A generalization of Ore's Theorem involving neighborhood unions

AbstractLet G be a graph of order n. Settling conjectures of Chen and Jackson, we prove the following generalization of Ore's Theorem: If G is 2-connected and |N(u)∪N(v)|⩾12n for every pair of nonadjacent vertices u,v, then either G is hamiltonian, or G is the Petersen graph, or G belongs to one of three families of exceptional graphs of connectivity 2

Foreign Direct Investment in the United States: Interest Rate and Exchange Rate

David Y. Chen, Ph.D., is an associate professor, Department of Economics and Transportation/ Logistics. North Carolina A&T State University, Greensboro, NC 27411

TRANSLATING THE VISUAL: CHEN CHIEH-JEN’S WORK

Nacido en Taiwán y actualmente residente en Taipei, Chen Chieh-jen (1960) es un videoartista cuya obra presenta una profunda y feroz – aunque a menudo silenciosa – meditación histórica y política. Sus obras se caracterizan por la inserción de imágenes de archivo que se relacionan y dialogan con imágenes contemporáneas. Mirando el pasado de China en relación con su presente, Chen subraya las consecuencias sociales, las expectativas frustradas, las interpretaciones erróneas y las apropiaciones de la mirada occidental. En particular, este estudio aborda un vídeo realizado en 2002, “Lingchi - Echoes of a historical photograph” y otro, “Factory”, realizado en 2003 que revelan el foco principal y la praxis visual y auditiva del artista. En la obra de Chen, de hecho, la visión y, sobre todo, sus límites, tanto en el sentido concreto como en el metafórico, juegan un papel importante en la construcción de un denso discurso artístico y conceptual relacionado con la creación de imágenes y la traducción visual.Born in Taiwan and currently living in Taipei, Chen Chieh-jen (1960) is a video-artist whose oeuvre presents a profound and fierce – although often silent – historical and political meditation. His works are characterized by the insertion of archival footage in close dialogue with actual and contemporary images. Looking at China’s past in relation to its present, Chen underlines social damages, frustrated expectations, misinterpretations and appropriations by the Western gaze. In particular, this study addresses a video made in 2002, “Lingchi - Echoes of a historical photograph”, and “Factory” realized in 2003; having as a mainfocus the artist’s visual and aural praxis. In Chen’s work in fact, vision, and most of all its limits, in both a concrete and metaphorical sense, play a major part in the construction of a dense artistic and conceptual discourse related to image-making and visual translation.

Fractal atomic-level percolation in metallic glasses

Metallic glasses are metallic alloys that exhibit exotic material properties. They may have fractal structures at the atomic level, but a physical mechanism for their organization without ordering has not been identified. We demonstrated a crossover between fractal short-range (<2 atomic diameters) and homogeneous long-range structures using in situ x-ray diffraction, tomography, and molecular dynamics simulations. A specific class of fractal, the percolation cluster, explains the structural details for several metallic-glass compositions. We postulate that atoms percolate in the liquid phase and that the percolating cluster becomes rigid at the glass transition temperature

Caracterización de genes implicados en la biosíntesis de estreptolidigina

La estreptolidigina es un antibiótico perteneciente a la familia de los ácidos tetrámicos (Schobert y Schlenk, 2008) producido por Streptomyces lydicus. Estudios biosintéticos usando precursores marcados han demostrado la incorporación de propionato, acetato, metionina y ácido glutámico (probablemente en forma de metil-aspártico) en la formación de la estructura principal del antibiótico (Chen y Harrison, 2004; Chen et al., 2006). Estos estudios apuntan a un sistema híbrido policétido sintasa-sintetasa de péptidos no ribosomales para la biosíntesis de estreptolidigina, lo cual se ha confirmado con el reciente aislamiento y caracterización del agrupamiento génico responsable de la biosíntesis del antibiótico (Ola- no et al., 2009). Dentro de la ruta se han identificado genes encargados de la regulación y secreción del antibiótico y otros genes que codifican proteínas involucradas en el aporte y modificación final del precursor aminoacídico. En esta comunicación se presentan los experimentos de inactivación y expresión de los genes slgZ y slgM, para demostrar o comprobar su participación en la biosíntesis del antibiótico estreptolidigina

