Equivalence of Tripartite Quantum States under Local Unitary Transformations

The equivalence of tripartite pure states under local unitary transformations is investigated. The nonlocal properties for a class of tripartite quantum states in \Cb^K \otimes \Cb^M \otimes \Cb^N composite systems are investigated and a complete set of invariants under local unitary transformations for these states is presented. It is shown that two of these states are locally equivalent if and only if all these invariants have the same values.Comment: 7 page

Multipartite states under local unitary transformations

The equivalence problem under local unitary transformation for $n$--partite pure states is reduced to the one for $(n-1)$--partite mixed states. In particular, a tripartite system $\mathcal{H}_A\otimes\mathcal{H}_B\otimes\mathcal{H}_C$, where $\mathcal{H}_j$ is a finite dimensional complex Hilbert space for $j=A,B,C$, is considered and a set of invariants under local transformations is introduced, which is complete for the set of states whose partial trace with respect to $\mathcal{H}_A$ belongs to the class of generic mixed states.Comment: Latex, 10 page

Mukhanov-Sasaki equation in manifestly gauge-invariant linearized cosmological perturbation theory with dust reference fields

The aim of this article is to understand the role of dust reference fields, often also called clocks, on cosmological perturbations around a flat FLRW universe. We derive the Mukhanov-Sasaki (MS) equation for the Brown-Kuchar (BK) and Gaussian dust models, which both consider four dust fields as reference fields. The reduced phase space of Dirac observables, that is the gauge-invariant part of the theory, is constructed by means of an observable map applied to all elementary phase space variables of the coupled system, consisting of gravity, a massive scalar field and the dust degrees of freedom. The evolution of these observables is governed by a so called physical Hamiltonian which can be derived once the set of reference fields are chosen and differs for each model. First, the reduced phase space as well as the corresponding equations of motion are derived for full general relativity. Then from this, the gauge-invariant version of the equations of motion for the background are derived which contain a fingerprint of the dust reference fields. Afterwards we study linear cosmological perturbations around a FLRW metric using the scalar-vector-tensor decomposition and derive the equation of motion for the MS variable in this formalism for a chosen set of variables on the reduced phase space and expressed in terms of Dirac observables. The MS equation involves additional contributions that can be understood as back reactions from the dust reference fields. These additional dust contributions to the MS equation were absent if the dust energy and momentum density as well as their perturbations are vanishing. The nature of the correction terms suggest that BK and Gaussian dust reference fields contribute differently. Using numerical simulations we study the behavior of the dust contributions to the MS equation during inflation.Comment: Revised version. Analysis and comparison of two dust models extended to investigate Mukhanov-Sasaki variable with now corrected contribution for Brown-Kuchar model. Figures added and updated. To appear in Phys. Rev.

How relevant are Hofstede’s dimensions for inter-cultural studies? A replication of Hofstede’s research among current international business students

In the present study the cultural dimensions of the well known Dutch researcher Geert Hofstede were tested on a sample of international business students. The sample consisted of 1 033 students from the Netherlands, Germany, China, South Africa and Qatar. The findings of the present research contest many of Hofstede’s original findings. The dimensions power distance and long-term orientation show significant differences with Hofstede’s original country values. The dimensions individualism, masculinity and uncertainty avoidance show significant differences for half of the countries. No significant differences were found between male and female students. The results show– if anything – that Hofstede seems to be right with his warning to be careful with relatively small samples. Or, it might be that cultures are less stable after all.Keywords: Hofstede’s cultural dimensions; Dutch, German, Chinese, South African, Qatari business student

Massive thymic deletion results in systemic autoimmunity through elimination of CD4+ CD25+ T regulatory cells

Incomplete deletion of KRN T cells that recognize the ubiquitously expressed self-antigen glucose-6-phosphate-isomerase (GPI) initiates an anti-GPI autoimmune cascade in K/BxN mice resulting in a humorally mediated arthritis. Transgenic (Tg) expression of a KRN T cell receptor (TCR) agonist under the major histocompatibility complex class II promoter resulted in thymic deletion with loss of anti-GPI T and B cell responses and attenuated arthritis course. However, double Tg mice succumbed to systemic autoimmunity with multiorgan inflammation and autoantibody production. Extensive thymic deletion resulted in lymphopenia and elimination of CD4(+) CD25(+) regulatory T cells (Tregs), but spared some CD4(+) T cells expressing endogenous TCR, which oligoclonally expanded in the periphery. Disease was transferred by these T cells and prevented by cotransfer of CD4(+) CD25(+) Tregs. Moreover, we extended our findings to another TCR system (anti–hen egg lysozyme [HEL] TCR/HEL mice) where similarly extensive thymic deletion also resulted in disease. Thus, our studies demonstrated that central tolerance can paradoxically result in systemic autoimmunity through differential susceptibility of Tregs and autoreactive T cells to thymic deletion. Therefore, too little or too much negative selection to a self-antigen can result in systemic autoimmunity and disease

An Extended Plant Circadian Clock Model for Characterising Flowering Time under Different Light Quality Conditions

