bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal efficiency at maximum work output: New results for old heat engines
Authors: Leff Harvey S.
Published: March 2005

What is the thermal efficiency of a heat engine producing the maximum possible work per cycle consistent with its operating-temperature range? This question is answered here for four model reversible heat engine cycles. In each case, the work is maximized with respect to two characteristic temperatures that are intermediate between the maximum and minimum cycle temperatures T+ and T−. The maximum-work efficiencies are found to equal or be well approximated by η*=1−(T−/T+)1/2. Because this efficiency is a function solely of the extreme cycle temperatures, it can be compared easily with the corresponding reversible Carnot cycle efficiency ηc =1−T−/T+. Here, η*, which is a much better guide to the performance of actual heat engines than ηc, is the same efficiency found by Curzon and Ahlborn [Am. J. Phys. 43, 22 (1975)] for a model irreversible heat engine operating at maximum power output. The present results show that η* is more ‘‘universal’’ than had been realized previously. If the work output per cycle is kept fixed, the thermal efficiency η of each cycle considered here can be increased by enlarging the heat engine and operating it at less-than-maximum work output per cycle. Formally, for such a fixed work output, η can approach the Carnot efficiency ηc in the limit of infinite engine size.
The black hole as a gravitational ‘‘lens’’
Authors: Ohanian Hans C.
Published: March 2005

We discuss the ‘‘images’’ formed when the light from a distant source suffers a large deflection in the intense gravitational field in the immediate vicinity of a Schwarzschild black hole. The light can circle around the black hole one or several times, and therefore give rise to a sequence of images. We show that the deflection angles and the intensities of the images can be expressed in terms of elliptic integrals, leading to simple approximations in the limiting case of very large deflection angles.
Modeling instruction in mechanics
Authors: Halloun Ibrahim Abou , Hestenes David
Published: March 2005

Modeling theory was used in the design of a method to teach problem solving in introductory mechanics. A pedagogical experiment to evaluate the effectiveness of the method found positive results.
Entropy in the teaching of introductory thermodynamics
Authors: Fuchs Hans U.
Published: March 2005

An elementary physics course on thermodynamics is presented. It uses entropy and temperature as fundamental, undefined objects. Suggestions on how to do this can be traced back to H. L. Callendar [Proc. Phys. Soc. (London) 23, 153 (1911)].
Sex-Specific Homeodomain Proteins Sxi1α and Sxi2
a
Coordinately Regulate Sexual Development in
Cryptococcus neoformans
Authors: Hull Christina M. , Boily Marie-Josee , Heitman Joseph
Published: March 2005

Homeodomain proteins are central regulators of development in eukaryotes. In fungi, homeodomain proteins have been shown to control cell identity and sexual development.
Cryptococcus neoformans
is a human fungal pathogen with a defined sexual cycle that produces spores, the suspected infectious particles. Previously, only a single homeodomain regulatory protein involved in sexual development, Sxi1α, had been identified. Here we present the discovery of Sxi2
a
, a predicted but heretofore elusive cell-type-specific homeodomain protein essential for the regulation of sexual development. Our studies reveal that Sxi2
a
is necessary for proper sexual development and sufficient to drive this development in otherwise haploid α cells. We further show that Sxi1α and Sxi2
a
interact with one another and impart similar expression patterns for two key mating genes. The discovery of Sxi2
a
and its relationship with Sxi1α leads to a new model for how the sexual cycle is controlled in
C. neoformans
, with implications for virulence.
Cellulase, Clostridia, and Ethanol
Authors: Demain Arnold L. , Newcomb Michael , Wu J. H. David
Published: March 2005

Biomass conversion to ethanol as a liquid fuel by the thermophilic and anaerobic clostridia offers a potential partial solution to the problem of the world's dependence on petroleum for energy. Coculture of a cellulolytic strain and a saccharolytic strain of
Clostridium
on agricultural resources, as well as on urban and industrial cellulosic wastes, is a promising approach to an alternate energy source from an economic viewpoint. This review discusses the need for such a process, the cellulases of clostridia, their presence in extracellular complexes or organelles (the cellulosomes), the binding of the cellulosomes to cellulose and to the cell surface, cellulase genetics, regulation of their synthesis, cocultures, ethanol tolerance, and metabolic pathway engineering for maximizing ethanol yield.
Stiffness of Capacitive and Conduit Arteries
Authors: Pannier Bruno , Guérin Alain P. , Marchais Sylvain J. , Safar Michel E. , London Gérard M.
Published: March 2005

