Progress and Poverty—1965 Version

The first hard X-ray laser, the Linac Coherent Light Source (LCLS), produces 120 shots per second. Particles injected into the X-ray beam are hit randomly and in unknown orientations by the extremely intense X-ray pulses, where the femtosecond-duration X-ray pulses diffract from the sample before the particle structure is significantly changed even though the sample is ultimately destroyed by the deposited X-ray energy. Single particle X-ray diffraction experiments generate data at the FEL repetition rate, resulting in more than 400,000 detector readouts in an hour, the data stream during an experiment contains blank frames mixed with hits on single particles, clusters and contaminants. The diffraction signal is generally weak and it is superimposed on a low but continually fluctuating background signal, originating from photon noise in the beam line and electronic noise from the detector. Meanwhile, explosion of the sample creates fragments with a characteristic signature. Here, we describe methods based on rapid image analysis combined with ion Time-of-Flight (ToF) spectroscopy of the fragments to achieve an efficient, automated and unsupervised sorting of diffraction data. The studies described here form a basis for the development of real-time frame rejection methods, e. g. for the European XFEL, which is expected to produce 100 million pulses per hour. (C)2014 Optical Society of Americ

Coherent diffraction of single Rice Dwarf virus particles using hard X-rays at the Linac Coherent Light Source

Single particle diffractive imaging data from Rice Dwarf Virus (RDV) were recorded using the Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source (LCLS). RDV was chosen as it is a wellcharacterized model system, useful for proof-of-principle experiments, system optimization and algorithm development. RDV, an icosahedral virus of about 70 nm in diameter, was aerosolized and injected into the approximately 0.1 mu m diameter focused hard X-ray beam at the CXI instrument of LCLS. Diffraction patterns from RDV with signal to 5.9 angstrom ngstrom were recorded. The diffraction data are available through the Coherent X-ray Imaging Data Bank (CXIDB) as a resource for algorithm development, the contents of which are described here.11Ysciescopu

Towards introspective loop closure in 4D radar SLAM

Imaging radar is an emerging sensor modality in the context of Localization and Mapping (SLAM), especially suitable for vision-obstructed environments. This article investigates the use of 4D imaging radars for SLAM and analyzes the challenges in robust loop closure. Previous work indicates that 4D radars, together with inertial measurements, offer ample information for accurate odometry estimation. However, the low field of view, limited resolution, and sparse and noisy measurements render loop closure a significantly more challenging problem. Our work builds on the previous work - TBV SLAM - which was proposed for robust loop closure with 360$^\circ$ spinning radars. This article highlights and addresses challenges inherited from a directional 4D radar, such as sparsity, noise, and reduced field of view, and discusses why the common definition of a loop closure is unsuitable. By combining multiple quality measures for accurate loop closure detection adapted to 4D radar data, significant results in trajectory estimation are achieved; the absolute trajectory error is as low as 0.46 m over a distance of 1.8 km, with consistent operation over multiple environments.Comment: Submitted to the workshop "Radar in Robotics: Resilience from Signal to Navigation" at ICRA 202

Lidar-level localization with radar? The CFEAR approach to accurate, fast and robust large-scale radar odometry in diverse environments

This paper presents an accurate, highly efficient, and learning-free method for large-scale odometry estimation using spinning radar, empirically found to generalize well across very diverse environments -- outdoors, from urban to woodland, and indoors in warehouses and mines - without changing parameters. Our method integrates motion compensation within a sweep with one-to-many scan registration that minimizes distances between nearby oriented surface points and mitigates outliers with a robust loss function. Extending our previous approach CFEAR, we present an in-depth investigation on a wider range of data sets, quantifying the importance of filtering, resolution, registration cost and loss functions, keyframe history, and motion compensation. We present a new solving strategy and configuration that overcomes previous issues with sparsity and bias, and improves our state-of-the-art by 38%, thus, surprisingly, outperforming radar SLAM and approaching lidar SLAM. The most accurate configuration achieves 1.09% error at 5Hz on the Oxford benchmark, and the fastest achieves 1.79% error at 160Hz.Comment: Accepted for publication in Transactions on Robotics. Edited 2022-11-07: Updated affiliation and citatio

Optimering av bemanning för att möta kundflöde och öka servicen – En jämförande fallstudie på Stadium Helsingborg

