XY Systems' project management office
Hayley, David
2005-01-01
XY Systems' (XY) competitive advantage stems from reputation and an ability to build long-term relationships. Both XY and its clients benefit from their long-standing relationships. The technology industry is highly competitive and competitors will use every opportunity to tarnish XY's reputation. Recently, XY's clients expressed dissatisfaction at XY's lack of Project Management (PM) skills. In addition, XY's management cannot understand the status of all XY's projects because of XY's rapid ...
Observation of the ground-state geometric phase in a Heisenberg XY model.
Peng, Xinhua; Wu, Sanfeng; Li, Jun; Suter, Dieter; Du, Jiangfeng
2010-12-10
Geometric phases play a central role in a variety of quantum phenomena, especially in condensed matter physics. Recently, it was shown that this fundamental concept exhibits a connection to quantum phase transitions where the system undergoes a qualitative change in the ground state when a control parameter in its Hamiltonian is varied. Here we report the first experimental study using the geometric phase as a topological test of quantum transitions of the ground state in a Heisenberg XY spin model. Using NMR interferometry, we measure the geometric phase for different adiabatic circuits that do not pass through points of degeneracy.
Classical ground states of symmetric Heisenberg spin systems
Schmidt, H J
2003-01-01
We investigate the ground states of classical Heisenberg spin systems which have point group symmetry. Examples are the regular polygons (spin rings) and the seven quasi-regular polyhedra including the five Platonic solids. For these examples, ground states with special properties, e.g. coplanarity or symmetry, can be completely enumerated using group-theoretical methods. For systems having coplanar (anti-) ground states with vanishing total spin we also calculate the smallest and largest energies of all states having a given total spin S. We find that these extremal energies depend quadratically on S and prove that, under certain assumptions, this happens only for systems with coplanar S = 0 ground states. For general systems the corresponding parabolas represent lower and upper bounds for the energy values. This provides strong support and clarifies the conditions for the so-called rotational band structure hypothesis which has been numerically established for many quantum spin systems.
Spectroscopic observations of the RS CVn-type binary systems SV Cam and XY UMa
Rainger, P. P.; Hilditch, R. W.; Edwin, R. P.
1991-01-01
Radial velocities of the primary components of the two RS CVn-type binary systems SV Cam and XY UMa are presented, for the first time for XY UMa. Neither secondary component could be detected. A change of 5.0 + or - 13 km/sec in the systemic velocity of SV Cam is found over 40 years, which lends some support to the current model of SV Cam being a triple system. If the masses of the G3 V primary components of both systems are assumed to be 1 solar mass, then the secondaries are 0.7 (SV Cam) and 0.6 (XY UMa) solar masses; all four stars are main sequence objects with SV Cam being rather more evolved than XY UMa.
Spectroscopic observations of the RS CVn-type binary systems SV Cam and XY UMa
Energy Technology Data Exchange (ETDEWEB)
Rainger, P.P.; Hilditch, R.W.; Edwin, R.P. (Saint Andrews Univ. (UK). Observatory)
1991-01-01
Radial velocities of the primary components of the two RS CVn-type binary systems SV Cam and XY UMa are presented, for the first time for XY UMa. Neither secondary component could be detected. A change of 5.0+-1.3km s{sup -1} in the systemic velocity of SV Cam is found over 40 years which lends some support to the current model of SV Cam being a triple system. If the masses of the G3 V primary components of both systems are assumed to be one solar mass, then the secondaries are 0.7 (SV CAM) and 0.6 (XY UMa) solar masses; all four stars are main sequence objects with SV Cam being rather more evolved than XY UMa. (author).
Weyl-Heisenberg frames, translation invariant systems, and the Walnut representation
DEFF Research Database (Denmark)
Casazza, P.G.; Christensen, Ole; Janssen, A. J. E. M.
2001-01-01
We present a comprehensive analysis of the convergence properties of the frame operators of Weyl-Heisenberg systems and shift-invariant systems, and relate these to the convergence of the Walnut representation. We give a deep analysis of necessary conditions and sufficient conditions for converge...
Entanglement Dynamics in Heisenberg spin systems coupled to a dissipative environment
Sadiek, Gehad; Almalki, Samaher
Heisenberg Spin chains and lattices have been intensively used to represent many of the physical systems that are considered as promising candidates for quantum computing and quantum information processing. The main obstacle toward realizing the ultimate goals in these fields is decoherence caused by the surrounding dissipative and thermal environments. We are studying spin relaxation and entanglement dynamics in one and two-dimensional XYZ Heisenberg spin systems under coupling with a dissipative Lindblad environment at finite temperature. We investigate the effect of the anisotropy of the coupling between the spins on the asymptotic steady state of the system and the spin relaxation rates at different temperatures of the environment. We demonstrate the role played by the initial system setup on the entanglement and spin dynamics and steady state properties. Also we examine the effect of the long range interaction between the spins on the asymptotic behavior of the system.
XX/XY system of sex determination in the geophilomorph centipede Strigamia maritima
Czech Academy of Sciences Publication Activity Database
Green, J. E.; Dalíková, Martina; Sahara, K.; Marec, František; Akam, M.
2016-01-01
Roč. 11, č. 2 (2016), č. článku e0150292. E-ISSN 1932-6203 R&D Projects: GA AV ČR IAA600960925; GA ČR(CZ) GA14-22765S Institutional support: RVO:60077344 Keywords : sex determination * Strigamia maritima * XX/XY system Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.806, year: 2016 http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0150292
Infrared photometry of the RS CVn short-period systems - XY UMa and WY Cnc
Energy Technology Data Exchange (ETDEWEB)
Arevalo, M.J.; Lazaro, C. (Instituto de Astrofisica de Canarias, La Laguna (Spain))
1990-03-01
Infrared J and K light curves of two RS CVn short-period systems, XY UMa and WY Cnc, are presented. Both systems show similar variability in the infrared to that observed in the visual. From the colors an infrared excess is inferred for the primary component of both systems. A new determination of their geometrical elements is presented and the resulting parameters are compared to those previously obtained from visible photometry. The light curves show peculiarities that may indicate the presence of gas streams in the systems. 27 refs.
A Newly Developed X-Y Planar Nano-Motion Table System with Large Travel Ranges
Kurisaki, Yugo; Sawano, Hiroshi; Yoshioka, Hayato; Shinno, Hidenori
Precision motion control technology has been widely used in high accuracy applications such as advanced scientific instruments and semiconductor fabrication equipment. In particular, the nano-motion control system with multiple degrees of freedom positioning in large travel ranges has been required in the field of precision engineering. In order to realize such a system, it is necessary and indispensable to develop a planar motion table system based on a new design concept. This paper presents a newly developed X-Y planar nano-motion table system with large travel ranges. This system is composed of a fine motion table and a coarse motion mechanism. The fine motion table is supported by porous aerostatic bearings and driven by voice coil motors with a laser interferometer feedback in a perfect non-contact condition. In addition, the table is driven at the center of gravity during the X-Y planar motion. The coarse motion mechanism has the frame structure with the coils of voice coil motors for the fine motion table. In order to enlarge the table travel ranges, the coarse motion mechanism follows the fine table motion. Performance evaluation results confirm that the developed table system has a remarkable performance which includes nanometer positioning capability over large travel ranges.
XX/XY System of Sex Determination in the Geophilomorph Centipede Strigamia maritima.
Directory of Open Access Journals (Sweden)
Jack E Green
Full Text Available We show that the geophilomorph centipede Strigamia maritima possesses an XX/XY system of sex chromosomes, with males being the heterogametic sex. This is, to our knowledge, the first report of sex chromosomes in any geophilomorph centipede. Using the recently assembled Strigamia genome sequence, we identified a set of scaffolds differentially represented in male and female DNA sequence. Using quantitative real-time PCR, we confirmed that three candidate X chromosome-derived scaffolds are present at approximately twice the copy number in females as in males. Furthermore, we confirmed that six candidate Y chromosome-derived scaffolds contain male-specific sequences. Finally, using this molecular information, we designed an X chromosome-specific DNA probe and performed fluorescent in situ hybridization against mitotic and meiotic chromosome spreads to identify the Strigamia XY sex-chromosome pair cytologically. We found that the X and Y chromosomes are recognizably different in size during the early pachytene stage of meiosis, and exhibit incomplete and delayed pairing.
Bidau, C J; Marti, D A
2000-01-01
The origin of neo-XY sex systems in Acrididae is usually explained through an X-autosome centric fusion, and the behaviour of the neo-sex chromosomes has been solely studied in males. In this paper we analysed male and female Dichroplus vittatus. The karyotype comprises 2n = 20 chromosomes including 9 pairs of autosomes and a sex chromosome pair that includes a large metacentric neo-X and a small telocentric neo-Y. We compared the meiotic behaviour of the sex bivalent between both sexes. Mean cell autosomal chiasma frequency was low in both sexes and slightly but significantly higher in males than in females. Chiasma frequency of females increased significantly when the sex-bivalent was included. Chiasma distribution was basically distal in both sexes. Behaviour of the neo-XY pair is complex as a priori suggested by its structure, which was analysed in mitosis and meiosis of diploid and polyploid cells. During meiosis, orientation of the neo-XY is highly irregular; only 21% of the metaphase I spermatocytes show standard orientation. In the rest of cells, the alternate or simultaneous activity of an extra kinetochore in the distal end of the short arm (XL) of the neo-X, determined unusual MI orientations and a high frequency of non-disjunction and lagging of the sex-chromosomes. In females, the neo-XX bivalent had a more regular behaviour but showed 17% asynapsis in the XL arm which, in those cases orientated its distal ends towards opposite spindle poles suggesting, again, the activity of a second kinetochore. The dicentric nature and the unstable meiotic behaviour of the sex neo-chromosomes of D. vittatus suggest a recent origin of the sex determination mechanism, with presumable adaptive advantages which could compensate their potential negative heterosis. Our observations suggest that the origin of the neo-sex system was a tandem fusion of two original telocentric X-chromosomes followed by another tandem fusion with the small megameric bivalent and a further
Realizing the classical XY Hamiltonian in polariton simulators
Berloff, Natalia G.; Silva, Matteo; Kalinin, Kirill; Askitopoulos, Alexis; Töpfer, Julian D.; Cilibrizzi, Pasquale; Langbein, Wolfgang; Lagoudakis, Pavlos G.
2017-11-01
The vast majority of real-life optimization problems with a large number of degrees of freedom are intractable by classical computers, since their complexity grows exponentially fast with the number of variables. Many of these problems can be mapped into classical spin models, such as the Ising, the XY or the Heisenberg models, so that optimization problems are reduced to finding the global minimum of spin models. Here, we propose and investigate the potential of polariton graphs as an efficient analogue simulator for finding the global minimum of the XY model. By imprinting polariton condensate lattices of bespoke geometries we show that we can engineer various coupling strengths between the lattice sites and read out the result of the global minimization through the relative phases. Besides solving optimization problems, polariton graphs can simulate a large variety of systems undergoing the U(1) symmetry-breaking transition. We realize various magnetic phases, such as ferromagnetic, anti-ferromagnetic, and frustrated spin configurations on a linear chain, the unit cells of square and triangular lattices, a disordered graph, and demonstrate the potential for size scalability on an extended square lattice of 45 coherently coupled polariton condensates. Our results provide a route to study unconventional superfluids, spin liquids, Berezinskii-Kosterlitz-Thouless phase transition, and classical magnetism, among the many systems that are described by the XY Hamiltonian.
Weingartner, Laura A; Moore, Richard C
2012-12-01
The sex chromosomes of the tropical crop papaya (Carica papaya) are evolutionarily young and consequently allow for the examination of evolutionary mechanisms that drive early sex chromosome divergence. We conducted a molecular population genetic analysis of four X/Y gene pairs from a collection of 45 wild papaya accessions. These population genetic analyses reveal striking differences in the patterns of polymorphism between the X and Y chromosomes that distinguish them from other sex chromosome systems. In most sex chromosome systems, the Y chromosome displays significantly reduced polymorphism levels, whereas the X chromosome maintains a level of polymorphism that is comparable to autosomal loci. However, the four papaya sex-linked loci that we examined display diversity patterns that are opposite this trend: the papaya X alleles exhibit significantly reduced polymorphism levels, whereas the papaya Y alleles maintain greater than expected levels of diversity. Our analyses suggest that selective sweeps in the regions of the X have contributed to this pattern while also revealing geographically restricted haplogroups on the Y. We discuss the possible role sexual selection and/or genomic conflict have played in shaping the contrasting patterns of polymorphism found for the papaya X and Y chromosomes.
DEFF Research Database (Denmark)
Bhaskar, Mahajan Sagar; Sanjeevikumar, Padmanaban; Wheeler, Patrick
2016-01-01
A New breed of a buck boost converter, named as the XY converter family is proposed in this article. In the XY family, 16 topologies are presented which are highly suitable for renewable energy applications which require a high ratio of DC-DC converter; such as a photovoltaic multilevel inverter...... system, high voltage automotive applications and industrial drives. Compared to the traditional boost converter and existing recent converters, the proposed XY converter family has the ability to provide a higher output voltage by using less number of power devices and reactive components. Other distinct...... features of the XY converter family are i) Single control switch ii) Provide negative output voltage iii) Non-isolated topologies iv) High conversion ratio without making the use of high duty cycle and v) modular structure. XY family is compared with the recent high step-up converters and the detailed...
Jetybayev, Ilyas Yerkinovich; Bugrov, Alexander Gennadievich; Ünal, Mustafa; Buleu, Olesya Georgievna; Rubtsov, Nikolay Borisovich
2017-02-07
Neo-XY sex chromosome determination is a rare event in short horned grasshoppers, but it appears with unusual frequency in the Pamphagidae family. The neo-Y chromosomes found in several species appear to have undergone heterochromatinization and degradation, but this subject needs to be analyzed in other Pamphagidae species. We perform here karyotyping and molecular cytogenetic analyses in 12 Pamphagidae species from the center of biodiversity of this group in the previously-unstudied Anatolian plateau. The basal karyotype for the Pamphagidae family, consisting of 18 acrocentric autosomes and an acrocentric X chromosome (2n♂ = 19, X0; 2n♀ = 20, XX), was found only in G. adaliae. The karyotype of all other studied species consisted of 16 acrocentric autosomes and a neo-XY sex chromosome system (2n♂♀ = 18, neo-XX♀/neo-XY♂). Two different types of neo-Y chromosomes were found. One of them was typical for three species of the Glyphotmethis genus, and showed a neo-Y chromosome being similar in size to the XR arm of the neo-X, with the addition of two small subproximal interstitial C-blocks. The second type of the neo-Y chromosome was smaller and more heterochromatinized than the XR arm, and was typical for all Nocarodeini species studied. The chromosome distribution of C-positive regions and clusters of ribosomal DNA (rDNA) and telomeric repeats yielded additional information on evolution of these neo-XY systems. Most Pamphagidae species in the Anatolian region were found to have neo-XY sex chromosome systems, belonging to two different evolutionary lineages, marked by independent X-autosome fusion events occurred within the Trinchinae and Pamphaginae subfamilies. The high density of species carrying neo-XY systems in the Anatolian region, and the different evolutionary stage for the two lineages found, one being older than the other, indicates that this region has a long history of neo-XY sex chromosome formation.
Panuzzo, P.; Li, J.; Caux, E.
2012-09-01
The Herschel Interactive Processing Environment (HIPE) was developed by the European Space Agency (ESA) in collaboration with NASA and the Herschel Instrument Control Centres, to provide the astronomical community a complete environment to process and analyze the data gathered by the Herschel Space Observatory. One of the most important components of HIPE is the plotting system (named PlotXY) that we present here. With PlotXY it is possible to produce easily high quality publication-ready 2D plots. It provides a long list of features, with fully configurable components, and interactive zooming. The entire code of HIPE is written in Java and is open source released under the GNU Lesser General Public License version 3. A new version of PlotXY is being developed to be independent from the HIPE code base; it is available to the software development community for the inclusion in other projects at the URL google.com/p/jplot2d/'>http://code.google.com/p/jplot2d/.
Indian Academy of Sciences (India)
Heisenberg's contributions to the understanding of ferromagnetism are reviewed. The special fea- tures of ferrolnagnetism, vis-a-vis dia and para magnetism, are introduced and the necessity of a Weiss molecular field is explained. It is shown how Heisenberg identified the quantum mechan- ical exchange interaction, which ...
DEFF Research Database (Denmark)
Albrechtslund, Anne-Mette Bech; Albrechtslund, Anders
In this paper we trace the development of an epistemic culture as portrayed in Breaking Bad (2008-2013). The acclaimed TV series was aired on the AMC network and later released on Netflix to become the “most binge-watched show” (Abrams, 2014) when all seasons were available to stream. Much...... procedures, such as blind peer-review (meth users judge the quality of the product and determine its value), reputation and status (Walter cleverly manages his reputation by branding himself as “Heisenberg”), and a system of obligatory passage points. Our paper explores this serialized enactment of science...
Entanglement Teleportation Through 1D Heisenberg Chain
Hao, X; Zhu, S
2005-01-01
Information transmission of two qubits through two independent 1D Heisenberg chains as a quantum channel is analyzed. It is found that the entanglement of two spin-$\\frac 12$ quantum systems is decreased during teleportation via the thermal mixed state in 1D Heisenberg chain. The entanglement teleportation will be realized if the minimal entanglement of the thermal mixed state is provided in such quantum channel. High average fidelity of teleportation with values larger than 2/3 is obtained w...
Directory of Open Access Journals (Sweden)
Mikhail G Divashuk
Full Text Available Hemp (Cannabis sativa L. was karyotyped using by DAPI/C-banding staining to provide chromosome measurements, and by fluorescence in situ hybridization with probes for 45 rDNA (pTa71, 5S rDNA (pCT4.2, a subtelomeric repeat (CS-1 and the Arabidopsis telomere probes. The karyotype has 18 autosomes plus a sex chromosome pair (XX in female and XY in male plants. The autosomes are difficult to distinguish morphologically, but three pairs could be distinguished using the probes. The Y chromosome is larger than the autosomes, and carries a fully heterochromatic DAPI positive arm and CS-1 repeats only on the less intensely DAPI-stained, euchromatic arm. The X is the largest chromosome of all, and carries CS-1 subtelomeric repeats on both arms. The meiotic configuration of the sex bivalent locates a pseudoautosomal region of the Y chromosome at the end of the euchromatic CS-1-carrying arm. Our molecular cytogenetic study of the C. sativa sex chromosomes is a starting point for helping to make C. sativa a promising model to study sex chromosome evolution.
Biconical structures in two-dimensional anisotropic Heisenberg antiferromagnets
Holtschneider, M.; Selke, W.
2007-01-01
Square lattice Heisenberg and XY antiferromagnets with uniaxial anisotropy in a field along the easy axis are studied. Based on ground state considerations and Monte Carlo simulations, the role of biconical structures in the transition region between the antiferromagnetic and spin--flop phases is analyzed. In particular, adding a single--ion anisotropy to the XXZ antiferromagnet, one observes, depending on the sign of that anisotropy, either an intervening biconical phase or a direct transiti...
Roberti, Joseph V.
1979-01-01
A process for eliminating the xy term in a quadratic equation in two variables is presented. The author feels this process will be within the reach of more high school students than more commonly used methods. (MK)
Ground State of the One Dimensional Heisenberg Model with NNN Interactions
Mancini, J. D.; Fessatidis, V.; Bowen, S. P.; Maly, J.; Murawski, R. K.
A great number of insights into a variety of complex physical many-body systems have been gleaned from the study of the of the one-dimensional Heisenberg model. There exists a number of quasi one-dimensional inorganic compounds such as TTF - CUS4C4(CF3) 4 , SRCU2O3 , VO2P2O7 and CuGeO3 for which this Hamiltonian system is relevant. For this work we shall study the one-dimensional Heisenberg Model with nearest, next nearest and next -next nearest interactions. The Hamiltonian is given by: H =J1 ∑ ksk .sk + 1 +J2 ∑ ksk .sk + 2 +J3 ∑ ksk .sk + 3 where sk represents the spin 1 / 2 operator along a chain of N sites and periodic boundary conditions is assumed for the closed chain. We note that it is further possible to describe the Coulomb interaction subject to the Pauli exclusion principle for two quantum dots an XY model. Here we shall study the ground-state energy as well as the energy gap of this system using both a Lanczos (tridiagonal) scheme as well as a generalized Moments approach.
Indian Academy of Sciences (India)
Page 1. CPMG/KAlBGE-340/2003-05. Licenced to post WPP No.6. Resonance - August 2004. Wernel· Heisenberg. (1901 - 1976). Registered with Registrar of Newspapers in India vide Regn. No. 66273/96. ISSN 0971-8044.
Indian Academy of Sciences (India)
Home; Fellowship. Fellow Profile. Elected: 1935 Honorary. Heisenberg, Prof. Werner Karl Nobel Laureate (Physics) - 1932. Date of birth: 5 December 1901. Date of death: 1 February 1976. YouTube; Twitter; Facebook; Blog. Academy News. IAS Logo. Theory Of Evolution. Posted on 23 January 2018. Joint Statement by the ...
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 9; Issue 8. Heisenberg and Ferromagnetism. S Chatterjee. General Article Volume 9 Issue 8 August 2004 pp 57-66. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/009/08/0057-0066. Keywords.
X-ray excited optical luminescence studies on the system BaXY (X ...
Indian Academy of Sciences (India)
The present paper reports the experimental observations on the x-ray excited optical luminescence (XEOL) along with the afterglow and colour center features found for the barium salts, represented by the formula, Ba, where and are the halides. The system thus consists of four dihalides (BaF2, . . . ,BaI2) and six ...
Vawter, G. Allen; Hadley, G. Ronald
1997-01-01
An integrated optical XY coupler having two converging input waveguide arms meeting in a central section and a central output waveguide arm and two diverging flanking output waveguide arms emanating from the central section. In-phase light from the input arms constructively interfers in the central section to produce a single mode output in the central output arm with the rest of the light being collected in the flanking output arms. Crosstalk between devices on a substrate is minimized by this collection of the out-of-phase light by the flanking output arms of the XY coupler.
Heerens, W.C.; Laham, C.D.; Holman, A.E.
1997-01-01
An XY-displacement device (1) with a four-fold symmetry comprises a reference frame (10); an object mount (20) for holding an object (22) to be displaced; an X-manipulator (100) coupled between the reference frame (10) and the object mount (20), which provides a rigid coupling between the object
Jung, Eun Jung; Im, Do Hwa; Park, Yong Hee; Byun, Jung Mi; Kim, Young Nam; Jeong, Dae Hoon; Sung, Moon Su; Kim, Ki Tae; An, Hyo Jung; Jung, Soo Jin; Lee, Kyung Bok
2017-07-01
Disorders of sex development (DSD) are congenital conditions characterized by atypical development of chromosomal, gonadal, and phenotypic sex. 46, XY DSD can result from disorders of testicular development or disorders of androgen synthesis/action. Prophylactic gonadectomy should be considered in patients with 46, XY DSD because of the increased risk of gonadal malignancy. We report two rare cases of 46, XY DSD, including XY pure gonadal dysgenesis and complete androgen insensitivity syndrome, who underwent a prophylactic gonadectomy.
Magnetic properties of a classical XY spin dimer in a “planar” magnetic field
Energy Technology Data Exchange (ETDEWEB)
Ciftja, Orion, E-mail: ogciftja@pvamu.edu [Department of Physics, Prairie View A& M University, Prairie View, TX 77446 (United States); Prenga, Dode [Department of Physics, Faculty of Natural Sciences, University of Tirana, Bul. Zog I, Tirana (Albania)
2016-10-15
Single-molecule magnetism originates from the strong intra-molecular magnetic coupling of a small number of interacting spins. Such spins generally interact very weakly with the neighboring spins in the other molecules of the compound, therefore, inter-molecular spin couplings are negligible. In certain cases the number of magnetically coupled spins is as small as a dimer, a system that can be considered the smallest nanomagnet capable of storing non-trivial magnetic information on the molecular level. Additional interesting patterns arise if the spin motion is confined to a two-dimensional space. In such a scenario, clusters consisting of spins with large-spin values are particularly attractive since their magnetic interactions can be described well in terms of classical Heisenberg XY spins. In this work we calculate exactly the magnetic properties of a nanomagnetic dimer of classical XY spins in a “planar” external magnetic field. The problem is solved by employing a mathematical approach whose idea is the introduction of auxiliary spin variables into the starting expression of the partition function. Results for the total internal energy, total magnetic moment, spin–spin correlation function and zero-field magnetic susceptibility can serve as a basis to understand the magnetic properties of large-spin dimer building blocks. - Highlights: • Exact magnetic properties of a dimer system of classical XY spins in magnetic field. • Partition function in nonzero magnetic field obtained in closed-form. • Novel exact analytic results are important for spin models in a magnetic field. • Result provides benchmarks to gauge the accuracy of computational techniques.
Viana, Patrik F; Ezaz, Tariq; Marajó, Leandro; Ferreira, Milena; Zuanon, Jansen; Cioffi, Marcelo B; Bertollo, Luiz A C; Gross, Maria C; Feldberg, Eliana
2017-01-01
The genus Colomesus is the sole representative of the family Tetraodontidae in the Amazon region. Here, Colomesus asellus was analyzed using conventional and molecular cytogenetic protocols. Its diploid chromosome number is 2n = 46 with 12 meta-, 10 submeta-, 16 subtelo-, and 8 acrocentric chromosomes and a fundamental number of FN = 84. An XX/XY sex chromosome system was identified. Mapping of 18S rDNA correlated with the nucleolus organizer regions (Ag-NORs) in the short arms of the 2 X chromosomes in females and in the Y chromosome in males. C-banding revealed heterochromatin in the centromeric regions of all chromosomes, except for pair 3. Prominent sex chromosome-specific heterochromatin amplification was observed, covering the short arms of the Y chromosome almost entirely. FISH with telomeric and tropomyosin (tpm1) sequences, respectively, revealed terminal signals in all chromosomes. The analysis of extended DNA fibers confirmed the colocalization and the interspersed pattern of the telomeric and tpm1 sequences. Thus, this study highlights the remarkable evolutionary dynamism presented by the Amazonian puffer fish regarding the differentiation of a heteromorphic XY sex chromosome system and a particular sex-specific amplification of rDNA sites. This is the first record of such an association in the Tetraodontidae family. © 2017 S. Karger AG, Basel.
Gao, Zhi-Peng; Zhang, Dan-Wei; Yu, Yang; Zhu, Shi-Liang
2017-06-01
We study the dynamics of a transverse-field XY chain driven across quantum critical points by noisy control fields. We characterize the defect density as a function of the quench time and the noise strength and demonstrate that the defect productions for three quench protocols with different scaling exponents exhibit the anti-Kibble-Zurek behavior, whereby slower driving results in more defects. The protocols are quenching through the boundary line between paramagnetic and ferromagnetic phases, quenching across the isolated multicritical point, and quenching along the gapless line, respectively. We also show that the optimal quench time to minimize defects scales as a universal power law of the noise strength in all three cases. Furthermore, by using quantum simulation of the quench dynamics in the spin system with well-designed Landau-Zener crossings in pseudomomentum space, we propose an experimentally feasible scheme to test the predicted anti-Kibble-Zurek behavior of this noisy transverse-field XY chain with two-level systems under controllable fluctuations.
Cherif, Emira; Zehdi, Salwa; Castillo, Karina; Chabrillange, Nathalie; Abdoulkader, Sabira; Pintaud, Jean-Christophe; Santoni, Sylvain; Salhi-Hannachi, Amel; Glémin, Sylvain; Aberlenc-Bertossi, Frédérique
2013-01-01
Whether sex chromosomes are differentiated is an important aspect of our knowledge of dioecious plants, such as date palm (Phoenix dactylifera). In this crop plant, the female individuals produce dates, and are thus the more valuable sex. However, there is no way to identify the sex of date palm plants before reproductive age, and the sex-determining mechanism is still unclear. To identify sex-linked microsatellite markers, we surveyed a set of 52 male and 55 female genotypes representing the geographical diversity of the species. We found three genetically linked loci that are heterozygous only in males. Male-specific alleles allowed us to identify the gender in 100% of individuals. These results confirm the existence of an XY chromosomal system with a nonrecombining XY-like region in the date palm genome. The distribution of Y haplotypes in western and eastern haplogroups allowed us to trace two male ancestral paternal lineages that account for all known Y diversity in date palm. The very low diversity associated with Y haplotypes is consistent with clonal paternal transmission of a nonrecombining male-determining region. Our results establish the date palm as a biological model with one of the most ancient sex chromosomes in flowering plants. © 2012 IRD. New Phytologist © 2013 New Phytologist Trust.
Heisenberg and the Interpretation of Quantum Mechanics
Camilleri, Kristian
2011-09-01
Preface; 1. Introduction; Part I. The Emergence of Quantum Mechanics: 2. Quantum mechanics and the principle of observability; 3. The problem of interpretation; Part II. The Heisenberg-Bohr Dialogue: 4. The wave-particle duality; 5. Indeterminacy and the limits of classical concepts: the turning point in Heisenberg's thought; 6. Heisenberg and Bohr: divergent viewpoints of complementarity; Part III. Heisenberg's Epistemology and Ontology of Quantum Mechanics: 7. The transformation of Kantian philosophy; 8. The linguistic turn in Heisenberg's thought; Conclusion; References; Index.
Directory of Open Access Journals (Sweden)
Ynduráin, Francisco J.
2002-01-01
Full Text Available Not available
Los azares de las onomásticas hacen coincidir en este año el centenario del nacimiento de tres de los más grandes físicos del siglo XX. Dos de ellos, Fermi y Heisenberg, dejaron una marca fundamental en la ciencia (ambos, pero sobre todo el segundo y, el primero, también en la tecnología. Lawrence, indudablemente de un nivel inferior al de los otros dos, estuvo sin embargo en el origen de uno de los desarrollos tecnológicos que han sido básicos para la exploración del universo subnuclear en la segunda mitad del siglo que ha terminado hace poco, el de los aceleradores de partículas.
Fractionalized Z_{2} Classical Heisenberg Spin Liquids.
Rehn, J; Sen, Arnab; Moessner, R
2017-01-27
Quantum spin systems are by now known to exhibit a large number of different classes of spin liquid phases. By contrast, for classical Heisenberg models, only one kind of fractionalized spin liquid phase, the so-called Coulomb or U(1) spin liquid, has until recently been identified: This exhibits algebraic spin correlations and impurity moments, "orphan spins," whose size is a fraction of that of the underlying microscopic degrees of freedom. Here, we present two Heisenberg models exhibiting fractionalization in combination with exponentially decaying correlations. These can be thought of as a classical continuous spin version of a Z_{2} spin liquid. Our work suggests a systematic search and classification of classical spin liquids as a worthwhile endeavor.
DEFF Research Database (Denmark)
Lindhardt Johansen, Marie; Hagen, Casper P; Rajpert-De Meyts, Ewa
2012-01-01
Most previous studies of 45,X/46,XY mosaicism are case reports or have described single aspects of the disease.......Most previous studies of 45,X/46,XY mosaicism are case reports or have described single aspects of the disease....
On moments-based Heisenberg inequalities
Zozor, Steeve; Portesi, Mariela; Sanchez-Moreno, Pablo; Dehesa, Jesus S.
2011-03-01
In this paper we revisit the quantitative formulation of the Heisenberg uncertainty principle. The primary version of this principle establishes the impossibility of refined simultaneous measurement of position x and momentum u for a (1-dimensional) quantum particle in terms of variances: ⩾1/4. Since this inequality applies provided each variance exists, some authors proposed entropic versions of this principle as an alternative (employing Shannon's or Rényi's entropies). As another alternative, we consider moments-based formulations and show that inequalities involving moments of orders other than 2 can be found. Our procedure is based on the Rényi entropic versions of the Heisenberg relation together with the search for the maximal entropy under statistical moments' constraints ( and ). Our result improves a relation proposed very recently by Dehesa et al.. [1] where the same approach was used but starting with the Shannon version of the entropic uncertainty relation. Furthermore, we show that when a =b, the best bound we can find with our approach coincides with that of Ref. [1] and, in addition, for a = b = 2 the variance-based Heisenberg relation is recovered. Finally, we illustrate our results in the cases of d-dimensional hydrogenic systems.
Some properties of correlations of quantum lattice systems in thermal equilibrium
Energy Technology Data Exchange (ETDEWEB)
Fröhlich, Jürg, E-mail: juerg@phys.ethz.ch [Institut für Theoretische Physik, ETH Zürich (Switzerland); Ueltschi, Daniel, E-mail: daniel@ueltschi.org [Department of Mathematics, University of Warwick, Coventry CV4 7AL (United Kingdom)
2015-05-15
Simple proofs of uniqueness of the thermodynamic limit of KMS states and of the decay of equilibrium correlations are presented for a large class of quantum lattice systems at high temperatures. New quantum correlation inequalities for general Heisenberg models are described. Finally, a simplified derivation of a general result on power-law decay of correlations in 2D quantum lattice systems with continuous symmetries is given, extending results of McBryan and Spencer for the 2D classical XY model.
Cosmological implications of Heisenberg's principle
Gonzalo, Julio A
2015-01-01
The aim of this book is to analyze the all important implications of Heisenberg's Uncertainty Principle for a finite universe with very large mass-energy content such as ours. The earlier and main contributors to the formulation of Quantum Mechanics are briefly reviewed regarding the formulation of Heisenberg's Principle. After discussing “indeterminacy” versus ”uncertainty”, the universal constants of physics are reviewed and Planck's units are given. Next, a novel set of units, Heisenberg–Lemaitre units, are defined in terms of the large finite mass of the universe. With the help of Heisenberg's principle, the time evolution of the finite zero-point energy for the universe is investigated quantitatively. Next, taking advantage of the rigorous solutions of Einstein's cosmological equation for a flat, open and mixed universe of finite mass, the most recent and accurate data on the “age” (to) and the expansion rate (Ho) of the universe and their implications are reconsidered.
Thermodynamics of disordered Heisenberg model
Mulanix, Michael; Khatami, Ehsan
Using numerical linked-cluster expansions, we study the thermodynamic properties of the disordered Heisenberg model on the square lattice. We implement a new technique for treating continuous disorder within the NLCE and obtain results for the energy, entropy, specific heat, and spin correlations in the thermodynamic limit.
Generalizations of Heisenberg uncertainty relation
Energy Technology Data Exchange (ETDEWEB)
Trifonov, D.A. [Institute for Nuclear Research, Sofia (Bulgaria)
2002-09-01
A survey on the generalizations of Heisenberg uncertainty relation and a general scheme for their entangled extensions to several states and observables is presented. The scheme is illustrated on the examples of one and two states and canonical quantum observables, and spin and quasi-spin components. Several new uncertainty relations are displayed. (author)
Werner Heisenberg - Life and Work
2002-01-01
Werner Heisenberg (centre) with Wolfgang Pauli (left) and Enrico Fermi on Lake Como, September 1927. An exhibition on the life and work of Werner Heisenberg will be on display in the Main Building (Mezzanine) at CERN from 1 - 23 July. The exhibition was produced by the University Archive of Leipzig University (Gerald Wiemers) and the Max-Planck-Institut für Physik in Munich (Helmut Rechenberg) to mark the centenary of Heisenberg's birth in 1901. German theoretical physicist Werner Karl Heisenberg (5 December 1901 - 1 February 1976) was one of the leading scientists of the 20th century. He carried out important work in nuclear and particle physics, but his most significant contribution was to the development of quantum mechanics. He is best known for his uncertainty principle, which restricts the accuracy with which some properties of atoms and particles - such as position and linear momentum - can be determined simultaneously. In 1932 he was awarded the Noble Prize in Physics 'for the creation of q...
Werner Heisenberg - Life and Work
2002-01-01
Werner Heisenberg (centre) with Wolfgang Pauli and Enrico Fermi, 1927. An exhibition on the life and work of Werner Heisenberg will be on display in the Main Building (Mezzanine) at CERN from 1 - 30 July*. German theoretical physicist Werner Karl Heisenberg (1901 - 1976) was one of the leading scientists of the 20th century. Nobel Prize in Physics in 1932, his most significant contribution was to the development of quantum mechanics. He is best known for his uncertainty principle, which restricts the accuracy with which some properties of atoms and particles can be determined simultaneously. Heisenberg was a keen supporter of CERN, and was as the first chairman of CERN's Scientific Policy Committee in October 1954. A related celebration will take place in the TH Amphitheatre (4/3-006), on Thursday 18 July at 16:00. After an introduction from the Director-General Luciano Maiani, his daughter, Barbara Blum, his last postgraduate, Helmut Rechenberg and Valentin Telegdi will evoke memories of the life and work ...
Optimal transport and von Neumann entropy in a Heisenberg XXZ chain out of equilibrium.
Salerno, Mario; Popkov, Vladislav
2013-02-01
In this paper we investigate the spin currents and the von Neumann entropy (vNE) of a Heisenberg XXZ chain in contact with twisted XY-boundary magnetic reservoirs by means of the Lindblad master equation. Exact solutions for the stationary reduced density matrix are explicitly constructed for chains of small sizes by using a quantum symmetry operation of the system. These solutions are then used to investigate the optimal transport in the chain in terms of the vNE. As a result we show that the maximal spin current always occurs in the proximity of minima of the vNE and for particular choices of parameters (coupling with reservoirs and anisotropy) it can exactly coincide with them. As the coupling is increased, current reversals may occur and in the limit of strong coupling we show that minima of the vNE tend to zero, meaning that the maximal transport is achieved in this case with states that are very close to pure states.
Oxygen hole-doping effects on the spin-chain system Ca2+xY2-xCu5O
Park, K.; Cackowski, T.; Markert, J. T.
2008-04-01
The magnetic properties of the low-dimensional spin-chain system Ca2+xY2-xCu5O were studied as a function of oxygen content and Ca-doping. A series of samples with different oxygen contents were prepared by solid state reaction under various oxygen pressures up to 170 atm and characterized by X-ray diffraction and iodometric titration. Oxygen deficiency was observed to be from δ=0.2-0.4 at 0.2 atm to δ≈0.0 at 170 atm oxygen pressure. Oxygen deficiency increases with Ca-doping at fixed oxygen pressure. The temperature dependence of the magnetic moment and of the specific heat are reported here for the x=0.9 sample with various oxygen deficiencies. The effects of oxygen deficiency on magnetic coupling are compared with Ca-doping. Notably, oxygen content plays a much more critical role in the reduction of magnetic interactions in the CuO2 chains than Ca-doping, even for the same hole concentration.
Superconductivity and magnetic ordering in the mixed ternary Er xY 1-xRh 1.1Sn 3.6 system
Houwman, E. P.; van de Pasch, A. W. M.; Flokstra, J.
1987-07-01
The superconducting transition temperature Tc as well as the magnetic ordering temperature Tm have been determined in the mixed ternary compound Er xY 1-xRh 1.1Sn 3.6 as a function of the Er concentration. Tc decreases from 3.13 K for YRh 1.1Sn 3.6 to 1.1K for ErRh 1.1Sn 3.6. Reentrant superconductivity has been found for x > 0.6. The application of the models of Abrikosov and Gorkov, Maekawa and Tachiki, and Roshen and Ruvalds to this system is discussed. Tc as function of the concentration x is best described by the model of Roshen and Ruvalds assuming a ferromagnetic interaction between the spins. The parameter I2N(0), arising from electron spin, is found to be 0.088 K. The ferromagnetic ordering temperature dependence is described by the theory of Oguchi and Ono, using an effective coordination number z = 6 and an exchange constant of J‧ = 0.30 K.
Magnetic excitations of Kitaev-Heisenberg models on honeycomb lattices
Yamada, Takuto; Suzuki, Takafumi; Suga, Sei-ichiro
2017-11-01
We investigate ground state energies and low-energy excitations of the S = 1/2 Kitaev-Heisenberg model on honeycomb lattices by using dimer series expansions. We find that dimer series expansions can approach the close vicinity of the Kitaev limit, where the Heisenberg interaction is absent, in the lower order expansion than the Ising series expansion. When the system approaches the Kitaev limit, low-lying modes in the zigzag and Néel phases become flatter except for the Bragg wave numbers.
XYZ Quantum Heisenberg Models with p-Orbital Bosons
DEFF Research Database (Denmark)
Pinheiro, Fernanda; Bruun, Georg; Martikainen, Jani-Petri
2013-01-01
We demonstrate how the spin-1/2 XYZ quantum Heisenberg model can be realized with bosonic atoms loaded in the p band of an optical lattice in the Mott regime. The combination of Bose statistics and the symmetry of the p-orbital wave functions leads to a nonintegrable Heisenberg model...... with antiferromagnetic couplings. Moreover, the sign and relative strength of the couplings characterizing the model are shown to be experimentally tunable. We display the rich phase diagram in the one-dimensional case and discuss finite size effects relevant for trapped systems. Finally, experimental issues related...
Heisenberg Limit Superradiant Superresolving Metrology
Wang, Da-Wei; Scully, Marlan O.
2014-01-01
We propose a superradiant metrology technique to achieve the Heisenberg limit super-resolving displacement measurement by encoding multiple light momenta into a three-level atomic ensemble. We use $2N$ coherent pulses to prepare a single excitation superradiant state in a superposition of two timed Dicke states that are $4N$ light momenta apart in momentum space. The phase difference between these two states induced by a uniform displacement of the atomic ensemble has $1/4N$ sensitivity. Expe...
Quantum phase transition in a far-from-equilibrium steady state of an XY spin chain.
Prosen, Tomaz; Pizorn, Iztok
2008-09-05
Using quantization in the Fock space of operators, we compute the nonequilibrium steady state in an open Heisenberg XY spin 1/2 chain of a finite but large size coupled to Markovian baths at its ends. Numerical and theoretical evidence is given for a far-from-equilibrium quantum phase transition with the spontaneous emergence of long-range order in spin-spin correlation functions, characterized by a transition from saturation to linear growth with the size of the entanglement entropy in operator space.
Far-from-equilibrium spin transport in Heisenberg quantum magnets.
Hild, Sebastian; Fukuhara, Takeshi; Schauß, Peter; Zeiher, Johannes; Knap, Michael; Demler, Eugene; Bloch, Immanuel; Gross, Christian
2014-10-03
We study experimentally the far-from-equilibrium dynamics in ferromagnetic Heisenberg quantum magnets realized with ultracold atoms in an optical lattice. After controlled imprinting of a spin spiral pattern with an adjustable wave vector, we measure the decay of the initial spin correlations through single-site resolved detection. On the experimentally accessible time scale of several exchange times, we find a profound dependence of the decay rate on the wave vector. In one-dimensional systems, we observe diffusionlike spin transport with a dimensionless diffusion coefficient of 0.22(1). We show how this behavior emerges from the microscopic properties of the closed quantum system. In contrast to the one-dimensional case, our transport measurements for two-dimensional Heisenberg systems indicate anomalous superdiffusion.
Sharing of classical and quantum correlations via XY interaction
Energy Technology Data Exchange (ETDEWEB)
Wang, Jieci, E-mail: jieciwang@iphy.ac.cn [Institute of Physics and Department of Physics, Hunan Normal University, Changsha, Hunan 410081 (China); Department and Center of Physics, University of Minho, Campus of Gualtar, Braga 4710-057 (Portugal); Silva, Jaime [Department and Center of Physics, University of Minho, Campus of Gualtar, Braga 4710-057 (Portugal); Lanceros-Mendez, Senentxu, E-mail: lanceros@fisica.uminho.pt [Department and Center of Physics, University of Minho, Campus of Gualtar, Braga 4710-057 (Portugal)
2014-09-15
The sharing of classical and quantum correlations via XY interaction is investigated. The model includes two identical networks consisting of n nodes, the ith node of one network sharing a correlated state with the jth node of the other network, while all other nodes are initially unconnected. It is shown that classical correlation, quantum discord as well as entanglement can be shared between any two nodes of the network via XY interaction and that quantum information can be transferred effectively between them. It is found that there is no simple dominating relation between the quantum correlation and entanglement in inertial system.
Optimal quantum parameter estimation of two-qutrit Heisenberg XY chain under decoherence
Yang, Hong-ying; Zheng, Qiang; Zhi, Qi-jun
2017-01-01
Not Available Project supported by the National Natural Science Foundation of China (Grant Nos. 11365006 and 11565010), Guizhou Province Science and Technology Innovation Talent Team, China (Grant No. (2015)4015), Innovation Team Foundation of the Education Department of Guizhou Province, China (Grant No. [2014]35), the Natural Science Foundation of Guizhou Province, China (Grant No. QKHLHZ[2015]7767), and High Level Creative Talents, China (Grant No. (2016)-4008).
Chaotic inflation in supergravity with Heisenberg symmetry
Energy Technology Data Exchange (ETDEWEB)
Antusch, Stefan [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Muenchen (Germany); Bastero-Gil, Mar [Departamento de Fisica Teorica y del Cosmos and Centro Andaluz de Fisica de Particulas Elementales, Universidad de Granada, 19071 Granada (Spain); Dutta, Koushik [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Muenchen (Germany)], E-mail: koushik@mppmu.mpg.de; King, Steve F. [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom); Kostka, Philipp M. [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Muenchen (Germany)
2009-09-07
We propose the introduction of a Heisenberg symmetry of the Kaehler potential to solve the problems with chaotic inflation in supergravity, as a viable alternative to the use of shift symmetry. The slope of the inflaton potential emerges from a small Heisenberg symmetry breaking term in the superpotential. The modulus field of the Heisenberg symmetry is stabilized and made heavy with the help of the large vacuum energy density during inflation. The observable predictions are indistinguishable from those of typical chaotic inflation models, however the form of the inflationary superpotential considered here may be interpreted in terms of sneutrino inflation arising from certain classes of string theory.
Chaotic inflation in supergravity with Heisenberg symmetry
Energy Technology Data Exchange (ETDEWEB)
Antusch, Stefan; Dutta, Koushik; Kostka, Philipp M. [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Muenchen (Germany); Bastero-Gil, Mar [Departamento de Fisica Teorica y del Cosmos, Centro Andaluz de Fisica de Particulas Elementales, Universidad de Granada, 19071 Granada (Spain); King, Steve F. [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom)
2010-07-01
We propose the introduction of a Heisenberg symmetry of the Kaehler potential to solve the problems with chaotic inflation in supergravity, as a viable alternative to the use of shift symmetry. The slope of the inflaton potential emerges from a small Heisenberg symmetry breaking term in the superpotential. The modulus field of the Heisenberg symmetry is stabilized and made heavy with the help of the large vacuum energy density during inflation. The observable predictions are indistinguishable from those of typical chaotic inflation models, however the form of the inflationary superpotential considered here may be interpreted in terms of sneutrino inflation.
Care of women with XY karyotype
DEFF Research Database (Denmark)
Jorgensen, Pernille Bach; Kjartansdóttir, Kristín Rós; Fedder, Jens
2010-01-01
OUTCOME MEASURE(S): Evaluation of etiology, diagnosis, treatment, and associated disorders in XY women. RESULT(S): Many gene mutations can cause abnormal fetal development leading to androgen insensitivity syndrome or gonadal dysgenesis disorders. Females with these disorders have an XY karyotype but look...
Steerneman, A.G.M.; van Perlo -ten Kleij, Frederieke
2005-01-01
The main topic of this paper is the matrix V = A - XY*, where A is a nonsingular complex k x k matrix and X and Y are k x p complex matrices of full column rank. Because properties of the matrix V can be derived from those of the matrix Q = I - XY*, we will consider in particular the case where A =
Quantification of quantum discord in a antiferromagnetic Heisenberg compound
Energy Technology Data Exchange (ETDEWEB)
Singh, H., E-mail: chiranjib@iiserkol.ac.in; Chakraborty, T., E-mail: chiranjib@iiserkol.ac.in; Mitra, C., E-mail: chiranjib@iiserkol.ac.in [Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur Campus, Mohanpur -741252, Nadia, West Bengal (India)
2014-04-24
An experimental quantification of concurrence and quantum discord from heat capacity (C{sub p}) measurement performed over a solid state system has been reported. In this work, thermodynamic measurements were performed on copper nitrate (CN, Cu(NO{sub 3}){sub 2}⋅2.5H{sub 2}O) single crystals which is an alternating antiferromagnet Heisenberg spin 1/2 system. CN being a weak dimerized antiferromagnet is an ideal system to investigate correlations between spins. The theoretical expressions were used to obtain concurrence and quantum discord curves as a function of temperature from heat capacity data of a real macroscopic system, CN.
I grandi della fisica da Platone a Heisenberg
Von Weizsäcker, Carl Friedrich
2002-01-01
Parmenide ; Platone ; Aristotele ; Copernico, Keplero, Galilei ; Galileo Galilei ; Cartesio ; Gottfried Wilhelm Leibniz ; Cartesio, Newton, Leibniz, Kant ; Immanuel Kant ; Johann Wolfgang Goethe ; Robert Meyer ; Albert Einstein ; Niels Bohr ; Paul Adrien Maurice Dirac ; Niels Bohr e Werner Heisenberg, un ricordo del 1932 ; Werner Heisenberg ; Heisenberg, fisico e filosofo ; l'interpretazione filosofica della fisica moderna.
Remark on Heisenberg's principle
Energy Technology Data Exchange (ETDEWEB)
Noguez, G.
1988-07-01
Application of Heisenberg's principle to inertial frame transformations allows a distinction between three commutative groups of reciprocal transformations along one direction: Galilean transformations, dual transformations, and Lorentz transformations. These are three conjugate groups and for a given direction, the related commutators are all proportional to one single conjugation transformation which compensates for uniform and rectilinear motions. The three transformation groups correspond to three complementary ways of measuring space-time as a whole. Heisenberg's Principle then gets another explanation.
Simulation of time-dependent Heisenberg models in one dimension
DEFF Research Database (Denmark)
Volosniev, A. G.; Hammer, H. -W.; Zinner, N. T.
2016-01-01
In this Letter, we provide a theoretical analysis of strongly interacting quantum systems confined by a time-dependent external potential in one spatial dimension. We show that such systems can be used to simulate spin chains described by Heisenberg Hamiltonians in which the exchange coupling...... constants can be manipulated by time-dependent driving of the shape of the external confinement. As illustrative examples, we consider a harmonic trapping potential with a variable frequency and an infinite square well potential with a time-dependent barrier in the middle....
Berglund, Agnethe; Johannsen, Trine H; Stochholm, Kirstine; Viuff, Mette H; Fedder, Jens; Main, Katharina M; Gravholt, Claus H
2017-11-20
Little is known about long-term health outcomes in phenotypic females with 46,XY disorders of sex development (XY females) and the socioeconomic profile is not described in detail. To describe morbidity, mortality and socioeconomic status in XY females in a comparison to the general population. A nationwide registry study with complete follow-up. A uniform public health care system. 123 XY females karyotyped in Denmark during 1960-2012 and a randomly selected age-matched control cohort of 12,300 females and 12,300 males from the general population. None. combined mortality and morbidity as well as chapter-specific morbidity. Medicinal use and socioeconomic profile, including education, cohabitation and retirement. Compared to female controls overall morbidity was increased in XY females (HR=1.72, CI: 1.43-2.08) but not when disregarding diagnostic chapters associated with either the specific DSD diagnosis or pregnancy and birth (HR=1.13, CI: 0.93-1.37). Mortality was similar to controls (HR=0.79, CI: 0.35-1.77). Cohabitation (HR=0.44, CI: 0.33-0.58) and motherhood (HR=0.10, CI=0.05-0.18) were reduced in XY females but educational level (HR=0.92, CI: 0.61-1.37) was similar to controls. Income diverged during life with XY females having respectively a lower and higher income in the younger and older years. Morbidity was not increased in XY females when disregarding diagnoses closely related to the DSD condition. Judged on educational level and income XY females perform well on the labor market. However, DSD seems to impact on the prospects of family life..
Quantum phase transitions in spin-lattice systems
Ristig, M; Farnell, D; Kuerten, K
2002-01-01
Classical and quantized spins on a lattice interacting via unisotropic Heisenberg forces are important and illuminating models for an understanding of magnetic properties and phase transitions in solids, of structural phase transitions in ferroelectrics, and of transitions in quasi-spin systems. Further, many-body theories of spin lattices may be fruitfully related to latticized quantum-field theories within a Hamiltonian formulation. A close formal relationship exists, for example, between an O(2) model of the XY type and the O(4) model of chiral meson-field theory. Microscopic calculations are reviewed on the ground and excited states of such systems employing the microscopic correlated basis-functions (CBF) theory that has been so successful in the theory of quantum fluids and in nuclear physics. Reported are numerical results on the order parameters, phase boundaries, and other physical quantities of interest for the transverse Ising model, the spin-half XY model, the O(2) model for Josephson junction arr...
Polarizability tensor and Kramers-Heisenberg induction
Wijers, Christianus M.J.
2004-01-01
A general expression for the semiclassical, nonrelativistic linear polarizability of an arbitrary volume element V has been derived in the long wavelength approximation. The derivation starts from the expectation value of the dipole strength, as in the original Kramers-Heisenberg paper about optical
Classifying tight Weyl-Heisenberg frames
DEFF Research Database (Denmark)
Cazsazza, P.; Janssen, A. J. E. M.; Christensen, Ole
1999-01-01
A Weyl-Heisenberg frame for L^2(R) is a frame consisting of translates and modulates of a fixed function. In this paper we give necessary and sufficient conditions for this family to form a tight WH-frame. This allows us to write down explicitly all functions g for which all translates and modula...
Books by and about Werner Heisenberg
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 9; Issue 8. Books by and about Werner Heisenberg. N Mukunda. Book Review Volume 9 Issue 8 August 2004 pp 83-86. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/009/08/0083-0086. Author Affiliations.
Frayn's "Heisenberg": Fact or Fiction? 9 -O ...
Indian Academy of Sciences (India)
2002-03-02
Mar 2, 2002 ... climbing, music or the spiritual which he called the central order. I have said this in other contexts already, but it bears repeating: the emotional portrayal of the Copenhagen Heisenberg is off in some respects. His demeanor was modest, understated, even somewhat shy, though always friendly, forward, and ...
Spin-density functional for exchange anisotropic Heisenberg model
Energy Technology Data Exchange (ETDEWEB)
Prata, G.N.; Penteado, P.H.; Souza, F.C. [Departamento de Fisica e Informatica, Instituto de Fisica de Sao Carlos, Universidade de Sao Paulo, CP 369, Sao Carlos - SP (Brazil); Libero, Valter L., E-mail: valter@if.sc.usp.b [Departamento de Fisica e Informatica, Instituto de Fisica de Sao Carlos, Universidade de Sao Paulo, CP 369, Sao Carlos - SP (Brazil)
2009-10-15
Ground-state energies for antiferromagnetic Heisenberg models with exchange anisotropy are estimated by means of a local-spin approximation made in the context of the density functional theory. Correlation energy is obtained using the non-linear spin-wave theory for homogeneous systems from which the spin functional is built. Although applicable to chains of any size, the results are shown for small number of sites, to exhibit finite-size effects and allow comparison with exact-numerical data from direct diagonalization of small chains.
Generation of fertile and fecund F0 XY female mice from XY ES cells.
Kuno, Junko; Poueymirou, William T; Gong, Guochun; Siao, Chia-Jen; Clarke, Georgia; Esau, Lakeisha; Kojak, Nada; Posca, Julita; Atanasio, Amanda; Strein, John; Yancopoulos, George D; Lai, Ka-Man Venus; DeChiara, Thomas M; Frendewey, David; Auerbach, Wojtek; Valenzuela, David M
2015-02-01
Known examples of male to female sex reversal in mice are caused by either strain incompatibilities or mutations in genes required for male sex determination. The resultant XY females are often sterile or exhibit very poor fertility. We describe here embryonic stem (ES) cell growth conditions that promote the production of healthy, anatomically normal fertile and fecund female F0 generation mice completely derived from gene-targeted XY male ES cells. The sex reversal is a transient trait that is not transmitted to the F1 progeny. Growth media with low osmolality and reduced sodium bicarbonate, maintained throughout the gene targeting process, enhance the yield of XY females. As a practical application of the induced sex reversal, we demonstrate the generation of homozygous mutant mice ready for phenotypic studies by the breeding of F0 XY females with their isogenic XY male clonal siblings, thereby eliminating one generation of breeding and the associated costs.
Chaotic dynamics of Heisenberg ferromagnetic spin chain with bilinear and biquadratic interactions
Blessy, B. S. Gnana; Latha, M. M.
2017-10-01
We investigate the chaotic dynamics of one dimensional Heisenberg ferromagnetic spin chain by constructing the Hamiltonian equations of motion. We present the trajectory and phase plots of the system with bilinear and also biquadratic interactions. The stability of the system is analysed in both cases by constructing the Jacobian matrix and by measuring the Lyapunov exponents. The results are illustrated graphically.
Strecka, Jozef; Cisarova, Jana
2013-01-01
A full energy spectrum of the spin-1/2 Heisenberg cubic cluster is used to investigate a low-temperature magnetization process and adiabatic demagnetization of this zero-dimensional 2x2x2 quantum spin system. It is shown that the antiferromagnetic spin-1/2 Heisenberg cube exhibits at low enough temperatures a stepwise magnetization curve with four intermediate plateaux at zero, one quarter, one half, and three quarters of the saturation magnetization. We have also found the enhanced magnetoca...
Heisenberg antiferromagnets with exchange and cubic anisotropies
Energy Technology Data Exchange (ETDEWEB)
Bannasch, G [MPI fuer Physik komplexer Systeme, 01187 Dresden (Germany); Selke, W, E-mail: selke@physik.rwth-aachen.d [Institut fuer Theoretische Physik, RWTH Aachen University and JARA-SIM, 52056 Aachen (Germany)
2010-01-01
We study classical Heisenberg antiferromagnets with uniaxial exchange anisotropy and a cubic anisotropy term on simple cubic lattices in an external magnetic field using ground state considerations and extensive Monte Carlo simulations. In addition to the antiferromagnetic phase field-induced spin-flop and non-collinear, biconical phases may occur. Phase diagrams and critical as well as multicritical phenomena are discussed. Results are compared to previous findings.
Park, Keeseong; Cackowski, Theodore; Markert, John
2008-03-01
A quasi-one dimensional system, Ca2+xY2-xCu5O10-δ (CaYCuO) is studied to compare the magnetic effects of cation doping with those of oxygen deficiency. Hole doping (p) due to cation concentration (x) and oxygen deficiency (δ) in other copper oxides is often observed to obey p = x - 2 δ. CaYCuO has a simple edge shared CuO structure and is hole dopable up to a formal copper valence of 2.4. Various Ca doped CaYCuO specimens were fabricated in different oxygen environments, including high pressure oxygen up to 170 atm. X-ray diffraction and iodometric titration were used to confirm phase and oxygen content. Samples are found to be more oxygen deficient with increasing cation doping. Magnetic moment and specific heat were measured. The antiferromagnetic phase was observed up to x = 1.0 doping for fully oxygenated specimens. N'eel temperatures decreased with increasing cation doping and decreasing oxygen deficiency. The decrease in N'eel temperature is found to be more than expected from hole doping p = x - 2 δ. A new quantity that describes all of the behavior of N'eel temperature, p' = x - (2/3) δ, is proposed.
Heisenberg, his wife s account; Heisenberg, le temoignage de sa femme
Energy Technology Data Exchange (ETDEWEB)
Heisenberg, E.
1990-12-31
A wife tells about her husband life, Werner Heisenberg, Physics Nobel Price in 1932. After a happy childhood, this brilliant student was Albert Einstein, Niels Bohr, Arnold Sommerfeld s student. But at the nazism time, the great physician refused to leave his country, guaranteeing the Hitler regime and taking part in effort of war, that is to say the run to the bomb. The account of Elisabeth Heisenberg, although subjective, allows to understand the scientist s behaviour face terrifying realities of his time. (N.C.).
Dimensional crossover in the XY-compound YBa_{2}Cu_{3}O_{6}_{+}_{x}
DEFF Research Database (Denmark)
Montfrooij, W.; Casalta, H.; Schleger, P.
1998-01-01
The magnetic ordering of the bilayered Heisenberg antiferromagnet YBa2Cu3O6+x with weak XY-anisotropy was investigated for temperatures close to the magnetic transition temperature T-N. We find that the magnitude of the sublattice magnetization is well described by a power law similar to epsilon(...... of the magnetic reflections (1/2h,1/2h,0), indicative of a small component of the electron moments perpendicular to the ab-plane. (C) 1998 Elsevier Science B.V. All rights reserved....
Metamagnetic phase transition of the antiferromagnetic Heisenberg icosahedron.
Schröder, Christian; Schmidt, Heinz-Jürgen; Schnack, Jürgen; Luban, Marshall
2005-05-27
The observation of hysteresis effects in single molecule magnets like Mn12-acetate has initiated ideas of future applications in storage technology. The appearance of a hysteresis loop in such compounds is an outcome of their magnetic anisotropy. In this Letter we report that magnetic hysteresis occurs in a spin system without any anisotropy, specifically where spins mounted on the vertices of an icosahedron are coupled by antiferromagnetic isotropic nearest-neighbor Heisenberg interaction giving rise to geometric frustration. At T = 0 this system undergoes a first-order metamagnetic phase transition at a critical field Bc between two distinct families of ground state configurations. The metastable phase of the system is characterized by a temperature and field dependent survival probability distribution.
InXy and SeXy, compact heterologous reporter proteins for mammalian cells.
