bluuebunny/crossref_metadata_2025 huggingface dataset:
Sequence Analysis of the Genome of the
Neodiprion sertifer
Nucleopolyhedrovirus
Authors: Garcia-Maruniak Alejandra , Maruniak James E. , Zanotto Paolo M. A. , Doumbouya Aissa E. , Liu Jaw-Ching , Merritt Thomas M. , Lanoie Jennifer S.
Published: June 2004

The genome of the
Neodiprion sertifer
nucleopolyhedrovirus (NeseNPV), which infects the European pine sawfly,
N. sertifer
(Hymenoptera: Diprionidae), was sequenced and analyzed. The genome was 86,462 bp in size. The C+G content of 34% was lower than that of the majority of baculoviruses. A total of 90 methionine-initiated open reading frames (ORFs) with more than 50 amino acids and minimal overlapping were found. From those, 43 ORFs were homologous to other baculovirus ORFs, and 29 of these were from the 30 conserved core genes among all baculoviruses. A NeseNPV homolog to the
ld130
gene, which is present in all other baculovirus genomes sequenced to date, could not be identified. Six NeseNPV ORFs were similar to non-baculovirus-related genes, one of which was a trypsin-like gene. Only one
iap
gene, containing a single BIR motif and a RING finger, was found in NeseNPV. Two NeseNPV ORFs (nese18 and nese19) were duplicates transcribed in opposite orientations from each other. NeseNPV did not have an AcMNPV ORF 2 homolog characterized as the baculovirus repeat ORF (
bro
). Six homologous regions (
hr
s) were located within the NeseNPV genome, each containing small palindromes embedded within direct repeats. A phylogenetic analysis was done to root the tree based upon the sequences of DNA polymerase genes of NeseNPV, 23 other baculoviruses, and other phyla. Baculovirus phylogeny was then constructed with 29 conserved genes from 24 baculovirus genomes.
Culex nigripalpus
nucleopolyhedrovirus (CuniNPV) was the most distantly related baculovirus, branching to the hymenopteran NeseNPV and the lepidopteran nucleopolyhedroviruses and granuloviruses.
Protection against Lethal Vaccinia Virus Challenge in HLA-A2 Transgenic Mice by Immunization with a Single CD8+T-Cell Peptide Epitope of Vaccinia and Variola Viruses
Authors: Snyder James T. , Belyakov Igor M. , Dzutsev Amiran , Lemonnier François , Berzofsky Jay A.
Published: June 2004

CD8+T lymphocytes have been shown to be involved in controlling poxvirus infection, but no protective cytotoxic T-lymphocyte (CTL) epitopes are defined for variola virus, the causative agent of smallpox, or for vaccinia virus. Of several peptides in vaccinia virus predicted to bind HLA-A2.1, three, VETFsm(498-506), A26L(6-14), and HRP2(74-82), were found to bind HLA-A2.1. Splenocytes from HLA-A2.1 transgenic mice immunized with vaccinia virus responded only to HRP2(74-82) at 1 week and to all three epitopes by ex vivo enzyme-linked immunosorbent spot (ELISPOT) assay at 4 weeks postimmunization. To determine if these epitopes could elicit a protective CD8+T-cell response, we challenged peptide-immunized HLA-A2.1 transgenic mice intranasally with a lethal dose of the WR strain of vaccinia virus. HRP2(74-82) peptide-immunized mice recovered from infection, while naïve mice died. Depletion of CD8+T cells eliminated protection. Protection of HHD-2 mice, lacking mouse class I major histocompatibility complex molecules, implicates CTLs restricted by human HLA-A2.1 as mediators of protection. These results suggest that HRP2(74-82), which is shared between vaccinia and variola viruses, may be a CD8+T-cell epitope of vaccinia virus that will provide cross-protection against smallpox in HLA-A2.1-positive individuals, representing almost half the population.
Subunit-Specific Analysis of the Human Immunodeficiency Virus Type 1 Reverse Transcriptase In Vivo
Authors: Mulky Alok , Sarafianos Stefan G. , Arnold Edward , Wu Xiaoyun , Kappes John C.
Published: June 2004

The human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) is a heterodimer comprised of two structurally distinct subunits (p51 and p66). Since p51 and p66 are derived from the same coding region, subunit-specific structure-function studies of RT have been conducted exclusively by in vitro biochemical approaches. To study RT subunit function in the context of infectious virus, we constructed an LTR-vpr-p51-IRES-p66 expression cassette in which the HIV-1
vpr
gene was fused in frame with p51, followed by an internal ribosome entry site (IRES) sequence and the p66 coding region. By coexpression with RT-deficient proviral DNA, we demonstrated that the p66 subunit is specifically and selectively packaged into virions as a Vpr-p51/p66 complex. Our analysis showed that cleavage by the viral protease liberates Vpr and generates functional heterodimeric RT (p51/p66) that supports HIV-1 reverse transcription and virus infection. By exploiting this novel
trans
-complementation approach, we demonstrated, for the first time with infectious virions, that the YMDD aspartates of p66 are both required and sufficient for RT polymerase function. Mutational analyses of the p51 YMDD aspartates indicated that they play an important structural role in p51 folding and subunit interactions that are required for the formation of an active RT heterodimer within infected cells. Understanding the role of the individual RT subunits in RNA- and DNA-dependent DNA synthesis is integral to our understanding of RT function. Our findings will lead to important new insights into the role of the p51 and p66 subunits in HIV-1 reverse transcription.
Human Monoclonal Antibody to Hepatitis C Virus E1 Glycoprotein That Blocks Virus Attachment and Viral Infectivity
Authors: Keck Zhen-Yong , Sung Vicky M. H. , Perkins Susan , Rowe Judy , Paul Sudhir , Liang T. Jake , Lai Michael M. C. , Foung Steven K. H.
Published: June 2004

