bluuebunny/crossref_metadata_2025 huggingface dataset:
Conductivity dependence of seismoelectric wave phenomena in fluid‐saturated sediments
Authors: Block Gareth I. , Harris John G.
Published: January 2006

Seismoelectric phenomena in sediments arise from acoustic wave–induced fluid motion in the pore space, which perturbs the electrostatic equilibrium of the electric double layer on the grain surfaces. Experimental techniques and the apparatus built to study the conductivity dependence of the electrokinetic (EK) effect are described, and outcomes for studies in loose glass microspheres and medium‐grain sand are presented. By varying the NaCl concentration in the pore fluid, we measured the conductivity dependence of two kinds of EK behavior: (1) the electric fields generated within the samples by the passage of transmitted acoustic waves and (2) the electromagnetic waves produced at the fluid‐sediment interface by the incident acoustic wave. Both phenomena are caused by relative fluid motion in the sediment pores; this feature is characteristic of poroelastic (Biot) media but is not predicted by either viscoelastic fluid or solid models. A model of plane wave reflection from a fluid‐sediment interface using EK‐Biot theory leads to theoretical predictions that compare well to the experimental data for both loose glass microspheres and medium‐grain sand.
CNS Microvascular Pericytes Exhibit Multipotential Stem Cell Activity
Authors: Dore-Duffy Paula , Katychev Andre , Wang Xueqian , Van Buren Eric
Published: January 2006

It has been suggested that a vascular-like cell has multipotent regenerative and mesenchymal lineage relationships. The identity of this stem/progenitor cell has remained elusive. We report here that adult central nervous system (CNS) capillaries contain a distinct population of microvascular cells, the pericyte that are nestin/NG2 positive and in response to basic fibroblast growth factor (bFGF) differentiate into cells of neural lineage. In their microvascular location, pericytes express nestin and NG2 proteoglycan. In serum containing media primary (0 to 7 day old) CNS pericytes are nestin positive, NG2 positive, alpha smooth muscle actin (αSMA) positive, and do not bind the endothelial cell specific griffonia symplicifolia agglutinin (GSA). In serum containing media, pericytes do not undergo neurogenesis but are induced to express αSMA. In bFGF containing media without serum, CNS pericytes form small clusters and multicellular spheres. Differentiated spheres expressed neuronal and glial cell markers. After disruption and serial dilution, differentiated spheres were capable of self-renewal. When differentiated spheres were disrupted and cultured in the presence of serum, multiple adherent cell populations were identified by dual and triple immunocytochemistry. Cells expressing markers characteristic of pericytes, neurons, and glial cells were generated. Many of the cells exhibited dual expression of differentiation markers. With prolonged culture fully differentiated cells of neural lineage were present. Results indicate that adult CNS microvascular pericytes have neural stem cell capability.
Novel Therapeutic Strategy for Stroke in Rats by Bone Marrow Stromal Cells and ex vivo HGF Gene Transfer with HSV-1 Vector
Authors: Zhao Ming-Zhu , Nonoguchi Naosuke , Ikeda Naokado , Watanabe Takuji , Furutama Daisuke , Miyazawa Daisuke , Funakoshi Hiroshi , Kajimoto Yoshinaga , Nakamura Toshikazu , Dezawa Mari , Shibata Masa-Aki , Otsuki Yoshinori , Coffin Robert S , Liu Wei-Dong , Kuroiwa Toshihiko , Miyatake Shin-Ichi
Published: January 2006

Occlusive cerebrovascular disease leads to brain ischemia that causes neurological deficits. Here we introduce a new strategy combining mesenchymal stromal cells (MSCs) and ex vivo hepatocyte growth factor (HGF) gene transferring with a multimutated herpes simplex virus type-1 vector in a rat transient middle cerebral artery occlusion (MCAO) model. Gene-transferred MSCs were intracerebrally transplanted into the rats' ischemic brains at 2h (superacute) or 24 h (acute) after MCAO. Behavioral tests showed significant improvement of neurological deficits in the HGF-transferred MSCs (MSC-HGF)-treated group compared with the phosphate-buffered saline (PBS)-treated and MSCs-only-treated group. The significant difference of infarction areas on day 3 was detected only between the MSC-HGF group and the PBS group with the superacute treatment, but was detected among each group on day 14 with both transplantations. After the superacute transplantation, we detected abundant expression of HGF protein in the ischemic brain of the MSC-HGF group compared with others on day 1 after treatment, and it was maintained for at least 2 weeks. Furthermore, we determined that the increased expression of HGF was derived from the transferred HGF gene in gene-modified MSCs. The percentage of apoptosis-positive cells in the ischemic boundary zone (IBZ) was significantly decreased, while that of remaining neurons in the cortex of the IBZ was significantly increased in the MSC-HGF group compared with others. The present study shows that combined therapy is more therapeutically efficient than MSC cell therapy alone, and it may extend the therapeutic time window from superacute to acute phase.
Positron Emission Tomography of Monoaminergic Vesicular Binding in Aging and Parkinson Disease
Authors: Bohnen Nicolaas I , Albm Roger L , Koeppe Robert A , Wernette Kristine A , Kilbourn Michael R , Minoshima Satoshi , Frey Kirk A
Published: January 2006