Fluri, David A; Kelm, Jens M; Lesage, Guillaume; Baba, Marie Daoud-El; Fussenegger, Martin
2007-10-15
Mammalian reporter proteins are essential for gene-function analysis, drugscreening initiatives and as model product proteins for biopharmaceutical manufacturing. Bacillus subtilis can maintain its metabolism by secreting Xylanase A (XynA), which converts xylan into shorter xylose oligosaccharides. XynA is a family 11 xylanase monospecific for D-xylose containing substrates. Mammalian cells transgenic for constitutive expression of wild-type xynA showed substantial secretion of this prokaryotic enzyme. Deletion analysis confirmed that a prokaryotic signal sequence encoded within the first 81 nucleotides was compatible with the secretory pathway of mammalian cells. Codon optimization combined with elimination of the prokaryotic signal sequence resulted in an exclusively intracellular mammalian Xylanase A variant (InXy) while replacement by an immunoglobulin-derived secretion signal created an optimal secreted Xylanase A derivative (SeXy). A variety of chromogenic and fluorescence-based assays adapted for use with mammalian cells detected InXy and SeXy with high sensitivity and showed that both reporter proteins resisted repeated freeze/thaw cycles, remained active over wide temperature and pH ranges, were extremely stable in human serum stored at room temperature and could independently be quantified in samples also containing other prominent reporter proteins such as the human placental alkaline phosphatase (SEAP) and the Bacillus stearothermophilus-derived secreted alpha-amylase (SAMY). Glycoprofiling revealed that SeXy produced in mammalian cells was N- glycosylated at four different sites, mutation of which resulted in impaired secretion. SeXy was successfully expressed in a variety of mammalian cell lines and primary cells following transient transfection and transduction with adeno-associated virus particles (AAV) engineered for constitutive SeXy expression. Intramuscular injection of transgenic AAVs into mice showed significant SeXy levels in the bloodstream
Vincent, Maxence S.; Durand, Eric; Cascales, Eric
2016-01-01
The Type IX secretion system (T9SS) is a versatile multi-protein complex restricted to bacteria of the Bacteriodetes phylum and responsible for the secretion or cell surface exposition of diverse proteins that participate to S-layer formation, gliding motility or pathogenesis. The T9SS is poorly characterized but a number of proteins involved in the assembly of the secretion apparatus in the oral pathogen Porphyromonas gingivalis have been identified based on genome substractive analyses. Among these proteins, PorY, and PorX encode typical two-component system (TCS) sensor and CheY-like response regulator respectively. Although the porX and porY genes do not localize at the same genetic locus, it has been proposed that PorXY form a bona fide TCS. Deletion of porX in P. gingivalis causes a slight decrease of the expression of a number of other T9SS genes, including sov, porT, porP, porK, porL, porM, porN, and porY. Here, we show that PorX and the soluble cytoplasmic domain of PorY interact. Using electrophoretic mobility shift, DNA-protein co-purification and heterologous host expression assays, we demonstrate that PorX does not bind T9SS gene promoters and does not directly regulate expression of the T9SS genes. Finally, we show that PorX interacts with the cytoplasmic domain of PorL, a component of the T9SS membrane core complex and propose that the CheY-like PorX protein might be involved in the dynamics of the T9SS. PMID:27630829
Directory of Open Access Journals (Sweden)
Maxence S Vincent
2016-08-01
Full Text Available The Type IX secretion system (T9SS is a versatile multi-protein complex restricted to bacteria of the Bacteriodetes phylum and responsible for the secretion of surface attachment of diverse proteins that participate to S-layer formation, gliding motility or pathogenesis. The T9SS is poorly characterized but a number of proteins involved in the assembly of the secretion apparatus in the oral pathogen Porphyromonas gingivalis have been identified based on genome substractive analyses. Among these proteins, PorY and PorX encode typical two-component system (TCS sensor and CheY-like response regulator respectively. Although the porX and porY genes do not localize at the same genetic locus, it has been proposed that PorXY form a bona fide TCS. Deletion of the porX in P. gingivalis causes a slight decrease of the expression of a number of other T9SS genes, including sov, porT, porP, porK, porL, porM, porN and porY. Here, we show that PorX and the soluble cytoplasmic domain of PorY interact. Using electrophoretic mobility shift, DNA-protein co-purification and heterologous host expression assays, we showed that PorX does not bind and does not directly regulate expression of the T9SS genes. Finally, we show that PorX interacts with the cytoplasmic domain of PorL, a component of the T9SS membrane core complex and propose that the CheY-like PorX protein might be involved in the dynamics of the T9SS.
Incommensurate correlations in the anisotropic triangular Heisenberg lattice
Weichselbaum, Andreas; White, Steven R.
2011-12-01
We study the anisotropic spin-1/2 antiferromagnetic triangular Heisenberg lattice in two dimensions, seen as a set of chains with couplings J (J') along (in-between) chains, respectively. Our focus is on the incommensurate correlation that emerges in this system in a wide parameter range due to the intrinsic frustration of the spins. We study this system with traditional density matrix renormalization group using cylindrical boundary conditions to least constrain possible incommensurate order. Despite that the limit of essentially decoupled chains J'/J≲0.5 is not very accessible numerically, it appears that the spin-spin correlations remain incommensurate for any finite 0JC', where JC'/J>1. The incommensurate wave vector qJ, however, approaches the commensurate value corresponding to the antiferromagnetic correlation of a single chain very rapidly with decreasing J'/J, roughly as qJ˜π-c1(J'/J)ne-c2J/J'.
Distinguishing XY from Ising electron nematics
Basak, S.; Carlson, E. W.
2017-08-01
At low temperatures in ultraclean GaAs-AlGaAs heterojunctions, high Landau levels near half-integral filling break rotational symmetry, leading to increasingly anisotropic transport properties as temperature is lowered below ˜150 mK . While the onset of transport anisotropy is well described by an XY model of an electron nematic in the presence of a weak uniform symmetry-breaking term, the low-temperature behavior deviates significantly from this model. We find that inclusion of interactions between the electron nematic and the underlying crystalline lattice in the form of a fourfold symmetry-breaking term is sufficient to describe the entire temperature dependence of the transport anisotropy at ν =9 /2 . This implies that this electron nematic is in the Ising universality class. We propose new experimental tests that can distinguish whether any two-dimensional electron nematic is in the XY or Ising universality class.
Science 101: What, Exactly, Is the Heisenberg Uncertainty Principle?
Robertson, Bill
2016-01-01
Bill Robertson is the author of the NSTA Press book series, "Stop Faking It! Finally Understanding Science So You Can Teach It." In this month's issue, Robertson describes and explains the Heisenberg Uncertainty Principle. The Heisenberg Uncertainty Principle was discussed on "The Big Bang Theory," the lead character in…
Photometric Study on the Spot-Double Star XY Urase Majoris (I
Directory of Open Access Journals (Sweden)
Woo-Baik Lee
1988-06-01
Full Text Available The long-term observational properties of the photometric behaviours of the short period (p=0.48 day eclipsing binary system XY UMa are discussed. They are based on the UBV observations, which were carried out by Geyer in the years 1955-1961, 1968, 1975-1984. Light curves of XY UMa revealed very large changes not only between consecutive observing nights, but also from season to season. Between 1955 and 1984, the mean system brightness increased about 30% during this time intervals, meanwhile, the orbital period of this system was constant whithin 1.6% of its period. The colour index curve shows similar variations like the light curve but with a phase offset oscillation around the time instants of the primary minima. Observational evidence for photospheric and chromospheric activities on the XY UMa are also discussed.
Nematic Bond Theory of Heisenberg Helimagnets
Schecter, Michael; Syljuâsen, Olav F.; Paaske, Jens
2017-10-01
We study classical two-dimensional frustrated Heisenberg models with generically incommensurate ground states. A new theory for the lattice-nematic "order by disorder" transition is developed based on the self-consistent determination of the effective exchange coupling bonds. In our approach, fluctuations of the constraint field imposing conservation of the local magnetic moment drive nematicity at low temperatures. The critical temperature is found to be highly sensitive to the peak helimagnetic wave vector, and vanishes continuously when approaching rotation symmetric Lifshitz points. Transitions between symmetry distinct nematic orders may occur by tuning the exchange parameters, leading to lines of bicritical points.
Uncertainty inequalities for the Heisenberg group
Indian Academy of Sciences (India)
on ϕ ∈ L2(Rn) by πλ(z, t)ϕ(ξ) = eiλteiλ(x·ξ+1. 2 x·y)ϕ(ξ + y). Given a function f ∈ L1(Hn), its group Fourier transform ˆf is defined to be the operator- ... the continuous wavelet transform on the. Heisenberg group. Let Pα(α ∈ Nn) be the projection from L2(Rn) to one-dimensional subspace spanned by α. For σ = + or −, define.
Classical and quantum anisotropic Heisenberg antiferromagnets
Directory of Open Access Journals (Sweden)
W. Selke
2009-01-01
Full Text Available We study classical and quantum Heisenberg antiferromagnets with exchange anisotropy of XXZ-type and crystal field single-ion terms of quadratic and quartic form in a field. The magnets display a variety of phases, including the spin-flop (or, in the quantum case, spin-liquid and biconical (corresponding, in the quantum lattice gas description, to supersolid phases. Applying ground-state considerations, Monte Carlo and density matrix renormalization group methods, the impact of quantum effects and lattice dimension is analysed. Interesting critical and multicritical behaviour may occur at quantum and thermal phase transitions.
Discrete Flavour Symmetries from the Heisenberg Group
Floratos, E.G.
2016-01-01
Non-abelian discrete symmetries are of particular importance in model building. They are mainly invoked to explain the various fermion mass hierarchies and forbid dangerous superpotential terms. In string models they are usually associated to the geometry of the compactification manifold and more particularly to the magnetised branes in toroidal compactifications. Motivated by these facts, in this note we propose a unified framework to construct representations of finite discrete family groups based on the automorphisms of the discrete and finite Heisenberg group. We focus in particular in the $PSL_2(p)$ groups which contain the phenomenologically interesting cases.
Graphics of (X,Y) spectrum for microcomputer; Graficado de espectro (X,Y) para microcomputadora
Energy Technology Data Exchange (ETDEWEB)
Macias B, L.R
1991-08-15
When carrying out diffraction works is frequently required to visualize the spectra of the data obtained in order to analyzing them. The design for the obtaining of data in the neutron diffractometer by means of the microcomputer allows to store them in a file by means of the one which transferring to the CYBER system so that by means of its utilities the mentioned spectrum is observed in a graph. In diffraction works, it is sought to study crystalline materials by means of the execution of the Bragg law by that the mounted sample on the diffractometer is subjected to a scanning of the sample with a radiation of a well-known wavelength and this way varying the angles, the corresponding interplanar distances are determined. The main objective of this work, is starting of a data set generated by the diffractometer, to generate the graph of the corresponding (X,Y) spectra in visual form in the screen of a microcomputer and if it is required, to obtain the graph in printed form by means of the same computer program for microcomputer. (Author)
Quantum discord in the transverse field XY chains with three-spin interaction
Energy Technology Data Exchange (ETDEWEB)
Lei, Shuguo [Department of Physics and Institute of Theoretical Physics, Nanjing Normal University, Nanjing 210023 (China); College of Science, Nanjing Tech University, Nanjing 211816 (China); Tong, Peiqing, E-mail: pqtong@njnu.edu.cn [Department of Physics and Institute of Theoretical Physics, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems, Nanjing Normal University, Nanjing 210023 (China)
2015-04-15
The ground state quantum discord in the transverse field anisotropic and isotropic XY chains with XZY–YZX type three-spin interaction has been studied. The three-spin interaction induces new gapless quantum phases in the transverse field anisotropic XY chain besides the ferromagnetic and paramagnetic phases. It is found that the first-order derivative of the quantum discord at the Ising type transition between the gapped phases has a logarithmic divergence scaling with the system size. However, the first-order derivative of the quantum discord at the quantum phase transitions between the gapped and gapless phases does not increase with the system size. For the transverse field isotropic XY chain, the first-order derivative of the quantum discord at the quantum phase transitions between the gapless phases has a similar behavior with that between the gapped and gapless phases.
Quantum spin transistor with a Heisenberg spin chain
Marchukov, O. V.; Volosniev, A. G.; Valiente, M.; Petrosyan, D.; Zinner, N. T.
2016-01-01
Spin chains are paradigmatic systems for the studies of quantum phases and phase transitions, and for quantum information applications, including quantum computation and short-distance quantum communication. Here we propose and analyse a scheme for conditional state transfer in a Heisenberg XXZ spin chain which realizes a quantum spin transistor. In our scheme, the absence or presence of a control spin excitation in the central gate part of the spin chain results in either perfect transfer of an arbitrary state of a target spin between the weakly coupled input and output ports, or its complete blockade at the input port. We also discuss a possible proof-of-concept realization of the corresponding spin chain with a one-dimensional ensemble of cold atoms with strong contact interactions. Our scheme is generally applicable to various implementations of tunable spin chains, and it paves the way for the realization of integrated quantum logic elements. PMID:27721438
Figueiredo, T. P.; Rocha, J. C. S.; Costa, B. V.
2017-12-01
Although the topological Berezinskii-Kosterlitz-Thouless transition was for the first time described by 40 years ago, it is still a matter of discussion. It has been used to explain several experiments in the most diverse physical systems. In contrast with the ordinary continuous phase transitions the BKT-transition does not break any symmetry. However, in some contexts it can easily be confused with other continuous transitions, in general due to an insufficient data analysis. The two-dimensional XY (or sometimes called planar rotator) spin model is the fruit fly model describing the BKT transition. As demonstrated by Bramwell and Holdsworth (1993) the finite-size effects are more important in two-dimensions than in others due to the logarithmic system size dependence of the properties of the system. Closely related is the anisotropic two dimensional Heisenberg model (AH). Although they have the same Hamiltonian the spin variable in the former has only two degrees of freedom while the AH has three. Many works treat the AH model as undergoing a transition in the same universality class as the XY model. However, its characterization as being in the BKT class of universality deserve some investigation. This paper has two goals. First, we describe an analytical evidence showing that the AH model is in the BKT class of universality. Second, we make an extensive simulation, using the numerical Replica Exchange Wang-Landau method that corroborate our analytical calculations. From our simulation we obtain the BKT transition temperature as TBKT = 0 . 6980(10) by monitoring the susceptibility, the two point correlation function and the helicity modulus. We discuss the misuse of the fourth order Binder's cumulant to locate the transition temperature. The specific heat is shown to have a non-critical behavior as expected in the BKT transition. An analysis of the two point correlation function at low temperature, C(r) ∝r - η(T), shows that the exponent, η, is consistent
Ulu, Ferhat; Kim, Sung-Min; Yokoyama, Toshifumi; Yamazaki, Yukiko
2017-01-01
Abstract Male differentiation of primordial germ cells (PGCs) is initiated by the inhibition of entry into meiosis and exposure to male-inducing factor(s), which are regulated by somatic elements of the developing gonad. Fibroblast growth factor 9 (FGF9) produced by pre-Sertoli cells is essential for male gonadal differentiation and also contributes to survival and male differentiation of XY PGCs. However, it is not clear how FGF9 regulates PGC fate. Using a PGC culture system, we identified dose-dependent, fate-determining functions of FGF9 in XY PGCs. Treatment with low levels of FGF9 (0.2 ng/ml) increased expression of male-specific Dnmt3L and Nanos2 in XY PGCs. Conversely, treatment with high levels of FGF9 (25 ng/ml) suppressed male-specific gene expression and stimulated proliferation of XY PGCs. Western blotting showed that low FGF9 treatment enhanced p38 MAPK (mitogen-activated protein kinase) phosphorylation in the same cells. In contrast, high FGF9 treatment significantly stimulated the ERK (extracellular signal-regulated kinase)1/2 signaling pathway in XY PGCs. We investigated the relationship between the ERK1/2 signaling pathway stimulated by high FGF9 and regulation of PGC proliferation. An ERK1/2 inhibitor (U0126) suppressed the PGC proliferation that would otherwise be stimulated by high FGF9 treatment, and increased Nanos2 expression in XY PGCs. Conversely, a p38 MAPK inhibitor (SB202190) significantly suppressed Nanos2 expression that would otherwise be stimulated by low FGF9 in XY PGCs. Taken together, our results suggest that stage-specific expression of FGF9 in XY gonads regulates the balance between proliferation and differentiation of XY PGCs in a dose-dependent manner. PMID:28395336
Ulu, Ferhat; Kim, Sung-Min; Yokoyama, Toshifumi; Yamazaki, Yukiko
2017-01-01
Male differentiation of primordial germ cells (PGCs) is initiated by the inhibition of entry into meiosis and exposure to male-inducing factor(s), which are regulated by somatic elements of the developing gonad. Fibroblast growth factor 9 (FGF9) produced by pre-Sertoli cells is essential for male gonadal differentiation and also contributes to survival and male differentiation of XY PGCs. However, it is not clear how FGF9 regulates PGC fate. Using a PGC culture system, we identified dose-dependent, fate-determining functions of FGF9 in XY PGCs. Treatment with low levels of FGF9 (0.2 ng/ml) increased expression of male-specific Dnmt3L and Nanos2 in XY PGCs. Conversely, treatment with high levels of FGF9 (25 ng/ml) suppressed male-specific gene expression and stimulated proliferation of XY PGCs. Western blotting showed that low FGF9 treatment enhanced p38 MAPK (mitogen-activated protein kinase) phosphorylation in the same cells. In contrast, high FGF9 treatment significantly stimulated the ERK (extracellular signal-regulated kinase)1/2 signaling pathway in XY PGCs. We investigated the relationship between the ERK1/2 signaling pathway stimulated by high FGF9 and regulation of PGC proliferation. An ERK1/2 inhibitor (U0126) suppressed the PGC proliferation that would otherwise be stimulated by high FGF9 treatment, and increased Nanos2 expression in XY PGCs. Conversely, a p38 MAPK inhibitor (SB202190) significantly suppressed Nanos2 expression that would otherwise be stimulated by low FGF9 in XY PGCs. Taken together, our results suggest that stage-specific expression of FGF9 in XY gonads regulates the balance between proliferation and differentiation of XY PGCs in a dose-dependent manner. © The Author 2016. Published by Oxford University Press on behalf of Society for the Study of Reproduction.
Energy Technology Data Exchange (ETDEWEB)
Alécio, Raphael C.; Lyra, Marcelo L. [Instituto de Física, Universidade Federal de Alagoas, 57072–970 Maceió-AL (Brazil); Strečka, Jozef [Department of Theoretical Physics and Astrophysics, Faculty of Science, P. J. Šafárik University, Park Angelinum 9, 040 01 Košice (Slovakia)
2016-11-01
The ground-state phase diagram, magnetization process and bipartite entanglement of the frustrated spin-1/2 Ising-Heisenberg and Heisenberg triangular tube (three-leg ladder) are investigated in a non-zero external magnetic field. The exact ground-state phase diagram of the spin-1/2 Ising-Heisenberg tube with Heisenberg intra-rung and Ising inter-rung couplings consists of six distinct gapped phases, which manifest themselves in a magnetization curve as intermediate plateaus at zero, one-third and two-thirds of the saturation magnetization. Four out of six available ground states exhibit quantum entanglement between two spins from the same triangular unit evidenced by a non-zero concurrence. Density-matrix renormalization group calculations are used in order to construct the ground-state phase diagram of the analogous but purely quantum spin-1/2 Heisenberg tube with Heisenberg intra- and inter-rung couplings, which consists of four gapped and three gapless phases. The Heisenberg tube shows a continuous change of the magnetization instead of a plateau at zero magnetization, while the intermediate one-third and two-thirds plateaus may be present or not in the zero-temperature magnetization curve. - Highlights: • Ground-state properties of Ising-Heisenberg and full Heisenberg spin tubes are studied. • Phases with 1/3 and 2/3 magnetization plateaus are present in both models. • We unveil the region in the parameter space on which inter-rung quantum fluctuations are relevant. • The full Heisenberg tube exhibits quantum bipartite entanglement between intra- as well as inter-rung spins.
Energy Technology Data Exchange (ETDEWEB)
Masood, Syed [Department of Physics, International Islamic University, H-10 Sector, Islamabad (Pakistan); Faizal, Mir, E-mail: mirfaizalmir@gmail.com [Irving K. Barber School of Arts and Sciences, University of British Columbia – Okanagan, Kelowna, BC V1V 1V7 (Canada); Department of Physics and Astronomy, University of Lethbridge, Lethbridge, AB T1K 3M4 (Canada); Zaz, Zaid [Department of Electronics and Communication Engineering, University of Kashmir, Srinagar, Kashmir, 190006 (India); Ali, Ahmed Farag [Department of Physics, Faculty of Science, Benha University, Benha, 13518 (Egypt); Raza, Jamil [Department of Physics, International Islamic University, H-10 Sector, Islamabad (Pakistan); Shah, Mushtaq B. [Department of Physics, National Institute of Technology, Srinagar, Kashmir, 190006 (India)
2016-12-10
In this paper, we will propose the most general form of the deformation of Heisenberg algebra motivated by the generalized uncertainty principle. This deformation of the Heisenberg algebra will deform all quantum mechanical systems. The form of the generalized uncertainty principle used to motivate these results will be motivated by the space fractional quantum mechanics, and non-locality in quantum mechanical systems. We also analyse a specific limit of this generalized deformation for one dimensional system, and in that limit, a nonlocal deformation of the momentum operator generates a local deformation of all one dimensional quantum mechanical systems. We analyse the low energy effects of this deformation on a harmonic oscillator, Landau levels, Lamb shift, and potential barrier. We also demonstrate that this deformation leads to a discretization of space.
Achieving the Heisenberg limit in quantum metrology using quantum error correction.
Zhou, Sisi; Zhang, Mengzhen; Preskill, John; Jiang, Liang
2018-01-08
Quantum metrology has many important applications in science and technology, ranging from frequency spectroscopy to gravitational wave detection. Quantum mechanics imposes a fundamental limit on measurement precision, called the Heisenberg limit, which can be achieved for noiseless quantum systems, but is not achievable in general for systems subject to noise. Here we study how measurement precision can be enhanced through quantum error correction, a general method for protecting a quantum system from the damaging effects of noise. We find a necessary and sufficient condition for achieving the Heisenberg limit using quantum probes subject to Markovian noise, assuming that noiseless ancilla systems are available, and that fast, accurate quantum processing can be performed. When the sufficient condition is satisfied, a quantum error-correcting code can be constructed that suppresses the noise without obscuring the signal; the optimal code, achieving the best possible precision, can be found by solving a semidefinite program.
Directory of Open Access Journals (Sweden)
Syed Masood
2016-12-01
Full Text Available In this paper, we will propose the most general form of the deformation of Heisenberg algebra motivated by the generalized uncertainty principle. This deformation of the Heisenberg algebra will deform all quantum mechanical systems. The form of the generalized uncertainty principle used to motivate these results will be motivated by the space fractional quantum mechanics, and non-locality in quantum mechanical systems. We also analyse a specific limit of this generalized deformation for one dimensional system, and in that limit, a nonlocal deformation of the momentum operator generates a local deformation of all one dimensional quantum mechanical systems. We analyse the low energy effects of this deformation on a harmonic oscillator, Landau levels, Lamb shift, and potential barrier. We also demonstrate that this deformation leads to a discretization of space.
High-precision control of LSRM based X-Y table for industrial applications.
Pan, J F; Cheung, Norbert C; Zou, Yu
2013-01-01
The design of an X-Y table applying direct-drive linear switched reluctance motor (LSRM) principle is proposed in this paper. The proposed X-Y table has the characteristics of low cost, simple and stable mechanical structure. After the design procedure is introduced, an adaptive position control method based on online parameter identification and pole-placement regulation scheme is developed for the X-Y table. Experimental results prove the feasibility and its priority over a traditional PID controller with better dynamic response, static performance and robustness to disturbances. It is expected that the novel two-dimensional direct-drive system find its applications in high-precision manufacture area. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.
Photometric Study on the Spot-Double Star XY Ursae Majoris (II
Directory of Open Access Journals (Sweden)
Woo-Baik Lee
1988-12-01
Full Text Available The photometric behaviour of XY UMa, an eclipsing binary showing photospheric and chromospheric activity, has been described by spot hypothesis. They are based on the all the available UBV light curves, which were carried out by Geyer since 1955. A "spherical rectangular" spot model shows very pronounced spot activities during the last 30 years. On the average, the spot covered about 16% of the visible hemisphere. Observational evidence for photospheric and chromospheric activities on the XY UMa and related systems are also discussed.
Spatial dependence of entanglement renormalization in XY model
Usman, M.; Ilyas, Asif; Khan, Khalid
2017-09-01
In this article, a comparative study of the renormalization of entanglement in one-, two- and three-dimensional space and its relation with quantum phase transition (QPT) near the critical point is presented by implementing the quantum renormalization group (QRG) method using numerical techniques. Adopting the Kadanoff's block approach, numerical results for the concurrence are obtained for the spin {-}1/2 XY model in all the spatial dimensions. The results show similar qualitative behavior as we move from the lower to the higher dimensions in space, but the number of iterations reduces for achieving the QPT in the thermodynamic limit. We find that in the two-dimensional and three-dimensional spin {-}1/2 XY model, maximum value of the concurrence reduce by the factor of 1 / n (n=2,3) with reference to the maximum value of one-dimensional case. Moreover, we study the scaling behavior and the entanglement exponent. We compare the results for one-, two- and three-dimensional cases and illustrate how the system evolves near the critical point.
Ising and Heisenberg models on ferrimagnetic AB sub 2 chains
Vitoriano, C; Raposo, E P
2002-01-01
We study the Ising and Heisenberg models on one-dimensional ferrimagnetic bipartite chains with the special AB sub 2 unit-cell topology and experimental motivation in inorganic and organic magnetic polymers. The spin-1/2 AB sub 2 Ising case is exactly solved in the presence of an external magnetic field. We also derive asymptotical low- and high-temperature limits of several thermodynamical quantities of the zero-field classical AB sub 2 Heisenberg model. Further, the quantum spin-1/2 AB sub 2 Heisenberg model in a field is studied using a mean-field approach.
Thermal entanglement of a spin-1/2 Ising-Heisenberg model on a symmetrical diamond chain
Ananikian, N. S.; Ananikyan, L. N.; Chakhmakhchyan, L. A.; Rojas, Onofre
2012-06-01
The entanglement quantum properties of a spin-1/2 Ising-Heisenberg model on a symmetrical diamond chain were analyzed. Due to the separable nature of the Ising-type exchange interactions between neighboring Heisenberg dimers, calculation of the entanglement can be performed exactly for each individual dimer. Pairwise thermal entanglement was studied in terms of the isotropic Ising-Heisenberg model and analytical expressions for the concurrence (as a measure of bipartite entanglement) were obtained. The effects of external magnetic field H and next-nearest neighbor interaction Jm between nodal Ising sites were considered. The ground state structure and entanglement properties of the system were studied in a wide range of coupling constant values. Various regimes with different values of ground state entanglement were revealed, depending on the relation between competing interaction strengths. Finally, some novel effects, such as the two-peak behavior of concurrence versus temperature and coexistence of phases with different values of magnetic entanglement, were observed.
DEFF Research Database (Denmark)
Gammelmark, Søren; Mølmer, Klaus
2011-01-01
the Ising phase transition. Physical systems with first-order phase transitions are natural candidates for metrology and calibration purposes, and we apply filter theory to show that the sensitivity of the physical system to temperature and external fields reaches the 1/N Heisenberg limit....
SU (N ) Heisenberg model with multicolumn representations
Okubo, Tsuyoshi; Harada, Kenji; Lou, Jie; Kawashima, Naoki
2015-10-01
The SU (N ) symmetric antiferromagnetic Heisenberg model with multicolumn representations on the two-dimensional square lattice is investigated by quantum Monte Carlo simulations. For the representation of a Young diagram with two columns, we confirm that a valence-bond solid (VBS) order appears as soon as the Néel order disappears at N =10 , indicating no intermediate phase. In the case of the representation with three columns, there is no evidence for either the Néel or the VBS ordering for N ≥15 . This is actually consistent with the large-N theory, which predicts that the VBS state immediately follows the Néel state, because the expected spontaneous order is too weak to be detected.
Yue, Yang; Zhang, Bo; Wang, Qiang; Lofland, Rob; O'Neil, Jason; Anderson, Jon
2016-03-21
Dual-polarization quadrature amplitude modulation (DP-QAM) is one of the feasible paths towards 100-Gb/s, 400-Gb/s and 1-Tb/s optical fiber communications systems. For DP-QAM transmitter, the time mismatch between the in-phase and quadrature (IQ) or x-polarized and y-polarized (XY) tributary channels is known as the IQ or XY skew. Large uncompensated IQ or XY skew can significantly degrade the optical fiber communications system performance. Sometimes, time-interleaved return-to-zero (RZ) DP signal is preferred with lower nonlinear polarization scattering induced penalty. In this work, detection and alignment of DP-QAM transmitter IQ and XY skews using reconfigurable interference is experimentally demonstrated. For IQ skew detection, a total dynamic range of 26.4 dB is achieved with ~1-dB power change for 0.5-ps skew from well alignment. For XY skew detection, it shows 23.2-dB dynamic range, and ~1.5-dB power change is achieved for 1-ps XY skew. Fast detection algorithm for arbitrary skew is also proposed and experimentally verified. The scheme is compatible with different modulation formats, flexible data sequences, and variable waveforms.
Periodic Driving at High Frequencies of an Impurity in the Isotropic XY Chain
Corsi, Livia; Genovese, Giuseppe
2017-09-01
We study the isotropic XY chain with a transverse magnetic field acting on a single site and analyse the long time behaviour of the time-dependent state of the system when a periodic perturbation drives the impurity. We find that for high frequencies the state approaches a periodic orbit synchronised with the forcing and provide the explicit rate of convergence to the asymptotics.
Beyond Uncertainty Heisenberg, Quantum Physics, and The Bomb
Cassidy, David C
2010-01-01
Award winning biographer revisits the controversial life of this well known German physicist to shed new light on troubling questions. What can we learn about the relationship of scientific research to state power from Heisenberg's role in Nazi Germany?
Three types magnetic moment distribution of nonlinear excitations in a Heisenberg helimagnet
Energy Technology Data Exchange (ETDEWEB)
Qi, Jian-Wen [School of Physics, Northwest University, Xi' an 710069 (China); Shaanxi Key Laboratory for Theoretical Physics Frontiers, Xi' an 710069 (China); Li, Zai-Dong [Department of Applied Physics, Hebei University of Technology, Tianjin 300401 (China); Yang, Zhan-Ying, E-mail: zyyang@nwu.edu.cn [School of Physics, Northwest University, Xi' an 710069 (China); Shaanxi Key Laboratory for Theoretical Physics Frontiers, Xi' an 710069 (China); Yang, Wen-Li [Shaanxi Key Laboratory for Theoretical Physics Frontiers, Xi' an 710069 (China); Institute of Modern Physics, Northwest University, Xi' an 710069 (China)
2017-06-15
Highlights: • Three different types of soliton excitations under the spin-wave background are demonstrated in spin chain system. • The magnetic moment distributions corresponding to these solitons are characterized in detail. • The formation mechanisms of those excitations are explained by the magnon density distribution. - Abstract: We study the nonlinear spin dynamics of an anisotropic Heisenberg helimagnet in a fourth-order integrable nonlinear Schrödinger equation. We demonstrate that there are three types of nonlinear spin excitations on a spin-wave background in the Heisenberg helimagnet, notably including anti-dark soliton, W-shaped soliton, and multi-peak soliton. The magnetic moment distribution that corresponds to each of these are characterized in detail. Additionally, the formation mechanism is clarified by the magnon density distribution.
Directory of Open Access Journals (Sweden)
Rafael Fabiano Machado Rosa
2008-11-01
ser rotineiramente avaliados em indivíduos com amenorréia primária. Dessa forma, haveria um reconhecimento mais precoce das pacientes 46,XY e, conseqüentemente, um adequado manejo clínico das mesmas.PURPOSE: to verify the prevalence and clinical characteristics of patients with primary amenorrhea and XY caryotype, evaluated in our Service, aiming at identifying findings which could help their recognition. METHODS: from January 1975 to November 2007, 104 patients with amenorrhea were evaluated. All the cases were analyzed by the caryotype by GTG bands. Among them, 21 (20.2% presented a XY 46 constitution. Nevertheless, two of them were excluded from the study, because of incomplete data in their patient's chart. Most of the 19 patients who formed the sample had been referred to us by the gynecology clinics (63.2%. Their ages varied from 16 to 41 years old (an average of 22.1. Data were collected about their family and previous history, physical examination and results of complementary exams and the information was taken into consideration to determine the diagnosis. RESULTS: the predominant diagnosis was resistance to androgens syndrome (n=12; 63.2%; five patients (25.3% presented XY pure gonadal dysgenesis (XY PGD, one (5.3% 17 alpha-hydroxylase deficiency, and one (5.3%, 5 alpha-reductase deficiency. Clinical findings frequently found in these patients included abnormal development of secondary sexual characters (n=19, uterine agenesia with a blind vagina (n=14, family history of amenorrhea (n=8, and palpable gonads in the inguinal canal (n=5. Two of them presented a history of inguinal hernia. Systemic arterial hypertension was only diagnosed in the patient with 17 alpha-hydroxylase deficiency, and gonadal malignization, in the one with XY PGD. CONCLUSIONS: the rate of patients with XY caryotype (20% was higher than the one described in the literature (3 to 11%. It is believed that this fact is related to the way patients are usually referred to our service
Lavery, Rowena; Lardenois, Aurélie; Ranc-Jianmotamedi, Fariba; Pauper, Eva; Gregoire, Elodie P; Vigier, Caroline; Moreilhon, Chimene; Primig, Michael; Chaboissier, Marie-Christine
2011-06-01
Gonadal differentiation is the first step of mammalian sex determination. The expression of the Y chromosomal testis determining factor Sry leads to up-regulation of the transcription factor Sox9 which promotes testis differentiation. Previous studies showed that Sox9 deficiency induces expression of ovarian markers in XY mutant fetal gonads before they die. To better understand the genome-wide transcriptional profile underlying this process we compared samples from XY Sf1:Cre(Tg/+); Sox9(flox/flox) mutant gonads in which Sox9 is ablated in Sertoli-precursor cells during early stages of gonad development to XX Sox9(flox/flox) ovaries and XY Sox9(flox/flox) testes at E13.5. We found a complex mRNA signature that indicates wide-spread transcriptional de-regulation and revealed for XY mutants at E13.5 an intermediate transcript profile between male and female gonads. However, XY Sf1:Cre(Tg/+); Sox9(flox/flox) mutant gonads develop as ovaries containing XY developing follicles at P0 but less frequently so than in XX control ovaries. Furthermore, we studied the extent to which developing XY mutant ovaries are able to mediate adult fertility and observed that XY oocytes from XY mutant ovaries are competent for fertilization; however, two thirds of them fail to develop beyond two-cell stage embryos. Taken together, we found that XY Sf1:Cre(Tg/+); Sox9(flox/flox) females are capable of producing viable offspring albeit at a reduced level. Copyright © 2011 Elsevier Inc. All rights reserved.
Etiological diagnosis of undervirilized male/XY disorder of sex development.
Atta, Irum; Ibrahim, Mohsina; Parkash, Arit; Lone, Saira Waqar; Khan, Yasir Naqi; Raza, Jamal
2014-10-01
To do clinical, hormonal and chromosomal analysis in undervirilized male / XY disorder of sex development and to make presumptive etiological diagnosis according to the new Disorder of Sex Development (DSD) classification system. Case series. Endocrine Unit at National Institute of Child Health, Karachi, Pakistan, from January 2007 to December 2012. Patients of suspected XY DSD / undervirilized male visiting endocrine clinic were enrolled in the study. Criteria suggested XY DSD include overt genital ambiguity, apparent female/male genitalia with inguinal/labial mass, apparent male genitalia with unilateral or bilateral non-palpable testes, micropenis and isolated hypospadias or with undescended testis. The older children who had delayed puberty were also evaluated with respect to DSD. As a part of evaluation of XY DSD, abdominopelvic ultrasound, karyotype, hormone measurement (testosterone, FSH, LH), FISH analysis with SRY probing, genitogram, laparoscopy, gonadal biopsy and HCG stimulation test were performed. Frequencies and percentages applied on categorical data whereas mean, median, standard deviation were calculated for continuous data. A total of 187 patients met the criteria of XY DSD. Age ranged from 1 month to 15 years, 55 (29.4%) presented in infancy, 104 (55.6%) between 1 and 10 years and 28 (15%) older than 10 years. Twenty five (13.4%) were raised as female and 162 as (86.6%) male. The main complaints were ambiguous genitalia, unilateral cryptorchidism, bilateral cryptorchidism, micropenis, delayed puberty, hypospadias, female like genitalia with gonads, inguinal mass. The karyotype was 46 XY in 183 (97.9%), 46 XX in 2 (1.1%), 47 XXY in 1 (0.5%), 45 X/46 XY in 1 (0.5%) patient. HCG stimulation test showed low testosterone response in 43 (23 %), high testosterone response in 62 (33.2%), partial testosterone response in 32 (17.1%) and normal testosterone response in 50 (26.7%). Genitogram was carried out in 86 (45.98%) patients. Presumptive etiological
Automated edge finishing using an active XY table
Loucks, Clifford S.; Starr, Gregory P.
1993-01-01
The disclosure is directed to an apparatus and method for automated edge finishing using hybrid position/force control of an XY table. The disclosure is particularly directed to learning the trajectory of the edge of a workpiece by "guarded moves". Machining is done by controllably moving the XY table, with the workpiece mounted thereon, along the learned trajectory with feedback from a force sensor. Other similar workpieces can be mounted, without a fixture on the XY table, located and the learned trajectory adjusted
Yang, Xiao-jun; Baleanu, Dumitru; Machado, J.A. Tenreiro
2013-01-01
In this paper, we discuss the mathematical aspects of the Heisenberg uncertainty principle within local fractional Fourier analysis. The Schrödinger equation and Heisenberg uncertainty principles are structured within local fractional operators.
Entanglement transfer via XXZ Heisenberg chain with DM interaction
Rafiee, M.; Soltani, M.; Mohammadi, H.; Mokhtari, H.
2011-08-01
The role of spin-orbit interaction arises from the Dzyaloshinskii-Moriya anisotropic antisymmetric interaction on the entanglement transfer via an antiferromagnetic XXZ Heisenberg chain is investigated. From symmetrical point of view the XXZ Hamiltonian with Dzyaloshinskii-Moriya interaction can be replaced by a modified XXZ Hamiltonian which is defined by a new exchange coupling constant and rotated Pauli operators. The modified coupling constant and the angle of rotations depend on the strength of Dzyaloshinskii-Moriya interaction. In this paper we study the dynamical behavior of the entanglement propagation through a system which is consist of a pair of maximally entangled spins coupled to one end of the chain. The calculations are performed for the ground state and the thermal state of the chain separately. In both cases the presence of this anisotropic interaction make our channel more efficient. We show for large values of the strength of this interaction a large family of XXZ chains becomes efficient quantum channels for whole values of anisotropy parameter in the region -2 ≤ Δ ≤ 2.
Deconfinement transitions in a generalised XY model
Serna, Pablo; Chalker, J. T.; Fendley, Paul
2017-10-01
We find the complete phase diagram of a generalised XY model that includes half-vortices. The model possesses superfluid, pair-superfluid and disordered phases, separated by Kosterlitz-Thouless (KT) transitions for both the half-vortices and ordinary vortices, as well as an Ising-type transition. There also occurs an unusual deconfining phase transition, where the disordered to superfluid transition is of Ising rather than KT type. We show by analytical arguments and extensive numerical simulations that there is a point in the phase diagram where the KT transition line meets the deconfining Ising phase transition. We find that the latter extends into the disordered phase not as a phase transition, but rather solely as a deconfinement transition. It is best understood in the dual height model, where on one side of the transition height steps are bound into pairs while on the other they are unbound. We also extend the phase diagram of the dual model, finding both O(2) loop model and antiferromagnetic Ising transitions.
Heisenberg in the atomic age science and the public sphere
Carson, Cathryn
2010-01-01
The end of the Second World War opened a new era for science in public life. Heisenberg in the Atomic Age explores the transformations of science's public presence in the postwar Federal Republic of Germany. It shows how Heisenberg's philosophical commentaries, circulating in the mass media, secured his role as science's public philosopher, and it reflects on his policy engagements and public political stands, which helped redefine the relationship between science and the state. With deep archival grounding, the book tracks Heisenberg's interactions with intellectuals from Heidegger to Habermas and political leaders from Adenauer to Brandt. It also traces his evolving statements about his wartime research on nuclear fission for the National Socialist regime. Working between the history of science and German history, the book's central theme is the place of scientific rationality in public life - after the atomic bomb, in the wake of the Third Reich.
Heisenberg scaling of imaging resolution by coherent enhancement
McConnell, Robert; Yoder, Theodore J; Bruzewicz, Colin D; Chuang, Isaac L; Chiaverini, John; Sage, Jeremy M
2016-01-01
Classical imaging works by scattering photons from an object to be imaged, and achieves resolution scaling as $1/\\sqrt{t}$, with $t$ the imaging time. By contrast, the laws of quantum mechanics allow one to utilize quantum coherence to obtain imaging resolution that can scale as quickly as $1/t$ -- the so-called "Heisenberg limit." However, ambiguities in the obtained signal often preclude taking full advantage of this quantum enhancement, while imaging techniques designed to be unambiguous often lose this optimal Heisenberg scaling. Here, we demonstrate an imaging technique which combines unambiguous detection of the target with Heisenberg scaling of the resolution. We also demonstrate a binary search algorithm which can efficiently locate a coherent target using the technique, resolving a target trapped ion to within 3% of the $1/e^2$ diameter of the excitation beam.
Multipartite geometric entanglement in finite size XY model
Energy Technology Data Exchange (ETDEWEB)
Blasone, Massimo; Dell' Anno, Fabio; De Siena, Silvio; Giampaolo, Salvatore Marco; Illuminati, Fabrizio, E-mail: blasone@sa.infn.i [Dipartimento di Matematica e Informatica, Universita degli Studi di Salerno, Via Ponte don Melillo, I-84084 Fisciano (Italy)
2009-06-01
We investigate the behavior of the multipartite entanglement in the finite size XY model by means of the hierarchical geometric measure of entanglement. By selecting specific components of the hierarchy, we study both global entanglement and genuinely multipartite entanglement.
[46 XY gonadal dysgenesis and dysgerminoma (author's transl)].
Ausín, J; Cavallé, L; Márquez, M; González-Merlo, J
1980-01-01
A patient with gonadal dysgenesis, cariotype 46 XY and female biotype is presented. The histological study confirmed the presence of a dysgerminoma in the left gonad. The features of the cases are discussed.
Gonadoblastoma in a patient with 46, XY complete gonadal dysgenesis.
Keskin, Melikşah; Savaş-Erdeve, Şenay; Kurnaz, Erdal; Çetinkaya, Semra; Karaman, Ayşe; Apaydın, Sema; Aycan, Zehra
2016-01-01
46, XY complete gonadal dysgenesis (Swyer syndrome) is a rare cause of 46, XY sexual development disorder. The patient presented to our clinic with absence of breast development and lack of periods at the age of 17 years. Her history and familial history involved no relevant conditions. She had Tanner stage 1 thelarche, and Tanner stage 2 pubic hair development with no axillary hair development. External genital structure appearance was consistent with female phenotype and the patient had no palpable gonad. The patient diagnosed as 46, XY complete gonadal dysgenesis after evaluation of laboratory analyses, radiological methods and karyotype. The Sexual Orientation and Gender Identity Committee concluded that gonadectomy should be performed. Histopathologic analysis demonstrated gonadoblastoma. Gonad structures should be sought laparoscopically and once diagnosed, streak gonads should be removed prophylactically in patients with 46, XY complete gonadal dysgenesis.
Fractional vortices in the XY model with $\\pi$ bonds
Kulkarni, R. V.; Almaas, E.; Fisher, K. D.; Stroud, D.
2000-01-01
We define a new set of excitations in the XY model which we call ``fractional vortices''. In the frustrated XY model containing $\\pi$ bonds, we make the ansatz that the ground state configurations can be characterized by pairs of oppositely charged fractional vortices. For a chain of $\\pi$ bonds, the ground state energy and the phase configurations calculated on the basis of this ansatz agree well with the results from direct numerical simulations. Finally, we discuss the possible connection ...
Heisenberg-Weyl algebra revisited: combinatorics of words and paths
Energy Technology Data Exchange (ETDEWEB)
Blasiak, P; Horzela, A [H. Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, ul. Radzikowskiego 152, PL 31342 Krakow (Poland); Duchamp, G H E [LIPN, UMR 7030, Universite Paris 13 - CNRS, 99 av. J-B Clement, F-93430 Villetaneuse (France); Penson, K A; Solomon, A I [Laboratoire de Physique Theorique de la Matiere Condensee, Universite Pierre et Marie Curie, CNRS UMR 7600, Tour 24-2ieme et., 4 pl. Jussieu, F 75252 Paris Cedex 05 (France)], E-mail: pawel.blasiak@ifj.edu.pl, E-mail: ghed@lipn-univ.paris13.fr, E-mail: andrzej.horzela@ifj.edu.pl, E-mail: penson@lptl.jussieu.fr, E-mail: a.i.solomon@open.ac.uk
2008-10-17
The Heisenberg-Weyl algebra, which underlies virtually all physical representations of quantum theory, is considered from the combinatorial point of view. We provide a concrete model of the algebra in terms of paths on a lattice with some decomposition rules. We also discuss the rook problem on the associated Ferrers board; this is related to the calculus in the normally ordered basis. From this starting point we explore combinatorial underpinning of the Heisenberg-Weyl algebra, which offers novel perspectives, methods and applications.
Energy Technology Data Exchange (ETDEWEB)
Restrepo-Parra, E., E-mail: erestrepopa@unal.edu.c [Departamento de Fisica y Quimica, Universidad Nacional de Colombia-Sede Manizales, A.A. 127 Manizales (Colombia); Salazar-Enriquez, C.D.; Londono-Navarro, J.; Jurado, J.F. [Departamento de Fisica y Quimica, Universidad Nacional de Colombia-Sede Manizales, A.A. 127 Manizales (Colombia); Restrepo, J. [Grupo de Magnetismo y Simulacion, Instituto de Fisica. Universidad de Antioquia, A.A. 1226, Medellin (Colombia)
2011-06-15
This work presents a critical temperature study of La{sub 1-x}Ca{sub x}MnO{sub 3} manganites in bulk by means of Monte Carlo method thermal activated magnetic properties. The analysis was carried out for stoichiometries in the range of 0{<=}x{<=}1. The model is based on a three-dimensional classical Heisenberg-Hamiltonian involving the presence of Mn{sup 3+eg}, Mn{sup 3+eg'} and Mn{sup 4+} ions, and their nearest neighbor interaction. For this modeling, simple cubic lattice samples of size L{sup 3}, with L=6, 15 and 30 were used. The values of exchange parameters were determined by using LaMnO{sub 3} (x=0), La{sub 0.5}Ca{sub 0.5}MnO{sub 3} and CaMnO{sub 3} (x=1) phases. Relationships between exchange parameters and anisotropy constants for different hole densities were found. Results of transition temperatures for each phase showed good agreement with experimental reports, especially for L=30 and L{yields}{infinity}. - Research highlights: Stoichiometry influences the exchange interaction between magnetic ions. Charge and orbital ordering depend on the stoichiometry. LCMO magnetic phase diagram has a great variety of magnetic states.
Entanglement in the quantum one-dimensional integer spin S Heisenberg antiferromagnet
Lima, L. S.
2017-10-01
We use the modified spin wave theory of Takahashi to study the entanglement entropy in the quantum one-dimensional integer spin Heisenberg antiferromagnet. We calculate the entanglement entropy of this spin system that is well known to be a quantum wire, in the classical limit (N → ∞). We obtain a decreasing the entanglement entropy with the temperature and we obtain none change in the entanglement in the point Δ = 1 at T = 0 where the system presents a quantum phase transition from a gapless phase in the spectrum Δ < 1 to a gapped phase Δ ≥ 1.
Engineering Ising-XY spin-models in a triangular lattice using tunable artificial gauge fields
Struck, J.; Weinberg, M.; Ölschläger, C.; Windpassinger, P.; Simonet, J.; Sengstock, K.; Höppner, R.; Hauke, P.; Eckardt, A.; Lewenstein, M.; Mathey, L.
2013-11-01
Magnetism plays a key role in modern science and technology, but still many open questions arise from the interplay of magnetic many-body interactions. Deeper insight into complex magnetic behaviour and the nature of magnetic phase transitions can be obtained from, for example, model systems of coupled XY and Ising spins. Here, we report on the experimental realization of such a coupled system with ultracold atoms in triangular optical lattices. This is accomplished by imposing an artificial gauge field on the neutral atoms, which acts on them as a magnetic field does on charged particles. As a result, the atoms show persistent circular currents, the direction of which provides an Ising variable. On this, the tunable staggered gauge field, generated by a periodic driving of the lattice, acts as a longitudinal field. Further, the superfluid ground state presents strong analogies with the paradigm example of the fully frustrated XY model on a triangular lattice.
Linear-Optical Generation of Eigenstates of the Two-Site XY Model
Directory of Open Access Journals (Sweden)
Stefanie Barz
2015-04-01
Full Text Available Much of the anticipation accompanying the development of a quantum computer relates to its application to simulating dynamics of another quantum system of interest. Here, we study the building blocks for simulating quantum spin systems with linear optics. We experimentally generate the eigenstates of the XY Hamiltonian under an external magnetic field. The implemented quantum circuit consists of two cnot gates, which are realized experimentally by harnessing entanglement from a photon source and applying a cphase gate. We tune the ratio of coupling constants and the magnetic field by changing local parameters. This implementation of the XY model using linear quantum optics might open the door to future studies of quenching dynamics using linear optics.
Nomura, Risa; Miyai, Kentaro; Okada, Michiyo; Kajiwara, Michiko; Ono, Makoto; Ogata, Tsutomu; Onishi, Iichiro; Sato, Mana; Sekine, Masaki; Akashi, Takumi; Mizutani, Shuki; Kashimada, Kenichi
2015-01-01
In 45,X/46,XY DSDs, the proportion of the two cell lineages is uneven in different organs and tissues, and 45,X and 46,XY cells can be found throughout the body. The gonadal development of 45,X/46,XY patients depends on the population of 46,XY cells in the gonads and the clinical features are variable. We had a 45,X/46,XY DSD patient whose 46,XY population in peripheral blood was extremely low, less than 0.2%, and was not detected by FISH analysis. However, the patient showed bilateral testicular development and more than 50% of the cells in the gonads had the 46,XY karyotype. This case suggests that a drastically imbalanced distribution could occur in 45,X/46,XY DSD cases.
Poláková, M; Alexander, D; Sulc, J; Zetová, L; Vlk, R; Křepelová, A; Zantová, D
2013-11-01
Summary review and a case report. GEST IVF, Centre of Reproductive Medicine, Prague. In scientific literature there two syndrome have been described in the presence of pure 46,XY karyotype when an individual is phenotypically and psychosexually identified as a woman. Androgen insensitivity syndrome (AIS) and pure gonadal dysgenesis XY (GD XY, Swyer syndrome). Thanks to the presence of a uterus in Swyer syndrome we can treat this type of sterility with donated oocytes. The paper describes both syndromes from prenatal, genetical, endocrinological, oncological, reproductive and perinatological points of view. A case study concerning a patient with pure gonadal dysgenesis XY, who successfully became pregnant through a donated oocytes programme, is also described. The pregnancy progressed physiologically, and a healthy boy, 3820g/52cm, was delivered in term by ceasarean section. In world scientific literature at least fifteen successful pregnancies with pure gonadal dysgenesis XY have been described. In spite of the expectation of diminished uterine capacity, children are born to term with a normal delivery weight. This article should be considered as a summary of all actual knowledge about these patients. This article should be available and usefull for clinicians who come across XY females. The case study provides evidence that even an individual with male genetic gender can be pregnant and deliver a healthy child.
Suh, B J
2000-01-01
A comprehensive analysis of the sup 3 sup 5 Cl nuclear magnetic resonance (NMR) relaxation data in Sr sub 2 CuO sub 2 Cl sub 2 single crystals is presented. Both the spin-lattice relaxation rate, T sub 1 sup - sup 1 (=2W), and the spin-spin relaxation rate, T sub 2 sup - sup 1 , show a crossover of the spin dimensionality well above the Neel temperature T sub N. The crossover is due to easy-plane anisotropy and is apparently signaled by the partial suppression of the Cu sup 2 sup + spin fluctuations along the tetragonal c-axis. By analyzing 2W for H ll c in terms of the critical behavior of the spin correlation length, we estimate the temperature for the crossover of the Cu sup 2 sup + spin correlations from Heisenberg to XY-like behavior to be T approx =290 K.
Chiral hedgehog textures in 2D XY-like ordered domains
Loh, Kok-Kiong; Kraus, Isabelle; Meyer, Robert B.
1999-01-01
The textures associated with a point defect centered in a circular domain of a thin film with XY-like ordering have been analyzed. The family of equilibrium textures, both stable and metastable, can be classified by a new radial topological number in addition to the winding number of the defect. Chiral textures are supported in an achiral system as a result of spontaneously broken chiral symmetry. Among these chiral textures, our theoretical analysis accurately describes two categories of rec...
A Poisson type formula for Hardy classes on Heisenberg's group
Directory of Open Access Journals (Sweden)
Lopushansky O.V.
2010-06-01
Full Text Available The Hardy type class of complex functions with infinite many variables defined on the Schrodinger irreducible unitary orbit of reduced Heisenberg group, generated by the Gauss density, is investigated. A Poisson integral type formula for their analytic extensions on an open ball is established. Taylor coefficients for analytic extensions are described by the associatedsymmetric Fock space.
Hysteresis behavior of the anisotropic quantum Heisenberg model
Akıncı, Ümit
2012-01-01
The effect of the anisotropy in the exchange interaction on the hysteresis loops within the anisotropic quantum Heisenberg model has been investigated with the effective field theory for two spin cluster. Particular attention has been devoted on the behavior of the hysteresis loop area, coercive field and remanent magnetization with the anisotropy in the exchange interaction for both ferromagnetic and paramagnetic phases.
Generalized Heisenberg algebra coherent states for Power-law potentials
Berrada, Kamal; Baz, Morad El; Hassouni, Yassine
2010-01-01
Coherent states for power-law potentials are constructed using generalized Heisenberg algabras. Klauder's minimal set of conditions required to obtain coherent states are satisfied. The statistical properties of these states are investigated through the evaluation of the Mandel's parameter. It is shown that these coherent states are useful for describing the states of real and ideal lasers.
A simple and powerful XY-Type current monitor for 30 MeV IPEN/CNEN-SP cyclotron
Energy Technology Data Exchange (ETDEWEB)
Barcellos, Henrique; Matsuda, Hylton; Sumyia, Luiz Carlos do A.; Junqueira, Fernando de C.; Costa, Osvaldo L. da, E-mail: hbolivei@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)
2017-11-01
A water-cooled XY-type current monitor was designed and built in the Cyclotrons Laboratory of the Nuclear and Energy Research Institute (IPEN). It is a very simple design and easily adaptable to the cyclotron beam lines. Tests were done demonstrating to be an instrument of great assistance in proton beam position along beam transport line and target port. Nowadays the XY-type current monitor has been widely used in {sup 18}F-FDG routine productions, employing irradiation system which were originally designed for productions on 18 MeV cyclotron accelerator only, however, applying the XY-type current monitor the target port may be exchanged between the 30 MeV and 18 MeV cyclotrons and the observed results are in perfect agreement with expected. (author)
Fragile fate of driven-dissipative XY phase in two dimensions
Maghrebi, Mohammad F.
2017-11-01
Driven-dissipative systems define a broad class of nonequilibrium systems where an external drive (e.g., laser) competes with a dissipative environment. The steady state of dynamics is generically distinct from a thermal state characteristic of equilibrium. As a representative example, a driven-dissipative system with a continuous symmetry is generically disordered in two dimensions in contrast with the well-known algebraic order in equilibrium XY phases. In this paper, we study a two-dimensional driven-dissipative model of weakly interacting bosons with a continuous U (1 ) symmetry. Our aim is twofold: First, we show that an effectively equilibrium XY phase emerges despite the driven nature of the model, and that it is protected by a natural Z2 symmetry of the dynamics. Second, we argue that this phase is unstable against symmetry-breaking perturbations as well as static disorder, whose mechanism in most cases has no analog in equilibrium. In the language of renormalization group theory, we find that, outside equilibrium, there are more relevant directions away from the XY phase.
Molecular heterogeneity of XY sex reversal in horses.
Raudsepp, T; Durkin, K; Lear, T L; Das, P J; Avila, F; Kachroo, P; Chowdhary, B P
2010-12-01
Male-to-female 64,XY sex reversal is a frequently reported chromosome abnormality in horses. Despite this, the molecular causes of the condition are as yet poorly understood. This is partially because only limited molecular information is available for the horse Y chromosome (ECAY). Here, we used the recently developed ECAY map and carried out the first comprehensive study of the Y chromosome in XY mares (n=18). The integrity of the ECAY in XY females was studied by FISH and PCR using markers evenly distributed along the euchromatic region. The results showed that the XY sex reversal condition in horses has two molecularly distinct forms: (i) a Y-linked form that is characterized by Y chromosome deletions and (ii) a non-Y-linked form where the Y chromosome of affected females is molecularly the same as in normal males. Further analysis of the Y-linked form (13 cases) showed that the condition is molecularly heterogeneous: the smallest deletions spanned about 21 kb, while the largest involved the entire euchromatic region. Regardless of the size, all deletions included the SRY gene. We show that the deletions were likely caused by inter-chromatid recombination events between repeated sequences in ECAY. Further, we hypothesize that the occurrence of SRY-negative XY females in some species (horse, human) but not in others (pig, dog) is because of differences in the organization of the Y chromosome. Finally, in contrast to the Y-linked SRY-negative form of equine XY sex reversal, the molecular causes of SRY-positive XY mares (5 cases) remain as yet undefined. © 2010 The Authors, Journal compilation © 2010 Stichting International Foundation for Animal Genetics.
Pairwise entanglement of two impurities in the XY model
Energy Technology Data Exchange (ETDEWEB)
Sun, Yi [Department of Physics, Changji University, Changji, 830011 (China); State Key Laboratory of Crystal Materials, Shandong University, Jinan, 250100 (China); Huang, Xuchu, E-mail: hxuchu@163.com [Department of Physics, Changji University, Changji, 830011 (China); Min, Guanghui [Materials Science and Engineering Institute, Shandong University, Jinan, 250100 (China)
2017-01-30
We propose a general method to solve the anisotropic XY model with two impurities on the period boundary condition. On the basis of exact solution, we discuss the impurity excitations in detail. The results indicate that the critical behaviors of the system near the critical point are closely related to the particle excitations. We investigate the quantum phase transition and the pairwise entanglement of the nearest-neighbors impurities, and find that the singular behaviors of pairwise entanglement near the critical point are naturally derived from the competition between impurity excitation and normal fermion excitation. When the two impurities are separated at certain distance, the pairwise entanglements oscillate with the variation of the distance, and the oscillations diminish with the increase of the distance. The couple interaction and anisotropy of impurity both can control the pairwise entanglement, however, this effects strongly depend on the order state of the system. - Highlights: • By introducing a proper displacement quantity of impurity, this method can be applied in complex spin model. • The pairwise entanglement of impurities can be controlled by the coupling and anisotropy of impurity. • The singular behaviors of the pairwise entanglement are closely related to the particle excitation.
Heisenberg's roadmap guides our journey to the small cognitive world of Drosophila.
Guo, Aike; Zhang, Ke; Peng, Yueqing; Xi, Wang
2009-01-01
Professor Martin Heisenberg is one of the pioneers in the exploration of neuroethology. With his inspiration and earnest help, we employed the fruitfly as a model system to investigate the underlying neural mechanism of cognitive behaviors. Here, we recalled the help from Martin in the early years and introduced some findings from our lab about visual cognition behaviors in Drosophila, such as decision making, selective attention, and experience-dependent visual pattern recognition. From the results so far, the circuit composed of mushroom bodies, central complex, and dopaminergic neurons may play an essential role in these behaviors.
XMM-Newton Observation of the Intermediate Polar XY Ari
Zengin Camurdan, Dicle; Balman, Solen; Burwitz, Vadim
2016-07-01
XY Ari is a rare Intermediate Polar which shows deep X-ray eclipses and has no optical counterpart due to the high visual extinction. We present results from a detailed analysis of an unpublished archival observation using XMM-Newton EPIC-pn and MOS data covering to more than five orbital periods in a quiescent state of XY Ari. The X-ray orbital modulation and spin pulse variations were investigated in 0.2-10 keV energy band and also in different energy bands (i.e. 0.3-1.5, 1.6-3.0, 3.1-10 keV). The EPIC light curves folded at the spin phases show a double peak profile as expected from double pole accretion. However, a detailed analysis showed that the relative peak heights of the spin profiles, corresponding to different time intervals, vary during the entire observation which may be a result of small accretion rate differences or variable scattering from the weaker pole. We modeled the time-averaged spectrum with single- and multi-temperature optically thin thermal plasma emission (e.g. MEKAL APEC/VAPEC, CEVMKL, MKCFLOW/VMKCFLOW) in XSPEC to derive spectral parameters. The simultaneously fitted EPIC spectra with a double MEKALs model yield plasma temperatures of kT_{MEKAL}=39-44 keV and kT_{MEKAL}=0.3-2.21 keV with a solar metal abundance of 0.52-71 (for higher MEKAL temperature). We find an intrinsic, partial covering absorption about N _{H}=2.9-5.5x10 ^{22} cm ^{-2}. In addition, Gaussian lines at the Fe line energies 6.4 and 6.7 keV, were also included in the fit. We will discuss different model fits and the accretion geometry of the system. The X-ray luminosity of the source is ˜2x10 ^{32} erg/sec in the 0.2-10.0 keV range assuming a 270 pc distance.
Phase boundaries in the ternary (Bi0.5Na0.5TiO3)x(BaTiO3)y(SrTiO3)1-x-y system
Marlton, Frederick; Standard, Owen; Kimpton, Justin A.; Daniels, John E.
2017-11-01
The phase boundaries within (Bi0.5Na0.5TiO3)x(BaTiO3)y(SrTiO3)1-x-y with x ≥ 0.68 have been outlined. This was achieved using a combinatorial sample fabrication method and scanning synchrotron X-ray diffraction to rapidly characterise crystallographic structures over a large region of phase space. A parametric refinement method was used to clearly outline the phase boundaries as a function of the composition. The pseudo-cubic structure from the high strain non-ergodic Bi0.5Na0.5TiO3-BaTiO3 composition extends into the phase diagram with doping of SrTiO3, with regions of tetragonal and rhombohedral in the BaTiO3 and Bi0.5Na0.5TiO3 ends, respectively. This information can be used in conjunction with further compositional modifications to develop high strain piezoceramics that make use of electric-field-induced phase transformations and further understand the mechanisms in ergodic vs non-ergodic relaxors.
Scherer, Daniel D.; Scherer, Michael M.; Khaliullin, Giniyat; Honerkamp, Carsten; Rosenow, Bernd
2014-07-01
We study the quantum many-body instabilities of the t-JK-JH Kitaev-Heisenberg Hamiltonian on the honeycomb lattice as a minimal model for a doped spin-orbit Mott insulator. This spin-1/2 model is believed to describe the magnetic properties of the layered transition-metal oxide Na2IrO3. We determine the ground state of the system with finite charge-carrier density from the functional renormalization group (fRG) for correlated fermionic systems. To this end, we derive fRG flow equations adapted to the lack of full spin-rotational invariance in the fermionic interactions, here represented by the highly frustrated and anisotropic Kitaev exchange term. Additionally employing a set of the Ward identities for the Kitaev-Heisenberg model, the numerical solution of the flow equations suggests a rich phase diagram emerging upon doping charge carriers into the ground-state manifold (Z2 quantum spin liquids and magnetically ordered phases). We corroborate superconducting triplet p-wave instabilities driven by ferromagnetic exchange and various singlet pairing phases. For filling δ >1/4, the p-wave pairing gives rise to a topological state with protected Majorana edge modes. For antiferromagnetic Kitaev and ferromagnetic Heisenberg exchanges, we obtain bond-order instabilities at van Hove filling supported by nesting and density-of-states enhancement, yielding dimerization patterns of the electronic degrees of freedom on the honeycomb lattice. Further, our flow equations are applicable to a wider class of model Hamiltonians.
