Mass-polariton theory of light in dispersive media

We have recently shown that the electromagnetic field in a medium is made of mass-polariton (MP) quasiparticles, which are quantized coupled states of the field and an atomic mass density wave (MDW) [Phys. Rev. A 95, 063850 (2017)]. In this work, we generalize the MP theory of light for dispersive media assuming that absorption and scattering losses are very small. Following our previous work, we present two different approaches to the theory of light: (1) the MP quasiparticle theory, which is derived by only using the fundamental conservation laws and the Lorentz transformation; (2) the classical optoelastic continuum dynamics (OCD), which is a generalization of the electrodynamics of continuous media to include the dynamics of the medium under the influence of optical forces. For the coupled MP state of a single photon and the medium, we obtain the total MP momentum of the Minkowski form while the field's share of the momentum is equal to the Abraham momentum. We also show that the correspondence between the MP and OCD models and the conservation of momentum at interfaces gives an unambiguous formula for the optical force. The dynamics of the light pulse and the related MDW lead to nonequilibrium of the medium and to relaxation of the atomic density by sound waves in the same way as for nondispersive media. We also carry out simulations for optimal measurements of atomic displacements related to the MDW in silicon. In the simulations, we consider different waveguide cross-sections and optical pulse widths and account for the breakdown threshold irradiance of materials. We also compare the MP theory to previous theories of the momentum of light in a dispersive medium. We show that our generalized MP theory resolves all the problems related to the Abraham-Minkowski dilemma in a dispersive medium

Feeding value of red clover-grass, Persian clover and common vetch for pigs

Red clover-grass, Persian clover, and common fetch that are generally grown for green manuring in organic cropping cycles, are also valuable forages for the feeding of pigs. They could substitute up to 30% of concentrates (on dry matter basis) in the feeding of growing pigs without negative impact on nitrogen (N) retention. This indicates that protein and amino acids of these legumes are well digested and utilised by the pigs. However, inclusion of roughage to pig diets shifts N utilisation so that N excretion to faeces is increased while N excretion to urine is decreased. Persian clover, in particular, is an intriguing roughage for pigs as its protein contains more amino acids that that of red clover-grass or common vetch. In addition, the digestibility of fibre is good in Persian clover, due to lower cellulose and lignin content in the fibre fraction. In practice, the voluntary feed intake of roughages remains lower, from 5% to 20% of pigs’ dry matter intake depending on the production phase

Feeding weaned piglets and growing-finishing pigs with diets based on mainly home-grown organic feedstuffs

In 2000, EU regulations for organic animal production set new guidelines for organic pig feeding requiring that this be based on mainly home-grown organic feedstuffs. Doubts were however raised whether these feeding regimes can maintain good growth performance and carcass quality of pigs. Three experiments were carried out to study different organic feeding regimes in weaned piglets and fattening pigs. In Experiment 1, we evaluated the use of peas and faba beans (0, 120, or 240 g kg-1) in diets for weaned piglets. Piglets fed pea diets performed as well as those fed the control diet, whereas the highest faba bean level resulted in reduced feed intake and growth performance. In Experiment 2, we studied the replacement (0, 33, or 67%) of rapeseed cake with blue lupins in fattening pig diets. The dietary lupin level had a quadratic effect on the weight gain of growing pigs, the best performance being observed at the 33% replacement level. However, dietary lupin level did not influence weight gain during the finishing period and total fattening. Back fat became softer with increasing dietary lupin levels. In Experiment 3, different protein supplements were compared in organic diets from weaning to slaughter. In two-phase feeding, the best performance was observed when whey protein was used as the protein supplement, followed by soya bean cake + whey protein and rapeseed cake + fish meal. The effects of a one-phase organic feeding regime with cold-pressed rapeseed cake + whey protein did not differ from those of the two-phase organic feeding regimes. Fattening pigs fed organic diets required from two to seven days longer to reach slaughter weight than those fed conventional diets. Pigs fed organic diets had fatter carcasses, but the eating quality of organic pork did not differ from that of pork from pigs fed conventional diets. Feed costs and the circulation rate of pigs, weaners in particular, were greater and carcass prices lower in the organic feeding regimes than in the conventional ones

From Aurora Borealis to Carpathians. Searching the Road to Regional and Rural Development

This paper aims at analysing the current regional and rural development tools available for Romania and Finland, as well as common encountered problems and differences in the local realities. The theoretical framework covers contemporary concepts typical for regional development and for rural development, such as learning regions, knowledge creation, social networks, innovation, bottom-up versus top-down approaches, and social, cultural and economical sustainable development. References to the specific problems encountered in remote areas or related to the communities with limited access to various resources are made and the existing policy trends are compared. Rural reality embraces very particular characteristics both in Romania and Finland. However, the history trends have been different and the actual situation of countries’ economy indicates a potential of learning in case of Romania and available solutions to similar problems in case of Finland. Still, transferring models and solutions is not an easy task and the particular challenges encountered in Nordic knowledge transfer projects are mentioned as a starting point helping to formulate assumptions related to the impediment to be expected in such a transfer case. Project Cycle Management in its newest version is brought in the discussion in an attempt to asses in what extent its recommendation could be useful and applied in the case of rural development programmes. The potential quality increase and the high technicality of the used terms are some of the analysed features of project Cycle Management. The concrete examples used in the paper are based on the interviews carried on by the authors in different and common research and evaluation projects in Finland and Romania. The paper brings into discussion the lacks existent in rural and regional development policy in an EU country and a accession one, as they appear using the initially proposed theoretical framework. Recommendations to be followed in the coming year are suggested in this paper evaluating comparatively some of the existent problems affecting local development

