bluuebunny/crossref_metadata_2025 huggingface dataset:
First and second law performance variations of a coal gasification fuel-cell-based combined cogeneration plant with varying load
Authors: Ghosh S , De S
Published: November 2004

An advanced combined cogeneration plant based on a solid oxide fuel cell (SOFC) stack, fuelled by synthetic gas by coal gasification, upstream of a gas turbine and heat recovery steam generator (HRSG) to generate power as well as process steam downstream of it, has been thermodynamically modelled. While the plant supplies a base load power and process heat, provision of a fuel cell bypass mechanism for the synthetic gas stream offers the flexibility of matching the varying electrical power or the process heat load on the plant. The simulated energetic and exergetic performance of such a plant is presented in this paper and the optimum point of operation is reported. The exergy analysis shows the second law performance variation of significant components of the plant with varying loads.
Model-based control strategies in the dynamic interaction of air supply and fuel cell
Authors: Grujicic M , Chittajallu K M , Law E H , Pukrushpan J T
Published: November 2004

Model-based control strategies are utilized to analyse and optimize the transient behaviour of a polymer electrolyte membrane (PEM) fuel cell system consisting of air and fuel supply subsystems, a perfect air/fuel humidifier and a fuel cell stack at constant fuel cell temperature. The model is used to analyse the control of the fuel cell system with respect to maintaining a necessary level of oxygen partial pressure in the cathode during abrupt changes in the current demanded by the user. Maintaining the oxygen partial pressure in the cathode is necessary to prevent short circuit and membrane damage. The results obtained indicate that the oxygen level in the cathode can be successfully maintained through feedforward control of the air compressor motor voltage. However, the net power provided by the fuel cell system is compromised during the transients following abrupt changes in the stack current, suggesting a need for power management via the use of a secondary power source such as a battery.
RNA kink turns to the left and to the right: FIGURE 1.
Authors: STROBEL SCOTT A. , ADAMS PETER L. , STAHLEY MARY R. , WANG JIMIN
Published: November 2004

A helix-loop-helix within the group I intron has most of the canonical sequence elements of a kink turn (K-turn), yet it bends in the opposite direction. The reverse K-turn kinks toward the major rather than the minor grooves of the flanking helices. This suggests that there are two distinct subclasses of tertiary structures that a K-turn secondary structure can adopt. The final structure may be specified by external factors, such as protein binding or the tertiary structural context, rather than the intrinsic conformation of the RNA.
Activation of the protein kinase PKR by short double-stranded RNAs with single-stranded tails
Authors: ZHENG XIAOFENG , BEVILACQUA PHILIP C.
Published: November 2004

The human RNA-activated protein kinase PKR is an interferon-induced protein that is part of the innate immune response and inhibits viral replication. The action of PKR involves RNA-dependent autophosphorylation leading to inhibition of translation. PKR has an N-terminal dsRNA-binding domain that can interact non-sequence specifically with long (>33 bp) stretches of dsRNA leading to activation. In addition, certain viral and cellular RNAs containing non-Watson–Crick structures and multiple, shorter dsRNA sections can regulate PKR. In an effort to identify novel binders and possible activators of PKR, we carried out selections on a partially structured dsRNA library using truncated and full-length versions of PKR. A library with 1011 sequences was constructed and aptamers that bound to His6-tagged proteins were isolated. Characterization revealed a novel minimal RNA motif for activation of PKR with the following unified structural characteristics: a hairpin with a nonconserved imperfect 16-bp dsRNA stem flanked by 10–15-nt single-stranded tails, herein termed a “ss-dsRNA motif.” Boundary experiments revealed that the single-stranded tails flanking the dsRNA core provide the critical determinant for activation. The ss-dsRNA motif occurs in a variety of cellular and viral RNAs, suggesting possible novel functions for PKR in nature.
Auf dem Wege zu gebrauchstauglichen Eye-Tracking-Systemen (Towards Usable Eye-Tracking Systems)
Authors: Schimpfky Nicole
Published: November 2004

Eye-Tracking-Systeme könnten für die Untersuchung von Nutzungsproblemen, die Benutzer mit Anwendungssoftware haben, besser eingesetzt werden, wenn bestimmte technische und methodische Voraussetzungen erfüllt wären. In diesem Artikel werden methodische Anforderungen an die Nutzung solcher Systeme entwickelt. Mit Blick auf diese Anforderungen werden technische Defizite aufgedeckt. Die Integration methodischer und technischer Anforderungen für die Anwendung von Eye-Tracking-Systemen in Usability-Laboratorien wird angeregt.
Flexible phases, modulated structures and the transmission electron microscope
Authors: Withers Ray L. , Norén Lasse , Liu Yun
Published: November 2004

A review of the application of transmission electron microscopy to the study of interface, composite and displacively modulated structures is given. The distinctly different mechanisms underlying structural modulation in each case are emphasized as is the practical application of transmission electron microscopy to problems such as pseudo-symmetry and twinning, to indexation in (3 + d)-dimensional superspace and to overall superspace symmetry and structural characterization.
X-ray diffuse scattering as precursor of incommensurate Peierls transitions in one-dimensional organic charge transfer conductors
Authors: Pouget Jean-Paul
Published: November 2004