Sliwa, Katrina
The quantum back-action of the measurement apparatus arising from the Heisenberg uncertainty principle is both a fascinating phenomenon and a powerful way to apply operations on quantum systems. Unfortunately, there are other effects which may overwhelm the Heisenberg back-action. This thesis focuses on two effects arising in the dispersive measurement of superconducting qubits made with two ultra-low-noise parametric amplifiers, the Josephson bifurcation amplifier (JBA) and the Josephson parametric converter (JPC). The first effect is qubit dephasing due to excess photons in the cavity coming from rogue radiation emitted by the first amplifier stage toward the system under study. This problem arises primarily in measurements made with the JBA, where a strong resonant pump tone is traditionally used to provide the energy for amplification. Replacing the single strong pump tone with two detuned pump tones minimized this dephasing to the point where the Heisenberg back-action of measurements made with the JBA could be observed. The second effect is reduced measurement efficiency arising from losses between the qubit and the parametric amplifier. Most commonly used parametric amplifiers operate in reflection, requiring additional lossy, magnetic elements known as circulators both to separate input from output, and to protect the qubits from dephasing due to the amplified reflected signal. This work presents two alternative directional elements, the Josephson circulator, which is both theoretically loss-less and does not rely upon the strong magnetic fields needed for traditional circulators, and the Josephson directional amplifier which does not send any amplified signal back toward the qubit. Both of these elements achieve directionality by interfering multiple parametric processes inside a single JPC, allowing for in-situ switching between the two modes of operation. This brings valuable experimental flexibility, and also makes these devices strong candidates for
Nearly Deconfined Spinon Excitations in the Square-Lattice Spin-1/2 Heisenberg Antiferromagnet
Directory of Open Access Journals (Sweden)
Hui Shao
2017-12-01
Full Text Available We study the spin-excitation spectrum (dynamic structure factor of the spin-1/2 square-lattice Heisenberg antiferromagnet and an extended model (the J-Q model including four-spin interactions Q in addition to the Heisenberg exchange J. Using an improved method for stochastic analytic continuation of imaginary-time correlation functions computed with quantum Monte Carlo simulations, we can treat the sharp (δ-function contribution to the structure factor expected from spin-wave (magnon excitations, in addition to resolving a continuum above the magnon energy. Spectra for the Heisenberg model are in excellent agreement with recent neutron-scattering experiments on Cu(DCOO_{2}·4D_{2}O, where a broad spectral-weight continuum at wave vector q=(π,0 was interpreted as deconfined spinons, i.e., fractional excitations carrying half of the spin of a magnon. Our results at (π,0 show a similar reduction of the magnon weight and a large continuum, while the continuum is much smaller at q=(π/2,π/2 (as also seen experimentally. We further investigate the reasons for the small magnon weight at (π,0 and the nature of the corresponding excitation by studying the evolution of the spectral functions in the J-Q model. Upon turning on the Q interaction, we observe a rapid reduction of the magnon weight to zero, well before the system undergoes a deconfined quantum phase transition into a nonmagnetic spontaneously dimerized state. Based on these results, we reinterpret the picture of deconfined spinons at (π,0 in the experiments as nearly deconfined spinons—a precursor to deconfined quantum criticality. To further elucidate the picture of a fragile (π,0-magnon pole in the Heisenberg model and its depletion in the J-Q model, we introduce an effective model of the excitations in which a magnon can split into two spinons that do not separate but fluctuate in and out of the magnon space (in analogy to the resonance between a photon and a particle-hole pair in
Anomalous behavior of the energy gap in the one-dimensional quantum XY model.
Okuyama, Manaka; Yamanaka, Yuuki; Nishimori, Hidetoshi; Rams, Marek M
2015-11-01
We reexamine the well-studied one-dimensional spin-1/2 XY model to reveal its nontrivial energy spectrum, in particular the energy gap between the ground state and the first excited state. In the case of the isotropic XY model, the XX model, the gap behaves very irregularly as a function of the system size at a second order transition point. This is in stark contrast to the usual power-law decay of the gap and is reminiscent of the similar behavior at the first order phase transition in the infinite-range quantum XY model. The gap also shows nontrivial oscillatory behavior for the phase transitions in the anisotropic model in the incommensurate phase. We observe a close relation between this anomalous behavior of the gap and the correlation functions. These results, those for the isotropic case in particular, are important from the viewpoint of quantum annealing where the efficiency of computation is strongly affected by the size dependence of the energy gap.
Occurrence of Gonadoblastoma in Patients with 45,X/46,XY Mosaicism.
Dendrinos, Melina L; Smorgick, Noam; Marsh, Courtney A; Smith, Yolanda R; Quint, Elisabeth H
2015-06-01
To estimate the overall frequency of gonadal tumors in patients with 45,X/46,XY mosaicism who underwent gonadectomy and to determine whether the degree of external masculinization or the location of gonads were associated with the presence of gonadal tumor. Retrospective study of patients with karyotype of 45,X/46,XY or variant who received care at the study institution between 1995 and 2012. University of Michigan Health System (Ann Arbor, Michigan), a tertiary care academic center. Sixteen patients with karyotype of 45,X/46,XY who underwent gonadectomy. None. Presence of pathology-confirmed gonadal tumor. In patients who underwent bilateral gonadectomy, gonadoblastomas were detected in 36.4% (4 of 11), and all were identified in patients with normal female external genitalia (4 of 8 [50.0%]). Abdominal gonads were associated with a nonsignificant increase in rate of gonadal tumor compared with inguinal or scrotal gonads. No malignant tumors were identified. The overall rate of gonadoblastoma was higher than previously reported. The high rate of gonadoblastoma in patients with female external genitalia and the lack of gonadal function support continuing the standard of care of practice of prophylactic gonadectomy in this patient population. Copyright © 2015 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.
Mutations of the SRY-responsive enhancer of SOX9 are uncommon in XY gonadal dysgenesis.
Georg, I; Bagheri-Fam, S; Knower, K C; Wieacker, P; Scherer, Gerd; Harley, V R
2010-01-01
During mouse sex determination, SRY upregulates the core testis-specific enhancer of Sox9, TESCO. Mutations in human SRY are found in one third of cases with XY pure gonadal dysgenesis (XY GD; Swyer syndrome), while two thirds remain unexplained. Heterozygous SOX9 mutations can cause XY GD in association with the skeletal malformation syndrome campomelic dysplasia. We hypothesized that human TESCO mutations could cause isolated XY GD. Sixty-six XY GD cases with an intact SRY were analyzed for TESCO point mutations or deletions. No mutations were identified. We conclude that TESCO mutations are not a common cause of XY GD. Copyright © 2010 S. Karger AG, Basel.
Global quantum discord and quantum phase transition in XY model
Energy Technology Data Exchange (ETDEWEB)
Liu, Si-Yuan [Institute of Modern Physics, Northwest University, Xian 710069 (China); Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Zhang, Yu-Ran, E-mail: yrzhang@iphy.ac.cn [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Yang, Wen-Li, E-mail: wlyang@nwu.edu.cn [Institute of Modern Physics, Northwest University, Xian 710069 (China); Fan, Heng, E-mail: hfan@iphy.ac.cn [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100190 (China); Institute of Modern Physics, Northwest University, Xian 710069 (China)
2015-11-15
We study the relationship between the behavior of global quantum correlations and quantum phase transitions in XY model. We find that the two kinds of phase transitions in the studied model can be characterized by the features of global quantum discord (GQD) and the corresponding quantum correlations. We demonstrate that the maximum of the sum of all the nearest neighbor bipartite GQDs is effective and accurate for signaling the Ising quantum phase transition, in contrast, the sudden change of GQD is very suitable for characterizing another phase transition in the XY model. This may shed lights on the study of properties of quantum correlations in different quantum phases.
Non-Arrhenius relaxation of the Heisenberg model with dipolar and anisotropic interactions
Energy Technology Data Exchange (ETDEWEB)
Diaz-Mendez, Rogelio, E-mail: rogelio@electrica.cujae.edu.cu [Nanophysics Group, Department of Physics, Electric Engineering Faculty, CUJAE, ave 114 final, La Habana (Cuba); ' Henri Poincare' Group of Complex Systems, Physics Faculty, University of Havana, La Habana, CP 10400 (Cuba); Mulet, Roberto [' Henri Poincare' Group of Complex Systems, Physics Faculty, University of Havana, La Habana, CP 10400 (Cuba); Department of Theoretical Physics, Physics Faculty, University of Havana, La Habana, CP 10400 (Cuba)
2012-01-15
The dynamical properties of a 2D Heisenberg model with dipolar interactions and perpendicular anisotropy are studied using Monte Carlo simulations in two different ordered regions of the equilibrium phase diagram. We find a temperature defining a dynamical transition below which the relaxation suddenly slows down and the system apart from the typical Arrhenius relaxation to a Vogel-Fulcher-Tamann law. This anomalous behavior is observed in the scaling of the magnetic relaxation and may eventually lead to a freezing of the system. Through the analysis of the domain structures we explain this behavior in terms of the domains dynamics. Moreover, we calculate the energy barriers distribution obtained from the data of the magnetic viscosity. Its shape supports our comprehension of both, the Vogel-Fulcher-Tamann dynamical slowing down and the freezing mechanism. - Highlights: > We make Monte Carlo simulations in a dipolar Heisenberg model with anisotropy. > We find a dynamical transition temperature below which the relaxation is VFT-like. > An interpretation is done by analyzing the domains structure and energy barriers.
Emergent chiral spin liquid: fractional quantum Hall effect in a kagome Heisenberg model.
Gong, Shou-Shu; Zhu, Wei; Sheng, D N
2014-09-10
The fractional quantum Hall effect (FQHE) realized in two-dimensional electron systems under a magnetic field is one of the most remarkable discoveries in condensed matter physics. Interestingly, it has been proposed that FQHE can also emerge in time-reversal invariant spin systems, known as the chiral spin liquid (CSL) characterized by the topological order and the emerging of the fractionalized quasiparticles. A CSL can naturally lead to the exotic superconductivity originating from the condense of anyonic quasiparticles. Although CSL was highly sought after for more than twenty years, it had never been found in a spin isotropic Heisenberg model or related materials. By developing a density-matrix renormalization group based method for adiabatically inserting flux, we discover a FQHE in a spin-½ isotropic kagome Heisenberg model. We identify this FQHE state as the long-sought CSL with a uniform chiral order spontaneously breaking time reversal symmetry, which is uniquely characterized by the half-integer quantized topological Chern number protected by a robust excitation gap. The CSL is found to be at the neighbor of the previously identified Z2 spin liquid, which may lead to an exotic quantum phase transition between two gapped topological spin liquids.
Entanglement in a Spin-$s$ Antiferromagnetic Heisenberg Chain
Hao, Xiang; Zhu, Shiqun
2006-01-01
The entanglement in a general Heisenberg antiferromagnetic chain of arbitrary spin-$s$ is investigated. The entanglement is witnessed by the thermal energy which equals to the minimum energy of any separable state. There is a characteristic temperature below that an entangled thermal state exists. The characteristic temperature for thermal entanglement is increased with spin $s$. When the total number of lattice is increased, the characteristic temperature decreases and then approaches a cons...
Graph model of the Heisenberg-Weyl algebra
Energy Technology Data Exchange (ETDEWEB)
Blasiak, P; Horzela, A [H. Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences ul. Radzikowskiego 152, PL 31342 Krakow (Poland); Duchamp, G H E [Universite Paris-Nord, LIPN, CNRS UMR 7030 99 Av. J.-B. Clement, F-93430 Villetaneuse (France); Penson, K A; Solomon, A I, E-mail: pawel.blasiak@ifj.edu.p, E-mail: ghed@lipn-univ.paris13.f, E-mail: andrzej.horzela@ifj.edu.p, E-mail: penson@lptmc.jussieu.f, E-mail: a.i.solomon@open.ac.u [Universite Pierre et Marie Curie, LPTMC, CNRS UMR 7600 Tour 24 - 2ieme et., 4 pl. Jussieu, F 75252 Paris Cedex 05 (France)
2010-03-01
We consider an algebraic formulation of Quantum Theory and develop a combinatorial model of the Heisenberg-Weyl algebra structure. It is shown that by lifting this structure to the richer algebra of graph operator calculus, we gain a simple interpretation involving, for example, the natural composition of graphs. This provides a deeper insight into the algebraic structure of Quantum Theory and sheds light on the intrinsic combinatorial underpinning of its abstract formalism.
X-ray excited optical luminescence studies on the system BaXY (X,Y ...
Indian Academy of Sciences (India)
For the fluorobromide, the undoped salt gave a broad luminescence peak located at 440 nm, while the ... The undoped BaFBr acquired a bluish pink colour, and the doped salt displayed a pink colour after the .... lived excited state, before decay, allows momentum conservation by the interaction with the lattice, so that the ...
Improved quantum circuit modelling based on Heisenberg representation
Lee, Y. H.; Khalil-Hani, M.; Marsono, M. N.
2018-02-01
Heisenberg model allows a more compact representation of certain quantum states and enables efficient modelling of stabilizer gates operation and single-qubit measurement in computational basis on classical computers. Since generic quantum circuit modelling appears intractable on classical computers, the Heisenberg representation that makes the modelling process at least practical for certain circuits is crucial. This paper proposes efficient algorithms to facilitate accurate global phase maintenance for both stabilizer and non-stabilizer gates application that play a vital role in the stabilizer frames data structure, which is based on the Heisenberg representation. The proposed algorithms are critical as maintaining global phase involves compute-intensive operations that are necessary for the modelling of each quantum gate. In addition, the proposed work overcomes the limitations of prior work where the phase factors due to non-stabilizer gates application was not taken into consideration. The verification of the proposed algorithms is made against the golden reference model that is constructed based on the conventional state vector approach.
X-Y plotter adapter developed for SDS-930 computer
Robertson, J. B.
1968-01-01
Graphical Display Adapter provides a real time display for digital computerized experiments. This display uses a memory oscilloscope which records a single trace until erased. It is a small hardware unit which interfaces with the J-box feature of the SDS-930 computer to either an X-Y plotter or a memory oscilloscope.
A healthy, female chimera with 46,XX/46,XY karyotype.
Binkhorst, M.; Leeuw, N. de; Otten, B.J.
2009-01-01
We report a healthy and unambiguously female newborn, whose phenotypic sex contradicted the expected male sex based on previously performed prenatal cytogenetic analysis. Both 46,XX and 46,XY cells were detected in a villus sample, the former having been attributed to maternal cell contamination.
Conducting-angle-based percolation in the XY model
Wang, Y.; Guo, W.; Nienhuis, B.; Blöte, H.W.J.
2010-01-01
We define a percolation problem on the basis of spin configurations of the two-dimensional XY model. Neighboring spins belong to the same percolation cluster if their orientations differ less than a certain threshold called the conducting angle. The percolation properties of this model are studied
First-order transitions for some generalized XY models
Enter, Aernout C.D. van; Romano, Silvano; Zagrebnov, Valentin A.
2006-01-01
In this letter we demonstrate the occurrence of first-order transitions in temperature for some recently introduced generalized XY models, and also point out the connection between them and annealed site-diluted (lattice-gas) continuous-spin models.
The fate of neo-XY chromosomes of grasshoppers
Indian Academy of Sciences (India)
2011-12-07
Dec 7, 2011 ... acridid grasshopper Podisma pedestris that has two chro- mosomal forms: a standard X0/XX and a ... that, although neo-XY chromosomes of grasshoppers may be a useful model to explain the spread of a ... repetitive DNA and transposable elements such as retro- transposons which could remodel former ...
Magnetic properties of the spin S = 1/2 Heisenberg chain with hexamer modulation of exchange.
Naseri, M Shahri; Japaridze, G I; Mahdavifar, S; Shayesteh, S Farjami
2012-03-21
We consider the spin-1/2 Heisenberg chain with alternating spin exchange in the presence of additional modulation of exchange on odd bonds with period 3. We study the ground state magnetic phase diagram of this hexamer spin chain in the limit of very strong antiferromagnetic (AF) exchange on odd bonds using the numerical Lanczos method and bosonization approach. In the limit of strong magnetic field commensurate with the dominating AF exchange, the model is mapped onto an effective XXZ Heisenberg chain in the presence of uniform and spatially modulated fields, which is studied using the standard continuum-limit bosonization approach. In the absence of additional hexamer modulation, the model undergoes a quantum phase transition from a gapped phase into the only one gapless Lüttinger liquid (LL) phase by increasing the magnetic field. In the presence of hexamer modulation, two new gapped phases are identified in the ground state at magnetization equal to [Formula: see text] and [Formula: see text] of the saturation value. These phases reveal themselves also in the magnetization curve as plateaus at corresponding values of magnetization. As a result, the magnetic phase diagram of the hexamer chain shows seven different quantum phases, four gapped and three gapless, and the system is characterized by six critical fields which mark quantum phase transitions between the ordered gapped and the LL gapless phases. © 2012 IOP Publishing Ltd
Thermal entanglement of a spin-1/2 Ising-Heisenberg model on a symmetrical diamond chain.
Ananikian, N S; Ananikyan, L N; Chakhmakhchyan, L A; Rojas, Onofre
2012-06-27
The entanglement quantum properties of a spin-1/2 Ising-Heisenberg model on a symmetrical diamond chain were analyzed. Due to the separable nature of the Ising-type exchange interactions between neighboring Heisenberg dimers, calculation of the entanglement can be performed exactly for each individual dimer. Pairwise thermal entanglement was studied in terms of the isotropic Ising-Heisenberg model and analytical expressions for the concurrence (as a measure of bipartite entanglement) were obtained. The effects of external magnetic field H and next-nearest neighbor interaction J(m) between nodal Ising sites were considered. The ground state structure and entanglement properties of the system were studied in a wide range of coupling constant values. Various regimes with different values of ground state entanglement were revealed, depending on the relation between competing interaction strengths. Finally, some novel effects, such as the two-peak behavior of concurrence versus temperature and coexistence of phases with different values of magnetic entanglement, were observed.
FGFR2 mutation in 46,XY sex reversal with craniosynostosis.
Bagheri-Fam, Stefan; Ono, Makoto; Li, Li; Zhao, Liang; Ryan, Janelle; Lai, Raymond; Katsura, Yukako; Rossello, Fernando J; Koopman, Peter; Scherer, Gerd; Bartsch, Oliver; Eswarakumar, Jacob V P; Harley, Vincent R
2015-12-01
Patients with 46,XY gonadal dysgenesis (GD) exhibit genital anomalies, which range from hypospadias to complete male-to-female sex reversal. However, a molecular diagnosis is made in only 30% of cases. Heterozygous mutations in the human FGFR2 gene cause various craniosynostosis syndromes including Crouzon and Pfeiffer, but testicular defects were not reported. Here, we describe a patient whose features we would suggest represent a new FGFR2-related syndrome, craniosynostosis with XY male-to-female sex reversal or CSR. The craniosynostosis patient was chromosomally XY, but presented as a phenotypic female due to complete GD. DNA sequencing identified the FGFR2c heterozygous missense mutation, c.1025G>C (p.Cys342Ser). Substitution of Cys342 by Ser or other amino acids (Arg/Phe/Try/Tyr) has been previously reported in Crouzon and Pfeiffer syndrome. We show that the 'knock-in' Crouzon mouse model Fgfr2c(C342Y/C342Y) carrying a Cys342Tyr substitution displays XY gonadal sex reversal with variable expressivity. We also show that despite FGFR2c-Cys342Tyr being widely considered a gain-of-function mutation, Cys342Tyr substitution in the gonad leads to loss of function, as demonstrated by sex reversal in Fgfr2c(C342Y/-) mice carrying the knock-in allele on a null background. The rarity of our patient suggests the influence of modifier genes which exacerbated the testicular phenotype. Indeed, patient whole exome analysis revealed several potential modifiers expressed in Sertoli cells at the time of testis determination in mice. In summary, this study identifies the first FGFR2 mutation in a 46,XY GD patient. We conclude that, in certain rare genetic contexts, maintaining normal levels of FGFR2 signaling is important for human testis determination. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
de Silva, K S H; Sirisena, N D; Wijenayaka, H K; Cooray, J G; Jayasekara, R W; Dissanayake, V H W
2015-12-01
There are several conditions giving rise to 46, XY disorders of sex development (DSD) with different modes of inheritance. Therefore definitive diagnosis based on molecular genetic confirmation would be the ideal to counsel parents regarding the future implications of the condition affecting their baby. This is the first report from Sri Lanka documenting the presence of mutations in the androgen receptor (AR) gene in a cohort of children with 46, XY DSD. To describe the socio-demographic and clinical features and document the presence of mutations in the androgen receptor (AR) gene in a cohort of children with 46, XY DSD. 46, XY patients with ambiguous genitalia followed up in the University Unit at the Lady Ridgeway Hospital, Colombo, and clinically identified as having androgen insensitivity syndrome (AIS) or a testosterone biosynthetic defect were recruited for the study. Their socio-demographic details and clinical features were documented. Exons 1 to 8 of the AR gene were screened for mutations by DNA sequencing on a venous blood sample. SRY gene mutations were also assayed. Thirty-four patients were studied, 3 of whom were clinically diagnosed as having complete androgen insensitivity syndrome (CAIS). Sex of rearing was female and male in 4 and 30 respectively. AR gene mutations were detected in 6 patients (17.6%). None of the patients had SRY gene mutations. Majority (88%) of the patients were raised as males. Six patients (17.6%) including the 3 with CAIS, had genetically confirmed AIS with the detection of AR gene mutations.
Energy Technology Data Exchange (ETDEWEB)
Brymora, Katarzyna; Calvayrac, Florent, E-mail: Florent.Calvayrac@univ-lemans.fr
2017-07-15
Highlights: • A new method is given to extract surface anisotropies from ab initio calculations. • Heisenberg model for magnetic clusters and surfaces is validated in simple cases. • Ligands, metallic clusters, or coatings degrade the validity of the Heisenberg model. • Values for surface anisotropies, volume anisotropies, exchange constants are computed. • Results are in agreement with experimental data, previous theoretical findings. - Abstract: We performed ab initio computations of the magnetic properties of simple iron oxide clusters and slabs. We considered an iron oxide cluster functionalized by a molecule or glued to a gold cluster of the same size. We also considered a magnetite slab coated by cobalt oxide or a mixture of iron oxide and cobalt oxide. The changes in magnetic behavior were explored using constrained magnetic calculations. A possible value for the surface anisotropy was estimated from the fit of a classical Heisenberg model on ab initio results. The value was found to be compatible with estimations obtained by other means, or inferred from experimental results. The addition of a ligand, coating, or of a metallic nanoparticle to the systems degraded the quality of the description by the Heisenberg Hamiltonian. Proposing a change in the anisotropies allowing for the proportion of each transition atom we could get a much better description of the magnetism of series of hybrid cobalt and iron oxide systems.
Fu, X H; Zhang, W Q; Qu, X S
2016-03-31
We performed an exploratory study by analyzing the correlation of 46, XY disorders of sex development (46, XY DSD) with androgen receptor (AR) and steroid 5α-reductase-2 (SRD5A2) gene mutations and a safety analysis of dihydrotestosterone (DHT) gel treatment for pediatric micropenis. We collected samples from 76 pediatric patients with 46, XY DSD and 50 healthy adult men with normal fertility as the control group. The pediatric patients were treated with DHT gel (0.1-0.3 mg/kg/day) for three to six months. The extended penis length, testicular volume, and multiple blood parameters were collected before treatment and one, three, and six months after treatment. Of the 76 cases with 46, XY DSD, 31.58% had hypospadias with micropenis and 6.58% had male pseudohermaphroditism. Through AR gene screening, it was found that 14 patients had AR point mutations and 22 patients had SRD5A2 mutations. After treatment with DHT, the penis length of the patients significantly improved after one, three, and six months of treatment, with longer treatment times resulting in greater improvement. Before treatment with DHT, the average serum DHT value of patients with 46, XY DSD was 24.29 pg/mL. After one, three, and six months of treatment, this value increased to 430.71, 328.9, and 323.6 pg/mL, respectively. We conclude that for pediatric patients who have male hermaphroditism or hypospadias with micropenis, AR and SRD5A2 gene mutation detection should be performed. Local application of DHT gel can promote penis growth effectively without systemic adverse reactions.
A microcomputer-controlled X-Y translator for CNC laser applications
Crane, K. C. A.; Hosea, T. J. C.; Lam, C. H.; Bendeli, A.
1984-04-01
An inexpensive X-Y translator is described that is designed for industrial and laboratory laser applications such as cutting and heat treatment requiring computer numerical control. The system includes standard stepper motors, lead screws and carriages, but is unusual in that although versatile it requires only an inexpensive Apple ll microcomputer for control and for creation of data files. The selected translation speed is maintained constant regardless of direction. Speeds up to about 3000 steps s -1 are obtained. A single file of pattern information contains up to 400 segments, which may be straight lines or circular arcs.
Quantum Chernoff bound metric for the XY model at finite temperature
Abasto, Damian F.; Jacobson, N. Tobias; Zanardi, Paolo
2008-02-01
We explore the finite-temperature phase diagram of the anisotropic XY spin chain using the quantum Chernoff bound metric on thermal states. The analysis of the metric elements allows one to easily identify, in terms of different scaling with temperature, quasiclassical and quantum-critical regions. These results extend recent ones obtained using the Bures metric and show that different information-theoretic notions of distance can carry the same sophisticated information about the phase diagram of an interacting many-body system featuring quantum-critical points.
Energy Technology Data Exchange (ETDEWEB)
Neto, Minos A., E-mail: minos@pq.cnpq.br [Departamento de Fisica, Universidade Federal do Amazonas, 3000, Japiim, Manaus, 69077-000 AM (Brazil); Roberto Viana, J., E-mail: vianafisica@bol.com.br [Departamento de Fisica, Universidade Federal do Amazonas, 3000, Japiim, Manaus, 69077-000 AM (Brazil); Ricardo de Sousa, J., E-mail: jsousa@edu.ufam.br [Departamento de Fisica, Universidade Federal do Amazonas, 3000, Japiim, Manaus, 69077-000 AM (Brazil); National Institute of Science and Technology for Complex Systems, 3000, Japiim, Manaus, 69077-000 AM (Brazil)
2012-08-15
In this work we study the critical behavior of the quantum spin-1/2 anisotropic Heisenberg antiferromagnet in the presence of a longitudinal field on a body centered cubic (bcc) lattice as a function of temperature, anisotropy parameter ({Delta}) and magnetic field (H), where {Delta}=0 and 1 correspond the isotropic Heisenberg and Ising models, respectively. We use the framework of the differential operator technique in the effective-field theory with finite cluster of N=4 spins (EFT-4). The staggered m{sub s}=(m{sub A}-m{sub B})/2 and total m=(m{sub A}+m{sub B})/2 magnetizations are numerically calculated, where in the limit of m{sub s}{yields}0 the critical line T{sub N}(H,{Delta}) is obtained. The phase diagram in the T-H plane is discussed as a function of the parameter {Delta} for all values of H Element-Of [0,H{sub c}({Delta})], where H{sub c}({Delta}) correspond the critical field (T{sub N}=0). Special focus is given in the low temperature region, where a reentrant behavior is observed around of H=H{sub c}({Delta}){>=}H{sub c}({Delta}=1)=8J in the Ising limit, results in accordance with Monte Carlo simulation, and also was observed for all values of {Delta} Element-Of [0,1]. This reentrant behavior increases with increase of the anisotropy parameter {Delta}. In the limit of low field, our results for the Heisenberg limit are compared with series expansion values. - Highlights: Black-Right-Pointing-Pointer In the lat decade there has been a great interest in the physics of the quantum phase transition in spins system. Black-Right-Pointing-Pointer Effective-field theory in cluster with N=4 spins is generalized to treat the quantum spin-1/2 Heisenberg model. Black-Right-Pointing-Pointer We have obtained phase diagram at finite temperature for the quantum spin-1/2 antiferromagnet Heisenberg model as a bcc lattice.
Adiabatically modeling quantum gates with two-site Heisenberg spins chain: Noise vs interferometry
Jipdi, M. N.; Tchoffo, M.; Fai, L. C.
2018-02-01
We study the Landau Zener (LZ) dynamics of a two-site Heisenberg spin chain assisted with noise and focus on the implementation of logic gates via the resulting quantum interference. We present the evidence of the quantum interference phenomenon in triplet spin states and confirm that, three-level systems mimic Landau-Zener-Stückelberg (LZS) interferometers with occupancies dependent on the effective phase. It emerges that, the critical parameters tailoring the system are obtained for constructive interferences where the two sets of the chain are found to be maximally entangled. Our findings demonstrate that the enhancement of the magnetic field strength suppresses noise effects; consequently, the noise severely impacts the occurrence of quantum interference for weak magnetic fields while for strong fields, quantum interference subsists and allows the modeling of universal sets of quantum gates.
Fractional vortices in the XY model with {pi} bonds
Energy Technology Data Exchange (ETDEWEB)
Kulkarni, R. V.; Almaas, E.; Fisher, K. D.; Stroud, D.
2000-11-01
We define a new set of excitations in the XY model which we call ''fractional vortices.'' In the frustrated XY model containing {pi} bonds, we make the ansatz that the ground state configurations can be characterized by pairs of oppositely charged fractional vortices. For a chain of {pi} bonds, the ground state energy and the phase configurations calculated on the basis of this ansatz agree well with the results from direct numerical simulations. Finally, we discuss the possible connection of these results to some recent experiments by Kirtley [Phys. Rev. B 51, R12057 (1995)] on high-T{sub c} superconductors where fractional flux trapping was observed along certain grain boundaries.
XY-model on planar and space curves
Energy Technology Data Exchange (ETDEWEB)
Dandoloff, Rossen [Laboratoire de Physique et Modelisation, Universite de Cergy-Pontoise, F-95302 Cergy-Pontoise (France); Saxena, Avadh [Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)]. E-mail: avadh@lanl.gov
2006-10-30
We study the XY-model on a planar curve with a segment with constant curvature {kappa}{sub 0} and a space curve with a segment with both constant curvature {kappa}{sub 0} and torsion {tau}{sub 0}. In the first case the bent segment breaks the rotational invariance of the XY-model and thus we get a fractional static sine-Gordon soliton interpolating between the two states {theta}{sub 1} and {theta}{sub 2}. In the second case the helical segment breaks the helicity of the model and thus creating a ground state and a metastable state spin configuration with a fractional static soliton. For sufficiently large {tau}{sub 0} the static soliton solution can be more stable than the trivial ({theta}=n{pi}/2) solution. The curvature introduces nonlinearity in the problem thereby localizing the energy in the region with nonzero curvature.
Review and management of 46,XY disorders of sex development.
Massanyi, Eric Z; Dicarlo, Heather N; Migeon, Claude J; Gearhart, John P
2013-06-01
Disorders of sex development (DSD) among 46,XY individuals are rare and challenging conditions. Abnormalities of karyotype, gonadal formation, androgen synthesis, and androgen action are responsible for the multiple disorders that result in undervirilization during development. Phenotypic appearance and timing of presentation are quite variable. The focus of treatment has shifted from early gender assignment and corrective surgery to careful diagnosis, proper education of patients and their families, and individualized treatment by a multi-disciplinary team. The modern management of these patients is difficult and controversial. Conflicting data on long-term outcomes of these individuals have been reported in the literature. The various etiologies of 46,XY DSD, current approaches to diagnosis and treatment, and reported long-term results are reviewed. Copyright © 2012 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.
Spin and energy correlations in the one dimensional spin 1/2 Heisenberg model
Naef, F.; Zotos, X.
1997-01-01
In this paper, we study the spin and energy dynamic correlations of the one dimensional spin 1/2 Heisenberg model, using mostly exact diagonalization numerical techniques. In particular, observing that the uniform spin and energy currents decay to finite values at long times, we argue for the absence of spin and energy diffusion in the easy plane anisotropic Heisenberg model.
Directory of Open Access Journals (Sweden)
Mao-Hsiung Chiang
2010-03-01
Full Text Available This study aims to develop a X-Y dual-axial intelligent servo pneumatic-piezoelectric hybrid actuator for position control with high response, large stroke (250 mm, 200 mm and nanometer accuracy (20 nm. In each axis, the rodless pneumatic actuator serves to position in coarse stroke and the piezoelectric actuator compensates in fine stroke. Thus, the overall control systems of the single axis become a dual-input single-output (DISO system. Although the rodless pneumatic actuator has relatively larger friction force, it has the advantage of mechanism for multi-axial development. Thus, the X-Y dual-axial positioning system is developed based on the servo pneumatic-piezoelectric hybrid actuator. In addition, the decoupling self-organizing fuzzy sliding mode control is developed as the intelligent control strategies. Finally, the proposed novel intelligent X-Y dual-axial servo pneumatic-piezoelectric hybrid actuators are implemented and verified experimentally.
Fidelity Approach to the Disordered Quantum XY Model
Garnerone, Silvano; Jacobson, N. Tobias; Haas, Stephan; Zanardi, Paolo
2009-02-01
We study the random XY spin chain in a transverse field by analyzing the susceptibility of the ground state fidelity, numerically evaluated through a standard mapping of the model onto quasifree fermions. It is found that the fidelity susceptibility and its scaling properties provide useful information about the phase diagram. In particular it is possible to determine the Ising critical line and the Griffiths phase regions, in agreement with previous analytical and numerical results.
Factorization and Criticality in the Anisotropic XY Chain via Correlations
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Barış Çakmak
2015-02-01
Full Text Available In this review, we discuss the zero and finite temperature behavior of various bipartite quantum and total correlation measures, the skew information-based quantum coherence and the local quantum uncertainty in the thermal ground state of the one-dimensional anisotropic XY model in a transverse magnetic field. We compare the ability of the considered measures to correctly detect or estimate the quantum critical point and the non-trivial factorization point possessed by the spin chain.
Frustration-Induced Ferrimagnetism in Heisenberg Spin Chains
Shimokawa, Tokuro; Nakano, Hiroki
2011-01-01
We study ground-state properties of the Heisenberg frustrated spin chain with interactions up to fourth nearest neighbors by the exact-diagonalization method and the density matrix renormalization group method. We find that ferrimagnetism is realized not only in the case of S=1/2 but also S=1 despite that there is only a single spin site in each unit cell determined from the shape of the Hamiltonian. Our numerical results suggest that a "multi-sublattice structure" is not required for the occ...
Quantum Correlations and Teleportation in Heisenberg XX Spin Chain
Qin, Wan; Guo, Jin-Liang
2015-07-01
We investigate the thermal quantum correlations in the Heisenberg XX spin chain, and the teleportation of a two-qubit entangled state via the spin chain is analyzed. It is found that the effects of external magnetic field and three-site interaction on the thermal entanglement and quantum discord between the nearest or the next nearest neighbor qubits behave differently in various aspects. Special attention is paid to how to enhance the quantum correlations of the output state and the average fidelity of the teleportation. We find that quantum discord gives a better performance in the quantum correlations transmission, and the three-site interaction is necessary for a successful teleportation.
Heisenberg exchange enhancement by orbital relaxation in cuprate compounds
van Oosten, A.B.; Broer, R.; Nieuwpoort, WC
1996-01-01
We calculate the Heisenberg exchange J in the quasi-2D antiferromagnetic cuprates La2CuO4, YBa2Cu3O6, Nd2CuO4 and Sr2CuO2Cl2. We apply all-electron (MC)SCF and non-orthogonal CI calculations to [Cu2O11](18-), [Cu2O9](14-), [Cu2O7](10-) and [Cu2O7Cl4](14-) clusters in a model charge embedding. The
A Liouville Theorem for Nonlocal Equations in the Heisenberg Group
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Eleonora Cinti
2014-12-01
Full Text Available We establish a Liouville-type theorem for a subcritical nonlinear problem, involving a fractional power of the sub-Laplacian in the Heisenberg group. To prove our result we will use the local realization of fractional CR covariant operators, which can be constructed as the Dirichlet-to-Neumann operator of a degenerate elliptic equation in the spirit of Caffarelli and Silvestre [8], as established in [14]. The main tools in our proof are the CR inversion and the moving plane method, applied to the solution of the lifted problem in the half-space ℍn × ℝ+.
Q-operators for the open Heisenberg spin chain
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Rouven Frassek
2015-12-01
Full Text Available We construct Q-operators for the open spin-12 XXX Heisenberg spin chain with diagonal boundary matrices. The Q-operators are defined as traces over an infinite-dimensional auxiliary space involving novel types of reflection operators derived from the boundary Yang–Baxter equation. We argue that the Q-operators defined in this way are polynomials in the spectral parameter and show that they commute with transfer matrix. Finally, we prove that the Q-operators satisfy Baxter's TQ-equation and derive the explicit form of their eigenvalues in terms of the Bethe roots.
Thermal quantum discord in the Heisenberg chain with impurity
Energy Technology Data Exchange (ETDEWEB)
Gong, Jia-Min, E-mail: jmgong@yeah.net; Hui, Zhan-Qiang
2014-07-01
We study thermal quantum discord (TQD) in the Heisenberg chain with spin site or magnetic impurity. The former one of which may induce inhomogeneous exchange interactions between the neighboring spins, while the latter one may model a spin chain with nonuniform magnetic field. In contrast to one's traditional understanding, we found that the spin impurity can be used to enhance the TQD greatly for all the bipartition schemes of the chain, while the magnetic impurity located on one spin can make the TQD between the other two spins approaching its maximum 1 for the antiferromagnetic chain.
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Christoph P. Hofmann
2016-03-01
Full Text Available The low-temperature properties of systems characterized by a spontaneously broken internal rotation symmetry, O(N→O(N−1, are governed by Goldstone bosons and can be derived systematically within effective Lagrangian field theory. In the present study we consider systems living in two spatial dimensions, and evaluate their partition function at low temperatures and weak external fields up to three-loop order. Although our results are valid for any such system, here we use magnetic terminology, i.e., we refer to quantum spin systems. We discuss the sign of the (pseudo-Goldstone boson interaction in the pressure, staggered magnetization, and susceptibility as a function of an external staggered field for general N. As it turns out, the d=2+1 quantum XY model (N=2 and the d=2+1 Heisenberg antiferromagnet (N=3, are rather special, as they represent the only cases where the spin-wave interaction in the pressure is repulsive in the whole parameter regime where the effective expansion applies. Remarkably, the d=2+1 XY model is the only system where the interaction contribution in the staggered magnetization (susceptibility tends to positive (negative values at low temperatures and weak external field.
2d Affine XY-Spin Model/4d Gauge Theory Duality and Deconfinement
Energy Technology Data Exchange (ETDEWEB)
Anber, Mohamed M.; Poppitz, Erich; /Toronto U.; Unsal, Mithat; /SLAC /Stanford U., Phys. Dept. /San Francisco State U.
2012-08-16
We introduce a duality between two-dimensional XY-spin models with symmetry-breaking perturbations and certain four-dimensional SU(2) and SU(2) = Z{sub 2} gauge theories, compactified on a small spatial circle R{sup 1,2} x S{sup 1}, and considered at temperatures near the deconfinement transition. In a Euclidean set up, the theory is defined on R{sup 2} x T{sup 2}. Similarly, thermal gauge theories of higher rank are dual to new families of 'affine' XY-spin models with perturbations. For rank two, these are related to models used to describe the melting of a 2d crystal with a triangular lattice. The connection is made through a multi-component electric-magnetic Coulomb gas representation for both systems. Perturbations in the spin system map to topological defects in the gauge theory, such as monopole-instantons or magnetic bions, and the vortices in the spin system map to the electrically charged W-bosons in field theory (or vice versa, depending on the duality frame). The duality permits one to use the two-dimensional technology of spin systems to study the thermal deconfinement and discrete chiral transitions in four-dimensional SU(N{sub c}) gauge theories with n{sub f} {ge} 1 adjoint Weyl fermions.
Understanding the genetic aetiology in patients with XY DSD.
Ahmed, S F; Bashamboo, A; Lucas-Herald, A; McElreavey, K
2013-01-01
Disorders of sex development (DSD) consist of a wide range of disorders and are commoner in those with an XY karyotype. In over half of these cases who have a 46,XY karyotype and who are raised as boys, the underlying aetiology remains unclear. Identification of the underlying genetic abnormality may predict long-term outcome. However, genetic abnormalities that are associated with XY DSD manifest themselves with a wide range of phenotype. To understand the aetiology as well as the phenotypic variation, there is a need to harness the advanced genetic technology that is now available. The point at which genetic analysis should be undertaken in the course of investigations is unclear. In addition, there is little agreement on the most effective approach for genetic analysis that will be of clinical benefit to the patient. There is a need to understand and improve the clinical utility of genetic analysis in the clinical setting of the patient with a suspected DSD. This will be even more important when parallel gene sequencing identifies variations in multiple genes.
SIJMONS, RH; LEEGTE, B; VANLINGEN, RA; DEPATER, JM; VANDERVEEN, AY; DELCANHO, H; TENKATE, LP; BREED, ASPM
1993-01-01
We describe a 1-year-old boy with a rare de novo 46,XY/47,XY,+ i(5p) mosaicism (ratios 28/3 in peripheral blood lymphocytes and 2/12 in skin fibroblasts). The boy, born after a pregnancy of 34 weeks, had lung hypoplasia, persistent hypotonia, and postnatal growth failure. Craniofacial anomalies were
Numerical analysis of magnetic states mixing in the Heisenberg model with the dihedral symmetry
Directory of Open Access Journals (Sweden)
Jaśniewicz-Pacer K.
2013-01-01
Full Text Available The total spin number S is not a ‘good quantum number for’ the Heisenberg model with singleion anisotropy, so the Hamiltonian eigenstates with diﬀerent S may form linear combinations. Sometimes it is assumed that S can be used as an ‘approximate quantum number’, though some results show that mixing of S-states is important in investigations of magnetic molecules. Some small spin systems with the dihedral symmetry are analyzed to investigate diﬀerent schemes of mixing and its dependence on the anisotropy parameter. The results show various behavior of the magnetic state mixing. The mean (over a state value of total spin is quite stable for the ground state, but in other cases this dependence is nonlinear and sometimes non-monotonic.
Various Correlations in the Anisotropic Heisenberg XYZ Model with Dzyaloshinski—Moriya Interaction
Tursun, Mamtimin; Abliz, Ahmad; Mamtimin, Rabigul; Abliz, Ablimit; Qiao, Pan-Pan
2013-03-01
Various thermal correlations as well as the effect of intrinsic decoherence on the correlations are studied in a two-qubit Heisenberg XYZ spin chain with the Dzyaloshinski—Moriya (DM) interaction along the z direction, i.e. Dz. It is found that tunable parameter Dz may play a constructive role on the concurrence C, classical correlation (CC) and quantum discord (QD) in thermal equilibrium while it plays a destructive role on the correlations in the intrinsic decoherence case. The entanglement and quantum discord exhibit collapse and revival under the phase decoherence. With a proper combination of the system parameters, the correlations can effectively be kept at high steady state values despite the intrinsic decoherence.
Nishimoto, Satoshi; Shibata, Naokazu; Hotta, Chisa
2013-01-01
Quantum spin-1/2 kagome Heisenberg antiferromagnet is the representative frustrated system possibly hosting a spin liquid. Clarifying the nature of this elusive topological phase is a key challenge in condensed matter; however, even identifying it still remains unsettled. Here we apply a magnetic field and discover a series of spin-gapped phases appearing at five different fractions of magnetization by means of a grand canonical density matrix renormalization group, an unbiased state-of-the-art numerical technique. The magnetic field dopes magnons and first gives rise to a possible Z₃ spin liquid plateau at 1/9 magnetization. Higher field induces a self-organized super-lattice unit, a six-membered ring of quantum spins, resembling an atomic orbital structure. Putting magnons into this unit one by one yields three quantum solid plateaus. We thus find that the magnetic field could control the transition between various emergent phases by continuously releasing the frustration.
Entanglement-free Heisenberg-limited phase estimation.
Higgins, B L; Berry, D W; Bartlett, S D; Wiseman, H M; Pryde, G J
2007-11-15
Measurement underpins all quantitative science. A key example is the measurement of optical phase, used in length metrology and many other applications. Advances in precision measurement have consistently led to important scientific discoveries. At the fundamental level, measurement precision is limited by the number N of quantum resources (such as photons) that are used. Standard measurement schemes, using each resource independently, lead to a phase uncertainty that scales as 1/square root N-known as the standard quantum limit. However, it has long been conjectured that it should be possible to achieve a precision limited only by the Heisenberg uncertainty principle, dramatically improving the scaling to 1/N (ref. 3). It is commonly thought that achieving this improvement requires the use of exotic quantum entangled states, such as the NOON state. These states are extremely difficult to generate. Measurement schemes with counted photons or ions have been performed with N theory to achieve a standard deviation scaling at the Heisenberg limit. For the largest number of resources used (N = 378), we estimate an unknown phase with a variance more than 10 dB below the standard quantum limit; achieving this variance would require more than 4,000 resources using standard interferometry. Our results represent a drastic reduction in the complexity of achieving quantum-enhanced measurement precision.
An autosomal locus controls sex reversal in interspecific XY hybrids of the medaka fishes.
Kato, M; Takehana, Y; Fukuda, Y; Naruse, K; Sakaizumi, M; Hamaguchi, S
2011-12-01
Although the two medaka species Oryzias latipes and O. curvinotus share the sex-determining gene Dmy, XY sex reversal occurs in interspecific hybridization between O. latipes females of the Hd-rR inbred strain and O. curvinotus males. In this Hd-rR-curvinotus mating, all XX and XY hybrids developed as females. In this study, we used another O. latipes inbred strain (HNI) for the mating, and found that 23% of XY hybrids developed as males, although all XX and the remaining XY hybrids developed as females. Linkage analysis using 236 XY hybrid males obtained from (Hd-rR × HNI) F(1) females showed that a single major locus, Hybrid maleless (Hml), on autosomal linkage group 17, contributed to the strain difference in the XY sex reversal. Furthermore, we found that crossing females of a different O. latipes inbred strain, HO4C, did not cause XY sex reversal in the interspecific hybrids, and that the XY hybrids from (Hd-rR × HO4C) F(1) females showed a 1:1 sex ratio. XY hybrid males had the HO4C allele at sequence-tagged site loci around the Hml locus whereas XY females had the Hd-rR allele, confirming the strong contribution of this locus to XY sex reversal. Reverse transcriptase PCR analysis showed a reduced expression of Dmy(curvinotus) in XY fry of the Hd-rR-curvinotus hybrids at hatching. These results suggest that the Hd-rR allele at the Hml locus interfere with the function of Dmy(curvinotus) on a hybrid background, thus resulting in XY sex reversal.
DEFF Research Database (Denmark)
Berglund, Agnethe; Johannsen, Trine H; Krag, Kirstine Stochholm
2016-01-01
CONTEXT: The prevalence of phenotypic females with a 46,XY karyotype is low, thus current knowledge about age and clinical presentation at diagnosis is sparse even for the most frequent conditions, androgen insensitivity syndrome (AIS), and gonadal dysgenesis. OBJECTIVE: To estimate incidence......, prevalence, age at diagnosis, and clinical presentation at diagnosis in 46,XY females. DESIGN AND SETTING: A nationwide study covering all known females with a 46,XY karyotype in Denmark since 1960. The diagnosis of 46,XY disorder of sex development (DSD) was determined by medical record evaluation, data...... from the Danish National Patient Registry, and genetic testing, if available. PATIENTS: A total of 166 females registered as 46,XY females in the Danish Cytogenetic Central Registry were identified. RESULTS: A total of 124 females were classified as having 46,XY DSD, 78 with AIS and 25 with gonadal...
Su, Yao Heng; Chen, Ai Min; Wang, Honglei; Xiang, Chunhuan
2017-10-01
We investigated the quantum phase transition occurred in one-dimensional quantum Heisenberg XYZ model with Dzyaloshinskii-Moriya interaction via the infinite matrix product state representation with the infinite time evolving block decimation method. Entanglement entropy and local order parameter in and near the transition point are given. Scaling relation plays crucial roles on identifying a quantum system with a physically different phase. The scaling relation of the entanglement entropy, local order parameter and finite correlation length with the truncation dimension are also obtained. All the interesting results give a theoretical justification for the high accuracy of infinite time evolved block decimation algorithm which works in the thermodynamical limit.
Kouri, Donald J; Markovich, Thomas; Maxwell, Nicholas; Bodmann, Bernhard G
2009-07-02
We discuss a periodic variant of the Heisenberg-Weyl algebra, associated with the group of translations and modulations on the circle. Our study of uncertainty minimizers leads to a periodic version of canonical coherent states. Unlike the canonical, Cartesian case, there are states for which the uncertainty product associated with the generators of the algebra vanishes. Next, we explore the supersymmetric (SUSY) quantum mechanical setting for the uncertainty-minimizing states and interpret them as leading to a family of "hindered rotors". Finally, we present a standard quantum mechanical treatment of one of these hindered rotor systems, including numerically generated eigenstates and energies.
Design and Analysis of a New High Precision Decoupled XY Compact Parallel Micromanipulator
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Xigang Chen
2017-03-01
Full Text Available With the development of nanotechnology that contains automatic control, precision machinery and precise measurement, etc., micro/nano manipulation has become a new research direction in recent years. This paper presents the design and analysis procedures of a new high precision XY decoupled compact parallel micromanipulator (DCPM for micro scale positioning applications. The DCPM is made up of the decoupler, two-stage amplifier and the piezoelectric translator (PZT actuators, which utilizes the characteristics of flexure hinges. In this paper, firstly, a new two-stage bridge-principle amplifier is proposed by a serial connection of two fundamental bridge amplifiers in order to increase the ratio of amplification. It is pivotal for designing the micromanipulator. Then, the kinematic modeling of the micromanipulator is carried out by resorting to stiffness and compliance analysis via matrix method. Finally, the performance of the micromanipulator is validated by finite-element analysis (FEA which is preliminary job for fabricating the prototype and designing the control system of the XY stage that is expected to be adopted into micro/nano manipulations.
A rare case report of 46XY mixed gonadal dysgenesis
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Rakesh Arora
2013-01-01
Full Text Available A 16-year-old person, reared as female presented with complaints of genital ambiguity and primary amenorrhoea along with lack of secondary sexual characters, but without short stature and Turner′s stigmata. She was taking steroids after being misdiagnosed as congenital adrenal hyperplasia (CAH. Karyotype analysis revealed 46XY karyotype. There was no evidence of hypocortisolemia (cortisol 9.08 μg/dl, adrenocorticotropic hormone [ACTH] 82.5 pg/ml or elevated level of 17-OH-progesterone (0.16 ng/ml. Pooled luteinizing hormone (LH was 11.79 mIU/ml and follicle-stimulating hormone (FSH was 66.37 mIU/ml. Serum estradiol level was 25 pg/ml (21-251. Basal and 72 h post beta-human chorionic gonadotropin (hCG levels of androstenedione and testosterone levels were done (basal testosterone of 652 ng/dl and basal androstenedione of 1.17 ng/ml; 72 h post hCG testosterone of 896 ng/dl and androstenedione of 1.34 ng/ml. Magnetic resonance imaging (MRI pelvis (with ultrasonogrphy [USG] correlation revealed uterus didelphys with obstructed right moiety and bilateral ovarian-like structures. Right sided gonads and adjacent tubal structures were visualized laparoscopically and removed. Left sided gonads were not visualized and Mullerian remnants were adhered to sigmoid colon. Histopathological examination revealed presence of testicular tissue showing atrophic seminiferous tubules with hyperplasia of Leydig cells. No ovarian tissue was seen. Based on these results a diagnosis of 46XY mixed gonadal dysgenesis (MGD was made, which is rare and is difficult to distinguish from 46XY ovotesticular disorder of sexual differentiation (OT-DSD. The patient was managed with a multidisciplinary approach and fertility issues discussed with the patient′s caregivers.
Acne in Klinefelter syndrome-46XY/47XXY mosaicism?
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Chembolli Lakshmi
2015-01-01
Full Text Available Klinefelter syndrome (KFS is the most common non-heritable sex chromosome anomaly caused by nondisjunction during cell division and contains two or more X chromosomes. More than two third of all cases are homogenous (47XXY and the remaining are mosaic (46XY/47XXY. Lower limb ulcers are frequently observed and attributed to impaired fibrinolysis. A case of KFS with post acne scars and leg ulcers is presented. The rarity of acne in this syndrome is explained by the phenomenon of mosaicism.
Non-Equilibrium Steady States of the XY Chain
Aschbacher, W H
2002-01-01
We study the non-equilibrium statistical mechanics of the two-sided XY chain. We start from an initial state in which the left and right part of the lattice {x|xM}, are at inverse temperatures beta_L and beta_R. Using a simple scattering theoretic analysis, we construct the unique non-equilibrium steady state (NESS). This state depends on beta_L and beta_R, but not on the choice of the decoupling parameter M. We prove that in the non-equilibrium case, beta_L \
Pure XY gonadal dysgenesis and agenesis in monozygotic twins.
Chen, Hui-Yu; Huang, Hong-Yuan; Chang, Ting-Chang; Lai, Chyong-Huey; Soong, Yung-Kuei
2006-04-01
To report a case of monozygotic twin sisters who had discordant gonadal dysgenesis although each had a normal 46,XY karyotype. Case report. University tertiary hospital. Seventeen-year-old twin sisters, one with gonadal agenesis and the other with pure gonadal dysgenesis followed by dysgerminoma. Blood samples were obtained for karyotyping and short tandem repeat polymorphism analysis (10 markers). Both patients underwent gonadectomy. Both sisters are well at time of report after gonadectomy for the sister with dysgerminoma and diagnostic laparoscope for the other. Dysgerminoma and atrophic ovarian stromal and tubal structures. Monozygotic twins can have discordant gonadal dysgenesis even though they are identical genetically.
Khatami, Ehsan; Singh, Rajiv R. P.; Rigol, Marcos
2011-12-01
We study the Heisenberg model on the pinwheel distorted kagome lattice as observed in the material Rb2Cu3SnF12. Experimentally relevant thermodynamic properties at finite temperatures are computed utilizing numerical linked-cluster expansions. We also develop a Lanczos-based, zero-temperature, numerical linked-cluster expansion to study the approach of the pinwheel distorted lattice to the uniform kagome-lattice Heisenberg model. We find strong evidence for a phase transition before the uniform limit is reached, implying that the ground state of the kagome-lattice Heisenberg model is likely not pinwheel dimerized and is stable to finite pinwheel-dimerizing perturbations.
Deterministic ultracold ion source targeting the Heisenberg limit.
Schnitzler, W; Linke, N M; Fickler, R; Meijer, J; Schmidt-Kaler, F; Singer, K
2009-02-20
The major challenges to fabricate quantum processors and future nano-solid-state devices are material modification techniques with nanometer resolution and suppression of statistical fluctuations of dopants or qubit carriers. Based on a segmented ion trap with mK laser-cooled ions we have realized a deterministic single-ion source which could operate with a huge range of sympathetically cooled ion species, isotopes or ionic molecules. We have deterministically extracted a predetermined number of ions on demand and have measured a longitudinal velocity uncertainty of 6.3 m/s and a spatial beam divergence of 600 microrad. We show in numerical simulations that if the ions are cooled to the motional ground state (Heisenberg limit) nanometer spatial resolution can be achieved.
Analytical and numerical performance models of a Heisenberg Vortex Tube
Bunge, C. D.; Cavender, K. A.; Matveev, K. I.; Leachman, J. W.
2017-12-01
Analytical and numerical investigations of a Heisenberg Vortex Tube (HVT) are performed to estimate the cooling potential with cryogenic hydrogen. The Ranque-Hilsch Vortex Tube (RHVT) is a device that tangentially injects a compressed fluid stream into a cylindrical geometry to promote enthalpy streaming and temperature separation between inner and outer flows. The HVT is the result of lining the inside of a RHVT with a hydrogen catalyst. This is the first concept to utilize the endothermic heat of para-orthohydrogen conversion to aid primary cooling. A review of 1st order vortex tube models available in the literature is presented and adapted to accommodate cryogenic hydrogen properties. These first order model predictions are compared with 2-D axisymmetric Computational Fluid Dynamics (CFD) simulations.
Topology in the 2d Heisenberg Model under Gradient Flow
Sandoval, I. O.; Bietenholz, W.; de Forcrand, P.; Gerber, U.; Mejía-Díaz, H.
2017-10-01
The 2d Heisenberg model — or 2d O(3) model — is popular in condensed matter physics, and in particle physics as a toy model for QCD. Along with other analogies, it shares with 4d Yang-Mills theories, and with QCD, the property that the configurations are divided in topological sectors. In the lattice regularisation the topological charge Q can still be defined such that Q\\in {Z}. It has generally been observed, however, that the topological susceptibility {{χ }t}= /V does not scale properly in the continuum limit, i.e. that the quantity {{χ }t}{{ξ }2} diverges for ξ → ∞ (where ξ is the correlation length in lattice units). Here we address the question whether or not this divergence persists after the application of the Gradient Flow.
The elusive Heisenberg limit in quantum-enhanced metrology
Demkowicz-Dobrzański, Rafał; Kołodyński, Jan; Guţă, Mădălin
2012-01-01
Quantum precision enhancement is of fundamental importance for the development of advanced metrological optical experiments, such as gravitational wave detection and frequency calibration with atomic clocks. Precision in these experiments is strongly limited by the 1/√N shot noise factor with N being the number of probes (photons, atoms) employed in the experiment. Quantum theory provides tools to overcome the bound by using entangled probes. In an idealized scenario this gives rise to the Heisenberg scaling of precision 1/N. Here we show that when decoherence is taken into account, the maximal possible quantum enhancement in the asymptotic limit of infinite N amounts generically to a constant factor rather than quadratic improvement. We provide efficient and intuitive tools for deriving the bounds based on the geometry of quantum channels and semi-definite programming. We apply these tools to derive bounds for models of decoherence relevant for metrological applications including: depolarization, dephasing, spontaneous emission and photon loss. PMID:22990859
Heisenberg-limited atom clocks based on entangled qubits.
Kessler, E M; Kómár, P; Bishof, M; Jiang, L; Sørensen, A S; Ye, J; Lukin, M D
2014-05-16
We present a quantum-enhanced atomic clock protocol based on groups of sequentially larger Greenberger-Horne-Zeilinger (GHZ) states that achieves the best clock stability allowed by quantum theory up to a logarithmic correction. Importantly the protocol is designed to work under realistic conditions where the drift of the phase of the laser interrogating the atoms is the main source of decoherence. The simultaneous interrogation of the laser phase with a cascade of GHZ states realizes an incoherent version of the phase estimation algorithm that enables Heisenberg-limited operation while extending the coherent interrogation time beyond the laser noise limit. We compare and merge the new protocol with existing state of the art interrogation schemes, and identify the precise conditions under which entanglement provides an advantage for clock stabilization: it allows a significant gain in the stability for short averaging time.
Distillability sudden death for two-qutrit states under an XY quantum environment
Wang, Yao; Cheng, ChangCheng; Chai, BingBing; Guo, JinLiang
2018-02-01
In this study, we investigate the phenomenon of distillability sudden death (DSD) for a two-qutrit system coupled to an XY spin chain. In virtue of the negativity and realignment criterion, we show that certain initial-prepared free entangled states may become bound entangled states in a finite time. The possibility of a DSD not only depends on the initial state parameter, but is also determined by the coupling between the two-qutrit system and the spin chain. The effects of other parameters related with the system and the spin chain (e.g., the total number of spins in the spin chain, strengths of the transverse field, and anisotropy parameter) on the time-determined bound entangled state are also investigated in detail. Accordingly, some effective methods of controlling the DSD are proposed.
On the realization of artificial XY spin chains
Energy Technology Data Exchange (ETDEWEB)
Kampen, M van [Fysiska Institutionen, Box 530, 751 21 Uppsala (Sweden); Soroka, I L [Fysiska Institutionen, Box 530, 751 21 Uppsala (Sweden); Brucas, R [Fysiska Institutionen, Box 530, 751 21 Uppsala (Sweden); Hjoervarsson, B [Fysiska Institutionen, Box 530, 751 21 Uppsala (Sweden); Wieser, R [Universitaet Duisburg-Essen (Germany); Usadel, K D [Universitaet Duisburg-Essen (Germany); Hanson, M [Chalmers University of Technology, Goeteborg (Sweden); Kazakova, O [Chalmers University of Technology, Goeteborg (Sweden); Grabis, J [Ruhr-Universitaet Bochum (Germany); Zabel, H [Ruhr-Universitaet Bochum (Germany); Jozsa, C [Center for NanoMaterials and COBRA Research Institute, Eindhoven University of Technology (Netherlands); Koopmans, B [Center for NanoMaterials and COBRA Research Institute, Eindhoven University of Technology (Netherlands)
2005-01-19
Spin chains are the most elementary entities in the study of magnetic ordering behaviour. In this letter, we describe a route toward the realization of artificial XY spin chains. Using thin-film deposition and e-beam lithography, 300 and 550 nm diameter pillars consisting of alternating discs of permalloy and Al{sub 2}O{sub 3} have been made. Shape anisotropy forces the magnetization in plane, creating a chain of two-dimensional magnetic moments S{sub i}-bar. The discs couple to each other by their dipolar stray fields, resulting in an interaction of the form J{sub ij}S{sub i}-bar {center_dot}S{sub j}-bar, with J{sub ij} the coupling between discs i and j. This form closely resembles a chain of xy spins, coupled by effective interactions J{sub ij}. We present a magnetic characterization of the pillars, and compare the results with model calculations. Also, spin dynamics and ordering phenomena are addressed. (letter to the editor)
Du, Sienmi; Itoh, Noriko; Askarinam, Sahar; Hill, Haley; Arnold, Arthur P; Voskuhl, Rhonda R
2014-02-18
Women are more susceptible to multiple sclerosis (MS) and have more robust immune responses than men. However, men with MS tend to demonstrate a more progressive disease course than women, suggesting a disconnect between the severity of an immune attack and the CNS response to a given immune attack. We have previously shown in an MS model, experimental autoimmune encephalomyelitis, that autoantigen-sensitized XX lymph node cells, compared with XY, are more encephalitogenic. These studies demonstrated an effect of sex chromosomes in the induction of immune responses, but did not address a potential role of sex chromosomes in the CNS response to immune-mediated injury. Here, we examined this possibility using XX versus XY bone marrow chimeras reconstituted with a common immune system of one sex chromosomal type. We found that experimental autoimmune encephalomyelitis mice with an XY sex chromosome complement in the CNS, compared with XX, demonstrated greater clinical disease severity with more neuropathology in the spinal cord, cerebellum, and cerebral cortex. A candidate gene on the X chromosome, toll-like receptor 7, was then examined. Toll-like receptor 7 expression in cortical neurons was higher in mice with XY compared with mice with XX CNS, consistent with the known neurodegenerative role for toll-like receptor 7 in neurons. These results suggest that sex chromosome effects on neurodegeneration in the CNS run counter to effects on immune responses, and may bear relevance to the clinical enigma of greater MS susceptibility in women but faster disability progression in men. This is a demonstration of a direct effect of sex chromosome complement on neurodegeneration in a neurological disease.
There is life in the old horse yet or what else we can learn studying spin-1/2 XY chains
Derzhko, Oleg
2003-01-01
We review some recent results on statistical mechanics of the one-dimensional spin-1/2 XY systems paying special attention to the dynamic and thermodynamic properties of the models with Dzyaloshinskii-Moriya interaction, correlated disorder, and regularly alternating Hamiltonian parameters.
