Exploring drivers of overnight stays and same-day visits in the tourism sector.

We employ mobile network data referred to the area of Lombardy in Italy to investigate alternative touristic behaviours, such as same-day visits and overnight stays in Italy. We show that larger availability of tourism accommodations, cultural and natural endowments are relevant factors explaining overnight stays. Conversely, temporary entertainment and transportation facilities increase municipalities attractiveness for same-day visits.

Data science in the design of public policies: dispelling the obscurity in matching policy demand and data offer.

Data Science (DS) is expected to deliver value for public governance. In a number of studies, strong claims have been made about the potential of big data and data analytics and there are now several cases showing their application in areas such as service delivery and organizational administration. The role of DS in policy-making has, on the contrary, still been explored only marginally, but it is clear that there is the need for greater investigation because of its greater complexity and its distinctive inter-organizational boundaries.

The dual biological identity of human beings and the naturalization of morality.

The last two centuries have been the centuries of the discovery of the cell evolution: in the XIX century of the germinal cells and in the XX century of two groups of somatic cells, namely those of the brain-mind and of the immune systems. Since most cells do not behave in this way, the evolutionary character of the brain-mind and of the immune systems renders human beings formed by t wo different groups of somatic cells, one with a deterministic and another with an indeterministic (say Darwinian) behavior. An inherent consequence is that of the generation, during ontogenesis, of a dual biological identity.

[Necessary sites: identical duplication of living organisms].

The paper deals with the concept of the identity of living organisms, a concept used up until now very ambiguously. The discussion rests on the combination of two concepts, one proposed by Munzer (1993) and another derived from the considerations of Riedl (1975). The first is the proposal that the identity of living organisms depends on the properties of their elementary constituents, such as cells and tissues, and that these properties, in turn, depend on those of their DNA and RNA.

The cement of medical thought. Evolutionary emergence and downward causation.

The aetio-pathogenetic sequences and the physio-pathological patterns of diabetes, emphysema, cholera, circulatory shock and thrombosis have been analysed with respect to an evolutionary interpretation. The diseases, although reflecting alterations of processes that can always be described in physico-chemical language, occur only at the level of biological systems which reflects the decodification of genomic project: the teleonomic projects that have been developed during evolution. The concepts of evolutionary emergence and of downward causation have been used to discuss the relationship between the molecular events responsible for the initiation of the disease, and the subsequent events responsible for the aetio-pathogenesis, for the systemic disarrangement and for the additional alterations of tissues and cells independent of the initial molecular events.

[Predicibility of scientific medicine. 1. The role of chaotic and evolutionary processes].

The deterministic processes, whether mechanicistic or statistic but not chaotic, have a high degree of predicibility in contrast with evolutionary processes. Following the methodological principle of C. Bernard of diseases as alterations of biochemical and physiological processes, medicine has been assigned to the area of the functional biological, i.

Adaptation and information in ontogenesis and phylogenesis. Increase of complexity and efficiency.

Adaptations during phylogenesis or ontogenesis can occur either by maintaining constant or by increasing the informational content of the organism. In the former case the increasing adaptations to external perturbation are achieved by increasing the rate of genome replication; the increased amount of DNA reflects an increase of total but not of law informational content. In the latter case the adaptations are achieved by either istructionist or evolutionary mechanism or a combination of both.

The nature of uncoupling by n-hexane, 1-hexanethiol and 1-hexanol in rat liver mitochondria.

We have analyzed the effects of n-hexane, 1-hexanethiol, and 1-hexanol on the coupled respiration of rat liver mitochondria. Incubation of mitochondria with n-hexane, 1-hexanethiol and 1-hexanol resulted in a stimulation, at low concentrations, and an inhibition, at high concentrations, of the state 4 mitochondrial respiration. Three criteria, all based on the comparison with the effect of DNP, have been used to establish whether the stimulation of respiration, at low concentrations of n-hexane, 1-hexanethiol, and 1-hexanol, depends on protonophoric mechanisms.

