bluuebunny/crossref_metadata_2025 huggingface dataset:
Sociospatial Differentiation in Urban China: Evidence from Shanghai's Real Estate Markets
Authors: Wu Fulong
Published: October 2002

Market-oriented economic reform has led to an increase in social stratification in urban China. The reform of state-owned enterprises has meant that millions of workers have been ‘laid-off’, while the emergence of a private sector is creating thousands of ‘new rich’. Little is known about the spatial implications of the reform. The huge contrast between commercially developed housing estates and dilapidated inner-city areas is easily seen. However, there is a lack of systematic understanding of the extent to which urban space is differentiated in postreform China. The main obstacle to this understanding is the lack of small-area demographic data. Moreover, spatial data at a high resolution often remain confidential and hence underutilised. The author uses data from Shanghai's real estate market to examine the spatial differentiation of housing prices, so as to shed light on the transformation of urban space. The pattern identified by the analysis of price distribution and the contribution of the environment to property price is remarkably similar to the mental images of ‘upper end’ and ‘lower end’ that are commonly used in Shanghai dialect. Based on this research, three implications are suggested. First, the foremost impact of housing commodification is the revitalisation of the presocialist spatial division, because the socialist transformation of the built environment is never complete. Second, further sociospatial differentiation brought about by commercial development will be built upon the continuation of urban fabric. Third, privatisation of real estate itself becomes a source of sociospatial differentiation, because through the real estate market households are able to capitalise properties that were not distributed equally during the socialist period.
Crisis, Recovery, Innovation: Responsive Organization after September 11
Authors: Kelly John , Stark David
Published: October 2002

After the attack on the World Trade Center on September 11, many firms, directly affected by the attack, resumed trading when markets reopened less than a week later. How were these companies able to respond, working under conditions of fear and grief, so quickly and effectively? Drawing on conversations with executives and employees in financial service firms with offices in the World Trade Center and adjacent buildings, this report documents the importance of strong personal ties, lateral self-organization, and nonhierarchical relations in the recovery process. As a response to uncertainty, organizational factors that explain recovery are similar to those that generate innovation.
Visualizing Decisionmaking: Perspectives on Collaborative and Participative Approach to Sustainable Urban Planning and Management
Authors: Alshuwaikhat Habib M , Nkwenti Danjuma I
Published: October 2002

Over the last two decades shifting human resources, socioeconomic potentials, and innovations in information technology and communication have all but overthrown the formal order of the planning and management of urban systems. The authors trace the causes to misplaced priorities in urban governance and related issues, via the interface of infrastructure systems and land use. They survey some major theoretical and applied decision-support systems collaborative planning systems, and collaborative decision-support systems which have been advanced to date, indicating their strengths and weaknesses with regard to their ability to anchor public participation and professional collaboration in key planning and management issues. They highlight the fact that, although relevant multivariate, disaggregated, and incoherent small-scale researches do yield high dividends, their lack of cohesive interrelationship is related to the fragmentation of urban systems—despite various attempts at bringing about sustainable development. They suggest that decisionmaking can be effective when all aspects involved are visually related and collectively executed. They conclude by emphasizing that a comprehensive approach needs to be adopted for the planning and management of urban centers in order to enhance systems performance, human interaction, and contained developments.
Backbone Topology, Access, and the Commercial Internet, 1997–2000
Authors: O'Kelly Morton E , Grubesic Tony H
Published: October 2002

As the Internet grows in popularity, telecommunications infrastructure in the United States continues to increase in capacity and geographic reach to meet market demand. Important components of this infrastructure include the commercial fiber-optic backbones used to transport digital information between locations. The spatial organization of commercial Internet backbones reflects an increasingly competitive privatized market for service provision, in which certain locations are more accessible and better connected than others. The authors have three objectives. First, they explore the current state of the telecommunications industry, paying special attention to current trends, mergers, and new company business models. Second, they use a standardized methodology to examine the topological structure of the US commercial Internet and the resulting differences in city accessibility. Third, this methodology is put to the test by an exploration of an empirical database of 41 network providers in the United States. Results suggest that significant changes in city accessibility to the commercial Internet occurred between 1997 and 2000.
Reinvention of Tradition as an Urban Image: The Case of Ankara Citadel
Authors: Erendil Asuman Türkün , Ulusoy Zuhal
Published: October 2002

Debates on urban tourism have been coupled with a widespread discourse on ‘placelessness’, ‘loss of identity’, and ‘standardization’ related to the modernist ideology of planning. In this respect, utilizing this historic urban fabric has become important as a means of recreating an urban image. Ironically, efforts to avoid standardization are caught in another trap of sameness and blandness, because a very similar vocabulary is used in the ability of those tourist-historic places to meet the expectations of the universal tourist industry. In this context, we analyzed the recent efforts to integrate an inner-city area, Ankara Citadel and its vicinity, focusing on the changing identity owing to the introduction of income-generating and tourist-attraction facilities. The nature and consequences of this transformation have been investigated in terms of the issues of preservation practice, economic feasibility, public interest, and its ethics and legitimacy.
Modeling the Formation of Activity Agendas Using Reactive Agents
Authors: Arentze Theo , Timmermans Harry
Published: October 2002

