Quantum tunneling dynamics of an interacting Bose-Einstein condensate through a Gaussian barrier

The transmission of an interacting Bose-Einstein condensate incident on a repulsive Gaussian barrier is investigated through numerical simulation. The dynamics associated with interatomic interactions are studied across a broad parameter range not previously explored. Effective 1D Gross-Pitaevskii equation (GPE) simulations are compared to classical Boltzmann-Vlasov equation (BVE) simulations in order to isolate purely coherent matterwave effects. Quantum tunneling is then defined as the portion of the GPE transmission not described by the classical BVE. An exponential dependence of transmission on barrier height is observed in the purely classical simulation, suggesting that observing such exponential dependence is not a sufficient condition for quantum tunneling. Furthermore, the transmission is found to be predominately described by classical effects, although interatomic interactions are shown to modify the magnitude of the quantum tunneling. Interactions are also seen to affect the amount of classical transmission, producing transmission in regions where the non-interacting equivalent has none. This theoretical investigation clarifies the contribution quantum tunneling makes to overall transmission in many-particle interacting systems, potentially informing future tunneling experiments with ultracold atoms.Comment: Close to the published versio

A Bose-condensed, simultaneous dual species Mach-Zehnder atom interferometer

This paper presents the first realisation of a simultaneous $^{87}$Rb -$^{85}$Rb Mach-Zehnder atom interferometer with Bose-condensed atoms. A number of ambitious proposals for precise terrestrial and space based tests of the Weak Equivalence Principle rely on such a system. This implementation utilises hybrid magnetic-optical trapping to produce spatially overlapped condensates with a duty cycle of 20s. A horizontal optical waveguide with co-linear Bragg beamsplitters and mirrors is used to simultaneously address both isotopes in the interferometer. We observe a non-linear phase shift on a non-interacting $^{85}$Rb interferometer as a function of interferometer time, $T$, which we show arises from inter-isotope scattering with the co-incident $^{87}$Rb interferometer. A discussion of implications for future experiments is given.Comment: 7 pages, 5 figures. The authors welcome comments and feedback on this manuscrip

Perancangan Buku Komik City Guide Pariwisata Kota Surabaya Berbasis Ilustrasi Digital Guna Menganalkan Wisata Surabaya

The purpose of the design a comic book City Surabaya tourism guide is to introduce and promote tourism. Further research is done using qualitative research methodsthat do interviews, observation, and literature to obtain data that is used in the creation of design concepts to support the comic book city Surabaya tourism guide. The data were analyzed by using multiple stage, apply the reduction of data, data presentation, and conclusion. After analyzing the data, the found discuss the design concepts or keywords "Modern". The complaint is the latest, cutting edge, attitude andway of thinking and acting in accordance with the demands of the times. The concept of "Modern" aims to show that Surabaya is a city that has developed technology.Acting, the concept of the menu-the menu is served to infuse the public perceptionthat the public Surabaya willing to learn and thrive in the new stuff. The result of designing a comic book City of Surabaya tourism guide is to introduce and promote tourism city of Surabaya Surabaya and so that people outside the city could've known tourism in Surabaya

Translation of findings from laboratory studies of food and alcohol intake into behavior change interventions : the experimental medicine approach.

Objectives: Laboratory studies have contributed important information about the determinants of food and alcohol intake, and they have prompted the development of behavior change interventions that have been evaluated in randomized controlled trials conducted in the field. In this article we apply a recent experimental medicine (EM) framework to this body of research. Method: A conceptual review and focused discussion of the relevant literature is presented. Results: We illustrate how it is possible to translate findings from studies of food and alcohol intake in the laboratory into interventions that are effective for changing behavior in the real world. We go on to demonstrate how systematic failures can occur at different stages within the EM framework, and how these failures ultimately result in interventions that are ineffective for changing behavior. We also consider methodological issues that may constrain the external validity of findings from laboratory studies including demand effects, participant characteristics, and the timing and dose of behavioral interventions. Throughout, we make recommendations to improve the translation of findings from laboratory studies into behavior change interventions that are effective in the field. Conclusions: Consideration of the EM framework will help to ensure that promising candidate interventions for eating and drinking that are identified in laboratory studies can fulfill their translational promise

Believing in food addiction: helpful or counter-productive for eating behaviour?

