6,780 research outputs found
Quantum control of a spin qubit coupled to a photonic crystal cavity
A key ingredient for a quantum network is an interface between stationary
quantum bits and photons, which act as flying qubits for interactions and
communication. Photonic crystal architectures are promising platforms for
enhancing the coupling of light to solid state qubits. Quantum dots can be
integrated into a photonic crystal, with optical transitions coupling to
photons and spin states forming a long-lived quantum memory. Many researchers
have now succeeded in coupling these emitters to photonic crystal cavities, but
there have been no demonstrations of a functional spin qubit and quantum gates
in this environment. Here we have developed a coupled cavity-quantum dot system
in which the dot is controllably charged with a single electron. We perform the
initialization, rotation and measurement of a single electron spin qubit using
laser pulses and find that the cavity can significantly improve these
processes
Color Capable Sub-Pixel Resolving Optofluidic Microscope and Its Application to Blood Cell Imaging for Malaria Diagnosis
Miniaturization of imaging systems can significantly benefit clinical diagnosis in challenging environments, where access to physicians and good equipment can be limited. Sub-pixel resolving optofluidic microscope (SROFM) offers high-resolution imaging in the form of an on-chip device, with the combination of microfluidics and inexpensive CMOS image sensors. In this work, we report on the implementation of color SROFM prototypes with a demonstrated optical resolution of 0.66 µm at their highest acuity. We applied the prototypes to perform color imaging of red blood cells (RBCs) infected with Plasmodium falciparum, a particularly harmful type of malaria parasites and one of the major causes of death in the developing world
Universal finite size corrections and the central charge in non solvable Ising models
We investigate a non solvable two-dimensional ferromagnetic Ising model with
nearest neighbor plus weak finite range interactions of strength \lambda. We
rigorously establish one of the predictions of Conformal Field Theory (CFT),
namely the fact that at the critical temperature the finite size corrections to
the free energy are universal, in the sense that they are exactly independent
of the interaction. The corresponding central charge, defined in terms of the
coefficient of the first subleading term to the free energy, as proposed by
Affleck and Blote-Cardy-Nightingale, is constant and equal to 1/2 for all
0<\lambda<\lambda_0 and \lambda_0 a small but finite convergence radius. This
is one of the very few cases where the predictions of CFT can be rigorously
verified starting from a microscopic non solvable statistical model. The proof
uses a combination of rigorous renormalization group methods with a novel
partition function inequality, valid for ferromagnetic interactions.Comment: 43 pages, 1 figur
Draft genomes of two Artocarpus plants, jackfruit (A. heterophyllus) and breadfruit (A. altilis)
Two of the most economically important plants in the Artocarpus genus are jackfruit (A. heterophyllus Lam.) and breadfruit (A. altilis (Parkinson) Fosberg). Both species are long-lived trees that have been cultivated for thousands of years in their native regions. Today they are grown throughout tropical to subtropical areas as an important source of starch and other valuable nutrients. There are hundreds of breadfruit varieties that are native to Oceania, of which the most commonly distributed types are seedless triploids. Jackfruit is likely native to the Western Ghats of India and produces one of the largest tree-borne fruit structures (reaching up to 45 kg). To-date, there is limited genomic information for these two economically important species. Here, we generated 273 Gb and 227 Gb of raw data from jackfruit and breadfruit, respectively. The high-quality reads from jackfruit were assembled into 162,440 scaffolds totaling 982 Mb with 35,858 genes. Similarly, the breadfruit reads were assembled into 180,971 scaffolds totaling 833 Mb with 34,010 genes. A total of 2822 and 2034 expanded gene families were found in jackfruit and breadfruit, respectively, enriched in pathways including starch and sucrose metabolism, photosynthesis, and others. The copy number of several starch synthesis-related genes were found to be increased in jackfruit and breadfruit compared to closely-related species, and the tissue-specific expression might imply their sugar-rich and starch-rich characteristics. Overall, the publication of high-quality genomes for jackfruit and breadfruit provides information about their specific composition and the underlying genes involved in sugar and starch metabolism
ZNF750 is a lineage-specific tumour suppressor in squamous cell carcinoma.
ZNF750 controls epithelial homeostasis by regulating epidermal-differentiation genes, a role underscored by its pathogenic mutations in esophageal squamous cell cancers (SCCs). However, the precise role of ZNF750 in SCC cell biology remains unclear. In this study, we report that ZNF750 is exclusively deleted, mutated and underexpressed in human SCCs, and low ZNF750 expression is associated with poor survival. Restoration of wildtype, but not mutant ZNF750 protein uniquely inhibited the malignant phenotypes of SCC cells both in vitro and in vivo. Notably, ZNF750 promoted the expression of a long non-coding RNA (TINCR), which mediated both cancer-inhibition and differentiation-induction effects of ZNF750. In addition, ZNF750 potently suppressed cell migration by directly inhibiting the transactivation of LAMC2. Together, our findings characterize ZNF750 as a crucial SCC-specific suppressor and uncover its novel anticancer-associated functions
An efficient basis set representation for calculating electrons in molecules
The method of McCurdy, Baertschy, and Rescigno, J. Phys. B, 37, R137 (2004)
is generalized to obtain a straightforward, surprisingly accurate, and scalable
numerical representation for calculating the electronic wave functions of
molecules. It uses a basis set of product sinc functions arrayed on a Cartesian
grid, and yields 1 kcal/mol precision for valence transition energies with a
grid resolution of approximately 0.1 bohr. The Coulomb matrix elements are
replaced with matrix elements obtained from the kinetic energy operator. A
resolution-of-the-identity approximation renders the primitive one- and
two-electron matrix elements diagonal; in other words, the Coulomb operator is
local with respect to the grid indices. The calculation of contracted
two-electron matrix elements among orbitals requires only O(N log(N))
multiplication operations, not O(N^4), where N is the number of basis
functions; N = n^3 on cubic grids. The representation not only is numerically
expedient, but also produces energies and properties superior to those
calculated variationally. Absolute energies, absorption cross sections,
transition energies, and ionization potentials are reported for one- (He^+,
H_2^+ ), two- (H_2, He), ten- (CH_4) and 56-electron (C_8H_8) systems.Comment: Submitted to JC
Classical dimers on the triangular lattice
We study the classical hard-core dimer model on the triangular lattice.
Following Kasteleyn's fundamental theorem on planar graphs, this problem is
soluble by Pfaffians. This model is particularly interesting for, unlike the
dimer problems on the bipartite square and hexagonal lattices, its correlations
are short ranged with a correlation length of less than one lattice constant.
We compute the dimer-dimer and monomer-monomer correlators, and find that the
model is deconfining: the monomer-monomer correlator falls off exponentially to
a constant value sin(pi/12)/sqrt(3) = .1494..., only slightly below the
nearest-neighbor value of 1/6. We also consider the anisotropic triangular
lattice model in which the square lattice is perturbed by diagonal bonds of one
orientation and small fugacity. We show that the model becomes non-critical
immediately and that this perturbation is equivalent to adding a mass term to
each of two Majorana fermions that are present in the long wavelength limit of
the square-lattice problem.Comment: 15 pages, 5 figures. v2: includes analytic value of monomer-monomer
correlator, changes titl
- …