The type-2 vesicular monoamine transporter (VMAT2) might serve as an objective biomarker of Parkinson disease (PD) severity. Thirty-one subjects with early-stage PD and 75 normal subjects underwent continuous intravenous infusion of (+)-[11C]dihydrotetrabenazine (DTBZ) and positron emission tomography (PET) imaging to estimate the striatal VMAT2 binding site density with equilibrium tracer modeling. Parkinson disease patients were evaluated clinically in the practically defined ‘off’ state with the Unified Parkinson Disease Rating Scale (UPDRS), the Hoehn and Yahr Scale (HY), and the Schwab and England Activities of Daily Living Scale (SE). In normal subjects there was age-related decline in striatal DTBZ binding, approximating 0.5% per year. In PD subjects, specific DTBZ binding was reduced in the caudate nucleus (CD; −44%), anterior putamen (−68%), and posterior putamen (PP; −77%). The PP-to-CD ratio of binding was reduced significantly in PD subjects. Dihydrotetrabenazine binding was also reduced by approximately 50% in the PD substantia nigra. Striatal binding reductions correlated significantly with PD duration and SE scores, but not with HY stage or with UPDRS motor subscale (UPDRSIII) scores. Striatal and midbrain DTBZ binding was asymmetric in PD subjects, with greatest reductions contralateral to the most clinically affected limbs. There was significant correlation between asymmetry of DTBZ binding and clinical asymmetry measured with the UPDRSIII. In HY stage 1 and 1.5 subjects ( n = 16), PP DTBZ binding contralateral to the clinically unaffected body side was reduced by 73%, indicating substantial preclinical nigrostriatal pathology in PD. We conclude that (+)-[11C]DTBZ-PET imaging displays many properties necessary of a PD biomarker.
Electron Paramagnetic Resonance-Guided Normobaric Hyperoxia Treatment Protects the Brain by Maintaining Penumbral Oxygenation in a Rat Model of Transient Focal Cerebral Ischemia
Authors: Liu Shimin , Liu Wenlan , Ding Wei , Miyake Minoru , Rosenberg Gary A , Liu Ke Jian
Published: January 2006

Oxygen therapy for ischemic stroke remains controversial. Too much oxygen may lead to oxidative stress and free radical damage while too little oxygen will have minimal therapeutic effect. In vivo electron paramagnetic resonance (EPR) oximetry, which can measure localized interstitial partial oxygen (pO2), can monitor penumbral changes of pO2. Therefore, we used EPR to study the effects of oxygen therapy in a rat model of 90-mins middle cerebral artery occlusion (MCAO). We found that 95% normobaric O2 given during ischemia was able to maintain penumbral interstitial pO2 levels close to the preischemic value while it may cause a two-fold increase in penumbral pO2 level if given during reperfusion. Elevation of the penumbra pO2 to preischemic physiologic level during MCAO significantly reduced infarction volume, improved neurologic function, decreased the generation of reactive oxygen species (ROS), and reduced matrix metalloproteinase (MMP)-9 expression and caspase-8 cleavage in the penumbra tissue of rats brain treated with oxygen. These results suggest that maintaining penumbral oxygenation by normobaric oxygen treatment during ischemia lead to neuroprotection, which is further reflected by the decreased production of ROS, MMP-9, and caspase-8.
The low-lying electronic states of nickel cyanide and isocyanide: A theoretical investigation
Authors: Paul Ankan , Yamaguchi Yukio , Schaefer Henry F. , Peterson Kirk A.
Published: January 2006

At different levels of coupled cluster theory optimum structures, energetics, and harmonic vibrational frequencies for several low-lying doublet and quartet electronic states of linear NiCN and NiNC were studied using four contracted Gaussian basis sets, ranging from Ni[6s5p4d2f], C∕N[4s3p2d] to Ni[8s7p5d3f2g1h], C∕N[5s4p3d2f1g]. The most reliable predictions were obtained with a relativistic Douglas-Kroll restricted open-shell-based coupled cluster method including singles, doubles, and perturbative triple excitations [DK-R/UCCSD(T)]. This level of theory was used in conjunction with correlation-consistent polarized valence Douglas-Kroll recontracted quadruple-zeta basis sets (cc-pVQẔDK). The energetic ordering of the electronic states of NiCN is predicted to be Δ2<Σ+2<Π2<Δ4<Π4 and that of NiNC is Δ2≈Σ+2<Π2<Δ4<Π4<Σ−4. Our theoretical investigation supports the assignment of the ground-state term symbol, the Ni–C stretching frequency, and the bending frequency for the ground electronic state of NiCN by Kingston et al. [J. Mol. Spectrosc. 215, 106 (2002)] and by Sheridan and Ziurys [J. Chem. Phys. 118, 6370 (2003)]. The predicted structure of the Δ2 ground state of NiCN, re(Ni–C)=1.822Å and re(C–N)=1.167Å, at DK-R/UCCSD(T)/cc-pVQẔDK shows excellent agreement with the experimentally determined Ni–C bond length of 1.826Å and less satisfactory agreement for the C–N bond length of 1.153Å [J. Chem. Phys. 118, 6370 (2003)]. It is also concluded that the metal-to-ligand π back donation is weak or negligible. Additionally, we found that on the Δ2 surface the linear cyanide isomer lies lower in energy than the linear isocyanide isomer by 12.2kcalmol−1.
Transient gratings generated by particulate suspensions: The uniformly irradiated sphere and the point source
Authors: Frez Clifford , Calasso Irio G. , Diebold Gerald J.
Published: January 2006

