bluuebunny/crossref_metadata_2025 huggingface dataset:
UBIQUITIN AND THE CONTROL OF PROTEIN FATE IN THE SECRETORY AND ENDOCYTIC PATHWAYS
Authors: Bonifacino Juan S. , Weissman Allan M.
Published: July 2002

▪ Abstract  The modification of proteins by chains of ubiquitin has long been known to mediate targeting of cytosolic and nuclear proteins for degradation by proteasomes. In this article, we discuss recent developments that reveal the involvement of ubiquitin in the degradation of proteins retained within the endoplasmic reticulum (ER) and in the internalization of plasma membrane proteins. Both luminal and transmembrane proteins retained in the ER are now known to be retrotranslocated into the cytosol in a process that involves ER chaperones and components of the protein import machinery. Once exposed to the cytosolic milieu, retro-translocated proteins are degraded by the proteasome, in most cases following polyubiquitination. There is growing evidence that both the ubiquitin-conjugating machinery and proteasomes may be associated with the cytosolic face of the ER membrane and that they could be functionally coupled to the process of retro-translocation. The ubiquitination of plasma membrane proteins, on the other hand, mediates internalization of the proteins, which in most cases is followed by lysosomal/vacuolar degradation. There is, however, a well-documented case of a plasma membrane protein (the c-Met receptor) for which ubiquitination results in proteasomal degradation. These recent findings imply that ubiquitin plays more diverse roles in the regulation of the fate of cellular proteins than originally anticipated.
SPILLING BREAKERS
Authors: Duncan JH
Published: July 2002

▪ Abstract  Spilling breakers receive much less attention from casual observers of the ocean surface than their more dramatic and powerful plunging counterparts. However, spilling breakers probably occur more frequently than plunging breakers and are important contributors to turbulence, spray, and bubble generation at the water surface. Recent research has concentrated primarily on relatively weak and/or short-wavelength spillers whose crests are strongly affected by surface tension forces both during wave steepening and the resulting turbulent free-surface flow. When surface tension forces are dominant, the free surface does not overturn or splash during the breaking process but undergoes some unique and interesting motions. In this review, recent research contributions are discussed and placed in the context of spilling behavior over a wide range of wavelengths and breaking intensities.
Williams Syndrome and Related Disorders
Authors: Morris, M.D Colleen A. , Mervis, Ph.D Carolyn B.
Published: July 2002

Three clinical conditions displaying phenotypic overlap have been linked to mutation or deletion of the elastin gene at 7q11.23. Supravalvar aortic stenosis, an autosomal dominant disorder characterized by elastin arteriopathy, is caused by mutation or intragenic deletions of ELN resulting in loss of function. Autosomal dominant cutis laxa, a primarily cutaneous condition, is the result of frameshift mutations at ELN that cause a dominant-negative effect on elastic fiber structure. Williams syndrome, a neurodevelopmental disorder is due to a 1.5 Mb deletion that includes ELN and at least 15 contiguous genes. The disorder is characterized by dysmorphic facies, mental retardation or learning difficulties, elastin arteriopathy, a unique cognitive profile of relative strength in auditory rote memory and language and extreme weakness in visuospatial constructive cognition, and a typical personality that includes overfriendliness, anxiety, and attention problems. The understanding of these disorders has progressed from phenotypic description to identification of causative mutations and insight into pathogenetic mechanisms for some aspects of the phenotype.
Tribochemical Polishing
Authors: Muratov Viktor A. , Fischer Traugott E.
Published: July 2002

▪ Abstract  Tribochemical polishing, a novel polishing technique, is based on the dissolution of material, stimulated by simultaneous friction at contacting asperities. It uses hard polishing pads (cast iron, stainless steel, ceramic) and a polishing solution free of abrasive particles. Tribochemical polishing of ceramics (Si3N4, SiC) and tungsten has been demonstrated. Surface roughnesses less than 1 nm and removal rates up to 3 μm per h have been achieved. A comparison with other polishing methods (e.g. chemical mechanical polishing) is given and the basic mechanisms governing the material removal are described. The possible chemical reactions between the polishing solution (H2O, CrO3) and the silicon nitride are discussed and compared with available literature.
PROSTATE CARCINOMA
Authors: Andriole, M.D Gerald L. , Catalona, M.D William J.
Published: July 2002

▪ Abstract  Over the last several years, the development of prostate-specific antigen (PSA) testing and technical refinements of anatomic radical prostatectomy have revolutionized the care of patients with prostate cancer. Serum PSA testing often allows early diagnosis of organ-confined prostate cancer. Anatomical radical prostatectomy has a high probability of completely eradicating these tumors, with minimal long-term morbidity. Use of PSA testing after therapy confirms the long-term ability of surgery to eradicate early-stage prostate cancer.
DEVELOPMENT AND BIOMEDICAL TESTING OF MILITARY OPERATIONAL RATIONS
Authors: Friedl Karl E. , Hoyt Reed W.
Published: July 2002

