Quantum Tokens for Digital Signatures

The fisherman caught a quantum fish. "Fisherman, please let me go", begged the fish, "and I will grant you three wishes". The fisherman agreed. The fish gave the fisherman a quantum computer, three quantum signing tokens and his classical public key. The fish explained: "to sign your three wishes, use the tokenized signature scheme on this quantum computer, then show your valid signature to the king, who owes me a favor". The fisherman used one of the signing tokens to sign the document "give me a castle!" and rushed to the palace. The king executed the classical verification algorithm using the fish's public key, and since it was valid, the king complied. The fisherman's wife wanted to sign ten wishes using their two remaining signing tokens. The fisherman did not want to cheat, and secretly sailed to meet the fish. "Fish, my wife wants to sign ten more wishes". But the fish was not worried: "I have learned quantum cryptography following the previous story (The Fisherman and His Wife by the brothers Grimm). The quantum tokens are consumed during the signing. Your polynomial wife cannot even sign four wishes using the three signing tokens I gave you". "How does it work?" wondered the fisherman. "Have you heard of quantum money? These are quantum states which can be easily verified but are hard to copy. This tokenized quantum signature scheme extends Aaronson and Christiano's quantum money scheme, which is why the signing tokens cannot be copied". "Does your scheme have additional fancy properties?" the fisherman asked. "Yes, the scheme has other security guarantees: revocability, testability and everlasting security. Furthermore, if you're at sea and your quantum phone has only classical reception, you can use this scheme to transfer the value of the quantum money to shore", said the fish, and swam away.Comment: Added illustration of the abstract to the ancillary file

Unravelling plant-microbe-microbe dynamics using Arabidopsis thaliana and synthetic communities of Pseudomonas