Expressions for the time dependence of the state variables in a transient grating experiment carried out on suspensions of particles can be determined by integration over space of the solutions for the temperature and photoacoustic pressure for a single particle. The method relies on independent computation of the thermal and acoustic modes of wave motion which are combined to give the temperature, pressure, and density in the grating as a function of time. Calculations are given for the uniformly irradiated droplet and the point source, the latter including the effects of a temperature-dependent thermal expansion coefficient. Transient grating experiments are reported in colloidal Pt that show features described in the calculation.
Reconciling semiclassical and Bohmian mechanics. III. Scattering states for continuous potentials
Authors: Trahan Corey , Poirier Bill
Published: January 2006

In a previous paper [B. Poirier, J. Chem. Phys. 121, 4501 (2004)] a unique bipolar decomposition Ψ=Ψ1+Ψ2 was presented for stationary bound states Ψ of the one-dimensional Schrödinger equation, such that the components Ψ1 and Ψ2 approach their semiclassical WKB analogs in the large-action limit. The corresponding bipolar quantum trajectories, as defined in the usual Bohmian mechanical formulation, are classical-like and well behaved, even when Ψ has many nodes or is wildly oscillatory. A modification for discontinuous potential stationary scattering states was presented in a second, companion paper [C. Trahan and B. Poirier, J. Chem. Phys.124, 034115 (2006), previous paper], whose generalization for continuous potentials is given here. The result is an exact quantum scattering methodology using classical trajectories. For additional convenience in handling the tunneling case, a constant-velocity-trajectory version is also developed.
Sample size, position, and structure effects on magnetization measurements using second-order gradiometer pickup coils
Authors: Stamenov P. , Coey J. M. D.
Published: January 2006

Errors arising from finite sample size and structure effects, sample displacement, background noise level, and other imperfections, often confronted in high-sensitivity magnetization measurements, are characterized. A semianalytical finite-element analysis code is developed in MATHCAD, MAPLE, and C to simulate the response of a second-order gradiometer pickup coil assembly (for example, the Quantum Design magnetic property measurement system MPMS® XL). The flux integrals are computed for given sample shape, orientation, and position, arbitrary direction of the magnetization, and magnetic moment spatial distribution, and their axial distributions are analyzed using all three standard regression procedures (geometrical average, linear regression, nonlinear least squares). Procedures are described for recovering the component of the magnetic moment orthogonal to the axis of the gradiometer, estimating the axial projection of the total dipole density, and reconstructing the on-axis magnetization profile by various types of deconvolution. The procedures are illustrated with reference to measurements of ferromagnetic thin films on diamagnetic substrates, diamagnetic wires, and discreet distributions of magnetic moments.
General-model-space state-universal coupled-cluster methods for excited states: Diagonal noniterative triple corrections
Authors: Li Xiangzhu , Paldus Josef
Published: January 2006

The recently developed multireference, general-model-space, state-universal coupled-cluster approach considering singles and doubles (GMS SU CCSD) has been extended to account perturbatively for triples, similar to the ubiquitous single-reference CCSD(T) method. The effectiveness of this extension in handling of excited states and its ability to account for the static and nondynamic correlation effects when considering spin- and/or space-symmetry degenerate levels within the spin-orbital formalism is examined on the example of low-lying excitation energies of the C2, N2, and CO molecules and a comparison is made with the (N,N)-CCSD method used for the same puropose. It is shown that while the triple corrections are very effective in improving the absolute energies, they have only a modest effect on the corresponding excitation energies, which may be even detrimental if both the ground- and excited-state levels cannot be given a balanced treatment. While the triple corrections help to avoid the symmetry-breaking effects arising due to the use of the spin-orbital formalism, they are much less effective in this regard than the (N,N)-CCSD approach.
Elastic and charge transfer processes in H++CO collisions
Authors: Dhilip Kumar T. J. , Saieswari A. , Kumar Sanjay
Published: January 2006

