Coherent adiabatic transport of atoms in radio-frequency traps

Coherent transport by adiabatic passage has recently been suggested as a high-fidelity technique to engineer the center-of-mass state of single atoms in inhomogeneous environments. While the basic theory behind this process is well understood, several conceptual challenges for its experimental observation have still to be addressed. One of these is the difficulty that currently available optical or magnetic micro-trap systems have in adjusting the tunneling rate time dependently while keeping resonance between the asymptotic trapping states at all times. Here we suggest that both requirements can be fulfilled to a very high degree in an experimentally realistic setup based on radio-frequency traps on atom chips. We show that operations with close to 100% fidelity can be achieved and that these systems also allow significant improvements for performing adiabatic passage with interacting atomic clouds

Candidate selection and instance ordering for realtime algorithm configuration

Many modern combinatorial solvers have a variety of parameters through which a user can customise their behaviour. Algorithm configuration is the process of selecting good values for these parameters in order to improve performance. Time and again algorithm configuration has been shown to significantly improve the performance of many algorithms for solving challenging computational problems. Automated systems for tuning parameters regularly out-perform human experts, sometimes but orders of magnitude. Online algorithm configurators, such as ReACTR, are able to tune a solver online without incurring costly offline training. As such ReACTR’s main focus is on runtime minimisation while solving combinatorial problems. To do this ReACTR adopts a one-pass methodology where each instance in a stream of instances to be solved is considered only as it arrives. As such ReACTR’s performance is sensitive to the order in which instances arrive. It is still not understood which instance orderings positively or negatively effect the performance of ReACTR. This paper investigates the effect of instance ordering and grouping by empirically evaluating different instance orderings based on difficulty and feature values. Though the end use is generally unable to control the order in which instances arrive it is important to understand which orderings impact Re- ACTR’s performance and to what extent. This study also has practical benefit as such orderings can occur organically. For example as business grows the problems it may encounter, such as routing or scheduling, often grow in size and difficulty. ReACTR’s performance also depends strongly configuration selection procedure used. This component controls which configurations are selected to run in parallel from the internal configuration pool. This paper evaluates various ranking mechanisms and different ways of combining them to better understand how the candidate selection procedure affects realtime algorithm configuration. We show that certain selection procedures are superior to others and that the order which instances arrive in determines which selection procedure performs best. We find that both instance order and grouping can significantly affect the overall solving time of the online automatic algorithm configurator ReACTR. One of the more surprising discoveries is that having groupings of similar instances can actually negatively impact on the overall performance of the configurator. In particular we show that orderings based on nearly any instance feature values can lead to significant reductions in total runtime over random instance orderings. In addition, certain candidate selection procedures are more suited to certain orderings than others and selecting the correct one can show a marked improvement in solving times

Coherent transport by adiabatic passage on atom chips

Adiabatic techniques offer some of the most promising tools for achieving high-fidelity control of the center-of-mass degree of freedom of single atoms. Because the main requirement of these techniques is to follow an eigenstate of the system, constraints on timing and field strength stability are usually low, especially for trapped systems. In this paper we present a detailed example of a technique to adiabatically transport a single atom between different waveguides on an atom chip. To ensure that all conditions are fulfilled, we carry out fully three-dimensional simulations of the system, using experimentally realistic parameters. We also detail our method for simulating the system in very reasonable time scales on a consumer desktop machine by leveraging the power of graphics-processing-unit computing

A plasmid-encoded putative glycosyltransferase is involved in hop tolerance and beer spoilage in Lactobacillus brevis