The aorta is the principal capacitive element of the arterial tree and its increased stiffness, determined by measurement of aortic pulse wave velocity (PWV), is a strong independent predictor of cardiovascular mortality in the general population and end-stage renal disease (ESRD) patients. Whether stiffness of ESRD patients’ peripheral arteries has the same prognostic value has never been investigated. A cohort of 305 ESRD patients was followed for 70±49 months (mean±SD). Ninety-six deaths of cardiovascular origin occurred. At entry into the study, together with standard clinical and biochemical analyses, patients’ aortic, brachial artery, and femorotibial PWV were determined. Based on Kaplan–Meier survival curve analyses and Cox proportional hazards analyses, adjusted for age, pulse pressure, and clinical data, aortic PWV was a significant and independent predictor of outcome. Neither brachial artery nor femotibial artery stiffness was able to predict cardiovascular outcome. Receiver operating characteristic curve analysis of aortic PWV indicated the cutoff value of 10.75 m/s, with 84% sensitivity, 73% specificity, 87% negative predictive value, and 72% positive predictive value. These results provide evidence that, in ESRD, increased stiffness of capacitive arteries, like the aorta, is an independent strong predictor of cardiovascular mortality, whereas stiffness of peripheral conduit arteries had no prognostic value.
Chinese Nationalism and the 2001 US Spy Plane Incident
Authors: Zhang Yu
Published: March 2005

Barely six months before the September 2001 terrorist attacks against the United States, a major incident threatened to bring the volatile relationship between China and the United States to crisis point. An American military plane along with its crew was seized by China for violating its air space and spying. Despite dignified denouement through diplomatic channels, the manner in which China viewed and handled issues thrown up by the incident has been attributed widely and mistakenly to China’s political leadership without factoring the growth of Chinese nationalism as a determinant of China’s US policy. However, the incident would have been handled more meaningfully if the two countries had communicated better with each other.
Yanadi kinship terminology and the expression of affinity
Authors: Rao N. Sudhakar
Published: March 2005

Distinctive in its content and nature, Dravidian kinship has been the object of considerable interest and debate among social anthropologists and sociologists studying South Asian social systems. This article examines the kinship terminology of one of the Dravidian communities, the Yanadi, inhabiting the Sriharikota island, Andhra Pradesh, India. In this endeavour, some of the theoretical issues concerning Dravidian kinship are reflected upon and attempts are made to resolve some issues in the light of the Yanadi data. It is argued that the native classification of kinsmen and the cultural construction of affinal relatives reflect a close association of the kinship terminology with cross-cousin marriage and affinity. The article underlines the importance of a cultural analysis of kinship to supplement the formal and widely-employed structural analysis of kinship terminologies.
Chaos and the Dancing Stars
Authors: Johnes Geraint , Kalinoglou Alexander , Manasova Ayana
Published: March 2005

The determinants of the decision to become self-employed are analysed in a logit model which includes as arguments a variety of economic, psychological and environmental perspectives. Of particular interest is the role played by workers’ abilities to predict chaotic patterns in data. Chaos was operationalised as a set of observations of variables drawn at different points of time, wherein the relationship between the values taken by the variables in one period was determined precisely by the values they had taken in the past according to a non-linear relationship. The plausibility of individuals more sensitive than others to chaos being more successful than others in initiation and leadership functions— which are characteristics of entrepreneurs— was examined through a binomial logit exercise that required individuals to forecast daily equity prices. Whether the ability to forecast complex time series is a distinguishing trait of entrepreneurs received robust support in relation to some demographic and psychographic variables, and weak support in relation to others.
Affliction and Testimony
Authors: Addlakha Renu
Published: March 2005

This paper is an attempt to map out the life-world of a young unmarried woman with a diagnosis of schizophrenia, whom the author met in the course of her ethnographic study of general hospital psychiatry in a Delhi public hospital (Addlakha 1999). It is primarily based on the author’s reading of Parvati Devi’s diary, a document meticulously maintained by the patient in the months prior to her hospitalisation at the Lady Hardinge Hospital, New Delhi. Using the concepts of testimony, experience, narrative and voice, the paper explores a range of issues that appear to be germane to the constitution of a life-world, precariously pitched on the shifting sands of the real, the possible and the unimaginable. Methodologically, the reading of the diary is juxtaposed with an analysis of the patient’s case record and interactions with her and her family in the ward and home spaces. The positionality of the author as a single woman with visual impairment of approximately the same age cohort, social location within the urban nuclear family and cultural milieu brings a critical reflexivity to the research.
Exploring the Frontiers of Environmental Management: A Natural Law-based Perspective
Authors: Steingard David S. , Fitzgibbons Dale E. , Heaton Dennis
Published: March 2005

Environmental management (EM) is at a turning point in its evolution as a discipline. Daunting social, ecological and spiritual problems of global magnitude implore EM to be inspiring and efficacious in theory and practice. Ironically, the present EM movement, in its ontologically dualistic configuration—measuring and manipulating the environment as an abstract, objectified economic resource for human gain—is unknowingly contributing to the very ecological degradation it wishes to ameliorate. In order for EM to become a truly ‘transformative epistemology’,1its praxis must ontologically transcend the narrow foundations of staunch empiricism, logical positivism and rationalism that now firmly gird it. As a possible alternative to EM’s ‘monological flatland’,2we introduce a holistic praxiological system grounded in the ancient Indian vedanta wisdom tradition. Natural law-based environmental management (NLBEM) portends a radical metamorphosis of EM into a discipline that makes a meaningful impact on today’s precarious global condition.
Towards Knowing Ourselves: Classical Yoga Perspective
Authors: Jakubczak Marzenna
Published: March 2005

