bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polyelectrolyte spin assembly: Influence of ionic strength on the growth of multilayered thin films
Authors: Lefaux Christophe J. , Zimberlin Jessica A. , Dobrynin Andrey V. , Mather Patrick T. 
Published: August 2004

AbstractLayer‐by‐layer (LbL) assembly of polymer electrolyte multilayers is now a well‐established method for the fabrication of thin films by sequential adsorption of alternating layers of oppositely charged polyelectrolytes. Most commonly, such adsorptions have been from quiescent solutions of varying ionic strength and pH. Here, we report results on an alternative processing route for the achievement of polymeric multilayer assemblies of poly(sodium‐4‐styrene sulfonate) and poly(allylamine hydrochloride) that utilizes conventional spin coating. We investigated and describe herein the dependence of multilayer film buildup on solution ionic strength for comparison with similar dependence in quiescent adsorption. Using UV‐Vis spectroscopy we monitored the growth of the multilayered films, while with Atomic Force Microscopy (AFM) we examined the surface features and measured coating thicknesses at different salt concentrations. AFM and UV‐Vis data reveal two regimes of behavior with increasing salt: strong salt‐dependence at low salt contents, and weak salt‐dependence for high salt contents. To explain this observation, we introduce the relevance of the dimensionless groupDe=τ, the local Deborah Number, to the problem. As ionic strength increases, τ increases so that spin‐assembly flow influences adsorbed conformation, and thus LbL growth rate. Our results indicate the ability to design and control polyelectrolyte multilayered structures prepared via spin assembly by varying solution properties that influence the conformation of deposited polymer chains. Additionally, our studies reveal the need for study of the fundamental mechanisms of polyelectrolyte adsorption within complex flow fields. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3654–3666, 2004
Engineering of a polymeric bacterial protein as a scaffold for the multiple display of peptides
Authors: Laplagne D.A. , Zylberman V. , Ainciart N. , Steward M. W. , Sciutto E. , Fossati C.A. , Goldbaum F. A. 
Published: August 2004

AbstractProtein assemblies with a high degree of repetitiveness and organization are known to induce strong immune responses. For that reason they have been postulated for the design of subunit vaccines by means of protein engineering. The enzyme lumazine synthase from Brucella spp. (BLS) is highly immunogenic, presumably owing to its homodecameric arrangement and remarkable thermodynamic stability. Structural analysis has shown that it is possible to insert foreign peptides at the ten amino terminus of BLS without disrupting its general folding. These peptides would be displayed to the immune system in a highly symmetric three‐dimensional array. In the present work, BLS has been used as a protein carrier of foreign peptides. We have established a modular system to produce chimeric proteins decorated with ten copies of a desired peptide as long as 27 residues and have shown that their folding and stability is similar to that of the wild‐type protein. The knowledge about the mechanisms of dissociation and unfolding of BLS allowed the engineering of polyvalent chimeras displaying different predefined peptides on the same molecular scaffold. Moreover, the reassembly of mixtures of chimeras at different steps of the unfolding process was used to control the stoichiometry and spatial arrangement for the simultaneous display of different peptides on BLS. This strategy would be useful for vaccine development and other biomedical applications. Proteins 2004. © 2004 Wiley‐Liss, Inc.
Density matrix force‐balance equation applied to He, Be, and Ne atoms and to almost‐spherical methane‐like molecules
Authors: Howard I. A. , March N. H. , Bartha F. , Ray A. K. , Zhang M.‐L. 
Published: August 2004

AbstractHolas and March (Phys Rev A 1995, 51, 2040) expressed the force −∇Vxc(r) associated with the exchange correlation potential Vxc(r) of density functional theory in terms of low‐order density matrices. Their result utilizes a many‐electron force balance equation for −∇Vext(r), where Vext(r) denotes the external potential. Here, insight is sought into this force‐balance equation by using both Hartree–Fock results and correlated electron calculations. Examples of two‐electron systems, including the exactly solvable model Hookean atom, are first set out, followed by treatments of the Be and Ne atoms. As a final, molecular, example, methane‐like systems are also more briefly studied, but now restricted solely to the Hartree–Fock level of approximation. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Overlap integrals for Dirac–Slater orbitals
Authors: Talman James D. 
Published: August 2004