DEFF Research Database (Denmark)
Bhaskar, Mahajan Sagar; Padmanaban, Sanjeevikumar; Fedák, Viliam
2017-01-01
; such as a photovoltaic (PV) system with a Multilevel Inverter (MLI), electrical drives, automotive, hybrid electric cars etc. The proposed topology is derived by attaching the Cockcroft Walton (CW) multiplier to an upper L-converter of the LL topology of XY family. The mode of operation of L-LMBC with mathematical...
Uncertainty Einstein, Heisenberg, Bohr, and the struggle for the soul of science
Lindley, David
2007-01-01
The uncertainty in this delightful book refers to Heisenberg's Uncertainty Principle, an idea first postulated in 1927 by physicist Werner Heisenberg in his attempt to make sense out of the developing field of quantum mechanics. As Lindley so well explains it, the concept of uncertainty shook the philosophical underpinnings of science. It was Heisenberg's work that, to a great extent, kept Einstein from accepting quantum mechanics as a full explanation for physical reality. Similarly, it was the Uncertainty Principle that demonstrated the limits of scientific investigation: if Heisenberg is correct there are some aspects of the physical universe that are to remain beyond the reach of scientists. As he has done expertly in books like Boltzmann's Atom, Lindley brings to life a critical period in the history of science, explaining complex issues to the general reader, presenting the major players in an engaging fashion, delving into the process of scientific discovery and discussing the interaction between scien...
Energy Technology Data Exchange (ETDEWEB)
Barut, A.O. (Colorado Univ., Boulder (USA). Dept. of Physics); Oezaltin, O.; Uenal, N. (Dicle Univ., Diyarbakir (Turkey). Dept. of Physics)
1985-01-01
The Heisenberg equations for the Dirac electron in an external electromagnetic plane wave have been solved exactly in terms of incomplete ..gamma..-functions. As a special case the solution for a crossed constant electric and magnetic field is given.
Wang, Dong; Huang, Aijun; Ming, Fei; Sun, Wenyang; Lu, Heping; Liu, Chengcheng; Ye, Liu
2017-06-01
The uncertainty principle provides a nontrivial bound to expose the precision for the outcome of the measurement on a pair of incompatible observables in a quantum system. Therefore, it is of essential importance for quantum precision measurement in the area of quantum information processing. Herein, we investigate quantum-memory-assisted entropic uncertainty relation (QMA-EUR) in a two-qubit Heisenberg \\boldsymbol{X}\\boldsymbol{Y}\\boldsymbol{Z} spin chain. Specifically, we observe the dynamics of QMA-EUR in a realistic model there are two correlated sites linked by a thermal entanglement in the spin chain with an inhomogeneous magnetic field. It turns out that the temperature, the external inhomogeneous magnetic field and the field inhomogeneity can lift the uncertainty of the measurement due to the reduction of the thermal entanglement, and explicitly higher temperature, stronger magnetic field or larger inhomogeneity of the field can result in inflation of the uncertainty. Besides, it is found that there exists distinct dynamical behaviors of the uncertainty for ferromagnetism \\boldsymbol{}≤ft(\\boldsymbol{J}\\boldsymbol{0}\\right) chains. Moreover, we also verify that the measuring uncertainty is dramatically anti-correlated with the purity of the bipartite spin system, the greater purity can result in the reduction of the measuring uncertainty, vice versa. Therefore, our observations might provide a better understanding of the dynamics of the entropic uncertainty in the Heisenberg spin chain, and thus shed light on quantum precision measurement in the framework of versatile systems, particularly solid states.
Thermally driven classical Heisenberg model in 1D with a local time varying field
Bagchi, Debarshee
2013-12-01
We study thermal transport in the one-dimensional classical Heisenberg model driven by boundary heat baths and in the presence of a local time varying magnetic field. We find that, in the steady state, the energy current shows thermal resonance as the frequency of the time-periodic forcing is varied. Even in the absence of a thermal bias a steady nonzero energy current can be induced in the system, whereas for the thermally driven system a current reversal can be achieved in the bulk by suitably tuning the system parameters. When the amplitude of the forcing field is increased the system exhibits multiple resonance peaks. Thermal resonance survives in the thermodynamic limit and their magnitude increases as the temperature of the system is decreased. We find that the resonance frequency is an intrinsic frequency of the model and is related to its spin wave dispersion spectrum. Finally we show that, similar to other generic force-driven systems, there is no thermal pumping despite the current reversal in the bulk of the system.
Potential energy landscape of the two-dimensional XY model: Higher-index stationary points
Mehta, D.; Hughes, C.; Kastner, M.; Wales, D. J.
2014-06-01
The application of numerical techniques to the study of energy landscapes of large systems relies on sufficient sampling of the stationary points. Since the number of stationary points is believed to grow exponentially with system size, we can only sample a small fraction. We investigate the interplay between this restricted sample size and the physical features of the potential energy landscape for the two-dimensional XY model in the absence of disorder with up to N = 100 spins. Using an eigenvector-following technique, we numerically compute stationary points with a given Hessian index I for all possible values of I. We investigate the number of stationary points, their energy and index distributions, and other related quantities, with particular focus on the scaling with N. The results are used to test a number of conjectures and approximate analytic results for the general properties of energy landscapes.
Performance Characterization of an xy-Stage Applied to Micrometric Laser Direct Writing Lithography
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Juan Jaramillo
2017-01-01
Full Text Available This article concerns the characterization of the stability and performance of a motorized stage used in laser direct writing lithography. The system was built from commercial components and commanded by G-code. Measurements use a pseudo-periodic-pattern (PPP observed by a camera and image processing is based on Fourier transform and phase measurement methods. The results report that the built system has a stability against vibrations determined by peak-valley deviations of 65 nm and 26 nm in the x and y directions, respectively, with a standard deviation of 10 nm in both directions. When the xy-stage is in movement, it works with a resolution of 0.36 μm, which is an acceptable value for most of research and development (R and D microtechnology developments in which the typical feature size used is in the micrometer range.
A Hardy Inequality with Remainder Terms in the Heisenberg Group and the Weighted Eigenvalue Problem
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Zixia Yuan
2007-12-01
Full Text Available Based on properties of vector fields, we prove Hardy inequalities with remainder terms in the Heisenberg group and a compact embedding in weighted Sobolev spaces. The best constants in Hardy inequalities are determined. Then we discuss the existence of solutions for the nonlinear eigenvalue problems in the Heisenberg group with weights for the p-sub-Laplacian. The asymptotic behaviour, simplicity, and isolation of the first eigenvalue are also considered.
A Hardy Inequality with Remainder Terms in the Heisenberg Group and the Weighted Eigenvalue Problem
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Dou Jingbo
2007-01-01
Full Text Available Based on properties of vector fields, we prove Hardy inequalities with remainder terms in the Heisenberg group and a compact embedding in weighted Sobolev spaces. The best constants in Hardy inequalities are determined. Then we discuss the existence of solutions for the nonlinear eigenvalue problems in the Heisenberg group with weights for the -sub-Laplacian. The asymptotic behaviour, simplicity, and isolation of the first eigenvalue are also considered.
Modified Heisenberg model for the zig-zag structure in multiferroic RMn{sub 2}O{sub 5}
Energy Technology Data Exchange (ETDEWEB)
Bahoosh, Safa Golrokh, E-mail: safa.bahoosh@uni-konstanz.de [Department of Physics, University of Konstanz, D-78457 Konstanz (Germany); Wesselinowa, Julia M., E-mail: julia@phys.uni-sofia.bg [Department of Physics, University of Sofia, 1164 Sofia (Bulgaria); Trimper, Steffen, E-mail: steffen.trimper@physik.uni-halle.de [Institute of Physics, Martin-Luther-University Halle-Wittenberg, D-06099 Halle (Germany)
2015-08-28
The class of RMn{sub 2}O{sub 5} (R = Ho, Tb, Y, Eu) compounds offers multiferroic properties where the refined magnetic zig-zag order breaks the inversion symmetry. Varying the temperature, the system undergoes a magnetic and a subsequent ferroelectric phase transition where the ferroelectricity is magnetically induced. We propose a modified anisotropic Heisenberg model that can be used as a tractable analytical model studying the properties of those antiferromagnetic zig-zag spin chains. Based on a finite temperature Green's function method, it is shown that the polarization is induced solely by different exchange couplings of the two different Mn{sup 4+} and Mn{sup 3+} magnetic ions. We calculate the excitation energy of the spin system for finite temperatures, which for its part determines the temperature dependent magnetization and polarization. The ferroelectric phase transition is manifested as a kink in the excitation energy. The variation of the polarization by an external magnetic field depends strongly on the direction of that field. Whereas, the polarization in b-direction increases with an external magnetic field as well in b-direction it can be switched for strong fields in a-direction. The results based on that modified Heisenberg model are in qualitative agreement with experimental data.
Graphical Representation of Complex Solutions of the Quadratic Equation in the "xy" Plane
McDonald, Todd
2006-01-01
This paper presents a visual representation of complex solutions of quadratic equations in the xy plane. Rather than moving to the complex plane, students are able to experience a geometric interpretation of the solutions in the xy plane. I am also working on these types of representations with higher order polynomials with some success.
Etude morphologique d'un cas de femme XY avec dysgénésie ...
African Journals Online (AJOL)
Mots clés : Etude morphologique, femme XY, dysgénésie gonadique pure. The authors describe the morphological features of a twenty years old female, without ambiguous genitalia, presenting a 46,XY karyotype, normal female external genitalia and gonadal dysgenesis. She has an android type of morpho dysplasia and ...
DEFF Research Database (Denmark)
Berglund, Agnethe; Johannsen, Trine H; Stochholm, Kirstine
2017-01-01
the general population. Interventions: None. Main outcome measures: combined mortality and morbidity as well as chapter-specific morbidity. Medicinal use and socioeconomic profile, including education, cohabitation and retirement. Results: Compared to female controls overall morbidity was increased in XY.......05-0.18) were reduced in XY females but educational level (HR=0.92, CI: 0.61-1.37) was similar to controls. Income diverged during life with XY females having respectively a lower and higher income in the younger and older years. Conclusions: Morbidity was not increased in XY females when disregarding diagnoses...... closely related to the DSD condition. Judged on educational level and income XY females perform well on the labor market. However, DSD seems to impact on the prospects of family life.....
Boltzmann sampling for an XY model using a non-degenerate optical parametric oscillator network
Takeda, Y.; Tamate, S.; Yamamoto, Y.; Takesue, H.; Inagaki, T.; Utsunomiya, S.
2018-01-01
We present an experimental scheme of implementing multiple spins in a classical XY model using a non-degenerate optical parametric oscillator (NOPO) network. We built an NOPO network to simulate a one-dimensional XY Hamiltonian with 5000 spins and externally controllable effective temperatures. The XY spin variables in our scheme are mapped onto the phases of multiple NOPO pulses in a single ring cavity and interactions between XY spins are implemented by mutual injections between NOPOs. We show the steady-state distribution of optical phases of such NOPO pulses is equivalent to the Boltzmann distribution of the corresponding XY model. Estimated effective temperatures converged to the setting values, and the estimated temperatures and the mean energy exhibited good agreement with the numerical simulations of the Langevin dynamics of NOPO phases.
Quantum chromodynamics, antiferromagnets and XY models from a unified point of view
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Christoph P. Hofmann
2017-03-01
Full Text Available Antiferromagnets and quantum XY magnets in three space dimensions are described by an effective Lagrangian that exhibits the same structure as the effective Lagrangian of quantum chromodynamics with two light flavors. These systems all share a spontaneously broken internal symmetry O(N→O(N−1. Although the respective scales differ by many orders of magnitude, the general structure of the low-temperature expansion of the partition function is the same. In the nonabelian case (N≥3, logarithmic terms of the form T8lnT emerge at three-loop order, while for N=2 the series only involves powers of T2. The manifestation of the Goldstone boson interaction in the pressure, order parameter, and susceptibility is explored in presence of an external field.
Zhang, Guo-Qing; Xu, Jing-Bo
2017-06-01
We investigate the quantum coherence of an XY spin chain with Dzyaloshinskii-Moriya interaction using a quantum renormalization group-based method, and show that the relative entropy of coherence increases with Dzyaloshinskii-Moriya interaction strength at zero temperature, as well as at finite temperature. We also study the quantum criticality of the system by making use of the relative entropy of coherence and violation of Bell inequality, and find that the first derivatives of the renormalized quantum coherence exhibit singularity near the critical point of the quantum phase transition. Finally, we explore the finite-size scaling behaviors of the derivatives of the quantum coherence at the critical point of the quantum phase transition, and obtain several universal finite-size scaling laws.
{Γ} -Convergence Analysis of a Generalized XY Model: Fractional Vortices and String Defects
Badal, Rufat; Cicalese, Marco; De Luca, Lucia; Ponsiglione, Marcello
2017-11-01
We propose and analyze a generalized two dimensional XY model, whose interaction potential has n weighted wells, describing corresponding symmetries of the system. As the lattice spacing vanishes, we derive by {Γ} -convergence the discrete-to-continuum limit of this model. In the energy regime we deal with, the asymptotic ground states exhibit fractional vortices, connected by string defects. The {Γ} -limit takes into account both contributions, through a renormalized energy, depending on the configuration of fractional vortices, and a surface energy, proportional to the length of the strings. Our model describes in a simple way several topological singularities arising in Physics and Materials Science. Among them, disclinations and string defects in liquid crystals, fractional vortices and domain walls in micromagnetics, partial dislocations and stacking faults in crystal plasticity.
A Marfan Syndrome Case of 46,XY,(8;20(q2;q13 Chromosome Structure
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Diclehan Oral
2006-01-01
Full Text Available The Marfan syndrome is an inherited, autosomal dominant disorder that affects the skeletal, ocular and cardiovascular systems. The patient had clinical diagnosis of Marfan syndrome in the Department of Endocrinology. Chromosome analysis was performed on a case referred to Genetic Laboratory of Medical Biology Department with pre-diagnosis of Marfan syndrome. For chromosome analysis, peripheral blood culture was performed. The preparates were stained by Giemsa Technique (GTG, and 25 cells were counted. Twenty metaphase chromosomes were karyotyped, and 46,XY,t(8;20(q2;q13 karyotype was identified in the case . As a result of analysis, his parents were found to have normal karyotype, thus, it was concluded that the translocation in our case is de novo.
Cardiovascular pathology in males and females with 45,X/46,XY mosaicism.
De Groote, Katya; Cools, Martine; De Schepper, Jean; Craen, Margarita; François, Inge; Devos, Daniel; Carbonez, Karlien; Eyskens, Benedicte; De Wolf, Daniel
2013-01-01
The phenotype of 45,X/46,XY mosaicism is heterogeneous ranging from females with Turner syndrome (TS) to apparently normal males. Males with 45,X/46,XY frequently show stigmata typically associated with TS. We hypothesised that males with 45,X/46,XY have similar cardiovascular pathology as females with 45,X/46,XY. To investigate cardiovascular abnormalities in 45,X/46,XY males and to compare them with 45,X/46,XY females. Patients with 45,X/46,XY mosaicism were selected from the Belgian Registry for Growth and Puberty problems and via the multidisciplinary clinic for disorders of sexual development. EIGHTEEN PATIENTS WERE INCLUDED: 8 raised as females (F) and 10 as males (M). Complete cardiac examination with blood pressure measurement, ECG, echocardiography and MRI. Cardiac parameters were registered for both groups. In a second phase, clinical features and external masculinisation score (EMS) were retrospectively collected from the medical files. A structural heart defect was diagnosed before inclusion in 1 F with coarctation and 1 M with spontaneously closed VSD. A bicuspid aortic valve was found in 8 (3 F, 5 M). Dilation of the ascending aorta was present in 4 M and was severe in 2 young boys. QTc was prolonged in 3 F and 2 M. Males with 45,X/46,XY mosaicism have similar cardiovascular pathology as 45,X/46,XY females. Dilation of the ascending aorta can be important, also in males. We advise cardiac screening and life-long monitoring in all males with 45,X/46,XY mosaicism according to the existing guidelines for Turner syndrome.
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Jimmy Linggarjati
2007-05-01
Full Text Available The objective of the research was to produce a drawing table system with 2-aksis XY-table method and EMCsoftware implementation. The EMC (Enhanced Machine Control features are integrated with L297 and L298 as a motorstepper driver to draw simple objects. Methods used in the research are library research, engineering, and laboratory.The results concluded that system can work properly to draw objects such as square, triangle, circle, and capital lettersA-Z according to the given input.
Dynamic scaling of the restoration of rotational symmetry in Heisenberg quantum antiferromagnets
Weinberg, Phillip; Sandvik, Anders W.
2017-08-01
We apply imaginary-time evolution with the operator e-τ H to study relaxation dynamics of gapless quantum antiferromagnets described by the spin-rotation-invariant Heisenberg Hamiltonian H . Using quantum Monte Carlo simulations to obtain unbiased results, we propagate an initial state with maximal order parameter msz (the staggered magnetization) in the z spin direction and monitor the expectation value 〈ms〉 as a function of imaginary time τ . Results for different system sizes (lengths) L exhibit an initial essentially size independent relaxation of 〈ms〉 toward its value in the infinite-size spontaneously symmetry broken state, followed by a strongly size dependent final decay to zero when the O (3 ) rotational symmetry of the order parameter is restored. We develop a generic finite-size scaling theory that shows the relaxation time diverges asymptotically as Lz, where z is the dynamic exponent of the low-energy excitations. We use the scaling theory to develop a practical way of extracting the dynamic exponent from the numerical finite-size data, systematically eliminating scaling corrections. We apply the method to spin-1 /2 Heisenberg antiferromagnets on two different lattice geometries: the standard two-dimensional (2D) square lattice and a site-diluted 2D square lattice at the percolation threshold. In the 2D case we obtain z =2.001 (5 ) , which is consistent with the known value z =2 , while for the site-diluted lattice we find z =3.90 (1 ) or z =2.056 (8 ) Df , where Df=91 /48 is the fractal dimensionality of the percolating system. This is an improvement on previous estimates of z ≈3.7 . The scaling results also show a fundamental difference between the two cases; for the 2D square lattice, the data can be collapsed onto a common scaling function even when 〈ms〉 is relatively large, reflecting the Anderson tower of quantum rotor states with a common dynamic exponent z =2 . For the diluted 2D square lattice, the scaling works well only for
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R Afzali
2013-03-01
Full Text Available Because the key issue in quantum information and quantum computing is entanglement, the investigation of the effects of environment, as a source of quantum dissipation, and interaction between environment and system on entanglement and quantum phase transition is important. In this paper, we consider two-qubit system in the anisotropic Heisenberg XXZ model with the Dzyaloshinskii-moriya interaction, and accompanied quantum dissipation. Using Lindblad dynamics, the coupling effect and also temperature effect on concurrence, as a measure of entanglement of system, is obtained. The role of DM interaction parameters in the evolution of entanglement is investigated. Furthermore, using derivative of concurrence, the effects of dissipation and DM interaction parameter on quantum phase transition are obtained. It should be noted that spin-orbit interaction or DM parameter intensively influence the process of impressments of dissipation on entanglement measure and quantum phase transition. The current research is very important in the topics of nanometric systems.
Thermodynamics of the antiferromagnetic Heisenberg model on the checkerboard lattice
Khatami, Ehsan; Rigol, Marcos
2011-04-01
Employing numerical linked-cluster expansions (NLCEs) along with exact diagonalizations of finite clusters with periodic boundary condition, we study the energy, specific heat, entropy, and various susceptibilities of the antiferromagnetic Heisenberg model on the checkerboard lattice. NLCEs, combined with extrapolation techniques, allow us to access temperatures much lower than those accessible to exact diagonalization and other series expansions. We show that the high-temperature peak in specific heat decreases as the frustration increases, consistent with the large amount of unquenched entropy in the region around maximum classical frustration, where the nearest-neighbor and next-nearest-neighbor exchange interactions (J and J', respectively) have the same strength, and with the formation of a second peak at lower temperatures. The staggered susceptibility shows a change of character when J' increases beyond 0.75J, implying the disappearance of the antiferromagnetic order at low temperatures. For J'=4J, in the limit of weakly coupled crossed chains, we find large susceptibilities for stripe and Néel order with Q=(π/2,π/2) at intermediate temperatures. Other magnetic and bond orderings, such as a plaquette valence-bond solid and a crossed-dimer order suggested by previous studies, are also investigated.
Stapp's quantum dualism: The James and Heisenberg model of consciousness
Noyes, H. P.
1994-02-01
Henry Stapp attempts to resolve the Cartesian dilemma by introducing what the author would characterize as an ontological dualism between mind and matter. His model for mind comes from William James' description of conscious events and for matter from Werner Heisenberg's ontological model for quantum events (wave function collapse). His demonstration of the isomorphism between the two types of events is successful, but in the author's opinion fails to establish a monistic, scientific theory. The author traces Stapp's failure to his adamant rejection of arbitrariness, or 'randomness.' This makes it impossible for him (or for Bohr and Pauli before him) to understand the power of Darwin's explanation of biology, let alone the triumphs of modern 'neo-Darwinism.' The author notes that the point at issue is a modern version of the unresolved opposition between Leucippus and Democritus on one side and Epicurus on the other. Stapp's views are contrasted with recent discussions of consciousness by two eminent biologists: Crick and Edelman. They locate the problem firmly in the context of natural selection on the surface of the earth. Their approaches provide a sound basis for further scientific work. The author briefly examines the connection between this scientific (rather than ontological) framework and the new fundamental theory based on bit-strings and the combinatorial hierarchy.
Reducing Uncertainty: Implementation of Heisenberg Principle to Measure Company Performance
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Anna Svirina
2015-08-01
Full Text Available The paper addresses the problem of uncertainty reduction in estimation of future company performance, which is a result of wide range of enterprise's intangible assets probable efficiency. To reduce this problem, the paper suggests to use quantum economy principles, i.e. implementation of Heisenberg principle to measure efficiency and potential of intangible assets of the company. It is proposed that for intangibles it is not possible to estimate both potential and efficiency at a certain time point. To provide a proof for these thesis, the data on resources potential and efficiency from mid-Russian companies was evaluated within deterministic approach, which did not allow to evaluate probability of achieving certain resource efficiency, and quantum approach, which allowed to estimate the central point around which the probable efficiency of resources in concentrated. Visualization of these approaches was performed by means of LabView software. It was proven that for tangible assets performance estimation a deterministic approach should be used; while for intangible assets the quantum approach allows better quality of future performance prediction. On the basis of these findings we proposed the holistic approach towards estimation of company resource efficiency in order to reduce uncertainty in modeling company performance.
Magnon-induced nuclear relaxation in the quantum critical region of a Heisenberg linear chain
Hoch, M. J. R.
2017-07-01
The low-temperature properties of spin-1/2 one-dimensional (1D) Heisenberg antiferromagnetic (HAF) chains which have relatively small exchange couplings between the spins can be tuned using laboratory-scale magnetic fields. Magnetization measurements, made as a function of temperature, provide phase diagrams for these systems and establish the quantum critical point (QCP). The evolution of the spin dynamics behavior with temperature and applied field in the quantum critical (QC) region, near the QCP, is of particular interest and has been experimentally investigated in a number of 1D HAFs using neutron scattering and nuclear magnetic resonance as the preferred techniques. In the QC phase both quantum and thermal spin fluctuations are present. As a result of extended spin correlations in the chains, magnon excitations are important at finite temperatures. An expression for the NMR spin-lattice relaxation rate 1 /T1 of probe nuclei in the QC phase of 1D HAFs is obtained by considering Raman scattering processes which induce nuclear spin flips. The relaxation rate expression, which involves the temperature and the chemical potential, predicts scaling behavior of 1 /T1 consistent with recent experimental findings for quasi-1D HAF systems. A simple relationship between 1 /T1 and the deviation of the magnetization from saturation (MS-M ) is predicted for the QC region.
Thermodynamic limit of particle-hole form factors in the massless XXZ Heisenberg chain
Energy Technology Data Exchange (ETDEWEB)
Kitanine, N. [Univ. de Bourgogne (France). IMB, UMR 5584 du CNRS; Kozlowski, K.K. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Maillet, J.M.; Terras, V. [ENS Lyon (France). UMR 5672 du CNRS, Lab. de Physique; Slavnov, N.A. [Steklov Mathematical Inst., Moscow (Russian Federation)
2011-03-15
We study the thermodynamic limit of the particle-hole form factors of the XXZ Heisenberg chain in the massless regime. We show that, in this limit, such form factors decrease as an explicitly computed power-law in the system size. Moreover, the corresponding amplitudes can be obtained as a product of a ''smooth'' and a ''discrete'' part: the former depends continuously on the rapidities of the particles and holes, whereas the latter has an additional explicit dependence on the set of integer numbers that label each excited state in the associated logarithmic Bethe equations. We also show that special form factors corresponding to zero-energy excitations lying on the Fermi surface decrease as a power-law in the system size with the same critical exponents as in the longdistance asymptotic behavior of the related two-point correlation functions. The methods we develop in this article are rather general and can be applied to other massless integrable models associated to the six-vertex R-matrix and having determinant representations for their form factors. (orig.)
Berglund, Agnethe; Johannsen, Trine H; Stochholm, Kirstine; Viuff, Mette H; Fedder, Jens; Main, Katharina M; Gravholt, Claus H
2016-12-01
The prevalence of phenotypic females with a 46,XY karyotype is low, thus current knowledge about age and clinical presentation at diagnosis is sparse even for the most frequent conditions, androgen insensitivity syndrome (AIS), and gonadal dysgenesis. To estimate incidence, prevalence, age at diagnosis, and clinical presentation at diagnosis in 46,XY females. A nationwide study covering all known females with a 46,XY karyotype in Denmark since 1960. The diagnosis of 46,XY disorder of sex development (DSD) was determined by medical record evaluation, data from the Danish National Patient Registry, and genetic testing, if available. A total of 166 females registered as 46,XY females in the Danish Cytogenetic Central Registry were identified. A total of 124 females were classified as having 46,XY DSD, 78 with AIS and 25 with gonadal dysgenesis, whereas the remaining subjects had a variety of different diagnoses. The prevalence of 46,XY females was 6.4 per 100 000 live born females, and for AIS and gonadal dysgenesis, it was 4.1 and 1.5 per 100 000, respectively. Median age at diagnosis was 7.5 years (95% confidence interval, 4.0-13.5; range, 0-34 y) in AIS and 17.0 years (95% confidence interval, 15.5-19.0; range, 0-28 y) in gonadal dysgenesis (P = .001). Clinical presentation was dependent on cause of DSD. The first estimate on prevalence of 46,XY females is 6.4 per 100 000 live born females. The presentation of AIS and gonadal dysgenesis is distinctly different, with AIS being diagnosed during childhood and gonadal dysgenesis during pubertal years. The presenting phenotype is dependent on the cause of 46,XY DSD.
Thermodynamic behavior of the XXZ Heisenberg s = 1/2 chain around the factorizing magnetic field.
Abouie, J; Langari, A; Siahatgar, M
2010-06-02
We have investigated the zero-and finite-temperature behaviors of the anisotropic antiferromagnetic Heisenberg XXZ spin-1/2 chain in the presence of a transverse magnetic field (h). The attention is concentrated on an interval of magnetic field between the factorizing field (h(f)) and the critical one (h(c)). The model presents a spin-flop phase for 0 entanglement phase transition at h = h(f). The entanglement estimators clearly show that the entanglement is lost exactly at h = h(f), which justifies different quantum correlations on both sides of the factorizing field. As a consequence of zero entanglement (at h = h(f)) the ground state is known exactly as a product of single-particle states which is the starting point for initiating a spin wave theory. The linear spin wave theory is implemented to obtain the specific heat and thermal entanglement of the model in the interested region. A double-peak structure is found in the specific heat around h = h(f), which manifests the existence of two energy scales in the system as a result of two competing orders before the critical point. These results are confirmed by the low temperature Lanczos data which we have computed.
Petersen, Jakob; Pollak, Eli
2015-12-14
One of the challenges facing on-the-fly ab initio semiclassical time evolution is the large expense needed to converge the computation. In this paper, we suggest that a significant saving in computational effort may be achieved by employing a semiclassical initial value representation (SCIVR) of the quantum propagator based on the Heisenberg interaction representation. We formulate and test numerically a modification and simplification of the previous semiclassical interaction representation of Shao and Makri [J. Chem. Phys. 113, 3681 (2000)]. The formulation is based on the wavefunction form of the semiclassical propagation instead of the operator form, and so is simpler and cheaper to implement. The semiclassical interaction representation has the advantage that the phase and prefactor vary relatively slowly as compared to the "standard" SCIVR methods. This improves its convergence properties significantly. Using a one-dimensional model system, the approximation is compared with Herman-Kluk's frozen Gaussian and Heller's thawed Gaussian approximations. The convergence properties of the interaction representation approach are shown to be favorable and indicate that the interaction representation is a viable way of incorporating on-the-fly force field information within a semiclassical framework.
Quantum entanglement and criticality of the antiferromagnetic Heisenberg model in an external field
Liu, Guang-Hua; Li, Ruo-Yan; Tian, Guang-Shan
2012-06-01
By Lanczos exact diagonalization and the infinite time-evolving block decimation (iTEBD) technique, the two-site entanglement as well as the bipartite entanglement, the ground state energy, the nearest-neighbor correlations, and the magnetization in the antiferromagnetic Heisenberg (AFH) model under an external field are investigated. With increasing external field, the small size system shows some distinct upward magnetization stairsteps, accompanied synchronously with some downward two-site entanglement stairsteps. In the thermodynamic limit, the two-site entanglement, as well as the bipartite entanglement, the ground state energy, the nearest-neighbor correlations, and the magnetization are calculated, and the critical magnetic field hc = 2.0 is determined exactly. Our numerical results show that the quantum entanglement is sensitive to the subtle changing of the ground state, and can be used to describe the magnetization and quantum phase transition. Based on the discontinuous behavior of the first-order derivative of the entanglement entropy and fidelity per site, we think that the quantum phase transition in this model should belong to the second-order category. Furthermore, in the magnon existence region (h behavior of block entanglement which can be described by a free bosonic field theory is observed, and the central charge c is determined to be 1.
Quantum entanglement and criticality of the antiferromagnetic Heisenberg model in an external field.
Liu, Guang-Hua; Li, Ruo-Yan; Tian, Guang-Shan
2012-06-27
By Lanczos exact diagonalization and the infinite time-evolving block decimation (iTEBD) technique, the two-site entanglement as well as the bipartite entanglement, the ground state energy, the nearest-neighbor correlations, and the magnetization in the antiferromagnetic Heisenberg (AFH) model under an external field are investigated. With increasing external field, the small size system shows some distinct upward magnetization stairsteps, accompanied synchronously with some downward two-site entanglement stairsteps. In the thermodynamic limit, the two-site entanglement, as well as the bipartite entanglement, the ground state energy, the nearest-neighbor correlations, and the magnetization are calculated, and the critical magnetic field h(c) = 2.0 is determined exactly. Our numerical results show that the quantum entanglement is sensitive to the subtle changing of the ground state, and can be used to describe the magnetization and quantum phase transition. Based on the discontinuous behavior of the first-order derivative of the entanglement entropy and fidelity per site, we think that the quantum phase transition in this model should belong to the second-order category. Furthermore, in the magnon existence region (h entanglement which can be described by a free bosonic field theory is observed, and the central charge c is determined to be 1.
Atanasov, Victor; Saxena, Avadh
2011-05-04
Adopting a purely two-dimensional relativistic equation for graphene's carriers contradicts the Heisenberg uncertainty principle since it requires setting the off-the-surface coordinate of a three-dimensional wavefunction to zero. Here we present a theoretical framework for describing graphene's massless relativistic carriers in accordance with this most fundamental of all quantum principles. A gradual confining procedure is used to restrict the dynamics onto a surface and normal to the surface parts, and in the process the embedding of this surface into the three-dimensional world is accounted for. As a result an invariant geometric potential arises in the surface part which scales linearly with the mean curvature and shifts the Fermi energy of the material proportional to bending. Strain induced modification of the electronic properties or 'straintronics' is clearly an important field of study in graphene. This opens an avenue to producing electronic devices: micro- and nano-electromechanical systems (MEMS and NEMS), where the electronic properties are controlled by geometric means and no additional alteration of graphene is necessary. The appearance of this geometric potential also provides us with clues as to how quantum dynamics looks in the curved space-time of general relativity. In this context we explore a two-dimensional cross-section of the wormhole geometry, realized with graphene as a solid state thought experiment. © 2011 IOP Publishing Ltd
McLeod, David; McLeod, Roger
2008-04-01
The electron model used in our other joint paper here requires revision of some foundational physics. That electron model followed from comparing the experimentally proved results of human vision models using spatial Fourier transformations, SFTs, of pincushion and Hermann grids. Visual systems detect ``negative'' electric field values for darker so-called ``illusory'' diagonals that are physical consequences of the lens SFT of the Hermann grid, distinguishing this from light ``illusory'' diagonals. This indicates that oppositely directed vectors of the separate illusions are discretely observable, constituting another foundational fault in quantum mechanics, QM. The SFT of human vision is merely the scaled SFT of QM. Reciprocal space results of wavelength and momentum mimic reciprocal relationships between space variable x and spatial frequency variable p, by the experiment mentioned. Nobel laureate physicist von B'ek'esey, physiology of hearing, 1961, performed pressure input Rect x inputs that the brain always reports as truncated Sinc p, showing again that the brain is an adjunct built by sight, preserves sign sense of EMF vectors, and is hard wired as an inverse SFT. These require vindication of Schr"odinger's actual, but incomplete, wave model of the electron as having physical extent over the wave, and question Heisenberg's uncertainty proposal.
Directory of Open Access Journals (Sweden)
U. Löw
2009-01-01
Full Text Available The magnetic properties of the two-dimensional S=1/2 (quantum antiferromagnetic Heisenberg model on a honeycomb lattice with and without interlayer coupling are studied by means of a continuous Euclidean time Quantum Monte-Carlo algorithm. The internal energy, the magnetic susceptibility and the staggered magnetization are determined in the full temperature range. For the two-dimensional system the ground-state energy/bond is found to be E0hc=-0.36303(13, and the zero temperature staggered magnetization mst=0.2681(8. For coupled planes of honeycomb systems a phase transition from an ordered phase to a disordered phase is found at T/J=0.695(10.
Solano-Carrillo, E.; Franco, R.; Silva-Valencia, J.
2011-06-01
We study the ground-state and thermal entanglement in the mixed-spin (S,s)=(1,1/2) Heisenberg chain with single-ion anisotropy D using exact diagonalization of small clusters. In this system, a quantum phase transition is revealed to occur at the value D=0, which is the bifurcation point for the global ground state; that is, when the single-ion anisotropy energy is positive, the ground state is unique, whereas when it is negative, the ground state becomes doubly degenerate and the system has the ferrimagnetic long-range order. Using the negativity as a measure of entanglement, we find that a pronounced dip in this quantity, taking place just at the bifurcation point, serves to signal the quantum phase transition. Moreover, we show that the single-ion anisotropy helps to improve the characteristic temperatures above which the quantum behavior disappears.
[XY gonadal dysgenesis with female phenotype (author's transpl)].
Trias, J V; Martínez, F B
1975-01-01
In this paper, we are dealing with the study of a case of multiple somatic malformations, with external female genitals and 46 XY caryotype. The anatomical and histological study of the genital organs, allows us to verify the existence of internal genital organs; consisting essentially in tubes, bicornous uterus, a gonadal ligament in a normotopical position, Wolffian remains and the absence of a vagina. The external female genitals are completely normal. When we interpreted these findings, we paid special attention to the relation existing between the abnormal presence of the Wolffian remains, male genotype, and typical female genital structures. Taking account of the latest scientific advances concerning genital development, we considered the possibility of the existence of secretions of a "masculinizing" substance from the gonad, before its morphological differentiation, which was interrupted by an etiological undetermined noxa. When this evolution was arrested, together with the secretions of the masculinizing substance, the genital development continued normally for a female. The terminal teratogenic period for this malformation is situated from the 5th to the 6th week of gestation (human embryos from 11 to 14 mm., Streeter Horizon XVII).
Thermodynamics and phase transitions of the pinwheel-distorted Kagome lattice Heisenberg model
Khatami, Ehsan; Singh, Rajiv R. P.; Rigol, Marcos
2012-02-01
We study the Heisenberg model on the pinwheel-distorted Kagome lattice as observed in the material Rb2Cu3SnF12. Experimentally relevant thermodynamic properties at finite temperatures are computed utilizing numerical linked-cluster expansions [1]. We introduce a Lanczos-based zero-temperature numerical linked-cluster expansion and study the approach of the pinwheel distorted lattice to the uniform Kagome lattice Heisenberg model. We find strong evidence for a phase transition before the uniform limit is reached, implying that the ground state of the Kagome lattice Heisenberg model is likely not pinwheel dimerized and is stable to finite pinwheel dimerizing perturbations [2]. [4pt] [1] M. Rigol and R. R. P. Singh, Phys. Rev. Lett. 98, 207204 (2007); Phys. Rev. B 76, 184403 (2007). [0pt] [2] E. Khatami, R. R. P. Singh, M. Rigol, preprint: arXiv:1105.4147
Gonadoblastoma with Dysgerminoma in a Phenotypically Turner-Like Girl with 45,X/46,XY Karyotype.
Yüce, Özge; Döğer, Esra; Çelik, Nurullah; Emeksiz, Hamdi Cihan; Çamurdan, Mahmut Orhun; Bideci, Aysun; Cinaz, Peyami
2015-12-01
Individuals with 45,X/46,XY karyotype are at increased risk for germ cell tumor development. We report a case with a diagnosis of 45,X/46,XY gonadal dysgenesis who presented with short stature, physical stigmata of Turner syndrome. Her pubertal development was at Tanner stage 3. At follow-up, bilateral prophylactic gonadectomy was performed when considering the risk factors. Pathological assessment was consistent with gonadoblastoma in the left gonad, and dysgerminoma and gonadoblastoma in neighboring areas in the right gonad. The karyotype analysis of the right and left gonadal tissues reveled 45,X[97,3]/46,XY[2,7] and 45,X[92,7]/46,XY[4,5]/47,XYY [2,8] mosaic, respectively. The clinical management of such patient should be individualized according to the present risk factors. Additionally, signs of estrogenization like advanced breast development always suggest the possible presence of germ cell tumor.
Novel LY Converter Topologies for High Gain Transfer Ratio - A New Breed of XY Family
DEFF Research Database (Denmark)
Bhaskar, M.S.; Padmanaban, S.; Kulkarni, R.
2016-01-01
New LY converter topologies of DC-DC XY family for renewable energy applications are articulated in this paper. Four LY topologies are presented in this paper and the proposed topologies provide an operative solution for renewable energy applications which requires a very high inverting voltage...... consistently showed good conformity with theoretical analysis and also validates the functionality of the proposed LY converter topologies of the XY converter family....
Partition functions of classical Heisenberg spin chains with arbitrary and different exchange
Energy Technology Data Exchange (ETDEWEB)
Cregg, P J [Materials Characterisation and Processing Group, Waterford Institute of Technology, Waterford (Ireland); GarcIa-Palacios, J L [Instituto de Ciencia de Materiales de Aragon, Consejo Superior de Investigaciones Cientificas-Universidad de Zaragoza, 50009 Zaragoza (Spain); Svedlindh, P [Department of Engineering Sciences, Uppsala University, Box 534, SE-751 21 Uppsala (Sweden)], E-mail: pjcregg@wit.ie
2008-10-31
The classical Heisenberg model has been effective in modelling exchange interactions in molecular magnets. In this model, the partition function is important as it allows the calculation of the magnetization and susceptibility. For an ensemble of N-spin sites, this typically involves integrals in 2N dimensions. Here, for two-, three- and four-spin nearest neighbour open linear Heisenberg chains these integrals are reduced to sums of known functions, using a result due to Gegenbauer. For the case of the three- and four-spin chains, the sums are equivalent in form to the results of Joyce. The general result for an N-spin chain is also obtained.
Critical behavior of the Heisenberg ferromagnets EuO and EuS
DEFF Research Database (Denmark)
Als-Nielsen, Jens Aage; Dietrich, O.W.; Kunnmann, W.
1971-01-01
Neutron-scattering measurements have been made of the critical parameters of the simple Heisenberg ferromagnets EuO and EuS. Values of the critical exponents β and ν and the amplitudes of B and F describing, respectively, the reduced magnetization and the inverse correlation range (above Tc......) are in good accord with theory. The measured values of the exponent γ, describing the static susceptibility, support the recent prediction that γ≈1.40 in a simple nearest-neighbor Heisenberg ferromagnet. The scaling relation between β, ν, and γ is fulfilled...
Emergent Power-Law Phase in the 2D Heisenberg Windmill Antiferromagnet: A Computational Experiment
Jeevanesan, Bhilahari; Chandra, Premala; Coleman, Piers; Orth, Peter P.
2015-10-01
In an extensive computational experiment, we test Polyakov's conjecture that under certain circumstances an isotropic Heisenberg model can develop algebraic spin correlations. We demonstrate the emergence of a multispin U(1) order parameter in a Heisenberg antiferromagnet on interpenetrating honeycomb and triangular lattices. The correlations of this relative phase angle are observed to decay algebraically at intermediate temperatures in an extended critical phase. Using finite-size scaling we show that both phase transitions are of the Berezinskii-Kosterlitz-Thouless type, and at lower temperatures we find long-range Z6 order.
Partial deletion of DMRT1 causes 46,XY ovotesticular disorder of sexual development.
Ledig, Susanne; Hiort, Olaf; Wünsch, Lutz; Wieacker, Peter
2012-07-01
Ovotesticular disorder of sexual development (DSD) is an unusual form of DSD, characterized by the coexistence of testicular and ovarian tissue in the same individual. In a subset of patients, ovotesticular DSD is caused by 46,XX/46,XY chimerism or mosaicism. To date, only a few monogenetic causes are known to be associated with XX and XY ovotesticular DSD. Clinical, hormonal, and histopathological data, and results of high-resolution array-comparative genomic hybridization (CGH) were obtained from a female patient with 46,XY ovotesticular DSD with testicular tissue on one side and an ovary harboring germ cells on the other. Results obtained by array-CGH were confirmed by RT-quantitative PCR. We detected a deletion of ∼35 kb affecting exons 3 and 4 of the DMRT1 gene in a female patient with 46,XY ovotesticular DSD. To the best of our knowledge, this is the smallest deletion affecting DMRT1 presented to this point in time. We suggest that haploinsufficiency of DMRT1 is sufficient for both XY gonadal dysgenesis and XY ovotesticular DSD. Furthermore, array-CGH is a very useful tool in the molecular diagnosis of DSD.
Bera, Anindita; Rakshit, Debraj; SenDe, Aditi; Sen, Ujjwal
2017-06-01
We investigate equilibrium statistical properties of the isotropic quantum XY spin-1/2 model in an external magnetic field when the interaction and field parts are subjected to quenched or annealed disorder or both. The randomness present in the system are termed annealed or quenched depending on the relation between two different time scales—the time scale associated with the equilibration of the randomness and the time of observation. Within a mean-field framework, we study the effects of disorders on spontaneous magnetization, both by perturbative and numerical techniques. Our primary interest is to understand the differences between quenched and annealed cases, and also to investigate the interplay when both of them are present in a system. We find that the magnetization survives in the presence of a unidirectional random field, irrespective of its nature, i.e., whether it is quenched or annealed. However, the field breaks the circular symmetry of the magnetization, and the system magnetizes in specific directions, parallel or transverse to the applied magnetic field. Interestingly, while the transverse magnetization is affected by the annealed disordered field, the parallel one remains unfazed by the same. Moreover, the annealed disorder present in the interaction term does not affect the system's spontaneous magnetization and the corresponding critical temperature, irrespective of the presence or absence of quenched or annealed disorder in the field term. We carry out a comparative study of these and all other different combinations of the disorders in the interaction and field terms, and point out their generic features.
Wong, Y S; Tam, Y H; Pang, K K Y; To, K F; Chan, S S C; Chan, K W; Lee, K H
2017-10-01
Gonadal dysgenesis is unique in disorders of sex development (DSD), in that it can be associated with 46,XX, 46,XY or mosaic 45,X/46,XY karyotypes. Gonadal dysgenesis can be partial or complete. Gonadal dysgenesis associated with the Y-chromosome has increased risk of gonadal germ cell neoplasms. Most of the literature focus on 45,X/46,XY gonadal dysgenesis, while there are scanty data on the condition when the karyotype is non-mosaic 46,XY. To investigate the diversity of clinical pictures of children presenting with 46,XY DSD due to gonadal dysgenesis. A retrospective study on consecutive patients diagnosed with 46,XY gonadal dysgenesis at age ≤18 years in a tertiary center from 1985 to 2015. The clinical presentations, phenotypes, gonadal features and associated anomalies were investigated. Twenty-eight patients with Y-chromosome gonadal dysgenesis were identified during the study period and six (21.4%) had non-mosaic 46,XY karyotype. Three had complete gonadal dysgenesis (CGD) with normal female phenotype, while the other three had partial gonadal dysgenesis (PGD). Of the three patients with CGD, two presented with the classical Swyer syndrome at adolescence, while the third presented at birth with multiple congenital anomalies. The three PGD patients presented with ambiguous genitalia at birth (n = 2), and isolated hypospadias (n = 1), which was associated with Frasier syndrome. Three patients had germ cell neoplasms: bilateral gonadoblastoma (n = 1), bilateral intratubular germ cell neoplasia unclassified (n = 1), and dysgerminoma + gonadoblastoma (n = 1). Two patients had global developmental delay with other congenital anomalies, and another patient had learning difficulties with borderline intelligence (Table). The findings suggest that 46,XY gonadal dysgenesis is much rarer than 45,X/46,XY gonadal dysgenesis. Patients differed in their clinical presentations and well-established syndromes happened in half of them. Overall, the risk of germ
A comparison principle for singular parabolic equations in the Heisenberg group
Directory of Open Access Journals (Sweden)
Pablo Ochoa
2015-04-01
Full Text Available In this work, we prove a comparison principle for singular parabolic equations with boundary conditions in the context of the Heisenberg group. In particular, this result applies to interesting equations, such as the parabolic infinite Laplacian, the mean curvature flow equation and more general homogeneous diffusions.
Wouters, B.; De Nardis, J.; Brockmann, M.; Fioretto, D.; Rigol, M.; Caux, J.-S.
2014-01-01
We study quenches in integrable spin-1/2 chains in which we evolve the ground state of the antiferromagnetic Ising model with the anisotropic Heisenberg Hamiltonian. For this nontrivially interacting situation, an application of the first-principles-based quench-action method allows us to give an
Thermodynamic behavior of the XXZ Heisenberg s=1/2 chain around the factorizing magnetic field
Abouie, J.; Langari, A.; Siahatgar, M.
2008-01-01
We have investigated the zero and finite temperature behaviors of the anisotropic antiferromagnetic Heisenberg XXZ spin-1/2 chain in the presence of a transverse magnetic field (h). The attention is concentrated on an interval of magnetic field between the factorizing field (h_f) and the critical one (h_c). The model presents a spin-flop phase for 0
Werner Heisenberg and the German Uranium Project 1939 - 1945. Myths and Facts
Gottstein, Klaus
2016-01-01
The results of a careful analysis of all the available information on the activities of Heisenberg and of his talks during the years 1939 to 1945 can be summarized in the following way. Like several other German physicists Heisenberg was drafted by German Army Ordnance when war began in Europe in September 1939 to investigate whether the energy from splitting Uranium nuclei by neutrons could be used for technical and military purposes. Heisenberg found that this is possible in principle but that military use would require such enormous industrial expenditures that it would take many years and would be impracticable while the war lasted. The project was therefore dropped by the Nazi government in 1942. Heisenberg even refrained from calculating a precise value for the critical mass of U 235. He was relieved that he was thus spared a moral decision between obeying an order to build the bomb or risking his life by refusing to be involved in the project or sabotaging it. He was happy to be confined to a project o...
Half-magnetization plateau in a Heisenberg antiferromagnet on a triangular lattice
Ye, Mengxing; Chubukov, Andrey V.
2017-10-01
We present the phase diagram of a 2D isotropic triangular Heisenberg antiferromagnet in a magnetic field. We consider spin-S model with nearest-neighbor (J1) and next-nearest-neighbor (J2) interactions. We focus on the range of 1 /8 border the "three up, one down" state and discuss the transitions between these states and the canted stripe state.
Neutron Scattering from the Heisenberg Ferromagnets EuO and EuS
DEFF Research Database (Denmark)
Dietrich, O. W.; Als-Nielsen, Jens Aage; Passell, L.
1976-01-01
Inelastic neutron scattering has been used to investigate the spin dynamics of the isotropic Heisenberg ferromagnet EuO over a wide range of wave vectors and over a temperature range extending from 0.14 to 1.9TC. Below the ordering temperature spin-wave renormalization is found to agree well...
Exact Results for Spin-Wave Renormalisation in Heisenberg and Planar Ferromagnets
DEFF Research Database (Denmark)
Rastelli, E.; Lindgård, Per-Anker
1979-01-01
An exact perturbation expansion, to the order 1/S2, is derived for the Heisenberg ferromagnet. The equivalence of the Dyson-Maleev (DM), Holstein-Primakoff (HP) and matching-of-matrix-element (MME) transformations is proven. They give identical T5/2 and T4 coefficients. For the planar ferromagnet...
While Heisenberg Is Not Looking: The Strength of "Weak Measurements" in Educational Research
Geelan, David R.
2015-01-01
The concept of "weak measurements" in quantum physics is a way of "cheating" the Uncertainty Principle. Heisenberg stated (and 85 years of experiments have demonstrated) that it is impossible to know both the position and momentum of a particle with arbitrary precision. More precise measurements of one decrease the precision…
Cryptic genomic rearrangements in three patients with 46,XY disorders of sex development.
Igarashi, Maki; Dung, Vu Chi; Suzuki, Erina; Ida, Shinobu; Nakacho, Mariko; Nakabayashi, Kazuhiko; Mizuno, Kentaro; Hayashi, Yutaro; Kohri, Kenjiro; Kojima, Yoshiyuki; Ogata, Tsutomu; Fukami, Maki
2013-01-01
46,XY disorders of sex development (46,XY DSD) are genetically heterogeneous conditions. Recently, a few submicroscopic genomic rearrangements have been reported as novel genetic causes of 46,XY DSD. To clarify the role of cryptic rearrangements in the development of 46,XY DSD, we performed array-based comparative genomic hybridization analysis for 24 genetic males with genital abnormalities. Heterozygous submicroscopic deletions were identified in three cases (cases 1-3). A ∼8.5 Mb terminal deletion at 9p24.1-24.3 was detected in case 1 that presented with complete female-type external genitalia and mental retardation; a ∼2.0 Mb interstitial deletion at 20p13 was identified in case 2 with ambiguous external genitalia and short stature; and a ∼18.0 Mb interstitial deletion at 2q31.1-32 was found in case 3 with ambiguous external genitalia, mental retardation and multiple anomalies. The genital abnormalities of case 1 could be ascribed to gonadal dysgenesis caused by haploinsufficiency of DMRT1, while those of case 3 were possibly associated with perturbed organogenesis due to a deletion of the HOXD cluster. The deletion in case 2 affected 36 genes, none of which have been previously implicated in sex development. The results indicate that cryptic genomic rearrangements constitute an important part of the molecular bases of 46,XY DSD and that submicroscopic deletions can lead to various types of 46,XY DSD that occur as components of contiguous gene deletion syndromes. Most importantly, our data provide a novel candidate locus for 46,XY DSD at 20p13.
Nakano, Hiroki; Sakai, Tôru
2017-11-01
An S = 1/2 triangular-lattice Heisenberg antiferromagnet with next-nearest-neighbor (NNN) interactions is investigated under a magnetic field by the numerical-diagonalization method. It is known that, in both cases of weak and strong NNN interactions, this system reveals a magnetization plateau at one-third of the saturated magnetization. We examine the stability of this magnetization plateau when the amplitude of NNN interactions is varied. We find that a nonplateau region appears between the plateau phases in the cases of weak and strong NNN interactions.
Zad, Hamid Arian; Movahhedian, Hossein
2017-05-01
In the present work, initially, a mixed-three-spin (1/2,1,1/2) cell of a mixed-N-spin chain with Ising-XY model is introduced, for which pair spins (1,1/2) have Ising-type interaction and pair spins (1/2,1/2) have both XY-type and Dzyaloshinskii-Moriya (DM) interactions together. An external homogeneous magnetic field B is considered for the system in thermal equilibrium. Integer-spins have a single-ion anisotropy property with coefficient ζ. Then, we investigate the quantum entanglement between half-spins (1/2,1/2), by means of the concurrence. Classical correlation (CC) for this pair of spins is investigated as well as the concurrence and some interesting temperature, the magnetic field and the DM interaction properties are expressed. Moreover, single-ion anisotropy effects on the correlation between half-spins is verified. According to the verifications based on the communication channels category by Rossini, Giovannetti and Fazio [D. Rossini, V. Giovannetti and R. Fazio, Int. J. Quantum Inf. 5, 439 (2007)], we theoretically consider such tripartite spin model as an ideal quantum channel, then calculate its information transmission rate and express some differences in behavior between this suggested model and introduced simple models in the previous works (chains without spin integer and DM interaction) from information transferring protocol point of view.
Masculinised Behaviour of XY Females in a Mammal with Naturally Occuring Sex Reversal.
Saunders, Paul A; Franco, Thomas; Sottas, Camille; Maurice, Tangui; Ganem, Guila; Veyrunes, Frédéric
2016-03-11
Most sex differences in phenotype are controlled by gonadal hormones, but recent work on laboratory strain mice that present discordant chromosomal and gonadal sex showed that sex chromosome complement can have a direct influence on the establishment of sex-specific behaviours, independently from gonads. In this study, we analyse the behaviour of a rodent with naturally occurring sex reversal: the African pygmy mouse Mus minutoides, in which all males are XY, while females are of three types: XX, XX* or X*Y (the asterisk represents an unknown X-linked mutation preventing masculinisation of X*Y embryos). X*Y females show typical female anatomy and, interestingly, have greater breeding performances. We investigate the link between sex chromosome complement, behaviour and reproductive success in females by analysing several behavioural features that could potentially influence their fitness: female attractiveness, aggressiveness and anxiety. Despite sex chromosome complement was not found to impact male mate preferences, it does influence some aspects of both aggressiveness and anxiety: X(*)Y females are more aggressive than the XX and XX*, and show lower anxiogenic response to novelty, like males. We discuss how these behavioural differences might impact the breeding performances of females, and how the sex chromosome complement could shape the differences observed.
DNA copy number variations in patients with 46,XY disorders of sex development.
Harrison, Steven M; Granberg, Candace F; Keays, Melise; Hill, Martinez; Grimsby, Gwen M; Baker, Linda A
2014-12-01
Less than 50% of cases of 46,XY disorders of sex development are genetically defined after karyotyping and/or sequencing of known causal genes. Since copy number variations are often missed by karyotyping and sequencing, we assessed patients with unexplained 46,XY disorders of sex development using array comparative genomic hybridization for possible disease causing genomic variants. DNA from unexplained cases of 46,XY disorders of sex development were tested by whole genome array comparative genomic hybridization. In cases where novel copy number variations were detected parental testing was performed to identify whether copy number variations were de novo or inherited. Of the 12 patients who underwent array comparative genomic hybridization testing 2 had possible copy number variations causing disorders of sex development, both maternally inherited microdeletions. One case, with a maternal history of premature ovarian failure, had a cosegregating microdeletion on 9q33.3 involving NR5A1. The other case, with a maternal family history of congenital heart disease, had a cosegregating microdeletion on 8p23.1 upstream of GATA4. In this cohort copy number variations involving or adjacent to known causal genes led to 46,XY disorders of sex development in 2 of 12 previously unexplained cases (17%). Copy number variation testing is clinically indicated for unexplained cases of 46,XY disorders of sex development to aid in genetic counseling for family planning. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
A Rare Cause of Male Infertility: 45,X/46,XY Mosaicism.
Akinsal, Emre Can; Baydilli, Numan; Bayramov, Ruslan; Ekmekcioglu, Oguz
2017-11-21
To present the clinical, chromosomal, and endocrinological features of 8 infertile male cases with the 45,X/46,XY karyotype who were admitted to our infertility clinic. The records of cases who were admitted to our infertility clinic between 1999 and 2015 were investigated. Eight cases with 45,X/46,XY were detected. The clinical, endocrinological, and chromosomal assessments were analyzed. Each patient's height, weight, body mass index, testicular volume, endocrine hormone levels, follow-up period semen analysis, testicular biopsy reports, and karyotype analysis were evaluated retrospectively. Some cases had a short stature, but often their phenotypes were normal. Seven of the cases had normal testosterone levels and all cases, except one, had elevated gonadotropin levels. All cases were azoospermic and testicular biopsy showed Sertoli cell-only syndrome. Peripheral blood karyotype revealed 45,X/46,XY mosaicism in all cases. Metaphase counts and percentages were different. Individuals with 45,X/46,XY mosaicism that have a normal male phenotype form make up a rare subgroup of the 45,X/46,XY karyotype. These individuals usually present with infertility and were diagnosed based on the results of the karyotype analysis during azoo or severe oligospermia evaluation. © 2017 S. Karger AG, Basel.
Zhou, Linyan; Charkraborty, Tapas; Zhou, Qian; Mohapatra, Sipra; Nagahama, Yoshitaka; Zhang, Yueguang
2016-01-19
In contrast to our understanding of testicular differentiation, ovarian differentiation is less well understood in vertebrates. In mammals, R-spondin1 (Rspo1), an activator of Wnt/β-catenin signaling pathway, is located upstream of the female sex determination pathway. However, the functions of Rspo1 in ovarian differentiation remain unclear in non-mammalian species. In order to elucidate the detailed functions of Rspo/Wnt signaling pathway in fish sex determination/differentiation, the ectopic expression of the Rspo1 gene was performed in XY medaka (Oryzias latipes). The results obtained demonstrated that the gain of Rspo1 function induced femininity in XY fish. The overexpression of Rspo1 enhanced Wnt4b and β-catenin transcription, and completely suppressed the expression of male-biased genes (Dmy, Gsdf, Sox9a2 and Dmrt1) as well as testicular differentiation. Gonadal reprograming of Rspo1-over-expressed-XY (Rspo1-OV-XY) fish, induced the production of female-biased genes (Cyp19a1a and Foxl2), estradiol-17β production and further female type secondary sexuality. Moreover, Rspo1-OV-XY females were fertile and produced successive generations. Promoter analyses showed that Rspo1 transcription was directly regulated by DM domain genes (Dmy, the sex-determining gene, and Dmrt1) and remained unresponsive to Foxl2. Taken together, our results strongly suggest that Rspo1 is sufficient to activate ovarian development and plays a decisive role in the ovarian differentiation in medaka.
The XY Body of the Cat (Felis catus): Structural Differentiations and Protein Immunolocalization.
Sciurano, Roberta B; De Luca, Geraldine; Rahn, I Mónica; Solari, Alberto J
2017-01-01
The heteromorphic X and Y chromosomes behave in a special way in mammalian spermatocytes; they form the XY body and synapse only partially. The aim of this article was to study the origin and the role of the special differentiations in the XY pair of the domestic cat during pachytene by analyzing its fine structural characteristics and the immunolocalization of the main meiotic proteins SYCP3, SYCP1, SYCE3, SMC3, γ-H2AX, BRCA1, H3K27me3, and MLH1. The cat XY body shows particularly striking structures: an extreme degree of axial fibrillation in late pachynema and a special location of SYCP3-containing fibrils, bridging different regions of the main X axis, as well as one bridge at the inner end of the pairing region that colocalizes with the single mandatory MLH1 focus. There are sequential changes, first bullous expansions, then subdivision into fibrils, all involving axial thickening. The chromatin of the XY body presents the usual features of meiotic sex chromosome inactivation. An analysis of the XY body of many eutherians and metatherians suggests that axial thickenings are primitive features. The sequential changes in the mass and location of SYCP3-containing fibers vary among the clades because of specific processes of axial assembly/disassembly occurring in different species. © 2017 S. Karger AG, Basel.
Thermal Order-by-Disorder at Criticality in XY Pyrochlore Magnets
Gingras, Michel; Javanparast, Behnam; Day, Alexandre; Hao, Zhihao
2014-03-01
We investigate analytically and numerically the problem of long-range order selection via thermal fluctuations close to the critical region of the paramagnetic phase to long-range order transition in a system of interacting XY spins on the pyrochlore lattice and for which we consider the most general bilinear anisotropic nearest-neighbor spin Hamiltonian. At the standard mean-field theory (s-MFT) level, in a certain region of the parameter space of this Hamiltonian, the ordered state displays an accidental U(1) degeneracy. This degeneracy is lifted by fluctuations beyond s-MFT and a certain form of order-by-disorder near criticality is thus fund to be at play. We analytically explore this selection at the microscopic level by using an extension of the method originally developed by Thouless, Anderson and Palmer (TAP) to study the effect of fluctuations in spin glasses. These TAP calculations provide an insight into the long-range order fluctuation-induced selection mechanism in terms of the spin-spin coupling constants of the microscopic Hamiltonian. We also employ a cluster mean field theory (c-MFT) to further explore numerically this problem.
Ret Finger Protein: An E3 Ubiquitin Ligase Juxtaposed to the XY Body in Meiosis
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Isabelle Gillot
2009-01-01
Full Text Available During prophase I of male meiosis, the sex chromosomes form a compact structure called XY body that associates with the nuclear membrane of pachytene spermatocytes. Ret Finger Protein is a transcriptional repressor, able to interact with both nuclear matrix-associated proteins and double-stranded DNA. We report the precise and unique localization of Ret Finger Protein in pachytene spermatocytes, in which Ret Finger Protein takes place of lamin B1, between the XY body and the inner nuclear membrane. This localization of Ret Finger Protein does not seem to be associated with O-glycosylation or sumoylation. In addition, we demonstrate that Ret Finger Protein contains an E3 ubiquitin ligase activity. These observations lead to an attractive hypothesis in which Ret Finger Protein would be involved in the positioning and the attachment of XY body to the nuclear lamina of pachytene spermatocytes.
seXY: a tool for sex inference from genotype arrays.
Qian, David C; Busam, Jonathan A; Xiao, Xiangjun; O'Mara, Tracy A; Eeles, Rosalind A; Schumacher, Frederick R; Phelan, Catherine M; Amos, Christopher I
2017-02-15
Checking concordance between reported sex and genotype-inferred sex is a crucial quality control measure in genome-wide association studies (GWAS). However, limited insights exist regarding the true accuracy of software that infer sex from genotype array data. We present seXY, a logistic regression model trained on both X chromosome heterozygosity and Y chromosome missingness, that consistently demonstrated >99.5% sex inference accuracy in cross-validation for 889 males and 5,361 females enrolled in prostate cancer and ovarian cancer GWAS. Compared to PLINK, one of the most popular tools for sex inference in GWAS that assesses only X chromosome heterozygosity, seXY achieved marginally better male classification and 3% more accurate female classification. https://github.com/Christopher-Amos-Lab/seXY. Christopher.I.Amos@dartmouth.edu. Supplementary data are available at Bioinformatics online.