Proton and hydrogen atom time-of-flight spectra in collision energy range of Etrans=9.5–30eV show that the endoergic charge transfer process in the H++CO system is almost an order of magnitude less probable than the elastic scattering [G. Niedner-Schatteburg and J. P. Toennies, Adv. Chem. Phys. LXXXII, 553 (1992)]. Ab initio computations at the multireference configuration interaction level have been performed to obtain the ground- and several low-lying excited electronic state potential energy curves in three different molecular orientations namely, H+ approaching the O-end and the C-end (collinear), and H+ approaching the CO molecule in perpendicular configuration with fixed CO internuclear distance. Nonadiabatic coupling terms between the ground electronic state (H++CO) and the three low-lying excited electronic states (H+CO+) have been computed and the corresponding diabatic potentials have been obtained. A time-dependent wavepacket dynamics study is modeled first involving only the ground and the first excited states and then involving the ground and the three lowest excited states at the collision energy of 9.5eV. The overall charge transfer probability have been found to be ≈20%–30% which is in qualitative agreement with the experimental findings.
Quantum-mechanical evaluation of the Boltzmann operator in correlation functions for large molecular systems: A multilayer multiconfiguration time-dependent Hartree approach
Authors: Wang Haobin , Thoss Michael
Published: January 2006

It is shown that the Boltzmann operator in time correlation functions for complex molecular systems can be evaluated in a numerically exact way employing the multilayer formulation of the multiconfiguration time-dependent Hartree theory in combination with Monte Carlo importance sampling techniques. The performance of the method is illustrated by selected applications to photoinduced intervalence electron transfer reactions in the condensed phase. Furthermore, the validity of approximate schemes to evaluate the Boltzmann is discussed.
Molecular-dynamics simulations and master-equation description of a chemical wave front: Effects of density and size of reaction zone on propagation speed
Authors: Hansen J. S. , Nowakowski B. , Lemarchand A.
Published: January 2006

We compare the master-equation description and molecular-dynamics simulations of a chemical wave front. We find that the front propagation speed depends on the number of particles in the reaction zone. For the master equation the dependence follows the well-known logarithmic prediction obtained when introducing a cutoff into the macroscopic reaction-diffusion equation. The molecular-dynamics simulations reveal that the logarithmic law is compromised for dense fluids.
Covariant irreducible parametrization of electromagnetic fields in arbitrary space-time
Authors: Sundkvist David
Published: January 2006

We present a new unified covariant description of electromagnetic field properties for an arbitrary space-time. We derive a complete set of irreducible components describing a six-dimensional electromagnetic field from the Maxwell and metric tensors using the symmetry group SL(2,C). For the special case of a flat space-time metric the components are shown to correspond to the scalar invariants of the electromagnetic field, the energy-momentum-stress tensor and in addition, three new tensors expressing physical observables of rank two and four, respectively. We make a physical interpretation of one of the new rank two tensor as describing a classical intrinsic spin of the electromagnetic field.
Virtual Rogowskii loops for the evaluation of plasma and in-vessel eddy currents in the KSTAR tokamak
Authors: Tsaun S. , Jhang Hogun
Published: January 2006

A simple but effective method is proposed for the estimation of plasma and in-vessel eddy currents in the KSTAR device. It is based on the prescribed contour integrals of the tangential magnetic fields measured by magnetic probes. It is shown that the method can estimate the plasma current in 0.33% accuracy. It is also found that the total in-vessel eddy current can be determined with accuracy within a few kiloamperes regardless of plasma conditions.
Quantum dot formation and dynamic scaling behavior of SnO2 nanocrystals induced by pulsed delivery
Authors: Chen Z. W. , Lai J. K. L. , Shek C. H.
Published: January 2006

Quantum dot formation and dynamic scaling behavior of SnO2 nanocrystals in coalescence regime for growth by pulsed-laser deposition is explored experimentally and theoretically, and the same is compared with that for continuous vapor deposition such as molecular-beam epitaxy. Using high-resolution transmission electron microscopy, unusual quantum dots of SnO2 nanocrystals are studied. We present kinetic Monte-Carlo simulations for pulsed-laser deposition in the submonolayer regime and give a description of the island distance versus pulse intensity. We found that the scaling exponent for pulsed-laser deposition is 1.28±0.03, which is significantly lower as compared to that for molecular-beam epitaxy (1.62±0.03). Theoretical simulations reveal that this attractive difference can be pursued to the large fraction of multiple droplet coalescence under pulsed vapor delivery.
Rotating sample magnetometer for precise, real time differential measurements
Authors: Zawilski Bartosz M. , Maillard Denis L. E. , Geoffroy Olivier , Dufeu Didier
Published: January 2006

In this paper we present the development of a rotating sample magnetometer (RSM) for real time differential magnetic moment measurement. The high accuracy and simplicity of the described apparatus allow reliable and fast magnetic characterization of samples with small magnetic moment. This performances (about 10−10Am2 with our prototype), associated with the low cost of the apparatus, should make it a very promising tool for thin magnetic film characterization.
Efficiency improvement of phosphorescent organic light-emitting diodes using semitransparent Ag as anode
Authors: Peng H. J. , Zhu X. L. , Sun J. X. , Yu X. M. , Wong M. , Kwok H. S.
Published: January 2006