AbstractThe problem of computing overlap integrals of Slater‐type orbitals on different centers for relativistic orbitals with a behavior of rs at the nuclei is considered. The integrals can be expressed as integrals in momentum space involving a spherical Bessel function jL(kR). The problem of the oscillatory behavior of jL(kR) at large kR can be eliminated by transforming the integral to a contour integral in the upper half‐plane. A method of carrying out the numerical integration is described and the number of integration points required for a large number of cases are given. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Modulation of bradykinin‐induced calcium changes in SH‐SY5Y cells by neurosteroids and sigma receptor ligands via a shared mechanism
Authors: Hong Weimin , Nuwayhid Samer J. , Werling Linda L. 
Published: August 2004

AbstractIn this study we investigated the effects of sigma receptor ligands and neurosteroids on bradykinin‐induced intracellular calcium concentration ([Ca2+]i) changes in SH‐SY5Y neuroblastoma cells. [Ca2+]i levels in cells loaded with fura‐2 were monitored with dual‐wavelength ratiometric fluorescence measurement. Submicromolar concentrations of bradykinin elicited [Ca2+]i responses with a fast rise followed by a slow decline in these cells. Preincubation of low micromolar concentrations of the neurosteroids pregnenolone, dehydroepiandrosterone (DHEA), or the prototypic sigma (σ) receptor agonist (+)pentazocine potentiated bradykinin‐induced [Ca2+]i changes in SH‐SY5Y cells. The σ receptor antagonist haloperidol blocked the enhancing effects on [Ca2+]i by (+)pentazocine or pregnenolone. Progesterone did not significantly affect the basal [Ca2+]i level or bradykinin‐induced [Ca2+]i changes in these cells. However, coincubation of progesterone with (+)pentazocine, pregnenolone, or DHEA reversed their potentiating effects. The antagonistic effects of haloperidol and progesterone on the potentiating effects of (+)pentazocine and pregnenolone suggested that these ligands might act through a common mechanism. We further showed that progesterone, pregnenolone, and DHEA competed for [3H](+)pentazocine binding in SH‐SY5Y cells with Ki values of 0.13 ± 0.03 μM, 0.98 ± 0.34 μM, and 5.2 ± 1.4 μM, respectively. Thus, the modulation of bradykinin‐induced [Ca2+]i changes by neurosteroids in these cells is likely due to their actions on σ receptors. Synapse 54:102–110, 2004. © 2004 Wiley‐Liss, Inc.
New international business perspectives on Pakistan
Authors: Khan Omar J. , Amine Lyn S. 
Published: August 2004

AbstractWhat image comes to mind when one thinks of Pakistan? Prior to the attacks of September 11, 2001, and the subsequent invasion of Afghanistan, many businesspeople had little information about this ancient land. Recently, Pakistan has come to the world's attention as a powerful ally in the U.S.‐led war against terrorism. Situated at the crossroads of the Middle East, Southeast Asia, China, and member nations of the former Soviet Union, Pakistan has long been a leading player in regional political and economic activity. This article presents some new perspectives on Pakistan as a market worthy of a closer look. We survey Pakistan's history and geography, as well as its sociocultural, political‐legal, economic, and competitive environments with a view to identifying new opportunities for foreign investors and global marketers. Current business trends and marketing opportunities are discussed, concluding with an outlook for future growth and development. Valuable insights are offered to businesspeople interested in doing business in Pakistan, a little‐studied but vitally important newly industrializing country (NIC) and big emerging market (BEM). © 2004 Wiley Periodicals, Inc.
Problems and challenges facing the islamic banking system in the west: The case of the UK
Authors: Karbhari Yusuf , Naser Kamal , Shahin Zerrin 
Published: August 2004