The nature of diseases: evolutionary, thermodynamic and historical aspects.

Physico-chemical sciences are dominated by the deterministic interpretation. Scientific medicine has generally been assigned to the area of functional biology and thence to the physico-chemical sciences. In as much as diseases are alterations of physiological processes, they share the ontological status of the latter.

Nature of respiratory stimulation in hyperthyroidism: the redox behaviour of cytochrome c.

Hyperthyroid mitochondria show an increased Km and Vmax in the high affinity phase of cytochrome oxidase kinetics. During inhibitor titrations, cytochrome c shows a different redox behaviour in hyperthyroid with respect to protonophore-treated euthyroid mitochondria. The observations are discussed in terms of a different regulation of electron input and output into the respiratory chain during slip and leak types of uncoupling.

The nature of mitochondrial respiration and discrimination between membrane and pump properties.

A new criterion is utilized for the interpretation of flow-force relationships in rat liver mitochondria. The criterion is based on the view that the nature of the relationship between the H+/O ratio and the membrane potential can be inferred from the relationship between ohmic-uncoupler-induced extra respiration and the membrane potential. Thus a linear relationship between extra respiration and membrane potential indicates unequivocally the independence of the H+/O ratio from the membrane potential and the leak nature of the resting respiration [Brand, Chien, and Diolez (1994) Biochem.

The effect of the protonmotive force on the redox state of mitochondrial cytochromes.

In the absence of kinetic limitations, as determined either by high substrate concentrations or by absence of respiratory chain inhibitors, we have observed that: (a) the relationship between the percentage reduction of the cytochromes and the protonmotive force is linear in the case of cytochrome c and biphasic in the case of cytochrome b, (b) the redox state of cytochrome c depends only on the membrane potential and not on the total proton motive force and (c) the alkalinization of the matrix enhances the extent of cytochrome c reduction because of the marked inhibitory effect on the cytochrome oxidase activity. Thus, although the redox states of the b, c and aa3 mitochondrial cytochromes depend on the protonmotive force, the quantitative correlation between the two parameters and the relative effects of the electrical and chemical components of the force differ among the various cytochromes.

The effect of respiration on the permeability of the mitochondrial membrane to ions.

1. The rates of cation uptake, for either organic cations such as tetrapropylammonium, TPA+, at variable tetraphenylboron concentrations, TPB-, or inorganic cations such as Mn2+, or K+ plus valinomycin, have been measured in mitochondria either respiring, under uncoupler titrations, or non-respiring, under variable K+ diffusion potentials. 2.

Mechanism of loss of thermodynamic control in mitochondria due to hyperthyroidism and temperature.

Incubation of normal mitochondria at 45 degrees C results in increases of respiration and of total apparent proton conductance (TAPC, respiration/proton motive force) and in an upward shift of the flow-force relationships. Similar effects are observed during operation of the redox proton pumps at different sites of the respiratory chain. These effects are accompanied by an almost equivalent increase of the passive proton conductance (PPC, proton leakage/proton motive force).

Tracking of proton flow during transition from anaerobiosis to steady state. 2. Effect of cation uptake on the response of a hydrophobic membrane bound pH indicator.

1. During aerobic cation uptake in liver mitochondria, the hydrophobic pH indicator bromothymol blue undergoes a multiphase response: phase 1 (rapid acidification), phase 2 (slow alkalinization), phase 3 (rapid alkalinization) and phase 4 (reacidification). 2.

Tracking of proton flow during transition from anaerobiosis to steady state. 1. Response of matrix pH indicators.

1. The kinetics of acidification and realkalinization of the matrix after addition of nigericin to respiring and non-respiring mitochondria, recorded by intramitochondrial pH indicators such as neutral red and 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein (BCECF), is complementary to that recorded by extramitochondrial pH indicators. The extent of acidification decreases with the logarithm of the KCl concentration and is inhibited by Pi and ammonium ions.