Human antibodies elicited in response to hepatitis C virus (HCV) infection are anticipated to react with the native conformation of the viral envelope structure. Isolation of these antibodies as human monoclonal antibodies that block virus binding and entry will be useful in providing potential therapeutic reagents and for vaccine development. H-111, an antibody to HCV envelope 1 protein (E1) that maps to the YEVRNVSGVYH sequence and is located near the N terminus of E1 and is able to immunoprecipitate E1E2 heterodimers, is described. Binding of H-111 to HCV E1 genotypes 1a, 1b, 2b, and 3a indicates that the H-111 epitope is highly conserved. Sequence analysis of antibody V regions showed evidence of somatic and affinity maturation of H-111. Finally, H-111 blocks HCV-like particle binding to and HCV virion infection of target cells, suggesting the involvement of this epitope in virus binding and entry.
Human Immunodeficiency Virus Type 1 (HIV-1) Diversity at Time of Infection Is Not Restricted to Certain Risk Groups or Specific HIV-1 Subtypes
Authors: Sagar Manish , Kirkegaard Erin , Long E. Michelle , Celum Connie , Buchbinder Susan , Daar Eric S. , Overbaugh Julie
Published: June 2004

African women frequently acquire several genetically distinct human immunodeficiency virus type 1 (HIV-1) variants from a heterosexual partner, whereas the acquisition of multiple variants appears to be rare in men. To determine whether newly infected individuals in other risk groups acquire genetically diverse viruses, we examined the viral envelope sequences in plasma samples from 13 women and 4 men from the United States infected with subtype B viruses and 10 men from Kenya infected with non-subtype B viruses. HIV-1 envelope sequences differed by more than 2% in three U.S. women, one U.S. man, and one Kenyan man near the time of seroconversion. These findings suggest that early HIV-1 genetic diversity is not exclusive to women from Africa or to infection with any particular HIV-1 subtype.
Ex Vivo Phenotype and Frequency of Influenza Virus-Specific CD4 Memory T Cells
Authors: Lucas Michaela , Day Cheryl L. , Wyer Jessica R. , Cunliffe Sharon L. , Loughry Andrew , McMichael Andrew J. , Klenerman Paul
Published: June 2004

Recent advances in class II tetramer staining technology have allowed reliable direct ex vivo visualization of antigen-specific CD4 T cells. In order to define the frequency and phenotype of a prototype response to a nonpersistent pathogen, we have used such techniques to analyze influenza virus-specific memory CD4 T cells directly from blood. These responses are stably detectable ex vivo at low frequencies (range, 0.00012 to 0.0061% of CD4 T cells) and display a distinct “central memory” CD62L+phenotype.
TWO GEOMETRIC APPROACHES TO STUDY THE DECONFINEMENT PHASE TRANSITION IN (3+1)-DIMENSIONAL Z2 GAUGE THEORIES
Authors: GÜNDÜÇ SEMRA , DILAVER MEHMET , GÜNDÜÇ YIĞIT
Published: June 2004

We have simulated (3+1)-dimensional finite temperature Z2 gauge theory by using Metropolis algorithm. We aimed to observe the deconfinement phase transitions by using geometric methods. In order to do so we have proposed two different methods which can be applied to three-dimensional effective spin model consisting of Polyakov loop variables. The first method is based on the studies of cluster structures of each configuration. For each temperature, configurations are obtained from a set of bond probability (P) values. At a certain probability, percolating clusters start to emerge. Unless the probability value coincides with the Coniglio–Klein probability value, the fluctuations are less than the actual fluctuations at the critical point. In this method the task is to identify the probability value which yields the highest peak in the diverging quantities on finite lattices. The second method uses the scaling function based on the surface renormalization, which is of geometric origin. Since this function is a scaling function, the measurements done on different-size lattices yield the same value at the critical point, apart from the correction to scaling terms. The linearization of the scaling function around the critical point yields the critical point and the critical exponents.
TESTING BOUNDARY CONDITIONS EFFICIENCY IN SIMULATIONS OF LONG-RANGE INTERACTING MAGNETIC MODELS
Authors: CANNAS SERGIO A. , LAPILLI CINTIA M. , STARIOLO DANIEL A.
Published: June 2004

