The Impact of E-Commerce on Hotel Management: Evidences from a Sample of Tuscan Hotels

Presenting the results of a survey conducted in 2013 on a sample of 17 Tuscan hotels, this article analyses the impact of e-commerce on hotel management. It focuses on turnover, profitability and organization. The collected information suggests that the share of OTA related sales has become undoubtedly significant to the point to influence commercial policy and investment choices. The level of commissions applied by the new travel intermediaries is excessive according to hotels, which try to react by adopting directly controlled online booking systems. While profitability decreases, turnover and employment seem to be growing.Presentando una indagine condotta nel secondo semestre 2013 su un campione di 17 hotel aderenti a EBIT Toscana, questo articolo analizza l’impatto dell’e-commerce sulla gestione alberghiera, soffermandosi in particolare sugli aspetti che riguardano l’andamento del fatturato, la redditività e l’organizzazione. Le informazioni raccolte suggeriscono che la quota delle vendite intermediate dalle OTA è diventata indubbiamente significativa e tale da influenzare la politica commerciale e le scelte di investimento. Il livello delle commissioni applicate dai nuovi intermediari di viaggi è ritenuto eccessivo dagli alberghi del campione, che reagiscono adottando propri sistemi di prenotazione online. Mentre la redditività pare contrarsi, fatturato e dipendenti risultano invece in crescita

Eddy diffusivities of inertial particles under gravity

The large-scale/long-time transport of inertial particles of arbitrary mass density under gravity is investigated by means of a formal multiple-scale perturbative expansion in the scale-separation parametre between the carrier flow and the particle concentration field. The resulting large-scale equation for the particle concentration is determined, and is found to be diffusive with a positive-definite eddy diffusivity. The calculation of the latter tensor is reduced to the resolution of an auxiliary differential problem, consisting of a coupled set of two differential equations in a (6+1)-dimensional coordinate system (3 space coordinates plus 3 velocity coordinates plus time). Although expensive, numerical methods can be exploited to obtain the eddy diffusivity, for any desirable non-perturbative limit (e.g. arbitrary Stokes and Froude numbers). The aforementioned large-scale equation is then specialized to deal with two different relevant perturbative limits: i) vanishing of both Stokes time and sedimenting particle velocity; ii) vanishing Stokes time and finite sedimenting particle velocity. Both asymptotics lead to a greatly simplified auxiliary differential problem, now involving only space coordinates and thus easy to be tackled by standard numerical techniques. Explicit, exact expressions for the eddy diffusivities have been calculated, for both asymptotics, for the class of parallel flows, both static and time-dependent. This allows us to investigate analytically the role of gravity and inertia on the diffusion process by varying relevant features of the carrier flow, as e.g. the form of its temporal correlation function. Our results exclude a universal role played by gravity and inertia on the diffusive behaviour: regimes of both enhanced and reduced diffusion may exist, depending on the detailed structure of the carrier flow.Comment: 8 figures (12 plots), submitted to JF

DOTA-Derivatives of Octreotide Dicarba-Analogs with High Affinity for Somatostatin sst2,5 Receptors

In vivo somatostatin receptor scintigraphy is a valuable method for the visualization of human endocrine tumors and their metastases. In fact, peptide ligands of somatostatin receptors (sst's) conjugated with chelating agents are in clinical use. We have recently developed octreotide dicarba-analogs, which show interesting binding profiles at sst's. In this context, it was mandatory to explore the possibility that our analogs could maintain their activity also upon conjugation with DOTA. In this paper, we report and discuss the synthesis, binding affinity and conformational preferences of three DOTA-conjugated dicarba-analogs of octreotide. Interestingly, two conjugated analogs exhibited nanomolar affinities on sst(2) and sst(5) somatostatin receptor subtypes

Eddy diffusivity of quasi-neutrally-buoyant inertial particles

We investigate the large-scale transport properties of quasi-neutrally-buoyant inertial particles carried by incompressible zero-mean periodic or steady ergodic flows. We show howto compute large-scale indicators such as the inertial-particle terminal velocity and eddy diffusivity from first principles in a perturbative expansion around the limit of added-mass factor close to unity. Physically, this limit corresponds to the case where the mass density of the particles is constant and close in value to the mass density of the fluid, which is also constant. Our approach differs from the usual over-damped expansion inasmuch as we do not assume a separation of time scales between thermalization and small-scale convection effects. For a general flow in the class of incompressible zero-mean periodic velocity fields, we derive closed-form cell equations for the auxiliary quantities determining the terminal velocity and effective diffusivity. In the special case of parallel flows these equations admit explicit analytic solution. We use parallel flows to show that our approach sheds light onto the behavior of terminal velocity and effective diffusivity for Stokes numbers of the order of unity.Peer reviewe

The Role of e-Commerce in the Success of Low-cost Carriers

This research aims to answer the question if e-commerce favoured in a special way the growth of low-cost carriers within the civil aviation market. After defining low-cost and traditional carriers’ business models, data on transported passengers were collected for three countries (Italy, Germany and Spain) and confronted with the number of e-consumers. Despite a significant correlation in all the three markets, only in Italy our hypothesis has been supported by Granger causality, and the regression analysis allows to forecast a future characterized by a growing dominance of LCCs. Although the definition of an econometric model will require further studies, the distinctive features of the Italian market might represent a starting point for future research on the complex relationship between e-commerce and air transport