AbstractThis study investigates the main problems, challenges, and opportunities facing Islamic banking in the United Kingdom. The study reports the results of interviews that were undertaken with senior officials of several key financial institutions who have had many years of experience in dealing with Islamic banking. Our interviews revealed that, although by strict definition Islamic banks do not currently exist in the UK, London is one of the major centers for Islamic banking and finance. It is apparent that the experience of previously established Islamic institutions, such as Al‐Baraka, has made other institutions realize that it is possible to provide Islamic banking services in the UK under nonbanking regulations. The interviews also revealed that the main problem that Islamic banking faces in the UK is heterogeneous clients and potential clients. Moreover, regulatory hurdles, competition from conventional banks, and lack of adequately qualified and trained personnel exacerbate the situation. The study concludes by identifying opportunities such as e‐banking that may have a significant impact on the future of Islamic banking in the UK. © 2004 Wiley Periodicals, Inc.
An analysis of U.S. small and medium‐sized manufacturers' international business relationships
Authors: Leonidou Leonidas C. , Kaminarides John S. , Hadjimarcou John 
Published: August 2004

AbstractNotwithstanding the dominant role of the United States in world trade, little is known about the relationships between smaller indigenous manufacturers and their foreign customers and how these differ from domestic market relationships. Using data from a recent study among 201 U.S. small and medium‐sized enterprises (SMEs), the article reveals that (a) these firms tend to put much more emphasis on the domestic side of their business, while the foreign market receives secondary treatment; (b) the atmosphere governing their relational exchanges differs in the two types of markets, being relatively healthier in domestic business; and (c) their domestic business performance levels, although moderate, are significantly higher than those found in foreign markets. © 2004 Wiley Periodicals, Inc.
The AMBEGUJAS Phenomenon and Colour Constancy
Authors: Bergström Sten Sture 
Published: August 2004

The AMBEGUJAS phenomenon is a reversible flat figure that is spontaneously shifting between two apparent 3-D shapes—‘tile’ and ‘roof. 2-D perceptions have very rarely been reported. Tied to the shifts between the tile and roof shapes are remarkable changes of perceived colour. In our example, the tile appears to have orange (top half) and blue–green (bottom half) surface colours in white light. The roof appears grey but in an orange illumination and with a blue–green shadow. This phenomenon appears whether a grey display is presented in two coloured illuminations, or a chromatic display with two surface colours (orange and blue–green) is presented in white light. In the coloured illuminations the tile is an example of non-constancy, since its colours are non-veridical colour perceptions. The centre stripe of the display appears to have the same orange and blue–green colours as the lateral stripes but in a shadow. This seems like a colour constancy in a non-constancy situation. An alternative to the classical definition of colour constancy is discussed.
Dynamic first pass 3D EPI of the prostate: accuracy in tumor location
Authors: Storaas T. , Gjesdal K.‐I. , Svindland A. , Viktil E. , Geitung J. T 
Published: August 2004

Purpose: To evaluate the potential of dynamic contrast enhanced (DCE) 3D EPI in the location of prostate cancer. Material and Methods: A DCE 3D EPI scan was included in the magnetic resonance imaging protocol for prostate examination. Twenty‐eight patients who subsequently underwent radical prostatectomy were included in the study. T2‐weighted (T2W) Turbo Spin Echo (TSE) images were initially evaluated by two radiologists. Parametric images reflecting contrast enhancement were added and new evaluations performed. The results were compared with histology from resected specimens. Accuracies and interobserver agreements were calculated. Results: Interobserver agreement was κw=49±3% for the T2W technique and κw=30±3% for the combined techniques. No statistically significant advantages were found for location of tumor in the prostate or in the seminal vesicles by adding the DCE information. Conclusion: DCE 3D EPI did not improve tumor location compared with that of T2W TSE images. Further investigation is needed on how best to exploit the DCE technique.
Whole body magnetic resonance imaging in the diagnosis of parsonage turner syndrome
Authors: Ryan M. , Twair A. , Nelson E. , Brennan D. , Eustace S. 
Published: August 2004