▪ Abstract  This article gives a brief history of military nutrition research in this century and reviews recent advances made through field testing. Although modern rations are nutritionally complete, ration developers are challenged to improve palatability to promote increased intakes in field training and combat settings. The principal goal for military nutritionists is to identify the optimal macronutrient mix and specific ration components that sustain a soldier's performance in the face of operational stressors such as sleep deprivation, intense physical activity, climatic extremes, and hypobaric hypoxia. Energy expenditures during typical field-training exercises average approximately 4000 kcal/day, whereas energy intakes are usually 3000 kcal/day or less when operational rations are consumed. One way to ameliorate the effects of this shortfall is to provide soldiers with a carbohydrate beverage supplement.
Molecular Approach to Adenosine Receptors: Receptor-Mediated Mechanisms of Tissue Protection
Authors: Linden J
Published: July 2002

Adenosine accumulation during ischemia and inflammation protects tissues from injury. In ischemic tissues adenosine accumulates due to inhibition of adenosine kinase, and in inflamed tissues adenosine is formed from adenine nucleotides that are released from many cells including platelets, mast cells, nerves, and endothelium. Nucleotides are rapidly converted to adenosine by a family of ecto-nucleotidases including CD39 and CD73. Activation of A1and possibly A3adenosine receptors (ARs) protects heart and other tissues by preconditioning through a pathway including protein kinase C and mitochondrial KATPchannels. Activation of A2Areceptors limits reperfusion injury by inhibiting inflammatory processes in neutrophils, platelets, macrophages and T cells. Adenosine produces proinflammatory responses mediated by receptors that vary among species; A3and A2Breceptors mediate degranulation of rodent and human or canine mast cells, respectively. Novel adenosine receptor subtype–selective ligands have recently been developed. These include MRS1754 (A2Bblocker), MRS1220 (A3blocker), MRE 3008F20 (human A3blocker), MRS1523 (rat A3blocker), and ATL146e (A2Aagonist). These new pharmacologic tools will help investigators to sort out how adenosine protects tissues from injury and to identify new therapeutic agents that hold promise for the treatment of inflammatory and ischemic diseases.
SUBFEMTOSECOND PROCESSES IN STRONG LASER FIELDS
Authors: Corkum Paul B. , Ivanov Misha Yu. , Wright James S.
Published: July 2002

▪ Abstract  Strong field atomic and molecular interactions can be understood by following electronic dynamics inside the laser cycle. This quasistatic perspective introduces the subfemtosecond time scale into strong-field dynamics through time-dependent Born-Oppenheimer surfaces. We discuss both theoretical and experimental results in atomic and molecular ionization and dissociation with applications to femtochemistry. An all-optical Coulomb explosion method for determining time-dependent molecular structure and properties is demonstrated. The concept of time-dependent Born-Oppenheimer surfaces is used to study molecular dissociation and exchange reactions in infrared fields.
LIGHT-EMITTINGELECTROCHEMICALPROCESSES
Authors: Armstrong Neal R , Wightman R Mark , Gross Erin M
Published: July 2002

▪ Abstract  Electrochemical processes leading to light emission are reviewed, with emphasis on aspects of this subject relevant to the understanding and optimization of electrogenerated luminescence (EL) in organic thin-film materials. The basic energetic requirements of light emission from electrochemically initiated solution redox reactions [electrogenerated chemiluminescence (ECL)] are reviewed first. This review is followed by a discussion of light-emitting electrochemical processes that have been observed in hybrids of ionically conducting polymers and electronically conducting polymers. Finally, the features of EL in insulating polymers and molecular thin films are reviewed, along with recent electrochemical and ECL studies of the small-molecule components of certain organic light-emitting diodes. These studies provide a conceptual framework for understanding and optimizing these materials and the EL process.
Gastrin, CCK, Signaling, and Cancer
Authors: Rozengurt Enrique , Walsh John H
Published: July 2002

▪ Abstract  Gastrin, produced by G cells in the gastric antrum, has been identified as the circulating hormone responsible for stimulation of acid secretion from the parietal cell. Gastrin also acts as a potent cell-growth factor that has been implicated in a variety of normal and abnormal biological processes including maintenance of the gastric mucosa, proliferation of enterochromaffin-like cells, and neoplastic transformation. Here, we review the models used to study the effects of gastrin on cell proliferation in vivo and in vitro with respect to mechanisms by which this hormone might influence normal and cancerous cell growth. Specifically, human and animal models of hypergastrinemia and hypogastrinemia have been described in vivo, and several cells that express cholecystokinin (CCK)B/gastrin receptors have been used for analysis of intracellular signaling pathways initiated by biologically active amidated gastrins. The binding of gastrin or CCK to their common cognate receptor triggers the activation of multiple signal transduction pathways that relay the mitogenic signal to the nucleus and promote cell proliferation. A rapid increase in the synthesis of lipid-derived second messengers with subsequent activation of protein phosphorylation cascades, including mitogen-activated protein kinase, is an important early response to these signaling peptides. Gastrin and CCK also induce rapid Rho-dependent actin remodeling and coordinate tyrosine phosphorylation of cellular proteins including the non-receptor tyrosine kinases p125fak and Src and the adaptor proteins p130cas and paxillin. This article reviews recent advances in defining the role of gastrin and CCK in the control of cell proliferation in normal and cancer cells and in dissecting the signal transduction pathways that mediate the proliferative responses induced by these hormonal GI peptides in a variety of normal and cancer cell model systems.
Consumer Health Plan Choice: Current Knowledge and Future Directions
Authors: Scanlon Dennis P. , Chernew Michael , Lave Judith R.
Published: July 2002

▪ Abstract  A keystone of the competitive strategy in health insurance markets is the assumption that “consumers” can make informed choices based on the costs and quality of competing health plans, and that selection effects are not large. However, little is known about how individuals use information other than price in the decision making process. This review summarizes the state of knowledge about how individuals make choices among health plans and outlines an agenda for future research.

