bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of visual tracking for robot‐assisted laparoscopic surgery
Authors: Zhang Xiaoli , Payandeh Shahram
Published: October 2002

With the increasing popularity of laparoscopic surgery, the demand for better modes of laparoscopic surgery
also increases. The current laparoscopic surgery mode requires an assistant to hold and manipulate the endoscope
through commands from the surgeon. However, during lengthy surgery procedures, accurate and on‐time
adjustment of the camera cannot be guaranteed due to the fatigue and hand trembling of the camera assistant.
This article proposes a practical visual tracking method to achieve automated instrument localization and
endoscope maneuvering in robot‐assisted laparoscopic surgery. Solutions concerning this approach, such
as, endoscope calibration, marker design, distortion correction, and endoscope manipulator design are described
in detail. Experimental results are presented to show the feasibility of the proposed method. © 2002 Wiley
Periodicals, Inc.
Implications of flood pulse restoration for populus regeneration on the upper Missouri River
Authors: Bovee Ken D. , Scott Michael L.
Published: October 2002

We developed a mass balance flow model to reconstruct unregulated daily peak flows in the National Wild and Scenic reach of the Missouri River, Montana. Results indicated that although the observed frequency of large peak flows has not changed in the post‐dam period, their magnitude has been reduced from 40 to 50% as a consequence of flow regulation. Reductions in the magnitude of these flows should reduce the expected frequency of large flood‐pulses over a longer time‐scale. Results of a two‐dimensional hydraulic model indicated that limited cottonwood (Populus deltoides subsp. Monilifera) recruitment occurs at relatively small peak discharges, but to maximize establishment of cottonwoods in the Wild and Scenic reach, a threshold of 1850 m3/s would be necessary at the Virgelle gauge. Floods of this magnitude or greater lead to establishment of cottonwood seedlings above the zone of frequent ice‐drive disturbance. Restoring the frequency, magnitude, duration and timing of these flood pulses would benefit important natural resource values including riparian cottonwood forests and native fish species in the upper Missouri River basin. However, efforts to naturalize flow must be made in the context of a water management system that was authorized and constructed for the primary purposes of flood control, power generation and irrigation. Using the synthesized flow model and flood damage curves, we examined six scenarios for delivering flows ≥1850 m3/s to the Wild and Scenic reach. Whereas some scenarios appeared to be politically and economically infeasible, our analysis suggested that there is enough operational flexibility in the system to restore more natural flood pulses without greatly compromising other values. Published in 2002 by John Wiley & Sons, Ltd.
The emphasis given to evolution in state science standards: A lever for change in evolution education?
Authors: Skoog Gerald , Bilica Kimberly
Published: October 2002

This study analyzed the science frameworks of 49 states and the District of Colombia to determine the emphasis given to evolution in these documents at the middle and secondary levels. These concepts were species evolve over time, speciation, diversity of life, descent with modification from common ancestry, evidence of evolution, natural selection, pace and direction of evolution, and human evolution. Collectively, the 50 science frameworks emphasized evolution in a manner that suggests that if the public's support for standards‐based curricula is a reality, the study of evolution will be emphasized in an unprecedented manner in the nation's schools in the near future. However, all concepts were not emphasized equally in these documents. For example, human evolution was included in only seven documents. The word evolution is absent from some standards. Despite these negatives, recent actions to improve existing standards or to adopt new standards that emphasize evolution have occurred. The metaphor “lever of change” is often used in the context of school reform. This metaphor suggests a simple system where one change can result in a desired outcome. However, in classrooms where curriculum decisions evolve constantly, multiple factors interact and reinforce one another in response to both internal and external contingencies that emerge. Educational change can not be reduced to a simple linear cause/effect situation. The change process involved is nonlinear where what goes in is not proportional to what comes out because of feedback loops and other factors that complicate results. This nonlinearity is reflected in the varied responses of teachers to specific contingencies. Yet, systems can be changed and nudged towards a structure where desired outcomes will emerge. Judicial rulings indicating that the teaching of evolution cannot be prohibited or equal time for creationism mandated, improved coverage of evolution in secondary school biology textbooks, the negative response of many leaders, scientists, organizations, and editorial writers to the 1999 decision of the Kansas State Board of Education to deemphasize and misrepresent evolution in the state's science standards, and the emphasis given to evolution in the standards reviewed for this study, all coalesce to provide needed support for administrators and teachers who are striving to create science curricula that emphasize evolution in a manner commensurate with its importance in understanding the natural world and our place within it. © 2002 Wiley Periodicals, Inc. Sci Ed 86:445–462, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/sce.10014
Definition of a similarity measure between cases based on auto/cross‐fuzzy thesauri
Authors: Nomoto Kohei , Kise Wakasa , Kosuge Yoshio
Published: October 2002