Purpose: To describe magnetic resonance imaging (MRI) findings in patients with suspected Parsonage Turner syndrome and to emphasize the value of an additional whole body MR scan to improve specificity of this diagnosis. Material and Methods: Three patients with proven Parsonage Turner syndrome referred for conventional MRI of the shoulder girdle and additional whole body turboSTIR MRI were included for study. Results: In each case, imaging revealed edema in the muscles of the shoulder girdle. Whole body turboSTIR MRI scan confirmed localized unilateral changes in each case improving specificity and confidence in the diagnosis of Parsonage Turner syndrome in each case. Conclusion: Whole body turboSTIR MR imaging is a useful diagnostic tool in the evaluation of patients with suspected Parsonage Turner syndrome. Inclusion of the brain, neck, brachial plexus, and extremity musculature at whole body imaging allows differentiation from polymyositis and elimination of additional causes of shoulder girdle pain and weakness including gross lesions in the brain, neck, and brachial plexus by a single non‐invasive study.
Long‐term MRI findings in operated rotator cuff tear
Authors: Kyrölä K. , Niemitukia L. , Jaroma H. , Väätäinen U. 
Published: August 2004

Purpose: To describe magnetic resonance imaging (MRI) findings at long‐term follow‐up after rotator cuff (RC) tear using standard MRI sequences without fat saturation. Material and Methods: Twenty‐eight patients aged 55.8±7.6 underwent MRI examination 4.6±2.1 years after surgery for RC tear. Standard sequences in oblique coronal, oblique sagittal, and axial planes were obtained. The RC, including re‐tears and tendon degeneration, was independently evaluated by two observers. Thickness of the supraspinatus tendon and narrowing of the subacromial space were measured. The clinical outcome was evaluated with the Constant score and compared with the MRI findings. Results: The RC tear was traumatic in 18 (64%) patients and degenerative in 10 (36%). At follow‐up, 11 (39%) had normal RC tendons with good clinical outcome. Four (14%) patients had painful tendinosis without RC tear. A full‐thickness RC tear was found in 7 (25%) patients and a partial tear in 6 (21%). In one patient with a full‐thickness tear, and in two with partial tear, tendinosis was found in another of the RC tendons. The subacromial space was narrowed in 13 (46%) of the patients. A narrowing of the subacromial space correlated with re‐tear ( P<0.05). Conclusions: The RC may be evaluated with standard MRI sequences without fat saturation at long‐term follow‐up. A normal appearance of the RC is correlated with good clinical outcome, while re‐tear and tendinosis are associated with pain.
Biochemical and cytologic analysis of cystic contents in benign non‐parasitic symptomatic hepatic cysts before and after ethanol sclerotherapy
Authors: Larssen T. B. , Rørvik J. , Horn A. , Karwinski B. , Skadberg Ø. , Pedersen O. M. , Rosendahl K. 
Published: August 2004

Purpose: To examine the fluid of liver cysts by cytologic and biochemical analysis before and after ethanol sclerotherapy in order to explore the etiology of cystic fluid reproduction after sclerotherapy. Material and Methods: The contents of 11 cysts in 11 patients were examined on the day of sclerotherapy, and 2–8 (mean 4.5) days later, and analysed for cytologic and biochemical parameters. Results: Cytologic signs of acute or subacute inflammatory reaction were absent before and present in all cysts after sclerotherapy. Biochemical parameters reflecting the acute inflammatory reaction (CRP, orosomucoid and haptoglobine), changes in capillary permeability (protein, albumin), and the cystic epithelial function (bilirubin, alkaline phosphatase) were significantly elevated after sclerotherapy. Conclusion: The post‐sclerotherapy fluid production is probably due to an inflammatory reaction. This may explain the success of performing sclerotherapy in one single session.
Giant Intracranial Aneurysms of the Anterior Circulation
Authors: Lavyne Michael H. , Jonathan Kleefield , Davis Kenneth R. , Ojemann Robert G. , Crowell Robert M. 
Published: August 2004

Abstract
The computed tomography (CT) characteristics and clinical features of giant (globoid) aneurysms of the anterior circulation are reviewed. These lesions appear on the CT scan as smoothly encapsulated ovoid masses, within which a partially patent lumen is seen after the infusion of iodinated contrast material. With careful analysis of the CT scan it may be possible to differentiate giant internal carotid artery, anterior cerebral artery, and middle cerebral artery aneurysms from other parasellar and hemispheric lesions.
Visual Evoked Potentials in Hydrocephalus: Relationship to Head Size, Shunting, and Mental Development
Authors: Norman A. Guthkelch , Robert J. Sclabassi , Robert P. Hirsch , John K. Vries 
Published: August 2004