Mao Chen. Between tradition and change : the hermeneutics of May Fourth literature

This article reviews the book Between Tradition and Change: The Hermeneutics of May Fourth Literature , written by Mao Chen

A Macro Analysis of China Pension Pooling System: Incentive Issues and Financial Problem

Over a decade-long of pension reform in China has became much more critical in recent years. Problems of pension reform have started to reveal rapidly and pension reform pace has apparently slowed down. One sign of this is the decision made by the government to suspend a sell off of state-held shares in listed companies to fund the pension shortfall in October of 2001. The pension system built on 1995-reform platform has run into three major problems. First is a huge amount of unfunded pension liabilities inherited from the old system, and second is fragmentation of pension system has increased difficulty to finance pension liabilities. Third is a lack of a capital market to invest pension fund for a higher rate of return. These problems were rooted in the beginning of the pension reform and crippled effective operation of provincial pooling system over the years. And related resulting effects are rising pension deficit, accumulating notional individual accounts, increasing enterprise noncompliance and evasions, declining program participation, continuing financial burden of state-owned enterprises (SOEs) and a fast increase in SOEs retirements, and increasing weakness in central government fiscal conditions. This paper focuses on the incentive problems under the provincial pooling arrangement and aims to understand on a macro-level how adverse effects of the incapability of separation the new system from the old pension liabilities have complicated pension reform process and generated a series of unintended reform problems. The study uses aggregate data from national statistical sources and published data by domestic analysts to analyze incentive issues of state and nonstate sector in the pooling system. The paper answered the three questions. How did individual accounts become notional in the recent years? Why are there widespread noncompliance and evasions among state-owned enterprises toward pension contribution? Why is the non-state sector representing only a small share in provincial pooling pension program? The evidences indicate that current provincial pooling system is in a vicious cycle, financial problems are serious and public confidence in the system is low. Declining share of state sector and low share of non-state sector in contributing to pension program at local levels show that government's approach of expanding pension coverage to solve pension fund shortage at least in short term is ineffective. The government is facing a stark dilemma. Incapable of separating the old pension liability from the current pension financing system has led to an accumulation of unfunded individual accounts. The unfunded pension system and lack of capital accumulation of pension fund have shaken the confidence of current contributors of state enterprises and scares away new contributors from private and foreign invested enterprises. However, limited coverage, low program participation and widespread noncompliance and evasion reduce its pension revenue collection, increase financing gap and in fact double the difficulty to finance the liability, and that would further scare away new contributors too. Caught between the rock and a hard place, the government will have to figure out the approach and structure a reform path that follows pension reform sequencing. First to solve the old pension liabilities through pushing for financial capital market development or by ensuring some sort of central government responsibility. Second, to build the public confidence in the success of the pension system and gain the cooperation and willingness of pubic and private interest in the system. With that in mind, the pension reform outcomes will be both credible and financially viable.

Modeling of Packet Streaming Services in Information Communication Networks

Application of the term video streaming in contemporary usage denotes compression techniques and data buffering, which can transmit video in real time over the network. There is currently a rapid growth and development of technologies using wireless broadband technology as a transport, which is a seri- ous alternative to cellular communication systems. Adverse effect of the aggressive environment used in wireless networks transmission results in data packets undergoing serious distortions and often get- ting lost in transit. All existing research in this area investigate the known types of errors separately. At present there are no standard approaches to determining the effect of errors on transmission quality of services. Besides, the spate in popularity of multimedia applications has led to the need for optimization of bandwidth allocation and usage in telecommunication networks. Modern telecommunication networks should by their definition be able to maintain the quality of different applications with different Quality of Service (QoS) levels. QoS requirements are generally dependent on the parameters of network and application layers of the OSI model. At the application layer QoS depends on factors such as resolution, bit rate, frame rate, video type, audio codecs, and so on. At the network layer, distortions (such as delay, jitter, packet loss, etc.) are introduced