Periodic boundary conditions have no unique implementation in magnetic systems where all spins interact with each other through a power law decaying interaction of the form 1/rα, r being the distance between spins. In this work we present a comparative study of the finite size effects oberved in numerical simulations by using first image and infinite image periodic boundary conditions in one- and two-dimensional spin systems with those interactions, including the ferromagnetic, anti-ferromagnetic and competitive interaction cases. Our results show no significative differences between the finite size effects produced by both boundary conditions when the low temperature phase has zero global magnetization, and it depends on the ratio α/d for systems with a low temperature ferromagnetic phase. In the last case the first image convention gives more stronger finite size effects than the other when the system enters into the classical regime α/d≤3/2.
GRAND CANONICAL SIMULATIONS OF HARD-DISK SYSTEMS BY SIMULATED TEMPERING
Authors: DÖGE GUNTER , MECKE KLAUS , MØLLER JESPER , STOYAN DIETRICH , WAAGEPETERSEN RASMUS P.
Published: June 2004

The melting transition of hard disks in two dimensions is still an unsolved problem and improved simulation algorithms may be helpful for its investigation. We suggest the application of simulating tempering for grand canonical hard-disk systems as an efficient alternative to the commonly-used Monte Carlo algorithms for canonical systems. This approach allows the direct study of the packing fraction as a function of the chemical potential even in the vicinity of the melting transition. Furthermore, estimates of several spatial characteristics including pair correlation function are studied in order to test the accuracy of the method and to analyze the melting transition in hard-disk systems. Our results seem to show that there is a weak first-order phase transition.
OPINION FORMATION ON A DETERMINISTIC PSEUDO-FRACTAL NETWORK
Authors: GONZÁLEZ M. C. , SOUSA A. O. , HERRMANN H. J.
Published: June 2004

The Sznajd model of socio-physics, with only a group of people sharing the same opinion can convince their neighbors, is applied to a scale-free random network modeled by a deterministic graph. We also study a model for elections based on the Sznajd model and the exponent obtained for the distribution of votes during the transient agrees with those obtained for real elections in Brazil and India. Our results are compared to those obtained using a Barabási–Albert scale-free network.
CRITICAL BEHAVIOR IN CELLULAR AUTOMATA ANIMAL DISEASE TRANSMISSION MODEL
Authors: MORLEY P. D. , CHANG JULIUS
Published: June 2004

Using cellular automata model, we simulate the British Government Policy (BGP) in the 2001 foot and mouth epidemic in Great Britain. When clinical symptoms of the disease appeared in a farm, there is mandatory slaughter (culling) of all livestock in an infected premise (IP). Those farms in the neighboring of an IP (contiguous premise, CP), are also culled, aka nearest neighbor interaction. Farms where the disease may be prevalent from animal, human, vehicle or airborne transmission (dangerous contact, DC), are additionally culled, aka next-to-nearest neighbor interactions and lightning factor. The resulting mathematical model possesses a phase transition, whereupon if the physical disease transmission kernel exceeds a critical value, catastrophic loss of animals ensues. The nonlocal disease transport probability can be as low as 0.01% per day and the disease can still be in the high mortality phase. We show that the fundamental equation for sustainable disease transport is the criticality equation for neutron fission cascade. Finally, we calculate that the percentage of culled animals that are actually healthy is ≈30%.
PHYSICS0.01: OBJECT-ORIENTED PROGRAMMING FOR EXACT DIAGONALIZATION
Authors: CHUNG MYUNG-HOON
Published: June 2004

A new system of library code is proposed and initiated. It is emphasized that the same terminologies as we find in our textbooks should be used for class names in the library code. This proposal is inspired by .NET of Microsoft. Several rules of thumb are suggested in order to obtain easy-readable coherent codes. As a first step, we present the library code for exact diagonalization in physics. When we build codes, we distinguish between model independent and dependent parts. For the model independent parts, we use the familiar terminologies like [Formula: see text], etc as class names. As an explicit example, we calculate ground state energy of a quantum dot, showing the triplet–singlet transition.
A ONE-DIMENSIONAL MODEL FOR NONEXPONENTIAL RELAXATION IN A SPIN GLASS OR GLASSY SYSTEM
Authors: AYDINER EKREM , KIYMAÇ KERİIM
Published: June 2004

In this research, we have presented the phase space of the so-called spin glass or glassy systems with a one-dimensional randomly-oriented diode network (RODN) in which the bonds between the lattice points are represented with diodes and these diodes are assumed to be fully conducting in the forward biased direction, whereas they are assumed to have some constraints, in the reverse direction, depending on the temperature and/or some other external effects. Thus, a particle's conduction (or transition) probability in the reverse direction through a diode like bond, pr, can be assumed to have values between zero and one. By employing the Monte Carlo simulation technique to the diffusion of particles through this network we have explored the relaxation mechanism, and their functional forms. Our simulation data indicates that for reverse transition probability values of pr=1.0 and 0.9, the time dependence of the relaxation data is exponential, on the other hand for pr<0.2 it may be represented by either power or logarithmic time dependence. However, in general, our data can be represented by a stretched exponential time dependence, exp (-(t/τ)α), especially in the limit of long t. Here the exponent α has values in the range of 0.3≤α≤1. For α≈1, obviously, exponential time dependence is regained. The value of α≈0.3, obtained for pr→0, is very interesting, since it is almost the same as the critical exponent, 1/3, reported in the literature for the lowest occupation probability of site points spanning percolation clusters.
SPECIAL OPTIMIZED RUNGE–KUTTA METHODS FOR IVPs WITH OSCILLATING SOLUTIONS
Authors: ANASTASSI Z. A. , SIMOS T. E.
Published: June 2004

