Spin Star as Switch for Quantum Networks

Quantum state transfer is an important task in quantum information processing. It is known that one can engineer the couplings of a one-dimensional spin chain to achieve the goal of perfect state transfer. To leverage the value of these spin chains, a spin star is potentially useful for connecting different parts of a quantum network. In this work, we extend the spin-chain engineering problem to the problems with a topology of a star network. We show that a permanently coupled spin star can function as a network switch for transferring quantum states selectively from one node to another by varying the local potentials only. Together with one-dimensional chains, this result allows applications of quantum state transfer be applied to more general quantum networks.Comment: 10 pages, 2 figur

Greenhouse effect due to atmospheric nitrous oxide

The greenhouse effect due to nitrous oxide in the present atmosphere is about 0.8°K. Increase in atmospheric N_2O due to perturbation of the nitrogen cycle by man may lead to an increase in surface temperature as large as 0.5°K by 2025, or 1.0°K by 2100. Other climatic effects of N_2O are briefly discussed

Model documentation, chapter 4

The modeling groups are listed along with a brief description of the respective models

Domain Walls and Flux Tubes in N=2 SQCD: D-Brane Prototypes

This paper could have been entitled "D branes and strings from flesh and blood." We study field theoretic prototypes of D branes/strings. To this end we consider (2+1)-dimensional domain walls in (3+1)-dimensional N=2 SQCD with SU(2) gauge group and two quark flavors in the fundamental representation. This theory is perturbed by a small mass term of the adjoint matter which, in the leading order in the mass parameter, does not break N=2 supersymmetry, and reduces to a (generalized) Fayet-Iliopoulos term in the effective low-energy N=2 SQED. We find 1/2 BPS-saturated domain wall solution interpolating between two quark vacua at weak coupling, and show that this domain wall localizes a U(1) gauge field. To make contact with the brane/string picture we consider the Abrikosov-Nielsen-Olesen magnetic flux tube in one of two quark vacua and demonstrate that it can end on the domain wall. We find an explicit 1/4 BPS-saturated solution for the wall/flux tube junction. We verify that the end point of the flux tube on the wall plays the role of an electric charge in the dual (2+1)-dimensional SQED living on the wall. Flow to N=1 theory is discussed. Our results lead us to a conjecture regarding the notorious "missing wall" in the solution of Kaplunovsky et al.Comment: 41 pages, 5 figures, Sect. 9.3 expanded, typos correcte

Acute Neurological Toxicity (NT) and Long-Term Outcomes in High-grade Glioma RTOG Trials

Background: Treatment of high-grade glioma consists of fractionated radiation therapy (RT) ± chemotherapy. The incidence/significance of neurological toxicity (NT) in this disease is not known. We evaluated the relationship between acute and chronic NT, and ultimate outcome, as well as risk factors for NT from the RTOG database. American Society of Clinical Oncology (ASCO) 46th Annual Meeting June 4-8, Chicago, IL

Bulk Fermi surface and momentum density in heavily doped La2−x_{2-x}Srx_xCuO4_4 using high resolution Compton scattering and positron annihilation spectroscopies

We have observed the bulk Fermi surface (FS) in an overdoped ($x$=0.3) single crystal of La$_{2-x}$Sr$_x$CuO$_4$ by using Compton scattering. A two-dimensional (2D) momentum density reconstruction from measured Compton profiles yields a clear FS signature in the third Brillouin zone along [100]. The quantitative agreement between density functional theory (DFT) calculations and momentum density experiment suggests that Fermi-liquid physics is restored in the overdoped regime. In particular the predicted FS topology is found to be in good accord with the corresponding experimental data. We find similar quantitative agreement between the measured 2D angular correlation of positron annihilation radiation (2D-ACAR) spectra and the DFT based computations. However, 2D-ACAR does not give such a clear signature of the FS in the extended momentum space in either the theory or the experiment.Comment: 9 pages, 8 figure

Generation of atom-light entanglement in an optical cavity for quantum enhanced atom interferometry

We theoretically investigate the generation of atom-light entanglement via Raman superradiance in an optical cavity, and show how this can be used to enhance the sensitivity of atom interferometry. We model a realistic optical cavity, and show that by careful temporal shaping of the optical local oscillator used to measure the light emitted from the cavity, information in the optical mode can be combined with the signal from the atom interferometer to reduce the quantum noise, and thus increase the sensitivity. It was found in Phys. Rev. Lett. 110, 053002 (2013) that an atomic “seed” was required in order to reduce spontaneous emission and allow for single mode behavior of the device. In this paper we find that the optical cavity reduces the need for an atomic seed, which allows for stronger atom-light correlations and a greater level of quantum enhancement

