Spontaneous, collective coherence in driven, dissipative cavity arrays

We study an array of dissipative tunnel-coupled cavities, each interacting with an incoherently pumped two-level emitter. For cavities in the lasing regime, we find correlations between the light fields of distant cavities, despite the dissipation and the incoherent nature of the pumping mechanism. These correlations decay exponentially with distance for arrays in any dimension but become increasingly long ranged with increasing photon tunneling between adjacent cavities. The interaction-dominated and the tunneling-dominated regimes show markedly different scaling of the correlation length which always remains finite due to the finite photon trapping time. We propose a series of observables to characterize the spontaneous build-up of collective coherence in the system.Comment: 9 pages, 4 figures, including supplemental material (with 4 pages, 1 figure). This is a shorter version with some modifications in the supplemental material (a gap in the proof was closed and calculations significantly generalized and improved

A longitudinal study of the bi-directional relationship between tobacco smoking and psychological distress in a community sample of young Australian women

Background. Tobacco smoking and poor mental health are both prevalent and detrimental health problems in young women. The temporal relationship between the two variables is unclear. We investigated the prospective bidirectional relationship between smoking and mental health over 13 years

Agricultural Research at the Antelope Range Field Station: A Progress Report

South Dakota State College research workers, with the help of the Field Station Advisory Council and the cooperation of the South Dakota Department of Game, Fish, and Parks, began planning and establishing experimental projects at the Antelope Range Field Station in 1947. The Range Station consists of 7,920 acres of range Janel in east-central Harding County. A large part of this tract, 6,680 acres, is under the control of the state office of School and Public Lands; 1,120 acres are owned by the Department of Game, Fish and Parks; and 120 acres are privately owned by a neighbor. Prior to 1946 the preserve area was leased for grazing to private interests. The 1957 Legislature authorized the exchange of the 1,120 acres owned by the Game, Fish and Parks Department for School and Public Lands located elsewhere in the state. Negotiations to accomplish the land exchange are in progress at the time of this writing. The station lies 2 miles south of Highway No. 8 on the west side of the Slim Buttes. The land is rolling prairie, deeply cut in some places by intermittent streams, and unsuitable for most agricultural purposes except grazing. This area was originally organized as an antelope preserve and for many years was operated as such under the control of the Game, Fish and Parks Department. In the fall of 1946, at the request of livestock men of western South Dakota, representing the Western South Dakota Sheep Growers\u27 Association, the Cooperative wool Growers\u27 of South Dakota, the Black Hills\u27 Protective Association, Harding County Livestock Improvement Association, South Dakota Purebred Sheep Breeders Association, and the South Dakota Stockgrowers\u27 Association, the Game, Fish and Parks Commission entered into an agreement to permit the South Dakota State College Agricultural Experiment Station to use the Antelope Range Preserve as a livestock experiment field station for range research in problems dealing with beef cattle, sheep, and antelope. Representatives of the organizations formed an advisory council to assist in developing the station and suggesting problems that needed research study. The orginal advisory committee and the animal husbandry department research men compiled a list of 21 major problems that would be suitable for development at the Antelope Range Field Station, although not all of these could be handled at once. Actual research work was started in 1947. The first experimental livestock with which the ranch was stocked were sheep, but within the first year a cow herd was added. Of the 21 problems suggested, parasitism in sheep, stocking rate and rotational grazing studies with sheep, supplements for wintering pregnant ewes, and beef cattle breeding research were the ones undertaken and upon which sufficient data have been collected to warrant publication of the results. Many of these studies are still underway. One of the early goals was to discover basic information on compatibility of sheep and antelope grazing on the same range in respect to carrying capacity of the range, parasites common to both species, and the host parasite interrelationships. Unfortunately this work has yielded little information because of difficulties in handling antelope either in captivity or under controlled conditions on range pastures. The other experiments have been carried forward and the results to date are reported in this bulletin

Traffic Network Optimum Principle - Minimum Probability of Congestion Occurrence

We introduce an optimum principle for a vehicular traffic network with road bottlenecks. This network breakdown minimization (BM) principle states that the network optimum is reached, when link flow rates are assigned in the network in such a way that the probability for spontaneous occurrence of traffic breakdown at one of the network bottlenecks during a given observation time reaches the minimum possible value. Based on numerical simulations with a stochastic three-phase traffic flow model, we show that in comparison to the well-known Wardrop's principles the application of the BM principle permits considerably greater network inflow rates at which no traffic breakdown occurs and, therefore, free flow remains in the whole network.Comment: 22 pages, 6 figure