In this paper we present a family of explicit Runge–Kutta methods of 5th algebraic order, one of which has variable coefficients, for the efficient solution of problems with oscillating solutions. Emphasis is placed on the phase-lag property in order to show its importance with regards to problems with oscillating solutions. Basic theory of Runge–Kutta methods, phase-lag analysis and construction of the new methods are described. Numerical results obtained for known problems show the efficiency of the new methods when they are compared with known methods in the literature. Furthermore we note that the method with variable coefficients appears to have much higher accuracy, which gets close to double precision, when the product of the frequency with the step-length approaches certain values. These values are constant and independent of the problem solved and depend only on the method used and more specifically on the expressions used to achieve higher algebraic order.
DETECTION OF ATMOSPHERIC TURBULENCE BY MULTIFRACTAL ANALYSIS USING WAVELETS
Authors: NICOLLET M. , LEMARCHAND A. , CAVACIUTI N.
Published: June 2004

We study the singularities of a temperature profile obtained by means of balloon measurements in the troposphere and lower stratosphere. The data give the evolution of the temperature as the altitude of the probe increases. We compare the scaling exponents deduced from the Wavelet Transform Modulus Maxima (WTMM) method and the structure function method. In the lower stratosphere, the variations in the multifractal properties with the altitude deduced from wavelets allow us to detect thin layers of about 200 m depth exhibiting atmospheric turbulence.
CHARACTERIZATION OF LASER PROPAGATION THROUGH TURBULENT MEDIA BY QUANTIFIERS BASED ON THE WAVELET TRANSFORM
Authors: ZUNINO LUCIANO , PÉREZ DARÍO G. , GARAVAGLIA MARIO , ROSSO OSVALDO A.
Published: June 2004

The propagation of a laser beam through turbulent media is modeled as a fractional Brownian motion (fBm). Time series corresponding to the center position of the laser spot (coordinates x and y) after traveling across air in turbulent motion, with different strength, are analyzed by the wavelet theory. Two quantifiers are calculated, the Hurst exponent, H, and the mean Normalized Total Wavelet Entropy, [Formula: see text]. It is verified that both quantifiers give complementary information about the turbulence.
REVIEW AND A MODEL OF PRE-SEISMIC ELECTROMAGNETIC EMISSIONS IN TERMS OF FRACTAL ELECTRODYNAMICS
Authors: EFTAXIAS K. , FRANGOS P. , KAPIRIS P. , POLYGIANNAKIS J. , KOPANAS J. , PERATZAKIS A. , SKOUNTZOS P. , JAGGARD D.
Published: June 2004

We introduce a new model of the generation of pre-seismic electromagnetic emissions, which explains the observed phenomenology in terms of its geometry and fractal electrodynamics. Accumulated evidence indicates that an earthquake can be viewed as a critical phenomenon culminating in a large event that corresponds to a type of critical point. The principle feature of criticality is the fractal organization in both space and time. Earthquakes display a complex spatio-temporal behavior: in addition to the regularity in the rate of occurrence (e.g. Gutenberg-Richter law, Omori law), the spatial distribution of epicenters is fractal and earthquakes occur on a fractal structure of faults. Thus, the hypothesis that the fault develops as a fractal is reasonable. A mounting body of laboratory evidence suggests that micro-fracturing of rocks are associated with the appearance of spontaneous charge production and transient electromagnetic emissions (EME). The emitting, diffusing and recombination charge accompanying the micro-fracturing, can act as current generated during the crack opening. In this view, an active crack or rupture, can be simulated by a "radiating element." The idea is that a fractal geo-antenna (FGA) can be formed as an array of line elements having a fractal distribution on the ground surface as the critical point is approached. We test this idea in terms of fractal electrodynamics: we argue that the precursory VLF-VHF EM signals associated with recent earthquakes in Greece are governed by characteristics (e.g. scaling laws, temporal evolution of the spectrum content, broad band spectrum region and accelerating emission rate) predicted by fractal electrodynamics.
EXPLORING MULTI-RESOLUTION AND MULTI-SCALING VOLATILITY FEATURES
Authors: CAPOBIANCO ENRICO
Published: June 2004

One of the most recent results in empirical finance is the achievement of an accuracy gain for the volatility estimates from the use of high-frequency samples. In many applications, for instance, the observed intra-day data become the best informative source of estimation for the daily volatilites. This information set, or filtration in probability terms, can in theory be optimally exploited while adopting an increasingly finer sampling rate, a fact which finds justification when assuming a stochastic characterization of the problem in terms of so-called semimartingales. These instruments are very useful for representing asset price dynamics, and in recent proposals supply realized and integrated volatility measures. The former volatility is the empirical approximation of the latter, an average of high frequency returns observed within a certain time frame. Semimartingales become suitable model tools by allowing for the quadratic variation principle to hold. This in turn means that the convergence of the realized to the integrated volatility can be verified; conversely, from both theoretical and experimental standpoints, the cumulative squared high frequency returns represent consistent estimators of the integrated volatility measure. The goal of this work is twofold: first, to show with simulations the quality of the convergence for time-based estimators, compared to that obtained when time-scale coordinate wavelet tranforms are considered. Second, to verify that special families of wavelet decompose returns and allow for multi-scaling features to be revealed, together with the possible presence of underlying nonlinear dynamics of stock index return volatility.
Recent Advances in Alcoholic Liver Disease II. Minireview: molecular mechanisms of alcoholic fatty liver
Authors: You Min , Crabb David W.
Published: June 2004