Self-knowledge, at first glance, seems to be naturally and easily accessible to each of us. We commonly believe that we need much less effort to understand ourselves than to understand the world. In this article, the author uncovers the fallacy of this popular view referring to the fundamental conceptions and philosophical ideas of the classical yoga. She tries to demystify our deceptive self-understanding explaining the definitions of ignorance (avidya) , I-am-ness (asmita) , desire (raga) , aversion (dvesha) and fear of death (abhinivesha) following the oldest yoga treatise. The article then goes on to discuss briefly how we can make use of our limited, incorrect self-knowledge as far as we are aware that it needs to be transcended. In the final part of the article, the issue of self-discipline consisting basically in cultivation of detachment and the practice of meditation is addressed.
A History of Bayana Part 1: From the Muslim Conquest to the End of the Tughluq Period
Authors: Shokoohy Mehrdad , Shokoohy Natalie H.
Published: March 2005

For the sultans of Delhi control of Bayana in eastern Rajasthan was a key to securing their southern territories from the local Hindu rajas. The first part of the study here sets out the history from inscriptions, standing monuments, and contemporary texts. It looks beyond the fort and town and establishes the boundaries of the region, its resources and the ethnic origin of its Muslim population. The second part is planned to present the history from the time of Tīmūr’s invasion, and will deal with the rise of the autonomous local Auadī rulers, and the role of Bayana under the Lodīs, Sūrīs and early Mughals, and its eventual decline after the foundation of Agra, formerly one of its villages.
Occupational Stress of Women in Small-scale Industry
Authors: Desai Riti , Gaur Ray
Published: March 2005

This study examines the work posture of women workers (experimental group) engaged in small-scale industries who have to maintain a constant seated position (squatting cross-legged) on the floor. Along with the worker group, an equal number of housewives belonging to the same socio-economic status were also studied as a control group. The latter group never maintained such kinds of posture for prolonged periods. To ascertain the effect of work posture, qualitative and quantitative assessment procedures were followed for both groups, in the field and in laboratory studies. It was observed that there was a significant difference in body pain and discomfort among the experimental and control groups, which can be attributed to the prolonged sitting postures. The results of various other assessment procedures were considered and recommendations for suitably designed workstations were given.
Occupational Female Reproductive Hazards
Authors: Jadav Swati D.
Published: March 2005

The survival of a species depends on the integrity of its reproductive system. Damage by physical or chemical agents to the sperm, ovum or fertilised ovum may cause infertility, spontaneous abortion and birth defects, or may result in mutations that are passed on to future generations. When considering occupational exposures that may damage reproductive processes, the hazard to both men and women must be examined. Disorders of reproduction and hazards to reproductive health have become prominent public health issues now. Rubella (German measles) was recognised as a major cause of birth defects in the 1940s. In the 1960s the use of thalidomide sensitised the public to chemically induced birth defects. Early in the 1970s young women whose mothers had taken diethylstilbestrol during pregnancy were found to have vaginal problems. Later in the decade, it was discovered that men occupationally exposed to dibromochloropropane (DBCP) were subject to varying degrees of testicular toxicity, potentially culminating in infertility. More than 100 years ago, lead was discovered to cause miscarriages, stillbirths and infertility in female pottery workers. These have heightened sensitivities to potential occupational, therapeutic or environmental hazards to reproduction.
How Important are Foreign Banks in the Financial Development of European Transition Countries?
Authors: Naaborg Ilko , Scholtens Bert , de Haan Jakob , Bol Hanneke , de Haas Ralph
Published: March 2005

This article analyses the development of the banking sector in European transition countries. We find that, although bank assets increased during the 1990s, credit to the private sector remained relatively low. Foreign-owned banks have become major players in the financial system of these countries. However, foreign bank presence and financial development in general vary considerably among the transition economies. Foreign-owned banks have, in general, higher profitability levels than domestic banks. Furthermore, it appears that foreign and domestic bank performance tend to converge.
Historical Impacts on Political Economy in Pakistan
Authors: Ali Imran
Published: March 2005

This article analyses the role and impact of the pre-1947 historical developments on political, policy and economic configurations in post-1947 Pakistan. There is a major gap in social science analysis on how and why these processes had pre-1947 main-springs. The article illustrates that Pakistan experienced a substantial level of resilience and continuity of structures and processes from the period of British rule and even earlier. This ‘long view’ can help us understand the undercurrents and articulations of power in the state of Pakistan.