A similarity measure between cases is needed in order to evaluate the degree of similarity when using past similar cases in order to resolve current problems. In similar case retrieval, multiple indices are set up in order to characterize the queries and individual cases, then terms are given as values to each. The similarity measure between cases commonly used is defined using the rate at which the values provided from the corresponding indices match. In practice, however, values cannot be expected to be mutually exclusive. As a result, a natural expansion of this approach is to have relationships in which mutually similar meanings are reflected in the similarity measure between cases. In this paper the authors consider an auto‐fuzzy thesaurus which gives the relationship for values between corresponding indices and a cross‐fuzzy thesaurus which gives the relationship for values between mutually distinct indices, then defines a similarity measure between cases which considers the relationship of index values based on these thesauri. This definition satisfies the characteristics required for the operation of case‐based retrieval even when one value is not necessarily given in the index. Finally, using a test similar case retrieval system, the authors perform a comparative analysis of the proposed similarity measure between cases and a conventional approach. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(9): 99–108, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.1156
An interaction mechanism of multimodal dialogue systems
Authors: Takahashi Kazuko , Takezawa Toshiyuki
Published: October 2002

We propose a mechanism to handle ellipsis/anaphora resolution effectively for a dialogue system with multimodal interfaces. This mechanism uses a new method of storing/searching through the history of a dialogue. We express the object referred to by the current utterance as the packed data of all the related terms appearing in the preceding utterances. We formalize the mechanism and present an evaluation of a multimodal guidance system that has this mechanism. Experimental results show that this mechanism achieves natural dialogue with high interaction. We also discuss a method of evaluating interactive spoken dialogue systems. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(11): 70–79, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.1165
Precise object pose estimation in range image considering measurement error
Authors: Okatani Ikuko Shimizu , Deguchi Koichiro
Published: October 2002

In this paper, we describe a method for estimating the position and pose of an object from its range image when its shape model is given. The measurement errors of the range image in the viewing direction are much larger than those in the directions parallel to the image plane and their magnitudes differ at every measurement point. We estimate the precise position and pose by considering these characteristics. The observed shape under consideration obtained discretely as a range image is regarded as a plane locally and expressed by a set of triangular patches. On the other hand, the model is expressed by a set of points. The respective points of the model are regarded originally on their corresponding triangular patch plane. The gaps between the model points and their corresponding triangular patches are considered as caused by the measurement errors. Its possibility of occurrence is called the matching value and the goodness of the registration of the set of triangular patches to the set of model points is expressed by the sum of the square of these matching values at the respective model points. The distribution of these matching values in the space is called the matching map. The coordinate transformation in the space the best match is determined by moving the model points in the space. For this purpose, to evaluate the goodness of the registration by the coordinate transformation, the gradient of the matching map is directly calculated. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(11): 107–116, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.1168
Quantitative AES depth profiling of a Ge/Si multilayer structure
Authors: Hofmann Siegfried , Kesler Valeri
Published: October 2002

Auger electron spectroscopy (AES) depth profiling of a Ge/Si multilayer structure with Ge layers of 2.2, 4.3 and 2.2 nm thickness in Si was performed with Ar+ ions of 1.5 and 3 keV energy and at 74° incidence angle to the normal to the surface. The plot of the Ge LMM Auger peak intensity as a function of the sputtering time was analysed quantitatively using the MRI (mixing–roughness–information depth) model. As a result, the optimum MRI parameters w (mixing length), σ (roughness) and λ (here, used as information depth) were found to be 1.7, 0.8 and 1.6 nm, respectively, for 1.5 keV Ar+ bombardment. For an appropriate evaluation of the 3 keV Ar+ data, w had to be increased to 3.0 nm and σ to 1.4 nm, respectively, while λ was kept constant. In the first run, the MRI calculation results could not be fitted optimally to the profiling results, and therefore the assumed in‐depth distribution of Ge had to be changed accordingly. After a few modifications of the latter and of the roughness parameter, an optimized fit was obtained by changing either the thickness of the layers or the average Ge concentration within the layers, or, most favourably, by a combination of both approaches. Comparison with densitometer measurements on transmission electron microscopy images confirm the thicker layer structure. Copyright © 2002 John Wiley & Sons, Ltd.
Depth profile analysis of ion‐implanted photoresist by infrared spectroscopy
Authors: Nagai N. , Imai T. , Terada K. , Seki H. , Okumura H. , Fujino H. , Yamamoto T. , Nishiyama I. , Hatta A.
Published: October 2002

Structural distribution at different depths in a novolac photoresist after boron ion implantation was analysed using infrared spectroscopy with gradient shaving preparations and spectral simulation techniques. The generation of graphite‐like structures and B–O and/or B–C bonding was observed only near the surface at approximately ∼0.1 µm for a sample that was ion implanted at 10 keV acceleration voltage and at ∼0.2 µm for a sample ion implanted at 100 keV. The main chemical change appears to be bond‐breaking (namely, the generation of voids) in inner films. In the process of mechanical shaving, the peel strength, degree of adhesion and shear strength were determined. Decreases in peel strength and degree of adhesion after ion implantation are thought to be primarily the result of bond‐breaking. The method described in this paper is effective for studying chemical bonding changes with depth and would be of help in understanding mechanical strength from the viewpoint of chemical bonding. Copyright © 2002 John Wiley & Sons, Ltd.
Surface physico‐chemistry of corona‐discharge‐treated poly(ethylene terephthalate) film
Authors: O'Hare Lesley‐Ann , Smith Julie A. , Leadley Stuart R. , Parbhoo Bhukan , Goodwin Andrew J. , Watts John F.
Published: October 2002

The effect of energy of corona discharge treatment (CDT) on the physico‐chemistry of the surface of a polyester film was investigated systematically using a number of complementary surface analytical techniques: contact angle analysis, x‐ray photoelectron spectroscopy, time‐of‐flight secondary ion mass spectrometry and atomic force microscopy. The energy of treatment can be controlled by either varying the speed of the treatment with constant power input or by varying the power of the treatment with constant speed. The changes in surface energy, surface chemistry and surface morphology of poly(ethylene terephthalate) (PET) induced by these two modes of CDT have been investigated.