The scheduling of daily activities requires decisions to be made on which activities to conduct, where, when, for how long, and the transport mode involved. In a common conceptualization of the decision process, a multitude of time frames is involved. Longer term decisions determine the allocation of time across main activity categories as well as the profiling of institutionalized activities such as work and some leisure activities. The authors introduce a conceptual framework for modeling the formation of activity agendas that represents the results of such longer term decisions. The framework identifies the elementary decisions and arranges these decisions in a hierarchy. In the proposed system, the decisions are handled by a set of relatively autonomous interacting agents.
Encoding Natural Movement as an Agent-Based System: An Investigation into Human Pedestrian Behaviour in the Built Environment
Authors: Turner Alasdair , Penn Alan
Published: October 2002

Gibson's ecological theory of perception has received considerable attention within psychology literature, as well as in computer vision and robotics. However, few have applied Gibson's approach to agent-based models of human movement, because the ecological theory requires that individuals have a vision-based mental model of the world, and for large numbers of agents this becomes extremely expensive computationally. Thus, within current pedestrian models, path evaluation is based on calibration from observed data or on sophisticated but deterministic route-choice mechanisms; there is little open-ended behavioural modelling of human-movement patterns. One solution which allows individuals rapid concurrent access to the visual information within an environment is an ‘exosomatic visual architecture’, where the connections between mutually visible locations within a configuration are prestored in a lookup table. Here we demonstrate that, with the aid of an exosomatic visual architecture, it is possible to develop behavioural models in which movement rules originating from Gibson's principle of affordance are utilised. We apply large numbers of agents programmed with these rules to a built-environment example and show that, by varying parameters such as destination selection, field of view, and steps taken between decision points, it is possible to generate aggregate movement levels very similar to those found in an actual building context.
Determinants of Environmental Clean-up in Estonia
Authors: Auer Matthew R , Raukas Anto
Published: October 2002

In the early 1990s, the government of Estonia determined that it possessed neither the technical nor the financial resources to clean up Estonia's Soviet-era pollution satisfactorily. Yet data reveal that, during the 1990s, Estonia was relatively adept at cleaning up old contamination. In this paper we identify the key determinants of Estonia's relatively high level of success at environmental remediation. Content analyses of clean-up experiences were performed for three main categories of contaminated sites: ex-military, industrial, and municipal. All analyzed sites were identified by the government of Estonia as priority environmental hot spots in the early 1990s. The most successfully remediated sites were recipients of foreign direct investment or foreign aid, or both, and particularly aid from international financial institutions (IFIs). IFIs and foreign private actors were persuaded to act because of their confidence in the income-generating potential of the projects. In light of this finding, revisions must be made to an oft-cited model of ‘institutions for international environmental cooperation’. In its current form, this model downplays external actors' market-oriented motives.
Global and Local Contributions to the Optical Specification of Time to Contact: Observer Sensitivity to Composite Tau
Authors: Bootsma Reinoud J , Craig Cathy M
Published: October 2002

First-order time remaining until a moving observer will pass an environmental element is optically specified in two different ways. The specification provided by global tau (based on the pattern of change of angular bearing) requires that the element is stationary and that the direction of motion is accurately detected, whereas the specification provided by composite tau (based on the patterns of change of optical size and optical distance) does not require either of these. We obtained converging evidence for our hypothesis that observers are sensitive to composite tau in four experiments involving relative judgments of time to passage with forced-choice methodology. Discrimination performance was enhanced in the presence of a local expansion component, while being unaffected when the detection of the direction of heading was impaired. Observers relied on the information carried in composite tau rather than on the information carried in its constituent components. Finally, performance was similar under conditions of observer motion and conditions of object motion. Because composite tau specifies first-order time remaining for a large number of situations, the different ways in which it may be detected are discussed.
Amodal Completion and the Perception of Depth without Binocular Correspondence
Authors: Bacon Benoit A , Mamassian Pascal
Published: October 2002

Half-occlusions and illusory contours have recently been used to show that depth can be perceived in the absence of binocular correspondence and that there is more to stereopsis than solving the correspondence problem. In the present study we show a new way for depth to be assigned in the absence of binocular correspondence, namely amodal completion. Although an occluder removed all possibility of direct binocular matching, subjects consistently assigned the correct depth (convexity or concavity) to partially occluded ‘folded cards’ stimuli. Our results highlight the importance of more global, surface-based processes in stereopsis.
Effects of Visual-Field Inversions on the Reverse-Perspective Illusion
Authors: Cook Norman D , Hayashi Takefumi , Amemiya Toshihiko , Suzuki Kimihiro , Leumann Lorenz
Published: October 2002

The ‘reverse-perspective’ illusion entails the apparent motion of a stationary scene painted in relief and containing misleading depth cues. We have found that, using prism goggles to induce horizontal or vertical visual-field reversals, the illusory motion is greatly reduced or eliminated in the direction for which the goggles reverse the visual field. We argue that the illusion is a consequence of the observer's inability to reconcile changes in visual information due to body movement with implicit knowledge concerning anticipated changes. As such, the reverse-perspective illusion may prove to be useful in the study of the integration of linear perspective and motion parallax information.
Attention to Faces: A Change-Blindness Study
Authors: Davies Temre N , Hoffman Donald D
Published: October 2002

