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Cranio-caudal respiratory motion and liver activity cause a variety of complex myocardial perfusion (MP) artifacts, especially in the inferior myocardial wall, that may also mask cardiac defects. To assess and characterise such artifacts, an anthropomorphic thorax with moving thoracic phantoms can be utilised in SPECT MP imaging. In this study, a liver phantom was developed and anatomically added into an anthropomorphic phantom that also encloses an ECG beating cardiac phantom and breathing lungs’ phantom. A cranio-caudal respiratory motion was also developed for the liver phantom and it was synchronised with the corresponding ones of the other thoracic phantoms. This continuous motion was further divided into isochronous dynamic respiratory phases, from end-exhalation to end-inspiration, to perform SPECT acquisitions in different respiratory phases. The new motions’ parameters and settings were measured by mechanical means and also validated in a clinical environment by acquiring CT images and by using two imaging software packages. To demonstrate the new imaging capabilities of the phantom assembly, SPECT/CT MP acquisitions were performed and compared to previous phantom and patients studies. All thoracic phantoms can precisely perform physiological motions within the anthropomorphic thorax. The new capabilities of the phantom assembly allow to perform SPECT/CT MP acquisitions for different cardiac-liver activity ratios and cardiac-liver proximities in supine and, for first time, in prone position. Thus, MP artifacts can be characterised and motion correction can be performed due to these new capabilities. The impact of artifacts and motion correction on defect detection can be also investigated.

We present an analysis of proton-number fluctuations in sNN=2.4 GeV Au197+Au197 collisions measured with the High-Acceptance DiElectron Spectrometer (HADES) at GSI Helmholtzzentrum fur Schwerionenforschung, Darmstadt. With the help of extensive detector simulations done with Isospin Quantum Molecular Dynamics (IQMD) transport model events including nuclear clusters, various nuisance effects influencing the observed proton cumulants have been investigated. Acceptance and efficiency corrections have been applied as a function of fine-grained rapidity and transverse momentum bins, as well as considering local track density dependencies. Next, the effects of volume changes within particular centrality selections have been considered and beyond-leading-order corrections have been applied to the data. The efficiency and volume-corrected proton number moments and cumulants Kn of orders n=1, 2, 3, and 4 have been obtained as a function of centrality and phase-space bin, as well as the corresponding correlators Cn. We find that the observed correlators show a power-law scaling with the mean number of protons, i.e., Cn∞«N»n, indicative of mostly long-range multiparticle correlations in momentum space. We also present a comparison of our results with Au + Au collision data obtained at the Relativistic Heavy Ion Collider (RHIC) at similar centralities but higher √sNN.

Pion induced reactions provide unique opportunities for an unambiguous description of baryonic resonances and their coupling channels by means of a partial wave analysis. Using the secondary pion beam at SIS18, the two pion production in the second resonance region has been investigated to unravel the role of the $N(1520) \frac{3}{2}^-$ resonance in the intermediate $\rho$ production. Results on exclusive channels with one pion ($\pi^{-}p$) and two pions ($\pi^{+}\pi^{-}n$, $\pi^{0}\pi^{-}p$) in the final state measured in the $\pi^{-}-p$ reaction at four different pion beam momenta (0.650, 0.685, 0.733, and 0.786 GeV/c) are presented. The excitation function of the different partial waves and $\Delta\pi$, $N\sigma$ and $N\rho$ isobar configurations is obtained, using the Bonn-Gatchina partial wave analysis. The $N(1520) \frac{3}{2}^-$ resonance is found to dominate the $N\rho$ final state with the branching ratio $BR=12.2 \pm 1.9\%$.

The aim of this study was to develop controlled thoracic motions on a cardiac phantom and a breathing phantom, which both are inserted within an anthropomorphic thorax phantom. The cardiac phantom consists of a left ventricle and the breathing phantom of inflatable lungs. The diastole and systole of the left ventricle follows the Wigger diagram while the inflatable lungs follow a sinusoidal exponential pattern. An ECG can gate both the beating left ventricle and the SPECT imaging modality. In addition, the ECG beating left ventricle follows the inferior portion of the inflatable lungs in the cranio-caudal direction at the level of the diaphragm. The lungs and the left ventricle are able to simulate normal and deep breathing conditions. A Programmable Logic Controller precisely controls these motions in time intervals of 10 ms. All motions can be operated simultaneously or independently to each other. A number of motion limitations of other physical phantoms have been overcome. This phantom assembly with variable cardiac defects can be utilized to optimize myocardial perfusion imaging.

