Boson-fermion mixtures inside an elongated cigar-shaped trap

We present mean-field calculations of the equilibrium state in a gaseous mixture of bosonic and spin-polarized fermionic atoms with repulsive or attractive interspecies interactions, confined inside a cigar-shaped trap under conditions such that the radial thickness of the two atomic clouds is approaching the magnitude of the s-wave scattering lengths. In this regime the kinetic pressure of the fermionic component is dominant. Full demixing under repulsive boson-fermion interactions can occur only when the number of fermions in the trap is below a threshold, and collapse under attractive interactions is suppressed within the range of validity of the mean-field model. Specific numerical illustrations are given for values of system parameters obtaining in 7Li-6Li clouds.Comment: 12 pages, 6 figure

The Degree of Financial Liberalization and Aggregated Stock-return Volatility in Emerging Markets

In this study, we address whether the degree of financial liberalization affects the aggregated total volatility of stock returns by considering the time-varying nature of financial liberalization. We also explore channels through which the degree of financial liberalization impacts aggregated total volatility. We document a negative relation to the degree of financial liberalization after controlling for size, liquidity, country, and crisis effects, especially for small and medium-sized markets. Moreover, the degree of financial liberalization transmits its negative impact on aggregated total volatility through aggregated idiosyncratic and local volatilities. Overall, our results provide evidence in favor of the view that the broadening of the investor base due to the increasing degree of financial liberalization causes a reduction in the total volatility of stock returns.return volatility;financial liberalization;market integration;volatility decomposition;emerging markets

Renormalization Group Analysis of a Gursey Model Inspired Field Theory II

Recently a model, which is equivalent to the scalar form of Gursey model, is shown to be a nontrivial field theoretical model when it is gauged with a SU(N) field. In this paper we study another model that is equivalent to the vector form of the Gursey model. We get a trivial theory when it is coupled with a scalar field. This result changes drastically when it is coupled with an additional SU(N) field. We find a nontrivial field theoretical model under certain conditions.Comment: 10 pages, 10 figures, revtex4, typos corrected, published versio

Role of Strong versus Weak Networks in Small Business Growth in an Emerging Economy

The study tests whether strong rather than weak ties account for small business growth in Turkey. Data were collected by means of a questionnaire filled out by the owners of small firms operating in four cities. Growth is comprised of two main areas, production expansion and knowledge acquisition. Results show that strong ties are positively related to both types of growth. In contrast, loose ties have no effect on small business growth in either area. This finding is attributed to the influence of the collectivistic nature of the mainstream Turkish culture, where owners of small businesses are likely to rely on in-groups rather than out-groups for advice and for financial support. Implications of relative absence of weak ties for small business growth and innovation in emerging economies are discussed. The findings suggest that culture should be included as a contingency variable in future studies of network strength and growth relationship. The paper also discusses the possible moderating role of affective and cognition-based trust in the relation of strong and weak ties to small business growth

Role of Strong versus Weak Networks in Small Business Growth in an Emerging Economy

Cataloged from PDF version of article.The study tests whether strong rather than weak ties account for small business growth in Turkey. Data were collected by means of a questionnaire filled out by the owners of small firms operating in four cities. Growth is comprised of two main areas, production expansion and knowledge acquisition. Results show that strong ties are positively related to both types of growth. In contrast, loose ties have no effect on small business growth in either area. This finding is attributed to the influence of the collectivistic nature of the mainstream Turkish culture, where owners of small businesses are likely to rely on in-groups rather than out-groups for advice and for financial support. Implications of relative absence of weak ties for small business growth and innovation in emerging economies are discussed. The findings suggest that culture should be included as a contingency variable in future studies of network strength and growth relationship. The paper also discusses the possible moderating role of affective and cognition-based trust in the relation of strong and weak ties to small business growth

The Evolving Role of Supply Chain Managers in global Channels of Distribution and Logistics Systems

Cataloged from PDF version of article.Purpose – Supply chains have become a strategic strength to many firms due to the nature of the globalization of business. The past roles of supply chain managers have changed dramatically and now also include various new duties that will enhance firm competitiveness due to their boundary spanning nature and the new focus of learning organizations. The paper aims to discuss these issues. Design/methodology/approach – This was a theoretically developed paper exploring trust, learning organizations, and supply chains. Findings – Researchers are now focussing on the relationship among the supply chain network through the paradigm of relational marketing as the governance structures of contractual arrangements globally cannot be anticipated. Originality/value – The research through the lens of relational marketing explores how supply chain managers’ core duties are now compounded by global/cultural nuances in respect to implicit knowledge acquisition and relationship development through strong-form trust