Dierks, Claudia; Sieme, Harald; Piechotta, Marion; Lehner, Stephanie; Merkt, Jan Carlos; Uphaus, Hubert; Klug, Erich; Distl, Ottmar
2015-01-01
A female thoroughbred successful in horse racing was positively tested for high testosterone values. This horse neither showed stallion-like-behaviour nor signs of ambiguous external genitalia. The karyotype of this horse was 2n = 64,XY and the sex-determining region of Y (SRY) PCR was positive. Hair samples tested for naturally testosterone revealed values normal for stallions, and tests for eight synthetic testosterone esters remained negative. The phenotype, ultrasonographic examination, hormone status, cytogenetic evaluation and molecular diagnostics lead to the diagnosis of an XY testicular disorder of sexual development (DSD) due to a complete androgen insensitivity syndrome. To our knowledge this is the first report about a thoroughbred in racing sports with an XY testicular disorder of sexual development. To date, intersex racing horses have never been described in thoroughbreds or a regulation for intersexes in regard to horse races has been issued.
Shi, Jing; Jin, Yongxin; Bian, Ting; Li, Kewei; Sun, Ziyu; Cheng, Zhihui; Jin, Shouguang; Wu, Weihui
2015-10-01
Translation elongation is modulated by various ribosome-binding proteins. Environmental stresses, such as starvation and antibiotics, can cause stalling of bacterial ribosomes, which may alter gene expression through a transcription or translation attenuation mechanism. In Pseudomonas aeruginosa, the expression of MexXY multidrug efflux system, which plays a significant role in resistance against aminoglycoside antibiotics, is controlled by a translation surveillance mechanism. Stalling of ribosome at the PA5471 leader peptide (PA5471.1) mRNA leads to transcription of PA5471, which subsequently up-regulates the expression of MexXY. In this study, we found that mutation in a suhB gene leads to decreased susceptibility to aminoglycosides. Transcriptomic analysis revealed an up-regulation of MexXY and PA5471, which were demonstrated to be responsible for the decreased susceptibility of the suhB mutant. We further demonstrated that PA5471.1 is essential for the up-regulation of PA5471 in the suhB mutant. Co-immunoprecipitation assay revealed an interaction between SuhB and ribosome, suggesting a role of SuhB in translation. Indeed, higher amount of PA5471.1 mRNA was found to associate with ribosome isolated from the suhB mutant, indicating increased ribosome stalling. Therefore, this study identified SuhB as a novel ribosome associated protein that is involved in modulating ribosome activity. © 2015 John Wiley & Sons Ltd.
Fmt bypass in Pseudomonas aeruginosa causes induction of MexXY efflux pump expression.
Caughlan, Ruth E; Sriram, Shubha; Daigle, Denis M; Woods, Angela L; Buco, Jennifer; Peterson, Ron L; Dzink-Fox, Joann; Walker, Susan; Dean, Charles R
2009-12-01
The intrinsic resistance of P. aeruginosa PAO1 to the peptide deformylase inhibitor (PDF-I) LBM415 was mediated by the MexAB-OprM and MexXY-OprM efflux pumps, the latter of which was strongly induced by LBM415. Single-step exposure of PAO1 deleted for mexAB-oprM (therefore lacking both MexAB-OprM and MexXY-OprM functions) to PDF-Is selected for nfxB mutants, which express the MexCD-OprJ efflux pump, indicating that these compounds are also substrates for this pump. Selection of resistant mutants by use of levels of LBM415 greater than that accommodated by efflux yielded two additional groups of mutations, in the methionyl-tRNA(fmet) formyltransferase (fmt) and folD genes. Both mechanisms are known to impose an in vitro growth deficit (also observed here), presumably due to impairment of protein synthesis. We surmised that this inherent impairment of protein synthesis would upregulate expression of mexXY in a fashion similar to upregulation by LBM415 or by ribosome inhibitory compounds. Transcriptional profiling and/or mexX::lux promoter fusion analysis revealed that fmt and folD mutants were strongly upregulated for mexXY and another gene known to be required for upregulation of the pump, PA5471. Complementation of the fmt mutation in trans reversed this constitutive expression. This supports the notion that MexXY has a natural physiological function responding to impairment of ribosome function or protein synthesis and that fmt mutation (Fmt bypass) and folD mutation generate the intracellular mexXY-inducing signal.
Gottlob, A P
1994-01-01
We present the results of a Monte Carlo study of the three-dimensional XY model and the three-dimensional antiferromagnetic three-state Potts model. In both cases we compute the difference in the free energies of a system with periodic and a system with antiperiodic boundary conditions in the neighbourhood of the critical coupling. From the finite-size scaling behaviour of this quantity we extract values for the critical temperature and the critical exponent nu that are compatible with recent high statistics Monte Carlo studies of the models. The results for the free energy difference at the critical temperature and for the exponent nu confirm that both models belong to the same universality class.
Dysgerminoma in a case of 46, XY pure gonadal dysgenesis (swyer syndrome: a case report
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He Anguang
2011-09-01
Full Text Available Abstract Simple 46, XY gonadal dysgenesis syndrome, also called Swyer syndrome, is known as pure gonadal dysgenesis. Individuals with the syndrome are characterized by 46, XY karyotype and phenotypically female with female genital appearance, normal Müllerian structures and absent testicular tissue. The condition usually first becomes apparent in adolescence with delayed puberty and primary amenorrhea due to the gonads have no hormonal or reproductive potential. Herein, we report a case of dysgerminoma diagnosed in a dysgenetic gonad of a 21-year-old patient with Swyer syndrome.
A Cytogenomic Approach in a Case of Syndromic XY Gonadal Dysgenesis.
Simioni, Milena; Lopes Monlleó, Isabella; Costa de Queiroz, Camila M; Fragoso Peixoto Gazzaneo, Ilanna; Lima do Nascimento, Diogo L; Luna de Omena Filho, Reinaldo; Santos da Cruz Piveta, Cristiane; Palandi de Mello, Maricilda; Gil-da-Silva-Lopes, Vera L
2016-01-01
This is the first molecular characterization of a female XY patient with an Xp duplication due to an X;22 translocation. Array CGH detected a copy number gain of ∼36 Mb in the Xp22.33p21.1 region involving 150 genes. Clinical and molecular studies described in the literature have suggested DAX1 duplication as the major cause responsible for a sex reversal phenotype. Additionally, the interaction between genes and their possible role in clinical features are presented to support the discussion on genotype-phenotype correlation in cases of syndromic XY gonadal dysgenesis. © 2016 S. Karger AG, Basel.
47, XY, +der(Y),t(X;Y)(p21.1;p11.2): a unique case of XY sex reversal.
Zarate, Yuri A; Dwivedi, Alka; Bartel, Frank O; Corning, Ken; Dupont, Barbara R
2011-02-01
Translocations involving the short arms of the X and Y chromosomes are rare and can result in a functional disomy of the short arm of the X chromosome, including the dosage-sensitive sex reversal (DSS) locus. A result of such imbalance may be sex reversal with multiple congenital anomalies. We present the clinical and cytogenetic evaluation of a newborn infant with DSS and additional clinical findings of minor facial anomalies, left abdominal mass, 5th finger clinodactyly, and mild hypotonia. The external genitalia appeared to be normal female. The infant had bilateral corneal opacities and findings suggestive of anterior segment dysgenesis. Ultrasonography showed a small uterus with undetectable ovaries, and a left multicystic dysplastic kidney. High-resolution chromosome analysis identified the presence of a derivative Y chromosome, 47,XY, +der(Y)t(X;Y)(p21.1;p11.2), which was confirmed by fluorescence in situ hybridization studies. Array CGH showed a 35.1 Mb copy number gain of chromosome region Xp22.33-p21.1 and a 52.2 Mb copy number gain of Yp11.2-qter, in addition to the intact X and Y chromosomes. Previously reported patients with XY sex reversal have not had DSS with corneal opacities, dysgenesis of the anterior segment of the eye, and unilateral multicystic dysplastic kidney. These findings represent a new form of XY sex reversal due to an Xp duplication. Copyright © 2010 Wiley-Liss, Inc.
Energy Technology Data Exchange (ETDEWEB)
Maeter, H.; Klauss, H.H. [Institut fuer Festkoerperphysik, TU Dresden (Germany); Zvyagin, A.A. [Institut fuer Festkoerperphysik, TU Dresden (Germany); Institute for Low Temperature Physics and Engineering, NAS of Ukraine, Kharkov (Ukraine); Luetkens, H.; Pascua, G.; Shermadini, Z. [Laboratory for Muon-Spin Spectroscopy, Paul Scherrer Institute, Villigen (Switzerland); Hess, C.; Hlubek, N.; Buechner, B. [Leibniz-Institut fuer Festkoerper- und Werkstoffforschung, Dresden (Germany); Saint-Matin, R.; Revcolevschi, A. [Laboratoire de Physico-Chimie de L' Etat Solide, ICMMO, UMR 8182, Universite Paris-Sud, Orsay (France)
2011-07-01
For one-dimensional quantum spin chain systems recent experimental and theoretical studies indicate unexpectedly large, in some cases diverging spin and heat transport coefficients. Local probes, like e.g. muon spin relaxation ({mu}SR) can indirectly characterize the spin transport properties of low dimensional systems via the magnetic field dependence of the spin lattice relaxation rate {lambda}(B). For diffusive spin transport {lambda}{proportional_to}B{sup -0.5} is expected. For the ground state of the isotropic spin-1/2 antiferromagnetic Heisenberg chain the eigenstates of the Heisenberg Hamiltonian dominate the spin transport, which is then ballistic. Using the Mueller ansatz {lambda}{proportional_to}B{sup -1} is expected in this case. For SrCuO{sub 2} we find {lambda}{proportional_to}B{sup -0.9(3)}. This result is temperature independent for 5 K{<=}T {<=}300 K. Within conformal field theory and using the Mueller ansatz we conclude ballistic spin transport in SrCuO{sub 2}.
Chimerism 47,XY,+21/46,XX in a female infant with anencephaly and other congenital defects
Directory of Open Access Journals (Sweden)
Danielle R. Lucon
2006-01-01
Full Text Available Chimerism is rare in humans and is usually discovered accidentally when a 46,XX and 46,XY karyotype is found in a same individual. We describe a malformed female infant with neural tube defect (NTD and a 47,XY,+21[5]/46,XX[30] karyotype.
Numerical linked-cluster expansion for the distorted kagome lattice Heisenberg model
Khatami, Ehsan; Rigol, Marcos
2012-12-01
Motivated by experimental results for the thermodynamic properties of the Rb2Cu3SnF12 material and the discovery of its valence-bond solid ground state, we utilize the numerical linked-cluster expansions (NLCEs) and devise an expansion tailored to solve the Heisenberg model on a pinwheel-distorted kagome lattice. Using the exchange interactions that are relevant to Rb2Cu3SnF12, we calculate its uniform spin susceptibility and find a very good agreement with experiment. Next, we focus on the ground state of a simplified model of the distorted kagome lattice and take advantage of a zero-temperature Lanczos-based NLCE to study the approach to the ground state of the uniform kagome lattice Heisenberg model using a tuning parameter. Together with results from exact diagonalization of finite clusters, we find evidence that a phase transition occurs before the uniform limit is reached.
Rojas, Onofre; Strečka, Jozef; Lyra, Marcelo L.
2013-05-01
The spin-1/2 Ising-Heisenberg tetrahedral chain is exactly solved using its local gauge symmetry (the total spin of the Heisenberg bonds is locally conserved) and the transfer-matrix approach. Exact results derived for spin-spin correlation functions are employed to obtain the frustration temperature. In addition, we have exactly calculated a concurrence quantifying thermal entanglement. It is shown that the frustration and threshold temperature coincide at sufficiently low temperatures, while they exhibit a very different behavior in the high-temperature region when tending towards completely different asymptotic limits. The threshold temperature additionally shows a notable reentrant behavior when it extends over a narrow temperature region above the classical ground state without any quantum correlations.
Heisenberg 1901-1976 : le témoignage de sa femme
Heisenberg, Elisabeth
1990-01-01
Une femme raconte la vie de son mari, Werner Heisenberg, Prix Nobel de Physique 1932. Après une enfance heureuse, ce brillant étudiant fut l'élève d'Albert Einstein, Niels Bohr, Arnold Sommerfeld. Mais à l'époque de la montée du nazisme, le grand physicien refusa de quitter son pays, cautionnant ainsi le régime d'Hitler et participant à "l'effort de guerre", c'est-à-dire à la course à la bombe. Le témoignage d'Elisabeth Heisenberg bien que naturellement subjectif, permet de saisir les ressorts psychologiques du comportement d'un savant face aux terrifiantes réalités de son époque.
Un'estrema solitudine la vita e l'opera di Werner Heisenberg
Cassidy, David C
1996-01-01
Il genio di Werner Heisenberg attraversa l'orizzonte della fisica del nostro secolo come una meteora. Testimoniano della fecondità e dell'originalità del suo pensiero non solo il Nobel che gli fu assegnato a soli 32 anni, ma soprattutto i decisivi impulsi da lui dati alla fisica quantistica, alla teoria delle particelle elementari, alla teoria del nucleo. Si deve a Heisenberg quel "principio di indeterminazione" che ha rivoluzionato non solo il corso della fisica ma il modo di concepire la posizione dell'uomo nell'universo. L'interesse del libro, però, vuole andare oltre la fisica, giacché il curriculum del "ragazzo di campagna dei biondi capelli" rispecchia in forma emblematica l'ambiguo rapporto della scienza col potere.
A continuous analysis for the antiferromagnetic Heisenberg model on the checkerboard lattice
Moura, A. R.; Pereira, A. R.
2017-11-01
In this paper we investigate the antiferromagnetic Heisenberg model on the checkerboard lattice by the O (3) Non-linear Sigma Model (NLSM). The checkerboard lattice is distinguished from the antiferromagnetic square lattice (with coupling constant J) by the presence of diagonal crossing (with coupling constant J‧) in half of the sites. This lattice model is the direct analogous of the three-dimensional pyrochlore lattice in a two-dimensional surface. Many effects of the three-dimensional model version, as the Quantum Order-by-Disorder, have been recently described also in the checkerboard lattice. Here we have developed the continuous version of the Heisenberg model on the checkerboard lattice and applied Renormalization Group together other techniques to analyze the both cases J J‧. We have therefore determined the effects of the crossing interaction J‧ on the phase transitions. In addition, skyrmion solutions and their possible influences on these transitions were also considered.
A representation of Weyl-Heisenberg Lie algebra in the quaternionic setting
Muraleetharan, B.; Thirulogasanthar, K.; Sabadini, I.
2017-10-01
Using a left multiplication defined on a right quaternionic Hilbert space, linear self-adjoint momentum operators on a right quaternionic Hilbert space are defined in complete analogy with their complex counterpart. With the aid of the so-obtained position and momentum operators, we study the Heisenberg uncertainty principle on the whole set of quaternions and on a quaternionic slice, namely on a copy of the complex plane inside the quaternions. For the quaternionic harmonic oscillator, the uncertainty relation is shown to saturate on a neighborhood of the origin in the case we consider the whole set of quaternions, while it is saturated on the whole slice in the case we take the slice-wise approach. In analogy with the complex Weyl-Heisenberg Lie algebra, Lie algebraic structures are developed for the quaternionic case. Finally, we introduce a quaternionic displacement operator which is square integrable, irreducible and unitary, and we study its properties.
Roura, Albert
2017-04-21
Atom interferometry tests of universality of free fall based on the differential measurement of two different atomic species provide a useful complement to those based on macroscopic masses. However, when striving for the highest possible sensitivities, gravity gradients pose a serious challenge. Indeed, the relative initial position and velocity for the two species need to be controlled with extremely high accuracy, which can be rather demanding in practice and whose verification may require rather long integration times. Furthermore, in highly sensitive configurations gravity gradients lead to a drastic loss of contrast. These difficulties can be mitigated by employing wave packets with narrower position and momentum widths, but this is ultimately limited by Heisenberg's uncertainty principle. We present a promising scheme that overcomes these problems by compensating the effects of the gravity gradients and circumvents the fundamental limitations due to Heisenberg's uncertainty principle. Furthermore, it relaxes the experimental requirements on initial colocation by several orders of magnitude.
Near-Heisenberg-limited parameter estimation precision by a dipolar-Bose-gas reservoir engineering
Tan, Qing-Shou; Yuan, Ji-Bing; Jin, Guang-Ri; Kuang, Le-Man
2017-12-01
We propose a scheme to obtain the Heisenberg-limited parameter estimation precision by immersing atoms in a thermally equilibrated quasi-one-dimensional dipolar Bose-Einstein condensate reservoir. We show that the collisions between the dipolar atoms and the immersed atoms can result in a controllable nonlinear interaction through tuning the relative strength and the sign of the dipolar and contact interaction. We find that the repulsive dipolar interaction reservoir is preferential for the spin squeezing and the appearance of an entangled non-Gaussian state. As a useful resource for quantum metrology, we also show that the non-Gaussian state results in the phase estimation precision in the Heisenberg scaling, outperforming that of the spin-squeezed state.
Zad, Hamid Arian; Movahhedian, Hossein
2016-08-01
Heat capacity of a mixed-three-spin (1/2,1,1/2) antiferromagnetic XXX Heisenberg chain is precisely investigated by use of the partition function of the system for which, spins (1,1/2) have coupling constant J1 and spins (1/2,1/2) have coupling constant J2. We verify tripartite entanglement for the model by means of the convex roof extended negativity (CREN) and concurrence as functions of temperature T, homogeneous magnetic field B and the coupling constants J1 and J2. As shown in our previous work, [H. A. Zad, Chin. Phys. B 25 (2016) 030303.] the temperature, the magnetic field and the coupling constants dependences of the heat capacity for such spin system have different behaviors for the entangled and separable states, hence, we did some useful comparisons between this quantity and negativities of its organized bipartite (sub)systems at entangled and separable states. Here, we compare the heat capacity of the mixed-three-spin (1/2,1,1/2) system with the CREN and the tripartite concurrence (as measures of the tripartite entanglement) at low temperature. Ground state phase transitions, and also, transition from ground state to some excited states are explained in detail for this system at zero temperature. Finally, we investigate the heat capacity behavior around those critical points in which these quantum phase transitions occur.
A convolution type characterization for Lp - multipliers for the Heisenberg group
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R. Radha
2007-01-01
Full Text Available It is well known that if m is an Lp - multiplier for the Fourier transform on ℝn(1
Heisenberg group Hn. Though this result is already known in generality for amenable groups, a simple proof is provided in this paper.
Quantum teleportation in a three-qubit Heisenberg chain with Dzyaloshinsky-Moriya interaction
Xi, Yu-Xing; Huang, Yan-Xia
2015-07-01
The quantum teleportation via thermally entangled states of three-qubit Heisenberg spin chains with Dzyaloshinsky-Moriya (DM) interactions under a homogeneous magnetic field has been investigated. It is found that average fidelity and critical temperature depend on not only temperature, magnetic field, but also coupling coefficients, and DM interactions. What is more, we also find that average fidelity has little to do with entanglement.
Paulinelli, H. G.; SOUZA, S.M. de; Rojas, Onofre
2013-01-01
In this paper we explore the entanglement in orthogonal dimer-plaquette Ising-Heisenberg chain, assembled between plaquette edges, also known as orthogonal dimer plaquettes. The quantum entanglement properties involving an infinite chain structure are quite important, not only because the mathematical calculation is cumbersome but also because real materials are well represented by infinite chain. Using the local gauge symmetry of this model, we are able to map onto a simple spin-1 like Ising...
Sinitsyn, E. V.; Bostrem, I. G.; Ovchinnikov, A. S.
2004-01-01
For two-dimensional Heisenberg antiferromagnet we present an analysis of topological coreless excitations having a stripe form. These textures are characterized by singularities at boundaries. A detailed classification of the stripe textures results in a certain analogy with the coreless excitations in $^3He-A$ phase: Mermin-Ho and Anderson-Toulouse coreless vortices. The excitations of the last type may have a low bulk energy. The stripe textures may be observed as an occurrence of short-ran...
Erlangen Programme at Large 3.1: Hypercomplex Representations of the Heisenberg Group and Mechanics
Kisil, Vladimir V.
2010-01-01
In the spirit of geometric quantisation we consider representations of the Heisenberg(--Weyl) group induced by hypercomplex characters of its centre. This allows to gather under the same framework, called p-mechanics, the three principal cases: quantum mechanics (elliptic character), hyperbolic mechanics and classical mechanics (parabolic character). In each case we recover the corresponding dynamic equation as well as rules for addition of probabilities. Notably, we are able to obtain whole ...
Solving the {eta}-Problem in hybrid inflation with Heisenberg symmetry and stabilized modulus
Energy Technology Data Exchange (ETDEWEB)
Antusch, Stefan; Dutta, Koushik; Kostka, Philipp [Max-Planck-Institut fuer Physik, Werner-Heisenberg-Institut, Muenchen (Germany); Bastero-Gil, Mar [Departamento de Fisica Teorica y del Cosmos and Centro Andaluz de Fisica de Particulas Elementales, Universidad de Granada (Spain); King, Steve [School of Physics and Astronomy, University of Southampton (United Kingdom)
2009-07-01
We present a new class of models in which the {eta}-problem of supersymmetric hybrid inflation is resolved using a Heisenberg symmetry, where the associated modulus field is stabilized and made heavy with the help of the large vacuum energy during inflation without any fine-tuning. A natural candidate for the inflaton in this class of models is the right-handed sneutrino which is massless during the inflationary epoch, and subsequently acquires a large mass at the end of inflation.
Centering conditions for planar septic systems
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Evgenii P. Volokitin
2003-04-01
Full Text Available We find centering conditions for the following $O$-symmetric system of degree 7: $$displaylines{ dot x=y+ x (H_2 (x,y+H_6 (x,y,cr dot y=-x+ y (H_2 (x,y+H_6 (x,y, }$$ where $H_2 (x,y$ and $H_6 (x,y$ are homogeneous polynomials of degrees 2 and 6, respectively. In some cases, we can find commuting systems and first integrals for the original system. We also study the geometry of the central region.
Energy Technology Data Exchange (ETDEWEB)
Rojas, Onofre, E-mail: ors@dex.ufla.br [Departamento de Ciencias Exatas, Universidade Federal de Lavras, 37200-000, Lavras-MG (Brazil); Strečka, Jozef [Department of Theoretical Physics and Astrophysics, Faculty of Science, P.J. Šafárik University, Park Angelinum 9, 040 01 Košice (Slovakia); Lyra, Marcelo L. [Instituto de Física, Universidade Federal de Alagoas, 57072-970, Maceio-AL (Brazil)
2013-05-03
The spin-1/2 Ising–Heisenberg tetrahedral chain is exactly solved using its local gauge symmetry (the total spin of the Heisenberg bonds is locally conserved) and the transfer-matrix approach. Exact results derived for spin–spin correlation functions are employed to obtain the frustration temperature. In addition, we have exactly calculated a concurrence quantifying thermal entanglement. It is shown that the frustration and threshold temperature coincide at sufficiently low temperatures, while they exhibit a very different behavior in the high-temperature region when tending towards completely different asymptotic limits. The threshold temperature additionally shows a notable reentrant behavior when it extends over a narrow temperature region above the classical ground state without any quantum correlations. -- Highlights: ► Using local gauge symmetry we solved the spin-1/2 Ising–Heisenberg tetrahedral chain. ► The frustration temperature was calculated using the correlation functions. ► Thermal entanglement, concurrence and threshold temperature were analyzed. ► The zero-field specific heat was exactly calculated and discussed.
Umemura, Yuria; Miyamoto, Ryosuke; Hashimoto, Rie; Kinoshita, Kyoko; Omotehara, Takuya; Nagahara, Daichi; Hirano, Tetsushi; Kubota, Naoto; Minami, Kiichi; Yanai, Shogo; Masuda, Natsumi; Yuasa, Hideto; Mantani, Youhei; Matsuo, Eiko; Yokoyama, Toshifumi; Kitagawa, Hiroshi; Hoshi, Nobuhiko
2016-01-01
Mammalian sexual fate is determined by the presence or absence of sex determining region of the Y chromosome (Sry) in the "bipotential" gonads. Recent studies have demonstrated that both male and female sexual development are induced by distinct and active genetic pathways. Breeding the Y chromosome from Mus m. domesticus poschiavinus (POS) strains into C57BL/6J (B6J) mice (B6J-XY(POS)) has been shown to induce sex reversal (75%: bilateral ovary, 25%: true hermaphrodites). However, our B6N-XY(POS) mice, which were generated by backcrossing of B6J-XY(POS) on an inbred B6N-XX, develop as males (36%: bilateral testis with fertility as well as bilateral ovary (34%), and the remainder develop as true hermaphrodites. Here, we investigated in detail the expressions of essential sex-related genes and histological features in B6N-XY(POS) mice from the fetal period to adulthood. The onsets of both Sry and SRY-box 9 (Sox9) expressions as determined spatiotemporally by whole-mount immunohistochemistry in the B6N-XY(POS) gonads occurred 2-3 tail somites later than those in B6N-XY(B6) gonads, but earlier than those in B6J-XY(POS), respectively. It is possible that such a small difference in timing of the Sry expression underlies testicular development in our B6N-XY(POS). Our study is the first to histologically show the expression and ectopic localization of a female-related gene in the XY(POS) testes and a male-related gene in the XY(POS) ovaries. The results from these and previous experiments indicate that the interplay between genome variants, epigenetics and developmental gene regulation is crucial for testis development.
A High Rigidity and Precision Scanning Tunneling Microscope with Decoupled XY and Z Scans
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Xu Chen
2017-01-01
Full Text Available A new scan-head structure for the scanning tunneling microscope (STM is proposed, featuring high scan precision and rigidity. The core structure consists of a piezoelectric tube scanner of quadrant type (for XY scans coaxially housed in a piezoelectric tube with single inner and outer electrodes (for Z scan. They are fixed at one end (called common end. A hollow tantalum shaft is coaxially housed in the XY-scan tube and they are mutually fixed at both ends. When the XY scanner scans, its free end will bring the shaft to scan and the tip which is coaxially inserted in the shaft at the common end will scan a smaller area if the tip protrudes short enough from the common end. The decoupled XY and Z scans are desired for less image distortion and the mechanically reduced scan range has the superiority of reducing the impact of the background electronic noise on the scanner and enhancing the tip positioning precision. High quality atomic resolution images are also shown.
Out of equilibrium correlation functions of quantum anisotropic XY models: one-particle excitations
Energy Technology Data Exchange (ETDEWEB)
Amico, Luigi; Osterloh, Andreas [NEST-INFM and Dipartimento di Metodologie Fisiche e Chimiche (DMFCI), Viale A Doria 6, 95125 Catania (Italy)
2004-01-16
We calculate exactly matrix elements between non-equilibrium excitations of the quantum XY model for general anisotropy. These matrix elements are expressed as a sum of Pfaffians. For single particle excitations on the ground state, the Pfaffians in the sum simplify to determinants.
True hermaphroditism in a horned goat with 60XX/60XY chimerism.
Batista, M.; González, F.; Cabrera, F; Palomino, E; Castellano, E.; Calero, P.; Gracia, A.
2000-01-01
Anatomical, behavioral, histological, endocrinological, and cytogenetic characteristics were determined in a horned intersex goat. Histology of the gonads confirmed that the goat was a true hermaphrodite. Cytogenetic analysis showed that it was a chimera (60XX/60XY). Use of laparoscopy allowed determination of characteristics of the internal gonads.
Novel Heterozygous Genetic Variants in Patients with 46,XY Gonadal Dysgenesis.
Chauhan, Vasundhera; Jyotsna, Viveka P; Jain, Vandana; Khadgawat, Rajesh; Dada, Rima
2017-01-01
46,XY gonadal dysgenesis (GD) constitutes a rare group of disorders characterized by the presence of dysfunctional testes in genotypic males. The molecular etiology is not known in about 2 thirds of instances. The aim of this study was to identify the genetic cause in patients with 46,XY gonadal dysgenesis. Based on clinical, cytogenetic, and biochemical screening, 10 patients with 46,XY GD were recruited. Direct sequencing of SRY, NR5A1, SOX9, DAX1, DHH, DMRT1 genes was carried out for molecular analysis. Among 10 patients, 5 were diagnosed with complete gonadal dysgenesis (CGD), 3 with partial gonadal dysgenesis (PGD), and 3 with testicular agenesis. Molecular analysis revealed 12 heterozygous genetic changes, 4 of which were novel. One (c.416T>A) was observed in evolutionary conserved region of DMRT1 gene in a patient with CGD and was found to be probably damaging on in silico analysis. Other 3 were identified in NR5A1 gene (c.990+22 C>A, c.1387+1403T>A and p.131P), but their association with gonadal dysgenesis is not evident from our study. These genetic changes were absent in parents and 50 healthy control samples, which were also studied. With targeted sequencing approach, a molecular diagnosis was made in only one patient with 46,XY GD. The application of new genomic technologies is required for the precise evaluation of these rare genetic defects. © Georg Thieme Verlag KG Stuttgart · New York.
An SU(2) symmetry of the one-dimensional spin-1 XY model
Kitazawa, A; Nomura, K
2003-01-01
We show that the one-dimensional spin-1 XY model has an additional SU(2) symmetry for the open boundary condition and for an artificial one. We can explain some degeneracies of excitation states which were reported in previous numerical studies. (letter to the editor)
The Clinical Manifestation and Genetic Evaluation in Patients with 45,X/46,XY Mosaicism.
Wu, Qinghua; Wang, Cong; Shi, Huirong; Kong, Xiangdong; Ren, Shumin; Jiang, Miao
2017-01-01
45,X/46,XY mosaicism is a rare chromosomal abnormality and probably underdiagnosed. Although clinical and genetic analyses have been performed in some disorders of sexual development, there have been few studies focusing on the phenotype and genetic details of 45,X/46,XY mosaicism, especially in the Chinese population. The aim of this study was to describe the experience of our service in relation to 16 cases with 45,X/46,XY mosaicism. The age at the first evaluation of the patients ranged from 43 days to 30 years. Eight patients were reared as female and 8 as male. The main reasons for examination were primary amenorrhea, sterility, or ambiguous genitalia. Short stature was more common in female than in male patients. Two patients accepted gonadectomy due to tumor risk and none presented gonadal malignancy. The SRY gene was amplified positively in all of the patients. AZF gene microdeletions were present in 6 of 8 male patients, and all adult male patients had no sperm. No correlation has been found between clinical manifestations and the proportion of mosaic cells in peripheral blood. Our observations may permit a better management of people with 45,X/46,XY mosaicism. © 2017 S. Karger AG, Basel.
XY Encounter: A Mathematical Adventure. A Teacher's Guide to Student Discovery through Inquiry.
2000
This print guide to the "XY Encounter" video offers an exciting four-part adventure about two teenage sleuths who discover the presence of an alien below New York City, and expands upon themes presented in the video. As the students try to make contact with the alien, they are confronted with a series of mathematical challenges that test their…
A High Rigidity and Precision Scanning Tunneling Microscope with Decoupled XY and Z Scans.
Chen, Xu; Guo, Tengfei; Hou, Yubin; Zhang, Jing; Meng, Wenjie; Lu, Qingyou
2017-01-01
A new scan-head structure for the scanning tunneling microscope (STM) is proposed, featuring high scan precision and rigidity. The core structure consists of a piezoelectric tube scanner of quadrant type (for XY scans) coaxially housed in a piezoelectric tube with single inner and outer electrodes (for Z scan). They are fixed at one end (called common end). A hollow tantalum shaft is coaxially housed in the XY-scan tube and they are mutually fixed at both ends. When the XY scanner scans, its free end will bring the shaft to scan and the tip which is coaxially inserted in the shaft at the common end will scan a smaller area if the tip protrudes short enough from the common end. The decoupled XY and Z scans are desired for less image distortion and the mechanically reduced scan range has the superiority of reducing the impact of the background electronic noise on the scanner and enhancing the tip positioning precision. High quality atomic resolution images are also shown.
The Berezinskii-Kosterlitz-Thouless transition and correlations in the XY kagome antiferromagnet
Cherepanov, V B; Podivilov, E V
2001-01-01
The problem of the Berezinskii-Kosterlitz-Thouless transition in the highly frustrated XY antiferromagnetic is solved. The transition temperature is found. It is shown that the spin correlation function exponentially decays with distance even in the low-temperature phase, in contrast to the order parameter correlation function, which decays algebraically with distance
Schweizer, Katinka; Brunner, Franziska; Schutzmann, Karsten; Schonbucher, Verena; Richter-Appelt, Hertha
2009-01-01
Individuals living with an intersex condition have not received much attention in counseling psychology, although a high need for psychosocial care is obvious. Using a mixed-methods multiple case study with qualitative and quantitative data, the authors explore coping and gender experiences in seven 46, XY intersexual persons with deficiencies of…
Zhang, Guang-Ming
Applying a symmetric bulk bipartition to the one-dimensional Affleck-Kennedy-Lieb-Tasaki valence bond solid (VBS) states for the integer spin-S Haldane gapped phase, we can create an array of fractionalized spin-S/2 edge states with the super unit cell l in the reduced bulk system, and the topological properties encoded in the VBS wave functions can be revealed. The entanglement Hamiltonian (EH) with l = even corresponds to the quantum antiferromagnetic Heisenberg spin-S/2 model. For the even integer spins, the EH still describes the Haldane gapped phase. For the odd integer spins, however, the EH just corresponds to the quantum antiferromagnetic Heisenberg half-odd integer spin model with spinon excitations, characterizing the critical point separating the topological Haldane phase from the trivial gapped phase. Our results thus demonstrate that the topological bulk property not only determines its fractionalized edge states, but also the quantum criticality associated with the topological phase, where the elementary excitations are precisely those fractionalized edge degrees of freedom confined in the bulk of the topological phase.
D'Alberton, Franco; Assante, Maria Teresa; Foresti, Maura; Balsamo, Antonio; Bertelloni, Silvano; Dati, Eleonora; Nardi, Laura; Bacchi, Maria Letizia; Mazzanti, Laura
2015-06-01
Progressive care improvement for differences of sex development (DSD), regarding diagnosis communication, psychological, medical and surgical management has been claimed. To assess clinical management, quality of life (QoL) and the general psychosocial adjustment of individuals with 46,XY DSD. Some differences related to age at diagnosis are investigated. Cross-sectional study using standardized questionnaires. Forty-three Caucasian females with 46,XY DSD (self declared diagnoses: complete androgen insensitivity syndrome, n = 34; complete gonadal dysgenesis, n = 1; 5α-reductase deficiency, n = 4; Leydig cell hypoplasia, n = 1; unknown diagnosis, n = 3; age years: 31.5 ± 9.6 [range 18-57 years]). University Hospitals. Subjects were required to fill in questionnaires (ABCL, WHOQOL, dedicated 17-item questionnaire). Academic and socioeconomic data were compared with those of the Italian population. QoL and psychological data were compared with those of a comparison group (46,XX healthy females: n = 43; age, years: 34.5 ± 9.7, range 22-51 years). Present sample of women living with 46,XY DSD were well adapted and were higher achievers than controls, both in educational and professional life. They showed good QoL, but they appeared less satisfied in psychological and social areas. They had borderline mean scores and statistically higher scores than the comparison group for depression, anxiety, internalizing and externalizing problems. Younger persons living with a 46,XY DSD showed better psychosocial adjustment than older ones. Younger women showed lower age at diagnosis communication. Psychological support was more often proposed at the time of diagnosis communication to younger individuals, and they undertook it more frequently than older ones. Italian people living with 46,XY DSD were well adapted and successful; they reported a good QoL but showed higher degree of psychological distress than the comparison group. Lower psychological distress in younger women
Biallelic and monoallelic ESR2 variants associated with 46,XY disorders of sex development.
Baetens, Dorien; Güran, Tülay; Mendonca, Berenice B; Gomes, Nathalia L; De Cauwer, Lode; Peelman, Frank; Verdin, Hannah; Vuylsteke, Marnik; Van der Linden, Malaïka; Stoop, Hans; Looijenga, Leendert H; De Bosscher, Karolien; Cools, Martine; De Baere, Elfride
2017-10-26
PurposeDisorders or differences of sex development (DSDs) are rare congenital conditions characterized by atypical sex development. Despite advances in genomic technologies, the molecular cause remains unknown in 50% of cases.MethodsHomozygosity mapping and whole-exome sequencing revealed an ESR2 variant in an individual with syndromic 46,XY DSD. Additional cases with 46,XY DSD underwent whole-exome sequencing and targeted next-generation sequencing of ESR2. Functional characterization of the identified variants included luciferase assays and protein structure analysis. Gonadal ESR2 expression was assessed in human embryonic data sets and immunostaining of estrogen receptor-β (ER-β) was performed in an 8-week-old human male embryo.ResultsWe identified a homozygous ESR2 variant, c.541_543del p.(Asn181del), located in the highly conserved DNA-binding domain of ER-β, in an individual with syndromic 46,XY DSD. Two additional heterozygous missense variants, c.251G>T p.(Gly84Val) and c.1277T>G p.(Leu426Arg), located in the N-terminus and the ligand-binding domain of ER-β, were found in unrelated, nonsyndromic 46,XY DSD cases. Significantly increased transcriptional activation and an impact on protein conformation were shown for the p.(Asn181del) and p.(Leu426Arg) variants. Testicular ESR2 expression was previously documented and ER-β immunostaining was positive in the developing intestine and eyes.ConclusionOur study supports a role for ESR2 as a novel candidate gene for 46,XY DSD.Genetics in Medicine advance online publication, 26 October 2017; doi:10.1038/gim.2017.163.
Increased high-density lipoprotein cholesterol levels in mice with XX versus XY sex chromosomes.
Link, Jenny C; Chen, Xuqi; Prien, Christopher; Borja, Mark S; Hammerson, Bradley; Oda, Michael N; Arnold, Arthur P; Reue, Karen
2015-08-01
The molecular mechanisms underlying sex differences in dyslipidemia are poorly understood. We aimed to distinguish genetic and hormonal regulators of sex differences in plasma lipid levels. We assessed the role of gonadal hormones and sex chromosome complement on lipid levels using the four core genotypes mouse model (XX females, XX males, XY females, and XY males). In gonadally intact mice fed a chow diet, lipid levels were influenced by both male-female gonadal sex and XX-XY chromosome complement. Gonadectomy of adult mice revealed that the male-female differences are dependent on acute effects of gonadal hormones. In both intact and gonadectomized animals, XX mice had higher HDL cholesterol (HDL-C) levels than XY mice, regardless of male-female sex. Feeding a cholesterol-enriched diet produced distinct patterns of sex differences in lipid levels compared with a chow diet, revealing the interaction of gonadal and chromosomal sex with diet. Notably, under all dietary and gonadal conditions, HDL-C levels were higher in mice with 2 X chromosomes compared with mice with an X and Y chromosome. By generating mice with XX, XY, and XXY chromosome complements, we determined that the presence of 2 X chromosomes, and not the absence of the Y chromosome, influences HDL-C concentration. We demonstrate that having 2 X chromosomes versus an X and Y chromosome complement drives sex differences in HDL-C. It is conceivable that increased expression of genes escaping X-inactivation in XX mice regulates downstream processes to establish sexual dimorphism in plasma lipid levels. © 2015 American Heart Association, Inc.
Alsiraj, Yasir; Thatcher, Sean E; Charnigo, Richard; Chen, Kuey; Blalock, Eric; Daugherty, Alan; Cassis, Lisa A
2017-01-24
Abdominal aortic aneurysms (AAAs) are a deadly pathology with strong sexual dimorphism. Similar to humans, female mice exhibit far lower incidences of angiotensin II-induced AAAs than males. In addition to sex hormones, the X and Y sex chromosomes, and their unique complements of genes, may contribute to sexually dimorphic AAA pathology. Here, we defined the effect of female (XX) versus male (XY) sex chromosome complement on angiotensin II-induced AAA formation and rupture in phenotypically female mice. Female low-density lipoprotein receptor (Ldlr) deficient mice with an XX or XY sex chromosome complement were infused with angiotensin II for 28 days to induce AAAs. Abdominal aortic lumen diameters were quantified by ultrasound, whereas AAA diameters were quantified at study end point. DNA microarrays were performed on abdominal aortas. To mimic males, female mice were administered a single dose of testosterone as neonates or as adults before angiotensin II infusions. Female Ldlr-/- deficient mice with an XX and XY sex chromosome complement had similar sex organ weights and low serum testosterone concentrations. Abdominal aortas from female XY mice selectively expressed Y chromosome genes, whereas genes known to escape X inactivation were higher in XX females. The majority of aortic gene differences in XY versus XX females fell within inflammatory pathways. AAA incidences doubled and aneurysms ruptured in XY females. AAAs from XY females exhibited inflammation, and plasma interleukin-1β concentrations were increased in XY females. Moreover, aortas from XY females had augmented matrix metalloproteinase activity and increased oxidative stress. Last, testosterone exposure applied chronically, or as a single bolus at postnatal day 1, markedly worsened AAA outcomes in XY in comparison with XX adult females. An XY sex chromosome complement in phenotypic females profoundly influenced aortic gene expression profiles and promoted AAA severity. When XY females were exposed
Sun, Wen-Yang; Wang, Dong; Ye, Liu
2017-11-01
In this work, we investigate the dynamical properties of various quantum measures (quantum coherence and correlations) to estimate the system evolution under spin-1/2 Heisenberg XXZ model by utilizing quantum renormalization-group method. It has been shown that quantum coherence and correlations can be used to effectively detect a quantum critical point associated with a quantum phase transition (QPT) after several iterations of renormalization. Additionally, we obtain that the dynamical behavior of l1 norm of coherence is in agreement with that of concurrence and double trace distance discord. Interestingly, Bell-CHSH inequality cannot be violated with increasing of the spin system size N. That is, the block-block Bell nonlocality cannot be revealed. Moreover, we reveal some quantitative relations between quantum coherence and some quantum correlations, and thus the l1 norm of coherence is more conducive for probing the QPT at the critical point within the composite systems. Further, the scaling behaviors and nonanalytic phenomenon of the l1 norm of coherence and quantum discord are discussed in detail.
From four- to two-channel Kondo effect in junctions of XY spin chains
Energy Technology Data Exchange (ETDEWEB)
Giuliano, Domenico, E-mail: domenico.giuliano@fis.unical.it [Dipartimento di Fisica, Università della Calabria, Arcavacata di Rende I-87036, Cosenza (Italy); INFN, Gruppo collegato di Cosenza, Arcavacata di Rende I-87036, Cosenza (Italy); Sodano, Pasquale, E-mail: pasquale.sodano02@gmail.com [International Institute of Physics, Universidade Federal do Rio Grande do Norte, 59078-400 Natal, RN (Brazil); Departemento de Física Teorica e Experimental, Universidade Federal do Rio Grande do Norte, 59072-970 Natal, RN (Brazil); Tagliacozzo, Arturo, E-mail: arturo.tagliacozzo@na.infn.it [INFN, Gruppo collegato di Cosenza, Arcavacata di Rende I-87036, Cosenza (Italy); Dipartimento di Fisica, Università di Napoli “Federico II”, Monte S. Angelo-Via Cintia, I-80126 Napoli (Italy); CNR-SPIN, Monte S. Angelo-Via Cintia, I-80126 Napoli (Italy); Trombettoni, Andrea, E-mail: andreatr@sissa.it [CNR-IOM DEMOCRITOS Simulation Center, Via Bonomea 265, I-34136 Trieste (Italy); SISSA and INFN, Sezione di Trieste, Via Bonomea 265, I-34136 Trieste (Italy)
2016-08-15
We consider the Kondo effect in Y-junctions of anisotropic XY models in an applied magnetic field along the critical lines characterized by a gapless excitation spectrum. We find that, while the boundary interaction Hamiltonian describing the junction can be recasted in the form of a four-channel, spin-1/2 antiferromagnetic Kondo Hamiltonian, the number of channels effectively participating in the Kondo effect depends on the chain parameters, as well as on the boundary couplings at the junction. The system evolves from an effective four-channel topological Kondo effect for a junction of XX-chains with symmetric boundary couplings into a two-channel one at a junction of three quantum critical Ising chains. The effective number of Kondo channels depends on the properties of the boundary and of the bulk. The XX-line is a “critical” line, where a four-channel topological Kondo effect can be recovered by fine-tuning the boundary parameter, while along the line in parameter space connecting the XX-line and the critical Ising point the junction is effectively equivalent to a two-channel topological Kondo Hamiltonian. Using a renormalization group approach, we determine the flow of the boundary couplings, which allows us to define and estimate the critical couplings and Kondo temperatures of the different Kondo (pair) channels. Finally, we study the local transverse magnetization in the center of the Y-junction, eventually arguing that it provides an effective tool to monitor the onset of the two-channel Kondo effect.
From four- to two-channel Kondo effect in junctions of XY spin chains
Directory of Open Access Journals (Sweden)
Domenico Giuliano
2016-08-01
Full Text Available We consider the Kondo effect in Y-junctions of anisotropic XY models in an applied magnetic field along the critical lines characterized by a gapless excitation spectrum. We find that, while the boundary interaction Hamiltonian describing the junction can be recasted in the form of a four-channel, spin-1/2 antiferromagnetic Kondo Hamiltonian, the number of channels effectively participating in the Kondo effect depends on the chain parameters, as well as on the boundary couplings at the junction. The system evolves from an effective four-channel topological Kondo effect for a junction of XX-chains with symmetric boundary couplings into a two-channel one at a junction of three quantum critical Ising chains. The effective number of Kondo channels depends on the properties of the boundary and of the bulk. The XX-line is a “critical” line, where a four-channel topological Kondo effect can be recovered by fine-tuning the boundary parameter, while along the line in parameter space connecting the XX-line and the critical Ising point the junction is effectively equivalent to a two-channel topological Kondo Hamiltonian. Using a renormalization group approach, we determine the flow of the boundary couplings, which allows us to define and estimate the critical couplings and Kondo temperatures of the different Kondo (pair channels. Finally, we study the local transverse magnetization in the center of the Y-junction, eventually arguing that it provides an effective tool to monitor the onset of the two-channel Kondo effect.
Rivera, Mario; Caignan, Gregori A; Astashkin, Andrei V; Raitsimring, Arnold M; Shokhireva, Tatjana Kh; Walker, F Ann
2002-05-29
The (13)C pulsed ENDOR and NMR study of [meso-(13)C-TPPFe(OCH(3))(OO(t)Bu)](-) performed in this work shows that although the unpaired electron in low-spin ferrihemes containing a ROO(-) ligand resides in a d(pi) orbital at 8 K, the d(xy) electron configuration is favored at physiological temperatures. The variable temperature NMR spectra indicate a dynamic situation in which a heme with a d(pi) electron configuration and planar porphyrinate ring is in equilibrium with a d(xy) electron configuration that has a ruffled porphyrin ring. Because of the similarity in the EPR spectra of the hydroperoxide complexes of heme oxygenase, cytochrome P450, and the model heme complex reported herein, it is possible that these two electron configurations and ring conformations may also exist in equilibrium in the enzymatic systems. The ruffled porphyrinate ring would aid the attack of the terminal oxygen of the hydroperoxide intermediate of heme oxygenase (HO) on the meso-carbon, and the large spin density at the meso-carbons of a d(xy) electron configuration heme suggests the possibility of a radical mechanism for HO. The dynamic equilibrium between the ruffled (d(xy)) and planar (d(pi)) conformers observed in the model complexes also suggests that a flexible heme binding cavity may be an important structural motif for heme oxygenase activity.
Dufresnes, Christophe; Borzée, Amaël; Horn, Agnès; Stöck, Matthias; Ostini, Massimo; Sermier, Roberto; Wassef, Jérôme; Litvinchuck, Spartak N; Kosch, Tiffany A; Waldman, Bruce; Jang, Yikweon; Brelsford, Alan; Perrin, Nicolas
2015-09-01
Contrasting with birds and mammals, poikilothermic vertebrates often have homomorphic sex chromosomes, possibly resulting from high rates of sex-chromosome turnovers and/or occasional X-Y recombination. Strong support for the latter mechanism was provided by four species of European tree frogs, which inherited from a common ancestor (∼ 5 Ma) the same pair of homomorphic sex chromosomes (linkage group 1, LG1), harboring the candidate sex-determining gene Dmrt1. Here, we test sex linkage of LG1 across six additional species of the Eurasian Hyla radiation with divergence times ranging from 6 to 40 Ma. LG1 turns out to be sex linked in six of nine resolved cases. Mapping the patterns of sex linkage to the Hyla phylogeny reveals several transitions in sex-determination systems within the last 10 My, including one switch in heterogamety. Phylogenetic trees of DNA sequences along LG1 are consistent with occasional X-Y recombination in all species where LG1 is sex linked. These patterns argue against one of the main potential causes for turnovers, namely the accumulation of deleterious mutations on nonrecombining chromosomes. Sibship analyses show that LG1 recombination is strongly reduced in males from most species investigated, including some in which it is autosomal. Intrinsically low male recombination might facilitate the evolution of male heterogamety, and the presence of important genes from the sex-determination cascade might predispose LG1 to become a sex chromosome. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Rojas, Onofre; Strečka, J.; de Souza, S. M.
2016-11-01
The spin-1/2 Ising-Heisenberg two-leg ladder accounting for alternating Ising and Heisenberg inter-leg couplings in addition to the Ising intra-leg coupling is rigorously mapped onto to a mixed spin-(3/2,1/2) Ising-Heisenberg diamond chain with the nodal Ising spins S = 3 / 2 and the interstitial spin-1/2 Heisenberg dimers. The latter effective model with higher-order interactions between the nodal and interstitial spins is subsequently exactly solved within the transfer-matrix method. The model under investigation exhibits five different ground states: ferromagnetic, antiferromagnetic, superantiferromagnetic and two types of frustrated ground states with a non-zero residual entropy. A detailed study of thermodynamic properties reveals an anomalous specific-heat peak at low enough temperatures, which is strongly reminiscent because of its extraordinary height and sharpness to an anomaly accompanying a phase transition. It is convincingly evidenced, however, that the anomalous peak in the specific heat is finite and it comes from vigorous thermal excitations from a two-fold degenerate ground state towards a macroscopically degenerate excited state. Thermal entanglement between the nearest-neighbor Heisenberg spins is also comprehensively explored by taking advantage of the concurrence. The threshold temperature delimiting a boundary between the entangled and disentangled parameter space may show presence of a peculiar temperature reentrance.
Rocha, Vanessa Brito Campoy; Guerra-Júnior, Gil; Marques-de-Faria, Antonia Paula; de Mello, Maricilda Palandi; Maciel-Guerra, Andréa Trevas
2011-12-01
To determine the frequency of XY karyotypes among females with complete gonadal dysgenesis (CGD) and to investigate the frequency of both gonadal tumors and SRY mutations. Retrospective study based on data from all patients with CGD seen in our service from 1989 to 2010. Clinic for disorders of sex development, University Hospital, State University of Campinas. Thirty-two patients with hypergonadotropic hypogonadism, streak gonads, internal and external female genitalia, and normal karyotype (46,XX or 46,XY); 31 were index cases and 29 did not have a previously determined karyotype. None. None. The percentage of XY karyotypes among patients with CGD was 34.5% (10/29). Mean age at diagnosis among XY and XX patients was 17.4 years and 19.9 years, respectively. Gonadal tumors were found in 4 of 9 XY girls, and 7 of 10 had SRY gene mutations. The previously unreported finding of an elevated frequency of 46,XY karyotype among patients with CGD and the high risk of gonadal neoplasia in such cases indicate that this diagnosis must be kept in mind by clinicians and strengthen the importance of karyotype analysis in females with primary hypogonadism. In addition, the frequency of SRY mutations in XY CGD might be higher than previously considered. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Taketo, Teruko; Naumova, Anna K
2013-10-01
In the XY pachytene spermatocyte, the sex chromosomes do not synapse except for the pseudoautosomal region and become transcriptionally silenced. It has been suggested that the meiotic silencing of unsynapsed chromatin (MSUC) also occurs in oocytes. In the XY sex-reversed female mouse, the sex chromosomes fail to pair in the majority of oocytes and a greater number of oocytes are eliminated during the meiotic prophase compared to the XX female. Yet, many XY oocytes survive to reach the second meiotic metaphase. The goal of our current study was to determine whether the single X chromosome shows the characteristics of asynapsis and meiotic silencing in a proportion of XY oocytes, which can explain the survival of the remaining oocytes. We first examined the accumulation of markers associated with asynapsis or transcriptional silencing, i.e., BRCA1, γH2AX, H3K9me3, and H3K27me3, at the single X chromosome in the XY oocyte. We found that γH2AX and BRCA1 were enriched on the single X chromosome whereas H3K9me3 was not, and H3K27me3 was enriched at all chromosomes in the majority of XY oocytes. We next examined the meiotic silencing of the single X chromosome using enrichment of the X-encoded ATRX protein. On average, ATRX enrichment was lower in XY oocytes than in XX oocytes as expected from its half gene dosage. However, the intensity of ATRX staining in XY oocytes harboring γH2AX domains showed a remarkable heterogeneity. We conclude that MSUC occurs with varying consequences, resulting in a heterogeneous population of oocytes with respect to protein enrichment in the XY female mouse.
Xiao, F.; Möller, J. S.; Lancaster, T.; Williams, R. C.; Pratt, F. L.; Blundell, S. J.; Ceresoli, D.; Barton, A. M.; Manson, J. L.
2015-04-01
We present the results of muon-spin relaxation measurements of spin excitations in the one-dimensional quantum Heisenberg antiferromagnet Cu (pyz ) (NO3)2 . Using density-functional theory we propose muon sites and assess the degree of perturbation the muon probe causes on the system. We identify a site involving the muon forming a hydroxyl-type bond with an oxygen on the nitrate group that is sensitive to the characteristic spin dynamics of the system. Our measurements of the spin dynamics show that in the temperature range TNresponse to the fluctuation spectrum, to a regime where the muon detects early-time transport with a ballistic character. This behavior is contrasted with that found for T >J and that in the related two-dimensional system Cu (pyz) 2(ClO4)2 .
Vision Guided X-Y Table For Inspection
Chen, Michel J.
1983-05-01
This paper demonstrates an example of utilization of machine intelligence in automation. A system was developed to perform precision part inspection and automated workpiece handling. This system consists of a robot which is utilized to perform simple pick-and-place function, a MI VS-110 machine vision system which provides a vision library and the functions of masking and programmable image overlay, and an X-Y-θ table. This setup demonstrates a simplified approach to machine vision and automation. In this complete sensorimotor system, BASIC was the programming language to develop and integrate the control software for the inspection process by using the MI DS-100 machine vision development system. By calling vision functions, X-Y-θ table commands and simple robot commands, the task of parts" inspection under high- and low-resolution cameras, sorting, as well as disposition is shown to be easy to conceptualize and implement. This robot system can perform tasks without the necessity of prealigning or jigging workpieces. Numerous other applications can be accomplished by adopting a similar methodology.
Thermal Entanglement in XXZ Heisenberg Model for Coupled Spin-Half and Spin-One Triangular Cell
Najarbashi, Ghader; Balazadeh, Leila; Tavana, Ali
2018-01-01
In this paper, we investigate the thermal entanglement of two-spin subsystems in an ensemble of coupled spin-half and spin-one triangular cells, (1/2, 1/2, 1/2), (1/2, 1, 1/2), (1, 1/2, 1) and (1, 1, 1) with the XXZ anisotropic Heisenberg model subjected to an external homogeneous magnetic field. We adopt the generalized concurrence as the measure of entanglement which is a good indicator of the thermal entanglement and the critical points in the mixed higher dimensional spin systems. We observe that in the near vicinity of the absolute zero, the concurrence measure is symmetric with respect to zero magnetic field and changes abruptly from a non-null to null value for a critical magnetic field that can be signature of a quantum phase transition at finite temperature. The analysis of concurrence versus temperature shows that there exists a critical temperature, that depends on the type of the interaction, i.e. ferromagnetic or antiferromagnetic, the anisotropy parameter and the strength of the magnetic field. Results show that the pairwise thermal entanglement depends on the third spin which affects the maximum value of the concurrence at absolute zero and at quantum critical points.
Theory of the orthogonal dimer Heisenberg spin model for SrCu sub 2 (BO sub 3) sub 2
Miyahara, S
2003-01-01
The magnetic properties of SrCu sub 2 (BO sub 3) sub 2 are reviewed from a theoretical point of view. SrCu sub 2 (BO sub 3) sub 2 is a new two-dimensional spin gap system and its magnetic properties are well described by a spin-1/2 antiferromagnetic Heisenberg model of the orthogonal dimer lattice. The model has a dimer singlet ground state whose exactness was proven by Shastry and Sutherland for a topologically equivalent model more than 20 years ago. The exactness of the ground state is maintained even if interlayer couplings are introduced for SrCu sub 2 (BO sub 3) sub 2. In the two-dimensional model, quantum phase transitions take place between different ground states for which three phases are expected: a gapped dimer singlet state, a plaquette resonating valence bond state and a gapless magnetic ordered state. Analysis of the experimental data shows that the dimer singlet ground state is realized in SrCu sub 2 (BO sub 3) sub 2. The orthogonality of the dimer bonds, which is the underlying symmetry of th...
Strečka, Jozef; Richter, Johannes; Derzhko, Oleg; Verkholyak, Taras; KarÄ¾ová, Katarína
2017-06-01
The spin-1/2 Heisenberg octahedral chain with regularly alternating monomeric and square-plaquette sites is investigated using various analytical and numerical methods: variational technique, localized-magnon approach, exact diagonalization (ED), and density-matrix renormalization group (DMRG) methods. The model belongs to the class of flatband systems and it has a rich ground-state phase diagram including phases with spontaneously broken translational symmetry. Moreover, it exhibits an anomalous low-temperature thermodynamics close to continuous or discontinuous field-driven quantum phase transitions between three quantum ferrimagnetic phases, tetramer-hexamer phase, monomer-tetramer phase, localized-magnon phase, and two different spin-liquid phases. If the intraplaquette coupling is at least twice as strong as the monomer-plaquette coupling, the variational method furnishes a rigorous proof of the monomer-tetramer ground state in a low-field region and the localized-magnon approach provides exact evidence of a single magnon trapped at each square plaquette in a high-field region. In the rest of the parameter space we have numerically studied the ground-state phase diagram and magnetization process using DMRG and ED methods. It is shown that the zero-temperature magnetization curve may involve up to four intermediate plateaus at zero, one-fifth, two-fifths, and three-fifths of the saturation magnetization, while the specific heat exhibits a striking low-temperature peak in the vicinity of discontinuous quantum phase transitions.
Saadatmand, S. N.; McCulloch, I. P.
2017-08-01
We present new numerical tools to analyze symmetry-broken phases in the context of SU (2 ) -symmetric translation-invariant matrix product states (MPS) and density-matrix renormalization-group (DMRG) methods for infinite cylinders, and determine the phase diagram of the geometrically frustrated triangular Heisenberg model with nearest- and next-nearest-neighbor (NN and NNN) interactions. The appearance of Nambu-Goldstone modes in the excitation spectrum is characterized by "tower of states" levels in the momentum-resolved entanglement spectrum. Symmetry-breaking phase transitions are detected by a combination of the correlation lengths and second and fourth cumulants of the magnetic order parameters (which we call the Binder ratio), even though symmetry implies that the order parameter itself is strictly zero. Using this approach, we have identified a 120∘ order, a columnar order, and an algebraic spin liquid (specific to width-6 systems), alongside the previously studied topological spin liquid phase. For the latter, we also demonstrate robustness against chiral perturbations.
Mulheres XY e a Síndrome de Insensibilidade aos Andrógenos
Directory of Open Access Journals (Sweden)
João Edson Marques Bandeira
2015-06-01
Full Text Available Objective: The aims are to report a case of Androgen-Insensitivity Syndrome (AIS and discuss aspects of opportune diagnosis and treatment of AIS. Case Report: C.F.F., 35, sought medical assistance reporting overweight and hypertension. During the anamnesis did not present menarche; with normal breast development, but late, around 14 years. Physical examination shows normal female external genitalia, with scarce pubic hair (P2 and the absence of axillary hair; breasts with normal development (M5. Conclusions: The result of the G band karyotype was 46, XY for the sisters and the screening in relatives revealed prepubescent girl with XY karyotype. The risk of tumor development is difficult to be predicted recently markers were identified that may be useful in determining individual risk and suggest the time of gonadectomy. The current consensus on the approach related to intersex disorders recommends gonadectomy at diagnosis for patients with AIS, after puberty, due to the ease of hormone replacement.
Case of 46,XX/47,XY, +21 chimerism in a newborn infant with ambiguous genitalia
Energy Technology Data Exchange (ETDEWEB)
Sawai, Tomoko; Yoshimoto, Masaaki; Kinoshita, Ei-ichi; Baba, Tsuneyoshi; Matsumoto, Tadashi; Tsuji, Yoshiro, Niikawa, Norio [Nagasaki Univ. School of Medicine, Nagasaki (Japan); Fukuda, Shinpei [Ohmura Municipal Hospital, Ohmura (Japan); Harada, Naoki [Kyushu Medical Science, Nagasaki (Japan)
1994-02-15
The authors describe the whole-body chimerism in a newborn infant with small phallus, pseudo-vaginal perineal hypospadias, and a bifid scrotum containing gonads. The human testis determining factor gene (SRY) was detected by PCR amplification. GTG-banding chromosome analysis in peripheral blood lymphocytes and cultured fibroblasts derived from right cubital skin showed a 46,XX/47,XY, +21 karyotype. Their ratios in each cell line were 294:5 and 178:7, respectively. QFQ-banding chromosome analysis documented 3 heteromorphic satellites on trisomic chromsomes 21 in the 47,XY,+21 cell line and a homozygous satellite pattern in the 46,XX cell line. Heteromorphic patterns of chromsomes 4, 13, 14, and 22 were also different between the two cell lines. To our knowledge, such disomy/trisomy chimeras have not been described previously. 10 refs., 3 figs.
Skew information in the XY model with staggered Dzyaloshinskii-Moriya interaction
Energy Technology Data Exchange (ETDEWEB)
Qiu, Liang, E-mail: lqiu@cumt.edu.cn [School of Physics, China University of Mining and Technology, Xuzhou, Jiangsu 221116 (China); Quan, Dongxiao [State Key Laboratory of Integrated Services Networks, Xidian University, Xi' an, Shaanxi 710071 (China); Pan, Fei; Liu, Zhi [School of Physics, China University of Mining and Technology, Xuzhou, Jiangsu 221116 (China)
2017-06-01
We study the performance of the lower bound of skew information in the vicinity of transition point for the anisotropic spin-1/2 XY chain with staggered Dzyaloshinskii-Moriya interaction by use of quantum renormalization-group method. For a fixed value of the Dzyaloshinskii-Moriya interaction, there are two saturated values for the lower bound of skew information corresponding to the spin-fluid and Néel phases, respectively. The scaling exponent of the lower bound of skew information closely relates to the correlation length of the model and the Dzyaloshinskii-Moriya interaction shifts the factorization point. Our results show that the lower bound of skew information can be a good candidate to detect the critical point of XY spin chain with staggered Dzyaloshinskii-Moriya interaction.
46,XY female sex reversal syndrome with bilateral gonadoblastoma and dysgerminoma.
