The Kodaira dimension of Siegel modular varieties of genus 3 or higher

We consider the moduli space $A_{pol}(n)$ of (non-principally) polarised abelian varieties of genus $g\geq3$ with coprime polarisation and full level-$n$ structure. Based upon the analysis of the Tits building in math/0405321, we give an explicit lower bound on $n$ that is sufficient for the compactified moduli space to be of general type if one further explicit condition is satisfied.Comment: 22 page

Affordances Of Interorganisational Information Systems (IOIS) – A Pharmacist’S Perspective

The IS research community is still struggling with a proper theorisation of the IT-artefact. The debate manifests in questions regarding the effect of IT (Markus and Silver 2008), the identity of systems (Reimers et al. 2009), or more generally the appropriate theoretical tools for studying these systems. Part of the quest for theorising the IT-artefact is whether technology possesses inherent properties affecting human behaviour or if technology is a product of a social construction? The notion of ‘affordance’ seeks to overcome this dualism by positioning itself as a relational concept. An ‘affordance’ is mutually constituted by subject and object. This paper uses the notion of ‘affordance’ to analyse an electronic ordering system between pharmacies and wholesalers. The paper aims to scrutinise different means of ordering from a pharmacist’s perspective. In doing so, benefits as well as challenges of using ‘affordances’ to study the IT-artefact are exemplified. The paper demonstrates that ‘affordance’ as an analytical tool offers a much richer analysis of empirical data than a mere description of functional properties would allow. Despite its merits, the paper finds that the notion of ‘affordance’ requires theoretical extensions in order to render it more suitable for the study of interorganisational information systems

Technical Feasibility of MR-Integrated Proton Therapy: Beam Deflection and Image Quality