The emission efficiency in an organic light-emitting diode (OLED) based on fac tris(phenyl pyridine)iridium [Ir(ppy)3] is greatly improved using a semitransparent Ag anode. With surface modification of the Ag anode, excellent light coupling and hole injection properties can be realized. The Ag-based OLED exhibits a maximum current efficiency of 81cd∕A and a power efficiency of 79lm∕W, compared with 46cd∕A and 39lm∕W for an indium-tin oxide anode device, respectively.
Electrodeposition of iron core-shell nanoparticles on a H-terminated Si(100) surface
Authors: Zhao L. Y. , Eldridge K. R. , Sukhija K. , Jalili H. , Heinig N. F. , Leung K. T.
Published: January 2006

Iron core-shell nanoparticles with different morphologies were obtained on a H-terminated Si(100) surface for the first time by electrodeposition at different FeCl3 concentrations. At 10 mM, near-monosized and uniformly distributed oval-shaped nanorod Fe particles (130nmlength×25nmdiameter), with a mixed FeOOH and FeO shell, have been obtained. At 0.1 mM, spherical Fe nanoparticles (6–40 nm diameter) with a broader size distribution and a mixed Fe2O3 and FeO shell were observed. The morphologies and compositions of these two types of Fe core-shell nanoparticles could be easily manipulated to provide magnetic properties of potential industrial interest.
Ion scattering and electron spectroscopy of the chemical species at a HF-prepared Si(211) surface
Authors: Jaime-Vasquez M. , Martinka M. , Groenert M. , Dinan J.
Published: January 2006

The species and the nature of their chemical bonds at the surface of a hydrogen-terminated Si(211) wafer were characterized using temperature desorption spectroscopy, ion scattering spectroscopy, and electron spectroscopy. The surface region is dominated by monohydride species with dihydrides present in small amounts. Fluorine is distributed across the top layer as largely a physisorbed species to the Si substrate. Low-energy He+3 ions remove the H and F species with only minimal damage to the underlying region.
Generation of misfit dislocations and stacking faults in supercritical thickness strained-Si∕SiGe heterostructures
Authors: Kimura Y. , Sugii N. , Kimura S. , Inui K. , Hirasawa W.
Published: January 2006

Defects in the supercritical thickness strained-Si layer grown on a fully relaxed SiGe buffer layer were investigated by atomic force microscopy (AFM) and transmission electron microscopy (TEM). The AFM observation of chemically etched surfaces showed that etch pits having a crosshatch pattern due to misfit dislocations decrease and segments and deep valley profiles increase with an increase in the strain energy of the Si. We found that the segment corresponds to an extended dislocation, of which a 30° partial is in the strained-Si layer and a 90° partial is in the SiGe layer, and the deep valley corresponds to a stacking fault found by a high-resolution TEM observation. A model of the generation of the stacking fault related to development of the misfit dislocation is also discussed here.
Homogeneous Commercial Property Market Groupings and Portfolio Construction in the United Kingdom
Authors: Hamelink Foort , Hoesli Martin , Lizieri Colin , MacGregor Bryan D
Published: January 2006

Property portfolios are traditionally constructed by diversifying across geographical areas, property types, or a combination of both. In the United Kingdom it is normal practice to use regions rather than towns or local market areas as the geographical divisions. The authors use cluster analysis to construct homogeneous groups from 157 UK local markets, by means of commercial property returns. The results show strong property-type dimensions and only very broad geographical dimensions in the clusters. These clusters are found, in general, to have temporal stability with changes in cluster membership being explained by the changing economic geography of the United Kingdom. The cluster-derived groupings are used to derive efficient investment frontiers and are compared with frontiers based on conventional heuristic groupings. It is shown that strategies based on parsimonious cluster-based groupings, appropriate for smaller investors, generate results that are comparable with those of conventional groupings and capture the main drivers of property performance.
Networks, Keiretsu, and Locations of the Japanese Electronics Industry in Asia
Authors: Aoyama Yuko
Published: January 2006

It has been assumed that industrial networks, particularly of keiretsu-based organizations, play the major role in dictating the formation of industrial agglomerations for Japanese investment in overseas locations. In this paper, I examine whether currently available establishment data on Japanese firms in Asia confirm this tendency for the electronics industry. The data show that actual reliance on keiretsu networks in Asia is relatively low, and keiretsu relationships are more likely to reflect a strong relationship at the global level, rather than relationships with suppliers within host countries. This result poses questions on the assumptions of network-based industrialization affecting locations of foreign direct investment.
Growth, Disintegration, and Decentralization: The Construction of Taiwan's Industrial Networks
Authors: Buck Daniel
Published: January 2006