DU, Xue; Zhang, Xuhong; Li, Yongmei; Han, Yukun
2014-10-01
Sex reversal syndrome is a rare congenital condition of complete or disordered gonadal development leading to discordance between the genetic, gonadal and phenotypic sexes, including 46,XX and 46,XY. The gonadoblastoma on the Y-chromosome (GBY) region is associated with an increased risk of developing type II germ cell tumors/cancer. The present study reports a unique case of a phenotypically normal female (age 17 years), presenting with primary amenorrhea and later diagnosed with 46,XY female sex reversal syndrome. Following bilateral gonadectomy, bilateral gonadoblastoma and dysgerminoma were diagnosed. Thus, estrogen replacement therapy was administered periodically to promote the development of secondary sexual characteristics and menstruation, and to prevent osteoporosis. A four year follow-up showed no tumor recurrence and a regular menstrual cycle in this patient.
Thermodynamics of the two-dimensional XY model from functional renormalization
Jakubczyk, Pawel
2016-01-01
We solve the nonperturbative renormalization-group flow equations for the two-dimensional XY model at the truncation level of the (complete) second-order derivative expansion. We compute the thermodynamic properties in the high-temperature phase and compare the non-universal features specific to the XY model with results from Monte Carlo simulations. In particular, we study the position and magnitude of the specific heat peak as a function of temperature. The obtained results compare well with Monte Carlo simulations. We additionally gauge the accuracy of simplified nonperturbative renormalization-group treatments relying on $\\phi^4$-type truncations. Our computation indicates that such an approximation is insufficient in the high-$T$ phase and a correct analysis of the specific heat profile requires account of an infinite number of interaction vertices.
Rodrigues, F. C.; de Souza, S. M.; Rojas, Onofre
2017-04-01
Motivated by the recent discoveries of some compounds such as the Bi2Fe4O9 which crystallizes in an orthorhombic crystal structure with the Fe3+ ions, and iron-based oxyfluoride Bi4Fe5O13 F compounds following the pattern of Cairo pentagonal structure, among some other compounds. We propose a model for one stripe of the Cairo pentagonal Ising-Heisenberg lattice, one of the edges of a pentagon is different, and this edge will be associated with a Heisenberg exchange interaction, while the Ising exchange interactions will associate the other edges. We study the phase transition at zero temperature, illustrating five phases: a ferromagnetic phase (FM), a dimer antiferromagnetic (DAF), a plaquette antiferromagnetic (PAF), a typical antiferromagnetic (AFM) and a peculiar frustrated phase (FRU) where two types of frustrated states with the same energy coexist. To obtain the partition function of this model, we use the transfer matrix approach and following the eight vertex model notation. Using this result we discuss the specific heat, internal energy and entropy as a function of the temperature, and we can observe some unexpected behavior in the low-temperature limit, such as anomalous double peak in specific heat due to the existence of three phase (FRU, PAF(AFM) and FM) transitions occurring in a close region to each other. Consequently, the low-lying energy thermal excitation generates this double anomalous peak, and we also discuss the internal energy at the low temperature limit, where this double peak curve occurs. Some properties of our result were compared with two dimensional Cairo pentagonal lattices, as well as orthogonal dimer plaquette Ising-Heisenberg chain.
Scaling of quantum Fisher information close to the quantum phase transition in the XY spin chain
Energy Technology Data Exchange (ETDEWEB)
Ye, En-Jia, E-mail: yeenjia@jiangnan.edu.cn [Jiangsu Provincial Research Center of Light Industrial Optoelectronic Engineering and Technology, School of Science, Jiangnan University, Wuxi 214122 (China); Hu, Zheng-Da [Jiangsu Provincial Research Center of Light Industrial Optoelectronic Engineering and Technology, School of Science, Jiangnan University, Wuxi 214122 (China); Wu, Wei [Zhejiang Institute of Modern Physics and Physics Department, Zhejiang University, Hangzhou 310027 (China)
2016-12-01
The quantum phase transition of an XY spin chain is investigated by employing the quantum Fisher information encoded in the ground state. It is shown that the quantum Fisher information is an effective tool for characterizing the quantum criticality. The quantum Fisher information, its first and second derivatives versus the transverse field display the phenomena of sudden transition, sudden jump and divergence, respectively. Besides, the analysis of finite size scaling for the second derivative of quantum Fisher information is performed.
Tata Laksana Kasus Perempuan dengan Pure Gonadal Dysgenesis 46, XY (Sindrom Swyer)
Kanadi Sumapradja; Mila Maidarti; Achmad K. Harzif; Budi Wiweko; Gita Pratama; Muharam Natadisastra; Andon Hestiantoro
2016-01-01
Disorders of sex development (DSD) adalah kelainan medis yang dikaitkan dengan ketidakcocokan antara kromosom, gonad dan fenotip. Sindrom Swyer adalah kelainan berupa disgenesis gonad 46,XY dan diikuti dengan tidak terjadinya pelepasan anti-mullerian hormone (AMH) dari gonad yang mengalami disgenesis sehingga mengakibatkan berkembangnya duktus muller menjadi uterus. Keadaan tersebut mengakibatkan pasien mengeluh amenorea primer dan organ seks sekunder tidak berkembang. Orientasi gender umumn...
Genetic mutations and somatic anomalies in association with 46,XY gonadal dysgenesis.
Bastian, Claire; Muller, Jean-Baptiste; Lortat-Jacob, Stephen; Nihoul-Fékété, Claire; Bignon-Topalovic, Joelle; McElreavey, Ken; Bashamboo, Anu; Brauner, Raja
2015-05-01
To assess genetic mutations and associated somatic anomalies in a series of patients with 46,XY gonadal dysgenesis (GD). Single center retrospective study. University pediatric hospital. Fourteen patients with 46,XY GD. None. Genotype-phenotype relationship. The presenting symptom was disorders of sex development (6 patients), primary amenorrhea (2 patients), discordance between 46,XY karyotype and female external genitalia (3 patients), discovery of Müllerian structures at surgery (2 patients), or diagnosed in the evaluation of a gonadal tumor (1 patient). Müllerian structures were shown by ultrasound evaluation in 7 of 13 patients, genitography in 3 of 6 patients and/or surgery in 8 of 10 patients (3 not seen at imaging), or only by histologic examination (1 patient). Three patients had gonadoblastoma and/or seminoma. A mutation was found in 7 patients of whom 2 had family history of reproductive problems and 5 had associated somatic anomalies. The mutations were FOG2/ZFPM2 (1 patient), SRY (2 patients), WT1 (1 patient), or deletions of distal chromosome 9p (3 patients). Among the three other patients with associated anomalies and no mutation, two had ectodermal dysplasia and one had leukemia. Mutations were observed in half of the patients with 46,XY GD with Müllerian structures. We also describe for the first time the association between GD and ectodermal dysplasia. Müllerian structures can be found in some cases only by histologic examination, which should be coupled to preventive gonadectomy because of the risk of tumor formation. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Clinical Features of 32 Patients with XO/XY Gonadal Dysgenesis.
Jiang, Jian-Fa; Tian, Qin-Jie; Xue, Wei; Deng, Yan; Zheng, Ting-Ping; Sun, Ai-Jun
2016-08-01
Objective To summarize the clinical features of XO/XY gonadal dysgenesis. Method We retrospectively analyzed the clinical data of patients with XO/XY gonadal dysgenesis admitted to Peking Union Medical College Hospital from January 2008 to May 2015. Results Totally 32 patients with XO/XY gonadal dysgenesis were included. The social gender was female in all subjects and the age 6 to 33 years. Patients presented mainly with primary amenorrhea or short stature,and usually had specific somatic signs of Turner's syndrome. The breast development of 27 patients (84.38%) was less than level 3. The armpit hair was sparse or absent in 28 patients (87.5%) and the pubic hair was sparse or absent in 26 patients (81.25%).Other findings include naive vulva (n=18,56.25%)) and enlarged clitoris (n=5,15.63%). The average level of follicle stimulating hormone was (78.56±35.62) mIU/ml,the luteinizing hormone level was (20.23±11.35) mIU/ml,the estradiol level was (9.94±8.21) pg/ml,and the testosterone level was (0.24±0.18) ng/ml. All patients received prophylactic gonadectomy. The histopathology results showed a variety of gonads,and gonadal malignancy were observed in 4 patients.Conclusions Patients with XO/XY gonadal dysgenesis manifest primary amenorrhea or short stature,poorly developed secondary sexual characteristics,and elevated gonadotropin level. The gonads have increased risk of gonadal malignancy.
De La Rosa Gomez, Alejandro; MacKay, Niall; Regelskis, Vidas
2017-04-01
We present a general method of folding an integrable spin chain, defined on a line, to obtain an integrable open spin chain, defined on a half-line. We illustrate our method through two fundamental models with sl2 Lie algebra symmetry: the Heisenberg XXX and the Inozemtsev hyperbolic spin chains. We obtain new long-range boundary Hamiltonians and demonstrate that they exhibit Yangian symmetries, thus ensuring integrability of the models we obtain. The method presented provides a ;bottom-up; approach for constructing integrable boundaries and can be applied to any spin chain model.
Magnetismo em duas dimensões do modelo de Heisenberg anisotropico
Reinehr, Edson Eduardo
1994-01-01
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciencias Fisicas e Matematicas Neste trabalho determinamos a dependência da magnetização em função da temperatura para modelo de Heisenberg anisotrópico em duas dimensões, através do formalismo das funções de Green. Comparamos nossos resultados com os obtidos através de grupo de renormalização no espaço real e com resultados experimentais realizados em filmes finos. Também, neste trabalho, aplicamos o grupo de renor...
Abgaryan, V. S.; Ananikian, N. S.; Ananikyan, L. N.; Hovhannisyan, V. V.
2015-12-01
We consider the quasi-one dimensional spin-1 Ising-Heisenberg model with single-ion anisotropy on a diamond chain. Due to the exact solution of the model, we constructed the ground state phases which, alongside to others, have shown capability to exhibit most interesting frustrated state. The investigation of the magnetization processes showed enrichment of possibilities to form plateaus at zero, one- and two-thirds of the saturation magnetization. Negativity as a measure of the quantum entanglement is considered at low temperatures.
Multipartite quantum correlations in the extended J1-J2 Heisenberg model
Batle, J.; Tarawneh, O.; Nagata, Koji; Nakamura, Tadao; Abdalla, S.; Farouk, Ahmed
2017-11-01
Multipartite entanglement and the maximum violation of Bell inequalities are studied in finite clusters of spins in an extended J1-J2 Heisenberg model at zero temperature. The ensuing highly frustrated states will unveil a rich structure for different values of the corresponding spin-spin interaction strengths. The interplay between nearest-neighbors, next-nearest neighbors and further couplings will be explored using multipartite correlations. The model is relevant to certain quantum annealing computation architectures where an all-to-all connectivity is considered.
Excitations of breathers and rogue wave in the Heisenberg spin chain
Qi, Jian-Wen; Duan, Liang; Yang, Zhan-Ying; Yang, Wen-Li
2018-01-01
We study the excitations of breathers and rogue wave in a classical Heisenberg spin chain with twist interaction, which is governed by a fourth-order integrable nonlinear Schrödinger equation. The dynamics of these waves have been extracted from an exact solution. In particular, the corresponding existence conditions based on the parameters of perturbation wave number K, magnon number N, background wave vector ks and amplitude c are presented explicitly. Furthermore, the characteristics of magnetic moment distribution corresponding to these nonlinear waves are also investigated in detail. Finally, we discussed the state transition of three types nonlinear localized waves under the different excitation conditions.
Quantum Heisenberg antiferromagnetic chains with exchange and single-ion anisotropies
Energy Technology Data Exchange (ETDEWEB)
Peters, D; Selke, W [Institut fuer Theoretische Physik, RWTH Aachen University and JARA-SIM, 52056 Aachen (Germany); McCulloch, I P, E-mail: selke@physik.rwth-aachen.d [Department of Physics, University of Queensland, Brisbane, QLD 4072 (Australia)
2010-01-01
Using density matrix renormalization group calculations, ground state properties of the spin-1 Heisenberg chain with exchange and quadratic single-ion anisotropies in an external field are studied, for special choices of the two kinds of anisotropies. In particular, the phase diagram includes antiferromagnetic, spin-liquid (or spin-flop), IS2, and supersolid (or biconical) phases. Especially, new features of the spin-liquid and supersolid phases are discussed. Properties of the quantum chains are compared to those of corresponding classical spin chains.
Chaos and correspondence in classical and quantum Hamiltonian ratchets: a Heisenberg approach.
Pelc, Jordan; Gong, Jiangbin; Brumer, Paul
2009-06-01
Previous work [Gong and Brumer, Phys. Rev. Lett. 97, 240602 (2006)] motivates this study as to how asymmetry-driven quantum ratchet effects can persist despite a corresponding fully chaotic classical phase space. A simple perspective of ratchet dynamics, based on the Heisenberg picture, is introduced. We show that ratchet effects are in principle of common origin in classical and quantum mechanics, although full chaos suppresses these effects in the former but not necessarily the latter. The relationship between ratchet effects and coherent dynamical control is noted.
Energy Technology Data Exchange (ETDEWEB)
Belgiorno, Francesco [Politecnico di Milano, Dipartimento di Matematica, Milano (Italy); INdAM-GNFM, Milano (Italy); Cacciatori, Sergio L. [Universita dell' Insubria, Department of Science and High Technology, Como (Italy); INFN sezione di Milano, Milano (Italy); Dalla Piazza, Francesco [Universita ' ' La Sapienza' ' , Dipartimento di Matematica, Roma (Italy); Doronzo, Michele [Universita dell' Insubria, Department of Science and High Technology, Como (Italy)
2016-06-15
We investigate the quantisation in the Heisenberg representation of a model which represents a simplification of the Hopfield model for dielectric media, where the electromagnetic field is replaced by a scalar field φ and the role of the polarisation field is played by a further scalar field ψ. The model, which is quadratic in the fields, is still characterised by a non-trivial physical content, as the physical particles correspond to the polaritons of the standard Hopfield model of condensed matter physics. Causality is also taken into account and a discussion of the standard interaction representation is also considered. (orig.)
A TBA approach to thermal transport in the XXZ Heisenberg model
Zotos, X.
2017-10-01
We show that the thermal Drude weight and magnetothermal coefficient of the 1D easy-plane Heisenberg model can be evaluated by an extension of the Bethe ansatz thermodynamics formulation by Takahashi and Suzuki (1972 Prog. Theor. Phys. 48 2187). They have earlier been obtained by the quantum transfer matrix method (Klümper 1999 Z. Phys. B 91 507). Furthermore, this approach can be applied to the study of the far-out of equilibrium energy current generated at the interface between two semi-infinite chains held at different temperatures.
Energy Technology Data Exchange (ETDEWEB)
Gong, Jia-Min, E-mail: jmgong@yeah.net [School of Electronic Engineering, Xi' an University of Posts and Telecommunications, Xi' an 710121 (China); Tang, Qi [School of Electronic Engineering, Xi' an University of Posts and Telecommunications, Xi' an 710121 (China); Sun, Yu-Hang [School of Science, Xi' an University of Posts and Telecommunications, Xi' an 710121 (China); Qiao, Lin [School of Electronic Engineering, Xi' an University of Posts and Telecommunications, Xi' an 710121 (China)
2015-03-15
We studied the trace distance, the Hellinger distance, and the Bures distance geometric quantum discords (GQDs) for a two-spin Heisenberg XX chain with the Dzyaloshinsky–Moriya (DM) interaction and the external magnetic fields. We found that considerable enhancement of the GQDs can be achieved by introducing the DM interaction, and their maxima were obtained when the strength of the DM interaction approaches infinity. The external magnetic fields and the increase of the temperature can also enhance the GQDs to some extent during certain specific parameter regions.
El desconocido papel de Heisenberg en la carrera por obtener la bomba atómica
Beléndez Vázquez, Augusto; Arribas Garde, Enrique
2015-01-01
A finales del siglo XIX y comienzos del XX, Alemania era una potencia mundial en el campo de la Física; sin embargo, cuando Hitler comenzó a perseguir a los judíos, muchos de los científicos que habían hecho brillar a Alemania, que eran de origen judío, decidieron exiliarse y marcharon fundamentalmente a Estados Unidos. Pero otros físicos eran considerados totalmente «arios» según la doctrina nazi. Uno de ellos, Werner Karl Heisenberg, nacido a finales del primer año del siglo XX en la ciudad...
Spin-Lattice-Coupled Order in Heisenberg Antiferromagnets on the Pyrochlore Lattice.
Aoyama, Kazushi; Kawamura, Hikaru
2016-06-24
Effects of local lattice distortions on the spin ordering are investigated for the antiferromagnetic classical Heisenberg model on the pyrochlore lattice. It is found by Monte Carlo simulations that the spin-lattice coupling (SLC) originating from site phonons induces a first-order transition into two different types of collinear magnetic ordered states. The state realized at the stronger SLC is cubic symmetric characterized by the magnetic (1/2,1/2,1/2) Bragg peaks, while that at the weaker SLC is tetragonal symmetric characterized by the (1,1,0) ones, each accompanied by the commensurate local lattice distortions. Experimental implications to chromium spinels are discussed.
Ben Hadj Hmida, Imen; Mougou-Zerelli, Soumaya; Hadded, Anis; Dimassi, Sarra; Kammoun, Molka; Bignon-Topalovic, Joelle; Bibi, Mohamed; Saad, Ali; Bashamboo, Anu; McElreavey, Ken
2016-07-01
To determine the genetic cause of 46,XY primary amenorrhea in three 46,XY girls. Whole exome sequencing. University cytogenetics center. Three patients with unexplained 46,XY primary amenorrhea were included in the study. Potentially pathogenic variants were confirmed by Sanger sequencing, and familial segregation was determined where parents' DNA was available. Exome sequencing was performed in the three patients, and the data were analyzed for potentially pathogenic mutations. The functional consequences of mutations were predicted. Three novel homozygous nonsense mutations in the luteinizing hormone receptor (LHCGR) gene were identified:c.1573 C→T, p.Gln525Ter, c.1435 C→T p.Arg479Ter, and c.508 C→T, p.Gln170Ter. Inactivating mutations of the LHCGR gene may be a more common cause of 46,XY primary amenorrhea than previously considered. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Behavioural Problems in Children with 46XY Disorders of Sex Development
Directory of Open Access Journals (Sweden)
Nalini M. Selveindran
2017-01-01
Full Text Available The aim of this study is to determine the behavioural problems of children with 46XY disorders of sex development (DSD with genital ambiguity and to identify the risk factors that may influence behaviour. The 27 participants (aged 6–18 years consisted of 21 patients raised as boys and 6 patients raised as girls. Control data were obtained from a representative sibling of each patient who was matched for age and gender. The study tool used was the Child Behaviour Checklist (CBCL, which is a parent-administered questionnaire. The analysis of the behavioural scores revealed that the patient group had poorer scores in the total, externalizing, and internalizing realms. This group also had poorer scores in the anxious-depressed, social, and rule-breaking realms as compared to the control group. In addition, the XY-F group had higher scores (more pathological than the XY-M group, although the difference in the scores was not statistically significant. A comparison of the prevalence of patients with scores in the clinical range with that of the control group was not statistically significant. These findings support the current recommendations that psychological counselling should be an integral part of the professional support offered to patients with DSD.
Exome sequencing for the diagnosis of 46,XY disorders of sex development.
Baxter, Ruth M; Arboleda, Valerie A; Lee, Hane; Barseghyan, Hayk; Adam, Margaret P; Fechner, Patricia Y; Bargman, Renee; Keegan, Catherine; Travers, Sharon; Schelley, Susan; Hudgins, Louanne; Mathew, Revi P; Stalker, Heather J; Zori, Roberto; Gordon, Ora K; Ramos-Platt, Leigh; Pawlikowska-Haddal, Anna; Eskin, Ascia; Nelson, Stanley F; Délot, Emmanuèle; Vilain, Eric
2015-02-01
Disorders of sex development (DSD) are clinical conditions where there is a discrepancy between the chromosomal sex and the phenotypic (gonadal or genital) sex of an individual. Such conditions can be stressful for patients and their families and have historically been difficult to diagnose, especially at the genetic level. In particular, for cases of 46,XY gonadal dysgenesis, once variants in SRY and NR5A1 have been ruled out, there are few other single gene tests available. We used exome sequencing followed by analysis with a list of all known human DSD-associated genes to investigate the underlying genetic etiology of 46,XY DSD patients who had not previously received a genetic diagnosis. Samples were either submitted to the research laboratory or submitted as clinical samples to the UCLA Clinical Genomic Center. Sequencing data were filtered using a list of genes known to be involved in DSD. We were able to identify a likely genetic diagnosis in more than a third of cases, including 22.5% with a pathogenic finding, an additional 12.5% with likely pathogenic findings, and 15% with variants of unknown clinical significance. Early identification of the genetic cause of a DSD will in many cases streamline and direct the clinical management of the patient, with more focused endocrine and imaging studies and better-informed surgical decisions. Exome sequencing proved an efficient method toward such a goal in 46,XY DSD patients.
Differential lactate and cholesterol synthetic activities in XY and XX Sertoli cells
Shishido, Yurina; Baba, Takashi; Sato, Tetsuya; Shima, Yuichi; Miyabayashi, Kanako; Inoue, Miki; Akiyama, Haruhiko; Kimura, Hiroshi; Kanai, Yoshiakira; Ishihara, Yasuhiro; Haraguchi, Shogo; Miyazaki, Akira; Rozman, Damjana; Yamazaki, Takeshi; Choi, Man-Ho; Ohkawa, Yasuyuki; Suyama, Mikita; Morohashi, Ken-ichirou
2017-01-01
SRY, a sex-determining gene, induces testis development in chromosomally female (XX) individuals. However, mouse XX Sertoli cells carrying Sry (XX/Sry Sertoli cells) are incapable of fully supporting germ cell development, even when the karyotype of the germ cells is XY. While it has therefore been assumed that XX/Sry Sertoli cells are not functionally equivalent to XY Sertoli cells, it has remained unclear which specific functions are affected. To elucidate the functional difference, we compared the gene expression of XY and XX/Sry Sertoli cells. Lactate and cholesterol metabolisms, essential for nursing the developing germ cells, were down-regulated in XX/Sry cells, which appears to be caused at least in part by the differential expression of histone modification enzymes SMCX/SMCY (H3K4me3 demethylase) and UTX/UTY (H3K27me3 demethylase) encoded by the sex chromosomes. We suggest that down-regulation of lactate and cholesterol metabolism that may be due to altered epigenetic modification affects the nursing functions of XX/Sry Sertoli cells. PMID:28150810
Luo, Daji; Liu, Yun; Chen, Ji; Xia, Xiaoqin; Cao, Mengxi; Cheng, Bin; Wang, Xuejuan; Gong, Wuming; Qiu, Chao; Zhang, Yunsheng; Cheng, Christopher Hon Ki; Zhu, Zuoyan; Hu, Wei
2015-09-14
Medaka is an ideal model for sex determination and sex reversal, such as XY phenotypically female patients in humans. Here, we assembled improved TALENs targeting the DMY gene and generated XY(DMY-) mutants to investigate gonadal dysgenesis in medaka. DMY-TALENs resulted in indel mutations at the targeted loci (46.8%). DMY-nanos3UTR-TALENs induced mutations were passed through the germline to F1 generation with efficiencies of up to 91.7%. XY(DMY-) mutants developed into females, laid eggs, and stably passed the Y(DMY-) chromosome to next generation. RNA-seq generated 157 million raw reads from WT male (WT_M_TE), WT female (WT_F_OV) and XY(DMY-) female medaka (TA_F_OV) gonad libraries. Differential expression analysis identified 144 up- and 293 down-regulated genes in TA_F_OV compared with WT_F_OV, 387 up- and 338 down-regulated genes in TA_F_OV compared with WT_M_TE. According to genes annotation and functional prediction, such as Wnt1 and PRCK, it revealed that incomplete ovarian function and reduced fertility of XY(DMY-) mutant is closely related to the wnt signaling pathway. Our results provided the transcriptional profiles of XY(DMY-) mutants, revealed the mechanism between sex reversal and DMY in medaka, and suggested that XY(DMY-) medaka was a novel mutant that is useful for investigating gonadal dysgenesis in phenotypic female patients with the 46, XY karyotype.
Analysis of the Wilms' tumor suppressor gene (WT1) in patients 46,XY disorders of sex development.
Köhler, B; Biebermann, H; Friedsam, V; Gellermann, J; Maier, R F; Pohl, M; Wieacker, P; Hiort, O; Grüters, A; Krude, H
2011-07-01
The Wilms' tumor suppressor gene (WT1) is one of the major regulators of early gonadal and kidney development. WT1 mutations have been identified in 46,XY disorders of sex development (DSD) with associated kidney disease and in few isolated forms of 46,XY DSD. The objective of the study was the evaluation of WT1 mutations in different phenotypes of isolated 46,XY DSD and clinical consequences. The design of the study was: 1) sequencing of the WT1 gene in 210 patients with 46,XY DSD from the German DSD network, consisting of 150 males with severe hypospadias (70 without cryptorchidism, 80 with at least one cryptorchid testis), 10 males with vanishing testes syndrome, and 50 raised females with partial to complete 46,XY gonadal dysgenesis; and 2) genotype-phenotype correlation of our and all published patients with 46,XY DSD and WT1 mutations. We have detected WT1 mutations in six of 80 patients with severe hypospadias (7.5%) and at least one cryptorchid testis and in one of 10 patients with vanishing testes syndrome (10%). All patients except one developed Wilms' tumor and/or nephropathy in childhood or adolescence. WT1 analysis should be performed in newborns with complex hypospadias with at least one cryptorchid testis and in isolated 46,XY partial to complete gonadal dysgenesis. Kidney disease might not develop until later life in these cases. WT1 analysis is mandatory in all 46,XY DSD with associated kidney disease. WT1 analysis is not indicated in newborns with isolated hypospadias without cryptorchidism. Patients with WT1 mutations should be followed up closely because the risk of developing a Wilms' tumor, nephropathy, and/or gonadal tumor is very high.
Hu, Siyan; Tsai, Shan-Ho; Landau, D. P.
2014-03-01
We use Monte Carlo simulations to study the XXZ Heisenberg antiferromagnet in a field in order to clearly determine the nature of the multicritical point. We use a hybrid sampling method with Metropolis and Wolff-cluster algorithms, along with histogram reweighting techniques. Staggered magnetization susceptibilities, Binder cumulants, and finite-size scaling are considered in an effort to detect a possible biconical phase. An analysis of the probability distribution of the magnetization allowed us to conclude that the multicritical point is bicritical and it is in the three-dimensional Heisenberg universality class.
Meiotic behaviour and sperm aneuploidy in an infertile man with a mosaic 45,X/46,XY karyotype.
Ren, He; Chow, Victor; Ma, Sai
2015-12-01
The meiotic behaviour of the germ cells in 45,X/46,XY men has not been extensively studied. This study investigated the meiotic events and sperm aneuploidy in an azoospermic man with a 45,X/46,XY (50/50) mosaic karyotype to better understand the fate of the 45,X cells and the production of chromosomally abnormal spermatozoa. Combining immunofluorescence techniques and fluorescence in-situ hybridization, meiotic recombination, synapsis, meiotic sex chromosome inactivation (MSCI) and configuration were analysed, as well as sperm aneuploidy in the patient and 10 normal, fertile men. Despite the 50:50 somatic mosaicism in the patient, 25% of pachytene cells analysed were 45,X. Furthermore, 63% of pachytene cells were 46,XY with paired sex chromosomes, and 12% were 46,XY with unpaired sex chromosomes, which displayed abnormal MCSI patterns. Although the patient's testicular spermatozoa showed increased aneuploidy, the majority were of normal constitution. The X:Y sperm ratio was significantly increased compared with the controls (P XY cells in meiosis, supporting the hypothesis that stringent checkpoints ensure the favourable production of spermatozoa with normal chromosomal constitution despite an individual's abnormal karyotype. Copyright © 2015 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
Wu, Junjie; Xiong, Shuting; Jing, Jing; Chen, Xin; Wang, Weimin; Gui, Jian-Fang; Mei, Jie
2015-01-01
YY super-males have rarely been detected in nature and only been artificially created in some fish species including tilapia and yellow catfish (Pelteobagrusfulvidraco), which provides a promising model for testis development and spermatogenesis. In our previous study, significant differences in morphology and miRNA expression were detected between XY and YY testis of yellow catfish. Here, solexa sequencing technology was further performed to compare mRNA expression between XY and YY testis. Compared with unigenes expressed in XY testis, 1146 and 1235 unigenes have significantly higher and lower expression in YY testis, respectively. 605 differentially expressed unigenes were annotated to 1604 GO terms with 319 and 286 genes having relative higher expression in XY and YY testis. KEGG analysis suggested different levels of PI3K-AKT and G protein-coupled receptor (GPCR) signaling pathways between XY and YY testis. Down-regulation of miR-141/429 in YY testis was speculated to promote testis development and maturation, and several factors in PI3K-AKT and GPCR signaling pathways were found as predicted targets of miR-141/429, several of which were confirmed by dual-luciferase reporter assays. Our study provides a comparative transcriptome analysis between XY and YY testis, and reveals interactions between miRNAs and their target genes that are possibly involved in regulating testis development and spermatogenesis.
Wide spectrum of NR5A1-related phenotypes in 46,XY and 46,XX individuals.
Domenice, Sorahia; Machado, Aline Zamboni; Ferreira, Frederico Moraes; Ferraz-de-Souza, Bruno; Lerario, Antonio Marcondes; Lin, Lin; Nishi, Mirian Yumie; Gomes, Nathalia Lisboa; da Silva, Thatiana Evelin; Silva, Rosana Barbosa; Correa, Rafaela Vieira; Montenegro, Luciana Ribeiro; Narciso, Amanda; Costa, Elaine Maria Frade; Achermann, John C; Mendonca, Berenice Bilharinho
2016-12-01
Steroidogenic factor 1 (NR5A1, SF-1, Ad4BP) is a transcriptional regulator of genes involved in adrenal and gonadal development and function. Mutations in NR5A1 have been among the most frequently identified genetic causes of gonadal development disorders and are associated with a wide phenotypic spectrum. In 46,XY individuals, NR5A1-related phenotypes may range from disorders of sex development (DSD) to oligo/azoospermia, and in 46,XX individuals, from 46,XX ovotesticular and testicular DSD to primary ovarian insufficiency (POI). The most common 46,XY phenotype is atypical or female external genitalia with clitoromegaly, palpable gonads, and absence of Müllerian derivatives. Notably, an undervirilized external genitalia is frequently seen at birth, while spontaneous virilization may occur later, at puberty. In 46,XX individuals, NR5A1 mutations are a rare genetic cause of POI, manifesting as primary or secondary amenorrhea, infertility, hypoestrogenism, and elevated gonadotropin levels. Mothers and sisters of 46,XY DSD patients carrying heterozygous NR5A1 mutations may develop POI, and therefore require appropriate counseling. Moreover, the recurrent heterozygous p.Arg92Trp NR5A1 mutation is associated with variable degrees of testis development in 46,XX patients. A clear genotype-phenotype correlation is not seen in patients bearing NR5A1 mutations, suggesting that genetic modifiers, such as pathogenic variants in other testis/ovarian-determining genes, may contribute to the phenotypic expression. Here, we review the published literature on NR5A1-related disease, and discuss our findings at a single tertiary center in Brazil, including ten novel NR5A1 mutations identified in 46,XY DSD patients. The ever-expanding phenotypic range associated with NR5A1 variants in XY and XX individuals confirms its pivotal role in reproductive biology, and should alert clinicians to the possibility of NR5A1 defects in a variety of phenotypes presenting with gonadal dysfunction
dos Santos, Ana Paula; Andrade, Juliana Gabriel Ribeiro; Piveta, Cristiane Santos Cruz; de Paulo, Juliana; Guerra, Gil; de Mello, Maricilda Palandi; Maciel-Guerra, Andréa Trevas
2013-11-05
Partial and mixed gonadal dysgenesis (PGD and MGD) are characterized by genital ambiguity and the finding of either a streak gonad and a dysgenetic testis or two dysgenetic testes. The karyotype in PGD is 46,XY, whereas a 45,X/46,XY mosaicism or its variants (more than two lineages and/or structural abnormalities of the Y chromosome) is generally found in MGD. Such mosaics are also compatible with female phenotype and Turner syndrome, ovotesticular disorder of sex development, and infertility in men with normal external genitalia. During the last few years, evidences of a linkage between Y microdeletions and 45,X mosaicism have been reported. There are also indications that the instability caused by such deletions might be more significant in germ cells. The aim of this work was to investigate the presence of Y chromosome microdeletions in individuals with PGD and in those with 45,X/46,XY mosaicism or its variants and variable phenotypes. Our sample comprised 13 individuals with PGD and 15 with mosaicism, most of them with a MGD phenotype (n = 11). Thirty-six sequence tagged sites (STS) spanning the male specific region (MSY) on the Y chromosome (Yp, centromere and Yq) were analyzed by multiplex PCR and some individual reactions. All STS showed positive amplifications in the PGD group. Conversely, in the group with mosaicism, six individuals with MGD had been identified with Yq microdeletions, two of them without structural abnormalities of the Y chromosome by routine cytogenetic analysis. The deleted STSs were located within AZFb and AZFc (Azoospermia Factor) regions, which harbor several genes responsible for spermatogenesis. Absence of deletions in individuals with PGD does not confirm the hypothesis that instability of the Y chromosome in the gonads could be one of the causes of such condition. However, deletions identified in the second group indicate that mosaicism may be associated with Y chromosome abnormalities detectable only at the molecular level
Wang, Hao; Wu, Guoxing; Chen, Daojiong
2012-07-01
Based on the isotropic two spin-1/2 qubits Heisenberg model with Dzyaloshinskii-Moriya interaction in a constant external magnetic field, we have constructed the entangled quantum Otto engine. Expressions for the basic thermodynamic quantities, i.e. the amount of heat exchange, the net work output and the efficiency, are derived. The influence of thermal entanglement on these basic thermodynamic quantities is investigated. Moreover, some intriguing features and their qualitative explanations in zero and finite magnetic field are given. The validity of the second law of thermodynamics is confirmed in the system. The results obtained here have general significance and will be useful in increasing understanding of the performance of an entangled quantum engine.
Directory of Open Access Journals (Sweden)
F Keshavarz
2017-02-01
Full Text Available In this study, the effect of four-spin exchanges between the nearest and next nearest neighbor spins of honeycomb lattice on the phase diagram of S=3/2 antiferomagnetic Heisenberg model is considered with two-spin exchanges between the nearest and next nearest neighbor spins. Firstly, the method is investigated with classical phase diagram. In classical phase diagram, in addition to Neel order, classical degeneracy is also seen. The existance of this phase in diagram phase is important because of the probability of the existence of quantum spin liquid in this region for such amount of interaction. To investigate the effect of quantum fluctuation on the stability of the obtained classical phase diagram, linear spin wave theory has been used. Obtained results show that in classical degeneracy regime, the quantum fluctuations cause the order by disorder in the spin system and the ground state is ordered
Yu, Rong; Si, Qimiao
2015-09-11
Motivated by the properties of the iron chalcogenides, we study the phase diagram of a generalized Heisenberg model with frustrated bilinear-biquadratic interactions on a square lattice. We identify zero-temperature phases with antiferroquadrupolar and Ising-nematic orders. The effects of quantum fluctuations and interlayer couplings are analyzed. We propose the Ising-nematic order as underlying the structural phase transition observed in the normal state of FeSe, and discuss the role of the Goldstone modes of the antiferroquadrupolar order for the dipolar magnetic fluctuations in this system. Our results provide a considerably broadened perspective on the overall magnetic phase diagram of the iron chalcogenides and pnictides, and are amenable to tests by new experiments.
Gotlibovych, Igor; Schmidutz, Tobias F.; Gaunt, Alexander L.; Navon, Nir; Smith, Robert P.; Hadzibabic, Zoran
2014-06-01
We study the properties of an atomic Bose-Einstein condensate produced in an optical-box potential, using high-resolution Bragg spectroscopy. For a range of box sizes, up to 70μm, we directly observe Heisenberg-limited momentum uncertainty of the condensed atoms. We measure the condensate interaction energy with a precision of kB×100 pK and study, both experimentally and numerically, the dynamics of its free expansion upon release from the box potential. All our measurements are in good agreement with theoretical expectations for a perfectly homogeneous condensate of spatial extent equal to the size of the box, which also establishes the uniformity of our optical-box system on a sub-nK energy scale.
Indirect RIXS study of bimagnon excitations in triangular-lattice quantum Heisenberg antiferromagnet
Datta, Trinanjan; Luo, Cheng; Huang, Zengye; Yao, Dao-Xin
2015-03-01
Bimagnon correlations in triangular-lattice quantum Heisenberg antiferromagnet can be probed by the resonant inelastic X-ray scattering (RIXS) technique. Utilizing an interacting spin wave theory within the Bethe-Salpeter approximation scheme, we compute the K-edge indirect RIXS spectra for the nearest neighbor Heisenberg model with a general S for the entire magnetic brillouin zone. The non-collinear spin arrangement in the triangular lattice geometry supports the intrinsic spontaneous single-magnon decay or recombination. Based on our calculation, we find that the RIXS spectra display a peak at the antiferromagnetic wave vector (4 π / 3 , 0) corresponding to the triangular lattice, which is in contrast to the square lattice case. The major contribution to the RIXS spectra originates from the decay vertices arising from the three-magnon interaction terms, with the quartic interaction contributions subdued. Our results indicate that the spontaneous decay and recombination of magnons inherent to the triangular lattice model can be oberved in the RIXS spectra without a disintegration. GRU Small Grants Program, NBRPC-2012CB821400,NSFC-11275279.
Paulinelli, H. G.; de Souza, S. M.; Rojas, Onofre
2013-07-01
In this paper we explore the entanglement in an orthogonal dimer-plaquette Ising-Heisenberg chain, assembled between plaquette edges, also known as orthogonal dimer plaquettes. The quantum entanglement properties involving an infinite chain structure are quite important, not only because the mathematical calculation is cumbersome but also because real materials are well represented by infinite chains. Using the local gauge symmetry of this model, we are able to map onto a simple spin-1 like Ising and spin-1/2 Heisenberg dimer model with single effective ion anisotropy. Thereafter this model can be solved using the decoration transformation and transfer matrix approach. First, we discuss the phase diagram at zero temperature of this model, where we find five ground states, one ferromagnetic, one antiferromagnetic, one triplet-triplet disordered and one triplet-singlet disordered phase, beside a dimer ferromagnetic-antiferromagnetic phase. In addition, we discuss the thermodynamic properties such as entropy, where we display the residual entropy. Furthermore, using the nearest site correlation function it is possible also to analyze the pairwise thermal entanglement for both orthogonal dimers. Additionally, we discuss the threshold temperature of the entangled region as a function of Hamiltonian parameters. We find a quite interesting thin reentrance threshold temperature for one of the dimers, and we also discuss the differences and similarities for both dimers.
Stapp`s quantum dualism: The James/Heisenberg model of consciousness
Energy Technology Data Exchange (ETDEWEB)
Noyes, H.P.
1994-02-18
Henry Stapp attempts to resolve the Cartesian dilemma by introducing what the author would characterize as an ontological dualism between mind and matter. His model for mind comes from William James` description of conscious events and for matter from Werner Heisenberg`s ontological model for quantum events (wave function collapse). His demonstration of the isomorphism between the two types of events is successful, but in the author`s opinion fails to establish a monistic, scientific theory. The author traces Stapp`s failure to his adamant rejection of arbitrariness, or `randomness`. This makes it impossible for him (or for Bohr and Pauli before him) to understand the power of Darwin`s explanation of biology, let along the triumphs of modern `neo-Darwinism`. The author notes that the point at issue is a modern version of the unresolved opposition between Leucippus and Democritus on one side and Epicurus on the other. Stapp`s views are contrasted with recent discussions of consciousness by two eminent biologists: Crick and Edelman. They locate the problem firmly in the context of natural selection on the surface of the earth. Their approaches provide a sound basis for further scientific work. The author briefly examines the connection between this scientific (rather than ontological) framework and the new fundamental theory based on bit-strings and the combinatorial hierarchy.
Conditions for the appearance of boundary modes in topological phases of Heisenberg spin ladders
Robinson, Neil; Atland, Alexander; Egger, Reinhold; Gergs, Nkilas; Konik, Robert; Li, Wei; Schuricht, Dirk; Tsvelik, Alexei; Weichselbaum, Andreas
We consider the problem of delineating the necessary conditions for the appearance of boundary modes in extended SU (2) Heisenberg spin ladders. Specifically, we study Heisenberg ladders with rung exchange, J⊥, and ring exchange, JX, that admit a field theoretic description in terms of Majorana fermions in the continuum limit. In this description there are four Majorana fermions, arranged in a triplet and a singlet. This suggests there are four distinct phases, corresponding to the configurations of the signs of the triplet mt and singlet ms masses. We label these phases as: Haldane (mt > 0 ,ms 0), VBS+ (mt ,ms > 0) and VBS- (mt ,ms VBS+ phase, where all the Majorana fermions have gapless boundary modes. The absence of a gapless boundary mode in the rung singlet phase is surprising; we find that the singlet mode can become gapless if open boundary conditions are replaced with a continuous change in lattice parameters. We suggest a symmetry-allowed modification to the low-energy effective theory which may be responsible for this behavior.
Verifying Heisenberg's error-disturbance relation using a single trapped ion.
Zhou, Fei; Yan, Leilei; Gong, Shijie; Ma, Zhihao; He, Jiuzhou; Xiong, Taiping; Chen, Liang; Yang, Wanli; Feng, Mang; Vedral, Vlatko
2016-10-01
Heisenberg's uncertainty relations have played an essential role in quantum physics since its very beginning. The uncertainty relations in the modern quantum formalism have become a fundamental limitation on the joint measurements of general quantum mechanical observables, going much beyond the original discussion of the trade-off between knowing a particle's position and momentum. Recently, the uncertainty relations have generated a considerable amount of lively debate as a result of the new inequalities proposed as extensions of the original uncertainty relations. We report an experimental test of one of the new Heisenberg's uncertainty relations using a single 40 Ca + ion trapped in a harmonic potential. By performing unitary operations under carrier transitions, we verify the uncertainty relation proposed by Busch, Lahti, and Werner (BLW) based on a general error-trade-off relation for joint measurements on two compatible observables. The positive operator-valued measure, required by the compatible observables, is constructed by single-qubit operations, and the lower bound of the uncertainty, as observed, is satisfied in a state-independent manner. Our results provide the first evidence confirming the BLW-formulated uncertainty at a single-spin level and will stimulate broad interests in various fields associated with quantum mechanics.
Fischer, Andreas
2016-11-01
Optical flow velocity measurements are important for understanding the complex behavior of flows. Although a huge variety of methods exist, they are either based on a Doppler or a time-of-flight measurement principle. Doppler velocimetry evaluates the velocity-dependent frequency shift of light scattered at a moving particle, whereas time-of-flight velocimetry evaluates the traveled distance of a scattering particle per time interval. Regarding the aim of achieving a minimal measurement uncertainty, it is unclear if one principle allows to achieve lower uncertainties or if both principles can achieve equal uncertainties. For this reason, the natural, fundamental uncertainty limit according to Heisenberg's uncertainty principle is derived for Doppler and time-of-flight measurement principles, respectively. The obtained limits of the velocity uncertainty are qualitatively identical showing, e.g., a direct proportionality for the absolute value of the velocity to the power of 32 and an indirect proportionality to the square root of the scattered light power. Hence, both measurement principles have identical potentials regarding the fundamental uncertainty limit due to the quantum mechanical behavior of photons. This fundamental limit can be attained (at least asymptotically) in reality either with Doppler or time-of-flight methods, because the respective Cramér-Rao bounds for dominating photon shot noise, which is modeled as white Poissonian noise, are identical with the conclusions from Heisenberg's uncertainty principle.
When Bertolt Brecht looked into Heisenberg´s microscope
CERN. Geneva; Peter, Andrej; Ernst, Karin; Arnold, Lukas
2013-01-01
The meeting will be hosted in Vidyo (http://information-technology.web.cern.ch/services/fe/vidyo) In order to connect from your PC firstcheck if your requirements are o.k. http://stage.xcarab.com/vidyo/syscheck/ . You need a microphone to be connected at least to hear the speaker. To connect If you want to connect to the system using your CERN account you should register to the Vidyo service (http://information-technology.web.cern.ch/services/fe/vidyo/howto/users-register-vidyo-service). Go to the Join Now! link below and click on it. You will be directed to the Vydio Portal. You can login as a "guest" or you can use your CERN account. If you login as a "guest" you will only need to enteer a random Guest Name and click on Join. If you want to login with your CERN user account, put in your regeistered account (username and password are the same of your standard CERN account) You will be proposed to to download and install the Vid...
Raedt, B. De; Raedt, H. De; Fivez, J.
1981-01-01
Is is found that nonlinear effects give rise to anomalies in the spectrum of the antiferromagnetic Heisenberg chain in an external field, even at low temperatures. Divergences in the two-magnon density of states are responsible for additional resonances, besides the usual spin-wave peak, in the
SMAD2 and p38 signaling pathways act in concert to determine XY primordial germ cell fate in mice.
Wu, Quan; Fukuda, Kurumi; Weinstein, Michael; Graff, Jonathan M; Saga, Yumiko
2015-02-01
The sex of primordial germ cells (PGCs) is determined in developing gonads on the basis of cues from somatic cells. In XY gonads, sex-determining region Y (SRY) triggers fibroblast growth factor 9 (FGF9) expression in somatic cells. FGF signaling, together with downstream nodal/activin signaling, promotes male differentiation in XY germ cells by suppressing retinoic acid (RA)-dependent meiotic entry and inducing male-specific genes. However, the mechanism by which nodal/activin signaling regulates XY PGC fate is unknown. We uncovered the roles of SMAD2/3 and p38 MAPK, the putative downstream factors of nodal/activin signaling, in PGC sexual fate decision. We found that conditional deletion of Smad2, but not Smad3, from XY PGCs led to a loss of male-specific gene expression. Moreover, suppression of RA signaling did not rescue male-specific gene expression in Smad2-mutant testes, indicating that SMAD2 signaling promotes male differentiation in a RA-independent manner. By contrast, we found that p38 signaling has an important role in the suppression of RA signaling. The Smad2 deletion did not disrupt the p38 signaling pathway even though Nodal expression was significantly reduced, suggesting that p38 was not regulated by nodal signaling in XY PGCs. Additionally, the inhibition of p38 signaling in the Smad2-mutant testes severely impeded XY PGC differentiation and induced meiosis. In conclusion, we propose a model in which p38 and SMAD2 signaling coordinate to determine the sexual fate of XY PGCs. © 2015. Published by The Company of Biologists Ltd.
Strečka, Jozef; Rojas, Onofre; Verkholyak, Taras; Lyra, Marcelo L
2014-02-01
The frustrated spin-1/2 Ising-Heisenberg ladder with Heisenberg intra-rung and Ising inter-rung interactions is exactly solved in a longitudinal magnetic field by taking advantage of the local conservation of the total spin on each rung and the transfer-matrix method. We have rigorously calculated the ground-state phase diagram, magnetization process, magnetocaloric effect, and basic thermodynamic quantities for the model, which can be alternatively viewed as an Ising-Heisenberg tetrahedral chain. It is demonstrated that a stepwise magnetization curve with an intermediate plateau at half of the saturation magnetization is also reflected in respective stepwise changes of the concurrence serving as a measure of bipartite entanglement. The ground-state phase diagram and zero-temperature magnetization curves of the Ising-Heisenberg tetrahedral chain are contrasted with the analogous results of the purely quantum Heisenberg tetrahedral chain, which have been obtained through density-matrix renormalization group (DMRG) calculations. While both ground-state phase diagrams fully coincide in the regime of weak inter-rung interaction, the purely quantum Heisenberg tetrahedral chain develops Luttinger spin-liquid and Haldane phases for strongly coupled rungs, which are absent in the Ising-Heisenberg counterpart model.
Liu, Chia-Chuan; Goswami, Pallab; Si, Qimiao
2017-09-01
Due to the interaction between the topological defects of an order parameter and underlying fermions, the defects can possess induced fermion numbers, leading to several exotic phenomena of fundamental importance to both condensed matter and high-energy physics. One of the intriguing outcomes of induced fermion numbers is the presence of fluctuating competing orders inside the core of a topological defect. In this regard, the interaction between fermions and skyrmion excitations of an antiferromagnetic phase can have important consequences for understanding the global phase diagrams of many condensed matter systems where antiferromagnetism and several singlet orders compete. We critically investigate the relation between fluctuating competing orders and skyrmion excitations of the antiferromagnetic insulating phase of a half-filled Kondo-Heisenberg model on a honeycomb lattice. By combining analytical and numerical methods, we obtain the exact eigenstates of underlying Dirac fermions in the presence of a single skyrmion configuration, which are used for computing the induced chiral charge. Additionally, by employing this nonperturbative eigenbasis, we calculate the susceptibilities of different translational symmetry breaking charges, bond and current density wave orders, and translational symmetry preserving Kondo singlet formations. Based on the computed susceptibilities, we establish spin Peierls and Kondo singlets as dominant competing orders of antiferromagnetism. We show favorable agreement between our findings and field theoretic predictions based on the perturbative gradient expansion scheme, which crucially relies on the adiabatic principle and plane-wave eigenstates for Dirac fermions. The methodology developed here can be applied to many other correlated systems supporting competition between spin-triplet and spin-singlet orders in both lower and higher spatial dimensions.
1971-01-01
Remote from the noise and bustle of Europe's capital cities, in the charming German lake-side town of Lindau, close to the borders of Austria and Switzerland, Nobel Prize Winners in physics gathered together from June 28-July 2 to talk of their science and its interaction with society.
DEFF Research Database (Denmark)
Bhaskar, Mahajan Sagar; Padmanaban, Sanjeevikumar; Maroti, Pandav Kiran
2017-01-01
applications. The noticeable features of the proposed 2LC-Y converter topologies are: i) Only one power control switch and input source; ii) High negative output voltage with moderate duty ratio; iii) Low output current and minimal internal resistance; iv) Transformer-less converter topologies; v) High voltage......New members of XY converter family topologies are proposed in this treatise for a high-voltage/low-current renewable application. Based on the X Converter, the whole existing X-Y Converter family is categorized into four categories; L-Y, 2L-Y, 2LC-Y and 2LCm-Y converter. Four new 2LC-Y topologies...... (2LC-LVD, 2LC-2LVD, 2LC-2LCVD and 2LC-2LCmVD) converters are presented in this treatise which offer an effective solution for renewable applications requiring a very high voltage conversion ratio such as a Photovoltaic Multilevel Inverter (PV-MLI) system, hybrid electrical drives and automotive...
Can the external masculinization score predict the success of genetic testing in 46,XY DSD?
Directory of Open Access Journals (Sweden)
Ruthie Su
2015-05-01
Full Text Available Genetic testing is judiciously applied to individuals with Disorders of Sex Development (DSD and so it is necessary to identify those most likely to benefit from such testing. We hypothesized that the external masculinization score (EMS is inversely associated with the likelihood of finding a pathogenic genetic variant. Patients with 46,XY DSD from a single institution evaluated from 1994-2014 were included. Results of advanced cytogenetic and gene sequencing tests were recorded. An EMS score (range 0-12 was assigned to each patient according to the team's initial external genitalia physical examination. During 1994-2011, 44 (40% patients with 46,XY DSD were evaluated and underwent genetic testing beyond initial karyotype; 23% (10/44 had a genetic diagnosis made by gene sequencing or array. The median EMS score of those with an identified pathogenic variant was significantly different from those in whom no confirmed genetic cause was identified [median 3 (95% CI, 2-6 versus 6 (95% CI, 5-7, respectively (p = 0.02], but limited to diagnoses of complete or partial androgen insensitivity (8/10 or 5-reductase deficiency (2/10. In the modern cohort (2012-2014, the difference in median EMS in whom a genetic cause was or was not identified approached significance (p = 0.05, median 3 (95% CI, 0-7 versus 7 (95% CI, 6-9, respectively. When all patients from 1994-2014 are pooled, the EMS is significantly different amongst those with compared to those without a genetic cause (median EMS 3 vs. 6, p < 0.02. We conclude that an EMS of 3 or less may indicate a higher likelihood of identifying a genetic cause of 46,XY DSD and justify genetic screening, especially when androgen insensitivity is suspected.
Potential energy landscapes for the 2D XY model: Minima, transition states, and pathways
Mehta, Dhagash; Hughes, Ciaran; Schröck, Mario; Wales, David J.
2013-11-01
We describe a numerical study of the potential energy landscape for the two-dimensional XY model (with no disorder), considering up to 100 spins and central processing unit and graphics processing unit implementations of local optimization, focusing on minima and saddles of index one (transition states). We examine both periodic and anti-periodic boundary conditions, and show that the number of stationary points located increases exponentially with increasing lattice size. The corresponding disconnectivity graphs exhibit funneled landscapes; the global minima are readily located because they exhibit relatively large basins of attraction compared to the higher energy minima as the lattice size increases.
Anisotropy in the helicity modulus of a three-dimensional XY-model: application to YBCO
Energy Technology Data Exchange (ETDEWEB)
Mitrovic, Bozidar; Bose, Shyamal K; Samokhin, Kirill [Physics Department, Brock University, St Catharines, ON L2S 3A1 (Canada)
2003-04-09
We present a Monte Carlo study of the helicity moduli of an anisotropic classical three-dimensional XY-model of YBCO in the superconducting state. It is found that both the ab-plane and the c-axis helicity moduli, which are proportional to the inverse square of the corresponding magnetic field penetration depth, vary linearly with temperature at low temperatures. The result for the c-axis helicity modulus is in disagreement with the experiments on high-quality samples of YBCO. Thus we conclude that purely classical phase fluctuations of the superconducting order parameter cannot account for the observed c-axis electrodynamics of YBCO.
Sexual quality of life of individuals with 46,XY disorders of sex development.
Schönbucher, Verena; Schweizer, Katinka; Rustige, Lisa; Schützmann, Karsten; Brunner, Franziska; Richter-Appelt, Hertha
2012-12-01
There has recently been a growing acceptance that it is not only heterosexual functioning of surgically adjusted genitalia which should be considered when measuring the treatment outcome of persons with disorders of sex development (DSD) but also their overall sexual quality of life (SexQoL). A comprehensive cross-sectional investigation of SexQoL of persons with 46,XY DSD. Forty-seven persons with 46,XY DSD (age 17-60 years) were examined by means of a questionnaire on various aspects of SexQoL. Scores were compared to a nonclinical convenience sample consisting of 145 women. Data were analyzed separately for diagnostic subgroups. Furthermore, persons whose external genitalia had been surgically corrected were compared with persons whose genitalia had been left unaltered. The Multidimensional Scale of Sexuality, the German Questionnaire on Feelings of Inadequacy in Social and Sexual Situations (FUSS), items on sexual dysfunctions according to DSM-IV-TR and self-constructed measures on sexual-activity history (e.g., previous sexual experience), sexual anxieties, and satisfaction with overall sex life and sexual function comprised the standardized assessment instruments. Compared with the nonclinical group, persons with 46,XY DSD had more often no partner (P = 0.056), felt more insecure in social (Mdn(DSD) = 17.0, Mdn(comparison) = 12.0, P = 0.001) and sexual situations (Mdn(DSD) = 17.0, Mdn(comparison) = 11.0, P = 0.006), had more sexual problems (Mdn(DSD) = 4.0, Mdn(comparison) = 3.0, P = 0.001), and were less satisfied with overall sex life (Mdn(DSD) = 3.0, Mdn(comparison) = 4.0, P = 0.000) and sexual function (Mdn(DSD) = 4.0, Mdn(comparison) = 4.0, P = 0.000). Results were inconsistent with regard to sexual-activity history (e.g., previous sexual experience). Participants who underwent genital surgery showed less dyspareunia (P = 0.027) but more fear of injuries during intercourse (P = 0.019) than those whose genitals were left unaltered. SexQoL of persons with
Evidence to exclude SOX9 as a candidate gene for XY sex reversal without skeletal malformation.
Kwok, C; Goodfellow, P N; Hawkins, J R
1996-01-01
The skeletal malformation syndrome campomelic dysplasia (CMD1) is caused by mutations within the SOX9 gene or chromosomal rearrangement breakpoints outside SOX9. Approximately three quarters of cases of CMD1 in XY subjects show complete or partial sex reversal. As some mutations cause CMD1 alone and others cause CMD1 and sex reversal, it is conceivable that some mutations might cause sex reversal in the absence of CMD1. In this study, we have investigated this possibility by screening the ent...
Critical behaviour of the 3D XY-model a Monte Carlo study
Gottlob, Aloysius P.
1993-01-01
We present the results of a study of the three-dimensional $XY$-model on a simple cubic lattice using the single cluster updating algorithm combined with improved estimators. We have measured the susceptibility and the correlation length for various couplings in the high temperature phase on lattices of size up to $L=112$. At the transition temperature we studied the fourth-order cumulant and other cumulant-like quantities on lattices of size up to $L=64$. From our numerical data we obtain for the critical coupling $\\coup_c=0.45420(2)$, and for the static critical exponents $\\gamma /\
Identification of X Monosomy Cells From a Gonad of Mixed Gonadal Dysgenesis With a 46,XY Karyotype
Nishina-Uchida, Noriko; Fukuzawa, Ryuji; Hasegawa, Yukihiro; Morison, Ian M.
2015-01-01
Abstract Mixed gonadal dysgenesis (MGD) is a disorder of sexual development that typically has a mosaic 45,X/46,XY karyotype. A 1-year-old infant with 46,XY identified by peripheral blood karyotype demonstrated clinical manifestations and gonadal pathologic features of MGD. Fluorescence in situ hybridization (FISH) for X and Y chromosomes and immunofluorescence for SRY along with testicular and ovarian lineage markers SOX9 and FOXL2, respectively, were performed on paraffin sections from the gonad to ascertain the somatic mosaic state for 45,X monosomy and 46,XY cells. The gonad consisted of cells with X and XY signals, which were further quantified in comparison with a normal control testis by a digital image analysis program. The average percentages of 45,X cells of this patient's gonad and a control testis were 39.0% and 5.7%, respectively (χ2 test, P < 0.001). SRY expression was absent in approximately 10% of precursor granulosa cells (FOXL2 positive) and precursor Sertoli/granulosa cells (both SOX9 and FOXL2 positive) within gonadoblastomas, confirming the involvement of 45,X cells. A combination of analysis of FISH and immunofluorescence for SRY in the gonadal tissue could identify 45,X cells in MGD with 46,XY. PMID:25860218
Nishina-Uchida, Noriko; Fukuzawa, Ryuji; Hasegawa, Yukihiro; Morison, Ian M
2015-04-01
Mixed gonadal dysgenesis (MGD) is a disorder of sexual development that typically has a mosaic 45,X/46,XY karyotype. A 1-year-old infant with 46,XY identified by peripheral blood karyotype demonstrated clinical manifestations and gonadal pathologic features of MGD. Fluorescence in situ hybridization (FISH) for X and Y chromosomes and immunofluorescence for SRY along with testicular and ovarian lineage markers SOX9 and FOXL2, respectively, were performed on paraffin sections from the gonad to ascertain the somatic mosaic state for 45,X monosomy and 46,XY cells. The gonad consisted of cells with X and XY signals, which were further quantified in comparison with a normal control testis by a digital image analysis program. The average percentages of 45,X cells of this patient's gonad and a control testis were 39.0% and 5.7%, respectively (χ2 test, P < 0.001). SRY expression was absent in approximately 10% of precursor granulosa cells (FOXL2 positive) and precursor Sertoli/granulosa cells (both SOX9 and FOXL2 positive) within gonadoblastomas, confirming the involvement of 45,X cells. A combination of analysis of FISH and immunofluorescence for SRY in the gonadal tissue could identify 45,X cells in MGD with 46,XY.
Generalized Heisenberg-Euler formula in Abelian gauge theory with parity violation
Yamashita, Kimiko; Fan, Xing; Kamioka, Shusei; Asai, Shoji; Sugamoto, Akio
2017-12-01
A generalized Heisenberg-Euler formula is given for an Abelian gauge theory having vector as well as axial vector couplings to a massive fermion. So, the formula is applicable to a parity-violating theory. The gauge group is chosen to be U(1). The formula is quite similar to that in quantum electrodynamics, but there is a complexity in which one factor (related to spin) is expressed in terms of the expectation value. The expectation value is evaluated by the contraction with the one-dimensional propagator in a given background field. The formula affords a basis to the vacuum magnetic birefringence experiment, which aims to probe the dark sector, where the interactions of the light fermions with the gauge fields are not necessarily parity conserving.
arXiv Topology in the 2d Heisenberg Model under Gradient Flow
Sandoval, Ilya O.; de Forcrand, Philippe; Gerber, Urs; Mejía-Díaz, Héctor
2017-10-28
The 2d Heisenberg model — or 2d O(3) model — is popular in condensed matter physics, and in particle physics as a toy model for QCD. Along with other analogies, it shares with 4d Yang-Mills theories, and with QCD, the property that the configurations are divided in topological sectors. In the lattice regularisation the topological charge Q can still be defined such that $Q\\in \\mathbb{Z}$. It has generally been observed, however, that the topological susceptibility ${{\\chi }_{t}}=\\langle {{Q}^{2}}\\rangle /V$ does not scale properly in the continuum limit, i.e. that the quantity ${{\\chi }_{t}}{{\\xi }^{2}}$ diverges for ξ → ∞ (where ξ is the correlation length in lattice units). Here we address the question whether or not this divergence persists after the application of the Gradient Flow.
Optimal Control for Fast and Robust Generation of Entangled States in Anisotropic Heisenberg Chains
Zhang, Xiong-Peng; Shao, Bin; Zou, Jian
2017-05-01
Motivated by some recent results of the optimal control (OC) theory, we study anisotropic XXZ Heisenberg spin-1/2 chains with control fields acting on a single spin, with the aim of exploring how maximally entangled state can be prepared. To achieve the goal, we use a numerical optimization algorithm (e.g., the Krotov algorithm, which was shown to be capable of reaching the quantum speed limit) to search an optimal set of control parameters, and then obtain OC pulses corresponding to the target fidelity. We find that the minimum time for implementing our target state depending on the anisotropy parameter Δ of the model. Finally, we analyze the robustness of the obtained results for the optimal fidelities and the effectiveness of the Krotov method under some realistic conditions.
Quantum discord in spin-1/2 Heisenberg chains with Dzyaloshinkii-Moriya interaction
Ma, Xiao San; Wang, An Min
2015-12-01
We have investigated the quantum discord (QD) of the thermal density matrix of spin-1/2 Heisenberg chains with Dzyaloshinskii-Moriya (DM) interaction. With fermionization technique, we study the mutual effect of DM interaction and the external magnetic field on the QD and the entanglement. Our analysis implies that the DM interaction can enhance the QD while the external magnetic field will shrink the QD. By a comparison between the entanglement and the QD, we find that the QD is more robust to the temperature and to the external magnetic field than the entanglement of formation (EoF) in the sense that the EoF takes a zero value while the QD does not for high temperature and strong external magnetic field. This point confirms the conclusion that there exist some separable states containing non-zero QD.
