Tavis-Cummings models and their quasi-exactly solvable Schrödinger Hamiltonians

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Ultracold quantum gases in triangular optical lattices

Over the last years the exciting developments in the field of ultracold atoms confined in optical lattices have led to numerous theoretical proposals devoted to the quantum simulation of problems e.g. known from condensed matter physics. Many of those ideas demand for experimental environments with non-cubic lattice geometries. In this paper we report on the implementation of a versatile three-beam lattice allowing for the generation of triangular as well as hexagonal optical lattices. As an important step the superfluid-Mott insulator (SF-MI) quantum phase transition has been observed and investigated in detail in this lattice geometry for the first time. In addition to this we study the physics of spinor Bose-Einstein condensates (BEC) in the presence of the triangular optical lattice potential, especially spin changing dynamics across the SF-MI transition. Our results suggest that below the SF-MI phase transition, a well-established mean-field model describes the observed data when renormalizing the spin-dependent interaction. Interestingly this opens new perspectives for a lattice driven tuning of a spin dynamics resonance occurring through the interplay of quadratic Zeeman effect and spin-dependent interaction. We finally discuss further lattice configurations which can be realized with our setup.Comment: 19 pages, 7 figure

Comparison of the arrhythmogenicity of acepromazine, xylazine and their combination in pentobarbital-anesthetized rats

Preanesthetic medications are often used in combination with injectable anesthetics in a variety of laboratory animal species. Simultaneous administration of sedative drugs, such as alpha2-adrenergic agonists and phenothiazines, provides muscle relaxation and reduces induction doses of anesthetic agents. However, these drugs may have significant cardiovascular and arrythmogenic effects which may contribute to anesthetic morbidity and mortality (Dyson et al., 1998).Results of previous reports indicate that xylazine, an alpha2-adrenergic agonist, may sensitize the myocardium to epinephrine in dogs anesthetized with halothane (Muir et al., 1975; Tranquilli et al., 1986), isoflurane (Tranquilli et al., 1988) and ketamine (Wright et al., 1987); whereas, acepromazine, a phenothiazine tranquilizer, possessed a protective action against catecholamine-induced arrhythmia in dogs anesthetized with halothane (Muir et al., 1975; Dyson & Pettifer, 1997). The male rat has been used as an animal model to determine the arrhythmic doses of epinephrine during halothane and isoflurane anesthesia (Laster et al., 1990). Rats are commonly used for scientific research and may be anesthetized using injectable or inhalant anesthetic agents for a variety of surgical procedures (Flecknell, 2009); however, injectable anesthetics are commonly preferred in a laboratory setting.Pentobarbital, as a short acting barbiturate anesthetic, is used for short surgical procedures in rats. It is rapidly absorbed following intraperitoneal administration and provide anesthesia for up to 60 min in the rat (Flecknell, 2009).The purpose of this study was to evaluate the effects of clinical doses of acepromazine, xylazine and their combination on the occurrence of epinephrine induced arrhythmia in rats under pentobarbital anesthesia

SURVEY THE MUTATION OF FGB (BETA FIBRINOGEN) AND FV (FACTOR V LEIDEN), FACTOR XIII AND FACTOR II (PROTHROMBIN), IN PATIENTS WITH RECURRENT ABORTIONS ALONG WITH NORMAL KARYOTYPE

Some pregnancies are abnormal in human genetically and end with the spontaneous abortion, which is the most common problem of pregnancy. The recurrent abortions are often referred to as multifactorial disease that one of which is thrombosis. The thrombosis in placenta capillaries seems to disturb the blood circulation between the mother and the fetus and eventually lead to abortion. Recently, studies have shown that genetic basis for thrombophilia relates with recurrent abortion. The aim of this study is the survey of G1691A and G4070A mutations in the Factor V gene, -455G>A mutation in the gen of XIII factor, G103T mutation in Beta fibrinogen and A20210G mutation in the thrombin gene. The samples were collected from 60 patients referred to Tehran Imam Khomeini hospital .DNA was extracted from patients' blood samples by multiple PCR simultaneously containing different mutations were duplicated then the existence of mutation was evaluated by the strip technique. The genes mutation of G1691A in Factor V, G4070A in Factor V, G103T in Beta fibrinogen, -455G>A in the XIII factor and G20210A were identified 6.6, 45, 36, 40 and 3.3 respectively. Studies on the other population showed that frequency of examined mutations varies with other communities. Anyway, more samples are required in order to obtain more accurate statistics related to the frequency of mutations

