Cavity QED determination of atomic number statistics in optical lattices

We study the reflection of two counter-propagating modes of the light field in a ring resonator by ultracold atoms either in the Mott insulator state or in the superfluid state of an optical lattice. We obtain exact numerical results for a simple two-well model and carry out statistical calculations appropriate for the full lattice case. We find that the dynamics of the reflected light strongly depends on both the lattice spacing and the state of the matter-wave field. Depending on the lattice spacing, the light field is sensitive to various density-density correlation functions of the atoms. The light field and the atoms become strongly entangled if the latter are in a superfluid state, in which case the photon statistics typically exhibit complicated multimodal structures.Comment: 10 pages revtex, 13 figure

Non-destructive cavity QED probe of Bloch oscillations in a gas of ultracold atoms

We describe a scheme for probing a gas of ultracold atoms trapped in an optical lattice and moving in the presence of an external potential. The probe is non-destructive and uses the existing lattice fields as the measurement device. Two counter-propagating cavity fields simultaneously set up a conservative lattice potential and a weak quantum probe of the atomic motion. Balanced heterodyne detection of the probe field at the cavity output along with integration in time and across the atomic cloud yield information about the atomic dynamics in a single run. The scheme is applied to a measurement of the Bloch oscillation frequency for atoms moving in the presence of the local gravitational potential. Signal-to-noise ratios are estimated to be as high as $10^4$.Comment: 8 pages, 6 figures, submitted to Phys. Rev.

Design and Fabrication of Three-Dimensional Scaffolds for Tissue Engineering of Human Heart Valves

We developed a new fabrication technique for 3-dimensional scaffolds for tissue engineering of human heart valve tissue. A human aortic homograft was scanned with an X-ray computer tomograph. The data derived from the X-ray computed tomogram were processed by a computer-aided design program to reconstruct a human heart valve 3-dimensionally. Based on this stereolithographic model, a silicone valve model resembling a human aortic valve was generated. By taking advantage of the thermoplastic properties of polyglycolic acid as scaffold material, we molded a 3-dimensional scaffold for tissue engineering of human heart valves. The valve scaffold showed a deviation of only +/- 3-4% in height, length and inner diameter compared with the homograft. The newly developed technique allows fabricating custom-made, patient-specific polymeric cardiovascular scaffolds for tissue engineering without requiring any suture materials. Copyright (c) 2008 S. Karger AG, Base

Portrayal of psychiatric genetics in Australian print news media, 1996-2009

Objective: To investigate how Australian print news media portray psychiatric genetics. Design and setting: Content and framing analysis of a structured sample of print news items about psychiatric genetics published in Australian newspapers between 1996 and 2009. Main outcome measures: Identify dominant discourses about aetiology of mental illness, and perceived clinical outcomes and implications of psychiatric genetics research. Results: We analysed 406 eligible items about the genetics of psychiatric disorders. News coverage of psychiatric genetics has steadily increased since 1996. Items attributing the aetiology of psychiatric disorders to gene-environment interactions (51%) outnumbered items attributing only genetic (30%) or only environmental factors (20%). Of items that referred to heritability of mental illness, frames of genetic determinism (78%) occurred more frequently than probabilistic frames (22%). Of frames related to genetic prophesy, genetic optimism frames (78%) were used more frequently than frames of genetic pessimism (22%). Psychosocial and ethical implications of psychiatric genetics received comparatively relatively little coverage (23%). The analysis identified 22 predictions about psychiatric genetic discoveries and the availability of molecular-based interventions in psychiatry, most of which (20/ 22, 91%) failed to manifest by the predicted year. Conclusions: Excessive optimism about the power of genetic technology in psychiatric health care, perceived clinical benefits, and largely unfulfilled predictions about availability of these benefits could encourage unrealistic expectations about future molecular-based treatment options for mental health

Active optical clock based on four-level quantum system

Active optical clock, a new conception of atomic clock, has been proposed recently. In this report, we propose a scheme of active optical clock based on four-level quantum system. The final accuracy and stability of two-level quantum system are limited by second-order Doppler shift of thermal atomic beam. To three-level quantum system, they are mainly limited by light shift of pumping laser field. These limitations can be avoided effectively by applying the scheme proposed here. Rubidium atom four-level quantum system, as a typical example, is discussed in this paper. The population inversion between $6S_{1/2}$ and $5P_{3/2}$ states can be built up at a time scale of $10^{-6}$s. With the mechanism of active optical clock, in which the cavity mode linewidth is much wider than that of the laser gain profile, it can output a laser with quantum-limited linewidth narrower than 1 Hz in theory. An experimental configuration is designed to realize this active optical clock.Comment: 5 page