We find that the existing literature on health plan choice is no longer sufficient given the widespread growth and acceptance of managed care, and the increased proportion of consumers' income now going toward the purchase of health plans. Instead, today's environment of health plan choice requires better understanding of how plan attributes other than price influence plan choice, how other variables such as health status interact with plan attributes in the decision making process, and how specific populations differ from one another in terms of the sensitivity of their health plan choices to these different types of variables.
Pharmacoeconomics: State of the Art in 1997
Authors: Schulman Kevin A. , Linas Benjamin P.
Published: July 2002

▪ Abstract  Economic evaluation of pharmaceutical products, or pharmacoeconomics, is a rapidly growing area of research. Pharmacoeconomic evaluation is important in helping clinicians and managers make choices about new pharmaceutical products and in helping patients obtain access to new medications. Over the last few years, the scientific rigor of this field has increased greatly. At the same time, new types of analysis, based on prospective data collection, have been developed. This article reviews the basic concept of pharmacoeconomics, the types of data available for economic evaluation, and the “state of the art” in pharmacoeconomics as reported in the medical literature.
Involvement of Myoendothelial Gap Junctions in the Actions of Endothelium-Derived Hyperpolarizing Factor
Authors: Sandow Shaun L. , Tare Marianne , Coleman Harold A. , Hill Caryl E. , Parkington Helena C.
Published: July 2002

Abstract
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The nature of the vasodilator endothelium-derived hyperpolarizing factor (EDHF) is controversial, putatively involving diffusible factors and/or electrotonic spread of hyperpolarization generated in the endothelium via myoendothelial gap junctions (MEGJs). In this study, we investigated the relationship between the existence of MEGJs, endothelial cell (EC) hyperpolarization, and EDHF-attributed smooth muscle cell (SMC) hyperpolarization in two different arteries: the rat mesenteric artery, where EDHF-mediated vasodilation is prominent, and the femoral artery, where there is no EDHF-dependent relaxation. In the rat mesenteric artery, stimulation of the endothelium with acetylcholine (ACh) evoked hyperpolarization of both ECs and SMCs, and characteristic pentalaminar MEGJs were found connecting the two cell layers. In contrast, in the femoral artery, ACh evoked hyperpolarization in only ECs but not in SMCs, and no MEGJs were present. Selective hyperpolarization of ECs or SMCs evoked hyperpolarization in the other cell type in the mesenteric artery but not in the femoral artery. Disruption of gap junctional coupling using the peptide Gap 27 markedly reduced the ACh-induced hyperpolarization in SMCs, but not in ECs, of the mesenteric artery. These results show that transfer of EC hyperpolarization or of a small molecule to SMCs through MEGJs is essential and sufficient to explain EDHF.
Trust Building, Trust Breaking: The Dilemma of NATO Enlargement
Authors: Kydd Andrew
Published: July 2002

Barbara Koremenos, Charles Lipson, and Duncan Snidal conjecture that the conditions of membership in international institutions will grow more restrictive as a response to uncertainty about state preferences. Membership criteria will act as a signaling device—states more committed to cooperation will be willing to meet the criteria, whereas those less committed to cooperation will not. The recent enlargement of NATO to include the former Warsaw Pact members Poland, Hungary, and the Czech Republic illustrates this logic. The potential candidates for admission had to meet standards with respect to democratization, civilian control over the military, and the resolution of border and ethnic disputes with neighbors. These criteria served to identify the more cooperative potential members and to encourage cooperative behavior among those who aspired to membership. However, NATO enlargement came at a price. Although trust was built and cooperation fostered between the East European states that gained membership, trust was broken and cooperation harmed between NATO and Russia. This unfortunate outcome represents a dilemma that arises in the expansion of a security community: While expanding the security community enlarges the zone of peace and mutual trust, it may generate fear among those still on the outside, who view it as a potentially hostile alliance. I present a game-theoretic analysis of this dilemma and analyze the conditions under which it arises.
Re-Enlistment Patterns of Civil War Soldiers
Authors: Robertson John
Published: July 2002

The results of a demographic profile of age, occupation, and prewar residence of western Pennsylvania soldiers—created from enlistment and muster rolls, and examined at enlistment, at the end of 1863, and after re-enlistment—when placed within the context of individual soldiers' letters and the social history of western Pennsylvania, show that soldiers with rural backgrounds and poor occupations re-enlisted at higher rates than soldiers with urban backgrounds and better occupations. The reason for the difference lies in the greater opportunities available to civilians in the city.
The Construction of Jackson Pollock's Fractal Drip Paintings
Authors: Taylor Richard P. , Micolich Adam P. , Jonas David
Published: July 2002