What strategies does human vision use to attend to faces and their features? How are such strategies altered by 2-D inversion or photographic negation? We report two experiments in which these questions were studied with the flicker task of the change-blindness literature. In experiment 1 we studied detection of configural changes to the eyes or mouth, and found that upright faces receive more efficient attention than inverted faces, and that faces shown with normal contrast receive more efficient attention than faces shown in photographic negative. Moreover, eyes receive greater attention than the mouth. In experiment 2 we studied detection of local changes to the eyes or mouth, and found the same results. It is well known that inversion and negation impair the perception and recognition of faces. The experiments presented here extend previous findings by showing that inversion and negation also impair attention to faces.
The LIM-only protein FHL2 interacts with β-catenin and promotes differentiation of mouse myoblasts
Authors: Martin Bernd , Schneider Richard , Janetzky Stefanie , Waibler Zoe , Pandur Petra , Kühl Michael , Behrens Jürgen , von der Mark Klaus , Starzinski-Powitz Anna , Wixler Viktor
Published: October 2002

FHL2 is a LIM-domain protein expressed in myoblasts but down-regulated in malignant rhabdomyosarcoma cells, suggesting an important role of FHL2 in muscle development. To investigate the importance of FHL2 during myoblast differentiation, we performed a yeast two-hybrid screen using a cDNA library derived from myoblasts induced for differentiation. We identified β-catenin as a novel interaction partner of FHL2 and confirmed the specificity of association by direct in vitro binding tests and coimmunoprecipitation assays from cell lysates. Deletion analysis of both proteins revealed that the NH2-terminal part of β-catenin is sufficient for binding in yeast, but addition of the first armadillo repeat is necessary for binding FHL2 in mammalian cells, whereas the presence of all four LIM domains of FHL2 is needed for the interaction. Expression of FHL2 counteracts β-catenin–mediated activation of a TCF/LEF-dependent reporter gene in a dose-dependent and muscle cell–specific manner. After injection into Xenopus embryos, FHL2 inhibited the β-catenin–induced axis duplication. C2C12 mouse myoblasts stably expressing FHL2 show increased myogenic differentiation reflected by accelerated myotube formation and expression of muscle-specific proteins. These data imply that FHL2 is a muscle-specific repressor of LEF/TCF target genes and promotes myogenic differentiation by interacting with β-catenin.
High‐throughput clonal selection of recombinant CHO cells using a dominant selectable and amplifiable metallothionein‐GFP fusion protein
Authors: Bailey Charles G. , Tait A. Sasha , Sunstrom Noelle‐Ann
Published: October 2002

Transfected mammalian cells can be used for the production of fully processed recombinant proteins for medical and industrial purposes. However, the isolation of high‐producing clones is traditionally time‐consuming. Therefore, we developed a high‐throughput screening method to reduce the time and effort required to isolate high‐producing cells. This involved the construction of an expression vector containing the amplifiable gene metallothionein (MT), fused in‐frame to green fluorescent protein (GFP). The fusion gene (MTGFP) confers metal resistance similar to that of the wild‐type metallothionein and expression can be monitored using either flow cytometry or a fluorometer to measure green fluorescence. Expression of MTGFP acted as a dominant selectable marker allowing rapid and more efficient selection of clones at defined metal concentrations than with the antibiotic G418. Cells harboring MTGFP responded to increasing metal concentrations with a corresponding increase in fluorescence. There was also a corresponding increase in recombinant protein production, indicating that MTGFP could be used as a selectable and amplifiable gene for the coexpression of foreign genes. Using our expression vector encoding MTGFP, we demonstrate a high‐throughput clonal selection protocol for the rapid isolation of high‐producing clones from transfected CHO cells. We were able to isolate cell lines reaching specific productivities of >10 μg hGH/106 cells/day within 4 weeks of transfection. The advantage of this method is that it can be easily adapted for automated procedures using robotic handling systems. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 670–676, 2002.
Impact of coexpression and coamplification of sICAM and antiapoptosis determinants bcl‐2/bcl‐xL on productivity, cell survival, and mitochondria number in CHO‐DG44 grown in suspension and serum‐free media
Authors: Meents Heiko , Enenkel Barbara , Eppenberger Hans M. , Werner Rolf G. , Fussenegger Martin
Published: October 2002