Es wird erwartet, dass die Integration der Magnetresonanztomografie (MRT) in die Protonentherapie die Treffgenauigkeit bei der Strahlentherapie für Krebserkrankungen deutlich verbessern wird. Besonders für Tumoren in beweglichen Organen des Thorax oder des Abdomens könnte die MRT-integrierte Protonentherapie (MRiPT) eine Synchronisierung der Bestrahlung mit der Tumorposition ermöglichen, was zu einer verminderten Normalgewebsdosis und weniger Nebenwirkungen führen könnte. Bis heute ist solch eine Integration jedoch aufgrund fehlender Studien zu potenziellen gegenseitigen Störeinflüssen dieser beiden Systeme nicht vollzogen worden. Diese Arbeit widmete sich zwei solcher Störeinflüsse, und zwar der Ablenkung des Protonenstrahls im Magnetfeld des MRT- Scanners, und umgekehrt, dem Einfluss der elekromagnetischen Felder der Protonentherapieanlage und des Protonenstrahls selbst auf die MRT-Bilder. Obwohl vorangegangene Studien den derzeitigen Konsens aufgezeigt haben, dass die Trajektorie eines abgebremsten Protonenstrahls im homogenen Phantom in einem transversalen Magnetfeld vorhersagbar ist, zeigte sich im quantitativen Vergleich der publizierten Modelle, der im ersten Teil dieser Arbeit vorgestellt wurde, dass die Vorhersagen dieser Modelle nur für eine begrenzte Anzahl von Kombinationen aus Magnetfeldstärke und Protonenenergie übereinstimmen. Die Schwächen bestehender analytischer Modelle wurden deshalb analysiert und quantifiziert. Kritische Annahmen und die mangelnde Anwendbarkeit auf realistische, d.h. inhomogene Magnetfeldstärken und Patientengeometrien wurden als Hauptprobleme identifiziert. Um diese zu überwinden, wurde ein neues semianalytisches Modell namens RAMDIM entwickelt. Es wurde gezeigt, dass dieses auf realistischere Fälle anwendbar und genauer ist als existierende analytische Modelle und dabei schneller als Monte-Carlo-basierte Teilchenspursimulationen. Es wird erwartet, dass dieses Modell in der MRiPT Anwendung findet zur schnellen und genauen Ablenkungsberechnung, zur Betrahlungsplanoptimierung und bei der MRT-geführten Strahlnachführung. In einem zweiten Schritt wurde die magnetfeldinduzierte Protonenstrahlablenkung in einem gewebeähnlichen Material durch Filmdosimetrie erstmalig gemessen und mit Monte-Carlo-Simulationen verglichen. In einem transversalen Magnetfeld einer Flussdichte von 0,95 T wurde experimentell gezeigt, dass die laterale Versetzung des Bragg-Peaks für Protonenenergien zwischen 80 und 180 MeV in PMMA zwischen 1 und 10 mm liegt. Die Retraktion des Bragg-Peaks war ≤ 0,5 mm. Es wurde gezeigt, dass die gemessene Versetzung des Bragg-Peaks innerhalb von 0,8 mm mit Monte-Carlo-basierten Vorhersagen übereinstimmt. Diese Ergebnisse weisen darauf hin, dass die Protonenstrahlablenkung durch Monte-Carlo-Simulationen genau vorhersagbar ist und damit der Realisierbarkeit der MRiPT nicht im Wege steht. Im zweiten Teil dieser Arbeit wurde erstmalig ein MRT-Scanner in eine Protonenstrahlführung integriert. Hierfür wurde ein offener Niederfeld-MRT-Scanner am Ende einer statischen Forschungsstrahlführung einer Protonentherapieanlage platziert. Die durch das statische Magnetfeld des MRT-Scanners hervorgerufene Strahlablenkung wurde bei der Ausrichtung des MRT-Scanners berücksichtigt. Die sequenzabhängigen, veränderlichen Gradientenfelder hatten keinen messbaren Einfluss auf das transversale Strahlprofil hinter dem MRT-Scanner. Die Magnetfeldhomogenität des Scanners lag innerhalb der Herstellervorgaben und zeigte keinen relevanten Einfluss von Rotationen der Protonengantry im benachbarten Bestrahlungsraum. Eine magnetische Abschirmung war zum gleichzeitigen Betrieb des MRT-Scanners und der Protonentherapieanlage nicht notwendig. Dies beweist die Machbarkeit gleichzeitiger Bestrahlung und Bildgebung in einem ersten MRiPT Aufbau. Die MRT-Bildqualität des Aufbaus wurde darauffolgend anhand eines angepassten Standardprotokolls aus Spin-Echo- und Gradienten-Echo-Sequenzen quantifiziert und es wurde gezeigt, dass die Bildqualität sowohl ohne als auch mit gleichzeitiger Bestrahlung hinreichend ist. Alle bestimmten geometrischen Parameter stimmten mit den physikalischen Abmessungen des verwendeten Phantoms innerhalb eines Bildpixels überein. Wie es für Niederfeld-MRT-Scanner üblich ist, war das Signal-Rausch-Verhältnis (SNR) der MRT-Bilder gering, was im Vergleich zu den Standardkriterien zu einer geringen Bildhomogenität und zu einem hohen Geisterbildanteil im Bild führte. Außerdem wurde aufgrund von Unsicherheiten in der Hochfrequenzkalibrierung des MRT-Scanners eine starke Schwankung der vertikalen Phantomposition mit einem Interquartilabstand von bis zu 1,5 mm beobachtet. T2*-gewichtete Gradientenechosequenzen zeigten zudem aufgrund von Magnetfeldinho- mogenitäten relevante ortsabhängige Bildverzerrungen. Es wurde gezeigt, dass die meisten Bildqualitätsparameter mit und ohne gleichzeitige Betrahlung äquivalent sind. Es wurde jedoch ein signifikanter Betrahlungseinfluss in Form von einer vertikalen Bildverschiebung und einer Verminderung des SNR beobachtet, die durch eine Änderung im Magnetfeld des MRT-Scanners erklärt werden können, welche durch zu diesem Feld parallel ausgerichtete Komponenten im Fernfeld der Strahlführungsmagneten hervorgerufen wird. Während das verminderte SNR vermutlich irrelevant ist (Dif- ferenz im Median ≤ 1,5), ist die sequenzabhängige Bildverschiebung (Differenz im Median bis zu 0,7 mm) nicht immer vernachlässigbar. Diese Ergebisse zeigen, dass die MRT-Bilder durch gleichzeitige Bildgebung nicht schwerwiegend verfälscht werden, dass aber eine dedizierte Optimierung der Hochfrequenzkalibrierung und der MRT-Bildsequenzen notwendig