Feed intake and weight and body condition changes of 100% organically fed lactating sows

Energy and protein density of the 100 % organic lactation diet should be increased as early as from 3rd week of lactation onwards in order to minimize the weight loss of the sow during the at least 40 day lactation period. Feed amino acid balance from 22nd day of lactation should match the amount of live weight lost during the first 21 days of lactation. This should be supported by providing the piglets feed attractive enough to ensure their high dry feed intake during the late lactation period

Noiseless amplification of weak coherent fields without external energy

According to the fundamental laws of quantum optics, noise is necessarily added to the system when one tries to clone or amplify a quantum state. However, it has recently been shown that the quantum noise related to the operation of a linear phase-insensitive amplifier can be avoided when the requirement of a deterministic operation is relaxed. Nondeterministic noiseless linear amplifiers are therefore realizable. Usually nondeterministic amplifiers rely on using single photon sources. We have, in contrast, recently proposed an amplification scheme in which no external energy is added to the signal, but the energy required to amplify the signal originates from the stochastic fluctuations in the field itself. Applying our amplification scheme, we examine the amplifier gain and the success rate as well as the properties of the output states after successful and failed amplification processes. We also optimize the setup to find the maximum success rates in terms of the reflectivities of the beam splitters used in the setup. In addition, we discuss the nonidealities related to the operation of our setup and the relation of our setup with the previous setups.Comment: arXiv admin note: substantial text overlap with arXiv:1309.428

Generalized noise terms for the quantized fluctuational electrodynamics

The quantization of optical fields in vacuum has been known for decades, but extending the field quantization to lossy and dispersive media in nonequilibrium conditions has proven to be complicated due to the position-dependent electric and magnetic responses of the media. In fact, consistent position-dependent quantum models for the photon number in resonant structures have only been formulated very recently and only for dielectric media. Here we present a general position-dependent quantized fluctuational electrodynamics (QFED) formalism that extends the consistent field quantization to describe the photon number also in the presence of magnetic field-matter interactions. It is shown that the magnetic fluctuations provide an additional degree of freedom in media where the magnetic coupling to the field is prominent. Therefore, the field quantization requires an additional independent noise operator that is commuting with the conventional bosonic noise operator describing the polarization current fluctuations in dielectric media. In addition to allowing the detailed description of field fluctuations, our methods provide practical tools for modeling optical energy transfer and the formation of thermal balance in general dielectric and magnetic nanodevices. We use the QFED to investigate the magnetic properties of microcavity systems to demonstrate an example geometry in which it is possible to probe fields arising from the electric and magnetic source terms. We show that, as a consequence of the magnetic Purcell effect, the tuning of the position of an emitter layer placed inside a vacuum cavity can make the emissivity of a magnetic emitter to exceed the emissivity of a corresponding electric emitter

Thermal balance and photon-number quantization in layered structures

The quantization of the electromagnetic field in lossy and dispersive dielectric media has been widely studied during the last few decades. However, several aspects of energy transfer and its relation to consistently defining position-dependent ladder operators for the electromagnetic field in nonequilibrium conditions have partly escaped the attention. In this work we define the position-dependent ladder operators and an effective local photon-number operator that are consistent with the canonical commutation relations and use these concepts to describe the energy transfer and thermal balance in layered geometries. This approach results in a position-dependent photon-number concept that is simple and consistent with classical energy conservation arguments. The operators are formed by first calculating the vector potential operator using Green's function formalism and Langevin noise source operators related to the medium and its temperature, and then defining the corresponding position-dependent annihilation operator that is required to satisfy the canonical commutation relations in arbitrary geometry. Our results suggest that the effective photon number associated with the electric field is generally position dependent and enables a straightforward method to calculate the energy transfer rate between the field and the local medium. In particular, our results predict that the effective photon number in a vacuum cavity formed between two lossy material layers can oscillate as a function of the position suggesting that also the local field temperature oscillates. These oscillations are expected to be directly observable using relatively straightforward experimental setups in which the field-matter interaction is dominated by the coupling to the electric field

Faba beans in diets for growing-finishing pigs

Two experiments were carried out to study the effects of using the new faba bean (Vicia faba L.) cultivar Kontu as a domestic protein source for growing-finishing pigs.In Experiment 1,120 pigs were used with a body weight (BW)of 25–110 kg to study the effects of replacing 0, 25, 50, 75,and 100%of rapeseed meal with faba beans in barley +rapeseed meal based diets. Restrictedly fed grower and finisher diets contained 137–317 and 114–260 g kg–1 faba beans, respectively. A barley +soya bean meal based diet was included as a control. The replacement of rapeseed meal with faba beans exerted a quadratic effect on daily weight gain and on the feed conversion ratio of pigs in the growing period and during total fattening (P 0.05).In conclusion,inclusion of over 200 g kg–1 of faba beans in barley + rapeseed meal based diets is not recommended for growing pigs because it may result in reduced growth performance. Faba beans may influence meat colour,but this phenomenon should be investigated further

Kalsiumin ja fosforin lisäys vahvistaa nopeakasvuisten sikojen luita

Nopeasti, lähes kilon päivässä kasvaneiden lihasikojen liikuntapisteet ja etusorkan luiden murtolujuus paranivat, kun kalsiumin ja sulavan fosforin suositusta nostettiin 15-30 prosenttia. Lisäksi useiden luiden ominaispaino nousi. Kalsiumin ja fosforin saanti eivät vaikuttaneet sikojen kasvuun, rehuhyötysuhteeseen eikä teuraslaatuun.vo