We have engineered dihydrofolate reductase‐negative (dhfr−/−) Chinese hamster ovary (CHO) DG44 cells adapted for growth in serum‐free suspension cultures for simultaneous expression of the common cold therapeutic, the soluble intercellular adhesion molecule 1 (sICAM), and the antiapoptosis determinants bcl‐2 or bcl‐xL. Detailed analyses of titer and antiapoptosis characteristics of these production cell lines included an independent (sICAM; bcl‐2/bcl‐xL) as well as a cocistronic (sICAM‐(bcl‐2/bcl‐xL)) expression set‐up in which translation–initiation of the survival cistron is driven by an internal ribosome entry site (IRES) of the encephalomyocarditis virus (EMCV). In transient transfections or stable mixed populations and in comparison to isogenic sICAM‐only control vectors, both bcl‐xL‐encoding configurations achieved higher sICAM yields while bcl‐2 over‐expression resulted in decreased product levels. Overall, the death‐protective impact of bcl‐2 and bcl‐xL in engineered CHO‐DG44 was not significant under typical batch‐mode operation, an observation that was confirmed by clonal analysis. bcl‐2 and bcl‐xL displayed their antiapoptosis potential only following dhfr‐based amplification in sICAM‐producing CHO‐DG44 cell lines. In all cases, bcl‐xL outperformed bcl‐2 in its cell death‐protective capacity. Amplification‐dependent high‐level expression of mitochondria‐localized bcl‐2 family members required for successful antiapoptosis engineering may be essential to compensate for increased mitochondria numbers found to be associated with production cell lines grown in serum‐free medium. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 706–716, 2002.
Supercritical fluid extraction for the separation of organochlorine pesticides residue in Angelica sinensis
Authors: Zhao Chunjie , Hao Guiming , Li Huanxin , Chen Yingjie
Published: October 2002

A method involving the simultaneous extraction and separation of 12 organochlorine pesticides (OCPs) from Angelicae sinensis was developed using supercritical fluid extraction (SFE). The pesticides in the study were α‐, β‐, γ‐ and δ‐benzene hexachloride, PCNB (pentachloro‐ nitrobenzene), PCA (pentachloroaniline), HEPT (heptachlor), MPCPS (methyl‐pentachlorophenyl sulfide), pp′‐DDE [1,1‐dichloro‐2,2‐bis (p‐chlorophenyl) ethylene], op′‐DDT [1,1,1,‐trichloro‐2‐(o‐chlorophenyl)‐2‐(p‐chlorophenyl) ethane], pp′‐DDD [1,1‐dichloro‐2,2‐bis(p‐chlorophenyl) ethane], and pp′‐DDT [1,1,1,‐trichloro‐2,2‐bis (p‐chlorophenyl)ethane]. The extraction conditions were optimized as follows: pure CO2, extraction pressure 15 MPa, extraction temperature 60°C, extraction time 20 min, and flow‐rate 1.5 mL/min. A GC method with electron capture detection was employed to determine the OCPs in Angelicae sinensis. An HPLC method was developed for the quantitative determination of active constituents. The SFE provided high decontamination rate of OCPs and low loss of active constituents in Angelicae sinensis. Copyright © 2002 John Wiley & Sons, Ltd.
A modified HPLC method for the determination of ochratoxin A by fluorescence detection
Authors: Aboul‐Enein Hassan Y. , Kutluk Özlem Banu , Altiokka Göksel , Tunçel Muzaffer
Published: October 2002

A high‐performance liquid chromatographic method (HPLC) with fluorescent detector is described for the determination of ochratoxin A (OTA). A mobile phase consisting of acetonitrile:water:acetic acid (99:99:2, v/v/v) was used for the resolution of the compound on a C18 Hypersil column. The retention time for OTA and diflunisal which was used as an internal standard (IS) were 11.7 and 12.8 min, respectively. The method is selective, reliable, reproducable with relative standard deviation (RSD) of 1.70 and linear in the range of 2.5 × 10−9–1.5 × 10−8 M OTA. The limit of detection (LOD) and limit of quantification (LOQ) were 2.5 × 10−10 M corresponding to 0.1 ng mL−1 and 8.2 × 10−10 corresponding to 3.3 ng mL−1, respectively. Recovery studies were 81.2 ± 1.9 (SD). The method was applied for analysis of OTA in wheat, corn, red pepper, cheese and wine. The proposed method can be used for the routine analysis of OTA in food and animal feed. Copyright © 2002 John Wiley & Sons, Ltd.
Dynamic group multicast routing with bandwidth reservations
Authors: Low Chor Ping , Wang Ning , Ng Jim Mee
Published: October 2002

Multicasting refers to the transmission of data from a source node to multiple destination nodes in a network. Group multicasting is a generalization of multicasting whereby every member of a group is allowed to multicast messages to other members that belong to the same group. The routing problem in this case involves the construction of a set of low cost multicast trees with bandwidth requirements, one for each member of the group for multicasting messages to other members of the group. In this paper, we examine this routing problem with an additional requirement that member nodes are allowed to join and leave the multicasting group anytime during a session. We call this problem, the dynamic group multicast routing problem (DGMRP). In this paper, we proposed three heuristic algorithms to generate a set of low cost multicast trees with dynamic group membership. Results from our empirical study shows that the one of the proposed algorithms, called Maximum bandwidth bottleneck path selection algorithm (MBBPS), achieves better utilization of bandwidth resources as compared with the other two algorithms which are based on a greedy approach. In addition MBBPS performs better in terms of cost when the bandwidth is not sufficient in the network. Copyright © 2002 John Wiley & Sons, Ltd.
The policy relevance of environmental protection expenditure accounting
Authors: Barry Conor P. , Convery Frank J.
Published: October 2002

