PerfVis: Pervasive Visualization in Immersive AugmentedReality for Performance Awareness

Developers are usually unaware of the impact of code changes to the performance of software systems. Although developers can analyze the performance of a system by executing, for instance, a performance test to compare the performance of two consecutive versions of the system, changing from a programming task to a testing task would disrupt the development flow. In this paper, we propose the use of a city visualization that dynamically provides developers with a pervasive view of the continuous performance of a system. We use an immersive augmented reality device (Microsoft HoloLens) to display our visualization and extend the integrated development environment on a computer screen to use the physical space. We report on technical details of the design and implementation of our visualization tool, and discuss early feedback that we collected of its usability. Our investigation explores a new visual metaphor to support the exploration and analysis of possibly very large and multidimensional performance data. Our initial result indicates that the city metaphor can be adequate to analyze dynamic performance data on a large and non-trivial software system.Comment: ICPE'19 vision, 4 pages, 2 figure, conferenc

Flying PIV measurements in a 4-valve IC engine water analogue to characterize the near-wall flow evolution

For a deeper understanding of the highly unsteady near-wall boundary layer flows in internal combustion (IC) engines, PIV-based flow field measurements close to the inner cylinder and piston walls within transparent engines are required. The herein described flying PIV method in combination with a scanning light-sheet provides time-resolved PIV measurements in a transparent IC engine water analogue in a radial plane 1.5 mm apart from the planar piston crown while the piston is moving. The light-sheet is parallel to the piston surface and moves with the piston thanks to the scanning technique that synchronizes the sheet motion with the non-linear piston motion. A compact high speed camera is positioned within the piston shaft below the transparent piston head and records the particle fields within the illuminated plane in time-resolved manner. The measurements are realized in a water-analogue of a 4-valve engine at 950 rpm engine speed in real situation. Instantaneous pictures are compared to phase-averaged velocity maps and allowed to localize regions of high cycle-to-cycle fluctuations

Site-specific DNA substrates for human excision repair: comparison between deoxyribose and base adducts

AbstractBackground: The genetic integrity of living organisms is maintained by a complex network of DNA repair pathways. Nucleotide excision repair (NER) is a versatile process that excises bulky base modifications from DNA. To study the substrate range of this system, we constructed bulky deoxyribose adducts that do not affect the chemistry of the corresponding bases. These novel adducts were incorporated into double-stranded DNA in a site-specific manner and the repair of the modified sites was investigated.Results: Using restriction enzymes as a probe for DNA modification, we confirmed that the resulting substrates contained the bulky deoxyribose adducts at the expected position. DNA containing these unique adducts did not stimulate DNA repair synthesis when mixed with an NER-competent human cell extract. Inefficient repair of deoxyribose adducts was confirmed by monitoring the release of single-stranded oligonucleotides during the excision reaction that precedes DNA repair synthesis. As a control, the same human cell extract was able to process a base adduct of comparable size.Conclusions: Our results indicate that modification of DNA bases rather than disruption of the sugar-phosphate backbone is an important determinant for damage recognition by the human NER system. Specific positions in DNA may thus be modified without eliciting NER responses. This observation suggests new strategies for anticancer drug design to generate DNA modifications that are refractory to repair processes

Scanning Near-Field Optical Coherent Spectroscopy of Single Molecules at 1.4 Kelvin

We present scanning near-field extinction spectra of single molecules embedded in a solid matrix. By varying the molecule-tip separation, we modify the line shape of the spectra, demonstrating the coherent nature of the interaction between the incident laser light and the excited state of the molecule. We compare the measured data with the outcome of numerical calculations and find a very good agreement.Comment: 3 pages, 5 figures, submitted to Optics Letter

Does the β-Blocker Nebivolol Increase Coronary Flow Reserve?

Introduction: Nebivolol, a highly selective β1-adrenergic receptor-blocker, increases basal and stimulated endothelial nitric oxide (NO)-release. It is unknown, whether coronary perfusion is improved by the increase in NO availability. Therefore, we sought to evaluate the effect of nebivolol on coronary flow reserve (CFR) and collateral flow. Methods: Doppler-flow wire derived coronary flow velocity measurements were obtained in ten controls and eight patients with coronary artery disease (CAD) at rest and after intracoronary nebivolol. CFR was defined as maximal flow during adenosine-induced hyperemia divided by resting flow. In the CAD group, collateral flow was determined after dilatation of a flow-limiting coronary stenosis. Collateral flow index (CFI) was defined as the ratio of flow velocity during balloon inflation divided by resting flow. Results: CFR at rest was 3.0 ± 0.6 in controls and 2.1 ± 0.4 in CAD patients. After intracoronary doses of 0.1, 0.25, and 0.5mg nebivolol, CFR increased to 3.4 ± 0.7, 3.9 ± 0.9, and 4.0 ± 0.1 (p < 0.01) in controls, and to 2.3 ± 0.7, 2.6 ± 0.9, and 2.6 ± 0.5 (p < 0.05) in CAD patients. CFI decreased significantly with intracoronary nebivolol and correlated to changes in heart rate (r = 0.75, p < 0.001) and rate-pressure product (r = 0.59, p = 0.001). Discussion: Intracoronary nebivolol is associated with a significant increase in CFR due to reduction in resting flow (controls), or due to an increase in maximal coronary flow (CAD patients). CFI decreased with nebivolol parallel to the reduction in myocardial oxygen consumptio