Quasi-one dimensional (1D) conductors of the TTF-TCNQ family of charge transfer salts exhibit a Peierls transition which stabilizes a periodic lattice distortion (PLD), accompanied by a charge density wave (CDW) modulation, with an incommensurate 2k
F (and sometimes 4k
F) wave vector related to the band filling of the 1D electronic subsystem. The Peierls instability is announced on an extended temperature range by 1D structural fluctuations giving rise to an X-ray diffuse scattering consisting of diffuse sheets in the reciprocal space. In this paper, we analyse quantitatively the thermal dependence of the correlation length of these 1D structural fluctuations, given by the inverse half-width of these diffuse sheets, and of the peak intensity of the diffuse scattering, using the correct treatment of the thermodynamics of the Peierls chain. From this analysis we are able to extract some microscopic parameters of the electron gas undergoing the Peierls instability, and, in particular, to quantify the importance of the electron-electron Coulomb repulsions. Finally, we examine the effect of the disorder on the Peierls instability and we show that defects modify the pretransitional fluctuations through the formation of Friedel oscillations whose development is controlled by the PLD-CDW response function of the Peierls chain.
The study of incommensurate structures as a probe to reveal atomic interactions in crystals
Authors: Chapuis Gervais , Arakcheeva Alla
Published: November 2004

The structure of aperiodic crystals which in cludes incommensurate, quasi- and composite crystals is usu ally described in spaces of higher dimension, the so called su perspace. The main advantage of the superspace formalism is that an aperiodic structure in three dimensions recovers its full periodicity in higher dimensions. The symmetry prop erties of aperiodic crystals are obviously more convenient to describe in superspace too. The origin of the incommensurate nature of structures can often be found in competing inter atomic interactions. From molecular dynamics simulation of a simple three dimensional model with close-packed layers and a single degree of freedom for each particle, it is pos sible to find the existence conditions of commensurate and incommensurate phases. Incommensurate phases can already be predicted on the basis of nearest and next nearest neigh bour particle interactions only. We illustrate this principle of interactions with two examples of structures, Na2CO3 and K3In(PO4)2. These examples shows clearly the importance of non-oxygen interactions i.e. next nearest interactions for the formation of incommensurate structures.
Many P-Element Insertions Affect Wing Shape in Drosophila melanogaster
Authors: Weber Kenneth , Johnson Nancy , Champlin David , Patty April
Published: November 2004

A screen of random, autosomal, homozygous-viable P-element insertions in D. melanogaster found small effects on wing shape in 11 of 50 lines. The effects were due to single insertions and remained stable and significant for over 5 years, in repeated, high-resolution measurements. All 11 insertions were within or near protein-coding transcription units, none of which were previously known to affect wing shape. Many sites in the genome can affect wing shape.
Referential process–reaction curve for batch operations
Authors: Marchetti J. L.
Published: November 2004