Between 1943 and 1952, Jackson Pollock created patterns by dripping paint onto horizontal canvases. In 1999 the authors identified the patterns as fractal. Ending 50 years of debate over the content of his paintings, the results raised the more general question of how a human being could create fractals. The authors, by analyzing film that recorded the evolution of Pollock's patterns as a function of time, show that the fractals resulted from a systematic construction process involving multiple layers of painted patterns. These results are interpreted within the context of recent visual perception studies of fractal patterns.
Philosophy and Visual Representation: Imaging the Impossible
Authors: DiSalvo Carl Francis
Published: July 2002

Visualization techniques used in science and the arts for the advanced analysis of information and theories can and should be similarly used in the humanities. Within the discipline of philosophy there are both the possibility and the necessity to examine and present ideas using visualization techniques. The author created a CD-ROM entitled Blinded … in an attempt to use visualization techniques to analyze and represent a metaphysical action proposed by the French philosopher George Bataille. He discusses the creation of that work and the theories involved in the conjunction of philosophy and visualization.
Illicit Remnant Movement: An Argument for Feature-Driven Movement
Authors: Takano Yuji
Published: July 2002

This article discusses previously unnoticed empirical effects of the operation Attract/Move F. Certain illicit cases of so-called remnant movement are accounted for if the primitive operation inducing move-ment is feature movement and all category movement is feature-driven, as is claimed by the Attract/Move F hypothesis. Since the relevant cases of illicit remnant movement remain unaccounted for under the traditional Move a hypothesis, which claims that the primitive opera-tion is category movement, the present discussion lends new empirical support to the feature-driven view of movement.
On the (Non)complementarity of θ-Theory and Checking Theory
Authors: López Luis
Published: July 2002

Chomsky (1995) proposes that the θ system and the checking system form two complementary modules. As a consequence both subjects and objects must form nontrivial chains to check their formal features with a functional category (T and v, respectively). I argue that objects and exceptional-Case-marking subjects check their formal features with a lexical verb, whose domain is therefore both θ role assigning and feature checking. I showthat discarding the complementarity assumption in this manner results in a more “bare” theory of the computational system as well as several empirical advantages.
From Hell to Polarity: “Aggressively Non-D-Linked” Wh-Phrases as Polarity Items
Authors: Dikken Marcel den , Giannakidou Anastasia
Published: July 2002

Pesetsky's (1987) “aggressively non-D-linked”wh-phrases (likewho the hell; hereinafter, wh-the-hell phrases) exhibit a variety of syntactic and semantic peculiarities, including the fact that they cannot occur in situ and do not support nonecho readings when occurring in root multiple questions. While these are familiar from the literature (albeit less than fully understood), our focus will be on a previously unnoted property of wh-the-hell phrases: the fact that their distribution (in single wh-questions) matches that of polarity items (PIs). We lay out the key data supporting this claim, embed the PI nature of wh-the-hell phrases in the theory of polarity developed in Giannakidou 1998, 1999, 2001, and establish the link between the lexical content of these phrases and their PI status by identifying wh-the-hell as a dependent PI. We subsequently exploit the PI status of wh-the-hell to explain the more familiar puzzles mentioned above, showing that these are not peculiarities specific to wh-the-hell but manifestations of the general properties of the class of PIs that wh-the-hell belongs to. The syntactic aspects of the polarity analysis of wh-the-hell are shown to have important consequences for the fundamental properties of wh-movement in English.
The Effects of Frontal Lobe Lesions on Goal Achievement in the Water Jug Task
Authors: Colvin Mary Kathryn , Dunbar Kevin , Grafman Jordan
Published: July 2002

Patients with prefrontal cortex lesions are impaired on a variety of planning and problem-solving tasks. We examined the problem-solving performance of 27 patients with focal frontal lobe damage on the Water Jug task. The Water Jug task has never been used to assess problem-solving ability in neurologically impaired patients nor in functional neuroimaging studies, despite sharing structural similarities with other tasks sensitive to prefrontal cortex function, including the Tower of Hanoi, Tower of London, and Wisconsin Card Sorting Task (WCST). Our results demonstrate that the Water Jug task invokes a unique combination of problem-solving and planning strategies, allowing a more precise identification of frontal lobe lesion patients' cognitive deficits. All participants (patients and matched controls) appear to be utilizing a hill-climbing strategy that does not require sophisticated planning; however, frontal lobe lesion patients (FLLs) struggled to make required “counterintuitive moves” not predicted by this strategy and found within both solution paths. Left and bilateral FLLs were more impaired than right FLLs. Analysis of the left hemisphere brain regions encompassed by the lesions of these patients found that poor performance was linked to left dorsolateral prefrontal cortex damage. We propose that patients with left dorsolateral prefrontal cortex lesions have difficulty making a decision requiring the conceptual comparison of nonverbal stimuli, manipulation of select representations of potential solutions, and are unable to appropriately inhibit a response in keeping with the final goal.
GABA-ergic Modulation of Prefrontal Spatio-temporal Activation Pattern during Emotional Processing: A Combined fMRI/MEG Study with Placebo and Lorazepam
Authors: Northoff Georg , Witze Thomas , Richter Andre , Gessner Matthias , Schlagenhauf Florian , Fell Jürgen , Baumgart Frank , Kaulisch Thomas , Tempelmann Claus , Heinzel Alexander , Kötter Rolf , Hagner Tilman , Barge Bela , Hinrichs Hermann , Bogerts Bernhard , Scheich Henning , Heinze Hans-Jochen
Published: July 2002