The article scrutinizes transitions in the late Mughal period; British policies and their consequences; and the major political transitions and policy parameters in post-1947 Pakistan. Linkages and continuities, as well as the relationships between the past and present, are brought together in this article in an effort to understand the fundamental forces that have shaped the political economy of Pakistan.
Indian Foundries Limited
Authors: Pandey Rahul , Srivastava Rajiv K. , Srivastava Samir
Published: March 2005

This case details the working of Indian Foundries Limited, a company which has been in business for 32 years. It has been producing a large volume and variety of high quality foundry products, mainly for export markets. Of late, however, the company has been facing problems of high lead times, excess inventory stocks and in-process quality defects. These problems have come at a particularly bad time when Indian Foundries is facing stiff competition from Chinese exporters. For Indian Foundries the need is for a quick fix of their problems: otherwise they are likely to lose their core customer base to the Chinese.
Performance Engineering Technology for the Design, Management, and Control of Computing Systems
Authors: Darema Frederica
Published: March 2005

This paper discusses a systematic new methodology for analyzing and predicting the performance of computing systems. The approaches considered address analysis of the computing system viewed in terms of an architectural framework consisting of the applications, the system software, and the underlying hardware. The methodology discussed enables analysis of the interdependent effects of these layers to the behavior of the system. To enable that, the layers and components of the system are described in multiple levels of detail and in multiple modes (analytical and simulation approaches as well as integrated performance measurements). Key approaches will be the ability to use these multilevel and multimodal methods of describing such systems and their subcomponents and incorporate them into performance frameworks in a plug-and-play fashion, to enable the capability to describe system behavior. In addition, it is envisioned that this technology will not only support the design of the complex systems but also be used in the runtime (control) and management cycles of these systems. These new methods will allow the design of individual components and also provide capabilities for system analysis and design, as well as provide a path from understanding component behavior to understanding system behavior and from understanding component behavior to predicting system behavior. The term performance engineering technology is used here to describe the technology that supports the capabilities discussed here.
A Portable Programming Interface for Performance Evaluation on Modern Processors
Authors: Browne S. , Dongarra J. , Garner N. , Ho G. , Mucci P.
Published: March 2005

The purpose of the PAPI project is to specify a standard application programming interface (API) for accessing hardware performance counters available on most modern microprocessors. These counters exist as a small set of registers that count events, which are occurrences of specific signals and states related to the processor’s function. Monitoring these events facilitates correlation between the structure of source/object code and the efficiency of the mapping of that code to the underlying architecture. This correlation has a variety of uses in performance analysis, including hand tuning, compiler optimization, debugging, benchmarking, monitoring, and performance modeling. In addition, it is hoped that this information will prove useful in the development of new compilation technology as well as in steering architectural development toward alleviating commonly occurring bottlenecks in high performance computing.
The Development of Parkbench and Performance Prediction
Authors: Hey Tony , Lancaster David
Published: March 2005

The authors present a brief overview of the development of benchmarks for parallel performance analysis and show how a set of widely accepted parallel benchmarks has emerged from the Parkbench initiative. At the lowest level, basic node parameters are captured by the LINPACK benchmark and the Genesis communications benchmarks, which give information on message-passing latency and bandwidth. At kernel and application levels, results are widely available for the NAS parallel benchmarks. A new release of the Genesis communications benchmarks is described, which addresses the important issue of the effect of memory hierarchy on message transfers. The rest of the paper is concerned with the way in which benchmark results can be used to predict performance of full applications. Three studies are considered: the PERFORM estimation tool and WHITEBOX benchmarking are research projects, indicating some possible directions for progress, while INTREPID is the basis of a commercial system for scheduling meta-applications based on performance models for the components.
Performance Evaluation Model for Scheduling in Global Computing Systems
Authors: Aida Kento , Takefusa Atsuko , Nakada Hidemoto , Matsuoka Satoshi , Sekiguchi Satoshi , Nagashima Umpei
Published: March 2005

Striking progress of network technology is enabling high performance global computing, in which computational and data resources in a wide-area network (WAN) are transparently employed to solve large-scale problems. Several high performance global computing systems, such as Ninf, NetSolve, RCS, Legion, and Globus, have already been proposed. Each of these systems proposes to effectively achieve high performance with some efficient scheduling scheme, whereby a scheduler selects a set of appropriate computing resources that solve the client’s computational problem. This paper proposes a performance evaluation model for effective scheduling in global computing systems. The proposed model represents a global computing system by a queuing network, in which servers and networks are represented by queuing systems. Verification of the proposed model and evaluation of scheduling schemes on the model showed that the model could simulate behavior of an actual global computing system and scheduling on the system effectively.
Compositional Development of Performance Models in Poems
Authors: Browne J. C. , Berger E. , Dube A.
Published: March 2005

Performance models are software systems in which the components implement abstractions of the behavior of a total system. This paper describes a capability for semiautomatic development of performance models of computer systems spanning applications, operating systems, and hardware by composition from a library of components. Compositional development of performance models is a domain-specific instance of the general problem of software component reuse or design reuse. The concepts enabling compositional development of performance models in POEMS are encapsulation of analysis-level objects with associative interfaces and hierarchical dynamic data flow graphs as a structuring model. Objects with associative interfaces will be called compositional objects. Compositional objects and hierarchical dynamic data flow graphs provide a framework for the development of performance models that incorporate multiple modes of evaluation, span multiple semantic domains, span multiple levels of abstraction, and parallel implementation. Algorithms for composition through associative interfaces with automatic generation of parallel executables for the performance models will be defined.
Reconfiguration of Complete Binary Trees in Full IEH Graphs and Faulty Hypercubes
Authors: Lin Jen-Chih , Keh Huan-Chao
Published: March 2005