Phase separation in a boson-fermion mixture of Lithium atoms

We use a semiclassical three-fluid model to analyze the conditions for spatial phase separation in a mixture of fermionic Li-6 and a (stable) Bose-Einstein condensate of Li-7 atoms under cylindrical harmonic confinement, both at zero and finite temperature. We show that with the parameters of the Paris experiment [F. Schrek et al., Phys. Rev. Lett. 87 080403 (2001)] an increase of the boson-fermion scattering length by a factor five would be sufficient to enter the phase-separated regime. We give examples of configurations for the density profiles in phase separation and estimate that the transition should persist at temperatures typical of current experiments. For higher values of the boson-fermion coupling we also find a new phase separation between the fermions and the bosonic thermal cloud at finite temperature.Comment: 8 pages, 4 figures, new version of Fig. 4 and typos correcte

Transmittivity of a Bose-Einstein condensate on a lattice: interference from period doubling and the effect of disorder

We evaluate the particle current flowing in steady state through a Bose-Einstein condensate subject to a constant force in a quasi-onedimensional lattice and to attractive interactions from fermionic atoms that are localized in various configurations inside the lattice wells. The system is treated within a Bose-Hubbard tight binding model by an out-of-equilibrium Green's function approach. A new band gap opens up when the lattice period is doubled by locating the fermions in alternate wells and yields an interference pattern in the transmittivity on varying the intensity of the driving force. The positions of the transmittivity minima are determined by matching the period of Bloch oscillations and the time for tunnelling across the band gap. Massive disorder in the distribution of the fermions will wash out the interference pattern, but the same period doubling of the lattice can be experimentally realized in a four-beam set-up. We report illustrative numerical results for a mixture of 87Rb and 40K atoms in an optical lattice created by laser beams with a wavelength of 763 nm.Comment: 13 pages, 5 figure

Demixing in mesoscopic boson-fermion clouds inside cylindrical harmonic traps: quantum phase diagram and role of temperature

We use a semiclassical three-fluid thermodynamic model to evaluate the phenomena of spatial demixing in mesoscopic clouds of fermionic and bosonic atoms at high dilution under harmonic confinement, assuming repulsive boson-boson and boson-fermion interactions and including account of a bosonic thermal cloud at finite temperature T. The finite system size allows three different regimes for the equilibrium density profiles at T=0: a fully mixed state, a partially mixed state in which the overlap between the boson and fermion clouds is decreasing, and a fully demixed state where the two clouds have zero overlap. We propose simple analytical rules for the two cross-overs between the three regimes as functions of the physical system parameters and support these rules by extensive numerical calculations. A universal ``phase diagram'' expressed in terms of simple scaling parameters is shown to be valid for the transition to the regime of full demixing, inside which we identify several exotic configurations for the two phase-separated clouds in addition to simple ones consisting of a core of bosons enveloped by fermions and "vice versa". With increasing temperature the main role of the growing thermal cloud of bosons is to transform some exotic configurations into more symmetric ones, until demixing is ultimately lost. For very high values of boson-fermion repulsive coupling we also report demixing between the fermions and the thermally excited bosons.Comment: 11 pages, 8 figure

From 16th Century to 21th Century Sheik Yahya Efendi Lodge Complex

Tasavvuf düşüncesi ile birlikte gelişen tarikatlara zamanla duyulan ihtiyaç sonucu tekkeler (tarikat yapıları) ortaya çıkmıştır. Özellikle Osmanlı Devleti’nin kuruluş döneminde toplumun çeşitli ihtiyaçlarını karşılamak üzere ortaya çıkan ve devletin gelişiminde oldukça etkili olan tekke ve tarikatlar, Cumhuriyet Dönemine gelindiğinde işlevsel görevlerini yitirdikleri düşüncesiyle kaldırılmışlardır. Osmanlı Döneminde önemli değişiklikler geçirerek Cumhuriyet Dönemine ulaşan çoğu tekkelerin kapatılması neticesinde bu yapılardan bazıları yok olmuş, bazıları onarılarak ve köklü değişiklikler geçirerek günümüze ulaşmıştır. Günümüzde cami olarak kullanılan Şeyh Yahya Efendi Tevhidhanesi’nin bir parçası olduğu Şeyh Yahya Efendi Külliyesi’nin (Tekkesi’nin) kuruluşundan bugüne kadar geçirdiği fiziksel değişiklikler ve tarihsel süreç, eldeki veriler elverdiği ölçüde incelenerek ortaya konmaya çalışılmıştır. Yazılı ve görsel malzemelerden (eski-yeni fotoğraf ve rölövelerden) yararlanılarak külliye yapılarının geçirmiş olduğu değişiklikler yanında günümüzdeki mimari durumları ele alınarak tanımlanmıştır.With the development of Islamic sufism, dervish orders increased in time. Eventually with the need of space for social activities, the dervish lodges and complexes emerged. In the Ottoman time, dervish lodges were very effective establishments. During the constitution of the Turkish Republic, these lodges which had become degenerated were closed. In time, some of the buildings demolished, others have undergone restorations and were partially preserved. Sheik Yahya Efendi Lodge Complex at issue, is studied with a historical aspect, the building complex is tried to be defined by the use of scarce archive records and survey drawings