Manufacturing based on networks of small family firms is widely regarded to have been integral to Taiwan's development success. Many studies discuss the social embeddedness, flexibility, efficiency, and competitive advantage of these networks, but there have been few systematic attempts to theorize their origins. A processual analysis of the changing spatial structure of Taiwan's industry, in its social, political, and historical contexts, reveals that Taiwan's concentrated industries of the 1950s did not disintegrate into smaller firms. Rather, there was a proliferation of new rural firms after the mid-1960s. The construction of a disintegrated, decentralized, and networked structure was driven by the contingent actions of rural household entrepreneurs, pursuing strategies of social reproduction, under circumstances resulting from, among other things, an extensive land-reform program and redistributive agricultural policies. Transactions costs and neo-Weberian authority approaches elucidate important factors, but fail to explain the creation of this new class of petty entrepreneurs, and how the conditions of their entrance shaped the networked form of organization they created. Furthermore, their actions did not result from state-led development policies as much as they were the unintended consequences of state policies, preceding by several years government efforts to support the growth of small firms and rural industry. Finally, urban-push explanations assume a passive countryside, thus ignoring the ways rural actors energetically created new structures of production out of the resources at hand.
Organizing the Indonesian Clothing Industry in the Global Economy: The Role of Business Networks
Authors: Dicken Peter , Hassler Markus
Published: January 2006

In a relatively short period of time, Indonesia has become a significant centre of clothing production within the global economy. Its overall growth can be explained primarily by the intersection between two sets of political-economic processes: those operating at the global level of the industry in general and those specific to Indonesia itself. Within these general processes, we explore the particular organizational mechanisms through which this growth has occurred. Detailed field evidence shows how the Indonesian clothing industry is deeply embedded in production networks which connect domestic producers with international networks of production and distribution, notably those organized by Korean, Taiwanese, US, and European firms. Although such networks are generally consistent with Gereffi's concept of the buyer-driven global commodity chain, we show that the precise shape and the driver of the company-specific production networks in Indonesia are highly dependent on the specific market being served. Finally, brief attention is given to the potential impact of the current East Asian economic crisis on Indonesian clothing firms.
Embedding Foreign Affiliates in Transnational Business Networks: The Case of Hong Kong Firms in Southeast Asia
Authors: Yeung Henry Wai-Chung
Published: January 2006

The author aims to examine the nature and organisation of transnational business networks. From an empirical study of some 111 parent Hong Kong transnational corporations (TNCs) and 63 of their foreign affiliates in Southeast Asia, he argues that the role and functions of TNC affiliates are critically dependent on their embeddedness in transnational business networks. These transnational business networks can be organised either within TNCs (intrafirm) or with local firms (interfirm). This network embeddedness of TNC affiliates is socially organised and can be strategically deployed to facilitate the extension of network associations through time and space. Two detailed case studies of business networks of Hong Kong TNCs (HKTNCs) in Southeast Asia present several interesting illustrations. First, the strategic strength and spatial reach of intrafirm networks determine the competitive advantage of Hong Kong TNCs in the regional economy. Better integration and regional coverage are the winning strategies of Hong Kong firms in Southeast Asia. Second, the embeddedness of foreign affiliates in the business networks of HKTNCs are socially constructed. Personal relationships and business association among leading actors in HKTNC networks provide the underlying organising principles of such network formation. Third, the functions and contributions of local Southeast Asian affiliates to overall group performance are related to their access to local business and other forms of interfirm networks. Local affiliates with strong networking capabilities tend to receive more support and coordination from parent TNCs. In the concluding section the author offers some implications for recent developments in network theory in economic geography and geographies of Chinese business networks in Asia.
Scratching the Surface of Collaborative and Associative Governance: Identifying the Diversity of Social Action in Institutional Capacity Building
Authors: Phelps Nicholas A , Tewdwr-Jones Mark
Published: January 2006

Recent work on ‘collaborative planning’ has concentrated on applying Habermas's work on communicative action to the realm of urban and regional governance. This work has its parallels in other disciplines, notably geography, where institutional capacity building has been considered as part of local systems of governance. Both bodies of work are premised to a degree on the rationality of communication. Habermas contrasted his ideas on the possibilities for communicative action with the widespread presence of ‘strategic behaviour’ in social relations. The dual nature of governance as both an institutional and a political activity means that consideration of such strategic forms of behaviour is essential to a deeper understanding of the nature of collaborative and associative forms of governance and their outcomes. What social scientists refer to as ‘teleological/strategic action’, ‘normatively regulated action’, and ‘dramaturgical action’ together with communicative action are all integral to collaborative governance. In this paper, we consider examples of the manner in which institutional capacity has been exercised in attempts to attract a major inward investment project into the United Kingdom. The example illustrates the range of social actions that are present beneath the surface of collaborative and associative governance. More specifically, our example highlights the structuring of institutional and organisational interactions through the strategic behaviour of a dominant local organisation.
Intersecting Global and Local Influences in Urban Place Promotion: The Case of Christchurch, New Zealand
Authors: Schöllmann Andrea , Perkins Harvey C , Moore Kevin
Published: January 2006