Problembeskrivning: I retailbranschen, som är en personalintensiv bransch, ställs det allt högre krav på servicen i butiken. Om företaget kan förmedla en upplevelse av hög kvalitet genom bra service skapas lojala och nöjda kunder. Dålig optimering av personal i butiken kan vara kostsamt och ge upphov till dålig service. Syfte och Frågeställningar: Syftet med uppsatsen är att belysa vikten av att arbeta med service och koppla detta till optimering av bemanning i butik. Frågeställningarna blir följande: • Hur arbetar butiker effektivt med bemanning? • Hur leder optimerad butiksbemanning till bättre service mot kunderna? Presentation av fallföretaget: Arbetet är ett resultat av en fallstudie av Stadiumbutikerna på Väla och Kullagatan i Helsingborg. Avgränsningar: Vi har avgränsat oss till att endast studera ett företag i en stad. Vi har inte belyst skillnaden av lokaliseringen på de två butikerna. Enkäten är avgränsad och representerar bara en ögonblicksbild av verksamheten och dess förutsättningar. Metod: I arbetet har vi använt oss av en kombination av kvantitativa enkäter och kvalitativa intervjuer. Dessa har vi applicerat på Stadium Helsingborg som en jämförande fallstudie. Teoretisk ram: Tyngden i den teoretiska ramen ligger på servicemanagement forskning av Grönroos med SERVQUAL och gapanalys med stöd från Normann med serviceföretagens tre goda cirklar. Tidigare forskning: I avsnittet har vi diskuterat orden kundflöde, service och bemanning för butiken. Resultat: Kundnöjdhetsundersökningen resulterade i att kunden tycker servicen spelar en avgörande roll i valet av butik. Vi har även identifierat en grupp med kritiska kunder som vi anser man borde arbeta med. Stadium arbetar aktivt med att hantera kundflödet genom deras personalbemanning för att upprätthålla en hög servicegrad mot kunden. Analys: Stadium har minimala servicegap mellan kundens och ledningens uppfattning, vilket tyder på att Stadium är medvetna om deras servicekvalitet. Stadium hanterar De tre goda cirklarna, vilka är, sanningens ögonblick, makrocirkeln och den interna servicecirkeln, på ett effektivt och kundvänligt sätt. Slutsatser & diskussion: Att möta kundens behov är viktigt. Det är därför viktigt att tänka på servicen i butiken och att servicen kan användas som en stark konkurrensfördel. Om man brister på någon faktor i butiken påverkas kundens helhetsintryck och kundens vistelse i butiken kan bli negativ. Det är därför viktigt att arbeta med samtliga aspekter såsom service, kundflöde samt optimeringen av personal i butiken

Slime Attack! A forced collaboration game across four iPads designed for children in primary school

The increased usage of tablets in recent years has caused significant changes throughout society. This change can also be seen in schools where tablets are now incorporated throughout primary education. Though, tablets are often used individually causing a lack of collaboration, which is an essential part of education. This paper describes the development process of the mobile game Slime Attack! and how it encourages young children aged 7-9 to cooperate while playing. Slime Attack! is a castle defence game, played on four iPads placed adjacent to each other, collectively forming a large playing field. Initially, a prestudy was carried through, mainly focusing on interaction design theory. Another important basis came from interviews concluded with the intended user group. The gained knowledge from the prestudy provided a foundation for the development to further build upon. This foundation, summarized in a number of strict requirements, together with the narrow scope of the project were thereafter used to form the final game concept. Slime Attack! was shown to encourage collaboration amongst children by fueling a discussion of strategies concerning the expansion of their outpost, and also in supporting each other when the amount of enemies increased. We also discuss flaws in the prototype, including the children’s initial competitive playing style, and issues with the user interface that slowed down the onset of collaboration. Finally, we put forth a number of possible changes to the game that would address the major flaws we found in our tests

A data set from flash X-ray imaging of carboxysomes

Citation: Hantke, M. F., Hasse, D., Ekeberg, T., John, K., Svenda, M., Loh, D., . . . Maia, F. R. N. C. (2016). A data set from flash X-ray imaging of carboxysomes. Scientific Data, 3. doi:10.1038/sdata.2016.61Ultra-intense femtosecond X-ray pulses from X-ray lasers permit structural studies on single particles and biomolecules without crystals. We present a large data set on inherently heterogeneous, polyhedral carboxysome particles. Carboxysomes are cell organelles that vary in size and facilitate up to 40% of Earth's carbon fixation by cyanobacteria and certain proteobacteria. Variation in size hinders crystallization. Carboxysomes appear icosahedral in the electron microscope. A protein shell encapsulates a large number of Rubisco molecules in paracrystalline arrays inside the organelle. We used carboxysomes with a mean diameter of 115±26 nm from Halothiobacillus neapolitanus. A new aerosol sample-injector allowed us to record 70,000 low-noise diffraction patterns in 12 min. Every diffraction pattern is a unique structure measurement and high-throughput imaging allows sampling the space of structural variability. The different structures can be separated and phased directly from the diffraction data and open a way for accurate, high-throughput studies on structures and structural heterogeneity in biology and elsewhere

Linking crop traits to transcriptome differences in a progeny population of tetraploid potato