The incrementally extensible hypercube (IEH) graph is a generalization of binary hypercube networks in that the number of nodes can be arbitrary in contrast to a strict power of 2. In this paper, the authors present an efficient model to fulfill the embedding of a full binary tree into a full IEH graph. As the model the authors proposed, an algorithm is developed for the embedding with expansion 1, load 1, congestion 2, and dilation 2. Moreover, the embedding algorithm can be also applied into hypercubes with one faulty node.
Distributing MCell Simulations on the Grid
Authors: Casanova Henri , Bartol Thomas M. , Stiles Joel , Berman Francine
Published: March 2005

The computational Grid is a promising platform for the deployment of large-scale scientific and engineering applications. Parameter sweep applications (PSAs) arise in many fields of science and engineering and are structured as sets of “experiments,” each of which is executed with a distinct set of parameters. Given that structure, PSAs are particularly well suited to the Grid infrastructure and can be deployed on very large scales. However, deployment is not easy to achieve for the domain scientist given the complexity and multiplicity of the Grid software infrastructure, the heterogeneity of the resources, and the dynamic resource availabilities. It is therefore necessary to provide user-level middleware that acts as an intermediate layer between the application and the Grid. That middleware must address all deployment, data movements, and scheduling issues to provide the user with a transparent way of running his or her simulation on the Grid. In this paper, the authors focus on such middleware specifically targeted to a biology application: MCell. After describing the application and its structure, they describe desired usage scenarios on the Grid and identify user requirements, discuss relevant computer science issues, and propose suitable solutions given currently available Grid technologies. The authors then describe a general-purpose user-level middleware project for PSAs—AppLes Parameter Sweep Template—explain how it can be extended to accommodate MCell’s specific requirements, and introduce current work in that direction.
Performance Predictions for a Numerical Relativity Package in Grid Environments
Authors: Ripeanu Matei , Iamnitchi Adriana , Foster Ian
Published: March 2005

The Cactus software package is representative for a class of scientific applications that are tightly coupled, have regular space decompositions, and involve huge memory and processor time requirements. Cactus has proved to be a valuable tool for astrophysicists, who first initiated its development. However, today’s fastest supercomputers are not powerful enough to perform realistic large-scale astrophysics simulations with Cactus. Instead, astrophysicists must turn to innovative resource environments—in particular, computational grids—to satisfy this need for computational power. This paper addresses issues related to the execution of applications such as Cactus in grid environments. The authors focus on two types of grids: a set of geographically distributed supercomputers and a collection of one million Internet-connected workstations. The authors study the application performance on traditional systems, validate the theoretical results against experimental data, and predict performance in the two new environments.
Investigation of Large Eddy Simulation Code Scaling Performance and Network Type Influence on a Linux PC Cluster
Authors: Chernyavsky Boris , Knight Doyle
Published: March 2005

The parallel performance of a large eddy simulation computational fluid dynamics code was evaluated on a Pentium III PC cluster with 64 processors running under Linux. Scaling capability of the code and comparative code performance under Fast Ethernet, Myrinet, and Gigabit Ethernet were investigated. The code shows very good scalability for a scaled speedup test with wall clock time remaining practically constant for any number of processors. The code does not saturate the Fast Ethernet bandwidth. Whereas Myrinet demonstrates a lower difference between CPU and wall clock time, indicating more efficient interprocessor communication, its overall wall clock time is equal to or higher than for the code compiled for Fast Ethernet. Gigabit Ethernet shows a very slight advantage over Fast Ethernet.
High Performance Computing in Multibody System Design
Authors: Baldini Sandra , Giraud Luc , Izaguirre Javier G. , Jimenez Jose M. , Matey Luis M.
Published: March 2005

This paper presents recent developments of high performance computing and networking techniques in the field of computer-aided multibody analysis and design. The authors describe the main achievements obtained in the development of a tool to aid in the design of new industrial mechanical systems by performing parallel parametric multibody simulations. The parallel software is composed of four main modules: two user-friendly interfaces to input the data and visualize the results, a simulation module, and a parallel manager module that is the main focus of this paper. The authors show that the implementation, using PVM, of simple and well-known ideas leads to efficient and flexible parallel software targeted for heterogeneous networks of nondedicated workstations, which is the parallel platform available in most mechanical design departments. The authors also describe the main features of this module that implements, for the sake of efficiency and robustness, a load-balancing strategy and fault tolerance capabilities. One of the main results of this development has been to demonstrate that high performance computing can sometimes be easily and efficiently introduced into industrial companies without requiring major investments. Pictures of the user interfaces are depicted to illustrate the usability of the parallel software. Performance observed on single and multiprocessor workstation networks is given to assess the relevance of using high performance computing techniques in an industrial environment for the design of mechanical systems.
A Rigid-Body-Based Multiple Time Scale Molecular Dynamics Simulation of Nanophase Materials
Authors: Nakano Aiichiro
Published: March 2005