The surface energy and the polar contribution of the film increased with increasing energy of corona. Phenolic‐OH, carbonyl and carboxylic acid (HOC=O) have been identified as the functional groups incorporated onto the surface. Low‐molecular‐weight oxidized materials were observed in the form of a globular morphology on the surface of the film. By washing the film in methanol–water prior to surface analysis, it was shown that the oxygen content at the surface of the film decreased and the globular morphology was removed.

Differences in the surface energy of corona‐treated PET films have been observed under similar corona energy conditions, depending on whether the sample was treated with constant speed or constant power. However, the total surface oxygen content was found to be similar at low‐energy treatments. When the high‐resolution C 1s XPS spectrum was peak fitted, the relative concentrations of functional groups introduced and other changes to the original polymer structure were shown to be independent of the mode of treatment.

These observations may be explained because although the total energy transferred from the power source to the PET under the conditions of ‘constant power, variable speed’ and ‘variable power, constant speed’ is theoretically the same, these experimental conditions are not interchangeable. At constant power, the concentration of active species, radiation and dielectric breakdowns in the discharge are independent of speed. However, in the case of constant speed, the concentration of active species, radiation and dielectric breakdown increase with increasing power, resulting in a different surface energy between the two sets of samples. However, because the composition of the active species will not change, the functional groups on the surface of the film will be the same across comparable energy levels, independent of mode of treatment. Copyright © 2002 John Wiley & Sons, Ltd.
Estimation of the time‐dependent vaccine efficacy from a measles epidemic
Authors: Eichner M. , Diebner H. H. , Schubert C. , Kreth H. W. , Dietz K.
Published: October 2002

We present a method to estimate the time‐dependent vaccine efficacy from the cohort‐specific vaccination coverage and from data on the vaccination status of cases and apply it to a measles epidemic in Germany which involved 529 cases, 88 of whom were vaccinated and 370 unvaccinated (for the remaining 71 cases the vaccination status is unknown). Our epidemiological model takes into account that maternal antibodies prevent successful vaccination and that vaccine immunity may be lost over time. Model parameters are estimated from the data using maximum likelihood. Vaccination coverage, as determined in school surveys, ranged from 27.6 per cent for the cohort born in 1974 to 85 per cent for the 1986 cohort, which is far too low to prevent measles transmission. Cohorts for which no school surveys were performed are omitted from analysis. Thus, sufficient data are available for only 282 cases, 69 of whom are vaccinated. According to our estimates, measles vaccinations provided no immunity before 1978 (95 per cent CI: 0 to 47 per cent), for the period 1978‐1982, the estimated vaccine efficacy was 80per cent (95 per cent CI: 67 to 89 per cent), and for 1982–1990 it was 97 per cent (95 per cent CI: 93 to 99 per cent). After 1990, the estimated value dropped to 89 per cent, but its confidence interval widely overlaps with that of the previous period (95 per cent CI: 74 to 97 per cent). Loss of immunity was estimated to be zero (95 per cent CI: 0 to 0.003/year). Several sensitivity analyses were performed with respect to the model assumptions. A modified model which assumed constant efficacy at all vaccination times yielded a high estimate of 96 per cent (95 per cent CI: 92 to 98 per cent) for primary vaccine efficacy but also a high loss rate of immunity of 0.007/year (95 per cent CI: 0.001 to 0.012) to explain the high fraction of vaccinated cases among older individuals. The likelihood score value is however significantly inferior compared to the score value of the model with time‐dependent vaccine efficacy. Copyright © 2002 John Wiley & Sons, Ltd.
Taming access control security: extending capabilities using the views relationship
Authors: Markiewicz Marcus E. , Lucena Carlos J. P. , Cowan Donald D.
Published: October 2002

The ‘views’ relationship indicates how an object‐oriented design can be clearly separated into objects and their corresponding interface. This paper uses the concept of ‘views’ in order to achieve full separation between the application and the security policy in the design and implementation. The result is achieved by providing a model for capabilities using ‘views’ that is richer than the traditional capability model. In addition, a distributed access control model is shown to be effective through the use of Secure Object Communication Channels (SOCCs) to allow for secure connections at the abstract object level. This security is applicable in the e‐commerce application domain, bringing security directly to the application abstraction level. Copyright © 2002 John Wiley & Sons, Ltd.
Java 3D, 3D graphical environments and behaviour
Authors: Burrows Anthony L. , England David
Published: October 2002