Alcohol has long been thought to cause fatty liver by way of altered NADH/NAD+ redox potential in the liver, which, in turn, inhibits fatty acid oxidation and the activity of tricarboxylic acid cycle reactions. More recent studies indicate that additional effects of ethanol both impair fat oxidation and stimulate lipogenesis. Ethanol interferes with DNA binding and transcription-activating properties of peroxisome proliferator-activated receptor-α (PPARα), as demonstrated with cultured cells and in ethanol-fed mice. Treatment of ethanol-fed mice with a PPARα agonist can reverse fatty liver even in the face of continued ethanol consumption. Ethanol also activated sterol regulatory element binding protein 1, inducing a battery of lipogenic enzymes. These effects may be due in part to inhibition of AMP-dependent protein kinase, reduction in plasma adiponectin, or increased levels of TNF-α in the liver. The understanding of these ethanol effects provides new therapeutic targets to reverse alcoholic fatty liver.
Procalcitonin and C-reactive protein during systemic inflammatory response syndrome, sepsis and organ dysfunction
Authors: Castelli Gian Paolo , Pognani Claudio , Meisner Michael , Stuani Antonio , Bellomi Daniela , Sgarbi Laura
Published: June 2004

Introduction

Both C-reactive protein (CRP) and procalcitonin (PCT) are accepted sepsis markers. However, there is still some debate concerning the correlation between their serum concentrations and sepsis severity. We hypothesised that PCT and CRP concentrations are different in patients with infection or with no infection at a similar severity of organ dysfunction or of systemic inflammatory response.

Patients and methods

One hundred and fifty adult intensive care unit patients were observed consecutively over a period of 10 days. PCT, CRP and infection parameters were compared among the following groups: no systemic inflammatory response syndrome (SIRS) (n = 15), SIRS (n = 15), sepsis/SS (n = 71) (including sepsis, severe sepsis and septic shock [n = 34, n = 22 and n = 15]), and trauma patients (n = 49, no infection).

Results

PCT and CRP concentrations were higher in patients in whom infection was diagnosed at comparable levels of organ dysfunction (infected patients, regression of median [ng/ml] PCT = -0.848 + 1.526 sequential organ failure assessment [SOFA] score, median [mg/l] CRP = 105.58 + 0.72 SOFA score; non-infected patients, PCT = 0.27 + 0.02 SOFA score, P < 0.0001; CRP = 84.53 - 0.19 SOFA score, P < 0.005), although correlation with the SOFA score was weak (R = 0.254, P < 0.001 for PCT, and R = 0.292, P < 0.001 for CRP). CRP levels were near their maximum already during lower SOFA scores, whereas maximum PCT concentrations were found at higher score levels (SOFA score > 12).

PCT and CRP concentrations were 1.58 ng/ml and 150 mg/l in patients with sepsis, 0.38 ng/ml and 51 mg/l in the SIRS patients (P < 0.05, Mann–Whitney U-test), and 0.14 ng/ml and 72 mg/l in the patients with no SIRS (P < 0.05). The kinetics of both parameters were also different, and PCT concentrations reacted more quickly than CRP.

Conclusions

PCT and CRP levels are related to the severity of organ dysfunction, but concentrations are still higher during infection. Different sensitivities and kinetics indicate a different clinical use for both parameters.
Collaborating on Convergent Technologies: Education and Practice
Authors: GORMAN MICHAEL E.
Published: June 2004

Abstract: Converging technologies will require collaboration across disciplines. A good metaphor for such collaborations is the kind of trading zone that emerges whenever human beings from different cultures interact. NBIC must avoid trading zones that are dominated by one discipline or set of interests and instead encourage multiple stakeholders to form a shared mental model of what needs to be accomplished. An example is drawn from current work on societal dimensions of nanotechnology. Students need to gain experience working in such trading zones, in addition to acquiring disciplinary depth.
Converging Technologies for Enhancing Human Performance: Science and Business Perspectives
Authors: SPOHRER JAMES C. , ENGELBART DOUGLAS C.
Published: June 2004

Abstract: Our goal is to provide a rough sketch of some of the possible implications of converging technologies for enhancing human performance (Roco and Bainbridge, 2002) from both a science and a business perspective. Converging technologies refers to a type of coevolutionary progress that is characterized by rapid advances across multiple areas of technology (nano‐bio‐info‐cogno or NBIC), accelerated by interdisciplinary cross‐fertilization as the advances in one area spill over and speed progress in other areas. The rapid, multi‐front progress characteristic of converging technologies results in better technological capabilities which are faster and cheaper, and can be broadly applied for many different purposes. In this paper, we specifically explore applications of converging technologies for enhancing human performance, that is, enhancing our human ability to achieve goals both individually and collectively. These applications hold the promise to make people healthier, wealthier, and wiser as well as to make businesses more responsive, resilient, and adaptive.
Systems Theory and the Ethics of Human Enhancement: A Framework for NBIC Convergence
Authors: KHUSHF GEORGE
Published: June 2004

