The beta function of the multichannel Kondo model

The beta function of the multichannel Kondo model is calculated exactly in the limit of large spin N and channel number M=gamma*N, with constant gamma. There are no corrections in any finite order of 1/N. One zero is found at a finite coupling strength, showing directly the Non--Fermi liquid behavior of the model. This renormalization group flow allows to introduce a variational principle for the entropy, to obtain the low temperature thermodynamics. Such in particular the low temperature thermodynamics of the non--crossing approximation to the Kondo model becomes accessible.Comment: 4 page

Kinks in the Kondo problem

We find the exact quasiparticle spectrum for the continuum Kondo problem of $k$ species of electrons coupled to an impurity of spin $S$. In this description, the impurity becomes an immobile quasiparticle sitting on the boundary. The particles are ``kinks'', which can be thought of as field configurations interpolating between adjacent wells of a potential with $k+1$ degenerate minima. For the overscreened case $k>2S$, the boundary has this kink structure as well, which explains the non-integer number of boundary states previously observed. Using simple arguments along with the consistency requirements of an integrable theory, we find the exact elastic $S$-matrix for the quasiparticles scattering among themselves and off of the boundary. This allows the calculation of the exact free energy, which agrees with the known Bethe ansatz solution.Comment: 9 pages +1 figur

Non-quasiparticle states in the core level spectra of ferromagnetic semiconductors and half-metallic ferromagnets

The Green's functions that determine x-ray spectra are calculated in the s-d exchange model of a saturated conducting ferromagnet in the presence of the core hole. A possibility to observe non-quasiparticle (NQP) states in the core level (x-ray absorption, emission and photoelectron) spectroscopy is demonstrated. It is shown that NQP contributions to resonant x-ray scattering spectra can be considerably enhanced by core hole effects in comparison with those to the density of states.Comment: 13 pages, 7 figures, final versio

The Effective Particle-Hole Interaction and the Optical Response of Simple Metal Clusters

Following Sham and Rice [L. J. Sham, T. M. Rice, Phys. Rev. 144 (1966) 708] the correlated motion of particle-hole pairs is studied, starting from the general two-particle Greens function. In this way we derive a matrix equation for eigenvalues and wave functions, respectively, of the general type of collective excitation of a N-particle system. The interplay between excitons and plasmons is fully described by this new set of equations. As a by-product we obtain - at least a-posteriori - a justification for the use of the TDLDA for simple-metal clusters.Comment: RevTeX, 15 pages, 5 figures in uufiles format, 1 figure avaible from [email protected]

The international declaration on the human right to nutritional care: A global commitment to recognize nutritional care as a human right

Access to nutritional care is frequently limited or denied to patients with disease-related malnutrition (DRM), to those with the inability to adequately feed themselves or to maintain their optimal healthy nutritional status which goes against the fundamental human right to food and health care. That is why the International Working Group for Patient's Right to nutritional care is committed to promote a human rights based approach (HRBA) in the field of clinical nutrition. Our group proposed to unite efforts by launching a global call to action against disease-related malnutrition through The International Declaration on the Human Right to Nutritional Care signed in the city of Vienna during the 44th ESPEN congress on September 5th 2022. The Vienna Declaration is a non-legally binding document that sets a shared vision and five principles for implementation of actions that would promote the access to nutritional care. Implementation programs of the Vienna Declaration should be promoted, based on international normative frameworks as The United Nations (UN) 2030 Agenda for Sustainable Development, the Rome Declaration of the Second International Conference on Nutrition and the Working Plan of the Decade of Action on Nutrition 2016–2025. In this paper, we present the general background of the Vienna Declaration, we set out an international normative framework for implementation programs, and shed a light on the progress made by some clinical nutrition societies. Through the Vienna Declaration, the global clinical nutrition network is highly motivated to appeal to public authorities, international governmental and non-governmental organizations and other scientific healthcare societies on the importance of optimal nutritional care for all patients

Discrete time model for two-machine one-buffer transfer lines with restart policy

Abstract The paper deals with analytical modeling of transfer lines consisting of two machines decoupled by one finite buffer. In particular, the case in which a control policy (referred as "restart policy") aiming to reduce the blocking frequency of the first machine is addressed. Such a policy consists of forcing the first machine to remain idle (it cannot process parts) each time the buffer gets full until it empties again. This specific behavior can be found in a number of industrial production systems, especially when some machines are affected by outage costs when stops occur. The two-machine one-buffer line is here modeled as a discrete time Markov process and the two machines are characterized by the same operation time. The analytical solution of the model is obtained and mathematical expressions of the most important performance measures are provided. Some significant remarks about the effect of the proposed restart policy on the behavior of the system are also pointed out

Business Models and E-Services: an Ontological Approach in a Cross-border Environment

Monograph's chapter

The level of air pollution in the impact zone of coal-fired power plant (Karaganda City) using the data of geochemical snow survey (Republic of Kazakhstan)

Coal-fired power plants emissions impact the air quality and human health. Of great significance is assessment of solid airborne particles emissions from those plants and distance of their transportation. The article presents the results of air pollution assessment in the zone of coal-fired power plant (Karaganda City) using snow survey. Based on the mass of solid airborne particles deposited in snow, time of their deposition on snow at the distance from 0.5 to 4.5 km a value of dust load has been determined. It is stated that very high level of pollution is observed at the distance from 0.5 to 1 km. there is a trend in decrease of dust burden value with the distance from the stacks of coal-fired power plant that may be conditioned by the particle size and washing out smaller ash particles by ice pellets forming at freezing water vapour in stacks of the coal-fired power plant. Study in composition of solid airborne particles deposited in snow has shown that they mainly contain particulates of underburnt coal, Al-Si- rich spheres, Fe-rich spheres, and coal dust. The content of the particles in samples decreases with the distance from the stacks of the coal-fired power plant

The measurement of household consumption expenditures

Household-level data on consumer expenditures underpin a wide range of empirical research in modern economics, spanning micro-and macroeconomics. This research includes work on consumption and saving, on poverty and inequality, and on risk sharing and insurance. We review different ways in which such data can be collected or captured: traditional detailed budget surveys, less onerous survey procedures that might be included in more general surveys, and administrative or process data. We discuss the advantages and difficulties of each approach and suggest directions for future investigation. © 2014 by Annual Reviews. All rights reserved