A brief outline of the structure of the Java 3D API as a means of producing graphical environments is provided. We then go on to examine issues in the development of a behaviour rich scene, in particular the issues of scene animation and collisions between scene objects. The animation issue is examined first, where issues of timing and architecture are considered. The Java 3D requirements for, and view of, collision are discussed next from a general perspective, identifying several problems with the implementation. Four simple scenes using animation and collision detection are examined. In each case a number of difficulties have been identified, partly related to the responsiveness of the operating system in the case of animation, but particularly due to the view and implementation of the collision detection system provided. Collisions often involve modifications to the states of all objects involved in the collision and some of the issues this raises in the context of Java 3D's provision are examined and reported on. Finally, we finish with a summary of our findings and conclusions on the suitability of Java 3D for building environments. Copyright © 2002 John Wiley & Sons, Ltd.
MEADOW: a middleware for efficient access to multiple geographic databases through OpenGIS wrappers
Authors: Cha Sang K. , Kim Kihong , Lee Byung S. , Song Changbin , Hwang Sangyong , Kwon Yongsik
Published: October 2002

With the proliferation of various geographic databases on the Internet, we have seen increasing needs for accessing them concurrently and remotely via the Web for high‐level decision making. In this paper, we present Middleware for Efficient Access to Databases through OpenGIS Wrappers (MEADOW), an object‐oriented middleware system we have developed to meet these needs. Current OpenGIS standard addresses many interoperability issues involved in such a global utilization of geographic databases. However, existing Simple Feature specification for CORBA (SFCORBA) implementations of OpenGIS proved to be insufficient for MEADOW. The main problems are the complexity of system development and maintenance, and the inefficiency of accessing remote data servers for processing region queries. We resolved the complexity problem by automatically generating a major portion of the application code, specifically wrappers on database servers and client library modules called transparent access providers. A MEADOW view definition language was developed as a high‐level specification language for this purpose. The efficiency problem was resolved by using a region‐based group prefetching of spatial objects from a geographic region. In addition, we implemented an OID‐based semijoin for efficient global query processing, and a region‐level locking to enhance the level of concurrency among region queries. Copyright © 2002 John Wiley & Sons, Ltd
Data collection and restoration for heterogeneous process migration
Authors: Chanchio Kasidit , Sun Xian‐He
Published: October 2002

This study presents a practical solution for data collection and restoration to migrate a process written in high‐level stack‐based languages such as C and Fortran over a network of heterogeneous computers. We first introduce a logical data model, namely the Memory Space Representation (MSR) model, to recognize complex data structures in process address space. Then, novel methods are developed to incorporate the MSR model into a process, and to collect and restore data efficiently. We have implemented prototype software and performed experiments on different programs. Experimental and analytical results show that: (1) a user‐level process can be migrated across different computing platforms; (2) semantic information of data structures in the process's memory space can be correctly collected and restored; (3) costs of data collection and restoration depend on the complexity of the MSR graph in the memory space and the amount of data involved; and (4) the implantation of the MSR model into the process is not a decisive factor of incurring execution overheads. With appropriate program analysis, we can practically achieve low overhead. Copyright © 2002 John Wiley & Sons, Ltd.
The BLISS programming language: a history
Authors: Brender Ronald F.
Published: October 2002

The BLISS programming language was invented by William A. Wulf and others at Carnegie‐Mellon University in 1969, originally for the DEC PDP‐10. BLISS‐10 caught the interest of Ronald F. Brender of DEC (Digital Equipment Corporation). After several years of collaboration, including the creation of BLISS‐11 for the PDP‐11, BLISS was adopted as DEC's implementation language for use on its new line of VAX computers in 1975. DEC developed a completely new generation of BLISSs for the VAX, PDP‐10 and PDP‐11, which became widely used at DEC during the 1970s and 1980s. With the creation of the Alpha architecture in the early 1990s, BLISS was extended again, in both 32‐ and 64‐bit flavors. BLISS support for the Intel IA‐32 architecture was introduced in 1995 and IA‐64 support is now in progress.

BLISS has a number of unusual characteristics: it is typeless, requires use of an explicit contents of operator (written as a period or ‘dot’), takes an algorithmic approach to data structure definition, has no goto, is an expression language, and has an unusually rich compile‐time language.

This paper reviews the evolution and use of BLISS over its three decade lifetime. Emphasis is on how the language evolved to facilitate portable programming while retaining its initial highly machine‐specific character. Finally, the success of its characteristics are assessed. Copyright © 2002 John Wiley & Sons, Ltd.
The art and practical wisdom of student affairs leadership
Authors: Dalton Jon C.
Published: October 2002

The author argues that practical wisdom is the highest achievement of professional practice and examines how practical wisdom is gained and nurtured in professional life.
Case study of testing a distributed internet‐system
Authors: Goeschl Siegfried , Sneed Harry M.
Published: October 2002

This paper describes the testing strategy, methods and tools used for testing a distributed financial services system on the Internet with CORBA interfaces for handling a high volume of queries to a relational database. The new system architecture was derived by reengineering a previous more limited application. The paper starts with an outline of the software architecture, the testing requirements and the testing strategy. It then goes on to describe the tools used in the project and the results achieved. For the project a generic C++ integration test framework was developed especially for testing distributed components. This tool is described in detail. The paper ends with a discussion of the discovered defects and their distribution. Copyright © 2002 John Wiley & Sons, Ltd.
Intravenous self‐administration of amphetamine is increased in a rat model of depression
Authors: Holmes Philip V. , Masini Cher V. , Primeaux Stefany D. , Garrett Joshua L. , Zellner Andrew , Stogner Kimberly S. , Duncan Alicia A. , Crystal Jonathon D.
Published: October 2002