Various prefrontal cortical regions have been shown to be activated during emotional stimulation, whereas neurochemical mechanisms underlying emotional processing in the prefrontal cortex remain unclear. We therefore investigated the influence of the GABA-A potentiator lorazepam on prefrontal cortical emotional—motor spatio-temporal activation pattern in a combined functional magnetic resonance imaging/magnetoencephalography study. Lorazepam led to the reversal in orbito-frontal activation pattern, a shift of the early magnetic field dipole from the orbito-frontal to medial prefrontal cortex, and alterations in premotor/motor cortical function during negative and positive emotional stimulation. It is concluded that negative emotional processing in the orbito-frontal cortex may be modulated either directly or indirectly by GABA-A receptors. Such a modulation of orbito-frontal cortical emotional function by lorazepam has to be distinguished from its effects on cortical motor function as being independent from the kind of processing either emotional or nonemotional.
Contributions of the Prefrontal Cortex and Basal Ganglia to Set Shifting
Authors: Ravizza Susan M. , Ciranni Michael A.
Published: July 2002

Impairments of set shifting have been associated with damage to both the prefrontal cortex (PFC) and to the basal ganglia. The purpose of these experiments was to determine whether damage to the PFC was associated with shifting impairments per se or whether any switching deficits could be attributed to a reduction of working memory capacity. In contrast, shifting impairments were expected for Parkinson patients regardless of memory load, given that these patients seem to have no cognitive deficits other than when having to shift set. To vary working memory demands, a cue to the relevant dimension (letter or shape) in an odd-man-out task was presented or withheld. Pathology to prefrontal areas associated with normal aging was not linked to shifting deficits when working memory load was reduced in a comparison of older and younger adults (Experiment 1). In contrast, set-shifting abilities were still impaired for stroke patients with prefrontal damage regardless of working memory demands (Experiment 2). Parkinson patients were relatively unimpaired on this task (Experiment 2), but began to display shifting deficits when response competition was present in the display (Experiment 3).
Neurons with Two Sites of Synaptic Integration Learn Invariant Representations
Authors: Körding Konrad P. , König Peter
Published: July 2002

Neurons in mammalian cerebral cortex combine specific responses with respect to some stimulus features with invariant responses to other stimulus features. For example, in primary visual cortex, complex cells code for orientation of a contour but ignore its position to a certain degree. In higher areas, such as the inferotemporal cortex, translation-invariant, rotation-invariant, and even view point-invariant responses can be observed. Such properties are of obvious interest to artificial systems performing tasks like pattern recognition. It remains to be resolved how such response properties develop in biological systems. Here we present an unsupervised learning rule that addresses this problem. It is based on a neuron model with two sites of synaptic integration, allowing qualitatively different effects of input to basal and apical dendritic trees, respectively. Without supervision, the system learns to extract invariance properties using temporal or spatial continuity of stimuli. Furthermore, top-down information can be smoothly integrated in the same framework. Thus, this model lends a physiological implementation to approaches of unsupervised learning of invariant-response properties.
Recurrence Methods in the Analysis of Learning Processes
Authors: Mendelson S. , Nelken I.
Published: July 2002

The goal of most learning processes is to bring a machine into a set of “correct” states. In practice, however, it may be difficult to show that the process enters this target set. We present a condition that ensures that the process visits the target set infinitely often almost surely. This condition is easy to verify and is true for many well-known learning rules.To demonstrate the utility of this method, we apply it to four types of learning processes: the perceptron, learning rules governed by continuous energy functions, the Kohonen rule, and the committee machine.
Democratic Integration: Self-Organized Integration of Adaptive Cues
Authors: Triesch Jochen , Malsburg Christoph von der
Published: July 2002

Sensory integration or sensor fusion—the integration of information from different modalities, cues, or sensors—is among the most fundamental problems of perception in biological and artificial systems. We propose a new architecture for adaptively integrating different cues in a self-organized manner. In Democratic Integration different cues agree on a result, and each cue adapts toward the result agreed on. In particular, discordant cues are quickly suppressed and recalibrated, while cues having been consistent with the result in the recent past are given a higher weight in the future. The architecture is tested in a face tracking scenario. Experiments show its robustness with respect to sudden changes in the environment as long as the changes disrupt only a minority of cues at the same time, although all cues may be disrupted at one time or another.
An On-Line Agglomerative Clustering Method for Nonstationary Data
Authors: Guedalia Isaac David , London Mickey , Werman Michael
Published: July 2002