Genome-wide analysis of alternative splicing events in Hordeum vulgare: highlighting retention of intron-based splicing and its possible function through network analysis

In this study, using homology mapping of assembled expressed sequence tags against the genomic data, we identified alternative splicing events in barley. Results demonstrated that intron retention is frequently associated with specific abiotic stresses. Network analysis resulted in discovery of some specific sub-networks between miRNAs and transcription factors in genes with high number of alternative splicing, such as cross talk between SPL2, SPL10 and SPL11 regulated by miR156 and miR157 families. To confirm the alternative splicing events, elongation factor protein (MLOC_3412) was selected followed by experimental verification of the predicted splice variants by Semi quantitative Reverse Transcription PCR (qRT-PCR). Our novel integrative approach opens a new avenue for functional annotation of alternative splicing through regulatory-based network discovery.Bahman Panahi, Seyed Abolghasem Mohammadi, Reyhaneh Ebrahimi Khaksefidi, Jalil Fallah Mehrabadi, Esmaeil Ebrahimi

Marshall syndrome in children referred to specialist clinic of Imam Khomeini Hospital of Ilam, Iran, 2012

Periodic fever syndrome is a self-inflammatory disease. Since the disease is benign and self-limiting, the present study aimed to achieve a model to detect and differentiate it from other infectious diseases .In this study all children residing in Ilam who were suspected of Marshall Syndrome were examined. We chose a sample comprising children referred to Imam Hospital clinic of Ilam in 2012. Inclusion criteria consisted of more than three periods of fever without a source of infection, fever periods shorter than 5 days and repeated at intervals of about one month. The collected data were analyzed using SPSS software 16. We used both of descriptive and inferential statistics, Kolmogrov smirnov, Chi-square. Significance level of P ≤ 0.05 was considered. The average of patients' age was 4.9 ± 1.8 months and their gender perception was 85.7 male and 14.3 female. In this study the average age of symptoms emergence was 48.33 ± 23.25 month. The average of fever periods in surveyed patients was 4.09 ± 0.88 days (minimum 3 days & maximum 5 days) and the intervals between fever periods was 40.23 ± 16.84 in average. The applied treatments in this study were Prednisolone and Ttonsillectomy. There was significant relationship between age and the symptoms (P<0.007). By having a true perception of Marshall Syndrome using diagnosis criteria, we could prevent uncontrolled prescription of antibiotics and their possible side effects, and it is a positive step towards reducing healthcare costs

Quantum simulation of frustrated magnetism in triangular optical lattices

Magnetism plays a key role in modern technology as essential building block of many devices used in daily life. Rich future prospects connected to spintronics, next generation storage devices or superconductivity make it a highly dynamical field of research. Despite those ongoing efforts, the many-body dynamics of complex magnetism is far from being well understood on a fundamental level. Especially the study of geometrically frustrated configurations is challenging both theoretically and experimentally. Here we present the first realization of a large scale quantum simulator for magnetism including frustration. We use the motional degrees of freedom of atoms to comprehensively simulate a magnetic system in a triangular lattice. Via a specific modulation of the optical lattice, we can tune the couplings in different directions independently, even from ferromagnetic to antiferromagnetic. A major advantage of our approach is that standard Bose-Einstein-condensate temperatures are sufficient to observe magnetic phenomena like N\'eel order and spin frustration. We are able to study a very rich phase diagram and even to observe spontaneous symmetry breaking caused by frustration. In addition, the quantum states realized in our spin simulator are yet unobserved superfluid phases with non-trivial long-range order and staggered circulating plaquette currents, which break time reversal symmetry. These findings open the route towards highly debated phases like spin-liquids and the study of the dynamics of quantum phase transitions.Comment: 5 pages, 4 figure

Topological orbital ladders

We unveil a topological phase of interacting fermions on a two-leg ladder of unequal parity orbitals, derived from the experimentally realized double-well lattices by dimension reduction. $Z_2$ topological invariant originates simply from the staggered phases of $sp$-orbital quantum tunneling, requiring none of the previously known mechanisms such as spin-orbit coupling or artificial gauge field. Another unique feature is that upon crossing over to two dimensions with coupled ladders, the edge modes from each ladder form a parity-protected flat band at zero energy, opening the route to strongly correlated states controlled by interactions. Experimental signatures are found in density correlations and phase transitions to trivial band and Mott insulators.Comment: 12 pages, 5 figures, Revised title, abstract, and the discussion on Majorana numbe