ist. Im letzten Teil der Arbeit wurde gezeigt, dass ein stromabhängiger Einfluss des Protonenstrahls auf MRT-Bilder eines Wasserphantoms durch zwei verschiedene MRT-Sequenzen messbar gemacht und zur Reichweiteverifikation genutzt werden kann. Der Effekt war in verschiedenen Flüssigkeiten, jedoch nicht in viskosen und festen Materialen, nachweisbar und wurde auf Hitzekonvektion zurückgeführt. Es wird erwartet, dass diese Methode in der MRiPT für Konstanztests der Protonenreichweite bei der Maschinenqualitätssicherung nützlich sein wird. Zusammenfassend hat diese Arbeit die Genauigkeit der Vorhersage der Strahlablenkung quantifiziert und verbessert, sowie Potenzial und Realisierbarkeit einer gleichzeitigen MRT-Bildgebung und Protonenbestrahlung gezeigt. Die weitere Entwicklung eines ersten MRiPT-Prototyps ist demnach gerechtfertigt.:List of Figures v List of Tables vii 1 General Introduction 1 2 State of the Art: Proton Therapy and Magnetic Resonance Imaging 3 2.1 Proton Therapy 4 2.1.1 Physical Principle 4 2.1.2 Beam Delivery 7 2.1.3 Motion Management and the Role of Image Guidance 10 2.2 Magnetic Resonance Imaging 14 2.2.1 Physical Principle 14 2.2.2 Image Generation by Pulse Sequences 18 2.2.3 Image Quality 21 2.3 MR-Guided Radiotherapy 24 2.3.1 Offline MR Guidance 24 2.3.2 On-line MR Guidance 25 2.4 MR-Integrated Proton Therapy 28 2.4.1 Aims of this Thesis 32 3 Magnetic Field-Induced Beam Deflection and Bragg Peak Displacement 35 3.1 Analytical Description 36 3.1.1 Review of Analytical Models 36 3.1.2 New Model Formulation 41 3.1.3 Evaluation of Analytical and Numerical Models 44 3.1.4 Discussion 51 3.2 Monte Carlo Simulation and Experimental Verification 54 3.2.1 Verification Setup 54 3.2.2 Monte Carlo Simulation 56 3.2.3 Experimental Verification 60 3.2.4 Discussion 61 3.3 Summary 63 4 Integrated In-Beam MR System: Proof of Concept 65 4.1 Integration of a Low-Field MR Scanner and a Static Research Beamline 65 4.1.1 Proton Therapy System 66 4.1.2 MR Scanner 66 4.1.3 Potential Sources of Interference 67 4.1.4 Integration of Both Systems 68 4.2 Beam and Image Quality in the Integrated Setup 70 4.2.1 Beam Profile 70 4.2.2 MR Magnetic Field Homogeneity 72 4.2.3 MR Image Quality - Qualitative In Vivo and Ex Vivo Test 74 4.2.4 MR Image Quality - Quantitative Phantom Tests 77 4.3 Feasibility of MRI-based Range Verification 86 4.3.1 MR Sequences 86 4.3.2 Proton Beam Parameters 88 4.3.3 Target Material Dependence 91 4.3.4 Discussion 92 4.4 Summary 96 5 Discussion and Future Perspectives 99 6 Summary/Zusammenfassung 105 6.1 Summary 105 6.2 Zusammenfassung 108 Bibliography I Supplementary Information XXIX A Beam Deflection: Experimental Measurements XXIX A.1 Setup XXIX A.2 Film Handling and Evaluation XXX A.3 Uncertainty Estimation XXX B Beam Deflection: Monte Carlo Simulations XXXIII B.1 Magnetic Field Model XXXIII B.2 Uncertainty Estimation XXXIV C Integrated MRiPT Setup XXXVI C.1 Magnetic Field Map XXXVI C.2 Sequence Parameters XXXVI C.3 Image Quality Parameters XLII C.4 Range Verification Sequences XLIIThe integration of magnetic resonance imaging (MRI) into proton therapy is expected to strongly increase the targeting accuracy in radiation therapy for cancerous diseases. Especially for tumours situated in mobile organs in the thorax and abdomen, MR-integrated proton therapy (MRiPT) could enable the synchronisation of irradiation to the tumour position, resulting in less dose to normal tissue and reduced side effects. However, such an integration has been hindered so far by a lack of scientific studies on the potential mutual interference between the two components. This thesis was dedicated to two of these sources of interference, namely the deflection of the proton beam by the magnetic field of the MR scanner and, vice versa, alterations of the MR image induced by the electromagnetic fields of the proton therapy facility and by the beam itself. Although previous work has indicated that there is general consensus that the trajectory of a slowing down proton beam in a homogeneous phantom inside a transverse magnetic field is predictable, a quantitative comparison of the published methods, as presented in the first part of this thesis, has shown that predictions of different models only agree for certain proton beam energies and magnetic flux densities. Therefore, shortcomings of previously published analytical methods have been analysed and quantified. The inclusion of critical assumptions and the lack of applicability to realistic, i.e. non-uniform, magnetic flux densities and patient anatomies have been identified as main problems. To overcome these deficiencies, a new semi-analytical model called RAMDIM has been developed. It was shown that this model is both applicable to more realistic setups and less assumptive than existing analytical approaches, and faster than Monte Carlo based particle tracking simulations. This model is expected to be useful in MRiPT for fast and accurate deflection estimations, treatment plan optimisation, and MR-guided beam tracking. In a second step, the magnetic field-induced proton beam deflection has been measured for the first time in a tissue-mimicking medium by film dosimetry and has been compared against Monte Carlo simulations. In a transverse magnetic field of 0.95 T, it was experimentally shown that the lateral Bragg peak displacement ranges between 1 mm and 10 mm for proton energies between 80 and 180 MeV in PMMA. Range retraction was found to be ≤ 0.5 mm. The measured Bragg peak displacement was shown to agree within 0.8 mm with Monte Carlo simulations. These results indicate that proton beam deflection in a homogeneous medium is