A MODEL OF COMPETITIVENESS IN INTANGIBLE CULTURAL HERITAGE TOURISM DESTINATIONS FROM THE KNOWLEDGE-BASED VIEW

U ovom radu predstavljen je model nematerijalne kulturne baštine sa stajališta temeljenog na znanju kojim se proučava njezina uloga u konkurentnosti destinacije. Prvo se razmatra pojam nematerijalne kulturne baštine i njen odnos s turizmom. Zatim slijedi osvrt na značaj konkurentnosti destinacije u kontekstu nematerijalne baštine i potencijala koji će se analizirati u okviru stajališta temeljenog na znanju. Kako je pojam održive konkurentske prednosti ključan u tom okruženju, važno je raspraviti odnose oskudnosti, relevantnosti, autentičnosti vezane uz mjesto, kratkoročne zaštite i prijenosa inherentnog znanja o nematerijalnoj kulturnoj baštini. Na prednostima održivog razvoja temeljenim na nematerijalnoj kulturnoj baštini zasniva se generiranje renti, ali one bi trebale barem djelomično pripadati lokalnoj zajednici/glavnim dionicima u destinaciji.This work presents a model of intangible cultural heritage from a knowledge-based view that studies its role in destination competitiveness. Firstly, the concept of intangible cultural heritage and its relationship with tourism are reviewed. Next, the importance of destination competitiveness in the intangible heritage context and the potential to be analyzed under the framework of the knowledge-based view are addressed. As the concept of sustainable competitive advantage is key in that setting, the conditions of scarcity, relevance, place-embedded authenticity, short-term protection, and transfer of the underlying knowledge of intangible cultural heritage are discussed. Intangible cultural heritage-based sustainable competitive advantages are the basis to generate rents, but those rents should be at least partially appropriated by the local community/key stakeholders at the destination

Optical Phonon Lasing in Semiconductor Double Quantum Dots

We propose optical phonon lasing for a double quantum dot (DQD) fabricated in a semiconductor substrate. We show that the DQD is weakly coupled to only two LO phonon modes that act as a natural cavity. The lasing occurs for pumping the DQD via electronic tunneling at rates much higher than the phonon decay rate, whereas an antibunching of phonon emission is observed in the opposite regime of slow tunneling. Both effects disappear with an effective thermalization induced by the Franck-Condon effect in a DQD fabricated in a carbon nanotube with a strong electron-phonon coupling.Comment: 8 pages, 4 figure

Challenging the negative images of Haiti at a pre-visit stage using visual online learning materials

Post-conflict destinations can struggle to attract visitors because of their negative image. Research addressing this remains limited. The same can be said about the education of tourists. This research paper contributes to the literature in both areas as it examines the proposition that the education of tourists at a pre-visit stage using online, game-based material could be effective in challenging the negative perception of these destinations. From a destination management point of view, this paper offers an alternative to existing promotional material as there is little evidence at the moment that existing strategies are effective. From a conceptual point of view, this paper contributes to the very limited academic research in Gamification by adding the fact that Gamification can be a very efficient tryvertising tool if using subtle and implicit marketing elements

Recovering and Exploiting Aragonite and Calcite Single Crystals with Biologically Controlled Shapes from Mussel Shells

Control over the shape and morphology of single crystals is a theme of great interest in fundamental science and for technological application. Many synthetic strategies to achieve this goal are inspired by biomineralization processes. Indeed, organisms are able to produce crystals with high fidelity in shape and morphology utilizing macromolecules that act as modifiers. An alternative strategy can be the recovery of crystals from biomineralization products, in this case, seashells. In particular, waste mussel shells from aquaculture are considered. They are mainly built up of single crystals of calcite fibers and aragonite tablets forming an outer and an inner layer, respectively. A simple mechanochemical treatment has been developed to separate and recover these two typologies of single crystals. The characterization of these single crystals showed peculiar properties with respect to the calcium carbonate from quarry or synthesis. We exploited these biomaterials in the water remediation field using them as substrate adsorbing dyes. We found that these substrates show a high capability of adsorption for anionic dye, such as Eosin Y, but a low capability of adsorption for cationic dyes, such as Blue Methylene. The adsorption was reversible at pH 5.6. This application represents just an example of the potential use of these biogenic single crystals. We also envision potential applications as reinforcing fillers and optical devices

First measurements at the DAΦNE φ-factory with the DEAR experimental setup

The relevant background for the DEAR experiment } low-energy X rays and ionizing particles } present in the DEAR interaction region of the DA'NE e'e~ collider was investigated using the "rst-stage DEAR setup and CCD detectors. An extensive Monte Carlo simulation was performed for the present setup and beam conditions. Good quantitative agreement between measurements and simulation was achieved. This is a con"rmation that, with respect to the expected background, which gives an important contribution to the statistical precision of the experiment, the con"guration chosen to measure the strong interaction shift and width in kaonic hydrogen and kaonic deuterium can indeed reach the planned level of accuracy. ( 2000 Elsevier Science B.V. All rights reserved