Organismen befinden sich in ständiger Wechselwirkung und beeinflussen sich gegenseitig, im Zuge ihres eigenen Lebenszyklusses und im Zusammenhang von evolutionären Aspekten. Die Beziehung zwischen Wirt und seinem darauf lebenden Mikroben kann spontane und langfristige Wirkungen auf die Gesundheits des Wirtes haben. Ob die kolonisierten Mikroben gute oder schlechte Einwirkungen auf den Wirt haben, hängt mit den Wechselwirkungen der Mikroben zusammen. Überstimulation von pathogenen Mikroben wirken sich negativ auf die Gesundheit des Wirtes aus. Wohingegen schützende Mikroben eine schützende Wirkung auf den Wirt ausüben können, indem sie das Wachstum von Pathogenen hemmen. Zusammen mit dem Immunsystem des Wirtes und der komplexen Dynamik von Mikrob-Mikrob Interaktionen entsteht ein Fitness Gleichgewicht zwischen dem Wirt und seinen Mikroben. Der Fokus hier liegt auf der Dynamik zwischen Pflanzen und seinen Mikroben. Phytopathogene schädigen die globale Produktion von Nutzpflanzen, dennoch ist es unklar, wie natürliche Umgebungen diese abwehren. Diese Thesis, befasst sich mit den Interaktionen zwischen Wirt-Mikrob-Mikrob an Arabidopsis thaliana und seinen assoziierenden Pseudomonas Genus, genauer eine Kollektion von 1.524 Pseudomonas Spezien die auf derselben Pflanze sowie von derselben geografischen Region isoliert wurden. Das erste Kapitel umfasst die synergistischen Interaktionen zwischen unterschiedlichen zusammenlebenden pathogenen und kommensalen Pseudomonas Spezien, die auf unterschiedlichen Arabidopsis thaliana Linien vorkommen. Die synthetischen Gesellschaften wurden basierend auf ihr Genom mit unterschiedlichen Barcoden markiert, dadurch konnte ich die Fülle der individuellen Isolaten im Bezug auf die Gesellschaften analysieren. Aufgebaut waren die Gesellschaften in nur kommensal, nur Pathogenen und gemischen kommensal und pathogenen Gesellschaften. Die Einführung von kommensalen Mikroben hemmen die pathogenen Mikroben und können dadurch die pflanzliche Biomasse schützen. Diese Pflanzen schützenden Wirkungen wurden wurde weiter untersucht mit zwischen bakteriellen Interaktionen und dem Wirts Transkriptom. Daraus schloss ich, dass der Pflanzenschutz sich unterscheidet zwischen den unterschiedlichen Pflanzen Genotypen. Dies bedeutet, dass der Wirt unterschiedliche schützende Interaktionen einhergeht. Zu guter letzt, beobachtete ich, die aehnliche Genotyp spezifischen Effekte auf der mikrobiellen Seite: wie ein einzelnes pathogenes Pseudomonas Isolat verschiedene schützende Effekte hervorrufen kann. Im zweiten Kapitel, wurden die schützenden kommensalen Pseudomonas Isolate genauer untersucht auf (I) ihre Häufigkeit, (II) die spezifischen Taxa, und (III) die bakteriellen Elemente. Dafür wurden verschiedene systematische Co-infektionen von jedem 99 lokal isolierten kommensalen und pathogenen Pseudomonas Isolate miteinander zusammengestellt. Die Mehrheit von diesen wilden kommensalen Pseudomonas Isolaten schützen die Pflanzen zu einem gewissen Masse. Besonders auffallend war eine spezifische taxonomische Gruppe, die jedoch Variationen aufzeigte von ihrer schützenden Wirkung mit sehr nah verwandten Spezien, selbst wenn sie in derselben Gruppe auftauchten. Eine Genomweite-assoziation Studie (GWAS) zeigte, dass schützende Wirkung zurückzuführen ist zu einem taxon-spezifischen Gen Sets, die innerhalb einer orthologen Gruppe liegen. Diese Sets sind ein Indiz für die unterschiedlichen Mechanismen die zum Pflanzenschutz führen. Laut den Gen Beschreibungen, sind die Gensets relevant für unterschiedliche Schutzfunktionen, wie die Aufnahme von Eisen, Antibiose, und Motilität. Verschiedene Gendeletionen bestätigen die Konnektivität zwischen Pflanzenschutz und drei Genen die relevant sind für die Aufnahme von Eisen und eins dass zur Bildung von Biofilm beiträgt. Zusammenfassend, diese Arbeit erweitert unser Wissen wie genetische Diversität einen Effekt hat auf mikrobielle und pflanzliche Ebene, im Sinne von unterschiedlichen Interaktionen und somit wurde einen weiteren Aspekt in diesem komplexen System entschlüsselt. Eine der Hauptaussage dieser Arbeit ist, dass kommensale Bakterien einen entscheidenden Faktor zum Pflanzenschutz beitragen, durch die wett kämpferischen Interaktionen zwischen den Mikroben und durch die Aktivierung des Immunsystems vom Wirt. Die Anwendung von kommensalen Mikroben um Pathogene zu kontrollieren kann die Nachhaltigkeit der globalen Landwirtschaft stärken.Organisms affect and shape each other, both during their own lifespans and in evolutionary terms. The relationship between a host and its colonizing microbes can have major immediate and long-term effects on host health. Whether the colonizing microbes have a good impact or a bad one depends in part on how those microbes interact with each other. Overproliferation of pathogenic microbes is associated with negative impacts on the host health. This can be countered by protective microbes, which may suppress pathogenic ones. Taken together with the host immune system, the complicated host-microbe-microbe dynamics form a balance of fitness between the host and its microbes. Of specific interest are the dynamics between plants and microbes. Phytopathogens harm global agricultural production, yet are often somehow held in check in wild settings. In this thesis, I am studying the plant-microbe-microbe interface using Arabidopsis thaliana and its associated bacterial genus Pseudomonas, leveraging a collection of 1,524 Pseudomonas strains which were isolated from plants of the same geographic region. In the first chapter, I focus on synergistic effects, studying the interactions between multiple coexisting pathogenic and commensal Pseudomonas strains with a panel of Arabidopsis thaliana accessions. By employing synthetic communities of genome-barcoded strains, I monitored the abundance of individual isolates in the context of communities, including exclusively commensal, exclusively pathogenic, and mixed commensal and pathogenic communities. I revealed that the inclusion of commensal members led to inhibition of pathogens, preventing the harmful effect on plant biomass. I associated these protective interactions with both microbe-microbe interactions and with the host transcriptomic signature. I found that the extent of plant protection varied with host genotype, further highlighting the role of the host in mediating protective interactions. Finally, I unravelled similar genotype-specific effects on the microbial side, presenting how an individual Pseudomonas pathogenic isolate caused this differential protection effect. In the second chapter, I investigate (i) the prevalence of protection against pathogens by commensal Pseudomonas, (ii) the taxonomic specificity of such protection and (iii) the bacterial elements in commensal Pseudomonas that lead to protection. To address these questions, I made systematic co-infections, pairing each of ninety-nine locally-isolated commensal isolates with a local Pseudomonas pathogen. The majority of these wild commensal Pseudomonas protected the plant to some extent. In particular, one taxonomic group was enriched for protective isolates. However, the ability to protect the plant varied between closely related strains, even within this protective group. I leveraged this variation to conduct a genome-wide association study (GWAS), pinpointing gene orthologs in presence-absence variation that are associated with the protective ability. Instead of a universal set, I found taxon-specific gene sets. According to gene annotation, these sets indicated different mechanisms of protection, including iron-uptake, antibiosis, and motility. Using gene deletion, I validated the role of a subset of genes, confirming a link between plant protection with three iron-uptake genes and one biofilm-related gene. Collectively, this work advances our knowledge about how genetic diversity in both the microbe and the host affects the outcome of the interaction, disentangling different aspects of this complex system. Among the main conclusions of this work is that commensal bacteria are an important factor in maintaining plant health, acting via multiple competitive microbe-microbe mechanisms and via induction of the host immune response. Ultimately, application of such commensal bacteria to control pathogens may sustainably improve global agriculture