Nanophase technology achieves superior material properties by assembling nanometer-size clusters. Structures on multiple-length scales and a hierarchy of time scales are essential for the design and control of nanophase materials. However, coexistence of a wide range of length and time scales hinders atomistic simulations of these materials. A new algorithm is developed for large-scale, longtime molecular dynamics simulations by combining (1) quaternion-based, rigid-body dynamics for global cluster motions; (2) implicit integration of Newton’s equations for the coalescence of clusters; and (3) normal-mode analysis of fast atomic oscillations. The new scheme, using a time step Δt of 10-12 seconds, speeds up a conventional explicit integration scheme (Δt=2 × 10-15 seconds) by a factor of 28. A parallel implementation of the scheme achieves an efficiency of 0.94 for a 1.28-million-atom nanocrystalline silicon nitride solid on 64 nodes of an IBM SP computer.
Improving Goodput by Coscheduling CPU and Network Capacity
Authors: Basney Jim , Livny Miron
Published: March 2005

In a cluster computing environment, executable, checkpoint, and data files must be transferred between application submission and execution sites. As the memory footprint of cluster applications increases, saving and restoring the state of a computation in such an environment may require substantial network resources at both the start and the end of a CPU allocation. During the allocation, the application may also consume network bandwidth to periodically transfer a checkpoint back to the submission site or checkpoint server and to access remote data files. Under most circumstances, the application cannot use the allocated CPU while these transfers are in progress. Furthermore, if the application is unable to transfer a checkpoint or successfully migrate at preemption time, work already accomplished by the application is lost. The authors define goodputas the allocation time when a remotely executing application uses the CPU to make forward progress. Goodput can be significantly less than allocated throughput due to network activity. The authors are currently engaged in an effort to develop coscheduling techniques for CPU and network resources that will improve the goodput delivered by Condor pools. They report techniques that they have developed so far, how they were implemented in Condor, and their preliminary impact on the goodput of the authors’ production Condor pool.
Using Dynamic Kernel Instrumentation for Kernel and Application Tuning
Authors: Tamches Ariel , Miller Barton P.
Published: March 2005

The authors have designed a new technology—fine-grained dynamic instrumentation of commodity operating system kernels—that can insert runtime-generated code at almost any machine code instruction of an unmodified operating system kernel. This technology is ideally suited for kernel performance profiling, debugging, code coverage, runtime optimization, and extensibility. They have written a tool called KernInst that implements dynamic instrumentation on a stock production Solaris 2.5.1 kernel running on an UltraSparc CPU. They have written a kernel performance profiler on top of KernInst. Measuring kernel performance has a two-way benefit: it can suggest optimizations to both the kernel and applications that spend much of their time in kernel code. In this paper, the authors present their experiences using KernInst to identify kernel bottlenecks when running a Web proxy server. By profiling kernel routines, they were able to understand performance bottlenecks inherent in the proxy’s disk cache organization. The authors used this understanding to make two changes—one to the kernel and one to the application—that cumulatively reduce the percentage of elapsed time that the proxy spends opening disk cache files for writing from 40% to 7%.
Toward Scalable Performance Visualization with Jumpshot
Authors: Zaki Omer , Lusk Ewing , Gropp William , Swider Deborah
Published: March 2005

Jumpshot is a graphical tool for understanding the performance of parallel programs. It is in the tradition of the upshot tool but contains a number of extensions and enhancements that make it suitable for large-scale parallel computations. Jumpshot takes as input a new, more flexible logfile format and comes with a library for generating such logfiles. An MPI profiling library is also included, enabling the automatic generation of such logfiles from MPI programs. Jumpshot is written in Java and can easily be integrated as an applet into browser-based computing environments. The most novel feature of Jumpshot is its automatic detection of anomalous durations, drawing the user’s attention to problem areas in a parallel execution. This capability is particularly useful in large-scale parallel computations containing many events.
Liberalization Measures in India’s Coffee Sector: Analytical Implications for Market Structure and Consumer Welfare Analyses in Developing Countries
Authors: Narayana M. R.
Published: March 2005

This article develops a simple economic model to explain the observed market structure, nature of production and behaviour of coffee consumers before 1993, and analyses these changes, since 1993, as a consequence of liberalization and globalization measures. Market equilibrium conditions under controlled (and free) domestic and export trade during pre- (and post-) liberalization period are derived and analyzed. For a comparison of the welfare levels between the equilibria, an applied welfare economic framework is suggested. An empirical implementation of this framework will resolve current policy debates, such as ( a) continuation of liberalization and globalization measures in the coffee sector and ( b) it will test whether or not the consensus in favour of new orthodoxy of economic liberalization and globalization in the coffee sector is sound on both theoretical and empirical grounds. The results of this article are of relevance for other coffee-producing, developing countries for two reasons. First, if liberalization and globalization measures in their coffee sectors are yet to be started, India’s experience may serve as a useful guideline. Second, if liberalization and globalization measures are under implementation in their coffee sector, the welfare framework in this article may be helpful to undertake policy useful impact analysis.
Biosocial Development and Delinquent Involvement
Authors: Beaver Kevin M. , Wright John Paul
Published: March 2005