As a result of theoretical concerns about the use of GDP as the main policy indicator, and the implications this may have for the achievement of other policy goals, the UN proposed a system of integrated environmental and economic accounting (SEEA). Part of their guidelines recommends the collection of data regarding environmental protection expenditure (EPE). Both EUROSTAT and the OECD have designed and implemented methodologies with the aim of producing EPE accounts for international comparison. While much effort has been employed in examining and refining the design and implementation, to date little has been said regarding the policy relevance of such accounts. We have applied the Eurostat and OECD methodologies to produce the first ever EPE dataset for Ireland. This work involved a detailed examination of both public and private sector environmental expenditure and estimated that EPE in Ireland was equal to just under 1% of GDP in 1998. We conclude that the main policy relevance lies in the assessment of the potential for industries involved in the supply and operation of environmental abatement services in Ireland. To the extent that expenditure can be disaggregated to sectoral level in those sectors exposed to international competition, it can also inform a discussion about the relation between environmental compliance costs and sectoral competitiveness. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment.
A fast Godunov method for the water‐hammer problem
Authors: Hwang Yao‐Hsin , Chung Nien‐Mien
Published: October 2002

An efficient Godunov‐type numerical method with second‐order accuracy was developed to simulate the water‐hammer problem in piping. The exact solutions of the Riemann problem were analysed and illustrated on the intriguing solution diagram by properly introducing dimensionless variables within reasonably practical ranges. Based on the solution diagram, an efficient fast Riemann solver was also developed. Moreover, small perturbation analysis was performed to demonstrate the relations between the primitive variables, velocity and pressure, for the Riemann problem. The typical shock‐tube problem and the water‐hammer problem were implemented as sample ones to test the numerical method. It was shown that the present numerical method incorporated with Van Leer's flux limiter is a promising one to simulate fluid transient problem for piping in the present study. Copyright © 2002 John Wiley & Sons, Ltd.
Separation of aqueous isopropanol by reactive extractive distillation
Authors: Zhigang Lei , Jinchang Zhang , Biaohua Chen
Published: October 2002

A new separation method of reactive extractive distillation is proposed for the separation of isopropanol and water, using the mixture of ethylene glycol (C2H6O2) and glycollic potassium (C2H5O2K) as an entrainer. Vapor–liquid‐equilibrium (VLE) measurements confirmed that the entrainer was effective for this separation. Using a feed/solvent volume ratio of 1:1, isopropanol with a concentration over 96.0% weight fraction was obtained by the reactive extractive distillation process and the azeotropic point was eliminated. A novel process of separating isopropanol and water is designed on the basis of reactive extractive distillation to obtain the product with different concentrations, which may have a lasting value in industry.

© 2002 Society of Chemical Industry
Strain‐driven homogenization of inelastic microstructures and composites based on an incremental variational formulation
Authors: Miehe Christian
Published: October 2002

The paper investigates computational procedures for the treatment of a homogenized macro‐continuum with locally attached micro‐structures of inelastic constituents undergoing small strains. The point of departure is a general internal variable formulation that determines the inelastic response of the constituents of a typical micro‐structure as a generalized standard medium in terms of an energy storage and a dissipation function. Consistent with this type of inelasticity we develop a new incremental variational formulation of the local constitutive response where a quasi‐hyperelastic micro‐stress potential is obtained from a local minimization problem with respect to the internal variables. It is shown that this local minimization problem determines the internal state of the material for finite increments of time. We specify the local variational formulation for a setting of smooth single‐surface inelasticity and discuss its numerical solution based on a time discretization of the internal variables. The existence of the quasi‐hyperelastic stress potential allows the extension of homogenization approaches of elasticity to the incremental setting of inelasticity. Focusing on macro‐strain‐driven micro‐structures, we develop a new incremental variational formulation of the global homogenization problem where a quasi‐hyperelastic macro‐stress potential is obtained from a global minimization problem with respect to the fine‐scale displacement fluctuation field. It is shown that this global minimization problem determines the state of the micro‐structure for finite increments of time. We consider three different settings of the global variational problem for prescribed linear displacements, periodic fluctuations and constant stresses on the boundary of the micro‐structure and discuss their numerical solutions based on a spatial discretization of the fine‐scale displacement fluctuation field. The performance of the proposed methods is demonstrated for the model problem of von Mises‐type elasto‐visco‐plasticity of the constituents and applied to a comparative study of micro‐to‐macro transitions of inelastic composites. Copyright © 2002 John Wiley & Sons, Ltd.
Reference values of fetal orbital measurements by transvaginal scan in early pregnancy
Authors: Rosati Paolo , Bartolozzi Francesco , Guariglia Lorenzo
Published: October 2002

Objective

To construct reference ranges of orbital diameters, measured in early pregnancy by transvaginal sonography.

Methods

The study group consisted of 2717 fetuses of pregnant women referred to our center and examined by transvaginal ultrasound between 11–16 week's gestation. Nomograms with confidence intervals (5th and 95th percentile) for each orbital measurement (orbital diameter, interocular and binocular distance) versus gestational age were produced.

Results

The orbital measurements increased in a linear fashion throughout early pregnancy with a good correlation with gestational age.