Abstract
Flash-evoked visual cortical potentials were measured in 54 infants and children with symptomatic hydrocephalus; 54 shunted, asymptomatic infants and children; and 57 controls. All patients were evaluated for head size, mental development, and history of infection of the nervous system. Hydrocephalic infants up to 60 weeks of conceptional age showed significant changes in the maturation curve of the latency to the main positive peak Psub2 (P100), particularly when their hydrocephalus was associated with an enlarged head or with infection. Older children of normal mental development presenting with acute hydrocephalus of recent onset had normal latencies to Psub2. Some persistent ventriculomegaly after shunting was also compatible with normal visual evoked potentials (VEPs). After shunting, the latency to Psub2 became normal in most of the patients who showed normal mental development, whereas retarded hydrocephalic children of all ages continued to have abnormal VEPs.
Intracranial Meningioma Unmasked by Elective General Anesthesia: Report of Three Cases
Authors: Henry A. Young , Howard Smith , Susan A. Gregory , John Gleave 
Published: August 2004

Abstract
Three cases of intracranial meningioma unmasked by elective general anesthesia are reported. In each case, the meningioma was either asymptomatic or so subtly symptomatic that no suspicion of intracranial tumor had been entertained preoperatively. Each patient presented with failure to wake up after routine general anesthesia for a nonneurosurgical procedure. The management of unexplained failure to wake up after uncomplicated general anesthesia is discussed. Early computed tomographic scanning and neurosurgical consultation are suggested in such situations.
Cavernous Hemangioma with Bone Formation in a Child: Case Report
Authors: Takeyoshi Shimoji , Noboru Murakami , Akira Shimizu , Kiyoshi Sato , Shozo Ishii 
Published: August 2004

Abstract
A 13-year-old girl suffering from seizures who was found to have hemangioma calcificans in the frontal lobe was surgically treated. The favorable postoperative course of our patient as well as reported cases suggest early excision of the lesion if it is located in an accessible area. Histological examination confirmed ossification with marrow in the lesion. The literature regarding ossification in the brain is discussed briefly.
Association of Intracranial Aneurysm and Arteriovenous Malformation in Childhood
Authors: John R. Østergaard 
Published: August 2004

Abstract
The simultaneous occurrence in the same patient of an intracranial saccular aneurysm and an arteriovenous malformation (AVM) is a well-known phenomenon. Usually the aneurysms are related anatomically to the arteries supplying the AVM, and it is generally accepted that the aneurysms are caused by hemodynamic stresses resulting from the presence of an AVM. Because patients with both an AVM and an aneurysm are older than those presenting with an AVM alone, a time factor seems essential in the development of the aneurysm accompanying an AVM. In this article, the case reports of two children are presented. They both had a symptom-producing AVM and an attendant saccular aneurysm. The malformations were anatomically closely related and the significance of hemodynamic stresses in the development of the aneurysms cannot be neglected. However, in these two cases, the time factor obviously cannot be of vital importance. Therefore, another factor, possibly in the form of a vascular collagen defect, may be suspected as essential in the formation of aneurysms during childhood. The character of this defect is briefly discussed.
Computer Simulation for the Stereotactic Placement of Interstitial Radionuclide Sources into Computed Tomography-defined Tumor Volumes
Authors: Patrick J. Kelly , Bruce A. Kall , Stephan Goerss 
Published: August 2004

Abstract
This report describes a method for the preoperative determination of radioactive interstitial source placement within computed tomography (CT)-defined tumor boundaries. The method utilizes CT data obtained under stereotactic conditions. Tumor boundaries are digitized from CT slices and are retained in a three-dimensional computer matrix. A solid tumor volume is created by an interpolation program and may be sliced orthogonal to any specific stereotactic surgical view line. The surgeon may simulate radioactive source placement within the slices and view the resultant isodose configuration against tumor contours on successive slices. Once the best source placement has been determined, the computer outputs the mechanical adjustments that will be necessary on a stereotactic frame located in the operating room for the stereotactic placement of each source and gives the length of each source. Sources are stereotactically implanted utilizing a double-catheter afterloading technique.