Abstract: Representatives from government and the private sector recommend a major, cooperative initiative directed toward using NBIC (nano‐, bio‐, info‐, and cogno‐) technologies for human enhancement. By appropriately seeding the convergence of NBIC domains, they believe that the rate of development can be both accelerated and simultaneously channeled to avoid adverse risk and advance human good. However, to accomplish these goals, leaders of the convergence efforts identified as a major intellectual barrier the “development of a hierarchical architecture for integrating science across many scales, disciplines, and data modalities.” Such a holistic framework requires a radical rethinking of the nature of science and engineering, and, beyond this, is also necessary for addressing their normative ethical and societal implications. In the first part of this essay, I consider the claim that a new view of science and engineering is needed. After reviewing the central features of a classical view of science, I consider aspects of the nano‐revolution, showing why the classical conception is inappropriate and how a systems‐oriented perspective is responsive to the character of this new science. I then consider how both science and engineering are transformed, calling into question older dichotomies between pure and applied domains. With the reworking of this distinction comes opportunities for rethinking the relation between science and the humanities more generally, which is necessary if we are to more appropriately address normative ethical aspects of the convergence initiative. After providing this groundwork for the needed hierarchical architecture, I consider a useful example of how a systems perspective might guide NBIC convergence. In the 1960s–1990s George Engel advocated a systems‐theoretic model as an alternative to a more reductionistic “biomedical model” in medicine, and he did it for the exact same reasons as those advocated by the leaders of the NBIC convergence; namely, it embodies a more appropriate notion of science and enables one to address ethical aspects of medicine that were insufficiently addressed in the older model. By reviewing Engel's “biopsychosocial model” we can learn important lessons for developing the needed NBIC framework. I close by extending Engel's model so that it addresses all areas of enhancement envisioned as a part of NBIC convergence, and then identify areas where future research is still needed.
The Evolution of Semantic Systems
Authors: BAINBRIDGE WILLIAM SIMS
Published: June 2004

Abstract: Semantic or cultural systems are sets of concepts connected by meaningful relationships, and they exhibit properties similar to those of populations of biological organisms. Drawing upon ideas from evolutionary biology and methods from information technology, this article explores the potential for research and engineering on the evolution of semantic systems. Such work in cultural genetics requires two things: (1) a rigorous but evolving taxonomic system to categorize cultural artifacts, elements, and clusters, and (2) a set of hypotheses about the processes that cause evolutionary change. This article illustrates systematic approaches to cultural taxonomy with data on the popular ideology of the space program, science fiction motion pictures, nanotechnology books, and nanotechnology research grants. It offers hypotheses derived from evolutionary and population biology that might be useful in explaining cultural evolution.
How the Legal System Should Change as a Result of Converging Technologies
Authors: MILLER SONIA E.
Published: June 2004

Abstract:A forecast is given for how the legal system will change to meet some of the challenges for improvement that converging technologies raise for society.
Designing The Future: NBIC Technologies and Human Performance Enhancement
Authors: CANTON JAMES
Published: June 2004

Abstract: Never before has any civilization had the unique opportunity to enhance human performance on the scale that we will face in the near future. The convergence of nanotechnology, biotechnology, information technology, and cognitive science (NBIC) is creating a set of powerful tools that have the potential to significantly enhance human performance as well as transform society, science, economics, and human evolution. As the NBIC convergence becomes more understood, the possibility that we may be able to enhance human performance in the three domains of therapy, augmentation, and designed evolution will become anticipated and even expected. In addition, NBIC convergence represents entirely new challenges for scientists, policymakers, and business leaders who will have, for the first time, vast new and powerful tools to shape markets, societies, and lifestyles. The emergence of NBIC convergence will challenge us in new ways to balance risk and return, threat and opportunity, and social responsibility and competitive advantage as we step into the 21st century.
To Think Bigger Thoughts: Why the Human Cognome Project Requires Visual Language Tools to Address Social Messes
Authors: HORN ROBERT E.
Published: June 2004

Abstract: The need and use of visual languages in complex situations is outlined.
Neurotechnology and Society (2010–2060)
Authors: LYNCH ZACK
Published: June 2004

Abstract: To illuminate the societal implications of NBIC (nano‐bio‐info‐cogno) technologies it is critical to place them within a broad historical context. By viewing recent human history as a series of techno‐economic waves with accompanying socio‐political responses, a framework emerges that can be used to understand how business, politics, and human culture will be affected by NBIC technologies. One important development that the NBIC convergence is making possible is neurotechnology, the set of tools that can influence the human central nervous system, especially the brain. The diffusion of neurotechnology will give rise to a new type of human society—a post‐industrial, post‐informational neurosociety.
Long-Range Reserve Crew Manpower Planning
Authors: Sohoni Milind G. , Johnson Ellis L. , Bailey T. Glenn
Published: June 2004