Conclusion

Transvaginal sonography is able to visualize and measure orbital diameters with accuracy in early pregnancy; reference ranges were developed that can be used to evaluate normal orbital development and can be helpful in the detection of syndromes with orbital growth defects and other associated fetal anomalies. Copyright © 2002 John Wiley & Sons, Ltd.
Advances in fibre‐reinforced polymer composite bridge decks
Authors: Hota GangaRao V S , Hota Siva R V
Published: October 2002

Utilization of thermoset or thermoplastic resins binding glass and/or carbon fabrics has led to advanced fibre‐reinforced polymer (FRP) composite materials, structural shapes, and systems. Innovative FRP composite bridge deck production processes have been developed and perfected. Two of these processes are pultrusion and resin transfer moulding. A number of structural systems implemented as bridge decks are described. Construction and design details of composite decks are also provided.
Barrett’s Esophagus Complicated with Stricture: Correlation between Classification and the Results of the Different Therapeutic Options
Authors: Braghetto Italo , Csendes Attila , Burdiles Patricio , Korn Owen , Compan Alvaro , Guerra Juan F.
Published: October 2002

Benign esophageal stricture is a serious complication of persistent gastroesophageal reflux in patients with esophagitis and Barrett’s esophagus. A classification of the severity of the stricture is proposed, based on its internal diameter, its length, and the ease or difficulty in dilating it. Among 185 patients with esophageal strictures secondary to reflux esophagitis, 77 (41.6%) corresponded to type I or mild stricture, 73 (39.4%) to type II or moderate, and 35 (19.6%) to type III. Medical treatment was performed in only 15 cases, with 73% recurrence. Three types of surgical procedures were employed, always after dilatation, improvement of nutritional status, and a complete preoperative work‐up: (1) conservative antireflux surgery, which had a high incidence of recurrence (41.1%); (2) acid suppression and duodenal diversion, in which 68 patients had a mortality rate of 2.9% and a recurrence rate of 4.4% (p <0.002); and (3) esophageal resection, which in 7 patients resulted in 1 death and no late recurrence. It is concluded that classification of the severity of the stricture is important to indicate the most appropriate treatment. Conservative antireflux surgery is followed by a high recurrence rate at late follow‐up, whereas acid suppression and duodenal diversion seem to be an adequate procedure that is followed by a very low recurrence rate. Esophageal resection is indicated only for patients with severe or critical esophageal strictures.
History of the ISS/SIC: Antoine Depage, One of the Founders of the ISS/SIC
Authors: Van Hee R.
Published: October 2002

Antoine Depage, born near Brussels in
1862, was one of the founders and first Secretary General of the Société Internationale de Chirurgie (ISS–SIC). After an excellent medical education at the Free Brussels University, he became professor at the same university at the age of 27. Surgically trained by Prof. Thiriar, he became one of the leading Belgian surgeons at the end of the nineteenth century, and he published more than 100 articles in national and international journals. In 1907 he founded a school for nurses in Brussels, to be directed by Edith Cavell. He also vigorously transformed the organization of the public hospitals in the Belgian capital. During World War I Queen Elisabeth appointed him surgeon‐in‐chief of the Océan‐hospital in De Panne, where more than 50,000 soldiers with wounds, fractures, cerebral trauma, nitrous gas intoxication, and infectious diseases, among other problems were treated. The results he and his team obtained were excellent, and mortality was low. Many surgeons, including Alexis Carrel, as well as distinguished political leaders came to visit him in the hospital barracks. After the war he was honored by many political and scientific organizations, including the Société Internationale de Chirurgie. He served our Society not only as Secretary General from
1902 to 1912 but became President of the 4th Congress of the ISS–SIC in New York. Antoine Depage died after a long illness in 1925.
Collis‐Nissen Procedure in Patients with Esophageal Atresia: Long‐term Evaluation
Authors: Kawahara Hisayoshi , Imura Kenji , Yagi Makoto , Kubota Akio , Okada Akira
Published: October 2002

A subset of patients with esophageal atresia (EA) have an associated short esophagus and require an antireflux procedure. The Collis‐Nissen procedure, which consists of a combination of Collis gastroplasty and Nissen fundoplication, is considered an option in such conditions. The long‐term results of EA patients undergoing this procedure have rarely been reported. The results of the Collis‐Nissen procedure were examined in four EA patients with follow‐up for an average of 9 years. The Collis‐Nissen procedure was conducted concurrently with segmental esophageal resection for an associated congenital esophageal stenosis close to the esophagogastric junction in two postoperative Gross type C patients (7
months, 2 years), as an antireflux operation in a postoperative Gross type A patient with an unreducible sliding hiatal hernia (10 years),
and with primary repair of EA in a Gross type A patient with a long gap
(4 months). There were no significant complications except minor anastomotic leakage and an anastomotic stenosis that required postoperative dilation. Significant reflux was negative, as shown by an upper gastrointestinal study and scintigraphy. Limited esophagitis just above the esophagogastric junction was observed in a Gross type A patient with a long mediastinal gastric segment. Swallow‐related pressure reduction at the wrapping cuff was detected by manometric examination. The Collis‐Nissen procedure is a useful option for treating EA patients who require esophageal lengthening and control of gastroesophageal reflux.
Early Experience with the Nuss Minimally Invasive Correction of Pectus Excavatum in Adults
Authors: Coln Dale , Gunning Tom , Ramsay Michael , Swygert Tom , Vera Richard
Published: October 2002