We present the first observation of K- and \phi absorption within nuclear matter by means of \pi- -induced reactions on C and W targets at an incident beam momentum of 1.7 GeV/c studied with HADES at SIS18/GSI. The double ratio (K-/K+)W / (K-/K+)C is found to be 0.319 \pm 0.009(stat)+0.014-0.012 (syst) indicating a larger absorption of K- in heavier targets as compared to lighter ones. The measured \phi/K- ratios in \pi-+C and \pi^- +W reactions within the HADES acceptance are found to be equal to $0.55 \pm 0.03(stat)+0.06-0.07$ (syst) and to $0.63 \pm 0.05(stat)-0.11+0.11$ (syst), respectively. The similar ratios measured in the two different reactions demonstrate for the first time experimentally that the dynamics of the \phi meson in nuclear medium is strongly coupled to the K- dynamics. The large difference in the \phi production off C and W nuclei is discussed in terms of a strong \phiN in-medium coupling., Comment: 6 pages, 3 figures

International audience; About 10 μs after the Big Bang, the universe was filled—in addition to photons and leptons—with strong-interaction matter consisting of quarks and gluons, which transitioned to hadrons at temperatures close to kT = 150 MeV and densities several times higher than those found in nuclei. This quantum chromodynamics (QCD) matter can be created in the laboratory as a transient state by colliding heavy ions at relativistic energies. The different phases in which QCD matter may exist depend for example on temperature, pressure or baryochemical potential, and can be probed by studying the emission of electromagnetic radiation. Electron–positron pairs emerge from the decay of virtual photons, which immediately decouple from the strong interaction, and thus provide information about the properties of QCD matter at various stages. Here, we report the observation of virtual photon emission from baryon-rich QCD matter. The spectral distribution of the electron–positron pairs is nearly exponential, providing evidence for a source of temperature in excess of 70 MeV with constituents whose properties have been modified, thus reflecting peculiarities of strong-interaction QCD matter. Its bulk properties are similar to the dense matter formed in the final state of a neutron star merger, as apparent from recent multimessenger observation.

Red Blood Cells (RBCs) samples from healthy volunteers, β-thalassaemia major and β-thalassaemia intermedia patients were studied by means of 57Fe Mossbauer Spectroscopy (MS). The MS spectra from the RBCs of the thalassaemia patients showed the existence of significant amounts of ferritin-like iron, and in particular in the 82% of the β-thalassaemia intermedia ones. Also, β-thalassaemia intermedia patients were found to have higher Liver Iron Concentration (LIC) when compared to the β-thalassaemia major patients, as assessed by MRI exams, even though they had on an average about half the serum ferritin levels.

The hearts, kidneys, livers, spleens and brains of 57Fe enriched wild-type and heterozygous β-thalassaemic mice at 1, 3, 6 and 9 months of age were studied by means of Mossbauer Spectroscopy at 80 K. Ferritin-like iron depositions in the heart and the brain of the thalassaemic mice were found to be slightly increased while significant amounts of Ferritin-like iron were found in the kidneys, liver and spleen. The Ferritin-like iron doublet, found in the organs, could be further separated into two sub-doublets representing the inner and surface structures of ferritin’s mineral core. Surface iron sites were found to be predominant in the hearts and brains of all mice and in the kidneys of the wild-type animals. Ferritin rich in inner iron sites was predominant in the kidneys of the thalassaemic mice, as well as in the livers and in the spleens. The inner-to-surface iron sites ratio was elevated in all thalassaemic samples indicating that besides ferritin amount, the disease can also affect ferritin’s mineral core structure.

We report on the investigation of Δ(1232) production and decay in proton-proton collisions at a kinetic energy of 1.25 GeV measured with HADES. Exclusive dilepton decay channels ppe+e− and ppe+e−γ have been studied and compared with the partial-wave analysis of the hadronic ppπ0 channel. They allow to access both Δ+→pπ0(e+e−γ) and Δ+→pe+e− Dalitz decay channels. The perfect reconstruction of the well-known π0 Dalitz decay serves as a proof of the consistency of the analysis. The Δ Dalitz decay is identified for the first time and the sensitivity to N-Δ transition form factors is tested. The Δ(1232) Dalitz decay branching ratio is also determined for the first time; our result is (4.19 ± 0.62 syst. ± 0.34 stat.) ×10−5, albeit with some model dependence.