An extension of the well‐known process–reaction curve method to empirically determine reduced‐complexity models aimed to the design and tuning of feedback controllers for nonstationary batch processes is reported. The basic idea is to isolate the dynamics associated with the manipulated variable from the main time‐variable behavior that characterizes the operation, by taking the time evolution of a previous run as reference. One or more input‐perturbed evolutions can then be compared to the previous dynamic pattern yielding referential reaction curves. This modeling approach cancels out most of the nonstationary behavior, allows capturing the dominant manipulated‐variable dynamics, and the use of available tuning rules for integrating systems. The effectiveness of this procedure is illustrated by using a nonlinear model of a bioreactor that simulates the production of xanthan gum. © 2004 American Institute of Chemical Engineers AIChE J, 50: 3160–3168, 2004
The Crystal Structures of the Dicesium Dodecahalogeno‐closo‐Dodecaborates Cs2[B12X12] (X: Cl, Br, I) and Their Hydrates.
Authors: Tiritiris Ioannis , Schleid Thomas
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
High‐Pressure Synthesis of Metallic Perovskite Ruthenate CaCu3Ga2Ru2O12.
Authors: Byeon Song‐Ho , Lee Seoung‐Soo , Parise John B. , Woodward Patrick M. , Hur Nam Hwi
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Chemoenzymatic Synthesis of (S)‐ and (R)‐Propranolol and Sotalol Employing One‐Pot Lipase Resolution Protocol.
Authors: Kamal Ahmed , Sandbhor Mahendra , Shaik Ahmad Ali
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Palladium‐Catalyzed Asymmetric Allylic Alkylation Using Chiral Hydrazone Ligands with Ferrocene Skeleton.
Authors: Mino Takashi , Segawa Hiroshi , Yamashita Masakazu
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
First Example of Molecular Iodine Catalyzed Allylation and Alkynylation of Cyclic Allylic Acetates.
Authors: Yadav J. S. , Reddy B. V. S. , Rao K. Vishweshwar , Raj K. Sarita , Rao P. Purushothama , Prasad A. R. , Gunasekar D.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Highly Selective Reduction of Acyclic β‐Alkoxy Ketones to Protected syn‐1,3‐Diols.
Authors: Cullen Aaron J. , Sammakia Tarek
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Thiourea Inhibitors of Herpesviruses. Part 3. Inhibitors of Varicella Zoster Virus.
Authors: Di Grandi Martin J. , Curran Kevin J. , Feigelson Gregg , Prashad Amar , Ross Adma A. , Visalli Robert , Fairhurst Jeanette , Feld Boris , Bloom Jonathan D.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Conversion of 1‐Boc‐indoles to 1‐Boc‐oxindoles.
Authors: Vazquez Enrique , Payack Joseph F.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Novel Analogues of Sydnone: Synthesis, Characterization and Antibacterial Evaluation.
Authors: Moustafa Mohamed A. , Gineinah Magdy M. , Nasr Magda N. , Bayoumi Waleed A. H.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis and Structure—Activity Relationships of Novel IKK‐β Inhibitors. Part 2. Improvement of in vitro Activity.
Authors: Murata Toshiki , et al. et al.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Iridium‐Catalyzed Coupling of Simple Primary or Secondary Amines, Aldehydes and Trimethylsilylacetylene: Preparation of Propargylic Amines.
Authors: Sakaguchi Satoshi , Mizuta Tomoya , Furuwan Masuyuki , Kubo Takashi , Ishii Yasutaka
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
An Efficient Synthesis of the ACE Inhibitor [Phenyl‐3H] Lisinopril.
Authors: Egan Judith A. , Filer Crist N.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Alkali and Alkaline Earth Ion Recognition and Transport
Authors: Cowan J. A.
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Base Catalysis in the Synthesis of Fine Chemicals
Authors: Figueras Francois
Published: November 2004

For Abstract see ChemInform Abstract in Full Text.
Nano‐scaled Biomolecular Field‐Effect Transistors: Prototypes and Evaluations
Authors: Maruccio Giuseppe , Visconti Paolo , Biasco Adriana , Bramanti Alessandro , Della Torre Antonio , Pompa Pier Paolo , Frascerra Vanessa , Arima Valentina , D'Amone Eliana , Cingolani Roberto , Rinaldi Ross
Published: November 2004

As modern electronics rapidly approach the ultimate level of integration (typically thought to be at the nanoscale level), the fascinating world of biomolecules provides new opportunities and directions for further miniaturization. In this work we review our results in the field of biomolecular electronics, starting from the fabrication of nanojunctions up to the implementation of hybrid devices.
Atomic Force Microscopic and Electrochemical Investigations of an Electrostatically Fabricated Single‐Wall Carbon Nanotubes Modified Electrode
Authors: Qu Xiaohu , Peng Zhangquan , Wang Yuling , Dong Shaojun
Published: November 2004

Single‐wall carbon nanotubes (SWNTs) sub‐monolayer film has been prepared by simply electrostatically adsorbing nanotubes onto a 2‐aminoethanethiol self‐assembled monolayer (SAM) on a gold bead electrode. Tapping‐mode atomic force microscopy (TM‐AFM) is used to characterize the SWNT film, which exhibits that the orientation of SWNTs on the SAM is horizontal and the surface coverage is quite low. The SWNTs modified electrode shows nearly ideal electrochemical response to Fe(CN)$\rm{ {_{6}^{3-}}}$/Fe(CN)$\rm{ {_{6}^{4-}}}$ redox probe. The electrode with such a low SWNTs coverage, however, shows good electrocatalytic behavior to cytochrome c.
Numerical simulation of water quality response to nutrient loading and sediment resuspension in Mikawa Bay, central Japan: quantitative evaluation of the effects of nutrient‐reduction measures on algal blooms
Authors: Anggara Kasih G. A. , Kitada T.
Published: November 2004

Eutrophication is caused by large influxes of nutrient into closed or semi‐closed water bodies due to agricultural runoff, urban waste disposal, and resuspension from the sediment itself. The objective of this study is to examine how effectively various nutrient‐reduction measures can improve water quality in Mikawa Bay, central Japan. Both hydrodynamic and water quality variables were simulated using a model which includes a series of hydrodynamic equations and 13 mass conservation equations related to water quality, such as chlorophyll‐a, dissolved oxygen, etc. The calculated spatial distribution and temporal variations of the chlorophyll‐a, nutrient, dissolved oxygen, as well as temperature and salinity, showed generally good agreement with field observations. Analysis of various nutrient‐reduction measures suggested that nutrient reduction from sediment resuspension can more effectively reduce chlorophyll‐a compared with nutrient loading reduction through rivers from land areas. For suppression of alga growth in Mikawa Bay, control of inorganic nitrogen, especially that of NH4, was a key factor. That is why a decrease in nutrient resuspension from sediment was more effective for reducing chlorophyll‐a, since nitrogen resuspension occurred mostly in the form of NH4. Copyright © 2004 John Wiley & Sons, Ltd.
Application of a distributed hydrological model and weather radar observations for flood management in the upper Tone River of Japan
Authors: Yang Dawen , Koike Toshio , Tanizawa Hiroshi
Published: November 2004

