473 research outputs found
Game theoretic pricing models in hotel revenue management: an equilibrium choice-based conjoint analysis approach
This paper explores a game-theoretically founded approach to conjoint analysis that determines equilibrium room rates under differentiated price competition in an oligopolistic hotel market. Competition between hotels is specified in terms of market share functions that can be estimated using multinomial logit models of consumer choice. The approach is based on choice-based conjoint analysis that permits the estimation of attributes weights (“part-worths”) for an additive utility formulation of the utility function. From this, room rates that equilibrate the market, conditioned on the differences in services and facilities offered by competing hotels, can be determined. The approach is illustrated by an example
The Story Behind Bankruptcy: When Business Gets Personal
The number of bankruptcies in a specific period, and levels of debt, are well documented but little is known about the consequences of bankruptcies beyond the numbers. In this study, Dutch entrepreneurs who went through debt rescheduling after personal bankruptcy, were interviewed in order to gain an understanding of the private, personal and social implications of bankruptcy. Recently, systematic investigations of the implications of bankruptcy have been published. However, research has not yet taken the phenomenological experience of the bankrupt entrepreneur into account. Insights into these experiences are of critical importance for obtaining a comprehensive understanding of the impact of the bankruptcy process, and for engaging in a meaningful reform of bankruptcy law. During the interviews in this study, the entrepreneurs reflected on the early days of their business venture, the moment of first detecting the prospect of business failure, their personal experiences during business failure, and the aftermath of bankruptcy and debt rescheduling. The findings indicate that a bankruptcy experience can be compared to losing a loved one: a psychological process similar to mourning. The findings show that a lack of empathy, respect and transparency by formal institutional representatives such as judges, trustees and administrators is seen by the entrepreneurs as ‘emotional punishment’, and can be considered as a major source of their grief. Because of this grief, the bankruptcy and debt rescheduling experience can be extremely stressful causing severe psychological and physical distress. Implications for theory and practice are discussed. Coherent privaatrech
Correlation of structural and spectroscopic properties of a photosynthetic reaction center
Polarized spectra of absorption and light-induced absorbance changes are presented for the crystallized reaction centers of Rhodopseudomonas viridis. We find that a model based on extended dipole interaction between all six pigments is capable of interpreting detailed features such as the contributions from the individual pigments to the various absorption peaks. Even though the pigments are arranged in approximate C2 symmetry, the optical spectra together with the calculations reflect deviations from this symmetry, which may be important in understanding the electron pathway
Analysis of Diffusion of Ras2 in Saccharomyces cerevisiae Using Fluorescence Recovery after Photobleaching
Binding, lateral diffusion and exchange are fundamental dynamic processes
involved in protein association with cellular membranes. In this study, we
developed numerical simulations of lateral diffusion and exchange of
fluorophores in membranes with arbitrary bleach geometry and exchange of the
membrane localized fluorophore with the cytosol during Fluorescence Recovery
after Photobleaching (FRAP) experiments. The model simulations were used to
design FRAP experiments with varying bleach region sizes on plasma-membrane
localized wild type GFP-Ras2 with a dual lipid anchor and mutant GFP-Ras2C318S
with a single lipid anchor in live yeast cells to investigate diffusional
mobility and the presence of any exchange processes operating in the time scale
of our experiments. Model parameters estimated using data from FRAP experiments
with a 1 micron x 1 micron bleach region-of-interest (ROI) and a 0.5 micron x
0.5 micron bleach ROI showed that GFP-Ras2, single or dual lipid modified,
diffuses as single species with no evidence of exchange with a cytoplasmic
pool. This is the first report of Ras2 mobility in yeast plasma membrane. The
methods developed in this study are generally applicable for studying diffusion
and exchange of membrane associated fluorophores using FRAP on commercial
confocal laser scanning microscopes.Comment: Accepted for publication in Physical Biology (2010). 28 pages, 7
figures, 3 table
Separation of collagen cyanogen bromide-derived peptides by reversed-phase high-performance liquid chromatography
Immunohistochemical localization of collagen types I and VI in human skin wounds
A total of 74 human skin wounds were investigated and collagen types I and VI were localized in the wound area by immunohistochemistry. Collagen type I appeared in the form of ramifying string-like structures after approximately 5–6 days, but positive reactions in the form of a spot-like staining around isolated fibroblasts also occurred in a skin wound aged 4 days. Collagen VI was detectable after a post-infliction interval of at least 3 days showing a strongly positive reacting network associated with fibroblasts in the wound area. Both collagens appeared almost constantly after a wound age of 6–7 clays and could also be found in wounds aged a few months. Therefore, although a positive reaction for collagen type I in the form of string-like and ramifying structures around wound fibroblasts indicates a wound age of at least 5–6 days, a spot-like positive staining for collagen type I cannot exclude a wound age of at least 4 days. A positive staining for collagen type VI represents a post-infliction time of 3 days or more. The almost constant appearance of these collagen types suggests that negative results in a sufficient number of specimens indicate a wound age of less than 6–7 days, but cannot completely exclude longer post-infliction intervals. Since collagen type I and VI are also found in the granulation/scar tissue of lesions with advanced wound age, the immunohistochemical analysis of these proteins provides no further information for an age determination of older skin wounds
Overexpression of the class D MADS-box gene Sl-AGL11 impacts fleshy tissue differentiation and structure in tomato fruits
MADS-box transcription factors are key elements of the genetic networks controlling flower and fruit development. Among these, the class D clade gathers AGAMOUS-like genes which are involved in seed, ovule, and funiculus development. The tomato genome comprises two class D genes, Sl-AGL11 and Sl-MBP3 , both displaying high expression levels in seeds and in central tissues of young fruits. The potential effects of Sl-AGL11 on fruit development were addressed through RNAi silencing and ectopic expression strategies. Sl-AGL11-down-regulated tomato lines failed to show obvious phenotypes except a slight reduction in seed size. In contrast, Sl-AGL11 overexpression triggered dramatic modifications of flower and fruit structure that include: the conversion of sepals into fleshy organs undergoing ethylene-dependent ripening, a placenta hypertrophy to the detriment of locular space, starch and sugar accumulation, and an extreme softening that occurs well before the onset of ripening. RNA-Seq transcriptomic profiling high-lighted substantial metabolic reprogramming occurring in sepals and fruits, with major impacts on cell wall-related genes. While several Sl-AGL11-related phenotypes are reminiscent of class C MADS-box genes (TAG1 and TAGL1), the modifications observed on the placenta and cell wall and the Sl-AGL11 expression pattern suggest an action of this class D MADS-box factor on early fleshy fruit development
Metabolic effects of a 13-weeks lifestyle intervention in older adults: The Growing Old Together Study
Analytical BioScience
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