Pion-Nucleon Scattering in Kadyshevsky Formalism: II Baryon Exchange Sector

In this paper, which is the second part in a series of two, we construct tree level baryon exchange and resonance amplitudes for $\pi N$ / $MB$-scattering in the framework of the Kadyshevsky formalism. We use this formalism to formally implement absolute pair suppression, where we make use of the method of Takahashi and Umezawa. The resulting amplitudes are Lorentz invariant and causal. We continue studying the frame dependence of the Kadyshevsky integral equation using the method of Gross and Jackiw. The invariant amplitudes, including those for meson exchange, are linked to the phase-shifts using the partial wave basis.Comment: 49 page

Pion-Nucleon Scattering in Kadyshevsky Formalism and Higher Spin Field Quantization

This thesis contains two parts. The first part deals with pion-nucleon/meson-baryon scattering in the Kadyshevsky formalism. This formalism is introduced and discussed. Problems may arise when derivative couplings and/or higher spin fields are used, especially when compared to the results in the Feynman formalism: unwanted contact terms pop-up. These terms are cancelled using the Gross and Jackiw or Takahashi and Umezawa method. The final results in both formalisms are therefore equal, causal and covariant. Formal incorporation of pair suppression in the baryon exchange sector is achieved using a method based on the Takahashi and Umezawa method. For the resulting tree level amplitudes, we have shown, to our knowledge for the first time, that they are causal, covariant and n-independent. Moreover, the amplitudes are just a factor 1/2 of the usual Feynman expressions. The amplitudes contain only posititve energy initial and final states, although it should be mentioned that negative energy is present inside an amplitude via the Delta propagator. The second part of this thesis deals with higher spin field quantization in the framework of Dirac's Constraint analysis. A full constraint analysis and quantization procedure is presented for the free spin 1,3/2 and 2 case and for the situation where these fields are coupled to auxiliary fields. The constructed propagators in the former case are shown to be non-covariant, as is well-known. Therefore, auxiliary fields coupled to gauge conditions of the free case are introduced in the Lagrangian. Now, the resulting propagators are covariant.Comment: 189 page

Distinct enzymatic responses in mice exposed to a range of low doses of ozone.

Short-term exposure of mice to low O3 doses, as defined by the product of concentration and exposure time (ct), was observed to induce alterations in two enzyme systems: first, that leading to changes in hepatic reduced ascorbic acid (RAA) content, and second to changes in plasma creatine phosphokinase (CPK) activity. RAA alterations were noticed immediately, 30 min and 120 min after termination of the exposure period, whereas CPK showed alterations immediately and 15 min after termination of the exposure. Later determinations, i.e., 24 hr after O3 exposure for RAA and 30 min after 03 exposure for CPK, revealed no significant differences when compared to control animals. Although differences in sensitivity existed, the dose response curves for both systems were more or less similar, showing a short decrease for the initial very low O3 doses, followed by a profound rise and a gradual decrease to control levels for subsequent ct doses. Exceptions were the 30 min curve for RAA and the immediate curve for CPK in so far as that both showed an additional depression. Neither plasma histamine nor plasma lactic acid dehydrogenase (LDH3) were observed to be altered by the range of O3 doses employed. These findings were explained on the basis of adaptation of the organism to a potentially noxious O3 stimulus by enhanced metabolic processes: a weak stimulus leading to only a small adjustment, and stronger stimuli to elevated enzyme activity as well. With increasing doses of O3 this elevation in enzyme activity was found to be gradually diminished, possibly due to a steadily growing demand, leaving the overshoot becoming continually smaller until a balanced state is achieved

Observation of the spin Peltier effect

We report the observation of the spin Peltier effect (SPE) in the ferrimagnetic insulator Yttrium Iron Garnet (YIG), i.e. a heat current generated by a spin current flowing through a Platinum (Pt)|YIG interface. The effect can be explained by the spin torque that transforms the spin current in the Pt into a magnon current in the YIG. Via magnon-phonon interactions the magnetic fluctuations modulate the phonon temperature that is detected by a thermopile close to the interface. By finite-element modelling we verify the reciprocity between the spin Peltier and spin Seebeck effect. The observed strong coupling between thermal magnons and phonons in YIG is attractive for nanoscale cooling techniques.Comment: 5 pages, 3 figures, 4 pages supplementary information, 4 supplementary figure

Economic Development and Infrastructure: The Case of Balochistan Province

In designing a future road network, public budget constraints force administrations to make choices. The objective of economic development requires that both efficiency and equity are taken into account. The present analysis operationalises these two concepts by social and economic accessibility in Balochistan. It suggests priorities which can serve as an input for the design of the future road network

Improving the Students\u27 Writing Competence in a Second Language Acquisition Through the Implementation of Lesson Study

Writing is the most difficult skill for second language learners. It can be seen, for example, they always make ageneralization, simplification, less of knowing vocabularies, punctuation, spelling, and grammar. This paper will describe improving the students\u27 writing competence in second language acquisition through the implementation of lesson study in faculty of language education of Indraprasta PGRI University of Jakarta. This research uses qualitative approach and the data taken from the students who are studying writing in the class. In applying lesson study, lecturer model explains about the materials based on the syllabus of the subject. The students are also given tasks in their groups. The observers watch and write about the students and assist them. After doing this, the observers discuss about the class with the lecturer model. By doing the implementation of Lesson Study, the students can work in group together, the class is so inspiring, they feel satisfied with the explanation of the lecturer model and havegood impact to improve the students\u27 writing competence

Pion-Nucleon Scattering in Kadyshevsky Formalism: I Meson Exchange Sector

In a series of two papers we present the theoretical results of $\pi N$/meson-baryon scattering in the Kadyshevsky formalism. In this paper the results are given for meson exchange diagrams. On the formal side we show, by means of an example, how general couplings, i.e. couplings containing multiple derivatives and/or higher spin fields, should be treated. We do this by introducing and applying the Takahashi-Umezawa and the Gross-Jackiw method. For practical purposes we introduce the $\bar{P}$ method. We also show how the Takashashi-Umezawa method can be derived using the theory of Bogoliubov and collaborators and the Gross-Jackiw method is also used to study the $n$-dependence of the Kadyshevsky integral equation. Last but not least we present the second quantization procedure of the quasi particle in Kadyshevsky formalism.Comment: 29 page