Through utilizing weather radar measurements, the present research explores the possibility of applying a coupled distributed hydrological model with reservoir operations to flood forecasting and control in the Okutone basin, located in the upstream region of the Tone River. The Tone River basin often suffers from heavy rainfall events as a result of rainy season frontal activity, typhoons and cumulus cloud activity associated with the local circulation. The reservoirs located in the Okutone basin play an important role in flood regulation. The simulation of a flood event in August 2001 shows the potential applicability of the distributed hydrological model and weather radar measurements for real‐time flood control. Copyright © 2004 John Wiley & Sons, Ltd.
Nitrate behaviour in the groundwater of a headwater wetland, Chiba, Japan
Authors: Tang Changyuan , Azuma Kazuaki , Iwami Yoshifumi , Ohji Baku , Sakura Yasuo
Published: November 2004

A wetland is an important part of the headwater in the discharge area of a basin. It controls not only groundwater discharge such as seepage or springs, but also the migration of chemical matter from the basin. In order to make clear how and where natural attenuation processes happen in wetlands, a typical headwater in Chiba, Japan, was chosen for an investigation of the behaviour of nitrate in groundwater. From the viewpoint of hydro‐geomorphology, the wetland in the study site can be divided into three zones: the shallow water‐table zone, the seepage zone, and the spring zone along the downstream direction. There were six piezometer groups; each group contained four piezometers, individually set at depths of 1, 2, 3 and 4 m. Major ions and δ15N of groundwater from piezometers, wells and springs were analysed. It was found that nitrate in groundwater mainly came from the fertilizers used in the upstream recharge area of the study site. When the groundwater moved up across the wetland, nitrate concentration in the groundwater decreased rapidly in the shallow water‐table zone due to denitrification. Nitrate‐free water can be found at the seepage zone. However, the behaviour of nitrate in the spring water was different from that in the seepage zone, since both dilution and denitrification processes were involved in the decrease of nitrate concentration in groundwater. In particular, the dilution process mainly controlled the decline of nitrate at the location where the nitrate‐free groundwater flowing horizontally from the seepage zone mixed with the high‐nitrate groundwater flowing upward before emerging as a spring. It was also found that denitrification only occurs suddenly in a narrow zone or a thin layer of the order of a few metres. Copyright © 2004 John Wiley & Sons, Ltd.
Performance analysis of different meteorological data and resolutions using MaScOD hydrological model
Authors: Shrestha Roshan , Tachikawa Yasuto , Takara Kaoru
Published: November 2004

Distributed meteorological data collected from different sources are rarely identical within the same domain of space and time. Discrepancies of these data in magnitude, pattern, and resolution play an important role in hydrological simulation. Using four different sets of distributed meteorological data (from the HUBEX‐Intense Observation Period and GAME experimental products at different resolutions), hydrological simulations are conducted through a distributed hydrological model called MaScOD (macro‐scale OHyMoS assisted distributed) hydrological model. The model's performance is measured using 12 different indexes. Based on these indexes, a relative normalized score is calculated to evaluate the overall performance of the result from each data set. Three sub‐basins of the Huaihe River basin in China, taking the cases at Bengbu (132 350 km2), Wangjiaba (29 844 km2) and Suiping (2093 km2), are used for numerical experiments. This study shows the competence of coarse‐resolution meteorological data, the GAME reanalysis 1·25° data, to apply in hydrological simulations of large catchments. However, that data failed to simulate the hydrograph in smaller catchments. The results are significantly improved by including spatial variability at finer resolution in that data. Copyright © 2004 John Wiley & Sons, Ltd.
Electrophysiological studies of myoclonus
Authors: Shibasaki Hiroshi , Hallett Mark
Published: November 2004

As myoclonus is often associated with abnormally increased excitability of cortical structures, electrophysiological studies provide useful information for its diagnosis and classification, and about its generator mechanisms. The electroencephalogram–electromyogram polygraph reveals the most important information about the myoclonus of interest. Jerk‐locked back‐averaging and evoked potential studies combined with recording of the long‐latency, long‐loop reflexes are useful to investigate the pathophysiology of myoclonus further, especially that of cortical myoclonus. Recent advances in magnetoencephalography and transcranial magnetic stimulation have contributed significantly to the understanding of some of the cortical mechanisms underlying myoclonus. Elucidation of physiological mechanisms underlying myoclonus in individual patients is important for selecting the most appropriate treatment. Muscle Nerve, 2005
A case study of os cuneiforme mediale bipartum from Sigtuna, Sweden
Authors: Kjellström A.
Published: November 2004