Hamiltonian structures of fermionic two-dimensional Toda lattice hierarchies

By exhibiting the corresponding Lax pair representations we propose a wide class of integrable two-dimensional (2D) fermionic Toda lattice (TL) hierarchies which includes the 2D N=(2|2) and N=(0|2) supersymmetric TL hierarchies as particular cases. We develop the generalized graded R-matrix formalism using the generalized graded bracket on the space of graded operators with involution generalizing the graded commutator in superalgebras, which allows one to describe these hierarchies in the framework of the Hamiltonian formalism and construct their first two Hamiltonian structures. The first Hamiltonian structure is obtained for both bosonic and fermionic Lax operators while the second Hamiltonian structure is established for bosonic Lax operators only.Comment: 12 pages, LaTeX, the talks delivered at the International Workshop on Classical and Quantum Integrable Systems (Dubna, January 24 - 28, 2005) and International Conference on Theoretical Physics (Moscow, April 11 - 16, 2005

Managing organizational DSS development in small manufacturing enterprise

A number of Hong Kong manufacturing companies have moved their production to the People's Republic of China while retaining their supporting functions (such as marketing, distribution, etc.) in Hong Kong. As a consequence, their mode of operation has become more complex and demands better production planning and control (PPC). One solution is to use an information system in which all factory resources are integrated within a single framework for PPC. The main instrument of this strategy is an Organizational DSS (ODSS). This paper presents a case study of development and adoption of an ODSS in a small manufacturing enterprise. Analysis of the findings highlights the cultural as well as organizational underpinnings and the need for effective intervention before and throughout the computerization. The implementation strategies are described, with emphasis on prerequisite infrastructural developments, showing how they provide opportunities and constraints

Ecology of the Missouri River: Missouri River Creel Survey, Bellevue Bridge to Camp Creek, 3 April through 29 May 2004

The Nebraska Game and Parks Commission\u27s strategic plan has stated the following management goal for the Missouri River: Restore, protect, and maintain the diversity of historic Missouri River habitats, resources, and ecosystem functions in order that present and future generations may enjoy consumptive and non-consumptive outdoor recreational opportunities (NGPC 1996). To accomplish this goal the Nebraska Game and Parks Commission identified the following five objectives: • To restore terrestrial and aquatic floodplain habitat types by 2008. This would include old oxbows, chutes, side channels, sand bars, backwaters, wetlands, and other shallow water habitats. To restore ftows that reflect the natural hydrograph of the Missouri River by the year 2008. • To inform and educate the general public and constituency about Missouri River ecosystem functions and management. To double the number of total recreational use days by the year 2008. To investigate and manage native fish, wildlife, waterfowl, and fur bearers on a sustainable basis. Even though several of these objectives fall outside of NGPC management authority, this project has and will provide the data necessary to plan, implement and evaluate them. This strategic plan is currently being reviewed and updated. Creel surveys on large rivers with numerous public and private access points are difficult and expensive to design and conduct. The first creel survey conducted on the channelized Missouri River in Nebraska was a roving creel during 1972 t01973 (Groen 1973). Segments of the channelized river covered included, Sioux City to Blair, Blair to Nebraska City and Nebraska City to Rulo. These same segments were surveyed again in 1978 and 1979 (Hesse 1980). The Missouri Department of Conservation conducted a recreational use survey on the channelized Missouri River from the mouth to the Iowa-Missouri state line in four segments over a four year period from 1983 through 1987 (Fleener 1989). The segment adjacent to Nebraska was sampled in 1985 and 1986 and extended from the lowaMissouri state line downstream to St Joseph, Missouri. The present project examining several reaches of the channelized Missouri River had several objectives: Develop a creel survey design that when repeated over time would measure changes in recreational fishing activity and success and allow us to estimate the effects of large scale restoration efforts on recreational fishing. Estimate recreational fishing use. Estimate the number and species of fish harvested and released by recreational anglers. Estimate recreational fishing effort on public and private lands and by boating anglers using public and private boat ramps Correlate fishing effort and success with a combination of season, physical habitat variables (location, macrohabitat, microhabitat, water temperature and secchi disk transparency) and fishing methods (bait) Develop recreational fishing educational information based on survey result