Lactobacillus brevis beer-spoiling strains harbor plasmids that contain genes such as horA, horC, and hitA which are known to confer hop tolerance. The L. brevis beer-spoiling strain UCCLBBS124, which possesses four plasmids, was treated with novobiocin, resulting in the isolation of UCCLBBS124 derivatives exhibiting hop sensitivity and an inability to grow in beer. One selected derivative was shown to have lost a single plasmid, here designated UCCLBBS124_D, which harbors the UCCLBBS124_pD0015 gene, predicted to encode a glycosyltransferase. Hop tolerance and growth in beer were restored when UCCLBBS124_pD0015 was introduced in one of these hop-sensitive derivatives on a plasmid. We hypothesize that this gene modifies the surface composition of the polysaccharide cell wall, conferring protection against hop compounds. Furthermore, the introduction of this gene in trans in L. brevis UCCLB521, a strain that cannot grow in and spoil beer, was shown to furnish the resulting strain with the ability to grow in beer, while its expression also conferred phage resistance. This study underscores how the acquisition of certain mobile genetic elements plays a role in hop tolerance and beer spoilage for strains of this bacterial species.IMPORTANCELactobacillus brevis is a member of the lactic acid bacteria and is often reported as the causative agent of food or beverage spoilage, in particular, that of beer. Bacterial spoilage of beer may result in product withdrawal or recall, with concomitant economic losses for the brewing industry. A very limited number of genes involved in beer spoilage have been identified and primarily include those involved in hop resistance, such as horA, hitA, and horC However, since none of these genes are universal, it is clear that there are likely (many) other molecular players involved in beer spoilage. Here, we report on the importance of a plasmid-encoded glycosyltransferase associated with beer spoilage by L. brevis that is involved in hop tolerance. The study highlights the complexity of the genetic requirements to facilitate beer spoilage and the role of multiple key players in this process

Biodiversity and classification of phages infecting Lactobacillus brevis

Lactobacillus brevis is a lactic acid bacterium that is known as a food and beverage spoilage organism, and more specifically as a beer-spoiler. Phages of L. brevis have been described, but very limited data is available regarding temperate phages of L. brevis. Temperate phages may exert benefits to the host, while they may also be employed to combat beer spoilage. The current study reports on the incidence of prophage sequences present in nineteen distinct L. brevis genomes. Prophage induction was evaluated using mitomycin C exposure followed by genome targeted-PCR, electron microscopy and structural proteome analysis. The morphological and genome sequence analyses revealed significant diversity among L. brevis prophages, which appear to be dominated by members of the Myoviridae phage family. Based on this analysis, we propose a classification of L. brevis phages into five groups

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Visualization and quantification of HIV associated lipodystrophy from magnetic resonance images

PurposeThis research aimed at developing a software tool for the purposes of quantifying andvisualizing HIV-associated lipodystrophy from full body magnetic resonance imaging(MRI) datasets. The primary goal for developing the software tool was to create andcompare the results gathered from MRI to those from the current gold standard, dualenergy X-ray absorptiometry (DEXA). A software based solution for this purpose isproposed and a full evaluation with the intention of future clinical use is presented. Theadditional aim of volume visualization in order to assess the external morphologicaleffects of HIV-associated lipodystrophy is also presented.MethodsThe data gathered for this study involved a cohort of HIV positive cases (n = 8) whichwere recruited in order to be scanned by both Dual Energy X-ray Absorptiometry(DEXA) and MRI techniques to facilitate comparison between the two modalities.The accurate identification and segmentation of adipose tissue from MRI datasets wasidentified as one the key components of this piece of research. A fully automaticsegmentation algorithm was implemented for this purpose. Quantification of segmentedadipose tissue and surface based volume visualization were implemented as the primary features of the software tool.The fully automatic segmentation algorithm was investigated in regards to accuracy andperformance. In order to evaluate the clinical relevance of the results of segmentation, acomparison of the results to those of the current gold standard (DEXA) was performed.Clinical feedback regarding the usefulness of the software tool in a clinical setting is alsopresented.Visualization of adipose distribution and external morphology from full body data werealso identified as an important component of this project. A surface based volumevisualization technique was implemented in order to allow users to view a patient’sexternal morphology. Application of a heat map to the surface in order to intuitivelyvisualize the distribution of adipose tissue was also implemented.ResultsThe findings of this study indicate that the results gathered by the software tooldeveloped compared well to those of the current gold standard. A strong correlationbetween the results of the two modalities was found with a correlation coefficient r of0.68 and significance level of p < 0.0001 with a very small 95% confidence interval. Areasonable level of agreement between the modalities was also recorded, the meandifference in fat measurements between the two was 5.62%. A panel of MR experts,Radiology (n = 2), MSc MRI Radiography Specialists (n = 3), PhD Medical ImagingMRI Specialists (n = 2) evaluated the segmentation technique used and it was found to be accurate and, due to the fact it was automatic, its results were 100% reproducible.ConclusionsIn this study the segmentation, quantification and visualization of adipose tissue from fullbody MRI dataset in place of the current gold standards was targeted and investigated.A proof of concept software tool was developed for this purpose and was evaluated foraccuracy and clinical relevance. The findings presented provide the evidence base that an appropriate tool was developed and could be used with MRI as an alternative to DEXA examination