An adult male from an early Medieval mass grave in Sigtuna displayed bilateral os cuneiforme mediale bipartum. This is an unusual congenital anomaly and this study is the first published example found in an archaeological skeletal assemblage in Sweden. Another adult male in the same grave shows horizontal grooves of both medial cuneiform bones. This paper discusses a possible hereditary tendency of the anomalies. Copyright © 2004 John Wiley & Sons, Ltd.
Early complications in children with acute lymphoblastic leukemia presenting with hyperleukocytosis
Authors: Lowe Eric J. , Pui Ching‐Hon , Hancock Michael L. , Geiger Terrence L. , Khan Raja B. , Sandlund John T.
Published: November 2004

Background

The optimal management of childhood acute lymphoblastic leukemia (ALL) with hyperleukocytosis is unclear, largely because the risk of leukostasis‐related complications is poorly characterized.

Procedure

We reviewed the presenting characteristics, initial management, and frequency and type of complications in all children seen at St. Jude Children's Research Hospital with previously untreated ALL and an initial leukocyte count >200 × 109/L.

Results

A total of 178 children, representing 8% of all children with ALL, had an initial leukocyte count >200 × 109/L; 67 patients had a leukocyte count >400 × 109/L. Sixteen patients (9%) had neurological complications with 12 of these patients experiencing symptoms at presentation. Four patients (2%), all with initial leukocyte counts >400 × 109/L, suffered a CNS hemorrhage. Pulmonary leukostasis occurred in 11 patients (6%). The degree of hyperleukocytosis was significantly predictive of neurological (P = 0.006) and respiratory (P = 0.014) complications. The majority of complications occurred at presentation. Cytoreduction (94 patients) decreased the leukocyte count but delayed initiation of chemotherapy (P = 0.013).

Conclusions

Serious leukostasis‐related complications are relatively uncommon in childhood ALL and most occur at presentation. Their incidence increases in proportion to the leukocyte count. A large subset of cases can be managed successfully without cytoreduction. Cytoreduction may be considered for patients with leukocyte counts >400 × 109/L or patients who have complications at presentation. Pediatr Blood Cancer 2005; 45:10–15. © 2004 Wiley‐Liss, Inc.
Studies on physico‐mechanical properties and thermal characteristics of polypropylene/layered silicate nanocomposites
Authors: Parija S. , Nayak S. K. , Verma S. K. , Tripathy S. S.
Published: November 2004

Polypropylene/layered silicate nanocomposites were prepared from base polymer (10 MFI) and octadecylamine modified montmorillonite (1.30P nanomer), melt compounded with and without compatibilizer, i.e., maleic anhydride grafted polypropylene (Epolene‐G3015). Physico‐mechanical properties of the virgin PP and nanocomposites with different nanomer percentages and compatibilizer loadings were studied and compared. Thermal characteristics of nanocomposites were also compared with those of the virgin polymer. TEM analysis of the nanocomposites was carried out to study the dispersion of nanomer in the resulting hybrids. The nanocomposites showed improved mechanical properties over those of the virgin polymer with a marginal increase in specific gravity. Addition of compatibilizer further enhanced the mechanical properties of nanocomposites because of the compatibilization of the clay and host polymer interface. The uncompatibilized nanocomposites showed an increase in thermal stability and a higher melting point. However, the compatibilized nanocomposites showed delayed crystallization due to the presence of an oligomeric fraction of the added Epolene. Polym. Compos. 25:646–652, 2004. © 2004 Society of Plastics Engineers.
Aspirin use for prevention of vascular complications in diabetes mellitus
Authors: Baldeweg SE , Hurel SJ
Published: November 2004

Cardiovascular events represent the major cause of death in diabetes. In 2004 the American Diabetes Association has re‐issued recommendation that diabetic adults with an additional risk factor for cardiovascular disease should be treated with aspirin. Similar guidelines exist from the Joint British Societies. Previous studies have demonstrated a low prescribing rate of aspirin in those patients.

We aimed to assess the use of aspirin in our diabetes outpatient department and to identify methods with which to increase its use.

The notes of 100 patients attending the diabetes clinic were randomly selected on three occasions (six, 12 and 18 months). Information on risk factors and aspirin use was collected. Following the first review we raised awareness on this issue.

Our data demonstrate that physicians were aware of the need for secondary cardiovascular prevention in patients with diabetes. However, prescribing for primary prevention was low. After raising awareness through further education, aspirin prescribing increased. This improvement was sustained at 18 months.

