Securing coherence rephasing with a pair of adiabatic rapid passages

Coherence rephasing is an essential step in quantum storage protocols that use echo-based strategies. We present a thorough analysis on how two adiabatic rapid passages (ARP) are able to rephase atomic coherences in an inhomogeneously broadened ensemble. We consider both the cases of optical and spin coherences, rephased by optical or radio-frequency (rf) ARPs, respectively. We show how a rephasing sequence consisting of two ARPs in a double-echo scheme is equivalent to the identity operator (any state can be recovered), as long as certain conditions are fulfilled. Our mathematical treatment of the ARPs leads to a very simple geometrical interpretation within the Bloch sphere that permits a visual comprehension of the rephasing process. We also identify the conditions that ensure the rephasing, finding that the phase of the optical or rf ARP fields plays a key role in the capability of the sequence to preserve the phase of the superposition state. This settles a difference between optical and rf ARPs, since field phase control is not readily guaranteed in the former case. We also provide a quantitative comparison between $\pi$-pulse and ARP rephasing efficiencies, showing the superiority of the latter. We experimentally verify the conclusions of our analysis through rf ARP rephasing sequencies performed on the rare-earth ion-doped crystal Tm$^{3+}$:YAG, of interest in quantum memories.Comment: 24 pages, 7 figure

Low-mass star formation in CG1: a diffraction limited search for pre-main sequence stars next to NX Puppis

Using adaptive optics at the ESO 3.6m telescope, we obtained diffraction limited JHK-images of the region around the Herbig AeBe star NX Pup. We clearly resolved the close companion (sep. 0.128") to NX Pup -- originally discovered by HST -- and measured its JHK magnitudes. A third object at a separation of 7.0" from NX Pup was identified as a classical T Tauri star so that NX Pup may in fact form a hierarchical triple system. We discuss the evolutionary status of these stars and derive estimates for their spectral types, luminosities, masses and ages.Comment: Latex using l-aa-ps.sty with links to 5 postscript figures. Complete postscript version also available at http://lucky.astro.uni-wuerzburg.de/ Accepted for publication in A&

Austrian Social Security Database

The Austrian Social Security Database (ASSD) is a matched firm-worker data set, which records the labor market history of almost 11 million individuals from January 1972 to April 2007. Moreover, more than 2.2 million firms can be identified. The individual labor market histories are described in the follow- ing dimensions: very detailed daily labor market states and yearly earnings at the firm-worker level, together with a limited set of demographic characteris- tics. Additionally the ASSD provides some firm related information, such as geographical location and industry affiliation. This paper is a short description of this huge data base and intended for people using this data in their own empirical work.

Solitary Metastasis From Cutaneous Melanoma to the Liver: Resection by Extended Left Hepatectomy (Trisegmentectomy) With Clearance of Tumor From the Portal Vein

A 61-year-old woman presented with low grade fever and an epigastric mass eight years following resection of a stage Clark IV infraclavicular cutaneous melanoma followed by axillary node dissection. Investigations revealed a tumor in segment II, III, IV and V of the liver and a thrombus involving the main portal vein. Liver resection with extended left hepatectomy (left trisegmentectomy) and portal vein thrombectomy is reported

Effects of Hurricane-Felled Tree Trunks on Soil Carbon, Nitrogen, Microbial Biomass, and Root Length in a Wet Tropical Forest

Decaying coarse woody debris can affect the underlying soil either by augmenting nutrients that can be exploited by tree roots, or by diminishing nutrient availability through stimulation of microbial nutrient immobilization. We analyzed C, N, microbial biomass C and root length in closely paired soil samples taken under versus 20–50 cm away from large trunks of two species felled by Hugo (1989) and Georges (1998) three times during wet and dry seasons over the two years following the study conducted by Georges. Soil microbial biomass, % C and % N were significantly higher under than away from logs felled by both hurricanes (i.e., 1989 and 1998), at all sampling times and at both depths (0–10 and 10–20 cm). Frass from wood boring beetles may contribute to early effects. Root length was greater away from logs during the dry season, and under logs in the wet season. Root length was correlated with microbial biomass C, soil N and soil moisture (R = 0.36, 0.18, and 0.27, respectively; all p values < 0.05). Microbial biomass C varied significantly among seasons but differences between positions (under vs. away) were only suggestive. Microbial C was correlated with soil N (R = 0.35). Surface soil on the upslope side of the logs had significantly more N and microbial biomass, likely from accumulation of leaf litter above the logs on steep slopes. We conclude that decaying wood can provide ephemeral resources that are exploited by tree roots during some seasons