Background Potato is the third most consumed crop in the world. Breeding for traits such as yield, product quality and pathogen resistance are main priorities. Identifying molecular signatures of these and other important traits is important in future breeding efforts. In this study, a progeny population from a cross between a breeding line, SW93-1015, and a cultivar, Desiree, was studied by trait analysis and RNA-seq in order to develop understanding of segregating traits at the molecular level and identify transcripts with expressional correlation to these traits. Transcript markers with predictive value for field performance applicable under controlled environments would be of great value for plant breeding. Results A total of 34 progeny lines from SW93-1015 and Desiree were phenotyped for 17 different traits in a field in Nordic climate conditions and controlled climate settings. A master transcriptome was constructed with all 34 progeny lines and the parents through a de novo assembly of RNA-seq reads. Gene expression data obtained in a controlled environment from the 34 lines was correlated to traits by different similarity indices, including Pearson and Spearman, as well as DUO, which calculates the co-occurrence between high and low values for gene expression and trait. Our study linked transcripts to traits such as yield, growth rate, high laying tubers, late and tuber blight, tuber greening and early flowering. We found several transcripts associated to late blight resistance and transcripts encoding receptors were associated to Dickeya solani susceptibility. Transcript levels of a UBX-domain protein was negatively associated to yield and a GLABRA2 expression modulator was negatively associated to growth rate. Conclusion In our study, we identify 100's of transcripts, putatively linked based on expression with 17 traits of potato, representing both well-known and novel associations. This approach can be used to link the transcriptome to traits. We explore the possibility of associating the level of transcript expression from controlled, optimal environments to traits in a progeny population with different methods introducing the application of DUO for the first time on transcriptome data. We verify the expression pattern for five of the putative transcript markers in another progeny population

Use of Singing for Lung Health as an alternative training modality within pulmonary rehabilitation for COPD:a randomised controlled trial

BACKGROUND: Pulmonary rehabilitation (PR) is a cornerstone in chronic obstructive pulmonary disease (COPD) management. However, PR adherence is generally low, and barriers include availability, economic issues, motivation and an inability to attend or perform physical training. Therefore, alternative, evidence-based PR activities are required. Singing may have benefits for quality of life (QoL), respiratory control and well-being in COPD, but the impact on the PR key outcome, physical exercise capacity, is uncertain.METHODS: In this randomised controlled trial (NCT03280355), we investigated the effectiveness of 10 weeks of PR, including either "Singing for Lung Health" (SLH) training or standard physical exercise training (PExT). The primary outcome was a change in exercise capacity (6-min walk distance (6MWD)) from baseline to post-PR. Secondary outcomes were changes in QoL (St George's Respiratory Questionnaire (SGRQ)), Hospital Anxiety and Depression Score (HADS), lung function, dyspnoea and adherence.RESULTS: We included 270 COPD patients, and 195 completed the study. Demographics across groups were comparable, and both groups improved significantly in 6MWD and SGRQ score. SLH was non-inferior to PExT in improving 6MWD (mean±sd 13.1±36.3 m versus 14.1±32.3 m, p=0.81; difference 1.0 m, 95% CI -7.3-9.3 m) with 21.8% and 25.0%, respectively (p=0.57), reaching the 6MWD minimal important difference of 30 m. We found no significant between-group differences concerning SGRQ, HADS, lung function, dyspnoea or adherence. CONCLUSION: Our study suggests that SLH is non-inferior to PExT in improving 6MWD during a 10-week PR programme. Future studies addressing reproducibility, long-term effects and health economics are needed.</p

Single-shot diffraction data from the Mimivirus particle using an X-ray free-electron laser

Citation: Ekeberg, T., Svenda, M., Seibert, M. M., Abergel, C., Maia, F. R. N. C., Seltzer, V., . . . Hajdu, J. (2016). Single-shot diffraction data from the Mimivirus particle using an X-ray free-electron laser. Scientific Data, 3. doi:10.1038/sdata.2016.60Free-electron lasers (FEL) hold the potential to revolutionize structural biology by producing X-ray pules short enough to outrun radiation damage, thus allowing imaging of biological samples without the limitation from radiation damage. Thus, a major part of the scientific case for the first FELs was three-dimensional (3D) reconstruction of non-crystalline biological objects. In a recent publication we demonstrated the first 3D reconstruction of a biological object from an X-ray FEL using this technique. The sample was the giant Mimivirus, which is one of the largest known viruses with a diameter of 450 nm. Here we present the dataset used for this successful reconstruction. Data-analysis methods for single-particle imaging at FELs are undergoing heavy development but data collection relies on very limited time available through a highly competitive proposal process. This dataset provides experimental data to the entire community and could boost algorithm development and provide a benchmark dataset for new algorithms