Simple education measures within a local team as part of an audit cycle, have led to a significant improvement in numbers of aspirin prescriptions. This should, especially in view of the recently published meta‐analysis on trials of antiplatelet therapy, translate into a long‐term improvement in vascular outcome in this patient group. Copyright © 2004 John Wiley & Sons, Ltd.
Diagnostic delays in diabetic Charcot arthropathy
Authors: Gill GV , Hayat H , Majid S
Published: November 2004

Charcot Arthropathy in the diabetic foot can result in permanent deformity if not diagnosed and treated promptly. We report four diabetic patients in whom the diagnosis of neuropathy was delayed by up to six months, with misdiagnoses including deep venous thrombosis, cellulitis, gout and ankle sprain. In all cases, the clinical scenario and appearances were typical of charcot arthropathy. Fortunately, only minor deformity occurred in one patient. A higher index of suspicion for the possibility of charcot foot is needed. Copyright © 2004 John Wiley & Sons, Ltd.
Synthesis of core–shell microspheres with active hydroxyl groups by two‐stage precipitation polymerization
Authors: Bai Feng , Yang Xinlin , Zhao Yuzeng , Huang Wenqiang
Published: November 2004

Monodisperse micrometer microspheres having active hydroxyl groups with a dense core and a lightly crosslinked functional shell were prepared by two‐stage precipitation polymerization in the absence of any stabilizer. Commercial divinylbenzene (DVB), containing 80 % of DVB was polymerized by precipitation in acetonitrile without any stabilizer as the first stage polymerization and used as the core. When the conversion of DVB was about 60 % in the first stage, hydroxyethyl methacrylate (HEMA) and azobisisobutyronitrile (AIBN) were introduced into the reaction system and copolymerized with unreacted DVB on the core surface to form a lightly crosslinked functional shell with hydroxyl groups formed on the surface during the second stage precipitation polymerization. Both the crosslinking degree and the thickness of the shell layer depend on HEMA loading. The kinetic study demonstrated that the conversion of HEMA increased slightly with increasing HEMA loading. Higher HEMA loading and AIBN concentration increased the reaction rate significantly and formed more soluble oligomers, which resulted in secondary initiation with high HEMA loading. The resulting core–shell polymer particles were characterized with scanning electron microscopy (SEM), and FTIR. Copyright © 2004 Society of Chemical Industry
Sclerosing Rhabdomyosarcomas in Children and Adolescents: A Clinicopathologic Review of 13 Cases from the Intergroup Rhabdomyosarcoma Study Group and Children's Oncology Group
Authors: Chiles Melissa C. , Parham David M. , Qualman Stephen J. , Teot Lisa A. , Bridge Julia A. , Ullrich Fred , Barr Frederic G. , Meyer William H. ,   For the Soft Tissue Sarcoma Committee of the Children's Oncology Group
Published: November 2004

In recent reports, investigators have described a variant of adult sclerosing rhabdomyosarcoma (RMS) that is characterized by a hyalinizing, matrix-rich stroma. To determine whether this variant occurs in children, we investigated this phenomenon in a recent series of 1207 pediatric patients who had RMS accessioned by the Intergroup Rhabdomyosarcoma Study Group, now part of Children's Oncology Group. Thirteen patients had features of sclerosing RMS; 9 had been diagnosed with alveolar RMS (ARMS), 3 with embryonal RMS (ERMS), and 1 with a spindle cell RMS. Primary sites included head and neck (6 patients), extremities (5 patients), scrotum (1 patient), and retroperitoneum (1 patient). Patients' ages ranged from 0.3 to 16 years. All tumors showed positivity for myogenin, MyoD, and desmin, but only 2 patients demonstrated the strong myogenin staining typically seen in ARMS. Three patients diagnosed with ARMS demonstrated embryonal-appearing foci, and 3 of 4 patients who had nonalveolar tumors had ARMS-like foci. Standard reverse transcriptase–polymerase chain reaction performed on RNA isolated from frozen sections showed 1 ARMS with a positivity for PAX3-FKHR with four patients classified as having ARMS and 1 as having spindle cell RMS were negative for both ARMS fusion transcripts (PAX3- and PAX7-FKHR). Cytogenetic testing in 2 patients who had ARMS-like foci demonstrated mild hyperdiploidy in both patients and a near-tetraploid clone in 1 patient. Sclerosing RMS may arise in children, have mixed ERMS-ARMS histology, originate from the head and neck, and lack strong myogenin staining.
Extrapleural Benign Solitary Fibrous Tumor in the Shoulder of a 9-Year-Old Girl: Case Report and Review of the Literature
Authors: Rakheja Dinesh , Wilson Kathleen S. , Meehan John J. , Schultz Roger A. , Maale Gerhard E. , immons Charles F. T
Published: November 2004

We report a case of a benign solitary fibrous tumor that occurred in the right shoulder of a 9-year-old girl. This case is remarkable due to the unusual location of its occurrence and the young age of the patient. In addition, cytogenetic analysis revealed a karyotype unreported in this neoplasm: 46,XX,der(4)t(4;9)(q31.1;q34), del(9)(p22p24),der(9)t(4;9)(q31.1;q34)ins(9;?)(q34;?) (17 cells)/46,XX (3 cells).
“Proximal-type” and Classic Epithelioid Sarcomas Represent a Clinicopathologic Continuum: Case Report
Authors: Rakheja Dinesh , Wilson Kathleen S. , Meehan John , Schultz Roger A. , Gomez Ana M.
Published: November 2004