Stent thrombosis following bare-metal stent implantation: success of emergency percutaneous coronary intervention and predictors of adverse outcome

Aims To investigate the efficacy and outcome of emergency percutaneous coronary interventions (PCI) in patients with stent thrombosis. Methods and results Between 1995 and 2003, 6058 patients underwent bare-metal stent implantation, of which 95 (1.6%) patients suffered from stent thrombosis. The timing of stent thrombosis was acute in 10 (11%), subacute in 61 (64%), and late in 24 (25%) patients. Procedural and clinical outcomes of emergency PCI for treatment of stent thrombosis were investigated. Emergency PCI was successful in 86 (91%), complicated by death in 2 (2%), and coronary artery bypass grafting in 2 (2%) patients. Myocardial infarction occurred in 77 (81%) patients with a peak creatine kinase level of 1466±1570 U/L. Left ventricular ejection fraction declined from 0.54±0.19 prior to 0.48±0.16 (P<0.05) at the time of stent thrombosis after emergency PCI. A 6 month major adverse clinical events comprised death (11%), reinfarction (16%), and recurrent stent thrombosis (12%) after emergency PCI. Multivariable logistic regression analysis identified the achievement of TIMI 3 flow (OR=0.1, CI 95% 0.01-0.54, P<0.001) and diameter stenosis <50% (OR=0.06, CI 95% 0.01-0.32, P<0.001) during emergency PCI to be independently associated with a reduced risk of cardiac death. Recurrent stent thrombosis was independently predicted by the omission of abciximab (OR=4.3, CI 95% 1.1-17.5). Conclusion Emergency PCI for treatment of stent thrombosis effectively restores vessel patency and flow. Patients presenting with stent thrombosis are at risk for recurrent myocardial infarction and recurrent stent thrombosi

Benefit from decline: the primary transcriptome of Alteromonas macleodii str. Te101 during Trichodesmium demise

Interactions between co-existing microorganisms deeply affect the physiology of the involved organisms and, ultimately, the function of the ecosystem as a whole. Copiotrophic Alteromonas are marine gammaproteobacteria that thrive during the late stages of phytoplankton blooms in the marine environment and in laboratory co-cultures with cyanobacteria such as Trichodesmium. The response of this heterotroph to the sometimes rapid and transient changes in nutrient supply when the phototroph crashes is not well understood. Here, we isolated and sequenced the strain Alteromonas macleodii str. Te101 from a laboratory culture of Trichodesmium erythraeum IMS101, yielding a chromosome of 4.63 Mb and a single plasmid of 237 kb. Increasing salinities to ≥43 ppt inhibited the growth of Trichodesmium but stimulated growth of the associated Alteromonas. We characterized the transcriptomic responses of both microorganisms and identified the complement of active transcriptional start sites in Alteromonas at single-nucleotide resolution. In replicate cultures, a similar set of genes became activated in Alteromonas when growth rates of Trichodesmium declined and mortality was high. The parallel activation of fliA, rpoS and of flagellar assembly and growth-related genes indicated that Alteromonas might have increased cell motility, growth, and multiple biosynthetic activities. Genes with the highest expression in the data set were three small RNAs (Aln1a-c) that were identified as analogs of the small RNAs CsrB-C in E. coli or RsmX-Z in pathogenic bacteria. Together with the carbon storage protein A (CsrA) homolog Te101_05290, these RNAs likely control the expression of numerous genes in responding to changes in the environmentThis work was supported by the EU project MaCuMBA (grant agreement no. 311975) to WRH and FRVby the German Israeli Foundation grant no. 1133 to IB-F and WRHSupport of ML-P by a postdoctoral fellowship from the Valencian Consellería de Educació, Investigació, Cultura i Esport (APOSTD/2016/051)of SH by the China Scholarship Council is gratefully acknowledged