accurately predictable for intermediate proton beam energies and magnetic flux densities by Monte Carlo simulations and therefore not impeding the feasibility of MRiPT. In the second part of this thesis, an MR scanner has been integrated into a proton beam line for the first time. For this purpose, an open low-field MR scanner has been placed at the end of a fixed horizontal proton research beam line in a proton therapy facility. The beam deflection induced by the static magnetic field of the scanner was taken into account for alignment of the beam and the FOV of the scanner. The pulse sequence-dependent dynamic gradient fields did not measurably affect the transverse beam profile behind the MR scanner. The MR magnetic field homogeneity was within the vendor’s specifications and not relevantly influenced by the rotation of the proton gantry in the neighbouring treatment room. No magnetic field compensation system was required for simultaneous operation of the MR scanner and the proton therapy system. These results proof that simultaneous irradiation and imaging is feasible in an in-beam MR setup. The MR image quality of the in-beam MR scanner was then quantified by an adapted standard protocol comprising spin and gradient echo imaging and shown to be acceptable both with and without simultaneous proton beam irradiation. All geometrical parameters agreed with the mechanical dimensions of the used phantom within one pixel width. As common for low-field MR scanners, the signal-to-noise ratio (SNR) of the MR images was low, which resulted in a low image uniformity and a high ghosting ratio in comparison to the standardised test criteria. Furthermore, a strong fluctuation of the vertical phantom position due to uncertainties in the pre-scan frequency calibration was observed, with an interquartile range of up to 1.5 mm. T2*-weighted gradient echo images showed relevant nonuniform deformations due to magnetic field inhomogeneities. Most image quality parameters were shown to be equivalent with and without simultaneous proton beam irradiation. However, a significant influence of simultaneous irradiation was observed as a shift of the vertical phantom position and a decrease in the SNR, both of which can be explained by a change in the B0 field of the MR scanner induced by components of the fringe field of the beam line magnets directed parallel to B0 . While the decrease in SNR is not expected to be relevant (median differences were within 1.5 ), the sequence-dependent phantom shift (median differences of up to 0.7 mm) can become non-negligible. These results show that the MR images are not severely distorted by simultaneous irradiation, but a dedicated optimisation of the pre-scan RF calibration and the MR sequences is required for MRiPT. Lastly, a current-dependent influence of the proton beam on the MR image was shown to be measurable in water in two different MR sequences, which allowed for range verification measurements. The effect was observed in different liquids but not in highly viscose and solid materials, and most probably induced by heat convection. This method is expected to be useful in MRiPT for consistency tests of the proton range during machine-specific quality assurance. In conclusion, this work has improved and quantified the accuracy of beam deflection predictions and shown the feasibility and potential of in-beam MR imaging, justifying further research towards a first MRiPT prototype.:List of Figures v List of Tables vii 1 General Introduction 1 2 State of the Art: Proton Therapy and Magnetic Resonance Imaging 3 2.1 Proton Therapy 4 2.1.1 Physical Principle 4 2.1.2 Beam Delivery 7 2.1.3 Motion Management and the Role of Image Guidance 10 2.2 Magnetic Resonance Imaging 14 2.2.1 Physical Principle 14 2.2.2 Image Generation by Pulse Sequences 18 2.2.3 Image Quality 21 2.3 MR-Guided Radiotherapy 24 2.3.1 Offline MR Guidance 24 2.3.2 On-line MR Guidance 25 2.4 MR-Integrated Proton Therapy 28 2.4.1 Aims of this Thesis 32 3 Magnetic Field-Induced Beam Deflection and Bragg Peak Displacement 35 3.1 Analytical Description 36 3.1.1 Review of Analytical Models 36 3.1.2 New Model Formulation 41 3.1.3 Evaluation of Analytical and Numerical Models 44 3.1.4 Discussion 51 3.2 Monte Carlo Simulation and Experimental Verification 54 3.2.1 Verification Setup 54 3.2.2 Monte Carlo Simulation 56 3.2.3 Experimental Verification 60 3.2.4 Discussion 61 3.3 Summary 63 4 Integrated In-Beam MR System: Proof of Concept 65 4.1 Integration of a Low-Field MR Scanner and a Static Research Beamline 65 4.1.1 Proton Therapy System 66 4.1.2 MR Scanner 66 4.1.3 Potential Sources of Interference 67 4.1.4 Integration of Both Systems 68 4.2 Beam and Image Quality in the Integrated Setup 70 4.2.1 Beam Profile 70 4.2.2 MR Magnetic Field Homogeneity 72 4.2.3 MR Image Quality - Qualitative In Vivo and Ex Vivo Test 74 4.2.4 MR Image Quality - Quantitative Phantom Tests 77 4.3 Feasibility of MRI-based Range Verification 86 4.3.1 MR Sequences 86 4.3.2 Proton Beam Parameters 88 4.3.3 Target Material Dependence 91 4.3.4 Discussion 92 4.4 Summary 96 5 Discussion and Future Perspectives 99 6 Summary/Zusammenfassung 105 6.1 Summary 105 6.2 Zusammenfassung 108 Bibliography I Supplementary Information XXIX A Beam Deflection: Experimental Measurements XXIX A.1 Setup XXIX A.2 Film Handling and Evaluation XXX A.3 Uncertainty Estimation XXX B Beam Deflection: Monte Carlo Simulations XXXIII B.1 Magnetic Field Model XXXIII B.2 Uncertainty Estimation XXXIV C Integrated MRiPT Setup XXXVI C.1 Magnetic Field Map XXXVI C.2 Sequence Parameters XXXVI C.3 Image Quality Parameters XLII C.4 Range Verification Sequences XLI