Speed breeding has recently emerged as an innovative agricultural technology solution to meet the ever-increasing global food demand. In speed breeding, typically various light qualities (e.g., colour, duration, intensity) are modified to manipulate the circadian clock of the plants, which in turn alter the plant growth and enhance the productivity such as by reducing the flowering time. In order to develop a comprehensive framework describing plant growth, a model incorporating the effect of various light qualities on plant growth needs to be established. Recently a mathematical model of the plant circadian clock for Arabidopsis thaliana has been developed to characterise the hypocotyl growth subject to multiple light quality properties. This is a first step towards developing a more comprehensive model that links light quality, plant circadian clock and plant growth. In this work, we extend the model by adding the effect of various light qualities on the flowering time. The proposed model can capture the flowering time behaviours of plant when subject to red, blue, and mixed lights and can be used to guide experiment of light properties manipulation for optimised plant growth via hypocotyl growth and flowering time

One Solution to the Mass Budget Problem for Planet Formation: Optically Thick Disks with Dust Scattering

Atacama Large Millimeter Array (ALMA) surveys have suggested that the dust in Class II disks may not be enough to explain the averaged solid mass in exoplanets, under the assumption that the mm disk continuum emission is optically thin. This optically thin assumption seems to be supported by recent Disk Substructures at High Angular Resolution Project (DSHARP) observations where the measured optical depths are mostly less than one. However, we point out that dust scattering can considerably reduce the emission from an optically thick region. If that scattering is ignored, an optically thick disk with scattering can be misidentified as an optically thin disk. Dust scattering in more inclined disks can reduce the intensity even further, making the disk look even fainter. The measured optical depth of ~0.6 in several DSHARP disks can be naturally explained by optically thick dust with an albedo of ~0.9 at 1.25 mm. Using the DSHARP opacity, this albedo corresponds to a dust population with the maximum grain size (s max) of 0.1–1 mm. For optically thick scattering disks, the measured spectral index α can be either larger or smaller than 2 depending on whether the dust albedo increases or decreases with wavelength. We describe how this optically thick scattering scenario could explain the observed scaling between submm continuum sizes and luminosities, and might help ease the tension between the dust size constraints from polarization and dust continuum measurements. We suggest that a significant amount of disk mass can be hidden from ALMA observations and longer wavelength observations (e.g., Very Large Array or Square Kilometre Array) are desired to probe the dust mass in disks

Restriction landmark genomic scanning (RLGS) spot identification by second generation virtual RLGS in multiple genomes with multiple enzyme combinations.

BackgroundRestriction landmark genomic scanning (RLGS) is one of the most successfully applied methods for the identification of aberrant CpG island hypermethylation in cancer, as well as the identification of tissue specific methylation of CpG islands. However, a limitation to the utility of this method has been the ability to assign specific genomic sequences to RLGS spots, a process commonly referred to as "RLGS spot cloning."ResultsWe report the development of a virtual RLGS method (vRLGS) that allows for RLGS spot identification in any sequenced genome and with any enzyme combination. We report significant improvements in predicting DNA fragment migration patterns by incorporating sequence information into the migration models, and demonstrate a median Euclidian distance between actual and predicted spot migration of 0.18 centimeters for the most complex human RLGS pattern. We report the confirmed identification of 795 human and 530 mouse RLGS spots for the most commonly used enzyme combinations. We also developed a method to filter the virtual spots to reduce the number of extra spots seen on a virtual profile for both the mouse and human genomes. We demonstrate use of this filter to simplify spot cloning and to assist in the identification of spots exhibiting tissue-specific methylation.ConclusionThe new vRLGS system reported here is highly robust for the identification of novel RLGS spots. The migration models developed are not specific to the genome being studied or the enzyme combination being used, making this tool broadly applicable. The identification of hundreds of mouse and human RLGS spot loci confirms the strong bias of RLGS studies to focus on CpG islands and provides a valuable resource to rapidly study their methylation

Scale Up Isolation of Aaptamine for In Vivo Evaluation Indicates Its Neurobiological Activity is Linked to the Delta Opioid Receptor

Opioid receptors belong to the large superfamily of seven transmembrane-spanning (7TM) G protein-coupled receptors (GPCRs). As a class, GPCRs are of fundamental physiological importance mediating the actions of the majority of known neurotransmitters and hormones. The Mu, Delta, and Kappa (MOP, DOP, KOP) opioid receptors are particularly intriguing members of this receptor family as they are the targets involved in many neurobiological diseases such as addiction, pain, stress, anxiety, and depression. Recently we discovered that the aaptamine class of marine sponge derived natural products exhibit selective agonist activity in vitro for the DOP versus MOP receptor. Our findings may explain reports by others that aaptamine demonstrates in vivo anti-depressant effects in mouse models using the Porsolt Forced Swim Test. This project involved the extraction of the sponge Aaptos aaptos (a source of 1), establishing a scale up purification procedure to provide sufficient amounts of 1 (30 mg) for a follow up in vivo evaluation and ultimately confirmation of the structure of 1 using LC-MS and 1H NMR. The results our purification scheme, chemical analysis and in vivo evaluation of 1 using the Marble burying test in rodents are reported here in and suggest that the in vivo anti-depressant effects of 1 are linked directly to its agonist effects on the DOP receptor.https://scholar.dominican.edu/ug-student-posters/1008/thumbnail.jp