Applications of Holography to Strongly Coupled Plasmas

We study several observables related to heavy quarks in strongly coupled plasmas using the gauge/gravity correspondence. Besides the AdS_5 space dual to N=4 supersymmetric Yang-Mills theory we consider large classes of theories obtained from various deformations of the AdS_5 space. Among them are theories that solve equations of motion of a 5-dimensional Einstein-Hilbert-scalar action. Specifically, we calculate the screening distance of a heavy quark-antiquark pair moving at constant velocity through the plasma, the running coupling defined via the free energy of such a static pair, and the energy radiation from a heavy quark forced into a circular motion in the plasma. We find that these observables show universal behaviour in large classes of theories. The screening distance in these classes of theories, that is the maximal distance for which a heavy quark-antiquark pair is bound, is found to be bounded from below by its value in N=4 super Yang-Mills theory.Comment: 8 pages, Talk presented by K. S. at Xth Quark Confinement and the Hadron Spectrum, October 8-12, 2012, Munic

Screening in Strongly Coupled Plasmas: Universal Properties from Strings in Curved Space

We use the gauge/gravity correspondence to study the screening of a heavy quark-antiquark pair in various strongly coupled plasmas. Besides N=4 super Yang-Mills theory and the corresponding AdS_5 space we also study theories obtained as deformations of AdS_5, among them in particular a class of deformations solving supergravity equations of motion. We consider the dependence of the screening distance on the velocity and the orientation of the pair in the plasma. The value of the screening distance in N=4 SYM is found to be a minimum in the class of theories under consideration for all kinematic parameters.Comment: 10 pages, Talk presented by C.E. at Gribov-80 Memorial Workshop, ICTP Trieste, Italy, May 201

Coordination and allocation on land markets under increasing scale economies and heterogeneous actors - An experimental study

Economies of scale and scope are often not exploited in Western agriculture. A general reason is probably that various types of transaction costs limit coordination among farmers. A more specific explanation is that coordination on land markets or machinery cooperation is difficult to achieve when farmers are heterogeneous as some kind of price differentiation is necessary for a Pareto-superior solution. This paper investigates experimentally such a coordination game with heterogeneous agents using an example inspired by agricultural land markets. The experimental findings suggest that a Pareto-optimal solution may not be found when agents are heterogeneous. The findings provide evidence for market failures and cooperation deficits as reasons for unexploited economies of scale in agriculture. Our findings are consistent with coordination failures that appear to be driven by behavioural factors such as anchoring-and-adjustment, inequity aversion, and a reverse form of winner’s curse.Land Markets, Coordination and Allocation, Experimental Economics, Agricultural and Food Policy, Farm Management, Land Economics/Use,

Applications of Holography to Strongly Coupled Plasmas

This thesis is concerned with the analysis of universal properties of several physical observables in strongly coupled plasmas as they are studied in heavy-ion collisions – for example at the LHC. The focus lies on the energy loss of a uniformly moving and of a rotating quark, the running coupling as defined via the free energy of static quark-antiquark (QQbar)-pairs and the maximum distance (screening distance) of a (QQbar)-pair in the hot plasma. All of them have been computed using the AdS/CFT correspondence. In order to discover a universal behaviour in the observables, computations have been worked out in the free gravity theory in AdS5 space-time which is dual to N=4 supersymmetric Yang–Mills theory as well as in three deformed, non-conformal metric models. Two of these are solutions to Einstein equations derived from a supergravity action. It has been shown that the energy loss of uniformly moving and of rotating quarks is very robust in all deformed models compared to the conformal results. In the case of the running coupling the introduction of deformations leads to a universal increase for larger (QQbar)-distances. This is qualitatively consistent with lattice QCD simulations. For the screening distance a proof has been presented for the conjecture that the conformal N=4T value for the screening distance is a lower bound for small perturbations around the conformal solution. Such a behaviour had been observed before in numerical studies in all of the above-mentioned deformed metric models

Porcine model elucidates function of p53 isoform in carcinogenesis and reveals novel circTP53 RNA

Recent years have seen an increasing number of genetically engineered pig models of human diseases including cancer. We previously generated pigs with a modified TP53 allele that carries a Cre-removable transcriptional stop signal in intron 1, and an oncogenic mutation TP53R167H (orthologous to human TP53R175H) in exon 5. Pigs with the unrecombined mutant allele (flTP53R167H) develop mainly osteosarcoma but also nephroblastomas and lymphomas. This observation suggested that TP53 gene dysfunction is itself the key initiator of bone tumorigenesis, but raises the question which aspects of the TP53 regulation lead to the development of such a narrow tumour spectrum. Molecular analysis of p53 revealed the presence of two internal TP53 promoters (Pint and P2) equivalent to those found in human. Consequently, both pig and human express TP53 isoforms. Data presented here strongly suggest that P2-driven expression of the mutant R167H-Δ152p53 isoform (equivalent to the human R175H-Δ160p53 isoform) and its circular counterpart circTP53 determine the tumour spectrum and play a critical role in the malignant transformation in flTP53R167H pigs. The detection of Δ152p53 isoform mRNA in serum is indicative of tumorigenesis. Furthermore, we showed a tissue-specific p53-dependent deregulation of the p63 and p73 isoforms in these tumours. This study highlights important species-specific differences in the transcriptional regulation of TP53. Considering the similarities of TP53 regulation between pig and human, these observations provide useful pointers for further investigation into isoform function including the novel circTP53 in both the pig model and human patients.ISSN:0950-9232ISSN:1476-559

Research and Design of a Routing Protocol in Large-Scale Wireless Sensor Networks

无线传感器网络，作为全球未来十大技术之一，集成了传感器技术、嵌入式计算技术、分布式信息处理和自组织网技术，可实时感知、采集、处理、传输网络分布区域内的各种信息数据，在军事国防、生物医疗、环境监测、抢险救灾、防恐反恐、危险区域远程控制等领域具有十分广阔的应用前景。 本文研究分析了无线传感器网络的已有路由协议，并针对大规模的无线传感器网络设计了一种树状路由协议，它根据节点地址信息来形成路由，从而简化了复杂繁冗的路由表查找和维护，节省了不必要的开销，提高了路由效率，实现了快速有效的数据传输。 为支持此路由协议本文提出了一种自适应动态地址分配算——ADAR（AdaptiveDynamicAddre...As one of the ten high technologies in the future, wireless sensor network, which is the integration of micro-sensors, embedded computing, modern network and Ad Hoc technologies, can apperceive, collect, process and transmit various information data within the region. It can be used in military defense, biomedical, environmental monitoring, disaster relief, counter-terrorism, remote control of haz...学位：工学硕士院系专业：信息科学与技术学院通信工程系_通信与信息系统学号：2332007115216