Dynamics of the spin-1/2 Heisenberg chain initialized in a domain-wall state
Misguich, Grégoire; Mallick, Kirone; Krapivsky, P. L.
2017-11-01
We study the dynamics of an isotropic spin-1/2 Heisenberg chain starting in a domain-wall initial condition where the spins are initially up on the left half-line and down on the right half-line. We focus on the long-time behavior of the magnetization profile. We perform extensive time-dependent density-matrix renormalization-group simulations (up to t =350 ) and find that the data are compatible with a diffusive behavior. Subleading corrections decay slowly blurring the emergence of the diffusive behavior. We also compare our results with two alternative scenarios: superdiffusive behavior and enhanced diffusion with a logarithmic correction. We finally discuss the evolution of the entanglement entropy.
Powell, B. J.; Merino, J.; Khosla, A. L.; Jacko, A. C.
2017-03-01
Motivated by recent synthetic and theoretical progress we consider magnetism in crystals of multinuclear organometallic complexes. We calculate the Heisenberg symmetric exchange and the Dzyaloshinskii-Moriya antisymmetric exchange. We show how, in the absence of spin-orbit coupling, the interplay of electronic correlations and quantum interference leads to a quasi-one-dimensional effective spin model in a typical trinuclear complex, Mo3S7 (dmit)3, despite its underlying three-dimensional band structure. We show that both intra- and intermolecular spin-orbit coupling can cause an effective Dzyaloshinskii-Moriya interaction. Furthermore, we show that even for an isolated pair of molecules the relative orientation of the molecules controls the nature of the Dzyaloshinskii-Moriya coupling. We show that interference effects also play a crucial role in determining the Dzyaloshinskii-Moriya interaction. Thus, we argue that multinuclear organometallic complexes represent an ideal platform to investigate the effects of Dzyaloshinskii-Moriya interactions on quantum magnets.
Directory of Open Access Journals (Sweden)
Mihai V. Putz
2010-10-01
Full Text Available Within the path integral Feynman formulation of quantum mechanics, the fundamental Heisenberg Uncertainty Relationship (HUR is analyzed in terms of the quantum fluctuation influence on coordinate and momentum estimations. While introducing specific particle and wave representations, as well as their ratio, in quantifying the wave-to-particle quantum information, the basic HUR is recovered in a close analytical manner for a large range of observable particle-wave Copenhagen duality, although with the dominant wave manifestation, while registering its progressive modification with the factor √1-n2, in terms of magnitude n ε [0,1] of the quantum fluctuation, for the free quantum evolution around the exact wave-particle equivalence. The practical implications of the present particle-to-wave ratio as well as of the free-evolution quantum picture are discussed for experimental implementation, broken symmetry and the electronic localization function.
The Hypermultiplet with Heisenberg Isometry in N=2 Global and Local Supersymmetry
Ambrosetti, Nicola; Derendinger, Jean-Pierre; Tziveloglou, Panteleimon
2011-01-01
The string coupling of N=2 supersymmetric compactifications of type II string theory on a Calabi-Yau manifold belongs to the so-called universal dilaton hypermultiplet, that has four real scalars living on a quaternion-Kaehler manifold. Requiring Heisenberg symmetry, which is a maximal subgroup of perturbative isometries, reduces the possible manifolds to a one-parameter family that describes the tree-level effective action deformed by the only possible perturbative correction arising at one-loop level. A similar argument can be made at the level of global supersymmetry where the scalar manifold is hyper-Kaehler. In this work, the connection between global and local supersymmetry is explicitly constructed, providing a non-trivial gravity decoupled limit of type II strings already in perturbation theory.
Solving the {eta}-problem in hybrid inflation with Heisenberg symmetry and stabilized modulus
Energy Technology Data Exchange (ETDEWEB)
Antusch, Stefan; Dutta, Koushik; Kostka, Philipp M. [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Muenchen (Germany); Bastero-Gil, Mar [Departamento de Fisica Teorica y del Cosmos and Centro Andaluz de Fisica de Particulas Elementales, Universidad de Granada, 19071 Granada (Spain); King, Steve F., E-mail: antusch@mppmu.mpg.de, E-mail: mbg@ugr.es, E-mail: koushik@mppmu.mpg.de, E-mail: sfk@hep.phys.soton.ac.uk, E-mail: kostka@mppmu.mpg.de [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom)
2009-01-15
We propose a class of models in which the {eta}-problem of supersymmetric hybrid inflation is resolved using a Heisenberg symmetry, where the associated modulus field is stabilized and made heavy with the help of the large vacuum energy during inflation without any fine-tuning. The proposed class of models is well motivated both from string theory considerations, since it includes the commonly encountered case of no-scale supergravity Kaehler potential, and from the perspective of particle physics since a natural candidate for the inflaton in this class of models is the right-handed sneutrino which is massless during the inflationary epoch, and subsequently acquires a large mass at the end of inflation. We study a specific example motivated by sneutrino hybrid inflation with no-scale supergravity in some detail, and show that the spectral index may lie within the latest WMAP range, while the tensor-to-scalar ratio is very small.
Kish, S. P.; Ralph, T. C.
2017-10-01
We study the problem of estimating the phase shift due to the general relativistic time dilation in the interference of photons using a nonlinear Mach-Zender interferometer setup. By introducing two nonlinear Kerr materials, one in the bottom and one in the top arm, we can measure the nonlinear phase ϕNL produced by the space-time curvature and achieve a scaling of the standard deviation with photon number (N ) of 1 /Nβ where β >1 , which exceeds the conventional Heisenberg limit of a linear interferometer (1 /N ). The nonlinear phase shift is an effect that is amplified by the intensity of the probe field. In a regime of high photon number, this effect can dominate over the linear phase shift.
Exploring entropic uncertainty relation in the Heisenberg XX model with inhomogeneous magnetic field
Huang, Ai-Jun; Wang, Dong; Wang, Jia-Ming; Shi, Jia-Dong; Sun, Wen-Yang; Ye, Liu
2017-08-01
In this work, we investigate the quantum-memory-assisted entropic uncertainty relation in a two-qubit Heisenberg XX model with inhomogeneous magnetic field. It has been found that larger coupling strength J between the two spin-chain qubits can effectively reduce the entropic uncertainty. Besides, we observe the mechanics of how the inhomogeneous field influences the uncertainty, and find out that when the inhomogeneous field parameter b1. Intriguingly, the entropic uncertainty can shrink to zero when the coupling coefficients are relatively large, while the entropic uncertainty only reduces to 1 with the increase of the homogeneous magnetic field. Additionally, we observe the purity of the state and Bell non-locality and obtain that the entropic uncertainty is anticorrelated with both the purity and Bell non-locality of the evolution state.
The hypermultiplet with Heisenberg isometry in N = 2 global and local supersymmetry
Ambrosetti, Nicola; Antoniadis, Ignatios; Derendinger, Jean-Pierre; Tziveloglou, Pantelis
2011-06-01
The string coupling of N = 2 supersymmetric compactifications of type II string theory on a Calabi-Yau manifold belongs to the so-called universal dilaton hyper-multiplet, that has four real scalars living on a quaternion-Kähler manifold. Requiring Heisenberg symmetry, which is a maximal subgroup of perturbative isometries, reduces the possible manifolds to a one-parameter family that describes the tree-level effective action deformed by the only possible perturbative correction arising at one-loop level. A similar argument can be made at the level of global supersymmetry where the scalar manifold is hyper-Kähler. In this work, the connection between global and local supersymmetry is explicitly constructed, providing a non-trivial gravity decoupled limit of type II strings already in perturbation theory.
Classical ground states of Heisenberg and X Y antiferromagnets on the windmill lattice
Jeevanesan, Bhilahari; Orth, Peter P.
2014-10-01
We investigate the classical Heisenberg and planar (X Y ) spin models on the windmill lattice. The windmill lattice is formed out of two widely occurring lattice geometries: a triangular lattice is coupled to its dual honeycomb lattice. Using a combination of iterative minimization, heat-bath Monte Carlo simulations, and analytical calculations, we determine the complete ground-state phase diagram of both models and find the exact energies of the phases. The phase diagram shows a rich phenomenology due to competing interactions and hosts, in addition to collinear and various coplanar phases, also intricate noncoplanar phases. We briefly outline different paths to an experimental realization of these spin models. Our extensive study provides a starting point for the investigation of quantum and thermal fluctuation effects.
Modified Spin-Wave Theory on Low-Dimensional Heisenberg Ferrimagnets: A New Robust Formulation
Noriki, Yusaku; Yamamoto, Shoji
2017-03-01
We propose a new scheme for modifying conventional spin waves so as to precisely describe low-dimensional Heisenberg ferrimagnets at finite temperatures. What is called the modified spin-wave theory was initiated by Takahashi, who intended to calculate the low-temperature thermodynamics of low-dimensional Heisenberg ferromagnets, where Holstein-Primakoff bosons are constrained to keep the total uniform magnetization zero in a straightforward manner. If the concept of an ideal Bose gas with a fixed density is applied to antiferromagnets and ferrimagnets, the formulation is no longer trivial, having rich variety in the way how the conventional spin waves, especially those in ferrimagnets, are constrained and brought into interaction. Which magnetization should be kept zero, uniform, staggered, or both? One or more chemical potentials can be introduced so as to satisfy the relevant constraint condition either in diagonalizing the Hamiltonian or in minimizing the free energy, making the Bogoliubov transformation dependent on temperature or leaving it free from temperature dependence. We can bring the thus-modified spin waves into interaction on the basis of the Hartree-Fock approximation or through the use of Wick's theorem in an attempt to refine their descriptions. Comparing various modification schemes both numerically and analytically in one and two dimensions, we eventually find an excellent bosonic language capable of describing heterogeneous quantum magnets on a variety of lattices over the whole temperature range — Wick's-theorem-based interacting spin waves modified so as to keep every sublattice magnetization zero via the temperature-dependent Bogoliubov transformation.
Large-scale calculation of ferromagnetic spin systems on the pyrochlore lattice
Energy Technology Data Exchange (ETDEWEB)
Soldatov, Konstantin, E-mail: soldatov_ks@students.dvfu.ru [School of Natural Sciences, Far Eastern Federal University, Vladivostok (Russian Federation); Nefedev, Konstantin, E-mail: nefedev.kv@dvfu.ru [School of Natural Sciences, Far Eastern Federal University, Vladivostok (Russian Federation); Institute of Applied Mathematics, Far Eastern Branch, Russian Academy of Science, Vladivostok (Russian Federation); Komura, Yukihiro [CIJ-solutions, Chuo-ku, Tokyo 103-0023 (Japan); Okabe, Yutaka, E-mail: okabe@phys.se.tmu.ac.jp [Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397 (Japan)
2017-02-19
We perform the high-performance computation of the ferromagnetic Ising model on the pyrochlore lattice. We determine the critical temperature accurately based on the finite-size scaling of the Binder ratio. Comparing with the data on the simple cubic lattice, we argue the universal finite-size scaling. We also calculate the classical XY model and the classical Heisenberg model on the pyrochlore lattice. - Highlights: • Calculations of the ferromagnetic models on the pyrochlore lattice were performed. • Precise critical temperatures were determined using Binder ratio finite-size scaling. • The universal finite-size scaling was argued.
Gender identity and gender of rearing in 46 XY disorders of sexual development
Directory of Open Access Journals (Sweden)
Arushi Gangaher
2016-01-01
Full Text Available Background: Disorders of sexual development (DSD may pose a challenge to live as a fully-functioning male or female. In this study, we prospectively assessed eleven 46 XY DSD patients who were being treated at our center over the last 8 months for gender dysphoria. Materials and Methods: To determine gender dysphoria, age-appropriate gender identity (GI questionnaires were used. For patients, 12 years and below, parent report GI questionnaire for children was used and for those above 12 years of age, GI/gender dysphoria questionnaire for adolescents and adults was administered. Results: Of 11 patients with 46 XY DSD, three were diagnosed with 5 alpha reductase deficiency (5aRD, two with partial gonadal dysgenesis, three with partial androgen insensitivity syndrome, one each with ovotesticular, complete gonadal dysgenesis, and complete androgen insensitivity. Gender assigned at birth was female in eight and male in three patients. Among the eight reared as female, gender had been reassigned as male in three patients well before the present study was conducted. None of the eleven patients had gender dysphoria at the time of this study. Conclusion: Early gender of rearing was seen to be a critical indicator of present GI in our patients except in cases of 5aRD.
Gender identity and gender of rearing in 46 XY disorders of sexual development.
Gangaher, Arushi; Chauhan, Vasundhera; Jyotsna, Viveka P; Mehta, Manju
2016-01-01
Disorders of sexual development (DSD) may pose a challenge to live as a fully-functioning male or female. In this study, we prospectively assessed eleven 46 XY DSD patients who were being treated at our center over the last 8 months for gender dysphoria. To determine gender dysphoria, age-appropriate gender identity (GI) questionnaires were used. For patients, 12 years and below, parent report GI questionnaire for children was used and for those above 12 years of age, GI/gender dysphoria questionnaire for adolescents and adults was administered. Of 11 patients with 46 XY DSD, three were diagnosed with 5 alpha reductase deficiency (5aRD), two with partial gonadal dysgenesis, three with partial androgen insensitivity syndrome, one each with ovotesticular, complete gonadal dysgenesis, and complete androgen insensitivity. Gender assigned at birth was female in eight and male in three patients. Among the eight reared as female, gender had been reassigned as male in three patients well before the present study was conducted. None of the eleven patients had gender dysphoria at the time of this study. Early gender of rearing was seen to be a critical indicator of present GI in our patients except in cases of 5aRD.
The identification of a spontaneous 47, XX, +21/46, XY chimeric fetus with male genitalia
Directory of Open Access Journals (Sweden)
Lee Kuei-Fang
2012-09-01
Full Text Available Abstract Background Approximately 30 sex-chromosome discordant chimera cases have been reported to date, of which only four cases carried trisomy 21. Here, we present an additional case, an aborted fetus with a karyotype of 47,XX, +21/46,XY. Case presentation Autopsy demonstrated that this fetus was normally developed and had male genitalia. Major characteristics of Down syndrome were not observed except an enlarged gap between the first and second toes. Karyotyping of tissues cultured from the fetus revealed the same chimeric chromosomal composition detected in the amniotic fluid but with a different ratio of [47,XX,+21] to [46,XY]. Further short tandem repeat analysis indicated a double paternal contribution and single maternal contribution to the fetus, with the additional chromosome 21 in the [47,XX,+21] cell lineage originating from the paternal side. Conclusion We thus propose that this chimeric fetus was formed via the dispermic fertilization of a parthenogenetic ovum with one (Y sperm and one (X,+21 sperm.
A novel hybrid actuation mechanism based XY nanopositioning stage with totally decoupled kinematics
Zhu, Wu-Le; Zhu, Zhiwei; Guo, Ping; Ju, Bing-Feng
2018-01-01
This paper reports the design, analysis and testing of a parallel two degree-of-freedom piezo-actuated compliant stage for XY nanopositioning by introducing an innovative hybrid actuation mechanism. It mainly features the combination of two Scott-Russell and a half-bridge mechanisms for double-stage displacement amplification as well as moving direction modulation. By adopting the leaf-type double parallelogram (LTDP) structures at both input and output ends of the hybrid mechanism, the lateral stiffness and dynamic characteristics are significantly improved while the parasitic motions are greatly eliminated. The XY nanopositioning stage is constructed with two orthogonally configured hybrid mechanisms along with the LTDP mechanisms for totally decoupled kinematics at both input and output ends. An analytical model was established to describe the complete elastic deformation behavior of the stage, with further verification through the finite element simulation. Finally, experiments were implemented to comprehensively evaluate both the static and dynamic performances of the proposed stage. Closed-loop control of the piezoelectric actuators (PEA) by integrating strain gauges was also conducted to effectively eliminate the nonlinear hysteresis of the stage.
One-norm geometric quantum discord and critical point estimation in the XY spin chain
Energy Technology Data Exchange (ETDEWEB)
Cheng, Chang-Cheng; Wang, Yao; Guo, Jin-Liang, E-mail: guojinliang80@163.com
2016-11-15
In contrast with entanglement and quantum discord (QD), we investigate the thermal quantum correlation in terms of Schatten one-norm geometric quantum discord (GQD) in the XY spin chain, and analyze their capabilities in detecting the critical point of quantum phase transition. We show that the one-norm GQD can reveal more properties about quantum correlation between two spins, especially for the long-range quantum correlation at finite temperature. Under the influences of site distance, anisotropy and temperature, one-norm GQD and its first derivative make it possible to detect the critical point efficiently for a general XY spin chain. - Highlights: • Comparing with entanglement and QD, one-norm GQD is more robust versus the temperature. • One-norm GQD is more efficient in characterization of long-range quantum correlation between two distant qubits. • One-norm GQD performs well in highlighting the critical point of QPT at zero or low finite temperature. • One-norm GQD has a number of advantages over QD in detecting the critical point of the spin chain.
Çatlı, Gönül; Alparslan, Caner; Can, P Şule; Akbay, Sinem; Kelekçi, Sefa; Atik, Tahir; Özyılmaz, Berk; Dündar, Bumin N
2015-06-01
46,XY pure gonadal dysgenesis (Swyer syndrome) is characterized by normal female genitalia at birth. It usually first becomes apparent in adolescence with delayed puberty and amenorrhea. Rarely, patients can present with spontaneous breast development and/or menstruation. A fifteen-year-old girl presented to our clinic with the complaint of primary amenorrhea. On physical examination, her external genitals were completely female. Breast development and pubic hair were compatible with Tanner stage V. Hormonal evaluation revealed a hypergonadotropic state despite a normal estrogen level. Chromosome analysis revealed a 46,XY karyotype. Pelvic ultrasonography showed small gonads and a normal sized uterus for age. SRY gene expression was confirmed by multiplex polymerase chain reaction. Direct sequencing on genomic DNA did not reveal a mutation in the SRY, SF1 and WT1 genes. After the diagnosis of Swyer syndrome was made, the patient started to have spontaneous menstrual cycles and therefore failed to attend her follow-up visits. After nine months, the patient underwent diagnostic laparoscopy. Frozen examination of multiple biopsies from gonad tissues revealed gonadoblastoma. With this report, we emphasize the importance of performing karyotype analysis, which is diagnostic for Swyer syndrome, in all cases with primary or secondary amenorrhea even in the presence of normal breast development. We also suggest that normal pubertal development in patients with Swyer syndrome may be associated with the presence of a hormonally active tumor.
A Novel Sex Chromosome Mosaicism 45,X/45,Y/46,XY/46,YY/47,XYY Causing Ambiguous Genitalia.
Khan, Muhammad Riaz; Bukhari, Ihtisham; Junxiang, Tang; Hui, Liu; Muhammad, Niaz; Fan, Cui; Zhu, Jiangsheng; Wu, Mian
2017-11-01
Sex chromosomal mosaicism has been considered as a major cause of human sexual differentiation disorders, like partial virilization and ambiguous genitalia. 45,X/46,XX, 45,X/46,XY and 46,XY/47,XXY are three most common sex chromosome mosaics associated with human ambiguous genitalia. Here, we report the case of a 3-year-old boy with ambiguous genitalia, bilateral cryptorchidism, and with an inguinal hernia. G banded cytological karyotyping and FISH analyses revealed that the patient has extremely rare and novel sex chromosome mosaic 45,X/45,Y/46,XY/46,YY/47,XYY karyotype. These cells exist in different percentages, important for phenotypic appearance of the patient. This is a first report of an unusual mosaic karyotype causing ambiguous genitalia. © 2017 by the Association of Clinical Scientists, Inc.
Tata Laksana Kasus Perempuan dengan Pure Gonadal Dysgenesis 46, XY (Sindrom Swyer
Directory of Open Access Journals (Sweden)
Kanadi Sumapradja
2016-06-01
Full Text Available Disorders of sex development (DSD adalah kelainan medis yang dikaitkan dengan ketidakcocokan antara kromosom, gonad dan fenotip. Sindrom Swyer adalah kelainan berupa disgenesis gonad 46,XY dan diikuti dengan tidak terjadinya pelepasan anti-mullerian hormone (AMH dari gonad yang mengalami disgenesis sehingga mengakibatkan berkembangnya duktus muller menjadi uterus. Keadaan tersebut mengakibatkan pasien mengeluh amenorea primer dan organ seks sekunder tidak berkembang. Orientasi gender umumnya adalah sebagai perempuan, karena kurangnya paparan hormon androgen terhadap otak. Tatalaksana kasus Disorders of sex development (DSD sangat mementingkan pasien (patient-centered sehingga tatalaksana medikamentosa maupun pembedahan harus berdasarkan pemahaman pasien terhadap orientasi gendernya. Pada makalah ini dilaporkan kasus sindrom swyer pada seorang perempuan usia 29 tahun dengan keluhan amenorea primer. Hasil analisis kromosom 46,XY (20 metafase dengan hormon follicle stimulating hormone (FSH 31.5miu/ml, luteinizing hormone (LH 10.8miu/ml, estradiol (E2 <5pg/ml, testosteron total (T <0.0025ng/ml. Tatalaksana medikamentosa adalah memberikan terapi hormon estrogen untuk membantu proses feminisasi. Karena risiko tinggi terjadinya tumor pada kasus disgenesis gonad intra-abdomen dengan kromosom Y, maka direncanakan tindakan gonadektomi. Kata kunci: Tatalaksana, Sindrom Swyer, pure gonadal dysgenesis Case Management of Pure Gonadal Dysgenesis 46, XY (Sindrom Swyer Abstract Disorders of sex development (DSD are medical conditions in which the development of chromosomal, gonadal or anatomic sex varies from normal and may be incongruent with each other. Swyer syndrome is a condition caused by pure gonadal dysgenesis 46,XY, which followed by inadequate anti-mullerian (AMH production results in maintenance and further development of mullerian duct into uterus. Therefore, many patients who suffer from this condition initially come with chief complaint of primary
Energy Technology Data Exchange (ETDEWEB)
Parente, Walter E.F.; Pacobahyba, J.T.M.; Araújo, Ijanílio G. [Departamento de Física, Universidade Federal de Roraima, BR 174, Km 12. Bairro Monte Cristo. CEP: 69300-000 Boa Vista, Roraima (Brazil); Neto, Minos A., E-mail: minos@pq.cnpq.br [Universidade Federal do Amazonas, Departamento de Física, 3000, Japiim, 69077-000, Manaus-AM (Brazil); Ricardo de Sousa, J. [Universidade Federal do Amazonas, Departamento de Física, 3000, Japiim, 69077-000, Manaus-AM (Brazil); National Institute of Science and Technology for Complex Systems, 3000, Japiim, 69077-000, Manaus-AM (Brazil); Akinci, Ümit [Department of Physics, Dokuz Eylül University, Tr-35160 Izmir (Turkey)
2014-04-15
In this paper we study the quantum spin-1/2 anisotropic Heisenberg antiferromagnet model in the presence of a Dzyaloshinskii–Moriya interaction (D) and a uniform longitudinal (H) magnetic field. Using the effective-field theory with a finite cluster N=2 spin (EFT-2) we calculate the phase diagrams in the H−T and D−T planes on a simple cubic lattice (z=6). We have only observed second order phase transitions for values between Δ∈[0,1], where the cases were analysed: Ising (Δ=1), anisotropic Heisenberg (Δ=0.6) and isotropic Heisenberg (Δ=0). - Highlights: • Anisotropic Heisenberg antiferromagnet on a simple cubic lattice. • Effective-field theory. • Dzyaloshinskii–Moriya interaction.
Köhler, Birgit; Kleinemeier, Eva; Lux, Anke; Hiort, Olaf; Grüters, Annette; Thyen, Ute
2012-02-01
Prenatal deficit of androgens or androgen action results in atypical genitalia in individuals with XY disorders of sex development (XY,DSD). XY,DSD include mainly disorders of gonadal development and testosterone synthesis and action. Previously, most XY,DSD individuals were assigned to the female sex. Constructive genital surgery allowing heterosexual intercourse, gonadectomy, and hormone therapy for feminization were often performed. However, outcome studies are scarce. Our objective was evaluation of satisfaction with genital surgery and sexual life in adults with XY,DSD. We evaluated 57 individuals with XY,DSD from the German multicenter clinical evaluation study with a condition-specific questionnaire. The individuals were divided into subgroups reflecting the absence/presence of partial androgen effect or genital constructive surgery. Dissatisfaction with function of the surgical result (47.1%) and clitoral arousal (47.4%) was high in XY,DSD partially androgenized females after feminization surgery. Dissatisfaction with overall sex life (37.5%) and sexual anxieties (44.2%) were substantial in all XY,DSD individuals. Problems with desire (70.6%), arousal (52.9%), and dyspareunia (56.3%) were significant in XY,DSD complete females. 46,XY partially androgenized females reported significantly more often partners of female (9.1%) or both sexes (18.2%) and dyspareunia (56.5%) compared with controls. Individuals with complete androgen insensitivity syndrome stated significant problems with desire (81.8%), arousal (63.6%), and dyspareunia (70%). Care should be improved in XY,DSD patients. Constructive genital surgery should be minimized and performed mainly in adolescence or adulthood with the patients' consent. Individuals with DSD and their families should be informed with sensibility about the condition. Multidisciplinary care with psychological and nonprofessional support (parents, peers, and patients' support groups) is mandatory from child to adulthood.
Ramesh Kumar Moona Haji Mohamed; Che Supian Mohamad Nor
2013-01-01
The purpose of this paper is to trace McGregor’s X-Y theory and its relationship with fulfillment of psychological contract. This is a review article relying on literature reviews and synthesizing concepts and ideas from related sources. McGregor’s X-Y theory is a natural rule for managing people. McGregor’s ideas suggest that there are two fundamental approaches to managing people. Theory X management style generally get poor results compare with managers use theory Y, which produces better ...
DEFF Research Database (Denmark)
Müller, J; Torsson, A; Damkjaer Nielsen, M
1991-01-01
and 8 years). In the surviving individuals, the diagnosis was established during the first 2-4 months of life by extensive endocrine studies of blood and urine. In the remaining patient, the diagnosis was made on the basis of karyotype (46,XY), anatomy of internal and external genitalia and adrenal...... pathology. Gonadectomy was performed in the 2 surviving 46,XY individuals at the age of 7 years, and histological examination showed normal testicular morphology but very few germ cells. Postmortem examination of the testes of the 2-month-old subject showed normal testicular histology, and quantitative...
Energy Technology Data Exchange (ETDEWEB)
Rechenberg, Helmut [MPI fuer Physik, Muenchen (Germany). Werner-Heisenberg-Institut
2010-07-01
With his discovery that measuring values of complementary fundamental quantities in the microscopic world cannot by arbitrarily precisely determined cutted Werner Heisenberg the Gordian knot for the finishing of quantum theory developed by Planck, Einstein, and others and opened by this a new ''golden era'' in the physics of the 20th century. On the base of the documents from his life and work, i. e. deeds, letters and reports of contemporaries, as well as the published and unpublished essays, books, and articles of Heisenberg - also the later on found, publications or manuscripts mainly coming from the inheritance - resulted this systematic biography of Heisenberg. The author, the last doctoral candidate of Heisenberg relied furthermore on factual and personal knowledges, mainly own remembrances on his doctoral father and his teachers, colleagues, and students. Because of the interest of an authentical biography of the theoretical physicist Heisenberg the presentation of the mathematical approaches and the corresponding derivations could not completely be abandoned. This biography appeals by this both to a scientifically cultivated as a wider in science interested audience and covers the first phase of Heisenberg's life until his Nobel price 1933. [German] Mit seiner Entdeckung, dass sich Messwerte komplementaerer Groessen in der mikroskopischen Welt nicht beliebig genau bestimmen lassen, durchschnitt Werner Heisenberg den Gordischen Knoten zur Vollendung der von Planck, Einstein und anderen entwickelten Quantentheorie und eroeffnete damit ein neues ''goldenes Zeitalter'' in der Physik des 20. Jahrhunderts. Auf der Grundlage der Dokumente aus seinem Leben und Wirken, d.h. der Urkunden, Briefe und Berichte von Zeitzeugen sowie der publizierten und unpublizierten Abhandlungen, Buecher und Artikel Heisenbergs - auch der spaeter aufgefundenen, ueberwiegend aus dem Nachlass Heisenbergs stammenden Veroeffentlichungen oder
McCartin, Brian J.
2008-01-01
This note presents geometric and physical interpretations of the sufficient condition for a critical point to be a strict relative extremum: f[subscript xx]f[subscript yy] - f[superscript 2][subscript xy] greater than 0. The role of the double derivative f[subscript xy] in this inequality will be highlighted in these interpretations. (Contains 14…
Gomes, N; Clay, R T; Mazumdar, S
2013-09-25
A frustrated, effective ½-filled band Hubbard-Heisenberg model has been proposed for describing the strongly dimerized charge-transfer solid families κ-(ET)2X and Z[Pd(dmit)2]2. In addition to showing unconventional superconductivity, these materials also exhibit antiferromagnetism, candidate spin-liquid phases, and, in the case of Z=EtMe3P, a spin-gapped phase that has sometimes been referred to as a valence bond solid. We show that neither superconductivity nor the valence bond order phase occurs within the Hubbard-Heisenberg model. We suggest that a description based on ¼-filling, that is reached when the carrier concentration per molecule instead of per dimer is considered, thus may be appropriate.
Alcance y Función de las Teorias Físicas em Hylary Putnam y Werner Heisenberg
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Christian de Ronde
2013-08-01
Full Text Available In this work we attempt to analyze the intra-theoretic characterization provided by Hilary Putnam and Werner Heisenberg between quantum mechanics and other theories. The first defended the idea that physical theories include macro principles that under specific definite historical conditions can be revised on the light of rival principles. Putnam will concentrate in the impact that quantum mechanics has produced in the classical image of knowledge. Heisenberg, on the other hand, develops his analysis from the notion of closed theories, assuming the independence and incommensurability of physical theories. These divergences between the two authors will allow us to analyze how the disagreement in the consideration of the status of physical theories, goes deeper into more profound aspects related to the nature of knowledge and the relation between theory and world
Gomes, N.; Clay, R. T.; Mazumdar, S.
2013-09-01
A frustrated, effective \\frac{1}{2}-filled band Hubbard-Heisenberg model has been proposed for describing the strongly dimerized charge-transfer solid families κ-(ET)2X and Z[Pd(dmit)2]2. In addition to showing unconventional superconductivity, these materials also exhibit antiferromagnetism, candidate spin-liquid phases, and, in the case of Z=EtMe3P, a spin-gapped phase that has sometimes been referred to as a valence bond solid. We show that neither superconductivity nor the valence bond order phase occurs within the Hubbard-Heisenberg model. We suggest that a description based on \\frac{1}{4}-filling, that is reached when the carrier concentration per molecule instead of per dimer is considered, thus may be appropriate.
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N. Manojlović
2017-10-01
Full Text Available The implementation of the algebraic Bethe ansatz for the XXZ Heisenberg spin chain in the case, when both reflection matrices have the upper-triangular form is analyzed. The general form of the Bethe vectors is studied. In the particular form, Bethe vectors admit the recurrent procedure, with an appropriate modification, used previously in the case of the XXX Heisenberg chain. As expected, these Bethe vectors yield the strikingly simple expression for the off-shell action of the transfer matrix of the chain as well as the spectrum of the transfer matrix and the corresponding Bethe equations. As in the XXX case, the so-called quasi-classical limit gives the off-shell action of the generating function of the corresponding trigonometric Gaudin Hamiltonians with boundary terms.
Esplin, Edward D; Chaib, Hassan; Haney, Michael; Martin, Brock; Homeyer, Margaret; Urban, Alexander E; Bernstein, Jonathan A
2015-06-01
The association of 46,XY disorder of sex development (DSD) with congenital diaphragmatic hernia (CDH) is rare, but has been previously described with and without other congenital anomalies. Literature review identified five cases of 46,XY DSD associated with CDH and other congenital anomalies. These five cases share characteristics including CDH, 46,XY karyotype with external female appearing or ambiguous genitalia, cardiac anomalies, and decreased life span. The present case had novel features including truncus arteriosus, bifid thymus, gut malrotation, and limb anomalies consisting of rhizomelia and adactyly. With this case report, we present a review of the literature of cases of 46,XY DSD and CDH in association with multiple congenital abnormalities. This case may represent a unique syndrome of 46,XY DSD and diaphragmatic hernia or a more severe presentation of a syndrome represented in the previously reported cases. © 2015 Wiley Periodicals, Inc.
Poisson Lie symmetry and D-branes in WZW model on the Heisenberg Lie group H4
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A. Eghbali
2015-10-01
Full Text Available We show that the WZW model on the Heisenberg Lie group H4 has Poisson–Lie symmetry only when the dual Lie group is A2⊕2A1. In this way, we construct the mutual T-dual sigma models on Drinfel'd double generated by the Heisenberg Lie group H4 and its dual pair, A2⊕2A1, as the target space in such a way that the original model is the same as the H4 WZW model. Furthermore, we show that the dual model is conformal up to two-loop order. Finally, we discuss D-branes and the worldsheet boundary conditions defined by a gluing matrix on the H4 WZW model. Using the duality map obtained from the canonical transformation description of the Poisson–Lie T-duality transformations for the gluing matrix which locally defines the properties of the D-brane, we find two different cases of the gluing matrices for the WZW model based on the Heisenberg Lie group H4 and its dual model.
Exact solution of the mixed spin-1/2 and spin-S Ising-Heisenberg diamond chain
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L. Čanová
2009-01-01
Full Text Available The geometric frustration in a class of the mixed spin-1/2 and spin-S Ising-Heisenberg diamond chains is investigated by combining three exact analytical techniques: Kambe projection method, decoration-iteration transformation and transfer-matrix method. The ground state, the magnetization process and the specific heat as a function of the external magnetic field are particularly examined for different strengths of the geometric frustration. It is shown that the increase of the Heisenberg spin value S raises the number of intermediate magnetization plateaux, which emerge in magnetization curves provided that the ground state is highly degenerate on behalf of a sufficiently strong geometric frustration. On the other hand, all intermediate magnetization plateaux merge into a linear magnetization versus magnetic field dependence in the limit of classical Heisenberg spin S → ∞. The enhanced magnetocaloric effect with cooling rate exceeding the one of paramagnetic salts is also detected when the disordered frustrated phase constitutes the ground state and the external magnetic field is small enough.
An XXX male resulting from paternal X-Y interchange and maternal X-X nondisjunction.
Annerén, G; Andersson, M; Page, D C; Brown, L G; Berg, M; Läckgren, G; Gustavson, K H; de la Chapelle, A
1987-01-01
A 2-year-old boy was found to have a 47,XXX karyotype. Restriction-fragment-length-polymorphism analysis showed that, of his three X chromosomes, one is of paternal and two are of maternal origin. The results of Y-DNA hybridization were reminiscent of those in XX males in two respects. First, hybridization to Southern transfers revealed the presence in this XXX male of sequences derived from the Y-chromosomal short arm. Second, in situ hybridization showed that this Y DNA was located on the tip of the X-chromosomal short arm. We conclude that this XXX male resulted from the coincidence of X-X nondisjunction during maternal meiosis and aberrant X-Y interchange either during or prior to paternal meiosis. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:2889356
Anisotropy in the helicity modulus of a quantum three-dimensional XY model: application to YBCO
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Mitrovic, Bozidar; Samokhin, Kirill; Bose, Shyamal K [Physics Department, Brock University, St Catharines, ON, L2S 3A1 (Canada)
2003-11-12
We present a variational study of the helicity moduli of an anisotropic quantum three-dimensional (3D) XY model of YBCO in its superconducting state. It is found that both the ab-plane and the c-axis helicity moduli, which are proportional to the inverse square of the corresponding magnetic field penetration depth, vary with temperature T as T{sup 4} in the zero temperature limit. Moreover, the c-axis helicity modulus drops with temperature much faster than the ab-plane helicity modulus because of the weaker Josephson couplings along the c-axis compared to those along the ab-plane. These findings are in disagreement with experiments on high quality samples of YBCO.
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Hui, Ning-Ju [Department of Applied Physics, Xi' an University of Technology, Xi' an 710054 (China); Xu, Yang-Yang; Wang, Jicheng; Zhang, Yixin [Jiangsu Provincial Research Center of Light Industrial Optoelectronic Engineering and Technology, School of Science, Jiangnan University, Wuxi 214122 (China); Hu, Zheng-Da, E-mail: huyuanda1112@jiangnan.edu.cn [Jiangsu Provincial Research Center of Light Industrial Optoelectronic Engineering and Technology, School of Science, Jiangnan University, Wuxi 214122 (China)
2017-04-01
We investigate the properties of geometric quantum coherence in the XY spin-1/2 chain with staggered Dzyaloshinsky-Moriya interaction via the quantum renormalization-group approach. It is shown that the geometric quantum coherence and its coherence susceptibility are effective to detect the quantum phase transition. In the thermodynamic limit, the geometric quantum coherence exhibits a sudden jump. The coherence susceptibilities versus the anisotropy parameter and the Dzyaloshinsky-Moriya interaction are infinite and vanishing, respectively, illustrating the distinct roles of the anisotropy parameter and the Dzyaloshinsky-Moriya interaction in quantum phase transition. Moreover, we also explore the finite-size scaling behaviors of the coherence susceptibilities. For a finite-size chain, the coherence susceptibility versus the phase-transition parameter is always maximal at the critical point, indicating the dramatic quantum fluctuation. Besides, we show that the correlation length can be revealed by the scaling exponent for the coherence susceptibility versus the Dzyaloshinsky-Moriya interaction.
Relación entre quimerismo xx/xy y el fenotipo pseudohermafrodita masculino en porcinos.
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Reinartz E. Mónica
2001-09-01
Full Text Available La causa genética del pseudohermafroditismo no está bien dilucidada, sin embargo se han reportado distintos casos de pseudohermafroditas masculinos los cuales en la mayoría de los casos se han tratado de explicar por efectos hormonales sobre las gónadas en formación durante el desarrollo embrionario. Además se ha explorado poco la relación de este fenotipo con la constitución genómica de los organismos que presentan la disfunción sexual. En el presente trabajo se encontró una fuerte relación entre el quimerismo cromosómico XX/XY y el fenotipo pseudohermafrodita masculino exhibido por dos ejemplares de porcinos Landrace X Largewhite similar a lo encontrado en freemartinismo de bovinos.
Mosaic 35,X/36,XY karyotype and intersex in a red panda (Ailurus fulgens fulgens).
Reddacliff, G L; Halnan, C R; Martin, I C
1993-01-01
A zoo-bred Himalayan red panda (Ailurus fulgens fulgens) was diagnosed as a presumptive intersex on clinical examination at 4-mo-of-age. The phenotype was predominantly female but showed a large anogenital distance and bilateral ischial swellings. Based on cytogenetic evaluation, the karyotype was mos35,X/36,XY, with 50% of each cell type. A grossly normal uterus and oviducts were seen with laparoscopic examination, while the gonads were smooth-surfaced, with a ramifying vascular pattern. On histopathologic examination the bulk of the gonads consisted of clumps of poorly differentiated cells, with just a thin rim of ovarian tissue under the region covered by the fimbriae of the oviduct.
Gender dysphoria and gender change in an adolescent with 45,X/46,XY mixed gonadal dysgenesis.
Ocal, G; Berberoğlu, M; Siklar, Z; Bilir, P
2009-06-01
This is a report of a 13-year-old 45,X/46,XY patient who was assigned as female gender and had feminizing surgery during infancy. Psychological problems became progressively more severe from childhood to incapitation by age 13 years. Gender identity reversal was performed after extensive physiological testing. Because he wanted to have corrective surgery, his external genitalia sex reassignment was made male from female. There were surgical problems with his phalloplasty; after surgery at infancy there was reduction of the phallus with recession of the glans to the typical clitoral location. Genital response during sexual activity and satisfaction after reconstructive surgery for male genitalia are as yet unknown. This patient is a typical example for medical, psychological and surgical dilemmas of sex reassignment and the problems of early corrective surgery. Sufficient brain virilisation associated with undervirilised external genitalia is an important problem for assignment of gender identity.
Fukuda, Masahiro; Watanabe, Kazuhiro; Sakashita, Mitsuo; Kurosawa, Masashi; Nakatsuka, Osamu; Zaima, Shigeaki
2017-10-01
The energy band alignment of Ge1-x Sn x /Ge1-x-y Si x Sn y heterostructures was investigated, and control of the valence band offset at the Ge1-x Sn x /Ge1-x-y Si x Sn y heterointerface was achieved by controlling the Si and Sn contents in the Ge1-x-y Si x Sn y layer. The valence band offset in the Ge0.902Sn0.098/Ge0.41Si0.50Sn0.09 heterostructure was evaluated to be as high as 330 meV, and its conduction band offset was estimated to be 150 meV by considering the energy bandgap calculated from the theoretical prediction. In addition, the formation of the strain-relaxed Ge1-x-y Si x Sn y layer was examined and the crystalline structure was characterized. The epitaxial growth of a strain-relaxed Ge0.64Si0.21Sn0.15 layer with the degree of strain relaxation of 55% was examined using a virtual Ge substrate. Moreover, enhancement of the strain relaxation was demonstrated by post-deposition annealing, where a degree of strain relaxation of 70% was achieved after annealing at 400 °C. These results indicate the possibility for enhancing the indirect-direct crossover with a strained and high-Sn-content Ge1-x Sn x layer on a strain-relaxed Ge1-x-y Si x Sn y layer, realizing preferable carrier confinement by type-I energy band alignment with high conduction and valence band offsets.
A NEW HYPOTHESIS ON THE EVOLUTION OF SEX DETERMINATION IN VERTEBRATES - BIG FEMALES ZW, BIG MALES XY
KRAAK, SBM; DELOOZE, EMA
1993-01-01
Why are there two chromosomal sex-determining mechanisms in vertebrates; ZW/ZZ, meaning female heterogamety, and XX/XY, meaning male heterogamety? We propose an evolutionary explanation. Transition from environmental sex determination to genetic sex determination can result when an allele that
Bhagavath, Bala; Layman, Lawrence C; Ullmann, Reinhard; Shen, Yiping; Ha, Kyungsoo; Rehman, Khurram; Looney, Stephen; McDonough, Paul G; Kim, Hyung-Goo; Carr, Bruce R
2014-08-05
46,XY sex reversal is a rare disorder and familial cases are even more rare. The purpose of the present study was to determine the molecular basis for a family with three affected siblings who had 46,XY sex reversal. DNA was extracted from three females with 46,XY sex reversal, two normal sisters, and both unaffected parents. All protein coding exons of the SRY and NR5A1 genes were subjected to PCR-based DNA sequencing. In addition, array comparative genomic hybridization was performed on DNA from all seven family members. A deletion was confirmed using quantitative polymerase chain reaction. Expression of SOX9 gene was quantified using reverse transcriptase polymerase chain reaction. A 349kb heterozygous deletion located 353kb upstream of the SOX9 gene on the long arm of chromosome 17 was discovered in the father and three affected siblings, but not in the mother. The expression of SOX9 was significantly decreased in the affected siblings. Two of three affected sisters had gonadoblastomas. This is the first report of 46,XY sex reversal in three siblings who have a paternally inherited deletion upstream of SOX9 associated with reduced SOX9 mRNA expression. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Andrade, Juliana Gabriel Ribeiro de; Andrade, Liliana Aparecida Lucci De Angelo; Guerra-Junior, Gil; Maciel-Guerra, Andréa Trevas
2017-08-28
The 45,X/46,XY karyotype has been associated with mixed gonadal dysgenesis (MGD) and ovotesticular disorder of sex development (DSD). Our aim was to revise the diagnosis of ovotesticular DSD in two patients in the context of a retrospective study of 45,X/46,XY subjects with genital ambiguity. Patient 1 had a left streak gonad; the right one was considered an ovotestis. Patient 2 had a right testis; the left gonad was considered an ovary. Revision of the histological sections was performed. Both the "ovarian" part of the right gonad of patient 1 and the left "ovary" of patient 2 contained ovarian-type stroma with clusters of sex-cordlike structures and rare germ cells, compatible with undifferentiated gonadal tissue (UGT). Misdiagnosis of ovarian tissue in patients with 45,X/46,XY mosaicism or its variants could also be found in six published case reports. A distinction between 45,X/46,XY ovotesticular DSD and MGD should be made on past and future cases keeping in mind that UGT may be mistaken as ovarian tissue.
Norling, Ameli; Lindén Hirschberg, Angelica; Iwarsson, Erik; Persson, Bengt; Wedell, Anna; Barbaro, Michela
2013-12-01
Half of all patients with a disorder of sex development (DSD) do not receive a specific molecular diagnosis. Comparative genomic hybridization (CGH) can detect copy number changes causing gene haploinsufficiency or over-expression that can lead to impaired gonadal development and gonadal DSD. The purpose of this study was to identify novel candidate genes for 46,XY gonadal dysgenesis (GD) using a customized 1 M array-CGH platform with whole-genome coverage and probe enrichment targeting 78 genes involved in sex development. Fourteen patients with 46,XY gonadal DSD were enrolled in the study. Nine individuals were analyzed by array CGH. All patients were included in a follow up sequencing study of candidate genes. Three novel candidate regions for 46,XY GD were identified in two patients. An interstitial duplication of the SUPT3H gene and a deletion of C2ORF80 were detected in a pair of affected siblings. Sequence analysis of these genes in all patients revealed no additional mutations. A large duplication highlighting PIP5K1B, PRKACG and FAM189A2 as candidates for 46,XY GD, were also detected. All five genes are expressed in testicular tissues, and one is shown to cause gonadal DSD in mice. However detailed functional information is lacking for these genes. Copyright © 2013 The Authors. Published by Elsevier Masson SAS.. All rights reserved.
Growth in Boys with 45,X/46,XY Mosaicism: Effect of Growth Hormone Treatment on Statural Growth.
Bertelloni, Silvano; Baroncelli, Giampiero I; Massart, Francesco; Toschi, Benedetta
2015-01-01
45,X/46,XY mosaicism is a rare sex chromosome disorder of sex development. Short stature is a main feature of boys with this condition. Different causes likely contribute to growth impairment. Growth hormone (GH) has been administered to treat short stature in boys with 45,X/46,XY mosaicism, but conflicting data are available. Here, spontaneous growth patterns as well as short- and long-term follow-up studies during GH therapy in these patients are reviewed. Short- and mid-term data showed an improvement of the growth pattern in GH-treated boys, mainly when hormonal therapy was started early, while long-term follow-up demonstrated similar adult heights in GH-treated and untreated patients. Individual biological factors (e.g. different chromosome constitution, different mosaicism among various tissues, impaired pubertal growth spurt), non-homogeneous GH doses and different ages at start of therapy may contribute to the variable results. Thus, early GH therapy at pharmacological doses may improve the growth pattern of short boys with 45,X/46,XY mosaicism, but data on adult height are disappointing. Evaluation of larger patient samples treated by homogeneous doses and long-term follow-up studies assessing adult height and safety are needed to reach definitive conclusions on GH therapy in boys with 45,X/46,XY mosaicism. © 2015 S. Karger AG, Basel.
Radial velocities for contact binaries. 2. TZ Boo, XY Boo, TX Cnc, RZ Com, CC Com and Y Sex
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McLean, B.J.; Hilditch, R.W. (Saint Andrews Univ. (UK). Observatory)
1983-04-01
Radial velocity observations obtained using digital reduction techniques are presented for a further six W Ursae Majoris-type contact binaries, namely TZ Boo, XY Boo, TX Cnc, RZ Com, CC Com and Y Sex. The derived spectroscopic mass ratios are found to be in good agreement with the photometric mass ratios determined by light curve synthesis techniques.
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Po-Chun Ko
2007-09-01
Conclusion: This is the first report of triplet pregnancy complicated with one complete hydatidiform mole and preeclampsia in a 46, XY female with gonadal dysgenesis. Our case demonstrated that prolonged gestation with both surviving fetuses was possible by applying intensive monitoring of the whole pregnancy.
An infant with mos45,X/46,XY/47,XYY/48,XYYY: Genetic and clinical findings
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Fox, J.; Blumenthal, D.; Brock, W. [Long Island Jewish Medical Center, New Hyde Park, NY (United States)] [and others
1994-09-01
We report on an infant with mos45,X/46,XY/47,XYY/48,XYYY who presented with ambiguous genitalia. The patient was the 2,637 gram product of a 38 week gestation and elective repeat C-section born to a 35 year old G3P2 mother. The pregnancy was complicated by placenta previa. There was no history of maternal health problems or drug or steroid use. At birth bilateral epicanthal folds and overfolded helices were noted without webbing of the neck or lymphedema. There was a phallic structure measuring 1.5 cm with dorsal hood and midline cleft with a normal female introitus, urethra, and vagina. Congenital adrenal hyperplaxia was excluded. Renal ultrasound was normal. Periperal blood chromosomes revealed a mos45,X(38%)/47,XYY(29%)/48,XYYY(33%) karyotype. Echocardiography revealed coarctation of the aorta and a bicuspid aortic valve. An additional cell line, 46,XY, was identified in aortic tissue obtained at the time of surgery. At age 15 months she was 25% in height and weight and had bilateral ptosis. Her development was within normal limits, but no words except {open_quotes}Mama{close_quotes} or {open_quotes}Dada{close_quotes} were spoken. A left intraabdominal testis with epididymis and dilated tubules and bilateral Fallopian tubes were removed at laparoscopy/reconstruction. Cell cultures were initiated from gonadal tissue, and karyotypes are pending. Patients with mosaic Y chromosome aneuploidy involving 2 Y chromosomes are rare. Eighteen patients with 45,X/47,XYY have been described; prenatally diagnosed cases appeared to be normal male whereas cases diagnosed postnally presented with ambiguous genitalia and/or other anomalies. The phenotype of Y chromosome aneuploidy with 3 Y chromosomes is even more unpredictable due to the paucity of reported cases. To our knowledge this is the first patient described with this unusual karyotype, thus adding to the limited information of patients with rare mosaic Y chromosome aneuploidy.
Local quantum criticality in the two-dimensional dissipative quantum XY model
Zhu, Lijun; Chen, Yan; Varma, Chandra M.
2015-05-01
We use quantum Monte Carlo simulations to calculate the phase diagram and the correlation functions for the quantum phase transitions in the two-dimensional dissipative quantum XY model with and without fourfold anisotropy. Without anisotropy, the model describes the superconductor-to-insulator transition in two-dimensional dirty superconductors. With anisotropy, the model represents the loop-current order observed in the underdoped cuprates and its fluctuations, as well as the fluctuations near the ordering vector in simple models of two-dimensional itinerant ferromagnets and itinerant antiferromagnets. These calculations test an analytic solution of the model which reexpressed it in terms of topological excitations: the vortices with interactions only in space but none in time, and warps with leading interactions only in time but none in space, as well as subleading interactions which are both space and time dependent. For parameters where the proliferation of warps dominates the phase transition, the critical fluctuations as functions of the deviation of the dissipation parameter α on the disordered side from its critical value αc are scale invariant in imaginary time τ as the correlation length in time ξτ=τce[αc/(αc-α ) ] 1 /2 diverges, where τc is a short-time cutoff. On the other hand, the spatial correlations develop with a correlation length ξx≈ξ0ln(ξτ) , with ξ0 of the order of a lattice constant. The dynamic correlation exponent z is therefore ∞ . The Monte Carlo calculations also directly show warps and vortices. Their densities and correlations across the various transitions in the model are calculated and related to those of the order-parameter correlations in the dissipative quantum XY model.
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Marco Barchi
2008-05-01
Full Text Available During meiosis in most sexually reproducing organisms, recombination forms crossovers between homologous maternal and paternal chromosomes and thereby promotes proper chromosome segregation at the first meiotic division. The number and distribution of crossovers are tightly controlled, but the factors that contribute to this control are poorly understood in most organisms, including mammals. Here we provide evidence that the ATM kinase or protein is essential for proper crossover formation in mouse spermatocytes. ATM deficiency causes multiple phenotypes in humans and mice, including gonadal atrophy. Mouse Atm-/- spermatocytes undergo apoptosis at mid-prophase of meiosis I, but Atm(-/- meiotic phenotypes are partially rescued by Spo11 heterozygosity, such that ATM-deficient spermatocytes progress to meiotic metaphase I. Strikingly, Spo11+/-Atm-/- spermatocytes are defective in forming the obligate crossover on the sex chromosomes, even though the XY pair is usually incorporated in a sex body and is transcriptionally inactivated as in normal spermatocytes. The XY crossover defect correlates with the appearance of lagging chromosomes at metaphase I, which may trigger the extensive metaphase apoptosis that is observed in these cells. In addition, control of the number and distribution of crossovers on autosomes appears to be defective in the absence of ATM because there is an increase in the total number of MLH1 foci, which mark the sites of eventual crossover formation, and because interference between MLH1 foci is perturbed. The axes of autosomes exhibit structural defects that correlate with the positions of ongoing recombination. Together, these findings indicate that ATM plays a role in both crossover control and chromosome axis integrity and further suggests that ATM is important for coordinating these features of meiotic chromosome dynamics.
Aetiological bases of 46,XY disorders of sex development in the Hong Kong Chinese population.
Chan, Angel O K; But, W M; Lee, C Y; Lam, Y Y; Ng, K L; Loung, P Y; Lam, Aimen; Cheng, C W; Shek, C C; Wong, W S; Wong, K F; Wong, M Y; Tse, W Y
2015-12-01
Disorders of sex development are due to congenital defects in chromosomal, gonadal, or anatomical sex development. The objective of this study was to determine the aetiology of this group of disorders in the Hong Kong Chinese population. Five public hospitals in Hong Kong. Patients with 46,XY disorders of sex development under the care of paediatric endocrinologists between July 2009 and June 2011. Measurement of serum gonadotropins, adrenal and testicular hormones, and urinary steroid profiling. Mutational analysis of genes involved in sexual differentiation by direct DNA sequencing and multiplex ligation-dependent probe amplification. Overall, 64 patients were recruited for the study. Their age at presentation ranged from birth to 17 years. The majority presented with ambiguous external genitalia including micropenis and severe hypospadias. A few presented with delayed puberty and primary amenorrhea. Baseline and post-human chorionic gonadotropin-stimulated testosterone and dihydrotestosterone levels were not discriminatory in patients with or without AR gene mutations. Of the patients, 22 had a confirmed genetic disease, with 11 having 5α-reductase 2 deficiency, seven with androgen insensitivity syndrome, one each with cholesterol side-chain cleavage enzyme deficiency, Frasier syndrome, NR5A1-related sex reversal, and persistent Müllerian duct syndrome. Our findings suggest that 5α-reductase 2 deficiency and androgen insensitivity syndrome are possibly the two most common causes of 46,XY disorders of sex development in the Hong Kong Chinese population. Since hormonal findings can be unreliable, mutational analysis of the SRD5A2 and AR genes should be considered the first-line tests for these patients.
Frelich, Agnieszka; Frelich, Jakub; Jeż, Wacław; Irzyniec, Tomasz
2017-01-01
A 45,X/46,XY karyotype in women with Turner syndrome (TS) is very rare. The presence of a Y chromosome in the karyotype causes phenotypic differences and increased risk for neoplastic disease, compared to TS-women with other karyotypes. Our study addresses an issue: non-genital phenotypic differences between TS-patients with a Y-chromosome of their karyotype and TS-women without it. Results from patient history/physical examinations of the head and neck of eight TS-women and the 45,X/46,XY karyotype were compared with those observed in 164 TS-women and 30 controls. The heights of TS-groups: 142.5 ± 7.2 and 144.9 ± 7.2 cm were lower than controls (165.2 ± 6.6 cm). Participants were examined from 1995 to 2014. Among 28 study parameters, 15 were more frequently observed in TS women with the 45,X/46,XY karyotype compared to controls. Only abnormalities in the oral cavity and a history of childhood lymphoedema, differed significantly in the TS groups. With respect to the head and neck, the patient history and physical examination results of TS-women and the 45,X/46,XY karyotype and TS and other karyotypes revealed similar differences compared to controls. Compared to others TS patients, 45,X/46,XY individuals might more frequently have oral cavity soft tissue abnormalities and more rarely a history of childhood lymphoedema. (Endokrynol Pol 2017; 68 (1): 47-52).
Chen, Guang; Dou, Jingtao; Yang, Guoqing; Gu, Weijun; Du, Jin; Chen, Kang; Zang, Li; Jin, Nan; Wang, Xianling; Yang, Lijuan; Lyu, Zhaohui; Ba, Jianming; Lu, Juming; Li, Jiangyuan; Pan, Changyu; Mu, Yiming
2015-11-01
To investigate the clinical features, therapeutic regimens and follow-up information of patients with 45, X/46, XY mixed gonadal dysgenesis in order to improve the diagnosis and treatment of the disease. We performed a retrospective review of patients with 45, X/46, XY mosaicism hospitalized in Chinese PLA General Hospital between 2000 and 2014. The clinical features,sex hormones,treatment and follow-up information were summarized. (1) Seven patients ranging 12-17 years old were diagnosed as having 45, X/46, XY mixed gonadal dysgenesis. Six of them had female sex of rearing and one had male. (2) All of them presented with short stature and growth retardation, and had similar specific somatic signs to Turner syndrome. (3) The external genitalia presented with a wide variety of phenotypes. One patient presented with male phenotype with hypospadia, one presented with clitoridauxe, and five presented with female phenotype. The masculinization scores for the external genitalia showed that five patients presented with female phenotype, one patient with mild undervirilization and one patient with ambiguous genitalia. (4) By surgical exploration and ultrasound, two patients were found with testes and one was with ovary-like gonads. No gonad could be detected in the other four patients. (5) Five patients were treated with recombinant human growth hormone (rhGH). Two patients received sex hormone replacement therapy with one patient taking testosterone, whose penis became enlarged and erect after treatment, and one taking artificial cycle. The patients with 45, X/46, XY mosaicism share similar specific somatic signs to Turner syndrome. The 45, X/46, XY mosaicism presents with a wide spectrum of phenotypes with the highest proportion of being genital ambiguity. RhGH, testosterone and artificial cycle can be used accordingly.
Hamid, Arian Zad
2016-12-01
We analytically investigate Multiple Quantum (MQ) NMR dynamics in a mixed-three-spin (1/2,1,1/2) system with XXX Heisenberg model at the front of an external homogeneous magnetic field B. A single-ion anisotropy property ζ is considered for the spin-1. The intensities dependence of MQ NMR coherences on their orders (zeroth and second orders) for two pairs of spins (1,1/2) and (1/2,1/2) of the favorite tripartite system are obtained. It is also investigated dynamics of the pairwise quantum entanglement for the bipartite (sub)systems (1,1/2) and (1/2,1/2) permanently coupled by, respectively, coupling constants J}1 and J}2, by means of concurrence and fidelity. Then, some straightforward comparisons are done between these quantities and the intensities of MQ NMR coherences and ultimately some interesting results are reported. We also show that the time evolution of MQ coherences based on the reduced density matrix of the pair spins (1,1/2) is closely connected with the dynamics of the pairwise entanglement. Finally, we prove that one can introduce MQ coherence of the zeroth order corresponds to the pair spins (1,1/2) as an entanglement witness at some special time intervals.
Thermal quantum coherence and correlations in a spin-1 Heisenberg model
Xu, Ping; Hu, Yi-Hai; Hou, Xi-Wen
2018-02-01
The l1 norm and the relative entropy have been recently proposed as a information measure of quantum coherence (Baumgratz et al., 2014). Here their properties are studied for the thermal quantum state in a spin-1 Heisenberg model with various couplings, external magnetic fields, and temperatures as well. Quantum correlations quantified via quantum discord, quantum deficit, and the generalized negativity are simulated for reference. It is shown that quantum coherence, discord, and deficit are nonzero whereas the negativity is zero in some ranges of model parameters and temperature. Moreover, quantum coherence, discord, and deficit are more robust than the negativity against temperature and magnetic field. However, all those quantities at lower temperatures behave similarly. Remarkably, quantum deficit exhibits double sudden changes under suitable conditions while quantum coherence, discord, and entanglement do not display such a phenomenon. The hierarchy of two coherence measures and the hierarchy of quantum discord and deficit are discussed. Those are useful for understanding quantumness in high-dimensional mixed states and quantum tasks.
Spin wave dynamics in Heisenberg ferromagnetic/antiferromagnetic single-walled nanotubes
Energy Technology Data Exchange (ETDEWEB)
Mi, Bin-Zhou, E-mail: mbzfjerry2008@126.com [Department of Basic Curriculum, North China Institute of Science and Technology, Beijing 101601 (China); Department of Physics, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083 (China)
2016-09-15
The spin wave dynamics, including the magnetization, spin wave dispersion relation, and energy level splitting, of Heisenberg ferromagnetic/antiferromagnetic single-walled nanotubes are systematically calculated by use of the double-time Green’s function method within the random phase approximation. The role of temperature, diameter of the tube, and wave vector on spin wave energy spectrum and energy level splitting are carefully analyzed. There are two categories of spin wave modes, which are quantized and degenerate, and the total number of independent magnon branches is dependent on diameter of the tube, caused by the physical symmetry of nanotubes. Moreover, the number of flat spin wave modes increases with diameter of the tube rising. The spin wave energy and the energy level splitting decrease with temperature rising, and become zero as temperature reaches the critical point. At any temperature, the energy level splitting varies with wave vector, and for a larger wave vector it is smaller. When pb=π, the boundary of first Brillouin zone, spin wave energies are degenerate, and the energy level splittings are zero.
The Heisenberg Uncertainty Principle and the Nyquist-Shannon Sampling Theorem
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Millette P. A.
2013-07-01
Full Text Available The derivation of the Heisenberg Uncertainty Principle (HUP from the Uncertainty Theorem of Fourier Transform theory demonstrates that the HUP arises from the dependency of momentum on a wave number that exists at the quantum level. It also establishes that the HUP is purely a relationship between the eﬀective widths of Fourier transform pairs of variables (i.e. conjugate variables. We note that the HUP is not a quantum mechanical measurement principle per se. We introduce the Quantum Mechanical equivalent of the Nyquist-Shannon Sampling Theorem of Fourier Transform theory, and show that it is a better principle to describe the measurement limitations of Quantum Mechanics. We show that Brillouin zones in Solid State Physics are a manifestation of the Nyquist-Shannon Sampling Theorem at the quantum level. By comparison with other ﬁelds where Fourier Transform theory is used, we propose that we need todiscern between measurement limitations and inherent limitations when interpreting the impact of the HUP on the nature of the quantum level. We further propose that while measurement limitations result in our perception of indeterminism at the quantum level, there is no evidence that there are any inherent limitations at the quantum level, based on the Nyquist-Shannon Sampling Theorem
March, N. H.; Klein, D. J.