We report a case of an epithelioid sarcoma that occurred in the right hand of a 14-year-old boy and had the “proximal-type” morphology and a complex, near-tetraploid karyotype. The tumor metastasized to the lungs, where the morphology was typical for the classic epithelioid sarcoma. Based on the morphologic and cytogenetic findings in this case, we suggest that the proximal-type and the classic epithelioid sarcomas are not distinct entities but represent a continuum.
Subclassification of Anencephalic Human Fetuses According to Morphology of the Posterior Cranial Fossa
Authors: Lomholt Jens Fog , Fischer-Hansen Birgit , Keeling Jean W. , Reintoft Ingermarie , Kjær Inger
Published: November 2004

Anencephaly is a designation for congenital absence of the cranial vault with cerebral hemispheres completely missing or decreased to small masses attached to the base of the skull. The etiology is unknown. Whether the bony tissue or soft brain tissue is a primary factor is also unknown. The present study has focused on the posterior cranial fossa in anencephaly. The goal is to determine whether differences in the posterior cranial fossa could provide a basis for subclassification of anencephalic fetal skeletons. Twenty-three human anencephalic fetuses, at gestational ages 13 to 22 weeks, were studied. Radiologic and cephalometric analyses, including measurements of bone sizes and different angles, were performed. Permission for autopsy of the central nervous system was not available. For comparison of anencephalic findings with normal conditions, standards from a recent publication were used. Foot length served as a parameter for age comparison. The study showed 2 morphologic types of the posterior cranial fossa. One type had a fossa cranial morphology close to normal morphology, whereas the other had a malformed and much smaller posterior cranial fossa. The latter condition was presumed to be due to a primary error in chondral and cranial development. The current skeletal subgrouping might be essential for clinicians' or pathologists' future assessment of the autopsy results. The skeletal subgrouping should, if possible, be associated with karyotyping and analysis of the central nervous system. The goal is to distinguish between congenital conditions resulting in anencephaly and acquired conditions resulting in anencephaly.
Misoprostol use in developing countries: results from a multicountry study
Authors: Sherris J. , Bingham A. , Burns M.A. , Girvin S. , Westley E. , Gomez P.I.
Published: November 2004

Objective: To identify information and service delivery needs for obstetric/gynecologic uses of misoprostol in developing countries. Methods: The study included a survey of reproductive health providers in 23 countries and a qualitative study of misoprostol use in four developing countries. Researchers used purposive sampling methods for the survey and qualitative study and conducted a descriptive statistical analysis of survey data and computer‐assisted text‐based content analysis of qualitative data. Results: In some developing countries, women frequently access misoprostol through pharmacies and self‐medicate to induce early abortion. Some clinicians expressed concern about this use of misoprostol, but many stated that its availability had reduced serious complications resulting from unsafe abortions. Conclusion: Although misoprostol is routinely used for a range of off‐label obstetric/gynecologic indications, evidence‐based, up‐to‐date information about safety, effectiveness, and appropriate regimens is not widely available. This information is requested by providers, including pharmacists. Women need information and guidance about its use.
Pain Assessment and Intervention for Term Newborns
Authors: Clifford Patricia A. , Stringer Marilyn , Christensen Holly , Mountain Deborah
Published: November 2004

A baseline assessment of pain should occur as part of a newborn's health assessment within the first few hours of life. Validation and assessment of pain in the term newborn is important for providing care because newborns may experience pain from a multitude of procedures, ranging from heel sticks to circumcisions. Current assessment tools evaluate both behavioral and physiologic parameters. In addition, providing individualized care requires a knowledge base of the interventions available to reduce or eliminate pain, such as breastfeeding, non‐nutritive suck, skin‐to‐skin contact, and sucrose pacifiers. This article describes three newborn pain assessment tools, the use of valid assessment tools, and evidence‐based interventions that are recommended to effectively manage newborn pain.
Pain at Midlife
Authors: Rousseau Mary Ellen , Gottlieb Sarabeth F.
Published: November 2004

Although menopause is a normal developmental milestone through which all women pass, the transition has been long associated with chronic pain conditions that may be more accurately viewed as secondary to aging. Clinicians need to understand management of pain problems women may experience. This article examines pain syndromes including headache, back pain, osteoarthritis, pelvic pain, vulvo‐vaginal pain, and burning mouth syndrome.
Obstetric Anesthesia: Changes and Choices
Authors: McCool William F. , Packman Jana , Zwerling Arthur
Published: November 2004

This article is a review of analgesics and anesthetics offered to laboring women, including intravenous drugs, epidural and spinal agents, and inhalational anesthetics. An overview of the uses, risks, and benefits is provided for each anesthetic alternative. To provide the most effective care to women in labor, clinicians have a responsibility to have current knowledge of the best evidence for safety and efficacy of these pharmacologic agents and techniques and be able to effectively communicate this information to clients.
Explaining risk factors for drug-resistant tuberculosis in England and Wales: contribution of primary and secondary drug resistance
Authors: CONATY S. J. , HAYWARD A. C. , STORY A. , GLYNN J. R. , DROBNIEWSKI F. A. , WATSON J. M.
Published: November 2004