Nuss described a minimally invasive technique for correcting pectus excavatum in children. A curved stainless‐steel bar is inserted behind the sternum through the chest cavity with the convex surface face down, then rotated 180 degrees to elevate the sternum and correct the deformity. The procedure gained wide acceptance in children. The purpose of this study was to determine if the procedure is effective in adults. Only patients with symptoms limiting lifestyle, chest wall indices higher than 3.25, and demonstrable cardiac compression on echocardiography were accepted.
Between April 1998 and January 2001, 14 adults aged 19 to 46 underwent assessment for the Nuss minimally invasive technique for correction of pectus excavatum. Eight patients, 19 to 32 years of age, met the stated criteria for acceptance. The comorbidities were 2 asymmetrical deformities, 2 scolioses, 1 previous pectus repair, and 1 previous breast augmentation. The patients were informed of the benefits and disadvantages of both the Ravitch and the Nuss procedures. All patients except the first had talked to one or more adults who previously had the procedure. Follow‐up was 7 to 37 months (mean 22.1 months). Four patients have had their bars removed and maintained correction. Success of the operation was based on relief of cardiac compression,
alleviation of symptoms, and adequate pain control. Operating time was
1 to 2:05 hours (mean 1:32 hours). Complications were pneumothorax in one patient, urinary retention in 2, and left lower lobe atelectasis in
5. Complications did not prolong hospitalization. Postoperative epidural analgesia was discontinued after 2 to 4 days (mean 2.8 days).
Average daily pain scores were between 1.6 and 3.7 on a scale of 0 to
10. Hospital stay was 3 to 5 days (mean 4 days). Relief of symptoms and increase in activity were obtained in all patients. Relief of cardiac compression was demonstrated in the 6 patients who have had postoperative echocardiograms. Patients returned to normal activity 2
to 4 weeks postoperatively (mean 2.3 weeks). Duration of pain medicine was 2 to 4 weeks in 6 patients and 2 and 4 months for the other 2 (mean
5.5 weeks). There were 2 late complications related to the bar, but without loss of correction. The early experience with the Nuss minimally invasive pectus excavatum repair in adults is encouraging.
The procedure is effective for correcting pectus excavatum in selected patients. Early results are dependent upon adequate bar stabilization and pain control. The long‐term results in adults are unknown.
Transplantation of Adrenal Tissue Fragments in a Murine Model: Functional Capacities of Syngeneic and Allogeneic Grafts
Authors: Musholt Thomas J. , Klebs Sven H. G. , Musholt Petra B. , Ellerkamp V. , Klempnauer Juergen , Hoffmann Matthias W.
Published: October 2002

Oral hormone substitution for the treatment of Addison’s disease inadequately replaces the physiologic circadian secretion of corticosteroids. Alternative therapeutic approaches are reimplantation of healthy autologous adrenal tissue and allogeneic transplantation (Tx), respectively. The aim of our study was to evaluate the functional capacity of adrenal grafts and the influence of intercellular adhesion molecule‐1 (ICAM‐1) on graft survival.
Fragmented adrenal glands of wild‐type B10.BR (H‐2k) and wild‐type or ICAM‐1‐deficient BALB/c (H‐2d) mice were transplanted underneath the kidney capsule of adrenalectomized B10.BR mice [complete major histocompatibility complex (MHC) haplotype disparity in the latter]. Postoperatively, the endocrine function of the adrenal grafts was evaluated by the following parameters: (1)
survival analysis of the recipients (termination at day 70 after Tx);
(2) reverse transcription‐polymerase chain reaction expression analysis of aldosterone synthase (zona glomerulosa‐specific) and of
11b‐hydroxylase (zona fasciculata‐specific); and (3) measurement of basal adrenocorticotropic hormone (ACTH) stimulated serum corticosterone levels. Expression of both enzyme‐specific mRNAs was detected in the grafts at any time during the post‐Tx period. The adrenal grafts of syngeneic and surviving MHC‐disparate mice displayed a similar basal hormone secretion, which was about 60% lower than that in sham‐operated animals. In the transplanted mice, ACTH‐stimulated corticosterone measurement revealed a 5‐ to 10‐fold decreased functional reserve capacity. ICAM‐1 deficiency significantly prolonged the survival of adrenal grafts. Fragmented adrenal grafts are able to maintain physiologic basal corticosterone levels but had markedly reduced reserve capacity. Nevertheless, the results give rise to hopes that autologous or MHC‐compatible allogeneic transplantation of adrenal grafts may replace oral hormone substitution in humans.
Endoscopic Treatment of Solitary, Bilateral, Multiple, and Recurrent Pheochromocytomas and Paragangliomas
Authors: Walz Martin K. , Peitgen Klaus , Neumann Hartmut P.H. , Janssen Onno E. , Philipp Thomas , Mann Klaus
Published: October 2002

