Nonlinear Transformation for a Class of Gauged Schroedinger Equations with Complex Nonlinearities

In the present contribution we consider a class of Schroedinger equations containing complex nonlinearities, describing systems with conserved norm $|\psi|^2$ and minimally coupled to an abelian gauge field. We introduce a nonlinear transformation which permits the linearization of the source term in the evolution equations for the gauge field, and transforms the nonlinear Schroedinger equations in another one with real nonlinearities. We show that this transformation can be performed either on the gauge field $A_\mu$ or, equivalently, on the matter field $\psi$. Since the transformation does not change the quantities $|\psi|^2$ and $F_{\mu\nu}$, it can be considered a generalization of the gauge transformation of third kind introduced some years ago by other authors. Pacs numbers: 03.65.-w, 11.15.-qComment: 4pages, two columns, RevTeX4, no figure

Irish Travel, Vol 27 (1951-52)

https://arrow.tudublin.ie/irtourjap/1026/thumbnail.jp

Foreign Travel

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An exploratory study on consumer travel agency information sources: an Australian regional analysis

[Abstract]: The research reported in this paper explores why regional consumers choose to book their travel arrangements with travel agencies. Consumers can now access on-line bookings for airlines, accommodation, transportation, sightseeing tours and other related products so why do they still go to travel agencies for reservations? This paper identifies the information sources consumers used when selecting a travel agency. The research design involves two stages. The first stage has been completed and was a series of in-depth interviews with 10 users of regional travel agencies and three experienced travel agency consultants. The second stage will be a mail-out survey to travel agencies in the Darling Downs area of Queensland, Australia. Despite its locality, the region is a significant consumer of travel with approximately eight retail travel agencies in the city of Toowoomba alone. The in-depth interviews highlighted the need to de-emphasize three particular information sources considered for inclusion in the survey for stage two. They were, travel guidebooks, travel or automotive clubs and local travel offices which were deleted from the intended survey and replaced with television lifestyle programs as an information source worthy of investigation

Causal Loops in Time Travel

About the possibility of time traveling based on several specialized works, including those of Nicholas J. J. Smith ("Time Travel"), William Grey (”Troubles with Time Travel”), Ulrich Meyer (”Explaining causal loops”), Simon Keller and Michael Nelson (”Presentists should believe in time-travel”), Frank Arntzenius and Tim Maudlin ("Time Travel and Modern Physics"), and David Lewis (“The Paradoxes of Time Travel”). The article begins with an Introduction in which I make a short presentation of the time travel, and continues with a History of the concept of time travel, main physical aspects of time travel, including backward time travel in the past in general relativity and quantum physics, and time travel in the future, then a presentation of the Grandfather paradox that is approached in almost all specialized works, followed by a section dedicated to the Philosophy of time travel, and a section in which I analyze Causal loops for time travel. I finish my work with Conclusions, in which I sustain my personal opinions on the time travel, and the Bibliography on which the work is based

Self-reported illness among Boston-area international travelers: A prospective study

This is the Accepted Manuscript version and was published in final edited form as: Travel Med Infect Dis. 2016 ; 14(6): 604–613. doi:10.1016/j.tmaid.2016.09.009.BACKGROUND: The Boston Area Travel Medicine Network surveyed travelers on travel-related health problems. METHODS: Travelers were recruited 2009-2011 during pre-travel consultation at three clinics. The investigation included pre-travel data, weekly during-travel diaries, and a post-travel questionnaire. We analyzed demographics, trip characteristics, health problems experienced, and assessed the relationship between influenza vaccination, influenza prevention advice, and respiratory symptoms. RESULTS:Of 987 enrolled travelers, 628 (64%) completed all surveys, of which 400 (64%) reported health problems during and/or after travel; median trip duration was 12 days. Diarrhea affected the most people during travel (172) while runny/stuffy nose affected the most people after travel (95). Of those with health problems during travel, 25% stopped or altered plans; 1% were hospitalized. After travel, 21% stopped planned activities, 23% sought physician or other health advice; one traveler was hospitalized. Travelers who received influenza vaccination and influenza prevention advice had lower rates of respiratory symptoms than those that received influenza prevention advice alone (18% vs 28%, P = 0.03). CONCLUSIONS:A large proportion of Boston-area travelers reported health problems despite pre-travel consultation, resulting in inconveniences. The combination of influenza prevention advice and influenza immunization was associated with fewer respiratory symptoms than those who received influenza prevention advice alone