Evaluation of Cell Lysis Techniques for Direct Amplification of Sexual Assault Samples

Sexual assault is one of the most common crimes committed today with a delay in sample processing, resulting in the “rape kit backlog”. The traditional method to extract DNA from these samples containing both male and female DNA is a differential extraction; taking hours to process. This study examined a variety of different cell lysis techniques to develop a method which can consistently generate high-quality profiles at a fast rate and with low volumes when compared to the currently used method in our laboratory. Six lysis methods, in addition to the currently used forensicGEM™ Sperm kit, were performed on semen swabs from ten donors. Quantification using Investigator® Quantiplex HYres revealed all lysis methods performed comparably to the control method (p\u3e0.06). Samples were amplified using the Promega™ PowerPlex® Fusion 5C System with a target DNA template input of 0.25ng where three alternative methods were found to produce similar results to that of the control: Casework Direct, alkaline lysis, and NP-40 lysis buffer due to their increase in peak heights and their interlocus balance being similar to the control (CV=0.38) or lower. Similar results were reported when STR amplification was repeated with samples metering a specific volume to simulate sample processing on a microfluidic device. However, HGH cell lysis was also found to perform comparably to the control when this approach was performed. Overall, the data provided positive preliminary results for the use of alternative lysis techniques both for traditional in-tube assays, as well as the chip-based approach for a microfluidic device