An on-line agglomerative clustering algorithm for nonstationary data is described. Three issues are addressed. The first regards the temporal aspects of the data. The clustering of stationary data by the proposed algorithm is comparable to the other popular algorithms tested (batch and on-line). The second issue addressed is the number of clusters required to represent the data. The algorithm provides an efficient framework to determine the natural number of clusters given the scale of the problem. Finally, the proposed algorithm implicitly minimizes the local distortion, a measure that takes into account clusters with relatively small mass. In contrast, most existing on-line clustering methods assume stationarity of the data. When used to cluster nonstationary data, these methods fail to generate a good representation. Moreover, most current algorithms are computationally intensive when determining the correct number of clusters. These algorithms tend to neglect clusters of small mass due to their minimization of the global distortion (Energy).
A Metric to Quantify Virtual Scene Movement for the Study of Cybersickness: Definition, Implementation, and Verification
Authors: So Richard H. Y. , Ho Andy , Lo W. T.
Published: July 2002

This paper presents a metric to quantify visual scene movement perceived inside a virtual environment (VE) and illustrates how this method could be used in future studies to determine a cybersickness dose value to predict levels of cybersickness in VEs. Sensory conflict theories predict that cybersickness produced by a VE is a kind of visually induced motion sickness. A comprehensive review indicates that there is only one subjective measure to quantify visual stimuli presented inside a VE. A metric, referred to as spatial velocity (SV), is proposed. It combines objective measures of scene complexity and scene movement velocity. The theoretical basis for the proposed SV metric and the algorithms for its implementation are presented. Data from two previous experiments on cybersickness were reanalyzed using the metric. Results showed that increasing SV by either increasing the scene complexity or scene velocity significantly increased the rated level of cybersickness. A strong correlation between SV and the level of cybersickness was found. The use of the spatial velocity metric to predict levels of cybersickness is also discussed.
Inserting the Presence of Mind into a Philosophy of Presence: A Response to Sheridan and Mantovani and Riva
Authors: Biocca Frank
Published: July 2002

This article considers the following question: What is the best foundation for a theory of presence? After establishing criteria for a philosophy of presence, the article applies these criteria to a set of articles on the philosophy of presence by Sheridan (1999), Mantovani and Riva (1999), and others. Although we share common goals, it is suggested that these articles advance a philosophy of presence that may be ill suited to support theory and research on presence.

Several arguments are advanced to support this judgment. J. J. Gibson's work may be misinterpreted to accommodate relativistic models of physical reality. By directly referencing Gibson's writings, especially his concepts of ecological invariants, the article details how Gibson's work could not be used to support cultural, relativistic, or “engineering” arguments about “different realities”, perceptual or otherwise, without significant modification of Gibson's work and violation of his apparent intent.

Another source of problems for a philosophy of presence is traced. There appears to be a terminological and theoretical confusion about the difference between epistemology and ontology. This article proposes that ontological debates about divine presence represented by these authors may be inappropriate or sterile for three reasons: (1) although perceptual presence (that is, phenomenal states of distal attribution) and “divine presence” (that is, immanence of God) share the term presence, they are fundamentally different philosophical problems; (2) the concept of divine presence and Sheridan's associated “estimation paradigm” is framed at such a level of generality to be incapable of supporting specific, actionable, and researchable theories about perceptual presence; and (3) any theory about “virtual reality”, a technology with a misleading oxymoronic term, provides no more ontological insight into reality than does theory and research on any other communication medium such as photography, film, or sound recording.

Finally, the article proposes a remedy. The philosophy of presence might be most fruitfully approached via the philosophy of mind. Specifically, it is suggested that presence opens the door to related problems in the science of human consciousness, notably the mind-body problem. The article also suggests that the problem of presence bridges the philosophy of mind and the philosophy of technology on the issue of mediated embodiment, that is, the fuzzy boundary between the body and technological extensions of the body.
A Structured Approach to LCA Improvement Analysis
Authors: Graedel Thomas E.
Published: July 2002

The third stage of life‐cycle assessment, interpretation analysis (and improvement analysis, one of its components), has received relatively modest attention from LCA developers, especially as regards approaches for effecting improvements. However, this latter step is crucial if the LCA is to produce environmental benefits. A structured approach to improvement analysis is proposed, in which it is recognized that decisions regarding the recommendations that flow from the first two LCA stages are based not only on the environmental aspects of the recommended actions but also on such factors as technical feasibility, economic benefit, implications for product management, and effects on customer perception. A prioritization technique based on these factors is developed, as are two prioritization diagrams, one segmented by action agent and one segmented by life stage.
DEUTERONOMY 31-32 AS A TEXTUAL MEMORIAL
Authors: Britt Brian
Published: July 2002

This essay analyzes the narrative of Deuteronomy 31–32 as the alternation between two narrative strands: (1) the death of Moses and commission of Joshua, and (2) the writing and reciting of the Torah and song. This alternating structure culminates in a passage that harmonizes the two strands: 32:44-47. In light of this structure, with its emphasis on the and song, I suggest the concept of memorial, based on the text's use of the term (witness), as a heuristic description of the text.
WHAT IF ZEDEKIAH HAD REMAINED LOYAL TO HIS MASTER?
Authors: Lemche Niels Peter
Published: July 2002

