Search results for "STABILITY"
showing 10 items of 3085 documents
Invasion Ability and Disease Dynamics of Environmentally Growing Opportunistic Pathogens under Outside-Host Competition
2014
Most theories of the evolution of virulence concentrate on obligatory host-pathogen relationship. Yet, many pathogens replicate in the environment outside-host where they compete with non-pathogenic forms. Thus, replication and competition in the outside-host environment may have profound influence on the evolution of virulence and disease dynamics. These environmentally growing opportunistic pathogens are also a logical step towards obligatory pathogenicity. Efficient treatment methods against these diseases, such as columnaris disease in fishes, are lacking because of their opportunist nature. We present a novel epidemiological model in which replication and competition in the outside-hos…
The characterization of the capability of a balance
1996
A survey is given on important standardized definitions by which the capability of balances may be characterized. Some modifications are proposed with regard to the use of mass sensors for the continuous determination of mass variations. An important supplement is the ‘relative resolution’ introduced by Jenemann. Optimum values are presented.
The Other J.M.: John Maurice Clark and the Keynesian Revolution
2009
This paper suggests that Clark's views regarding the Keynesian Revolution illuminate some of the limitations of the Keynesian orthodoxy that developed after the war, bringing more institutional detail and a greater preoccupation with dynamic analysis. Clark developed the multiplier in dynamic terms and coupled it with the accelerator to provide the framework for business cycle theory. His analysis was not formalized and emphasized time lags and non-linearities, similar to Harrod. In addition, Clark was concerned with the inflationary consequences of Keynesian policies and he was dissatisfied with those mechanical interpretations of the income flow analysis, which came to be known as hydraul…
Effect of Foot Orthoses and Shoes in Parkinson's Disease Patients : A PRISMA Systematic Review
2021
[Abstract] Reduced plantar foot sensation, postural instability, and gait difficulties are characteristic of Parkinson´s disease patients. A systematic review was carried out to determine the effect of the different types of insoles and shoes in these patients. Several databases were used to search for relevant articles reporting Parkinson´s disease patients undergoing treatment with any type of insole and footwear. All titles and abstracts were reviewed independently by two reviewers and the available data were extracted. The study eligibility criteria were any type of experimental study that included Parkinson’s disease patients treated with any type of insole or footwear. Eight studies w…
Effect of linker distribution in the photocatalytic activity of multivariate mesoporous crystals
2021
The use of Metal-Organic Frameworks as crystalline matrices for the synthesis of multiple component or multivariate solids by the combination of different linkers into a single material has emerged as a versatile route to tailor the properties of single-component phases or even access new functions. This approach is particularly relevant for Zr6-MOFs due to the synthetic flexibility of this inorganic node. However, the majority of materials are isolated as polycrystalline solids, which are not ideal to decipher the spatial arrangement of parent and exchanged linkers for the formation of homogeneous structures or heterogeneous domains across the solid. Here we use high-throughput methodologi…
Thermal stability, structural properties and catalytic activity of Pd catalysts supported on Al2O3–CeO2–BaO mixed oxides prepared by sol–gel method
2003
Abstract Al2O3–CeO2–BaO oxides with constant Al/Ba mass ratio and increasing cerium content were prepared, using the sol–gel procedure, and calcined at 1000 °C for 5 h. The influence of barium oxide on the thermal stability and on the morphological and structural properties of the corresponding supports, in terms of increasing surface area of alumina and ceria dispersion, was studied. The corresponding Pd (1 wt.%) catalysts were prepared by a stepwise impregnation method with a solution of palladium acetylacetonate in benzene. Palladium was introduced in two sequential steps by impregnation 0.5 wt.% of Pd each time. The structural and textural properties of the materials were studied by X-r…
Ab Initio Study of BiFeO3: Thermodynamic Stability Conditions
2015
BiFeO3 is investigated intensively, mainly as a multiferroic material. In this paper, the state-of-the-art ab initio hybrid functional approach with atomic basis sets was employed for a study of the stability range of BiFeO3 with respect to its decomposition into binary oxides and elementary metals, as a function of temperature and oxygen partial pressure. The calculated atomic and electronic structure of BiFeO3 was compared with previous LDA+U calculations using plane-wave basis sets. Based on performed calculations, the phase diagram was constructed, which allows us to predict the stability region of stoichiometric BiFeO3.
Coordinating properties of the Cephalexine antibiotic. A potentiometric study of the complexes formation between Cephalexine and Co(II), Ni(II) and C…
1989
Abstract The formation of complexes between Co(II), Ni(II) and Cu(II) with Cephalexine has been investigated using potentiometric techniques. The stability constants of the complexes formed were calculated using the non-linear least-squares computer program SUPERQUAD. The obtained values were: Co(II) logβ1=2.40, logβMLOH=8.89; Ni(II) logβ1=2.80, logβ2=5.10, logβML2OH=12.09; Cu(II) logβ1=4.094 (25 °C, 0.1 M KNO3). The compound [Ni(CEX)(OH2)4]BPh4 has been synthesized and characterized by electronic, IR and NMR spectroscopies as well as by magnetic measurements. From these studies it is proposed that the Cephalexinate anion acts as a bidentate ligand and is bound to the metal ion through the …
Adaptive Fuzzy Control of a Process with Bifurcations
2002
Several fuzzy controllers with different structures have been considered for the control of systems with bifurcation. A mixed feedforward-feedback structure with some additional adaptation mechanisms have been checked by simulation in the control of a non-linear process constituted by a bubble column in which a slow kinetics auto-catalytic reaction takes place. Simulation results show the validity of some of the proposed controllers in avoiding the system reaching bifurcation and instability conditions.
MR3090050 Reviewed Belabbas, Mohamed Ali On global stability of planar formations. IEEE Trans. Automat. Control 58 (2013), no. 8, 2148–2153. (Reviewe…
2014
The focus of the paper is planar formation control, i.e. the design of control laws to stabilize agents at given distances from each other, under the constraint that the dynamics of each agent only depends on a subset of the other agents. The main contribution of the paper is the following: It is shown that a simple four-agent formation cannot be globally stabilized using twice differentiable control laws (this is not the case for three-agent formations), even up to sets of measure zero of initial conditions. This suggests that for four-agent formations one needs to look for control laws that are either not differentiable (or even not continuous) or of higher order in the dynamics. The appr…