Physical phantoms are useful to optimize MPI. Previously, phantoms of beating left ventricles were used with or without phantoms of static lungs to investigate MPI. Both cardiac and respiratory motions contribute to the degradation of image quality and may decrease the diagnostic accuracy. The different frequencies of these motions constitute an inevitable problem for all imaging modalities. The aim of this work was to construct human-sized inflatable lungs with lung-equivalent density by injection molding. The tidal volume and the breathing cycle of the inflatable lungs were mechanically validated. SPECT/CT acquisitions and the OsiriX imaging software were also used to validate the tidal volume of the lungs. Respiratory motion can be simulated in MPI using these inflatable lungs.

BACKGROUND: The aim of this study was to determine the impact of respiratory motion correction on SPECT MPI and on defect detection using a phantom assembly.METHODS: SPECT/CT data were acquired using an anthropomorphic phantom with inflatable lungs and with an ECG beating and moving cardiac compartment. The heart motion followed the respiratory pattern in the cranio-caudal direction to simulate normal or deep breathing. Small or large transmural defects were inserted into the myocardial wall of the left ventricle. SPECT/CT images were acquired for each of the four respiratory phases, from exhale to inhale. A respiratory motion correction was applied using an image-based method with transformation parameters derived from the SPECT data by a non-rigid registration algorithm. A report on defect detection from two physicians and a quantitative analysis on MPI data were performed before and after applying motion correction.RESULTS: Respiratory motion correction eliminated artifacts present in the images, resulting in a uniform uptake and reduction of motion blurring, especially in the inferior and anterior regions of the LV myocardial walls. The physicians' report after motion correction showed that images were corrected for motion.CONCLUSIONS: A combination of motion correction with attenuation correction reduces artifacts in SPECT MPI. AC-SPECT images with and without motion correction should be simultaneously inspected to report on small defects.

We present an analysis of the hyperons Λ(1405) and Σ(1385) + for p+p reactions at 3.5 GeV kinetic beam energy. The data were taken with the High Acceptance Di-Electron Spectrometer (HADES). A Λ(1405) signal could be reconstructed in both charged decay channels Λ(1405)→Σ± π ∓ . The obtained statistics of the Σ(1385) + signal allows also differential studies.

We present results on the K∗(892)+ production in proton-proton collisions at a beam energy of E=3.5 GeV, which is hitherto the lowest energy at which this mesonic resonance has been observed in nucleon-nucleon reactions. The data are interpreted within a two-channel model that includes the three-body production of K∗(892)+ associated with the Λ or Σ hyperon. The relative contributions of both channels are estimated. Besides the total cross section σ(p+p→K∗(892)++X)=9.5±0.9-0.9+1.1±0.7μb, which adds a new data point to the excitation function of the K∗(892)+ production in the region of low excess energy, transverse momenta and angular spectra are extracted and compared with the predictions of the two-channel model. The spin characteristics of K∗(892)+ are discussed as well in terms of the spin-alignment.

This study aims to investigate the impact of respiratory motion correction on the diagnostic accuracy in myocardial perfusion SPECT. SPECT/CT data were acquired using an anthropomorphic phantom. The lungs were given an exponential sine-wave respiratory pattern resulting in heart motion of 1.5cm and 2.7cm in the cranio-caudal direction at the level of the diaphragm for the simulation of normal and deep breathing respectively. Defects were inserted into the myocardial wall. Motion correction was applied using an image based method with transformation parameters derived by a non-rigid registration algorithm. Images were evaluated by nuclear medicine physician. Respiratory motion correction eliminated artifactual defects present in the images, resulting in uniform uptake and reduction of motion blurring especially in the inferior and anterior walls. Increased defect contrast and thinner appearance of the heart wall were observed. The extent of improvement depended on the amplitude of the motion displacement; Although the impact of motion correction on the detection task was not as apparent for 1.5cm as with 2.7cm motion, in both cases correction recovered the correct defect size and contrast while rectifying the artifactual decrease of uptake. Finally, a combination of motion correction with attenuation correction enhanced these findings. Respiratory motion correction reduces motion artefacts in SPECT images resulting in improved defect detectability in myocardial perfusion imaging.