This article works with two different examples of virtual history. The first describes the outcome of the events of 587 bce. What if Zedekiah had not revolted? Then there would have been no Babylonian Exile, no Judaism founded on the idea of an exile, no Christianity founded on Judaism, and no Islam. So perhaps Zedekiah's decision to revolt was the single most important decision made by any persion in the history of Western civilization. Whereas this first scenario is a mock scenario, the second is not. It concerns the virtual history constructed by the biblical historians who, among other things, created the myth of the Babylonian Exile as the foundation myth of their constructed nation, the new Israel. Seen in light of the extent of virtual history found in the Bible, the first scenario could easily—from an historian's point of view—be considered closer to the actual events in the southern Levant of the early sixth century bce.
"SHE IS NOT MY WIFE AND I AM NOT HER HUSBAND": A MATERIALIST ANALYSIS OF HOSEA 1–2
Authors: Yee Gale
Published: July 2002

This article is a materialist analysis of Hosea 1-2, involving an investigation of the eighth-century mode of production operative during Hosea's time (extrinsic analysis) and how this mode of production is ideologically embedded in Hosea's marriage metaphor for the God/Israelite relationship (intrinsic analysis). Hosea denounces a mode of production that involved a royal agribusiness and foreign policy, which exploited the peasantry, and was embodied in the public state veneration of the baals. Hosea directs his condemnation against the ruling élite, feminized in a metaphor of an adulterous wife who runs after her lovers (the foreign nations). Through this metaphor, Hosea theologically proclaims a polemical monolatry that places him in continuity with the YHWH-Alone movement that will become normative for Israel during the exilic and post-exilic periods.
MEMBERSHIP IN PRIVATE ASSOCIATIONS IN PTOLEMAIC TEBTUNIS
Authors: Muhs Brian
Published: July 2002

Certain private associations in Ptolemaic Egypt engaged in distinctly Egyptian religious activities and compiled rules in native Demotic. These rules closely parallel those written in Greek and Latin, however, and examination of several rules from Tebtunis further suggests that their associations played social roles analogous to those played by associations elsewhere in the Graeco-Roman world. Certaines associations privées en Égypte ptolémaïque se consacrent à des activités religieuses typiquement égyptiennes et établissent des règlements en démotique. Ces règlements ressemblent toutefois à ceux qui sont rédigés en langues grecque et latine et l'étude de quelques textes relatifs à Tebtunis suggère, en outre, que ces associations jouent un rôle social analogue aux rôles joués par d'autres associations ailleurs dans le monde gréco-romaine.
Phidiae Putavi Martial und der Hercules Epitrapezios des Novius Vindex
Authors: Schneider Werner
Published: July 2002

Martial introduces the sitting figure of a Hercules Epitrapezios in two epigrams of his ninth book (9. 43, 44). The first of them highlights the artistic qualities of the small statuette supposed to be of Lysippan origin. Its glory is further enhanced by the illustrious series of highborn predecessors whose table the little figurine had previously adorned. The verses of this first epigram are flamboyant in style with a strong epic colouring whereas the second epigram treats the same subject in a very different manner. The final point of this more modest piece with its allusion to Phidias remains unclear. A number of contentious explanations have been proposed, of which most fail to convince in as much as textual criticism of the passage has been unduly neglected by philologists and archaeologists. As a result of our proposal the name of the highly celebrated sculptor Phidias gives rise to a pun which makes reference to the small scale of the objet d'art.
THE REIGN OF SOLOMON IN THE MAKING: PSEUDO-CONNECTIONS BETWEEN 3 KINGDOMS AND CHRONICLES
Authors: Talshir Zipora
Published: July 2002

The unit dedicated to the reign of Solomon in the Books of Kings is composed of an extraordinary mixture of different materials, presenting an excellent example of a work in the making whose process of formation is still clearly apparent. The parallel material in the Septuagint of 3 Kingdoms, on the one hand, and in the Books of Chronicles, on the other, show major differences in comparison with the Books of Kings. This article touches on the intriguing question of whether 3 Kingdoms (LXX) and Chronicles preserve stages previous or parallel to the formation of the Books of Kings or are rather later redactions based on a version similar to the canonical version. More specifically, it is argued that there are no straightforward interrelations between the seemingly similar features reflected in 3 Kingdoms and Chronicles - contra A.G. Auld's simplistic approach to the history of Kings versus Chronicles.
SENS ET FONCTION DE GEN. XXII 14
Authors:   Marx
Published: July 2002

En rachetant son fils premier-né, Abraham manifeste sa volonté de faire de sa descendance le peuple de Yhwh. Gen. xxii 14 se rapporte aux obligations qui résultent de l'appartenance à Yhwh et singulièrement à celle faite à tous les hommes de se présenter régulièrement devant leur Seigneur.
THEONOMY AND BIOLOGY: TILLICH'S ONTOLOGY OF LOVE AS THE BASIS FOR AN ENVIRONMENTAL ETHIC
Authors: Drummy Michael
Published: July 2002

In this article, the thought of the late Protestant theologian, Paul Tillich, is considered as a resource for a contemporary environmental ethic. Tillich's ontology of love is revisited through the filter of the present global ecological crisis as a way of clarifying the various relationships that exist among the different forms of love. The paper concludes by going beyond Tillich's usage of agape love strictly as a form of love between human persons to include the non-human community within the orbit of humanity's unconditional concern for the 'other', that is, toward an ethic of 'bio-agape'.
EDIBLE BULLS AND DRINKABLE MICE: EIGHTEENTH-CENTURY TAXONOMY AND THE CRISIS OF EDEN
Authors: Mounsey Chris
Published: July 2002