In this article, we examine the influence of pubertal development on misbehavior, as well as examine a series of Gene × Environment Interactions. Specifically, we examine whether the onset of puberty interacts with preexisting temperamental differences and whether puberty influences peer groups selection. The data for this study come from the public-use version of the National Longitudinal Study of Adolescent Health, a nationally representative sample of 6,504 adolescents. The results show that pubertal development is a robust predictor of misbehavior (especially for boys) and that puberty interacts with individual differences and with peer group affiliation.
Phase I/II Trial Evaluating the Anti-Vascular Endothelial Growth Factor Monoclonal Antibody Bevacizumab in Combination With the HER-1/Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor Erlotinib for Patients With Recurrent Non–Small-Cell Lung Cancer
Authors: Herbst Roy S. , Johnson David H. , Mininberg Eric , Carbone David P. , Henderson Ted , Kim Edward S. , Blumenschein George , Lee Jack J. , Liu Diane D. , Truong Mylene T. , Hong Waun K. , Tran Hai , Tsao Anne , Xie Dong , Ramies David A. , Mass Robert , Seshagiri Somasekar , Eberhard David A. , Kelley Sean K. , Sandler Alan
Published: March 2005

Purpose

Bevacizumab (Avastin; Genentech, South San Francisco, CA) is a recombinant, humanized anti-vascular endothelial growth factor monoclonal antibody. Erlotinib HCl (Tarceva, OSI-774; OSI Pharmaceuticals, New York, NY) is a potent, reversible, highly selective and orally available HER-1/epidermal growth factor receptor tyrosine kinase inhibitor. Preclinical data in various xenograft models produced greater growth inhibition than with either agent alone. Additionally, both agents have demonstrated benefit in patients with previously treated non–small-cell lung cancer (NSCLC).

Patients and Methods

A phase I/II study in two centers examined erlotinib and bevacizumab (A+T) in patients with nonsquamous stage IIIB/IV NSCLC with ≥ one prior chemotherapy. In phase I, erlotinib 150 mg/day orally plus bevacizumab 15 mg/kg intravenously every 21 days was established as the phase II dose, although no dose-limiting toxicities were observed. Phase II assessed the efficacy and tolerability of A+T at this dose. Pharmacokinetic parameters were evaluated.

Results

Forty patients were enrolled and treated in this study (34 patients at phase II dose); the median age was 59 years (range, 36 to 72 years), 21 were female, 30 had adenocarcinoma histology, nine were never-smokers, and 22 had ≥ two prior regimens (three patients had ≥ four prior regimens). The most common adverse events were mild to moderate rash, diarrhea, and proteinuria. Preliminary data showed no pharmacokinetic interaction between A+T. Eight patients (20.0%; 95% CI, 7.6% to 32.4%) had partial responses and 26 (65.0%; 95% CI, 50.2% to 79.8%) had stable disease as their best response. The median overall survival for the 34 patients treated at the phase II dose was 12.6 months, with progression-free survival of 6.2 months.

Conclusion

Encouraging antitumor activity and safety of A+T support further development of this combination for patients with advanced NSCLC and other solid tumors.
Visual cues eliciting the feeding reaction of a planktivorous fish swimming in a current
Authors: Mussi Martina , McFarland William N. , Domenici Paolo
Published: March 2005

The visual plankivorous feeding behaviour of the shiner perch(Cymatogaster aggregata) was investigated by means of a flow tank operated at various current speeds. Artemia salina was used as prey. In a second set of experiments, Artemia was darkened with black ink,to compare the visually mediated behaviour of C. aggregata while feeding on dark prey vs feeding on natural (i.e. semi-transparent)prey. The positions of the fish and its prey at the time of the feeding reaction of C. aggregata were measured in three dimensions. Prey were on average closer and more in line with the fish's axis when feeding reactions to darkened Artemia were considered, in comparison with natural Artemia. Three potential mechanisms triggering the feeding reaction of C. aggregata were explored: the prey may trigger a reaction in C. aggregata when it reaches a threshold (1) angular size, (2)angular velocity, or (3) rate of change of the angular size (i.e. loom) of the prey as it is carried passively by the current towards the fish. Our results show that angular velocity may trigger the fish's reaction when using semi-transparent prey, while loom may trigger the reaction to darkened prey. This suggests that feeding behaviour of planktivorous fish is flexible and can use different cues to trigger a motor reaction to prey with different visual characteristics. The feeding reaction appeared to occur at longer distances for semi-transparent rather than darkened Artemia. We suggest that semi-transparent Artemia were visible at greater distances because of their higher scattering (i.e. diffuse reflectance) that made them appear brighter when viewed against a dark background.
Distribution of methanol and catalysts between biodiesel and glycerin phases
Authors: Chiu Chuang‐Wei , Goff Michael J. , Suppes Galen J.
Published: March 2005