Objective: Obesity is often attributed to an addiction to food, and many people believe themselves to be “food addicts.” However, little is known about how such beliefs may affect dietary control and weight management. The current research examined the impact of experimentally manipulating participants' personal food addiction beliefs on eating behavior. Methods In two studies, female participants (study 1: N  = 64; study 2: N  = 90) completed food‐related computerized tasks and were given bogus feedback on their performance which indicated that they had high, low, or average food addiction tendencies. Food intake was then assessed in an ad libitum taste test. Dietary concern and time taken to complete the taste test were recorded in study 2. Results: In study 1, participants in the high‐addiction condition consumed fewer calories than those in the low‐addiction condition, F (1,60) = 7.61, P  = 0.008, η p2 = 0.11. Study 2 replicated and extended this finding, showing that the effect of the high‐addiction condition on food intake was mediated by increased dietary concern, which reduced the amount of time participants willingly spent exposed to the foods during the taste test, b  = −0.06 (0.03), 95% confidence interval = −0.13 to −0.01. Conclusions: Believing oneself to be a food addict is associated with short‐term dietary restriction. The longer‐term effects on weight management now warrant attention

Optically guided linear Mach Zehnder atom interferometer

We demonstrate a horizontal, linearly guided Mach Zehnder atom interferometer in an optical waveguide. Intended as a proof-of-principle experiment, the interferometer utilises a Bose-Einstein condensate in the magnetically insensitive |F=1,mF=0> state of Rubidium-87 as an acceleration sensitive test mass. We achieve a modest sensitivity to acceleration of da = 7x10^-4 m/s^2. Our fringe visibility is as high as 38% in this optically guided atom interferometer. We observe a time-of-flight in the waveguide of over half a second, demonstrating the utility of our optical guide for future sensors.Comment: 6 pages, 3 figures. Submitted to Phys. Rev.

Suppression of Implanted MDA-MB 231 Human Breast Cancer Growth in Nude Mice by Dietary Walnut

Walnuts contain components that may slow cancer growth including omega 3 fatty acids, phytosterols, polyphenols, carotenoids, and melatonin. A pilot study was performed to determine whether consumption of walnuts could affect growth of MDA-MB 231 human breast cancers implanted into nude mice. Tumor cells were injected into nude mice that were consuming an AIN-76A diet slightly modified to contain 10% corn oil. After the tumors reached 3 to 5 mm diameter, the diet of one group of mice was changed to include ground walnuts, equivalent to 56 g (2 oz) per day in humans. The tumor growth rate from Day 10, when tumor sizes began to diverge, until the end of the study of the group that consumed walnuts (2.9 ± 1.1 mm3/day; mean ± standard error of the mean) was significantly less (P \u3e 0.05, t-test of the growth rates) than that of the group that did not consume walnuts (14.6 ± 1.3 mm 3 /day). The eicosapentaenoic and docosahexaenoic acid fractions of the livers of the group that consumed walnuts were significantly higher than that of the group that did not consume walnuts. Tumor cell proliferation was decreased, but apoptosis was not altered due to walnut consumption. Further work is merited to investigate applications to cancer in humans

Editorial Introduction: Praxeological Gestalts – Philosophy, Cognitive Science and Sociology Meet Gestalt Psychology.

The idea for the current issue of Philosophia Scientiæ emerged from discussions which took place in the Manchester Ethnomethodology Reading Group. This reading group has its origins in Wes Sharrock’s weekly discussion groups, which have taken place in Manchester (UK) since the early 1970s. As the global Covid-19 pandemic hit in early 2020, the reading group moved online, facilitated by Phil Hutchinson and Alex Holder. Being an online reading group opened up participation to people beyond Northwest UK and within weeks the group became global, with the membership including participants logging on from Canada, Czech Republic, Finland, France, Germany, Greece, Hong Kong, Japan, Macau, New Zealand, Spain, Sweden, and the USA. While the name of the group might indicate an exclusive focus on ethnomethodology, following the naming conventions for academic discussion groups, the name really fails to indicate both the heterogeneity of the group’s reading materials, the interests of the participants, and the disciplinary affiliations of the group’s membership. Members of the group are drawn from anthropology, criminology, education, geography, linguistics, philosophy, psychology, sociology, science and technology studies, and beyond. The readings discussed range from work in the ethnomethodological tradition, including Conversation Analysis (EMCA); philosophy, with particular focus on phenomenology and Wittgensteinian thought; and metaphilosophical and methodological texts

Observation of a Modulational Instability in Bose-Einstein condensates

We observe the breakup dynamics of an elongated cloud of condensed $^{85}$Rb atoms placed in an optical waveguide. The number of localized spatial components observed in the breakup is compared with the number of solitons predicted by a plane-wave stability analysis of the nonpolynomial nonlinear Schr\"odinger equation, an effective one-dimensional approximation of the Gross-Pitaevskii equation for cigar-shaped condensates. It is shown that the numbers predicted from the fastest growing sidebands are consistent with the experimental data, suggesting that modulational instability is the key underlying physical mechanism driving the breakup.Comment: 6 pages, 5 figure