Search results for "LIMIT"
showing 10 items of 2826 documents
Relevance of Oxygen Concentration in Stem Cell Culture for Regenerative Medicine
2019
The key hallmark of stem cells is their ability to self-renew while keeping a differentiation potential. Intrinsic and extrinsic cell factors may contribute to a decline in these stem cell properties, and this is of the most importance when culturing them. One of these factors is oxygen concentration, which has been closely linked to the maintenance of stemness. The widely used environmental 21% O2 concentration represents a hyperoxic non-physiological condition, which can impair stem cell behaviour by many mechanisms. The goal of this review is to understand these mechanisms underlying the oxygen signalling pathways and their negatively-associated consequences. This may provide a rationale…
Transition Dipole Orientation of Linear Polyenes: Semiempirical Models and Extrapolation to the Infinite Chain Limit
1999
Linear conjugated polyenes have an electronic transition dipole moment for the strongly allowed 1Ag to 1Bu electronic excitation that is not oriented along the major axis of the polyene chain. In this paper, the experimental values of this off-axis angle are compared to semiempirical and ab initio theoretical predictions. The semiempirical computations are shown to be reliable and are extended to long chains (n = 20). The results are then extrapolated to the infinite chain limit. A nonzero value of 6°−11° for the infinite polyene is suggested by this extrapolation but state of the art ab initio results for a series of small polyenes yield a zero asymptotic value.
A new approach to fuzzy sets: Application to the design of nonlinear time series, symmetry-breaking patterns, and non-sinusoidal limit-cycle oscillat…
2019
Abstract It is shown that characteristic functions of sets can be made fuzzy by means of the B κ -function, recently introduced by the author, where the fuzziness parameter κ ∈ R controls how much a fuzzy set deviates from the crisp set obtained in the limit κ → 0. As applications, we present first a general expression for a switching function that may be of interest in electrical engineering and in the design of nonlinear time series. We then introduce another general expression that allows wallpaper and frieze patterns for every possible planar symmetry group (besides patterns typical of quasicrystals) to be designed. We show how the fuzziness parameter κ plays an analogous role to temper…
Nanosensor for Sensitive Detection of the New Psychedelic Drug 25I-NBOMe.
2020
[EN] This work reports the synthesis, characterization, and sensing behavior of a hybrid nanodevice for the detection of the potent abuse drug 25I-NBOMe. The system is based on mesoporous silica nanoparticles, loaded with a fluorescent dye, functionalized with a serotonin derivative and capped with the 5-HT2A receptor antibody. In the presence of 25I-NBOMe the capping antibody is displaced, leading to pore opening and rhodamine B release. This delivery was ascribed to 5-HT2A receptor antibody detachment from the surface due to its stronger coordination with 25I-NBOMe present in the solution. The prepared nanodevice allowed the sensitive (limit of detection of 0.6 mm) and selective recogniti…
Parking Pricing for a Sustainable Transport System
2014
Abstract The purpose of this study has been the develop of a model for designing an efficient parking pricing policy. The aim is an intelligent control and management system of parking pricing integrated with a redefinition of the circulation scheme for a limited traffic zone in the Central Business District (CBD) of Palermo. The transport demand over the entire area of the town has been studied in order to design various parking pricing scenarios with the application of an additional cost on parking inside the selected area of the CBD. This area attracts most of the private vehicular traffic and it is characterized by university faculties, schools, hospitals, offices and commercial areas. …
Vehicle scheduling for rental-with-driver services
2021
Abstract In this paper, we introduce a new vehicle scheduling problem (VSP) with driver consistency faced by rental-with-driver companies. A weekly time-horizon is considered and a set of potential customers, each one associated with a list of required tasks, is assumed. The company can choose to accept or reject a customer, but if accepted, all required tasks must be performed by the same driver. A profit is associated with each customer. The goal is to maximize the company’s total profit, by respecting a list of daily and the weekly drivers’ workload limitations imposed by drivers’ contracts. We propose a mathematical formulation of the problem and design an exact solution method based on…
An Approach to Cadastre Map Quality Evaluation
2008
An approach to data quality evaluation is proposed, which is elaborated and implemented by State Land Service of the Republic of Latvia. The approach is based on opinion of Land Service experts about Cadastre map quality that depends on its usage points. Quality parameters of Cadastre map objects identified by experts and its limit values are used for evaluation. The assessment matrix is used, which allow to define Cadastre map quality that depends on its usage purpose. The matrix is used to find out, of what quality a Cadastre map should be in order to be used for the chosen purpose. The given approach is flexible, it gives a possibility to change sets of quality parameters and their limit…
An Approach to Cadastral Map Quality Evaluation in the Republic of Latvia
2009
An approach to cadastral map quality evaluation is proposed, which is elaborated and implemented by State Land Service of the Republic of Latvia. The approach is based on opinion of Land Service experts about cadastral map quality that depends on its usage points. Quality parameters of cadastral map objects identified by experts and its limit values are used for evaluation. The assessment matrix is used, which allow to define cadastral map quality that depends on its usage purpose. The matrix is used to find out, of what quality a cadastral map should be in order to be used for the chosen purpose. The given approach is flexible, it gives a possibility to change sets of quality parameters an…
Closedness Properties in EX-Identification of Recursive Functions
1998
In this paper we investigate in which cases unions of identifiable classes of recursive functions are also necessarily identifiable. We consider identification in the limit with bounds on mindchanges and anomalies. Though not closed under the set union, these identification types still have features resembling closedness. For each of them we find such n that 1) if every union of n - 1 classes out of U1;, . . ., Un is identifiable, so is the union of all n classes; 2) there are such classes U1;, . . ., Un-1 that every union of n-2 classes out of them is identifiable, while the union of n - 1 classes is not. We show that by finding these n we can distinguish which requirements put on the iden…
Unions of identifiable families of languages
1996
This paper deals with the satisfiability of requirements put on the identifiability of unions of language families. We consider identification in the limit from a text with bounds on mindchanges and anomalies. We show that, though these identification types are not closed under the set union, some of them still have features that resemble closedness. To formalize this, we generalize the notion of closedness. Then by establishing “how closed” these identification types are we solve the satisfiability problem.