An exclusive analysis of the four-body final states Λ+p+π++K0 and Σ0+p+π++K0 measured with HADES for p+p collisions at a beam kinetic energy of 3.5 GeV is presented. The analysis uses various phase space variables, such as missing mass and invariant mass distributions, in the four-particle event selection (p,π+,π+,π-) to find cross sections of the different production channels, contributions of the intermediate resonances Δ++ and Σ(1385)+, and corresponding angular distributions. A dominant resonant production is seen, where the reaction Λ+Δ+++K0 has a cross section about ten times higher (29.45±0.08-1.46+1.67±2.06μb) than the analogous nonresonant reaction (2.57±0.02-1.98+0.21±0.18μb). A similar result is obtained in the corresponding Σ0 channels with 9.26±0.05-0.31+1.41±0.65μb in the resonant and 1.35±0.02-1.35+0.10±0.09μb in the nonresonant reactions. © 2014 American Physical Society.

Data on inclusive pion and $\ensuremath{\eta}$ production measured with the dielectron spectrometer HADES in the reaction $p+{}^{93}\mathrm{Nb}$ at a kinetic beam energy of 3.5 GeV are presented. Our results, obtained with the photon-conversion method, supplement the rather sparse information on neutral-meson production in proton-nucleus reactions existing for this bombarding energy regime. The reconstructed ${e}^{+}{e}^{\ensuremath{-}}{e}^{+}{e}^{\ensuremath{-}}$ transverse-momentum and rapidity distributions are confronted with transport-model calculations, which account fairly well for both ${\ensuremath{\pi}}^{0}$ and $\ensuremath{\eta}$ production.

New results on the differential cross section in deuteron-proton elastic scattering are obtained at the deuteron kinetic energy of 2.5 GeV with the HADES spectrometer. The angular range of 69°-125° in the center of mass system is covered. The obtained results are compared with the relativistic multiple scattering model calculation using the CD-Bonn deuteron wave function. The data at fixed scattering angles in the c.m. are in qualitative agreement with the constituent counting rules prediction.

The diagnostic sensitivity of various SPECT MPI procedures was assessed using a pumping cardiac phantom with variable defects inserted in the myocardial wall of the left ventricle. A diagnostic evaluation of 142 myocardial defects was performed. A diagnosis blinded to prior-known conditions was compared to the known defects severity (transmural, subendocardial) and defects position within the myocardial wall of the left ventricle (apical, anterior, inferior) for three body types (average male, large male, large female). Non-attenuation corrected, attenuation corrected and gated SPECT MPI were performed. The diagnostic sensitivity was improved when applying attenuation correction or gating techniques to identify subendocardial defects in the inferior, anterior and apical segments of the myocardial wall of the left ventricle for all three body types. Transmural defects could be identified without any attenuation correction or gating. The diagnostic sensitivity was improved when applying AC or GSPECT techniques.

We present results of an exclusive measurement of the first-excited state of the $\ensuremath{\Sigma}$ hyperon, $\ensuremath{\Sigma}{(1385)}^{+}$, produced in $p+p\ensuremath{\rightarrow}{\ensuremath{\Sigma}}^{+}+{K}^{+}+n$ at $3.5\phantom{\rule{0.28em}{0ex}}\mathrm{GeV}$ beam energy. The extracted data allow the detailed study of the invariant mass distribution of the $\ensuremath{\Sigma}{(1385)}^{+}$. The mass distribution is well described by a relativistic Breit-Wigner function with a maximum at ${m}_{0}=1383.2\ifmmode\pm\else\textpm\fi{}0.9\phantom{\rule{0.28em}{0ex}}\mathrm{MeV}/{c}^{2}$ and a width of $40.2\ifmmode\pm\else\textpm\fi{}2.1\phantom{\rule{0.28em}{0ex}}\mathrm{MeV}/{c}^{2}$. The exclusive production cross section comes out to be $22.27\ifmmode\pm\else\textpm\fi{}0.89\ifmmode\pm\else\textpm\fi{}1.{56}_{\ensuremath{-}2.10}^{+3.07}\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}b$. Angular distributions of the $\ensuremath{\Sigma}{(1385)}^{+}$ in different reference frames are found to be compatible with the hypothesis that $33%$ of $\ensuremath{\Sigma}{(1385)}^{+}$ result from the decay of an intermediate broad ${\ensuremath{\Delta}}^{++}$ excitation at about $2000\phantom{\rule{0.28em}{0ex}}\mathrm{MeV}/{c}^{2}$.

