dans une dernière partie, nous avons voulu contrecarrer, par l'ajout de créatine, le déficit énergétique cérébral induit par l'ammoniaque. La créatine a permis de protéger des cellules de type astrocytaire mais pas les cellules cérébrales en agrégats. Cette thèse amis en évidence que les stratégies de neuroprotection chez les patients hyperammonémiques nécessiteront de cibler plusieurs voies de signalisation afin de protéger tous les types cellulaires du cerveau. Summary : In pediatric patients, hyperammonemia is mainly caused by urea cycle disorders or other inborn errors of metabolism, and leads to neurological injury with cortical atrophy, ventricular enlargement and demyelination. Children rescued from neonatal hyperammonemia show significant risk of mental retardation and developmental disabilities. The mainstay of therapy is limited to ammonia lowering through dietary restriction and alternative pathway treatments. However, the possibility of using treatments in a neuroprotective goal may be useful to improve the neurological outcome of patients. Thus, the main objective of this work was to investigate intracellular and extracellular signaling pathways altered by ammonia tonicity, so as to identify new potential therapeutic targets. Experiments were conducted in reaggregated developing brain cell cultures exposed to ammonia, as a model for the developing CNS of hyperammonemic young patients. Theses strategies of neuroprotection were tested: - The first strategy consisted in inhibiting intracellular proteins triggering cell death. Our data indicated that ammonia exposure altered the viability of neurons and oligodendrocytes. Apoptosis and proteins involved in the trigger of apoptosis, such as caspases, calpain and cyclin-dependent kinase-5 (cdk5) with its activator p25, were activated by ammonia exposure. While caspases and calpain inhibitors exhibited no protective effects, roscovitine, a cdk5 inhibitor, reduced ammonia-induced neuronal death. This work revealed that inhibition of cdk5 seems a promising strategy to prevent the toxic effects of ammonia on neurons. - The second strategy consisted in mimicking, the endogenous protective mechanisms triggered by ammonia in the brain. Ammonia exposure caused an increase of the ciliary neurotrophic factor (CNTF) expression, through the activation of the p38 mitogen-activated protein kinase (MAPK) in astrocytes. Treatment of cultures exposed to ammonia with exogenous CNTF demonstrated strong protective effects on oligodendrocytes but not on neurons. These protective effects seemed to involve JAK/STAT, SAPK/JNK and c-jun proteins. - The third strategy consisted in preventing the ammonia-induced cerebral energy deficit with creatine. Creatine treatment protected the survival of astrocyte-like cells through MAPKs pathways. In contrast, it had no protective effects in reaggregated developing brain cell cultures exposed to ammonia. The present study suggests that neuroprotective strategies should optimally be directed at multiple targets to prevent ammonia-induced alterations of the different brain cell types.
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Most sedimentary modelling programs developed in recent years focus on either terrigenous or carbonate marine sedimentation. Nevertheless, only a few programs have attempted to consider mixed terrigenous-carbonate sedimentation, and most of these are two-dimensional, which is a major restriction since geological processes take place in 3D. This paper presents the basic concepts of a new 3D mathematical forward simulation model for clastic sediments, which was developed from SIMSAFADIM, a previous 3D carbonate sedimentation model. The new extended model, SIMSAFADIM-CLASTIC, simulates processes of autochthonous marine carbonate production and accumulation, together with clastic transport and sedimentation in three dimensions of both carbonate and terrigenous sediments. Other models and modelling strategies may also provide realistic and efficient tools for prediction of stratigraphic architecture and facies distribution of sedimentary deposits. However, SIMSAFADIM-CLASTIC becomes an innovative model that attempts to simulate different sediment types using a process-based approach, therefore being a useful tool for 3D prediction of stratigraphic architecture and facies distribution in sedimentary basins. This model is applied to the neogene Vallès-Penedès half-graben (western Mediterranean, NE Spain) to show the capacity of the program when applied to a realistic geologic situation involving interactions between terrigenous clastics and carbonate sediments.