The promotion of cities as tourism destinations is seen as a way to enable growth. This promotion involves the projection of selective imagery to specific target groups and often includes the physical reshaping of places to fit a promotable image. Attempts to understand these processes have often focused on one of two approaches: a global perspective stressing the consumptive nature of the tourist gaze and the resultant commodification of place at the local level; and a local perspective emphasising difference and uniqueness. In this paper the authors outline an investigation into the promotion of the city of Christchurch, New Zealand. They found that local place-promotional messages are a product both of global economic forces, which stimulate the growth of tourism, and of a local search for identity. The local ‘sense of place’, as constructed in place-promotional imagery, is constantly reviewed and reflects changing social relationships in place and through time. Christchurch, therefore, is not simply promoted in the image of tourism with, as it is often claimed, the inevitable commodification of place and destruction of meaning. Local claims to uniqueness are an expression of the current social relationships in place, which construct selective histories of the past based on ideas of the present that are linked to a search for identity both at the local and at the national level.
Social and Cultural Relations in Economic Action: The Embeddedness of Food Security in Rural Malawi Amidst the AIDS Epidemic
Authors: Mtika Mike Mathambo
Published: January 2006

In its prescription of how food security among rural households can be attained and how problems such as AIDS can be addressed, the neoclassical utiliarian view envisions individual house-holds making atomistic decisions in the use of their resources, goods, and services (entitlements). In exploring the effect of illness and death on household food security in rural Malawi amidst the AIDS epidemic, I find that the embeddedness view explains more convincingly how rural households secure their food supply and deal with illness and death. This view suggests that individual households' use of their entitlements indeed contributes to household food security and the fight against illness and death, but that such use is shaped by the entitlement system that embodies collective beliefs, rules, expectations, and obligations. Social and cultural relations between households, anchored in the entitlement system, enable households to share their entitlements through reciprocity and redistribution, thereby contributing to collective food security and diffusing the burden of illness and death across households. Rural Malawians are thus not isolated actors envisioned by the utilitarian view but social actors who constantly engage in negotiations with each other, sharing their entitlements, and thus collectively securing their food supply and diffusing burdens. Food security then gets compromised when burdens reach a threshold that fractures social and cultural ties thus disabling households from sharing entitlements. AIDS is a threat to food security in rural Malawi because of its potential to make the spread of illness and death burdens so extensive that households would be unable to share their entitlements.
Production Location under Technology Uncertainty
Authors: Tan Lin-Ti , Hsu Song-Ken
Published: January 2006

In this paper we examine the implications of technology uncertainty for production location in a general setting, in which the location and production decisions are determined ex ante and a general specification of technology uncertainty is adopted. In addition, to examine the endpoint optimality issue, we also provide comparative static results which are novel in the literature. Moreover, the exhaustion of information contained in the second-order optimal conditions in deriving the conditions for endpoint optimality differentiates our analysis from previous works.
Agglomeration and Firm Performance: Economies of Scale, Localisation, and Urbanisation among Swedish Export Firms
Authors: Malmberg Anders , Malmberg Bo , Lundequist Per
Published: January 2006

In the 1990s, there has been an increase in interest in the spatial agglomeration of similar and related firms and industries. The recent literature is, however, marked by a lack of balance between theoretical development and empirical validation of the importance of agglomeration economies. Our aim in this paper is to redress the balance by assessing empirically the impact of various types of agglomeration economies on export performance. Our study is based on a unique data set including all Swedish export firms. We find that localisation economies are not as important as recent theoretical contributions on industrial districts, new industrial spaces, and innovative milieus have led us to believe. Instead, traditional scale economies, together with urbanisation economies, have a larger effect on export performance.
Statistical Tests for Spatial Nonstationarity Based on the Geographically Weighted Regression Model
Authors: Leung Yee , Mei Chang-Lin , Zhang Wen-Xiu
Published: January 2006

Geographically weighted regression (GWR) is a way of exploring spatial nonstationarity by calibrating a multiple regression model which allows different relationships to exist at different points in space. Nevertheless, formal testing procedures for spatial nonstationarity have not been developed since the inception of the model. In this paper the authors focus mainly on the development of statistical testing methods relating to this model. Some appropriate statistics for testing the goodness of fit of the GWR model and for testing variation of the parameters in the model are proposed and their approximated distributions are investigated. The work makes it possible to test spatial nonstationarity in a conventional statistical manner. To substantiate the theoretical arguments, some simulations are run to examine the power of the statistics for exploring spatial nonstationarity and the results are encouraging. To streamline the model, a stepwise procedure for choosing important independent variables is also formulated. In the last section, a prediction problem based on the GWR model is studied, and a confidence interval for the true value of the dependent variable at a new location is also established. The study paves the path for formal analysis of spatial nonstationarity on the basis of the GWR model.
European Economic Integration and Urban Inequalities in Western Europe
Authors: McCarthy Linda
Published: January 2006

Recent processes of European integration have influenced profoundly the fortunes of cities across Western Europe. Although some cities have benefited, others have been impacted adversely. Income inequalities result from economic growth differentials occurring between different cities over time. The theoretical literature differs on whether increased integration promotes or reduces income disparities. The European Union (EU) assumes that rising inequalities will impair EU growth and lead to even greater disparities. Empirical analysis has concentrated on the EU-defined regions because of problems of urban data availability and comparability. Using regional data, I identified that the overall level of inequalities changed little for the metropolitan regions between the early 1980s and the early 1990s. Urban disparities were cyclical—decreasing during strong EU growth and increasing in slower growth years. Factors outside direct local government control, including relative location within Europe, reinforced the traditional strong-core—weak-periphery spatial pattern of development. I argue that additional factors specific to cities, such as limited EU urban policy and funding, contributed to overall higher and more sharply rising inequalities since the late 1980s for cities compared with regions. The positive linear relationship between levels of national income and urban disparities has implications for economic polarization within richer member states and for EU efforts to reduce inequalities by raising the level of development in poorer countries.
An Example to Us All: Child Development and Identity Construction in Early 20th-Century Playgrounds
Authors: Gagen Elizabeth A
Published: January 2006