G. Agakishiev6, A. Balanda3, D. Belver16, A. Belyaev6, A. Blanco2, M. Bohmer9, J. L. Boyard14, P. Cabanelas16, E. Castro16, S. Chernenko6, J. Diaz17, A. Dybczak3, E. Epple8, L. Fabbietti8, O. Fateev6, P. Finocchiaro1, P. Fonte2,b, J. Friese9, I. Frohlich7, T. Galatyuk7,c, J. A. Garzon16, A. Gil17, M. Golubeva12, D. Gonzalez-Diazd , F. Guber12, M. Gumberidze14, T. Hennino14, R. Holzmann4, P. Huck9, A. Ierusalimov6, I. Iori11, f , A. Ivashkin12, M. Jurkovic9, B. Kampfer5,e, T. Karavicheva12, I. Koenig4, W. Koenig4, B. W. Kolb4, G. Korcyl3, G. Kornakov16, R. Kotte5, A. Kozuch3,g, A. Krasa15, F. Krizek15, R. Krucken9, H. Kuc3,14, W. Kuhn10, A. Kugler15, A. Kurepin12, A. Kurilkin6, P. Kurilkin6, P. Kahlitz5, V. Ladygin6, J. Lamas-Valverde16, S. Lang4, K. Lapidus8, T. Liu14, L. Lopes2, M. Lorenz7, L. Maier9, A. Mangiarotti2, J. Markert7, V. Metag10, B. Michalska3, J. Michel7, C. Muntz7, L. Naumann5, Y. C. Pachmayer7, M. Palka7, Y. Parpottas13, V. Pechenov4, O. Pechenova7, J. Pietraszko7, W. Przygoda3, B. Ramstein14, A. Reshetin12, J. Roskoss10, A. Rustamov4, A. Sadovsky12, P. Salabura3, A. Schmaha, J. Siebenson8, Yu.G. Sobolev15, S. Spataroh, H. Strobele7, J. Stroth7,4, C. Sturm4, A. Tarantola7, K. Teilab7, P. Tlusty15, M. Traxler4, R. Trebacz3, H. Tsertos13, T. Vasiliev6, V. Wagner15, M. Weber9, J. Wustenfeld5, S. Yurevich4, Y. Zanevsky6 (HADES collaboration)

Results on $\ensuremath{\Lambda}p$ femtoscopy are reported at the lowest energy so far. At a beam energy of $1.76A$ GeV, the reaction $\mathrm{Ar}+\mathrm{KCl}$ was studied with the High Acceptance Di-Electron Spectrometer (HADES) at SIS18/GSI. A high-statistics and high-purity $\ensuremath{\Lambda}$ sample was collected, allowing for the investigation of $\ensuremath{\Lambda}p$ correlations at low relative momenta. The experimental correlation function is compared to corresponding model calculations allowing the determination of the space-time extent of the $\ensuremath{\Lambda}p$ emission source. The $\ensuremath{\Lambda}p$ source radius is found to be slightly smaller than the $\mathit{pp}$ correlation radius for a similar collision system. The present $\ensuremath{\Lambda}p$ radius is significantly smaller than that found for $\mathrm{Au}+\mathrm{Au}/\mathrm{Pb}+\mathrm{Pb}$ collisions in the AGS, SPS, and RHIC energy domains but larger than that observed for electroproduction from He. Taking into account all available data, we find the $\ensuremath{\Lambda}p$ source radius to increase almost linearly with the number of participants to the power of one-third.

We gratefully acknowledge the useful discussions with H. Oeschler and K. Redlich. In particular we thank K. Redlich for providing the calculations by the statistical model. The HADES Collaboration gratefully acknowledges support from the following: BMBF Grants 06TM970I, 06GI146I, 06F-140, and 06DR135 (Germany); GSI (TMFR1, GI/ME3, OF/STR); Excellence Cluster of Universe (Germany); Grants GA AS CR IAA100480803 and MSMT LC 07050 (Czech Republic); Grant KBN 5P03B 140 20 (Poland); INFN (Italy); CNRS/IN2P3 (France);GrantsMCYT FPA2000-2041-C02-02 and XUGA PGID T02PXIC20605PN (Spain); Grant UCY-10.3.11.12 (Cyprus); INTAS Grant 06- 1000012-8861; and EU Contract RII3-CT-2004-506078.