Airlines are continually faced with the challenge of efficient utilization of their cockpit crew resources. In addition to regular flying crews, airlines maintain significant reserve staffing levels to meet contractual obligations and provide smooth daily operations. Most airlines also depend on voluntary and involuntary flying by regular crews to cover trips that fall out of work schedules due to conflicts and disruptions (open time trips). These open time trips, combined with expected levels of voluntary and involuntary flying, affect reserve staffing levels; airlines must plan crew staffing in advance to meet resulting training and new-hire requirements. Inefficient operational reserve utilization can further affect long-range crew staffing, resulting in higher training and new-hire costs. The proposed optimization strategy to estimate long-range crew staffing combines operational reserve utilization and premium operational costs due to voluntary and involuntary flying with long-range business needs.
Capacity Expansion for Random Exponential Demand Growth with Lead Times
Authors: Ryan Sarah M.
Published: June 2004

The combination of demand uncertainty and a lead time for adding capacity creates the risk of capacity shortage during the lead time. We formulate a model of capacity expansion for uncertain exponential demand growth and deterministic expansion lead times when there is an obligation to provide a specified level of service. The service level, defined in terms of the ratio of expected lead-time shortage to installed capacity, is guaranteed by timing each expansion to begin when demand reaches a fixed proportion of the capacity position. Under this timing rule, the optimal facilities to install can be determined by solving an equivalent deterministic problem without lead times. Numerical results show the effects of the demand parameters and lead-time length on the expansion timing. The interaction of timing with expansion size is explored for the case when continuous facility sizes are available with economies of scale.
Don't Fence Me In: Fragmented Markets for Technology and the Patent Acquisition Strategies of Firms
Authors: Ziedonis Rosemarie Ham
Published: June 2004

How do firms avoid being “fenced in” by owners of patented technologies used, perhaps unknowingly, in the design or manufacture of their products? This paper examines the conditions under which firms expand their own portfolios of patents in response to potential hold-up problems in markets for technology. Combining insights from transactions cost theory with recent scholarship on intellectual property and its exchange, I predict firms will patent more aggressively than otherwise expected when markets for technology are highly fragmented (i.e., ownership rights to external technologies are widely distributed); this effect should be more pronounced for firms with large investments in technology-specific assets and under a strong legal appropriability regime. Although these characteristics of firms and their external environments have been highlighted in the theoretical literature, prior research has not explored the extent to which such factors interact to shape the patenting behavior of firms. To empirically test these hypotheses, I develop a citations-based “fragmentation index” and estimate the determinants of patenting for 67 U.S. semiconductor firms between 1980 and 1994. Accumulating exclusionary rights of their own may enable firms to safeguard their investments in new technologies while foregoing some of the costs and delays associated with ex ante contracting.
50th Anniversary Article: Selection, Provisioning, Shared Fixed Costs, Maximum Closure, and Implications on Algorithmic Methods Today
Authors: Hochbaum Dorit S.
Published: June 2004

Motivated by applications in freight handling and open-pit mining, Rhys, Balinski, and Picard studied the problems of selection and closure in papers published in Management Science in 1970 and 1976. They identified efficient algorithms based on linear programming and maximum-flow/minimum-cut procedures to solve these problems. This research has had major impact well beyond the initial applications, reaching across three decades and inspiring work on numerous applications and extensions. The extensions are nontrivial optimization problems that are of theoretical interest. The applications ranged from evolving technologies, image segmentation, revealed preferences, pricing, adjusting utilities for consistencies, just-in-time production, solving certain integer programs in polynomial time, and providing efficient 2-approximation algorithms for a wide variety of hard problems. A recent generalization to a convex objective function has even produced novel solutions to prediction and Bayesian estimation problems. This paper surveys the streams of research stimulated by these papers as an example of the impact of Management Science on the optimization field and an illustration of the far-reaching implications of good original research.
Scheduling Commercials on Broadcast Television
Authors: Bollapragada Srinivas , Garbiras Marc
Published: June 2004

Television networks sell advertising slots to clients by the shows on which the commercials air. The networks determine the exact location in the show that a commercial will air at a later stage, usually close to the airdate of the show. There are several criteria the networks must meet in scheduling commercials in a show. The schedule should be such that no two commercials promoting competing products from different clients air in the same break. The audience ratings tend to be higher at the start and end of a commercial break than during the middle of the break. Therefore, advertisers generally prefer the first and last positions in a commercial segment, to those in the middle. TV networks normally promise their clients an equitable rotation of commercials among the positions within a commercial break. The scheduling of commercials on shows is traditionally done manually and is a cumbersome, time-intensive, and error-prone process. We formulate the commercial scheduling problem as an integer program and develop near-optimal heuristics for automatically scheduling the commercials to meet all the requirements. We implemented our algorithm at the National Broadcasting Company (NBC). In addition to reducing sales personnel costs by automating the scheduling of commercials, our work has increased customer satisfaction by minimizing errors in meeting customer requirements.
Shoot-Look-Shoot: A Review and Extension
Authors: Glazebrook Kevin , Washburn Alan
Published: June 2004

We consider the optimal use of information in shooting at a collection of targets, generally with the object of maximizing the average number (or value) of targets killed. The shooting problem is viewed as a Markov decision process, and the modal solution technique is stochastic dynamic programming. Information obtained about target status may or may not be perfect, and there may or may not be constraints on the number of shots. Previous results are reviewed, and some new results are obtained.
Monotone Forecasts
Authors: Haksöz Çağrı , Seshadri Sridhar
Published: June 2004