Because of extensive intraoperative catecholamine release, extreme vascularization, and demanding localization, laparoscopic and retroperitoneoscopic excision of pheochromocytomas and retroperitoneal paragangliomas is challenging. In a prospective clinical study, 61 chromaffin neoplasms (52 pheochromocytomas, 9 paragangliomas) were removed endoscopically from 52 patients (30 males, 22 females; age 44.4 ± 16.3 years) at 55
operations. Six patients showed multiple (two to five) tumors. Tumor size ranged from 1 to 7 cm (mean 3.6 ± 1.4 cm). Twelve patients suffered from hereditary diseases. Seven patients had bilateral adrenal diseases; in three patients pheochromocytomas were removed on both sides synchronously. Four neoplasias were local recurrences (three pheochromocytomas, one paraganglioma).
The laparoscopic route was chosen for six operations, and the retroperitoneoscopic technique was performed in 49 procedures. Partial adrenalectomy was performed in 19 operations (in all patients with bilateral diseases). High‐dosage a‐blockage with phenoxybenzamine was routinely used. There were no conversions to open surgery. Perioperative complications were minor (23%), and mortality was zero. The operating time for unilateral pheochromocytomas was 116 ± 52 minutes (range 35–285
minutes) and depended on tumor size (<3 cm vs. ≥ 3 cm;
p <0.01), gender (p <0.01), and extent of resection (partial vs.
complete; p <0.05). The operating time for bilateral pheochromocytomas ranged from 285 to 385 minutes, and it was 75 to
600 minutes for paragangliomas. Blood loss was 100 ± 171 ml. Consumption of analgesics was low (mean 7 mg piritramide postoperatively). The median duration of postoperative hospitalization was 4 days. In six of seven patients with bilateral disease complete preservation of cortical function was achieved.
Locoregional metastatic recurrence was found in one patient 3 years after retroperitoneoscopic adrenalectomy. Endoscopic removal of solitary, bilateral,
multiple, and recurrent pheochromocytomas and retroperitoneal paragangliomas is feasible and safe but requires extensive experience in minimally invasive and endocrine surgery.
Radiofrequency Tissue Ablation Using Cooled Tip for Liver Metastases of Endocrine Tumors
Authors: Hellman Per , Ladjevardi Sam , Skogseid Britt , Åkerström Göran , Elvin Anders
Published: October 2002

Tumors derived from hormone‐producing cells are generally highly differentiated, and vast experience indicates benefit with combinations of surgical and medical treatment for metastatic disease. Tumor debulking surgery is an accepted approach for reducing hormonal symptoms and to establish better conditions for medical treatment. Radiofrequency treatment (RF), a novel method for destroying liver tumors, was used to treat 43 liver metastases in 21
patients with endocrine tumors (12 with midgut carcinoid disease; 4
with nonfunctional endocrine pancreatic tumors; 1 with a VIPoma; 1 with a glucagonoma; 1 with a gastrinoma; 2 with adrenal carcinomas). Among these patients we treated with intention to cure in 14 by RF alone or RF plus surgery. Ablation was performed either percutaneously or intraoperatively using a cooled‐tip needle, applying 50 to 90 watts over 10 to 12 minutes under ultrasound guidance. Contrast‐enhanced computed tomography, liver function tests, and tumor markers were followed before and after RF. There were two complications: One patient suffered from conservatively treated bile leakage, and another had pleural effusion and fever for 7 days post‐RF. Two lesions developed signs of incomplete necrosis after 6 months, yielding a local recurrence rate of (4.6%). Of the 15 patients treated with curative intent, we attained cure (i.e., no residual macroscopic tumor) in 4
patients. We conclude that RF using cooled‐tip needles is safe and efficient; it may be performed percutaneously and intraoperatively; and it may expand the indications for liver resection.
Importance of Lymph Node Metastases in Follicular Thyroid Cancer
Authors: Witte Jürgen , Goretzki Peter E. , Dieken Jan , Simon Dietmar , Röher Hans D.
Published: October 2002

There are many concepts of risk and prognostic factor analysis for differentiated thyroid cancer. The prognostic role of lymph node metastases in follicular thyroid cancer (FTC), however, is still controversial. We performed a retrospective trial in 186 patients with FTC (124
women, 62 men; mean follow‐up 5.5 years) questioning whether lymph node metastases and radical thyroid surgery with neck dissection contribute to the prognosis of FTC. Univariate analysis demonstrated that lymph node metastasesp <0.005), tumor size (p <0.005), tumor stage (p <0.005), distant metastases p = 0.0063), and gender (p = 0.003) are significant prognostic factors for recurrence (Kaplan‐Meier). Tumor size (p =
0.004), lymph node metastases p = 0.0478), and distant metastases p = 0.0064) influenced mortality. Age and extent of surgery were not significant for recurrence nor was gender for mortality. Multivariate analysis (Cox regression test)
characterized tumor size (p <0.005) and lymph node metastases p = 0.004) as prognostic factors for recurrence of FTC. No significant difference was detected between patients being treated by thyroidectomy when compared to patients treated by thyroidectomy plus neck dissection in relation to recurrence. Our data demonstrate lymph node metastases to be a significant prognostic factor for recurrence of FTC and the patient’s survival. We advocate thyroidectomy plus central lymph node dissection as the basic surgical strategy. For T3 and T4 tumors, unilateral modified neck dissection is an all but optional procedure. Whether radical surgery with thyroidectomy plus neck dissection has an impact on survival remains questionable.