Quantum Tokens for Digital Signatures

The fisherman caught a quantum fish. Fisherman, please let me go , begged the fish, and I will grant you three wishes . The fisherman agreed. The fish gave the fisherman a quantum computer, three quantum signing tokens and his classical public key. The fish explained: to sign your three wishes, use the tokenized signature scheme on this quantum computer, then show your valid signature to the king, who owes me a favor . The fisherman used one of the signing tokens to sign the document give me a castle! and rushed to the palace. The king executed the classical verification algorithm using the fish\u27s public key, and since it was valid, the king complied. The fisherman\u27s wife wanted to sign ten wishes using their two remaining signing tokens. The fisherman did not want to cheat, and secretly sailed to meet the fish. Fish, my wife wants to sign ten more wishes . But the fish was not worried: I have learned quantum cryptography following the previous story (The Fisherman and His Wife by the brothers Grimm). The quantum tokens are consumed during the signing. Your polynomial wife cannot even sign four wishes using the three signing tokens I gave you . How does it work? wondered the fisherman. Have you heard of quantum money? These are quantum states which can be easily verified but are hard to copy. This tokenized quantum signature scheme extends Aaronson and Christiano\u27s quantum money scheme, which is why the signing tokens cannot be copied . Does your scheme have additional fancy properties? the fisherman asked. Yes, the scheme has other security guarantees: revocability, testability and everlasting security. Furthermore, if you\u27re at sea and your quantum phone has only classical reception, you can use this scheme to transfer the value of the quantum money to shore , said the fish, and swam away

Associations Between Perception of Parental Behavior and “Person Picking an Apple From a Tree” Drawings Among Children With and Without Special Educational Needs (SEN)

The present study examines and compares associations between perceptions of parental acceptance/rejection in 191 Greek school age children (84 inclusion class students and 107 typical class students, age range 10–12), and their “Person Picking an Apple from a Tree” (PPAT) drawings. Perception of parental behavior was measured by the “Parental Acceptance-Rejection Questionnaire” (Rohner and Khaleque, 2005). Drawing content was analyzed quantitatively according to a reliable rating system called the Symbolic Content in PPAT drawings (SC-PPAT: Bat Or et al., 2014, 2017). We employed k-means cluster analysis and obtained three relatively discrete PPAT scripts. Drawing content elements and scripts were found to be associated with children’s perceptions of parental behavior; these associations were found mainly among children with special educational needs (SEN) and boys. Results are discussed in terms of children’s subjective experience, clinical implications, and future research directions

Making cheaper labor: Domestic outsourcing and development in the Galilee

Middle Eastern Studie

Visual Expressions of Children’s Strengths, Difficulties and Wishes in Person Picking an Apple from a Tree Drawings among Preschoolers Living in Areas of Persistent Political Violence

The present study sought to inquire into the subjective experience of 156 preschoolers (age 4–6.9 years) living in an area of political violence in Israel (on the border with the Gaza Strip) during a period of massive bombing. Children were invited to draw a Person Picking an Apple from a Tree (PPAT), and were interviewed on their sense of self-potency using the CAMP, a measure of potency. Teachers were asked to report problems in executive functions using a few BRIEF scales; and mothers filled out a questionnaire for maternal distress (BSI), a measure of their child strengths and difficulties (SDQ), and were asked to provide their assessment regarding the extent to which their child was exposed to political violence. Findings reveal associations between mothers’ distress, the degree of exposure of their child to trauma, and the child’s emotional symptoms. PPAT analysis identified four main factors: Tree Generosity, Person Agency, Vividness, and As-Real-R. Positive associations were found between self-potency and the main factors of the drawings; negative associations were found between the child’s difficulties in executive functions and the drawing’s four main factors; and two small negative associations were found between the child’s emotional symptoms and Tree Generosity and As-Real-R factors. The following associations were found within each gender group: mothers’ depression degree was associated with boy’s Tree Generosity, and mother’s perceptions of their girl’s exposure to trauma was related to Person Agency, Tree Generosity, and As-Real-R factors; furthermore, a significant difference was found between the narrative focus of drawings in this sample and the narrative focus of drawings of a sample of the same age group from a non-war zone. In addition, narrative focus was found to be related to children’s self-potency. The discussion deals with the study’s findings through the prism of developmental psychology, self-agency, object-relations, and art-therapy theories