The Ising model in low dimensions is used for ferromagnets to relate internal energy and entropy to the magnetization. While this is done throughout the ferromagnetic phase, the low temperature predictions are compared with microscopic elementary excitations theory for both insulating and metallic ferromagnets. The model predictions are oversimplified. The spin s=1/2 Heisenberg model for an insulating antiferromagnet is then considered, starting from one dimension and building up a two-dimensional square lattice from lattice strips of variable width. Chemical approaches based an counting local spin-pairing patterns (or Kekulé structures) are brought into contact with recent work on ladders, with both even and odd numbers of legs, in the context of high-T c cuprates. Finally, the Hubbard model and the closely related t-J model are discussed. For the former, simple rules, again based on a chemical approach, are proposed for predicting the spin properties of the ground states and comparison is made with existing computer studies. The related t-J model is briefly considered in relation to carriers moving through antiferromagnetic assemblies as in the high-T c materials.
On foundational thinking in fundamental physics, from Riemann to Einstein to Heisenberg
Plotnitsky, Arkady
2012-03-01
This paper considers the nature of foundational thinking in fundamental physics, most especially in quantum mechanics. By "fundamental physics" I mean those areas of experimental and theoretical physics that deal with the ultimate constitution of nature, for example, as defined by the so-called elementary particles in the case of quantum physics. By "foundational thinking" I mean thinking that concerns fundamental physics itself. First, I argue, following Riemann, that our foundational thinking is based on hypotheses that we form and test. Second, I argue that foundational thinking in physics is defined by concepts, and that in modern physics foundational concepts always contains physical, mathematical, and philosophical components. Third, finally, I argue that the relationships between these components and, hence, our foundational thinking, are different in quantum mechanics than they are in classical physics and relativity. In these theories mathematics describes, by way of idealized models, physical reality, and predictions made by them are derived from these descriptions. By contrast, in quantum mechanics, mathematics only serves to predict the outcome of quantum experiments in the absence of any description, however idealized, of quantum objects and their behavior. At least such is the case in certain interpretations of quantum mechanics, which follow and develop Heisenberg's approach in his paper introducing quantum mechanics, as does, for example, Bohr's interpretation, known as complementarity.
Quantum-Wave Equation and Heisenberg Inequalities of Covariant Quantum Gravity
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Claudio Cremaschini
2017-07-01
Full Text Available Key aspects of the manifestly-covariant theory of quantum gravity (Cremaschini and Tessarotto 2015–2017 are investigated. These refer, first, to the establishment of the four-scalar, manifestly-covariant evolution quantum wave equation, denoted as covariant quantum gravity (CQG wave equation, which advances the quantum state ψ associated with a prescribed background space-time. In this paper, the CQG-wave equation is proved to follow at once by means of a Hamilton–Jacobi quantization of the classical variational tensor field g ≡ g μ ν and its conjugate momentum, referred to as (canonical g-quantization. The same equation is also shown to be variational and to follow from a synchronous variational principle identified here with the quantum Hamilton variational principle. The corresponding quantum hydrodynamic equations are then obtained upon introducing the Madelung representation for ψ , which provides an equivalent statistical interpretation of the CQG-wave equation. Finally, the quantum state ψ is proven to fulfill generalized Heisenberg inequalities, relating the statistical measurement errors of quantum observables. These are shown to be represented in terms of the standard deviations of the metric tensor g ≡ g μ ν and its quantum conjugate momentum operator.
Multiloop Euler-Heisenberg Lagrangians, Schwinger Pair Creation, and the Photon S-Matrix
Huet, I.; de Traubenberg, M. R.; Schubert, C.
2017-03-01
Although the perturbation series in quantum electrodynamics has been studied for eighty years concerning its high-order behavior, our present understanding is still poorer than for many other field theories. An interesting case is Schwinger pair creation in a constant electric field, which may possibly provide a window to high loop orders; simple non-perturbative closed-form expressions have been conjectured for the pair creation rate in the weak field limit, for scalar QED in 1982 by Affleck, Alvarez, and Manton, and for spinor QED by Lebedev and Ritus in 1984. Using Borel analysis, these can be used to obtain non-perturbative information on the on-shell renormalized N-photon amplitudes at large N and low energy. This line of reasoning also leads to a number of nontrivial predictions for the effective QED Lagrangian in either four or two dimensions at any loop order, and preliminary results of a calculation of the three-loop Euler-Heisenberg Lagrangian in two dimensions are presented.
Ground state properties of the bond alternating spin-1/2 anisotropic Heisenberg chain
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S. Paul
2017-06-01
Full Text Available Ground state properties, dispersion relations and scaling behaviour of spin gap of a bond alternating spin-1/2 anisotropic Heisenberg chain have been studied where the exchange interactions on alternate bonds are ferromagnetic (FM and antiferromagnetic (AFM in two separate cases. The resulting models separately represent nearest neighbour (NN AFM-AFM and AFM-FM bond alternating chains. Ground state energy has been estimated analytically by using both bond operator and Jordan-Wigner representations and numerically by using exact diagonalization. Dispersion relations, spin gap and several ground state orders have been obtained. Dimer order and string orders are found to coexist in the ground state. Spin gap is found to develop as soon as the non-uniformity in alternating bond strength is introduced in the AFM-AFM chain which further remains non-zero for the AFM-FM chain. This spin gap along with the string orders attribute to the Haldane phase. The Haldane phase is found to exist in most of the anisotropic region similar to the isotropic point.
NMR evidence for peculiar spin gaps in a doped S=1/2 Heisenberg spin chain
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Utz, Yannic; Rudisch, Christian; Hammerath, Franziska; Grafe, Hans-Joachim; Mohan, Ashwin; Ribeiro, Patrick; Hess, Christian; Wolter, Anja; Kataev, Vladislav; Nishimoto, Satoshi; Drechsler, Stefan-Ludwig; Buechner, Bernd [IFW Dresden (Germany); Singh, Surjeet [Indian Institute of Science Education and Research, Pune (India); Saint-Martin, Romuald; Revcolevschi, Alexandre [Laboratoire de Physico-Chimie de l' Etat Solide, Universite Paris-Sud, Orsay (France)
2012-07-01
We present {sup 63}Cu Nuclear Magnetic Resonance (NMR) measurements on undoped, Ca-doped and Ni-doped SrCuO{sub 2} single crystals. SrCuO{sub 2} is a good realization of a one-dimensional S=1/2 Heisenberg spin chain. This is manifested by the theoretically-expected temperature-independent NMR spin-lattice relaxation rate T{sub 1}{sup -1}. In Sr{sub 0.9}Ca{sub 0.1}CuO{sub 2} an exponential decrease of T{sub 1}{sup -1} below 90 K evidences the opening of a gap in the spin excitation spectrum, which amounts to {Delta}=50 K. DMRG calculations are presented to discuss the origin of this spin gap. New results on SrCu{sub 0.99}Ni{sub 0.01}O{sub 2} also indicate the presence of a spin gap, which is twice as large as in Sr{sub 0.9}Ca{sub 0.1}CuO{sub 2}, despite the minor doping level of Ni compared to Ca. We discuss different possible impacts of Ca (S=0) and Ni (S=1) doping on structural and magnetic properties of the parent compound.
Investigation of the chiral antiferromagnetic Heisenberg model using projected entangled pair states
Poilblanc, Didier
2017-09-01
A simple spin-1/2 frustrated antiferromagnetic Heisenberg model (AFHM) on the square lattice—including chiral plaquette cyclic terms—was argued [A. E. B. Nielsen, G. Sierra, and J. I. Cirac, Nat. Commun. 4, 2864 (2013), 10.1038/ncomms3864] to host a bosonic Kalmeyer-Laughlin (KL) fractional quantum Hall ground state [V. Kalmeyer and R. B. Laughlin, Phys. Rev. Lett. 59, 2095 (1987), 10.1103/PhysRevLett.59.2095]. Here, we construct generic families of chiral projected entangled pair states (chiral PEPS) with low bond dimension (D =3 ,4 ,5 ) which, upon optimization, provide better variational energies than the KL Ansatz. The optimal D =3 PEPS exhibits chiral edge modes described by the Wess-Zumino-Witten SU(2) 1 model, as expected for the KL spin liquid. However, we find evidence that, in contrast to the KL state, the PEPS spin liquids have power-law dimer-dimer correlations and exhibit a gossamer long-range tail in the spin-spin correlations. We conjecture that these features are genuine to local chiral AFHM on bipartite lattices.
La{sub 2}NiTiO{sub 6}: A 3D S=1 fcc Heisenberg antiferromagnet
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Karolak, Michael; Edelmann, Martin; Sangiovanni, Giorgio [Institut fuer Theoretische Physik und Astrophysik, Universitaet Wuerzburg (Germany)
2015-07-01
A DFT+DMFT analysis of the double perovskite La{sub 2}NiTiO{sub 6} reveals the crystal to exhibit a nearly unfrustrated three-dimensional ordering of local magnetic moments of S=1 on an fcc sublattice. In DFT, La{sub 2}NiTiO{sub 6} shows a peculiar bandstructure in which the Ni e{sub g} bands are half-filled and split from bands of other character by at least 0.5 eV. The bandwidth of Ni e{sub g} is around 0.8 eV, which is attributed to strongly reduced hopping amplitudes caused by the Ti sites. By Wannier projection on the correlated subspace of only Ni e{sub g}, an effective direct exchange model is derived to obtain quantitative values for the superexchange coupling between Ni sites. Comparing nearest-neighbour to next-nearest-neighbour coupling, the latter exceeds the former by a factor of 4 at minimum. This causes a nearly unfrustrated antiferromagnetic ordering of the local moments, whose Neel temperature is low not as a result of frustration but of strong correlation, as is revealed by an investigation of the kinetic and potential energy differences between ordered an unordered phase. The double perovskite La{sub 2}NiTiO{sub 6} is identified as an interesting S=1 quantum antiferromagnet on a three-dimensional fcc sublattice. By means of Density Functional Theory (DFT) in combination with Dynamical Mean Field Theory (DMFT) it is demonstrated that this material is a high-spin d-electron system deep in the Heisenberg limit and established that its paramagnetic Mott phase persists down to low temperatures not because of frustration effects but rather for the strong coupling physics. Our many-body calculations on an ab initio-derived multi-orbital basis predict indeed a kinetic energy gain when entering the magnetically ordered phase. The strong-coupling nature is assessed from a multi-orbital DFT+DMFT analysis of the energetic balance between the ordered and disordered phase, which reveals a kinetic-energy-driven ordering. La{sub 2}NiTiO{sub 6} emerges thus as a
Palacios-Gimenez, Octavio M; Milani, Diogo; Lemos, Bernardo; Castillo, Elio R; Martí, Dardo A; Ramos, Erica; Martins, Cesar; Cabral-de-Mello, Diogo C
2018-01-08
Neo-sex chromosome systems arose independently multiple times in evolution, presenting the remarkable characteristic of repetitive DNAs accumulation. Among grasshoppers, occurrence of neo-XY was repeatedly noticed in Melanoplinae. Here we analyzed the most abundant tandem repeats of R. bergii (2n = 22, neo-XY♂) using deep Illumina sequencing and graph-based clustering in order to address the neo-sex chromosomes evolution. The analyses revealed ten families of satDNAs comprising about ~1% of the male genome, which occupied mainly C-positive regions of autosomes. Regarding the sex chromosomes, satDNAs were recorded within centromeric or interstitial regions of the neo-X chromosome and four satDNAs occurred in the neo-Y, two of them being exclusive (Rber248 and Rber299). Using a combination of probes we uncovered five well-defined cytological variants for neo-Y, originated by multiple paracentric inversions and satDNA amplification, besides fragmented neo-Y. These neo-Y variants were distinct in frequency between embryos and adult males. The genomic data together with cytogenetic mapping enabled us to better understand the neo-sex chromosome dynamics in grasshoppers, reinforcing differentiation of neo-X and neo-Y and revealing the occurrence of multiple additional rearrangements involved in the neo-Y evolution of R. bergii. We discussed the possible causes that led to differences in frequency for the neo-Y variants between embryos and adults. Finally we hypothesize about the role of DNA satellites in R. bergii as well as putative historical events involved in the evolution of the R. bergii neo-XY.
Zhu, Jia-Qiao; Tan, Seang Lin; Taketo, Teruko
2017-04-19
The B6.YTIR (XY) mouse develops bilateral ovaries despite the expression of the testis-determining gene Sry during gonadal differentiation. We reported that the oocytes of the XY female are defective in their cytoplasm, resulting in a failure in the second meiotic division after activation or fertilization in vitro. However, the mechanism of meiotic failure or the cause of infertility remained to be clarified. In the present study, we obtained mature oocytes from XY females by superovulation and confirmed that these oocytes also fail in zygotic development. By using confocal microscopy 3D-analysis, we demonstrated that meiotic spindles were properly positioned and oriented in the MII-oocytes from XY females. After parthenogenic activation, fewer oocytes from XY females extruded the second polar body, and in those oocytes, sister-chromatids were often separated but neither set entered the second polar body. ARP2, F-actin, and ORC4, known to play roles in asymmetric meiotic division, were initially localized along the ooplasmic membrane and concentrated over the MII-spindle but lost their cortical polarity after activation while the sister-chromatids moved away from the oolemma in the oocytes from XY females. Our results indicate that the second polar body extrusion is uncoupled from the sister-chromatids separation in the oocytes from XY female mouse.
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Strečka, Jozef, E-mail: jozef.strecka@upjs.sk [Department of Theoretical Physics and Astrophysics, Faculty of Science, P.J. Šafárik University, Park Angelinum 9, 040 01 Košice (Slovakia); Alécio, Raphael Cavalcante; Lyra, Marcelo L. [Instituto de Física, Universidade Federal de Alagoas, 57072-970 Maceio-AL (Brazil); Rojas, Onofre [Departamento de Física, Universidade Federal de Lavras, 37200-000 Lavras-MG (Brazil)
2016-07-01
The spin-1/2 Ising–Heisenberg three-leg tube composed of the Heisenberg spin triangles mutually coupled through the Ising inter-triangle interaction is exactly solved in a zero magnetic field. By making use of the local conservation for the total spin on each Heisenberg spin triangle the model can be rigorously mapped onto a classical composite spin-chain model, which is subsequently exactly treated through the transfer-matrix method. The ground-state phase diagram, correlation functions, concurrence, Bell function, entropy and specific heat are examined in detail. It is shown that the spin frustration represents an indispensable ground for a thermal entanglement, which is quantified by the quantum concurrence. The specific heat displays diverse temperature dependences, which may include a sharp low-temperature peak mimicking a temperature-driven first-order phase transition. It is convincingly evidenced that this anomalous peak originates from massive thermal excitations from the doubly degenerate ground state towards an excited state with a high macroscopic degeneracy due to chiral degrees of freedom of the Heisenberg spin triangles. - Highlights: • Spin-1/2 Ising–Heisenberg three-leg tube is exactly solved in a zero magnetic field. • Thermal entanglement is only present in a frustrated part of the parameter space. • Spin frustration and thermal entanglement show antagonistic reentrance. • Specific heat may display a sharp narrow peak due to massive thermal excitations.
Thermal Entanglement in a Three-Qubit Quantum System with DM Interaction
Li, Jianping
2017-03-01
Entanglement properties of Heisenberg spin chain has received much attention in the context of quantum information. The generation and the manipulation of entangled states especially thermal entanglement have been extensively studied in the Heisenberg models. In this article, we studied the thermal entanglement in a three-qubit spin system. It is found that the DM interaction along the Z axis can give rise to a thermal entanglement.
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Zimmerman Peter A
2010-06-01
Full Text Available Abstract Background Diagnosis of infectious diseases now benefits from advancing technology to perform multiplex analysis of a growing number of variables. These advances enable simultaneous surveillance of markers characterizing species and strain complexity, mutations associated with drug susceptibility, and antigen-based polymorphisms in relation to evaluation of vaccine effectiveness. We have recently developed assays detecting single nucleotide polymorphisms (SNPs in the P. falciparum genome that take advantage of post-PCR ligation detection reaction and fluorescent microsphere labeling strategies. Data from these assays produce a spectrum of outcomes showing that infections result from single to multiple strains. Traditional methods for distinguishing true positive signal from background can cause false positive diagnoses leading to incorrect interpretation of outcomes associated with disease treatment. Results Following analysis of Plasmodium falciparum dihydrofolate reductase SNPs associated with resistance to a commonly used antimalarial drug, Fansidar (Sulfadoxine/pyrimethamine, and presumably neutral SNPs for parasite strain differentiation, we first evaluated our data after setting a background signal based on the mean plus three standard deviations for known negative control samples. Our analysis of single allelic controls suggested that background for the absent allele increased as the concentration of the target allele increased. To address this problem, we introduced a simple change of variables from customary (X,Y (Cartesian coordinates to planar polar coordinates (X = rcos(θ, Y = rsin(θ. Classification of multidimensional fluorescence signals based on histograms of angular and radial data distributions proved more effective than classification based on Cartesian thresholds. Comparison with known diallelic dilution controls suggests that histogram-based classification is effective for major:minor allele concentration ratios as
Directory of Open Access Journals (Sweden)
Y. V. Tymoshenko
2017-11-01
Full Text Available Low-energy spin excitations in any long-range ordered magnetic system in the absence of magnetocrystalline anisotropy are gapless Goldstone modes emanating from the ordering wave vectors. In helimagnets, these modes hybridize into the so-called helimagnon excitations. Here we employ neutron spectroscopy supported by theoretical calculations to investigate the magnetic excitation spectrum of the isotropic Heisenberg helimagnet ZnCr_{2}Se_{4} with a cubic spinel structure, in which spin-3/2 magnetic Cr^{3+} ions are arranged in a geometrically frustrated pyrochlore sublattice. Apart from the conventional Goldstone mode emanating from the (0 0 q_{h} ordering vector, low-energy magnetic excitations in the single-domain proper-screw spiral phase show soft helimagnon modes with a small energy gap of ∼0.17 meV, emerging from two orthogonal wave vectors (q_{h} 0 0 and (0 q_{h} 0 where no magnetic Bragg peaks are present. We term them pseudo-Goldstone magnons, as they appear gapless within linear spin-wave theory and only acquire a finite gap due to higher-order quantum-fluctuation corrections. Our results are likely universal for a broad class of symmetric helimagnets, opening up a new way of studying weak magnon-magnon interactions with accessible spectroscopic methods.
Energy Technology Data Exchange (ETDEWEB)
Utz, Yannic; Hammerath, Franziska; Nishimoto, Satoshi; Drechsler, Stefan-Ludwig; Hess, Christian; Buechner, Bernd; Grafe, Hans-Joachim [IFW Dresden (Germany); Beesetty, Neela Sekhar; Saint-Martin, Romuald; Revcolevschi, Alexandre [SP2M-ICMMO UMR-CNRS, Universite Paris-Sud (France)
2015-07-01
We present {sup 63}Cu NMR measurements on single crystals of Sr{sub 2}CuO{sub 3} doped with different amounts of nickel and compare them to numerical DMRG results. The parent compound contains copper-oxygen chains with S=1/2 on the copper site coupled by a large antiferromagnetic exchange coupling J ∼ 2000 K and is known to be a good realization of the 1D Heisenberg model. The measurements show that replacing only a few of the S=1/2 Cu ions with S=1 Ni has a major impact on the magnetic properties of the spin chain system. An unusual line broadening in the low temperature NMR spectra reveals the existence of an impurity-induced local alternating magnetization (LAM), and exponentially decaying spin-lattice relaxation rates T{sup -1}{sub 1} towards low temperatures indicate the opening of a spin gap similar to Ca-doped Sr{sub 2}CuO{sub 3}. While the T{sup -1}{sub 1} measurements could be explained by pure chain segmentation, as expected for a S=0 impurity, the spectra can only be understood by taking the nickel.
Energy Technology Data Exchange (ETDEWEB)
Zhang, Lei; Navrotsky, Alexandra, E-mail: anavrotsky@ucdavis.edu
2015-10-15
Lanthanum, yttrium, and neodymium doped uranium dioxide samples in the fluorite structure have been synthesized, characterized in terms of metal ratio and oxygen content, and their enthalpies of formation measured by high temperature oxide melt solution calorimetry. For oxides doped with 10–50 mol % rare earth (Ln) cations, the formation enthalpies from constituent oxides (LnO{sub 1.5}, UO{sub 2} and UO{sub 3} in a reaction not involving oxidation or reduction) become increasingly exothermic with increasing rare earth content, while showing no significant dependence on the varying uranium oxidation state. The oxidation enthalpy of Ln{sub x}U{sub 1−x}O{sub 2−0.5x+y} is similar to that of UO{sub 2} to UO{sub 3} for all three rare earth doped systems. Though this may suggest that the oxidized uranium in these systems is energetically similar to that in the hexavalent state, thermochemical data alone can not constrain whether the uranium is present as U{sup 5+}, U{sup 6+}, or a mixture of oxidation states. The formation enthalpies from elements calculated from the calorimetric data are generally consistent with those from free energy measurements. - Highlights: • We synthesize, characterize Ln{sub x}U{sub 1−x}O{sub 2−0.5x+y} solid solutions (Ln = La, Y, Nd). • Formation enthalpies become more exothermic with increasing rare earth content. • Oxidation enthalpy of Ln{sub x}U{sub 1−x}O{sub 2−0.5x+y} is similar to that of UO{sub 2} to UO{sub 3}. • Direct calorimetric measurements are in good agreement with free energy data.
A Novel SRY Gene Mutation p.F109L in a 46,XY Female with Complete Gonadal Dysgenesis.
Andonova, Silvia; Robeva, Ralitsa; Sirakov, Milko; Mainhard, Karela; Tomova, Analia; Ledig, Susanne; Kumanov, Philip; Savov, Alexey
2015-01-01
46,XY complete gonadal dysgenesis (CGD) is a disorder of sexual development that can result from different mutations in genes associated with sex determination. Patients are phenotypically females, and the disease is often diagnosed in late adolescence because of delayed puberty. Here, we present the clinical and molecular data of a 46,XY female CGD patient with gonadoblastoma with dysgerminoma and incidentally found inherited thrombophilia. The clinical significance of the described de novo SRY gene mutation c.325T>C (p.F109L) is discussed. This case report supports the critical role of the HGM domain in the SRY gene and the need of a multidisciplinary approach for CGD patients. © 2016 S. Karger AG, Basel.
Chauhan, V; Dada, R; Jain, V
2017-11-01
Retraction: 'Aetiology and clinical profile of children with 46, XY differences of sex development at an Indian referral centre' by Vasundhera Chauhan, Rima Dada, Vandana Jain The above article, published online on 8 August 2016 in Wiley Online Library (http://wileyonlinelibrary.com), has been retracted by agreement between the authors, the Journal Editors-in-Chief, Wolf-Bernhard Schill and Ralf Henkel, and Blackwell Verlag GmbH. The retraction has been agreed as the result of an unresolved dispute between the first author and a colleague research fellow due to the inclusion of data from patients who were simultaneously enrolled in two studies being conducted separately by the two parties. Reference Chauhan, V., Dada, R. and Jain, V. (2016), Aetiology and clinical profile of children with 46, XY differences of sex development at an Indian referral centre. Andrologia. doi:10.1111/and.12663. © 2016 Blackwell Verlag GmbH.
Traut, W; Wollert, B
1998-04-01
The sex chromosomes of the Megaselia scalaris wild-type strain Wien are homomorphic. We studied a roughly 1.8 kb X/Y DNA segment of this strain. It includes, at one end, the first part of a coding sequence for a protein of the vespid antigen 5 family. Molecular differentiation between the X and Y chromosomes has commenced, but homology, even of short DNA stretches, is still assessable beyond doubt. The most conspicuous differences between the X and the homologous Y segment were insertions/deletions in the noncoding region: among them, deletions, a duplication, and an insertion of a mobile element. These structural changes grossly disrupted homology. In comparison, base substitutions, though more numerous, contributed little to the differentiation of the X/Y DNA segment.
Strečka, Jozef; Ekiz, Cesur
2015-05-01
The geometrically frustrated spin-1/2 Ising-Heisenberg model on triangulated Husimi lattices is exactly solved by combining the generalized star-triangle transformation with the method of exact recursion relations. The ground-state and finite-temperature phase diagrams are rigorously calculated along with both sublattice magnetizations of the Ising and Heisenberg spins. It is evidenced that the Ising-Heisenberg model on triangulated Husimi lattices with two or three interconnected triangles-in-triangles units displays in a highly frustrated region a quantum disorder irrespective of temperature, whereas the same model on triangulated Husimi lattices with a greater connectivity of triangles-in-triangles units exhibits at low enough temperatures an outstanding quantum order due to the order-by-disorder mechanism. The quantum reduction of both sublattice magnetizations in the peculiar quantum ordered state gradually diminishes upon increasing the coordination number of the underlying Husimi lattice.
Mitsuhashi, Tomoko; Warita, Katsuhiko; Tabuchi, Yoshiaki; Takasaki, Ichiro; Kondo, Takashi; Sugawara, Teruo; Hayashi, Fumio; Wang, Zhi-Yu; Matsumoto, Yoshiki; Miki, Takanori; Takeuchi, Yoshiki; Ebina, Yasuhiko; Yamada, Hideto; Sakuragi, Noriaki; Yokoyama, Toshifumi; Nanmori, Takashi; Kitagawa, Hiroshi; Kant, Jeffrey A; Hoshi, Nobuhiko
2010-03-01
XY females are rare individuals who carry a Y chromosome but are phenotypically female. In approximately 80-90% of these cases, there are no mutations in the SRY gene, a testis-determining gene on the short arm of the Y chromosome, and the pathophysiology of XY females without SRY mutation remains unclear. In the present study, we used a molecular data mining technique to analyze the pathophysiology of an XY female with functional SRY and pericentric inversion of the Y chromosome, and compared the results with those of a normal male. Interestingly, upregulations of numerous genes included in the development category of the Biological Process ontology, including genes associated with sex determination and organ morphogenesis, were seen in the patient. Additionally, the transforming growth factor-beta (TGF-beta) signaling pathway and Wnt signaling pathway, in which most cell-cell interactions during embryonic development are involved, were altered. Alterations in the expression of numerous genes at the developmental stage, including alterations at both the gene and pathway levels, may persist as a vestige of anomalies of sex differentiation that presumably began in the fetal period. The present study indicates that a data mining technique using bioinformatics contributes to identification of not only genes responsible for birth defects, but also disorders of sex development (DSD)-specific pathways, and that this kind of analysis is an important tool for clarifying the pathophysiology of human idiopathic XY gonadal dysgenesis. Our findings could serve as one of the basic datasets which will be used for future follow-up investigations.
Novel candidate genes for 46,XY gonadal dysgenesis identified by a customized 1 M array-CGH platform
Norling, Ameli; Lindén Hirschberg, Angelica; Iwarsson, Erik; Persson, Bengt; Wedell, Anna; Barbaro, Michela
2013-01-01
Half of all patients with a disorder of sex development (DSD) do not receive a specific molecular diagnosis. Comparative genomic hybridization (CGH) can detect copy number changes causing gene haploinsufficiency or over-expression that can lead to impaired gonadal development and gonadal DSD. The purpose of this study was to identify novel candidate genes for 46,XY gonadal dysgenesis (GD) using a customized 1 M array-CGH platform with whole-genome coverage and probe enrichment targeting 78 ge...
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J. Strečka
2012-12-01
Full Text Available The spin-1/2 Ising-Heisenberg model on diamond-like decorated Bethe lattices is exactly solved in the presence of the longitudinal magnetic field by combining the decoration-iteration mapping transformation with the method of exact recursion relations. In particular, the ground state and low-temperature magnetization process of the ferrimagnetic version of the considered model is investigated in detail. Three different magnetization scenarios with up to two consecutive fractional magnetization plateaus were found, whereas the intermediate magnetization plateau may either correspond to the classical ferrimagnetic spin arrangement and/or the field-induced quantum ferrimagnetic spin ordering without any classical counterpart.
Luo, Mengcheng; Zhou, Jian; Leu, N. Adrian; Abreu, Carla M.; Wang, Jianle; Anguera, Montserrat C.; de Rooij, Dirk G.; Jasin, Maria; Wang, P. Jeremy
2015-01-01
Polycomb group proteins mediate transcriptional silencing in diverse developmental processes. Sex chromosomes undergo chromosome-wide transcription silencing during male meiosis. Here we report that mouse SCML2 (Sex comb on midleg-like 2), an X chromosome-encoded polycomb protein, is specifically expressed in germ cells, including spermatogonia, spermatocytes, and round spermatids. SCML2 associates with phosphorylated H2AX and localizes to the XY body in spermatocytes. Loss of SCML2 in mice causes defective spermatogenesis, resulting in sharply reduced sperm production. SCML2 interacts with and recruits a deubiquitinase, USP7, to the XY body in spermatocytes. In the absence of SCML2, USP7 fails to accumulate on the XY body, whereas H2A monoubiquitination is dramatically augmented in the XY chromatin. Our results demonstrate that the SCML2/USP7 complex constitutes a novel molecular pathway in modulating the epigenetic state of sex chromosomes during male meiosis. PMID:25634095
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Amy B. Wisniewski
2012-01-01
Full Text Available Variables that impact gender development in humans are difficult to evaluate. This difficulty exists because it is not usually possible to tease apart biological influences on gender from social variables. People with disorders of sex development, or DSD, provide important opportunities to study gender within individuals for whom biologic components of sex can be discordant with social components of gender. While most studies of gender development in people with 46,XY DSD have historically emphasized the importance of genes and hormones on gender identity and gender role, more recent evidence for a significant role for socialization exists and is considered here. For example, the influence of parents’ perceptions of, and reactions to, DSD are considered. Additionally, the impact of treatments for DSD such as receiving gonadal surgeries or genitoplasty to reduce genital ambiguity on the psychological development of people with 46,XY DSD is presented. Finally, the role of multi-disciplinary care including access to peer support for advancing medical, surgical and psychosexual outcomes of children and adults with 46,XY DSD, regardless of sex of rearing, is discussed.
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Christophe Dufresnes
Full Text Available In contrast with mammals and birds, most poikilothermic vertebrates feature structurally undifferentiated sex chromosomes, which may result either from frequent turnovers, or from occasional events of XY recombination. The latter mechanism was recently suggested to be responsible for sex-chromosome homomorphy in European tree frogs (Hyla arborea. However, no single case of male recombination has been identified in large-scale laboratory crosses, and populations from NW Europe consistently display sex-specific allelic frequencies with male-diagnostic alleles, suggesting the absence of recombination in their recent history. To address this apparent paradox, we extended the phylogeographic scope of investigations, by analyzing the sequences of three sex-linked markers throughout the whole species distribution. Refugial populations (southern Balkans and Adriatic coast show a mix of X and Y alleles in haplotypic networks, and no more within-individual pairwise nucleotide differences in males than in females, testifying to recurrent XY recombination. In contrast, populations of NW Europe, which originated from a recent postglacial expansion, show a clear pattern of XY differentiation; the X and Y gametologs of the sex-linked gene Med15 present different alleles, likely fixed by drift on the front wave of expansions, and kept differentiated since. Our results support the view that sex-chromosome homomorphy in H. arborea is maintained by occasional or historical events of recombination; whether the frequency of these events indeed differs between populations remains to be clarified.
Dufresnes, Christophe; Stöck, Matthias; Brelsford, Alan; Perrin, Nicolas
2014-01-01
In contrast with mammals and birds, most poikilothermic vertebrates feature structurally undifferentiated sex chromosomes, which may result either from frequent turnovers, or from occasional events of XY recombination. The latter mechanism was recently suggested to be responsible for sex-chromosome homomorphy in European tree frogs (Hyla arborea). However, no single case of male recombination has been identified in large-scale laboratory crosses, and populations from NW Europe consistently display sex-specific allelic frequencies with male-diagnostic alleles, suggesting the absence of recombination in their recent history. To address this apparent paradox, we extended the phylogeographic scope of investigations, by analyzing the sequences of three sex-linked markers throughout the whole species distribution. Refugial populations (southern Balkans and Adriatic coast) show a mix of X and Y alleles in haplotypic networks, and no more within-individual pairwise nucleotide differences in males than in females, testifying to recurrent XY recombination. In contrast, populations of NW Europe, which originated from a recent postglacial expansion, show a clear pattern of XY differentiation; the X and Y gametologs of the sex-linked gene Med15 present different alleles, likely fixed by drift on the front wave of expansions, and kept differentiated since. Our results support the view that sex-chromosome homomorphy in H. arborea is maintained by occasional or historical events of recombination; whether the frequency of these events indeed differs between populations remains to be clarified.
Novel Insights into 46,XY Disorders of Sex Development due to NR5A1 Gene Mutation.
Werner, Ralf; Mönig, Isabel; August, Julia; Freiberg, Clemens; Lünstedt, Ralf; Reiz, Benedikt; Wünsch, Lutz; Holterhus, Paul-Martin; Kulle, Alexandra; Döhnert, Ulla; Wudy, Stefan A; Richter-Unruh, Annette; Thorns, Christoph; Hiort, Olaf
2015-01-01
The differential diagnosis of 46,XY disorders of sex development (DSD) is based on the distinction between forms of gonadal dysgenesis and disorders of androgen biosynthesis and action. However, clinical and endocrine evaluations are often not conclusive. Here, we describe an adolescent female with hirsutism and hyperandrogenization at puberty. Her karyotype was 46,XY, and clinical investigation demonstrated clitoromegaly, but no uterine remnants were detected. Histology of the gonads revealed a testicular structure with a Sertoli-cell-only pattern. Endocrine evaluation showed hypergonadotropic hypogonadism, and the Sertoli cell markers inhibin B and anti-Müllerian hormone were also low. Several molecular genetic studies were initiated. While analyses of the androgen receptor gene, the SRD5A2 gene and HSD17B3 gene were uninformative, a novel p.L230R mutation was found in the NR5A1 gene. A mutant construct proved a severe dysfunction of this variant in functional analysis after recreation and transfection into HeLa cells. We conclude that the NR5A1 p.L230R mutation most likely leads to a spatial and time-dependent Leydig cell and Sertoli cell dysfunction during development not causing the classical gonadal dysgenesis phenotype. This case demonstrates that the current classification should be updated to encompass the overlapping phenotypes of some genetic conditions within 46,XY DSD. © 2015 S. Karger AG, Basel.
Wisniewski, Amy B.
2012-01-01
Variables that impact gender development in humans are difficult to evaluate. This difficulty exists because it is not usually possible to tease apart biological influences on gender from social variables. People with disorders of sex development, or DSD, provide important opportunities to study gender within individuals for whom biologic components of sex can be discordant with social components of gender. While most studies of gender development in people with 46,XY DSD have historically emphasized the importance of genes and hormones on gender identity and gender role, more recent evidence for a significant role for socialization exists and is considered here. For example, the influence of parents' perceptions of, and reactions to, DSD are considered. Additionally, the impact of treatments for DSD such as receiving gonadal surgeries or genitoplasty to reduce genital ambiguity on the psychological development of people with 46,XY DSD is presented. Finally, the role of multi-disciplinary care including access to peer support for advancing medical, surgical and psychosexual outcomes of children and adults with 46,XY DSD, regardless of sex of rearing, is discussed. PMID:24278745
Novel mutations of HSD17B3 in three Chinese patients with 46,XY Disorders of Sex Development.
Yu, Bingqing; Liu, Zhaoxiang; Mao, Jiangfeng; Wang, Xi; Zheng, Junjie; Xiong, Shuyu; Cui, Mingxuan; Ma, Wanlu; Huang, Qibin; Xu, Hongli; Huang, Bingkun; Nie, Min; Wu, Xueyan
2017-10-01
17β-Hydroxysteroid dehydrogenase type 3 (17β-HSD3) converts the inactive Δ4-androstenedione (A) to testosterone (T). Its deficiency is the most common testosterone biosynthesis defect that results in 46,XY Disorders Of Sex Development (DSD). However, the disease is difficult to distinguish from other 46,XY DSD for similar clinical phenotypes. Therefore, genetic testing provides good criteria for the diagnosis of the disease. In this study, HSD17B3 gene was examined in 3 unrelated Chinese patients with 46,XY DSD. Direct sequencing and quantitative PCR of HSD17B3 gene revealed the presence of a compound heterozygous mutation (p.I60T/exon1 deletion) in Patient 1, a homozygous (p.I60T) mutation in Patient 2 and a frameshift mutation (p.V25Efs∗54) and an exon1 deletion in Patient 3. All of the mutations have not been reported previously. These novel mutations may expand the mutation database of HSD17B3 gene and provide us new insights into the molecular mechanism of 17β-HSD3 deficiency. It is noteworthy that when direct sequence analysis showed a rare homozygous mutation in patients with non-consanguineous parents, "apparent homozygosity" should be taken into an account and the intragenic deletion should be screened. In addition, when single mutation was found in patients with disease in recessive heredity mode, the intragenic deletion should also be screened. Copyright © 2017 Elsevier Inc. All rights reserved.
Correa, Stephanie M; Washburn, Linda L; Kahlon, Ravi S; Musson, Michelle C; Bouma, Gerrit J; Eicher, Eva M; Albrecht, Kenneth H
2012-01-01
Sex reversal can occur in XY humans with only a single functional WT1 or SF1 allele or a duplication of the chromosome region containing WNT4. In contrast, XY mice with only a single functional Wt1, Sf1, or Wnt4 allele, or mice that over-express Wnt4 from a transgene, reportedly are not sex-reversed. Because genetic background plays a critical role in testis differentiation, particularly in C57BL/6J (B6) mice, we tested the hypothesis that Wt1, Sf1, and Wnt4 are dosage sensitive in B6 XY mice. We found that reduced Wt1 or Sf1 dosage in B6 XY(B6) mice impaired testis differentiation, but no ovarian tissue developed. If, however, a Y(AKR) chromosome replaced the Y(B6) chromosome, these otherwise genetically identical B6 XY mice developed ovarian tissue. In contrast, reduced Wnt4 dosage increased the amount of testicular tissue present in Sf1+/- B6 XY(AKR), Wt1+/- B6 XY(AKR), B6 XY(POS), and B6 XY(AKR) fetuses. We propose that Wt1(B6) and Sf1(B6) are hypomorphic alleles of testis-determining pathway genes and that Wnt4(B6) is a hypermorphic allele of an ovary-determining pathway gene. The latter hypothesis is supported by the finding that expression of Wnt4 and four other genes in the ovary-determining pathway are elevated in normal B6 XX E12.5 ovaries. We propose that B6 mice are sensitive to XY sex reversal, at least in part, because they carry Wt1(B6) and/or Sf1(B6) alleles that compromise testis differentiation and a Wnt4(B6) allele that promotes ovary differentiation and thereby antagonizes testis differentiation. Addition of a "weak" Sry allele, such as the one on the Y(POS) chromosome, to the sensitized B6 background results in inappropriate development of ovarian tissue. We conclude that Wt1, Sf1, and Wnt4 are dosage-sensitive in mice, this dosage-sensitivity is genetic background-dependant, and the mouse strains described here are good models for the investigation of human dosage-sensitive XY sex reversal. © 2012 Correa et al.
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Stephanie M Correa
Full Text Available Sex reversal can occur in XY humans with only a single functional WT1 or SF1 allele or a duplication of the chromosome region containing WNT4. In contrast, XY mice with only a single functional Wt1, Sf1, or Wnt4 allele, or mice that over-express Wnt4 from a transgene, reportedly are not sex-reversed. Because genetic background plays a critical role in testis differentiation, particularly in C57BL/6J (B6 mice, we tested the hypothesis that Wt1, Sf1, and Wnt4 are dosage sensitive in B6 XY mice. We found that reduced Wt1 or Sf1 dosage in B6 XY(B6 mice impaired testis differentiation, but no ovarian tissue developed. If, however, a Y(AKR chromosome replaced the Y(B6 chromosome, these otherwise genetically identical B6 XY mice developed ovarian tissue. In contrast, reduced Wnt4 dosage increased the amount of testicular tissue present in Sf1+/- B6 XY(AKR, Wt1+/- B6 XY(AKR, B6 XY(POS, and B6 XY(AKR fetuses. We propose that Wt1(B6 and Sf1(B6 are hypomorphic alleles of testis-determining pathway genes and that Wnt4(B6 is a hypermorphic allele of an ovary-determining pathway gene. The latter hypothesis is supported by the finding that expression of Wnt4 and four other genes in the ovary-determining pathway are elevated in normal B6 XX E12.5 ovaries. We propose that B6 mice are sensitive to XY sex reversal, at least in part, because they carry Wt1(B6 and/or Sf1(B6 alleles that compromise testis differentiation and a Wnt4(B6 allele that promotes ovary differentiation and thereby antagonizes testis differentiation. Addition of a "weak" Sry allele, such as the one on the Y(POS chromosome, to the sensitized B6 background results in inappropriate development of ovarian tissue. We conclude that Wt1, Sf1, and Wnt4 are dosage-sensitive in mice, this dosage-sensitivity is genetic background-dependant, and the mouse strains described here are good models for the investigation of human dosage-sensitive XY sex reversal.
Xu, Baozeng; Noohi, Saeid; Shin, Jonghyun S; Tan, Seang Lin; Taketo, Teruko
2014-01-15
The oocyte becomes competent for embryonic development by involving mutual communication with cumulus cells (CCs) during folliculogenesis. How this communication takes place under physiological conditions is not fully understood. Current study examined oocyte-CCs communication in the XY sex-revered female mouse. We have previously found that the XY oocyte is defective in its cytoplasm, causing abnormal MII-spindle assembly and a failure in embryonic development. Our present study showed that transcript levels of Pfkp, Pkm2 and Ldh1 involved in glycolysis were lower in the CCs surrounding XY oocytes than in those surrounding XX oocytes. ATP contents in XY oocytes were also lower than those in XX oocytes, suggesting that lower glycolytic gene expression in CCs resulted in lower ATP contents in the enclosed oocyte. Co-culture of oocytectomized CC-oocyte complexes (COCs) with denuded oocytes showed that XY oocytes were less efficient than XX oocytes in promoting glycolytic gene expression in CCs. Furthermore, both glycolytic gene expression levels in CCs and ATP contents in oocytes of XY COCs increased to similar levels to those of XX COCs after culture for 20h in the presence of milrinone (=preincubation), which prevented spontaneous oocyte maturation. By increasing ATP levels in XY oocytes by either COC preincubation or ATP microinjection into oocytes prior to in vitro maturation, an improvement in MII-spindle assembly was observed. We conclude that the XY oocyte produces lesser amounts of paracrine factors that affect its companion CCs, which in turn make the ooplasm deficient in its components, including ATP, essential for MII-spindle assembly. © 2013 Published by Elsevier Inc.
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Servant Nadège
2010-03-01
Full Text Available Abstract Background Primary amenorrhea due to 46,XY disorders of sex differentiation (DSD is a frequent reason for consultation in endocrine and gynecology clinics. Among the genetic causes of low-testosterone primary amenorrhea due to 46,XY DSD, SRY gene is reported to be frequently involved, but other genes, such as SF1 and WT1, have never been studied for their prevalence. Methods We directly sequenced SRY, SF1 and WT1 genes in 15 adolescent girls with primary amenorrhea, low testosterone concentration, and XY karyotype, to determine the prevalence of mutations. We also analyzed the LH receptor gene in patients with high LH and normal FSH concentrations. Results Among the 15 adolescents with primary amenorrhea and low testosterone concentration, we identified two new SRY mutations, five new SF1 mutations and one new LH receptor gene mutation. Our study confirms the 10-15% prevalence of SRY mutations and shows the high prevalence (33% of SF1 abnormalities in primary amenorrhea due to 46,XY DSD with low plasma testosterone concentration. Conclusions The genetic analysis of low-testosterone primary amenorrhea is complex as several factors may be involved. This work underlines the need to systematically analyze the SF1 sequence in girls with primary amenorrhea due to 46,XY DSD and low testosterone, as well as in newborns with 46,XY DSD.
Wide spectrum of NR5A1‐related phenotypes in 46,XY and 46,XX individuals
Domenice, Sorahia; Machado, Aline Zamboni; Ferreira, Frederico Moraes; Ferraz‐de‐Souza, Bruno; Lerario, Antonio Marcondes; Lin, Lin; Nishi, Mirian Yumie; Gomes, Nathalia Lisboa; da Silva, Thatiana Evelin; Silva, Rosana Barbosa; Correa, Rafaela Vieira; Montenegro, Luciana Ribeiro; Narciso, Amanda; Costa, Elaine Maria Frade; Achermann, John C
2016-01-01
Steroidogenic factor 1 (NR5A1, SF‐1, Ad4BP) is a transcriptional regulator of genes involved in adrenal and gonadal development and function. Mutations in NR5A1 have been among the most frequently identified genetic causes of gonadal development disorders and are associated with a wide phenotypic spectrum. In 46,XY individuals, NR5A1‐related phenotypes may range from disorders of sex development (DSD) to oligo/azoospermia, and in 46,XX individuals, from 46,XX ovotesticular and testicular DSD to primary ovarian insufficiency (POI). The most common 46,XY phenotype is atypical or female external genitalia with clitoromegaly, palpable gonads, and absence of Müllerian derivatives. Notably, an undervirilized external genitalia is frequently seen at birth, while spontaneous virilization may occur later, at puberty. In 46,XX individuals, NR5A1 mutations are a rare genetic cause of POI, manifesting as primary or secondary amenorrhea, infertility, hypoestrogenism, and elevated gonadotropin levels. Mothers and sisters of 46,XY DSD patients carrying heterozygous NR5A1 mutations may develop POI, and therefore require appropriate counseling. Moreover, the recurrent heterozygous p.Arg92Trp NR5A1 mutation is associated with variable degrees of testis development in 46,XX patients. A clear genotype‐phenotype correlation is not seen in patients bearing NR5A1 mutations, suggesting that genetic modifiers, such as pathogenic variants in other testis/ovarian‐determining genes, may contribute to the phenotypic expression. Here, we review the published literature on NR5A1‐related disease, and discuss our findings at a single tertiary center in Brazil, including ten novel NR5A1 mutations identified in 46,XY DSD patients. The ever‐expanding phenotypic range associated with NR5A1 variants in XY and XX individuals confirms its pivotal role in reproductive biology, and should alert clinicians to the possibility of NR5A1 defects in a variety of phenotypes presenting with gonadal
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Nicolescu, Basarab [LPNHE, Unite de Recherche des Universites Paris 6 et Paris 7, associee au CNRS, Theory Group, Universite Pierre et Marie Curie, 4 Place Jussieu, 75252 Paris Cedex 05 (France)
2004-07-01
We consider several classes of analytic parametrizations of hadronic scattering amplitudes (the COMPETE analysis), and compare their predictions to all available forward data (pp, {pi}p, Kp, {gamma}p, {gamma}{gamma}, {sigma}p). Although these parametrizations are very close for {radical}s {>=} 9 GeV, it turns out that they differ markedly at low energy, where a universal Pomeron term {approx} ln{sup 2} s enables one to extend the fit down to {radical}s = 4 GeV. We present predictions on the total cross sections and on the ratio of the real part to the imaginary part of the elastic amplitude ({rho} parameter) for present and future pp colliders, and on total cross sections for {gamma}p {yields} hadrons at cosmic-ray energies and for it{gamma}{gamma} {yields} hadrons up to {radical}s = 1 TeV. The ln{sup 2} s behaviour of total cross sections, first obtained by Heisenberg 50 years ago, receives now increased interest both on phenomenological and theoretical levels. We present a modification of the Heisenberg's model in connection with the presence of glueballs and we show that it leads to a realistic description of all existing hadron total cross-sections data, in agreement with the COMPETE analysis.
Disorders of sex development 45,X/46,XY: clinical and laboratory characteristics of patients
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Oleg Yu. Latyshev
2017-01-01
Full Text Available Aim. To study the clinical and laboratory characteristics of patients with disorders of sex development (DSD 45,Х/46,ХY.Materials and methods. The study included 248 patients with genital malformations from early neonatal period to 18 years. The group of patients with DSD 45,Х/46,ХY was formed according to the results of cytogenetic and molecular cytogenetic examination. Anthropometric data, external and internal genitalia, hormonal parameters in mini-pubertal, neutral and pubertal periods were assessed; histological examination of the gonads and screening of development malformations were performed.Results. DSD of 46,ХY karyotype was revealed in 48% (120/248 cases, 46,ХХ DSD – 38% (93/248, DSD with sex chromosome pathology – 14% (35/248 patients. Chromosome DSD was represented by Klinefelter syndrome, Shereshevsky – Ulrich – Turner syndrome, chimeric DSD, and ovotesticular DSD, but the majority of patients had mosaicism 45,Х/46,ХY (65%. In the group of patients with NFP 45,X/46,XY, the median degree of masculinization of the external genitalia by the scale of the external masculinization score (EMS was 3 [1; 5,5]. Among the defects of external genitalia in most cases (82%, 18/22 there was a combination of cryptorchidism with hypospadias. Derivatives of the Mueller ducts were detected in 91% (20/22 of patients. Most patients (77% adapt the male passport field. There were no statistically significant differences in the structure of the external and internal genitalia between the groups of patients adapted in the male and female passport fields.The analysis of hormonal indexes revealed a positive correlation between the content of basal testosteron in the mini-pubertal period and the index of masculinization of the external genitalia by the EMS scale (p = 0,002; r = 0,9. In the period of mini-puberty an increase in the level of gonadotropic hormones was detected in 89% (8/9 of children, a combined increase of luteinizing and
Agnathia-holoprosencephaly associated with a 46,XY,-21,+t(21q;21q) karyotype
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Niedermeyer, K.K.; McCorquodale, M.M.; Burton, B.K. [Univ. of Illinois, Chicago, IL (United States)
1994-09-01
We report an unusual case of agnathia-holoprosencephaly associated with Down syndrome due to a 21/21 translocation. The patient presented prenatally at 21 wks gestation. A fetal ultrasound revealed multiple CNS anomalies including hydrocephalus, compressed cerebellum, absent septum pellucidum and possible cranial meningocele or encephalocele. High resolution ultrasound & fetal karyotype were recommended. The patient refused & elected to have a pregnancy termination. Chromosomal analysis performed on products of conception revealed a 46,XY,-21,+t(21q;21q) karyotype. Fluorescence in situ hybridization was performed and confirmed the 21/21 translocation chromosome. An autopsy revealed agnathia and multiple CNS anomalies including absence of the septum pellucidum, absence of the corpus callosum, arhinencephaly, an occiptal meningoencephalocele, dilation of the lateral ventricles, and extensive dysgenesis & heterotopias of the central cerebrum & mid-brain. Additional abnormalities included a persistent left superior vena cava, atrial & ventricular septal defects, irregular length of the fingers with absence of the middle phalanges of the right 2nd and 5th & left 5th digits and bilateral simian creases. Agnathia can be an isolated abnormality but often is associated with holoprosencephaly and/or situs inversus. The majority of familial case of agnathis-holoprosencephaly was caused by an inherited unbalanced translocation resulting in duplication of 6p and monosomy of 18p. Our patient had a translocation form of trisomy 21 but did not have a phenotype consistent with Down syndrome. Trisomy 21 has not been previously reported in other cases of agnathia-holoprosencephaly. Whether the chromosomal abnormality caused the phenotypic abnormalities or if it is a coincidental finding cannot be determined.
A Novel Mouse Fgfr2 Mutant, Hobbyhorse (hob), Exhibits Complete XY Gonadal Sex Reversal
Siggers, Pam; Carré, Gwenn-Aël; Bogani, Debora; Warr, Nick; Wells, Sara; Hilton, Helen; Esapa, Chris; Hajihosseini, Mohammad K.; Greenfield, Andy
2014-01-01
The secreted molecule fibroblast growth factor 9 (FGF9) plays a critical role in testis determination in the mouse. In embryonic gonadal somatic cells it is required for maintenance of SOX9 expression, a key determinant of Sertoli cell fate. Conditional gene targeting studies have identified FGFR2 as the main gonadal receptor for FGF9 during sex determination. However, such studies can be complicated by inefficient and variable deletion of floxed alleles, depending on the choice of Cre deleter strain. Here, we report a novel, constitutive allele of Fgfr2, hobbyhorse (hob), which was identified in an ENU-based forward genetic screen for novel testis-determining loci. Fgr2hob is caused by a C to T mutation in the invariant exon 7, resulting in a polypeptide with a mis-sense mutation at position 263 (Pro263Ser) in the third extracellular immunoglobulin-like domain of FGFR2. Mutant homozygous embryos show severe limb and lung defects and, when on the sensitised C57BL/6J (B6) genetic background, undergo complete XY gonadal sex reversal associated with failure to maintain expression of Sox9. Genetic crosses employing a null mutant of Fgfr2 suggest that Fgr2hob is a hypomorphic allele, affecting both the FGFR2b and FGFR2c splice isoforms of the receptor. We exploited the consistent phenotype of this constitutive mutant by analysing MAPK signalling at the sex-determining stage of gonad development, but no significant abnormalities in mutant embryos were detected. PMID:24956260
Vernet, Nadège; Szot, Maria; Mahadevaiah, Shantha K; Ellis, Peter J I; Decarpentrie, Fanny; Ojarikre, Obah A; Rattigan, Áine; Taketo, Teruko; Burgoyne, Paul S
2014-02-01
Outbred XY(Sry-) female mice that lack Sry due to the 11 kb deletion Sry(dl1Rlb) have very limited fertility. However, five lines of outbred XY(d) females with Y chromosome deletions Y(Del(Y)1Ct)-Y(Del(Y)5Ct) that deplete the Rbmy gene cluster and repress Sry transcription were found to be of good fertility. Here we tested our expectation that the difference in fertility between XO, XY(d-1) and XY(Sry-) females would be reflected in different degrees of oocyte depletion, but this was not the case. Transgenic addition of Yp genes to XO females implicated Zfy2 as being responsible for the deleterious Y chromosomal effect on fertility. Zfy2 transcript levels were reduced in ovaries of XY(d-1) compared with XY(Sry-) females in keeping with their differing fertility. In seeking the biological basis of the impaired fertility we found that XY(Sry-), XY(d-1) and XO,Zfy2 females produce equivalent numbers of 2-cell embryos. However, in XY(Sry-) and XO,Zfy2 females the majority of embryos arrested with 2-4 cells and almost no blastocysts were produced; by contrast, XY(d-1) females produced substantially more blastocysts but fewer than XO controls. As previously documented for C57BL/6 inbred XY females, outbred XY(Sry-) and XO,Zfy2 females showed frequent failure of the second meiotic division, although this did not prevent the first cleavage. Oocyte transcriptome analysis revealed major transcriptional changes resulting from the Zfy2 transgene addition. We conclude that Zfy2-induced transcriptional changes in oocytes are sufficient to explain the more severe fertility impairment of XY as compared with XO females.
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Barmettler, Peter; Gritsev, Vladimir [Department of Physics, University of Fribourg, CH-1700 Fribourg (Switzerland); Punk, Matthias [CPHT, Ecole Polytechnique, 91128 Palaiseau (France); Demler, Eugene [Department of Physics, Harvard University, Cambridge, MA 02138 (United States); Altman, Ehud, E-mail: peter.barmettler@cpht.polytechnique.f [Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100 (Israel)
2010-05-15
Recent experimental achievements in controlling ultracold gases in optical lattices open a new perspective on quantum many-body physics. In these experimental setups, it is possible to study coherent time evolution of isolated quantum systems. These dynamics reveal new physics beyond the low-energy properties that are usually relevant in solid-state many-body systems. In this paper, we study the time evolution of antiferromagnetic order in the Heisenberg chain after a sudden change of the anisotropy parameter, using various numerical and analytical methods. As a generic result, we find that the order parameter, which can show oscillatory or non-oscillatory dynamics, decays exponentially except for the effectively non-interacting case of the XX limit. For weakly ordered initial states, we also find evidence for an algebraic correction to the exponential law. The study is based on numerical simulations using a numerical matrix product method for infinite system sizes (iMPS), for which we provide a detailed description and an error analysis. Additionally, we investigate in detail the exactly solvable XX limit. These results are compared to approximative analytical approaches including an effective description by the XZ model as well as by mean-field, Luttinger-liquid and sine-Gordon theories. The comparison reveals which aspects of non-equilibrium dynamics can, as in equilibrium, be described by low-energy theories and which are the novel phenomena specific to quantum quench dynamics. The relevance of the energetically high part of the spectrum is illustrated by means of a full numerical diagonalization of the Hamiltonian.
DEFF Research Database (Denmark)
Enderle, M.; Kiefer, K.; Klopperpieper, A.
2000-01-01
Uniform S = 1 and 1/2 Heisenberg antiferromagnetic chains have a quantum singlet ground state which is an eigenstate of the total spin with S(tot) = 0. However, the 'internal' order of these ground states is quite different, and is reflected in gapless excitations in the S = 1/2 state, while the ...
Strečka, Jozef; Alécio, Raphael Cavalcante; Lyra, Marcelo L.; Rojas, Onofre
2016-07-01
The spin-1/2 Ising-Heisenberg three-leg tube composed of the Heisenberg spin triangles mutually coupled through the Ising inter-triangle interaction is exactly solved in a zero magnetic field. By making use of the local conservation for the total spin on each Heisenberg spin triangle the model can be rigorously mapped onto a classical composite spin-chain model, which is subsequently exactly treated through the transfer-matrix method. The ground-state phase diagram, correlation functions, concurrence, Bell function, entropy and specific heat are examined in detail. It is shown that the spin frustration represents an indispensable ground for a thermal entanglement, which is quantified by the quantum concurrence. The specific heat displays diverse temperature dependences, which may include a sharp low-temperature peak mimicking a temperature-driven first-order phase transition. It is convincingly evidenced that this anomalous peak originates from massive thermal excitations from the doubly degenerate ground state towards an excited state with a high macroscopic degeneracy due to chiral degrees of freedom of the Heisenberg spin triangles.
DEFF Research Database (Denmark)
Clarke, S.J.; Harrison, A.; Mason, T.E.
1999-01-01
Copper(II) formate tetrahydrate (CFTH) is a model square S = 1/2 Heisenberg antiferromagnet with T-N = 16.54 +/- 0.05 K. The dispersion of spin-waves in the magnetic layers of a fully deuterated sample of this material has been mapped at 4.3 K by inelastic neutron scattering from the zone centre ...
Kocmarek, Andrea L; Ferguson, Moira M; Danzmann, Roy G
2015-04-01
All-female lines of fish are created by crossing sex reversed (XX genotype) males with normal females. All-female lines avoid the deleterious phenotypic effects that are typical of precocious maturation in males. To determine whether all-female and mixed sex populations of rainbow trout (Oncorhynchus mykiss) differ in performance, we compared the growth and gene expression profiles in progeny groups produced by crossing a XX male and a XY male to the same five females. Body weight and length were measured in the resulting all-female (XX) and mixed sex (XX/XY) offspring groups. Microarray experiments with liver and white muscle were used to determine if the gene expression profiles of large and small XX offspring differ from those in large and small XX/XY offspring. We detected no significant differences in body length and weight between offspring groups but XX offspring were significantly less variable in the value of these traits. A large number of upregulated genes were shared between the large XX and large XX/XY offspring; the small XX and small XX/XY offspring also shared similar expression profiles. No GO category differences were seen in the liver or between the large XX and large XX/XY offspring in the muscle. The greatest differences between the small XX and small XX/XY offspring were in the genes assigned to the "small molecule metabolic process" and "cellular metabolic process" GO level 3 categories. Similarly, genes within these categories as well as the category "macromolecule metabolic process" were more highly expressed in small compared to large XX fish.
Werner, Ralf; Merz, Hartmut; Birnbaum, Wiebke; Marshall, Louise; Schröder, Tatjana; Reiz, Benedikt; Kavran, Jennifer M; Bäumer, Tobias; Capetian, Philipp; Hiort, Olaf
2015-07-01
46,XY disorders of sex development (DSD) comprise a heterogeneous group of congenital conditions. Mutations in a variety of genes can affect gonadal development or androgen biosynthesis/action and thereby influence the development of the internal and external genital organs. The objective of the study was to identify the genetic cause in two 46,XY sisters of a consanguineous family with DSD and gonadal tumor formation. We used a next-generation sequencing approach by exome sequencing. Electrophysiological and high-resolution ultrasound examination of peripheral nerves as well as histopathological examination of the gonads were performed. We identified a novel homozygous R124Q mutation in the desert hedgehog gene (DHH), which alters a conserved residue among the three mammalian Hedgehog ligands sonic hedgehog, Indian hedgehog, and desert hedgehog. No other relevant mutations in DSD-related genes were encountered. The gonads of one patient showed partial gonadal dysgenesis with loss of Leydig cells in tubular areas with seminoma in situ and a hyperplasia of Leydig cell-like cells expressing CYP17A1 in more dysgenetic parts of the gonad. In addition, both patients suffer from a polyneuropathy. High-resolution ultrasound revealed a structural change of peripheral nerve structure that fits well to a minifascicle formation of peripheral nerves. Mutations in DHH play a role in 46,XY gonadal dysgenesis and are associated with seminoma formation and a neuropathy with minifascicle formation. Gonadal dysgenesis in these cases may be due to impairment of Sertoli cell-Leydig cell interaction during gonadal development.
Critical behavior of the Higgs- and Goldstone-mass gaps for the two-dimensional S=1 XY model
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Yoshihiro Nishiyama
2015-08-01
Full Text Available Spectral properties for the two-dimensional quantum S=1 XY model were investigated with the exact diagonalization method. In the symmetry-broken phase, there appear the massive Higgs and massless Goldstone excitations, which correspond to the longitudinal and transverse modes of the spontaneous magnetic moment, respectively. The former excitation branch is embedded in the continuum of the latter, and little attention has been paid to the details, particularly, in proximity to the critical point. The finite-size-scaling behavior is improved by extending the interaction parameters. An analysis of the critical amplitude ratio for these mass gaps is made.
Kevin L. Sager
2015-01-01
Este estudio analizó el grado en el que puede predecirse por parte de los superiores la comunicación descendente de mantenimiento a partir de los supuestos de la teoría X/Y. En la primera fase del estudio se desarrollo una medida de autoinforme de la comunicación descendente de mantenimiento. El análisis de componentes principales dio como resultado tres categorías de comunicación de mantenimiento: confirmación descendente, evitación del conflicto descendente y urbanidad descendente. En una s...
A 45,X/46,XY Male with Orchidopexy Diagnosed with Mixed Germ Cell Tumor After 21-year Follow-up
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Masashi Kubota
2017-07-01
Full Text Available A case of a 45,X/46,XY boy with gonadal dysgenesis is presented. The patient showed hypospadias and right undescended testis. He underwent underwent repair surgery for hypospadias, right orchidopexy, and bilateral testicular biopsy. Testicular biopsy revealed no malignant finding. He was followed-up annually by scrotum palpation. When the patient grew up to 24 years old, he was diagnosed to have right testicular tumor. High orchiectomy revealed pT1 seminoma. The management of undescended testis in men with gonadal dysgenesis and disordered sexual development is discussed.
Liu, X M; Cheng, W W; Liu, J-M
2016-01-19
We investigate the quantum Fisher information and quantum phase transitions of an XY spin chain with staggered Dzyaloshinskii-Moriya interaction using the quantum renormalization-group method. The quantum Fisher information, its first-derivatives, and the finite-size scaling behaviors are rigorously calculated respectively. The singularity of the derivatives at the phase transition point as a function of lattice size is carefully discussed and it is revealed that the scaling exponent for quantum Fisher information at the critical point can be used to describe the correlation length of this model, addressing the substantial role of staggered Dzyaloshinskii-Moriya interaction in modulating quantum phase transitions.