An analysis of the abuse of power by leaders in Christian organisations: cultural comparisons from Canada, Germany and South Africa

The purpose of this dissertation is to determine what constitutes the abuse of power by leaders in Christian organisations and how it can be addressed, especially in a multicultural context. The theoretical and empirical research defines the abuse of power, especially in Christian organisations, and outlines the results. It determines the role that culture plays in the abuse of power and presents strategies that can be used effectively to prevent or deal with the abuse of power in different cultural contexts in Christian organisations. The cultures considered in the empirical research are English-speaking Canadians, Germans (from what was formerly West Germany), and white South Africans. In this research, the abuse of power, the aspects that define abusive leaders and the victims, and the effects of the abuse of power on the leaders, victims and the organisations are discussed. The literature and the responses from the research participants clearly confirm the existence of abusive leadership in Christian organisations. The characteristics that constitute an ethical Christian leader are defined and underlined by the responses from the respondents in this research: spiritual transformation, love, servant leadership, accountability, trust and forgiveness. Addressing the abuse of power in Christian organisations, specifically in a multicultural context is challenging. Leaders must be prepared to learn about and understand the cultures represented in the team. They also have a responsibility to challenge their team members to reflect on their cultural characteristics, to have healthy discussions and to form an organisational third culture that profits from the potential that each team member can contribute.Philosophy, Practical and Systematic TheologyM. Th. (Christian leadership

Dietary red meat aggravates dextran sulfate sodium-induced colitis in mice whereas resistant starch attenuates inflammation

Although a genetic component has been identified as a risk factor for developing inflammatory bowel disease, there is evidence that dietary factors also play a role in the development of this disease. Aims The aim of this study was to determine the effects of feeding a red meat diet with and without resistant starch (RS) to mice with dextran sulfate sodium (DSS)-induced colitis. Methods Colonic experimental colitis was induced in Balb/c mice using DSS. The severity of colitis was evaluated based on a disease activity index (based on bodyweight loss, stool consistency, rectal bleeding, and overall condition of the animal) and a histological score. Estimations were made of numbers of a range of different bacteria in the treatment pools of cecal digesta using quantitative real-time PCR. Results Consumption of a diet high in red meat increased DSS-induced colitis as evidenced by higher disease activity and histopathological scores. Addition of RS to the red meat diet exerted a beneficial effect in acute DSS-induced colitis. Subjective analysis of numbers of a range of bacterial targets suggest changes in the gut microbiota abundance were induced by red meat and RS treatments and these changes could contribute to the reported outcomes. Conclusions A dietary intake of red meat aggravates DSS-induced colitis whereas co-consumption of resistant starch reduces the severity of colitis.This work was supported by the National Health and Medical Research Council (grant ID 535079) and CSIRO Preventative Health National Research Flagship

Accumulation of promutagenic DNA adducts in the mouse distal colon after consumption of heme does not induce colonic neoplasms in the western diet model of spontaneous colorectal cancer

Author version made available in accordance with Publisher copyright policy.Scope: Red meat is considered a risk factor for colorectal cancer (CRC). Heme is considered to promote colonic hyperproliferation and cell damage. Resistant starch (RS) is a food that ferments in the colon with studies demonstrating protective effects against CRC. By utilizing the western diet model of spontaneous CRC, we determined if feeding heme (as hemin chloride) equivalent to a high red meat diet would increase colonic DNA adducts and CRC and whether RS could abrogate such effects. Methods and results: Four groups of mice: control, heme, RS and heme + RS were fed diets for 1 or 18 months. Colons were analyzed for apoptosis, proliferation, DNA adducts “8-hydroxy-2-deoxyguanosine” and “O6-methyl-2-deoxyguanosine” (O6MeG), and neoplasms. In the short term, heme increased cell proliferation (p < 0.05). Changes from 1 to 18 months showed increased cell proliferation (p<0.01) and 8-hydroxy-2-deoxyguanosine adducts (p < 0.05) in all groups, but only heme-fed mice showed reduced apoptosis (p < 0.01) and increasedO6MeGadducts (p<0.01). The incidence of colon neoplasms was not different between any interventions. Conclusion: We identified heme to increase proliferation in the short term, inhibit apoptosis over the long term, and increase O6MeG adducts in the colon over time although these changes did not affect colonic neoplasms within this mouse model.Funding for this project was provided by the National Health and Medical Research Council of Australia (Project number 535079).We would like to acknowledge the Royal Society of Edinburgh for funding a visit for Dr. SilviaGratz fromUKto Australia to carry out work associated with this project