Affective disorders and substance abuse frequently coexist, yet few previous studies have examined drug self‐administration using animal models of depression. The olfactory‐bulbectomized rat is a well‐established model that exhibits a high degree of neurochemical similarity to depression. Olfactory bulbectomy (OBX) increases dopamine receptor densities in the ventral striatum, which may increase the reinforcing effects of drugs of abuse. Experiments were designed to test the hypotheses that acquisition and stable self‐administration of amphetamine would be increased in bulbectomized rats. In the first experiment, rats underwent bilateral OBX or sham surgery and intravenous jugular catheters were implanted 12–14 days later. Acquisition was examined using a standard operant paradigm involving a nose‐poke response for a very low dose of D‐amphetamine sulfate (12 μg/infusion, IV). A separate group of rats received coinfusions of sulpiride. In a second experiment designed to minimize differences in acquisition and examine stable self‐administration, lever pressing for a low (0.10 mg/kg, IV) or high (0.25 mg/kg, IV) dose of D‐amphetamine sulfate was measured in rats pretrained to lever press for food. Bulbectomized rats acquired the self‐administration of very low dose amphetamine faster than sham‐operated rats and this effect was reversed by sulpiride coinfusion. Stable self‐administration of the low dose of amphetamine was also markedly increased in bulbectomized rats. The findings reveal the utility of the OBX model for studying the neurobiological basis of depression and drug abuse comorbidity and support the hypothesis that neurochemical abnormalities associated with depression may enhance the addictive properties of some drugs of abuse. Synapse 46:4–10, 2002. © 2002 Wiley‐Liss, Inc.
When genres meet: Inquiry into a sixth‐grade urban science class
Authors: Varelas Maria , Becker Joe , Luster Barbara , Wenzel Stacy
Published: October 2002

In this study, we explore oral and written work (plays and rap songs) of students in a sixth‐grade all African‐American urban science class to reveal ways affective and social aspects are intertwined with students' cognition. We interpret students' work in terms of the meeting of various genres brought by the students and teachers to the classroom. Students bring youth genres, classroom genres that they have constructed from previous schooling, and perhaps their own science genres. Teachers bring their favored classroom and science genres. We show how students' affective reactions were an integral part of their constructed scientific knowledge. Their knowledge building emerged as a social process involving a range of transactions among students and between students and teacher, some transactions being relatively smooth and others having more friction. Along with their developing science genre, students portrayed elements of classroom genres that did not exist in the classroom genre that the teacher sought to bring to the class. Students' work offered us a glimpse of students' interpretations of gender dynamics in their classrooms. Gender also was related to the particular ways that students in that class included disagreement in their developing science genre. © 2002 Wiley Periodicals, Inc. J Res Sci Teach 39: 579–605, 2002
Constructive texturing based on hypervolume modeling
Authors: Schmitt B. , Pasko A. , Adzhiev V. , Schlick C.
Published: October 2002

The concept of solid texturing is extended in two directions: constructive modeling of space partitions for texturing and modeling of multidimensional textured objects called hypervolumes. A hypervolume is considered as a point set with attributes of both physical (density, temperature, etc.) and photometric (color, transparency, diffuse and specular reflections, etc.) nature. The point set geometry and attributes are modeled independently using real‐valued scalar functions of several variables. Each real‐valued function defining geometry or an attribute is evaluated at the given point by a procedure traversing a constructive tree structure with primitives in the leaves and operations in the nodes of the tree. This approach provides a framework for modeling, texturing and visualization of 3D solids, time‐dependent and multidimensional objects in a completely uniform manner. We introduced a special modeling language and implemented software tools supporting the proposed approach. The concept of constructive hypervolume textures is independent of the geometry representation. We provide examples of textured Frep and BRep objects as illustrations. Copyright © 2002 John Wiley & Sons, Ltd.
Duiker food selection: Palatability trials using natural foods in the Ituri Forest, Democratic Republic of Congo
Authors: Molloy Lisa , Hart John A.
Published: October 2002

Cafeteria‐style palatability feeding trials were conducted with captive duikers in the Ituri Forest, Democratic Republic of Congo. Blue duikers (Cephalophus monticola; n = 3), and white‐bellied duikers (C. leucogaster; n = 3), were offered unlimited amounts of paired foods in two experiments consisting of 20 feeding trials each. Five different foods, including fruits and flowers common to duiker diets, were used in each experiment. Preferred foods were determined by the quantities of foods consumed and ranked using the Bradley‐Terry model for preference data. Chemical composition, including fiber fractions, protein, and soluble carbohydrates, was determined for foods offered. Blue duikers made consistent food choices in both experiments, whereas white‐bellied duikers displayed consistent preferences in Experiment 2. The choices by the white‐bellied duiker in Experiment 1 were not consistent and appeared to vary at random. The two duiker species had different food preference rankings in Experiment 1, but similar rankings in Experiment 2. The number of times a food was preferred was correlated with the amount of food consumed in both experiments for the white‐bellied duiker and only in Experiment 2 for the blue duiker. Food rankings were not significantly correlated with the chemical constituents assayed, or the size or shape of the food. For blue duikers, consumption in Experiment 1 and Bradley‐Terry rank preference in Experiment 2 were significantly correlated with food color. In summary, duiker selection of natural foods appears to be based on a variety of factors, and is not limited to chemical composition or physical characteristics. Zoo Biol 21:149–159, 2002. © 2002 Wiley‐Liss, Inc.
Effects of hand‐rearing on the reproductive success of western lowland gorillas in North America
Authors: Ryan Sadie , Thompson Steven D. , Roth Amber M. , Gold Kenneth C.
Published: October 2002