In the eighteenth-century stampede to categorize and name the newly discovered flora and fauna of the world, kangaroos, platypuses and the Barbadoes wild olive trampled the classical taxonomic works of the Greek, Roman and Medieval worlds into the dust. Eden was no longer populated simply by cows, sheep, royal lions and the occasional snake. It was a dangerous place filled with rabbits the size of people, otters with a duck's bill and snails that looked like fruit. New and strange animals presented problems both for the classifiers, who fought among themselves to discover sites of taxonomic rigour, and for the religious, who, all at once, had to re-interpret the Pentateuch to take account of the fact that many more animals had avoided drowning in the universal deluge than had been hitherto thought. The latter led to an even more serious problem for the understanding of how language worked: if God had named the animals for Adam in Eden as the basis of language, what was this new deluge of species for? This paper explores how for one religious poet, Christopher Smart, the host of new species presented an ideal opportunity to put right some of the mistakes in the strictly Biblical Adamic theory of language, which had been brought to light by recent developments in Newtonian science.
THE EFFECTS OF SPATIAL CONTEXT AND SOCIAL EXPERIENCE ON THE TERRITORIAL AGGRESSION OF MALE THREESPINE STICKLEBACK
Authors: Bolyard Kimberly , Rowland William
Published: July 2002

1. Territorial male threespine stickleback, Gasterosteus aculeatus, attacked their neighbors more and escaped from their neighbors less when at their own nests than when at their neighbors' nests. In this study, attacks decreased gradually and escape attempts increased gradually as males moved from the center to the edge of their territories. 2. As predicted by the conflict hypothesis, males performed head-down threat displays most at their territory boundaries. The conflict hypothesis holds that aggression and fear are two opposing tendencies that regulate the expression of attack and escape behavior. 3. This experiment did not find evidence for a threshold effect of aggression or fear in which new behaviors would abruptly replace attack or escape once a certain level of motivation had been activated. 4. Males in our study that had social experience outside of their territories, either fighting with a rival or spending time with a sympatric heterospecific, made fewer attacks overall in later encounters with their neighbors in their and their neighbors' territories than did males without social experience. This finding demonstrates that the influence of encounter site on territorial aggression is modified by a male's past experience. 5. Males with winning and losing experiences outside of their territories did not respond differently to their neighbors in later encounters.
TRADEOFFS BETWEEN PREDATION RISK AND FEEDING IN A LIZARD, THE BROAD-HEADED SKINK (EUMECES LATICEPS)
Authors: Cooper William
Published: July 2002

Foraging, feeding, and escape decisions may all be modified by threat of predation. Field experiments using a human simulated predator show that a lizard, the broad - headed skink, Eumeces laticeps, alters several aspects of feeding behavior in ways suggesting tradeoffs between predation risk and feeding. When food (cricket) was closer to the predator, the lizards more frequently did not attack it, and often retreated to safety before consuming it, reducing the duration of exposure to predation. The probability of attacking a cricket decreased with distance of the lizard from refuge, reflecting greater risk due to increased time required to reach refuge. Latency to attack increased with distance of the lizard from refuge, suggesting that lizards assessed the risk as acceptable after observing the predator's continued immobility. Large crickets were attacked with higher probability and shorter latency than small crickets, indicating that greater risk was acceptable for greater energetic benefit. The lizards more frequently carried large than small crickets to refuges before eating them, reducing duration of exposure because handling time was greater for larger crickets. Smaller crickets were consumed where captured, again indicating modification of feeding behavior in response to predation risk. The skinks also reduced risk by reducing handling time when closer to the predator. Escape was delayed until a predator approached closer when lizards were eating than when not eating. This delay may reflect a tradeoff between predation risk and acquisition of food.
HETEROSPECIFIC RESPONSES TO SCREAM CALLS AND VOCAL MIMICRY BY PHAINOPEPLAS (PHAINOPEPLA NITENS) IN DISTRESS
Authors: Chu Miyoko
Published: July 2002

Using playback experiments, I tested whether distress calls by phainopeplas attract heterospecifics and elicit mobbing of a predator decoy. Phainopeplas use two types of distress calls: loud scream calls and mimicry of other species' vocalisations. Screams and imitations together attracted significantly more heterospecifics than in the absence of distress calls. When broadcast alone, scream calls were more effective at eliciting heterospecific approach and mobbing behaviour than were imitations. Birds were significantly more likely to mob the predator decoy during broadcast of screams and imitations than during broadcast of screams with digitally scrambled imitations, even though there was no significant difference between treatments in the number of birds initially approaching. This suggests that precise mimicry does not play a key role in attracting heterospecifics but may elicit increased mobbing once they have arrived. Mimicry did not appear to be directed at the species whose calls were imitated; only 4 of the 19 species responding to distress calls were model (mimicked) species, and birds mobbed the predator decoy regardless of whether imitations of their own calls were used in playback trials.