In this paper we provide necessary and sufficient conditions for the distribution of demand in the future to be stochastically increasing in the demand that has been observed in the past. We base our analysis on the multiperiod inventory model examined by Eppen and Iyer (1997). In the process of establishing the necessary and sufficient conditions we develop a new property called the sequential monotone likelihood ratio property.
The Infinite Horizon Periodic Review Problem with Setup Costs and Capacity Constraints: A Partial Characterization of the Optimal Policy
Authors: Shaoxiang Chen
Published: June 2004

The one-item, periodic review production and inventory system has been extensively studied in literature. Theories have been established for various basic constructs of the system of either finite or infinite horizon, except for the case where production capacity is finite and production cost contains a fixed (as well as a variable) component. It was conjectured in earlier research papers that the modified (s, S) policy would be optimal to the finite-capacity, fixed-cost model in infinite horizon. This paper studies the long-run limiting behavior of such systems. It proves that the limiting cost function exists, and there exist stationary policies that are optimal in the long run. The optimal policy, however, is not of the modified (s, S) type in general, but continues to exhibit the X-Y band structure: Whenever the inventory level drops below X, order up to capacity; when the inventory level is above Y, do nothing. When the inventory level is between X and Y, however, the ordering pattern seems to be changing from problem to problem. Nevertheless, based on a concept called (C, K)-convexity, introduced in this paper, the X-Y band is shown to be no more than one capacity of width. One calculation for the bounds on such X and Y boundaries that are tight in some cases is also provided. By exploring the X-Y band structure, a linear program model is proposed to find the optimal policy completely. Finally, an attempt is made to compare “the best modified (s, S) policy” with the optimal one, and a numerical example indicates that the deviation may be more than 11% in cost performance.
Friends or Strangers? Firm-Specific Uncertainty, Market Uncertainty, and Network Partner Selection
Authors: Beckman Christine M. , Haunschild Pamela R. , Phillips Damon J.
Published: June 2004

In this study, we address the topic of interorganizational network change by exploring factors that affect the choice of alliance and interlock partners. While many studies have been devoted to investigating various factors driving network partner choice, there is also an interesting and unexplored tension in this body of work. On the one hand, much work emphasizes change in social structure—showing that firms expand networks by forming new relationships with new partners. At the same time, other scholars emphasize stability of social structure—showing that firms tend to choose past exchange partners. We seek to reconcile this tension by proposing that firms form new relationships with new partners as a form of exploration, and form additional relationships with existing partners as a form of exploitation (March 1991). Further, whether exploration or exploitation is chosen depends on the type of uncertainty that firms are facing: whether it is firm-specific or market-level uncertainty. We test our hypotheses using data on both interlock and alliance networks for the 300 largest U.S. firms during the 1988–1993 period. The results provide some evidence that whether networks are stable or changing depends on the type of uncertainty experienced by firms.
The Corporate Objective Revisited
Authors: Sundaram Anant K. , Inkpen Andrew C.
Published: June 2004

The stock market convulsions and corporate scandals of 2001 and 2002 have reignited debate on the purposes of the corporation and, in particular, the goal of shareholder value maximization. We revisit the debate, re-examine the traditional rationales, and develop a set of new arguments for why the preferred objective function for the corporation must unambiguously continue to be the one that says “maximize shareholder value.” We trace the origins of the debates from the late nineteenth century, their implications for accepted law and practice of corporate governance in the United States, and their reflection in shareholder versus stakeholder views in the organization studies literature and contractarian versus communitarian views in the legal literature. We address in detail possible critiques of the shareholder value maximization view. Although we recognize certain boundary constraints to our arguments, we conclude that the issues raised by such critiques and constraints are not unique to the shareholder value maximization view, but will exist even if the firm is managed on behalf of nonshareowning stakeholders.
The Psychobiological Model: Towards a New Theory of Computer-Mediated Communication Based on Darwinian Evolution
Authors: Kock Ned
Published: June 2004

This article reviews theories of organizational communication with a special emphasis on theories that have been used to explain computer-mediated communication phenomena. Among the theories reviewed, two—social presence and media richness—are identified as problematic and as posing obstacles to future theoretical development. While shortcomings of these theories have been identified in the past, some of these theories' predictions have been supported by empirical evidence. It is argued that this theoretical dilemma can be resolved based upon principles derived from a modern version of Darwin's theory of evolution by natural selection and the application of those principles to the understanding of human evolution. A new theoretical model called the psychobiological model is developed, which predicts variations in cognitive effort in computer-mediated collaborative tasks. The model proposes that there is a negative causal link between the “naturalness” of a computer-mediated communication medium, which is the similarity of the medium to the face-to-face medium, and the cognitive effort required from an individual using the medium for knowledge transfer. The model also states that this link is counterbalanced by what are referred to as “schema alignment” and “cognitive adaptation.” The schema alignment construct refers to the similarity between the mental schemas of an individual and those of other participant(s). The cognitive adaptation construct refers to an individual's level of schema development associated with the use of a particular medium. Finally, the model states that the degree to which the medium supports an individual's ability to convey and listen to speech is particularly significant in defining its naturalness, more so than the medium's degree of support for the use of facial expressions and body language. An example is offered of how the psychobiological model can be tested in the context provided by the customer support area of an online broker.