This study sought to assess the potential effects of hand‐rearing by evaluating the relationships among rearing type and reproductive success in the American Zoo and Aquarium Association's Species Survival Plan® for western lowland gorillas. Our study included data on 697 gorillas: 257 wild‐born (WB) and 440 born at zoos or related facilities in North America. We found no significant differences in the number of reproductive zoo‐born (ZB) and WB females, but more WB males sired infants than their ZB counterparts. This was influenced by a skew in the number of reproductive years for WB males in the studbook. ZB males showed no difference in infants produced per reproductive year, as compared to WB males, while ZB females produced more infants per reproductive year than did WB females. Mother‐reared (MR), ZB females produced more offspring and used more reproductive opportunity than hand‐reared (HR) females, whereas rearing had no effect on the reproductive success of ZB males. Moreover, MR and partially hand‐reared (PHR) females were more likely to become nurturing mothers themselves. Zoo Biol 21:389–401, 2002. © 2002 Wiley‐Liss, Inc.
Effect of benzo(a)pyrene and methyl(acetoxymethyl) nitrosamine on thymidine uptake and induction of aryl hydrocarbon hydroxylase activity in human fetal oesophageal cells in culture.
Authors: Chakradeo P. P. , Kayal J. J. , Bhide S. V.
Published: October 2002

Primary cultures of human fetal oesophageal cells were set up and maintained for 45 days. Epithelial cells were the dominant cell type in the culture for the first four weeks. Thereafter, both epithelial cells and fibroblasts were seen with the fibroblasts becoming the dominant cell type by the 6th week and until the cultures degenerated. The tritiated thymidine uptake showed an upward trend from day 10 up to day 30, with peak uptake at day 30 in the untreated, B(a)P treated and OAc treated cultures and decreased thereafter. The thymidine uptake levels were significantly higher in the B(a)P treated cultures when compared with levels in the untreated cultures. A concurrent increase/decrease was also seen in the cell number in all the three groups of cultures. Cultures with B(a)P and DMN‐OAc showed significantly higher AHH levels as compared with untreated cultures. These results indicate that the human fetal oesophageal cells could be viably maintained under in vitro conditions for long periods of time and also showed capacity to metabolise the carcinogens through aryl hydrocarbon hydroxylase activity.
In vitro studies on chemoprotective effect of purnark against benzo(a)pyrene‐induced chromosomal damage in human lymphocytes.
Authors: Ghaisas S. D. , Bhide S. V.
Published: October 2002

Human lymphocytes were used as an assay system to test chemopreventive activity of natural products. Purnark, a mixture of extracts of turmeric, betel leaf and catechu, was tested for its chemoprotective activity against BP induced DNA damage. Sister chromatid exchange and micronuclei were used as markers to assess the protective activity of Purnark. Purnark gave 50‐60 % protection against BP induced SCEs and micronuclei. Purnark at 1000μg dose did not show any genotoxicity.
Effect of hyaluronan on the elastase‐type activity of human skin fibroblasts.
Authors: Bernard Emmanuelle , Hornebeck William , Robert Ladislas
Published: October 2002

The influence of hyaluronan (HA) on the expression of human skin fibroblast elastase‐type protease (HSFEp) (Homsy et al, 1988) was studied. At confluency of HSF cultures, hyaluronan increased the level of HSFEp in a time and dose‐dependent fashion, Optimal effect was observed after 48 h of culture and at 2 mg/ml HA concentration; the stimulatory, effect of HA could be suppressed by 1 μM cycloheximide. The enhancement of enzyme biosynthesis by HA was dependent on cell proliferation but quasi invariant with HSF passage number (from 7‐21).
Choline acetyltransferase immunoreactivity in the human vestibular end‐organs
Authors: Ishiyama Akira , Lopez Ivan , Wackym Phillip A.
Published: October 2002

Acetylcholine (ACh) is believed to play a major role in the efferent vestibular system in several animal models, however no information regarding the role of ACh in the human efferent vestibular system has been published. Post‐embedding immunohistochemistry in a hydrophilic resin was used to investigate the choline acetyltransferase immunoreactivity (ChATi) and acetylcholinesterase (ACHE) histochemistry in human vestibular end‐organs. ChATi and AChE activity was found in numerous bouton‐type terminals at the basal area of the vestibular hair cells. These terminals were found to contact type II vestibular hair cells and the afferent chalices surrounding type I hair cells. This study provides the first evidence that the human efferent vestibular axons and terminals are cholinergic.
Behaviour of dissociated hypoblast cells on the basal lamina and on extracellular fibrils in the gastrulating chicken embryo.
Authors: Andries Luc , Harrisson Fernand , Vakaet Lucien
Published: October 2002