At the turn of the 20th century, children's play came under new and heightened scrutiny by urban reformers. As conditions in US cities threatened traditional notions of order, reformers sought new ways to direct urban-social development. In this paper I explore playground reform as an institutional response that aimed to produce and promote ideal gender identities in children. Supervised summer playgrounds were established across the United States as a means of drawing children off the street and into a corrective environment. Drawing from literature published by the Playground Association of America and a case study of playground management in Cambridge, MA, I explore playground training as a means of constructing gender identities in and through public space. Playground reformers asserted, drawing from child development theory, that the child's body was a conduit through which ‘inner’ identity surfaced. The child's body became a site through which gender identities could be both monitored and produced, compelling reformers to locate playgrounds in public, visible settings. Reformers' conviction that exposing girls to public vision threatened their development motivated a series of spatial restrictions. Whereas boys were unambiguously displayed to public audiences, girls' playgrounds were organised to accommodate this fear. Playground reformers' shrewd spatial tactics exemplify the ways in which institutional authorities conceive of and deploy space toward the construction of identity.
Institutionalising Technologies: Masculinities, Femininities, and the Heterosexual Economy of the IT Classroom
Authors: Holloway Sarah L , Valentine Gill , Bingham Nick
Published: January 2006

Geographers' renewed interest in institutions reflects traditional concerns with the way institutions can shape geographies and a more recent interest in the ways geographies are important in shaping institutions. In this paper the authors build on this second strand of work and are specifically concerned with children's use of new information and communications technologies in schools. The authors suggest that multilayered institutional cultures, which are shaped by official school policy, teacher practice, and pupil culture, are exceedingly important in shaping distinct cultures of computing in (and within) the case-study schools. The highly gendered character of these institutional cultures is reflected in the very different attitudes of male and female pupils to computers and in the patterns of use which generally favour boys rather than girls. These are negotiated through competing masculinities and femininities in the classroom context, gender identities which are played out through normative understandings of heterosexuality. The authors conclude that we may indeed characterise institutions as ‘precarious geographical achievements’, as suggested by Parr and Philo. Schools are embedded within wider places, are important sites for the negotiation of gender and sexual identities, and, as spaces, are in part shaped through our notions of gender and sexuality. This achievement is only precarious as institutions are not forever solidified in their current form but are open to change, both inadvertently and through the concerted actions of individuals.
The Hidden and Emerging Spaces of Rural Homelessness
Authors: Cloke Paul , Widdowfield Rebekah C , Milbourne Paul
Published: January 2006

In this paper we explore key issues bound up with the existence of homelessness in rural England. Attention is directed to a variety of factors that combine to reduce the visibility or even deny the presence of homelessness in rural spaces. We suggest that the complexities of rural homelessness are such that it may only become visible in particular spaces; spaces that tend to be constructed as nonrural. The paper begins with a critical discussion of spatialised representations of homelessness and privileged constructions of rural spaces in England which together act to obscure visibilities of rural homelessness in a range of discursive environments. We then move on to examine the ways in which such representations and constructions impact on and connect with local experiences of rural homelessness by drawing on some key findings from recent research. Here we consider three main issues concerning visibilities and invisibilities of homelessness in rural spaces: first, visibilities accorded to certain manifestations of rural homelessness through discourses of official statistics; second, a series of invisibilities associated with localised representations and experiences of homelessness in rural areas; and, finally, the ways in which rural homelessness emerges and becomes obvious in spaces that may be described as nonrural.
The Cultural Role of Universities in the Community: Revisiting the University—Community Debate
Authors: Chatterton Paul
Published: January 2006

In this paper the interaction between the university and the community is addressed. Whilst previous work has concentrated on the economic roles of universities in the community, insufficient attention has been paid to their cultural roles. Drawing upon fieldwork undertaken in Bristol, United Kingdom, I highlight a number of cultural roles which universities undertake in the community. In particular I outline the historical development of the cultural role of the university through a shift from the high-cultural role of the elite university to a broader cultural role for the contemporary mass university. A new environment for universities, including the declining influence of national structures, the interplay of processes of localisation and globalisation, and the emergence of new regional governance structures in Britain, is reshaping the cultural relationship between the university and the community and is opening up new possibilities for the creation of a closer, and more equal, relationship between them. This in turn could open up new possibilities for a greater sense of a shared public culture and address the evolving idea of the university. However, concerns are raised in relation to how these are affected by the introduction of globalisation practices and discourses into the university.