Exploration of decision-making regarding the transfer of mosaic embryos following preimplantation genetic testing: A qualitative study

STUDY QUESTION: What are patients' reasoning and decisional needs in relation to the transfer of mosaic embryos following preimplantation genetic testing (PGT)? SUMMARY ANSWER: This study identified four themes, which were patients' reasoning behind decision-making, their decisional needs, the influence of the mosaic embryos on the decision-making and the role of health professionals. WHAT IS KNOWN ALREADY: To date, no study has investigated the reasoning of patients behind their decision-making and the influence of mosaic embryos. STUDY DESIGN, SIZE, DURATION: This is a cross-sectional study using a qualitative approach. Twenty participants were interviewed, and recruitment was ceased when no new information was identified in the data analysis. It ensured a sufficient sample size for a qualitative study. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were females with mosaic embryos. Semi-structured in-depth interviews were conducted via telephone. MAIN RESULTS AND THE ROLE OF CHANCE: Four themes were identified: Reasoning behind decision-making, decisional needs, influence of mosaic embryos on decision-making and the role of health professionals. Potential risks of transferring mosaic embryos and prioritization of euploid embryos were the main reasons for not transferring mosaic embryos. A lack of alternatives, perceived benefits and risk tolerance were main reasons for transferring mosaic embryos. Patients reported that information on mosaic embryos, amniocentesis and termination was important to support their decision-making. Unmet needs relating to healthcare services and social support were reported. In addition, having mosaic embryos affected the patients' emotional and behavioural responses, discussions about prenatal testing, attitudes to termination and further IVF cycles and attitudes towards PGT. Health professionals were found to influence the patients' decision-making. LIMITATIONS, REASONS FOR CAUTION: Participants were recruited through one clinic, which may limit the transferability of results. Also, patients' experiences in relation to financial aspects of PGT may not be relevant to other jurisdictions due to different healthcare policies. WIDER IMPLICATIONS OF THE FINDINGS: The results may inform how clinicians provide healthcare services based on factors influencing patients' decision-making. Health professionals should be aware of the influence their attitudes can have on patients' decision-making and should present information accordingly. Also, providing all relevant information may help to facilitate informed decision-making. Provision of psychological support from professionals and support groups is also critical during the process of testing and transfer. Patients have educational needs regarding mosaic embryos, and educational resources including decision aids in plain language are needed. STUDY FUNDING/COMPETING INTEREST(S): B.M. was funded through a Senior Research Fellowship Level B (ID 1078523) from the National Health and Medical Research Council of Australia. L.C. was supported by a University International Postgraduate Award under the Australian Government Research Training Program (RTP) scholarship. No other funding was received for this study. The authors report no competing interests. TRIAL REGISTRATION NUMBER: N/A

Cohort profile: mental health following extreme trauma in a northern Ugandan cohort of War-Affected Youth Study (The WAYS Study).

War experiences are associated with the risk of long-term mental health problems. The War-affected Youths (WAYS) Study comprises a cohort of 539 youths (61% female) aged between 18 to 25 (at baseline) randomly sampled from the population of war-affected youths in northern Uganda. The study aims to chart the trajectory of long-term mental health consequences of war and the roles of individual, family, and community contextual risk and protective factors in influencing the course of mental health using Social Ecology Model, thus, addressing both the individual and its social ecology. Knowledge of postwar contexts may inform policy and guide interventions on postwar psychosocial adjustment and reintegration in conflict-prone Great Lakes region of Africa (Rwanda, Burundi, DR Congo, Uganda, Central African Republic, and South Sudan). Two waves of data collection have been conducted and more data collection is planned. At baseline, information on demographic characteristics, pre-war experiences, psychosocial outcomes, coping, stigma/discrimination, family and community acceptance and relationship, family functioning, and post-war experiences were obtained. At follow-up, information on general health, gender-based violence, PTSD, social skills, trauma memory quality, rumination, self-esteem, and psychosocial outcomes were collected. Approval to access the data can be obtained on application to the Principal Investigator upon submission of a research proposal with ethical approval from the applicant's institution. This research is funded by Wellcome Trust and Gulu University.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are