The spreading behaviour of dissociated hypoblast cells on and besides a band of aligned fibrils associated with the basal lamina of the epiblast was investigated by the use of scanning electron microscopy. A horse‐shaped band of aligned fibrils, first demonstrated by Wakely and England (1979), is present during the gastrulation stages of chicken embryos on the ventral side of the epiblast at the cranial and lateral borders of the area pellucida. The basal lamina of the area pellucida situated inside the fibrillar band enables the spreading and probably the locomotion of dissociated cells, which appeared as polarized cells. Numerous cells were also found on the fibrillar band, and these cells lacked distinct lamellae and a polarized shape. Extensions of the cells contacted the extracellular fibrils and, at these sites of contact, the pattern of the fibrils was frequently deformed. From these observations and from previous results emerged the concept that spreading and locomotion of dissociated hypoblast cells, as well as single mesoblast cells and healing hypoblast epithelium, are inhibited by the band of extracellular fibrils, which acts as a physical barrier. The cell biological basis of the mechanism by which extracellular fibrils associated with the basal lamina arrest the migration of hypoblast and mesoblast cells, but guide the migration of primordial germ cells, is discussed.
Cycle delay in irradiated cytochalasin‐induced polykaryons. Does cytoskeleton status affect cell cycle checkpoints?
Authors: Davies H. E. , Court J. B.
Published: October 2002

Following exposure of CHO‐K1 cells to137Cs irradiation at doses up to 20Gy, a delay in G2 was observed to occur in cells permitted to divide normally, while cells induced to become giants by means of cytochalasin B demonstrated a minimal delay in the transition 2C–8C suggesting that the inhibition of cytokinesis results in modification of one or more cell cycle checkpoints. We postulate that this may occur as a consequence of damage tolerance, or by a feedback loop resulting from the reorganisation of the cytoskeleton that precludes cytokinesis.
Effects of K+‐induced depolarization and purinergic receptor activation on elemental content in insulin‐producing RINm5F‐cells.
Authors: Pålsgård Eva , Lindh Ulf , Juntti‐Berggren Lisa , Berggren Per‐Olof , Roomans Godfried M.
Published: October 2002

X‐ray microanalysis was used to detect elemental changes in the insulin‐producing tumor cell‐line RINm5F. To improve discrimination between mobile ions and ions bound to macromolecules a new approach was employed, consisting of multivariate statistical analysis of correlations between the concentrations of Na, Mg, P, S, Cl, K, and Ca. RINm5F cells, cultured on Formvar‐coated titanium grids, were stimulated with high K+ or ATP, that are both known to stimulate insulin release. The buffers used contained Ca2+ or one of the Ca2+‐analogues Sr2+ and Ba2+, to represent Ca2+ uptake in response to stimulation. After stimulation the cells were shock‐frozen and freeze‐dried overnight. Incubation for 10‐20 seconds in a Ca2+‐containing buffer did not significantly affect elemental composition, whereas cellular Mg, P and K decreased in a Sr2+‐containing buffer. Depolarization with high K+ concentration caused an increase in the cellular Na content, both in Ca2+‐ and Sr2+‐containing buffers, but not in the buffer where Ca2+ had been replaced by Ba2+. X‐ray microanalysis is useful for detection of elemental changes subsequent to stimulation of cultured cells. Moreover, multivariate statistical analysis strengthens the idea that stimulation of RINm5F cells causes redistribution of ions possibly due to changes in the state of binding of some elements to cellular proteins.
Distribution of fibronectin in foetal tissues.
Authors: Trebichavsky Ilja , Nyklicek Otakar
Published: October 2002

The distribution of fibronectin in tissues of four human foetuses (7‐14 gestation weeks/GW) and twenty seven pig foetuses (25‐114 days of gestation) was investigated using immunofluorescence and avidin/biotin methods. Fibronectin was abundant in the circulatory and gastrointestinal system and its derivates, in reticular stroma of immune organs, and in connective tissues and chorionic villi at all developmental stages.
Dye‐coupling between term pregnant human myometrial cells before labor: Carboxyfluorescein versus lucifer yellow
Authors: Çiray H. Nadir , Persson Bo‐Eric , Roomans Godfried M. , Ulmsten Ulf
Published: October 2002

Term pregnant human myometrial cells in whole mounts were microinjected by pressure with the fluorescent probes Lucifer Yellow and carboxyfluorescein. Tissues obtained from acute and elective sections displayed weak dye‐coupling when injected with Lucifer Yellow. Injection of carboxyfluorescein into cells from the elective sections resulted in a more extensive dye‐coupling than that observed with Lucifer Yellow. These results indicate that term pregnant human myometrial cells are metabolically coupled before labor and carboxyfluorescein is superior to Lucifer Yellow in detecting the coupling.
Asymmetric cell division in human leukemic promyelocytic cells (HL‐60).
Authors: Matsuhisa Tadao
Published: October 2002

