Loss of Exchange Symmetry in Multiqubit States under Ising Chain Evolution

Keeping in view of importance of exchange symmetry aspects in studies on spin squeezing of multiqubit states, we show that the one-dimensional Ising Hamiltonian with nearest neighbor interactions does not retain the exchange symmetry of initially symmetric multiqubit states. Specifically we show that among 4-qubit states obeying exchange symmetry, all states except W class (and their linear combination) lose their symmetry under time evolution with Ising Hamiltonian. Attributing the loss of symmetry of the initially symmetric states to rotational asymmetry of the one-dimensional Ising Hamiltonian with more than 3 qubits, we indicate that all N-qubit states (N >= 5) obeying permutation symmetry lose their symmetry after time evolution with Ising Hamiltonian

Novel conopeptides of largely unexplored Indo Pacific <i>Conus</i> sp.

Cone snails are predatory creatures using venom as a weapon for prey capture and defense. Since this venom is neurotoxic, the venom gland is considered as an enormous collection of pharmacologically interesting compounds having a broad spectrum of targets. As such, cone snail peptides represent an interesting treasure for drug development. Here, we report five novel peptides isolated from the venom of Conus longurionis, Conus asiaticus and Conus australis. Lo6/7a and Lo6/7b were retrieved from C. longurionis and have a cysteine framework VI/VII. Lo6/7b has an exceptional amino acid sequence because no similar conopeptide has been described to date (similarity percentage C. asiaticus, has a typical framework III Cys arrangement, classifying the peptide in the M-superfamily. Asi14a, another peptide of C. asiaticus, belongs to framework XIV peptides and has a unique amino acid sequence. Finally, AusB is a novel conopeptide from C. australis. The peptide has only one disulfide bond, but is structurally very different as compared to other disulfide-poor peptides. The peptides were screened on nAChRs, NaV and KV channels depending on their cysteine framework and proposed classification. No targets could be attributed to the peptides, pointing to novel functionalities. Moreover, in the quest of identifying novel pharmacological targets, the peptides were tested for antagonistic activity against a broad panel of Gram-negative and Gram-positive bacteria, as well as two yeast strains

Local Unitary Invariant Spin-Squeezing in Multiqubit States

We investiage Local Unitary Invariant Spin Squeezing (LUISS) in symmetric and non-symmetric multiqubit states. On developing an operational procedure to evaluate Local Unitary Invariant Spin Squeezing parameters, we explicitly evaluate these parameters for pure as well as mixed non-symmetric multiqubit states. We show that the existence of local unitary invariant version of Kitegawa-Ueda spin squeezing may not witness pairwise entanglement whereas the local unitary invariant analogue of Wineland spin squeezing necessarily implies pairwise entanglement. © 2015 Springer Science+Business Media New Yor

The comparative role of key environmental factors in determining savanna productivity and carbon fluxes: a review, with special reference to northern Australia

Terrestrial ecosystems are highly responsive to their local environments and, as such, the rate of carbon uptake both in shorter and longer timescales and different spatial scales depends on local environmental drivers. For savannas, the key environmental drivers controlling vegetation productivity are water and nutrient availability, vapour pressure deficit (VPD), solar radiation and fire. Changes in these environmental factors can modify the carbon balance of these ecosystems. Therefore, understanding the environmental drivers responsible for the patterns (temporal and spatial) and processes (photosynthesis and respiration) has become a central goal in terrestrial carbon cycle studies. Here we have reviewed the various environmental controls on the spatial and temporal patterns on savanna carbon fluxes in northern Australia. Such studies are critical in predicting the impacts of future climate change on savanna productivity and carbon storage