When transesterifying alcohols with fats and oils to produce biodiesel, the phase behavior and respective distribution of catalyst and alcohol between liquid phases can significantly impact both reaction rates and product workup. To better understand this phase behavior, the distribution of methanol and catalysts, potassium hydroxide and sulfuric acid, between the biodiesel and alcohol phases was experimentally investigated and modeled. Experimental vapor‐liquid equilibrium data were modeled by using the Wilson activity coefficient model and two temperature‐independent model parameters are used to obtain good agreement between calculated and experimental data. The distribution coefficients of methanol between biodiesel and glycerin phases were accurately predicted by the VLE activity coefficients and Wilson model. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Hypercoordinated organotin triflates
Authors: Beckmann Jens
Published: March 2005

Recent advances in the chemistry of organotin triflates and related organotin cations are reviewed. Applications in synthesis and catalysis are briefly discussed. Copyright © 2005 John Wiley & Sons, Ltd.
Field‐effect transistor based on organosoluble germanium nanoclusters
Authors: Watanabe Akira , Hojo Fusao , Miwa Takao
Published: March 2005

The structural and electrical properties of organosoluble germanium nanoclusters are studied. The organogermanium nanocluster (OGE) is a polygermane with a three‐dimensional σ‐conjugated chain. The OGE is prepared from GeCl4 by a simple one‐pot reaction, where the germanium nanocluster is obtained by the reaction of GeCl4 using magnesium metal and the capping reaction of the chlorine group by an alkyl Grignard reagent in tetrahydrofuran. The optical energy gap of the tert‐butyl‐substituted OGE is lower than that of the n‐propyl‐substituted OGE, corresponding to the higher molecular weight and the larger extent of the σ‐conjugation along the GeGe chain. The conductivity of the OGE is enhanced by heat treatment, which induces the elimination of organic substituents, the reconstruction of the GeGe chain, and the extension of a three‐dimensional germanium network among germanium clusters. The field‐effect transistor fabricated by a coating technique using the tert‐butyl‐substituted OGE shows signal amplification properties. Copyright © 2005 John Wiley & Sons, Ltd.
Resistance of insect pests to neonicotinoid insecticides: Current status and future prospects
Authors: Nauen Ralf , Denholm Ian
Published: March 2005

The first neonicotinoid insecticide introduced to the market was imidacloprid in 1991 followed by several others belonging to the same chemical class and with the same mode of action. The development of neonicotinoid insecticides has provided growers with invaluable new tools for managing some of the world's most destructive crop pests, primarily those of the order Hemiptera (aphids, whiteflies, and planthoppers) and Coleoptera (beetles), including species with a long history of resistance to earlier‐used products. To date, neonicotinoids have proved relatively resilient to the development of resistance, especially when considering aphids such as Myzus persicae and Phorodon humuli. Although the susceptibility of M. persicae may vary up to 20‐fold between populations, this does not appear to compromise the field performance of neonicotinoids. Stronger resistance has been confirmed in some populations of the whitefly, Bemisia tabaci, and the Colorado potato beetle, Leptinotarsa decemlineata. Resistance in B‐ and Q‐type B. tabaci appears to be linked to enhanced oxidative detoxification of neonicotinoids due to overexpression of monooxygenases. No evidence for target‐site resistance has been found in whiteflies, whereas the possibility of target‐site resistance in L. decemlineata is being investigated further. Strategies to combat neonicotinoid resistance must take account of the cross‐resistance characteristics of these mechanisms, the ecology of target pests on different host plants, and the implications of increasing diversification of the neonicotinoid market due to a continuing introduction of new molecules. Arch. Insect Biochem. Physiol. 58:200–215, 2005. © 2005 Wiley‐Liss, Inc.
Quantitative Transduction of Excited‐State Energy inFluorophore‐Heterofullerene Conjugates
Authors: Hauke Frank , Hirsch Andreas , Atalick Stefan , Guldi Dirk
Published: March 2005

A novel series of fluorophore‐heterofullerene conjugates 10–14 — the fluorophores range from benzene, naphthalene, phenanthrene, and fluorene to pyrene — was synthesized. NMR spectroscopy and quantum mechanical calculations demonstrate that the flexibility of the acetyl‐group linker opens the way for conformations with π–π stacking interactions between the chromophores. This leads to favorable electronic communication between the two subsystems and is reflected in a series of ground‐ and excited‐state assays ranging from fluorescence to fast transient absorption measurements. It was found that a common deactivation process of the photoexcited fluorophores takes place, namely, a quanti‐tative transduction of singlet excited state, yielding the hetero‐fullerene singlet excited state. This reaction pathway leads to the long‐lived and highly reactive fullerene triplet state, which forms, in a reaction with molecular oxygen, a cytotoxic oxygen species (i.e. singlet oxygen). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)