Activation of respiration and loss of thermodynamic control in hyperthyroidism. Is it due to increased slipping in mitochondrial proton pumps?

T3 administration increases the extent of non-linearity in the flow-force relationship between pump proton conductance and protonmotive force. The effect is present also at the ATPase proton pump. These effects are not accompanied by changes in passive proton conductance.

Phenylarsine oxide induces the cyclosporin A-sensitive membrane permeability transition in rat liver mitochondria.

This paper reports an investigation on the effects of the hydrophobic, bifunctional SH group reagent phenylarsine oxide (PhAsO) on mitochondrial membrane permeability. We show that PhAsO is a potent inducer of the mitochondrial permeability transition in a process which is sensitive to both the oxygen radical scavanger BHT and to cyclosporin A. The PhAsO-induced permeability transition is stimulated by Ca2+ but takes place also in the presence of EGTA in a process that maintains its sensitivity to BHT and cyclosporin A.

Flow-force relationships during energy transfer between mitochondrial proton pumps.

The effect of inhibitors of proton pumps, of uncouplers and of permeant ions on the relationship between input force, delta mu H+, and output flows of the ATPase, redox and transhydrogenase H(+)-pumps in submitochondrial particles was investigated. It is concluded that: (1) The decrease of output flow of the transhydrogenase proton pump, defined as the rate of reduction of NADP+ by NADH, is linearily correlated with the decrease of input force, delta mu H+, in an extended range of delta mu H+, independently of whether the H(+)-generating pump is the ATPase or a redox pump, or whether delta mu H+ is depressed by inhibitors of the H(+)-generating pump such as oligomycin or malonate, or by uncouplers. (2) The output flows of the ATPase and of the site I redox H(+)-pumps exhibit a steep dependence on delta mu H+.

Flux ratios and pump stoichiometries at sites II and III in liver mitochondria. Effect of slips and leaks.

Addition of bovine serum albumin to state 4 mitochondria results in a depression of the proton leak and of the resting respiration of 70 and 25%, respectively. The conductance membrane potential diagram, both in the ohmic and in the non-ohmic region, shows that in the presence of bovine serum albumin the level of ohmic conductance is lowered while that of non-ohmic conductance is increased toward higher delta psi values. The same effect is observed during operation of the different proton pumps.

Bulk phase proton fluxes during the generation of membrane potential in rat liver mitochondria.

The addition of oxygen to anaerobic rat liver mitochondria incubated at 15 degrees C in the absence of permeant cations produced negligible rapid H+ ejection, monitored spectroscopically with phenol red, which corresponded kinetically to the rise in delta psi, as monitored by merocyanine 540. Slow H+ translocation was observed under these conditions during the aerobic phase, the extent of which was proportional to the amount of oxygen added and the rate dependent on the rate of counter-ion movement. Measurement of H+ disappearance in the mitochondrial matrix, as monitored by neutral red, likewise showed little or no rapid H+ change in the absence of counter-ion movements.

On the nature of the uncoupling effect of fatty acids.

The effect of palmitic acid on the electrical potential differences delta psi across the inner mitochondrial membrane appears to depend on the medium in which mitochondria are incubated. In medium A (cf. Luvisetto et al.

Tracking of proton flow during transition from anaerobiosis to steady state in rat liver mitochondria.

(1) The hydrophobic pH indicator Bromthymol blue and the hydrophilic pH indicator Phenol red have been used to follow the redox-pump-linked proton flows during transition from anaerobiosis to static head. The domains monitored by the pH indicators, whether external or internal, and the localization of the dye, whether free or membrane bound, have been identified by recording the absorbance changes following addition of nigericin or valinomycin to anaerobic or aerobic mitochondria and the effects of permeant and impermeant buffers. (2) After addition of the H+/K+ exchanger, nigericin, to anaerobic mitochondria.