Metaphysics of Change and Identity

Several authors have claimed the need of the IS community to theorize the IT-artifact. Additionally, phenomena of ‘change’ in all its facets assume a prominent role in information systems research. This paper is targeting at the intersection of research on change and the IT-artifact. The lack of longitudinal studies in the IS-literature has obscured the challenges of theorizing the IT-artifact over time. This paper raises the question under what conditions an IT-artifact persists through time as one and the same object. By exploring the metaphysical assumptions of our common understanding of the IT-artifact the inadequacy of current conceptualizations of change and IT is demonstrated. The paper shows that the commonly held identity bases on a substance philosophical viewpoint. A conceptualization of identity based on process philosophy is introduced as an alternative that avoids shortcomings of the former. Thereby, new means to study information systems and their evolution over time evolve

Theorizing the IT-Artifact in Inter-Organizational Information Systems: An Identity Perspective

Several authors have claimed the need of the IS community to theorize the IT-artifact as their core subject matter. In a research project on the evolution of inter-organizational information systems over large-time scales this lack of theorization became problematic. In fact it became evident that the notion of change or stability requires a sharper theorization of the artifact than currently found in the literature. As a result, this paper sets its aim to provide a new theoretical conceptualization of the IT-artifact in inter-organizational systems. The lack of sufficient theorization of the IT-artifact is established by analyzing several accounts of studies on information systems change in the literature. The notion of identity and its philosophical venue is being introduced as a promising requirement for theories of information systems change. Although not fully developed it is shown that it promises a more thorough analysis of IOIS in theory and in empirical studies. It provides guidance for theory development and empirical work not only in regard to IOIS but IS in general. Although not being prescriptive in nature the identity concept may be helpful in explaining systems failure

Organizational Identity as Perspective – Investigating the IT-artifact

The need of the IS-community to theorize the IT-artifact has been claimed by several authors. It has been somewhere between difficult and impossible to unequivocally agree on what the IT-artifact is. This paper argues that this is even more challenging when considering inter-organizational information systems (IOIS). After pointing to methodological and theoretical problems of researching IOIS this paper develops a different research approach. It proposes the notion of identity as a concept to study the IT-artifact. This paper works out a theoretical framework that blends the Gibsonian notion of affordance with that of organizational identity. In his work, Gibson emphasizes the importance of perspective. In order to account for different perceptions of affordances of the IT-artifact, organizational identity is discussed as an important element of perception. By combining the notions of affordance and organizational identity a new framework for studying IS in general and IOIS in particular is proposed

Testicular Carcinomas and Carcinoma of the Prostate

Testicular neoplasms are relatively rare with approximately two new cases per 100,000 male population occurring per year. The peak occurrence is between the ages of 20 and 40. Because of their highly malignant characteristics testicular neoplasms must be treated aggressively if cure is to be achieved

Towards contextualizing stressors in technostress research

The literature on technostress posits that information and communication technology (ICT) contributes to feelings of strain by increasing the speed of work, having to adapt to technological change, and/or the poor usability features of the ICT. Most technostress research builds on surveys distributed across organizations. Thus, stressor-related questions cannot differentiate between how strain might be experienced in different roles assumed in the workplace. This paper aims to investigate, by means of an experiment, how different roles in a work arrangement affect the perception of strain. Our results show that the mere quantity of tasks does not serve as a good predictor of strain. We posit that the perception of strain and stressors is influenced by the context in which the tasks are embedded. These findings underline the need to investigate the ways in which ICT alter

Syrian war at the crossroads: curbing arms flow, imposing a no-fly zone and opening al-Yarubiyan border crossing

Suspend the transfer of weapons, ammunition and military equipment to secondary conflict parties, such as Turkey and Saudi Arabia, to stop illegal re-transfers to the Syrian war zone. Existing national agreements to suspend certain arms exports to Turkey (2019) by Norway, Finland, the Netherlands, France, the United Kingdom and Germany, as well as the export moratoria of limited duration for Saudi Arabia (2018), should be extended to a comprehensive, not time-limited EU arms embargo. Many of the weapons that are re-exported to Syria are old arms, produced in former Yugoslavian countries or the Soviet Union. To date, partially uncontrolled and illegal stocks of old arms exist on the Balkans and in eastern European states. To prevent further proliferation of these weapons to Syria and other war zones, the European Commission should set up an initiative to buy and destroy these weapons. To stop the cycle of mass displacement and attacks against civilians, a UN-mandated no-fly zone must be established in northern Syria. If a no-fly zone is not successful in protecting civilians in northern Syria, a UN-mandated safe zone must also be considered and ultimately implemented. EU member states must call on the UN Security Council to vote for continuing humanitarian cross-border aid (UNSCR 2165) and to reopen the al-Yarubiyah border crossing with Iraq in north-eastern Syria to prevent the humanitarian situation from deteriorating further