Small cells accounted for 8‐9% of the human leukemic promyelocytic cells (HL‐60). The diameter of the small cells was 8.44 μm, whereas that of the large cells, which were heterogeneous in cell size, was 11.0 μm. The small cells were produced from the large cells through asymmetric cell division, which was demonstrated by cloning experiments and by microscopy.
Combined application of in vivo UV‐crosslinking and in vitro label transfer in the examination of AU‐rich sequence binding protein ‐ RNA interactions.
Authors: Henics Tamás , Nagy Eszter , Rigby William F. C.
Published: October 2002

A combination of in vivo UV light‐induced crosslinking of nucleic acids to proteins and in vitro label transfer assay was applied to investigate specific interactions between AU‐rich sequences (ARE) in the 3′ UTR of lymphokine mRNAs and cytoplasmic AU‐rich sequence element binding proteins (AUBP) in normal human lymphoblasts and MLA 144 gibbon lymphoid tumor cells. We demonstrate that a pool of cytoplasmic AUBP can be effectively crosslinked to RNA in vivo, suggesting a close association of these proteins with ARE sequences in the cytoplasm. We also show that the UV‐crosslinked AUBP pool is markedly reduced in malignantly transformed MLA 144 cells compared with normal lymphoblasts, indicating weaker interaction between lymphokine ARE and AUBP in these tumor cells. Similar differences in AUBP‐RNA associations were found between the membrane‐bound polysomal subfractions of the two cell types where most of the AUBP activity was localized. We suggest that the decreased AUBP‐mRNA association in MLA 144 cells might reflect a process concerned with disturbances of mRNA metabolism in the neoplastic phenotype.
KERATINS AND SKIN DISORDERS
Authors: RAO SRIDHAR K. , BABU RAJA K. K. , GUPTA P. D.
Published: October 2002

The epidermal keratinocytes express two major pairs of keratin polypeptides. One pair (K5/K14) expressed specifically in basal generative compartment and the other (K1/K10) expressed specifically in the differentiating suprabasal compartment. The switch in the expression of the keratins from proliferating to differentiating compartment indicates the changes that occur in the keratin filament organization which in turn influences the functional properties of the epidermis. Proper regulation of keratin gene expression and the filament organization are absolutely necessary for normal functioning of the skin. Keratin gene mutations can influence the filament integrity thereby causing several heritable blistering disorders of the skin such as epidermolysis bullosa, bullous icthyosiform erythroderma, etc. Changes in the keratin gene expression may lead to incomplete differentiation of the epidermal keratinocyte, causing hyperproliferative diseases of the skin such as psoriasis, carcinomas, etc. This review briefly describes the changes in keratin structure or gene expression that are known to result in various disorders of the skin.
PLANT MITOSIS PROMOTING FACTOR DISASSEMBLES THE MICROTUBULE PREPROPHASE BAND AND ACCELERATES PROPHASE PROGRESSION IN TRADESCANTIA
Authors: HUSH JULIA , WU LIPING , JOHN PETER C. L. , HEPLER LUKAS H. , HEPLER PETER K.
Published: October 2002

The regulation of mitosis in higher plant cells has been investigated by microinjecting protein kinase from the metaphase‐arresting (met1) mutant ofChlamydomonas. Biochemical characterization of this enzyme complex confirms the presence of a p34cdc2/cyclin B‐like kinase. The enzyme was injected into living stamen hair cells ofTradescantia virginianain which microtubules (MTs) were visualized using fluorescent analogue cytochemistry and confocal laser scanning microscopy. Microinjection of this p34cdc2/cyclin B‐like kinase caused rapid disassembly of the preprophase band of MTs but not of interphase‐cortical, spindle or phragmoplast MTs. Effects of the enzyme on the cytomorphology of live prophase cells were also monitored using video microscopy. We found that injection of this enzyme accelerated chromatin condensation and nuclear envelope breakdown. This indicates the presence and function in plants of an enzyme that can initiate nuclear division similar to the maturation or mitosis promoting factor (MPF) of animal cells. These studies provide the first direct evidence that the mitotically‐active form of plant MPF can drive disassembly of preprophase band MTs, chromosome condensation and initiation of mitosis in plant cells.
TRANSPORT OF GLUTATHIONE S‐CONJUGATES IN THE YEASTSSACCHAROMYCES CEREVISIAE
Authors: ŻĄDZIŃSKI ROLAND , MASZEWSKI JANUSZ , BARTOSZ GRZEGORZ
Published: October 2002

Transport of 2,4‐dinitrophenyl‐S‐glutathione (DNP‐SG) and a fluorescent glutathione S‐conjugate, bimane‐S‐glutathione (B‐SG) was studied in the baker's yeasts (S. cerevisiae). Both conjugates were exported from the cells; the transport was inhibited by fluoride and vanadate like in mammalian cells. B‐SG was also found to be accumulated in the vacuoles. The transport rate of DNP‐SG outside the cell was higher in a vacuolar‐deficient strain. A significant ATP‐dependent uptake of (3H)‐DNP‐SG by vacuoles was found. These results indicate thatS. cerevisiaetransport glutathione S‐conjugates both outside the cells and into the vacuoles.