Joseph Morrison Skelly with a foreword by President Mary Robinson : Irish Diplomacy at the United Nations, 1945-1965

O'Sullivan Tadhg F. Joseph Morrison Skelly with a foreword by President Mary Robinson : Irish Diplomacy at the United Nations, 1945-1965. In: Études irlandaises, n°23-1, 1998. pp. 237-238

The Impossible Diplomatic Mission of Battista Rinuccini (1645-1649)

Hard pressed by the army of the Parliament and their Scottish allies in the English civil war, King Charles I concludes a truce with the Catholic insurgents in Ireland in the hope of persuading them to organize a force to come to his assistance against his rebels at home. Pope Innocent X, seeing in this situation the possibility of a revival of Church influence in Ireland, despatches Archbishop Giovanni Battista Rinuccini as Apostolic Nuncio to the government of the Catholic Confederation at Kilkenny, with instructions «to restore and re-establish the public exercise of the Catholic religion in the island of Ireland ». But neither the king nor his Irish deputy, the Earl of Ormond, have any intention of making such a concession to the Catholics, who in any case are divided and demoralised by their irreconcilable sectional interests. Hence the impossible mission of the Nuncio, Archbishop Rinuccini, and another chapter in the tragic story of Ireland, which then lies prostrate before the fury of Cromwell.Rudement éprouvé par l'armée du Parlement et les troupes écossaises, le roi Charles 1er négocie une trêve avec les rebelles catholiques d'Irlande dans l'espoir de les rallier à sa cause. Supputant un rétablissement possible de l'influence de l'Eglise en Irlande, le Pape Innocent X envoie l'archevêque Jean-Baptiste Rinuccini comme Nonce Apostolique auprès du gouvernement de la Confédération Catholique siégeant à Kilkenny, avec pour mission «de restaurer et de rétablir l'exercice public de la religion catholique dans l'île de l'Irlande». Mais ni le Roi ni son représentant en Irlande, le Comte d'Ormond, n'ont la moindre intention d'accorder une telle concession aux catholiques qui sont minés par d'implacables dissensions internes et querelles de personnes. D'où l'échec prévisible de la mission du Nonce Rinuccini dans cette Irlande déchirée et bientôt abandonnée à la fureur de Cromwell.O'Sullivan Tadhg F. The Impossible Diplomatic Mission of Battista Rinuccini (1645-1649). In: Études irlandaises, n°18-2, 1993. pp. 87-92

Joseph Morrison Skelly with a foreword by President Mary Robinson : Irish Diplomacy at the United Nations, 1945-1965

O'Sullivan Tadhg F. Joseph Morrison Skelly with a foreword by President Mary Robinson : Irish Diplomacy at the United Nations, 1945-1965. In: Études irlandaises, n°23-1, 1998. pp. 237-238