Differentiating between various types of lesions in nuclear cardiology is a challenge. This work assesses the level of differentiation achievable between various low contrast lesions, as encountered in nuclear cardiology. The parameters investigated are defect extend, defect thickness and perfusion reduction of the defect. The images have been obtained through Monte Carlo Simulations with the program SIMIND. Results show that acceptable size resolution is obtained for defects with an extend over 25×25mm. When thickness and perfusion reduction are both unknown, the imaging results are confounding. In this work, thickness and perfusion reduction cannot be differentiated. If one of the variables is known (thickness or perfusion reduction), imaging results can differentiate between the other unknown variable.

Solid heart defects were designed to simulate regions of various contrast agent concentration by simply being immersed in a container with a radiopharmaceutical solution. The design was tested and verified by Monte Carlo simulation. Preliminary experimental results were taken on a gamma camera. The lower radiopharmaceutical concentrations were obtained by removing a certain volume of material, isotropically, from a solid cube of perspex material. The resolution of the imaging modality does not resolve the structure of the cube and the carved cube appears as a region of lower radiopharmaceutical concentration. It is aso verified with Monte Carlo simulations, obtaining profiles across low radiopharmaceutical concentration areas that vary by less than 3%. The preliminary imaging results confirmed that the gamma camera could not resolve the internal structure of the carved cube and that partial volume effect resulted in image intensity reduction.

The International Conference on Image Optimisation in Nuclear Medicine was held at the Atlantica Aeneas Resort in Ayia Napa, Cyprus between 23–26 March 2011. It was organised in the framework of the research project "Optimising Diagnostic Value in SPECT Myocardial Perfusion Imaging" (YΓEΙΑ/ΔYΓEΙΑ/0308/11), funded by the Cyprus Research Promotion Foundation and the European Regional Development Fund, to present the highlights of the project, discuss the progress and results, and define future related goals. The aim of this International Conference was to concentrate on image optimization approaches in Nuclear Medicine. Experts in the field of nuclear medicine presented their latest research results, exchanged experiences and set future goals for image optimisation while balancing patient dose and diagnostic value. The conference was jointly organized by the Frederick Research Centre in Cyprus, the Department of Medical and Public Health Services of the Cyprus Ministry of Health, the Biomedical Research Foundation in Cyprus and the AGH University of Science and Technology in Poland. It was supported by the Cyprus Association of Medical Physics and Biomedical Engineering, and the Cyprus Society of Nuclear Medicine. The conference was held under the auspices of the European Federation of Organisations for Medical Physics and the European Association of Nuclear Medicine. The conference scientific programme covered several important topics such as functional imaging; image optimization; quantification for diagnosis; justification; simulations; patient dosimetry, staff exposures and radiation risks; quality assurance and clinical audit; education, training and radiation protection culture; hybrid systems and image registration; and new and competing technologies. The programme consisted of 13 invited and keynote presentations as well as workshops, round table discussions and a number of scientific sessions. A total of 51 speakers presented their research and results to more than 150 participants from 14 countries. During the conference, exhibitors presented medical equipment used in nuclear medicine. We gratefully acknowledge the financial support of the Cyprus Research Promotion Foundation, the European Regional Development Fund and the Cyprus Biomedical Research Foundation. Also, we appreciate the support of the various local sponsors listed in the conference programme. We would like to express our sincere thanks and gratitude to the organising committee, the scientific committee and the supporting professional organizations for the success of the conference. We also thank all of speakers for their excellent contributions, all the participants for their input, and the exhibitors for their valuable presentations. Special thanks go to Demetris Kaolis, Maria Christofidou, Isabelle Chrysanthou, Charalambos Yiannakkaras, Ourania Demetriadou, and Elena Christofidou for their invaluable contribution to the conference. The conference volume consists of 26 selected proceedings papers. We would like to thank all of the authors for their time and genuine efforts and the reviewers for their fruitful comments. The Conference Chairpersons Stelios Christofides and Yiannis Parpottas