Effects of Local Corticosteroid Injection on Electrical Properties of Aβ-Fibers in Carpal Tunnel Syndrome

Very few data are available on the structural and functional effects of corticosteroids on peripheral nerve fibers. This paper is addressed to verify possible changes in the functional properties of myelinated Aβ fibers of the median nerve in carpal tunnel syndrome (CTS) after a local injection of triamcinolone acetate. Thirteen subjects affected by mild CTS and 13 controls were selected. Clinical, electrophysiological, and ultrasonographic (cross sectional area: CSA) data of the median nerve were quantified at 0 (pre-injection), and 1 month after triamcinolone injection at wrist. We analyzed the input-output curves constructed by plotting the response amplitude as a function of stimulus intensity. After corticosteroid injection, all patients experienced symptom relief, the median nerve CSA decreased, and the plateau value of the input-output curve was significant higher than before the treatment. Pre injection, we observed a significant inverse correlation between median nerve CSA and plateau value of the input-output curve, which remained significant even after the corticosteroid injection. The Aβ fibers with higher electrical threshold undergo conduction recovery after local corticosteroid injection. In CTS, combined mechanisms might contribute to resolution of symptoms: anti-edema/anti-inflammatory action and direct effect on the electrical properties of the nerve fibers

Sensory axons excitability changes in carpal tunnel syndrome after neural mobilization

Increased mechanosensitivity of the median nerve in carpal tunnel syndrome (CTS) has been demonstrated during upper limb tension test 1 (ULTT1) when the nerve is passively elongated. However, the neurophysiological changes of the sensory axons during stressing activities are unknown. The aim of present study was to verify possible changes in the excitability of median nerve afferent axons following nerve stress in elongation, in subjects with and without CTS. Eight CTS hands and eight controls were selected. Recruitment properties of the median nerve were studied by analyzing the relationship between the intensity of electrical stimulation and the size of motor response, before and after intermittent-repetitive neural mobilization. Only in CTS hands, after the intervention, the stimulus-response curve was strikingly abnormal: both plateau and slope values were significantly lower. During anatomical stress across the median nerve in elongation, compressive forces may exert mechanical traction on the median nerve, since it is 'tethered' at the carpal tunnel, resulting inactivation of Na(+) channels at the wrist, or impairment of energy-dependent processes which affect axonal conduction block. We conclude that in entrapment neuropathies, neural mobilization during nerve elongation may generate conduction failure in peripheral nerve. Our study supports specific considerations for patient education and therapeutic approaches

Design and solid phase synthesis of new DOTA conjugated (+)-biotin dimers planned to develop molecular weight-tuned avidin oligomers

Chemical modifications of the biotin carrier in pretargeted avidin-biotin radionuclide therapy may be of paramount importance for tuning the amount of the radioactivity delivered to cancer cells by labelled biotins. We report here the synthesis of a collection of new synthetic DOTA-constructs bearing two (+)-biotin molecules (bis-biotins), designed for the creation of multimeric Av units (tetramers) bonded to the antibody. All the syntheses were carried out following the solid phase strategy and growing the molecules on a Rink Amide resin. The biotin heads are connected through spacers containing PEG or non-PEG residues. Molecular modelling calculations suggested that the Av cross-linking ability of the bis-biotins depends mainly on the spacers length, with the best results being expected for arms affording distances in the range of 10-25 Å between the biotin carboxylate atoms, in the fully extended conformation. SEC-HPLC MALLS analysis of the products of our Av/bis-biotin reaction mixtures have confirmed this hypothesis. The bis-biotin 16, where the non-PEG linker ensured a distance of 26.7 Å between the biotin moieties, gave about 50% of Av oligomers while the shorter analogue 18 (19.5 Å) afforded 100% of an Av polymer containing about 21 protein units. Remarkably, the solubility of both the bis-biotins, i.e.16 and 18, in aqueous solutions was good and they showed excellent stability against the action of peptidases

Biotin derivatives carrying two chelating DOTA units. Synthesis, in vitro evaluation of biotinidases resistance, avidin binding, and radiolabeling tests

The synthesis of four biotin derivatives carrying two DOTA moieties for each ligand (BisDOTA set) is reported, for increasing radiation/dose ratio and improving efficiency in the pretargeted avidin-biotin radioimmunotherapy. The biotin-containing scaffold of two BisDOTAwas similar to the mono-DOTA derivative previously described. Then the scaffold was elongated by trifunctionalized spacers of different length and conjugated with one of the COOH groups of two DOTA. Two others were prepared starting from a on-resin lysine residue. The lysine R-NH2 was bonded to biotin, and then spacers were appended to the ε-NH2 and conjugated with two DOTA molecules. One compound contained a p-aminobenzoic acid spacer, which ensured higher head-to-tail distance and increased rigidity of the chain. These last two compounds had a very high ability to bond avidin and were labeled with 90Y at high specific activity. All the compounds were resistant to the action of serum biotinidases. ©2009 American Chemical Society