Drug-resistant tuberculosis can be transmitted (primary) or develop during the course of treatment (secondary). We investigated risk factors for each type of resistance. We compared all patients in England and Wales with isoniazid- and multidrug-resistant tuberculosis in two time-periods (1993–1994 and 1998–2000) with patients with fully sensitive tuberculosis, examining separately patients without and with previous tuberculosis (a proxy for primary and secondary drug-resistant tuberculosis). Patients with previous tuberculosis smear positivity and arrival in the United Kingdom <5 years were strongly associated with multidrug resistance and isoniazid resistance. In patients with no previous tuberculosis HIV infection, residence in London and foreign birth were risk factors for multidrug resistance, and non-white ethnicity, residence in London and HIV infection for isoniazid resistance. Risk factors for each type of resistance differ. Elevated risks associated with London residence, HIV positivity, and ethnicity were mainly seen in those without previous tuberculosis (presumed transmission).
Definition and estimation of an actual reproduction number describing past infectious disease transmission: application to HIV epidemics among homosexual men in Denmark, Norway and Sweden
Authors: AMUNDSEN E. J. , STIGUM H. , RØTTINGEN J.-A. , AALEN O. O.
Published: November 2004

Prevalence and incidence measures are the common way to describe epidemics. The reproduction number supplies information on the potential for growth or decline of an epidemic. We define an actual reproduction number for infectious disease transmission that has taken place. An estimator is suggested, based on the number of new infections observed in a given time-interval, the number of those infected at the start of the interval, and the length of the infectious period. That estimator is applied to HIV among men having sex with other men over the period, 1977–1995, in Scandinavia. The actual reproduction number was estimated with acceptable certainty from the period, 1981–1982, yielding a value of 15 secondary cases. A value of less than one secondary case was assessed for the period, 1988–1995, in Denmark and Sweden. The actual reproduction number gives us some additional understanding of the dynamics of epidemics, compared with prevalence and incidence curves.
Visual Perception and Perceptual Processing in Real and Virtual Environments
Authors: Groner Rudolf , Koga Kazuo , Tsuji Keiichiro
Published: November 2004

We present a brief outline of the development of research in visual perception with the advent of new technologies up to New Media and virtual environments. There is a mutual inspiration and benefiting between fundamental and applied research and technological progress which should be utilized by the disciplines involved. Next, an overview of a conference, held in Nara (Japan) September 2001, is given of which different selections of articles are presented in the current special issues of the Swiss Journal of Psychology and of Japanese Psychological Research.
Visual Latency Difference Determined by Two ‘‘Rotating’’ Pulfrich Techniques
Authors: Nakamizo Sachio , Nickalls Richard William Dye , Nawae Hiroki
Published: November 2004

We tested the validity of Nickalls’ formula for determining visual latency difference by using two rotating Pulfrich techniques: (A) varying viewing distance while keeping target angular velocity constant (33 rev/min) and (B) varying the target angular velocity while keeping the viewing distance constant (180 cm). The formula predicts that the latency differences estimated by the two techniques are equal with a given neutral density filter. Observers were asked to judge whether or not the rotating target (clockwise) appeared to move back-and-forth from side-to-side with a neutral density filter (OD = 0.7, 1.0, 1.3) in front of the right eye. The results with ten observers showed that the mean visual latency differences associated with each technique for a given filter were not significantly different. These results further validate the Nickalls’ formula and, therefore, support the visual-latency hypothesis to account for the Pulfrich phenomenon.
3‐D global MHD model prediction for the first close flyby of Titan by Cassini
Authors: Ma Ying‐Juan , Nagy Andrew F. , Cravens Thomas E. , Sokolov Igor V. , Clark John , Hansen Kenneth C.
Published: November 2004

The global features of the interaction between Saturn's magnetospheric plasma flow and Titan's atmosphere/ionosphere are simulated by using a 3‐D, multi‐species, high spatial resolution, global MHD model. Our model uses a spherical grid structure leading to very good (∼36 km) altitude resolution in the ionospheric region of Titan. The model also provides good resolution and meaningful results in the upstream and wake regions. Titan's atmosphere and ionosphere are approximated by 10 neutral and 7 ion species. Calculations, which make predictions for the anticipated results to be obtained by the Cassini spacecraft during its first close flyby (TA) of Titan, are presented.
Simulating changes in regional air pollution over the eastern United States due to changes in global and regional climate and emissions
Authors: Hogrefe C. , Lynn B. , Civerolo K. , Ku J.‐Y. , Rosenthal J. , Rosenzweig C. , Goldberg R. , Gaffin S. , Knowlton K. , Kinney P. L.
Published: November 2004

To simulate ozone (O3) air quality in future decades over the eastern United States, a modeling system consisting of the NASA Goddard Institute for Space Studies Atmosphere‐Ocean Global Climate Model, the Pennsylvania State University/National Center for Atmospheric Research mesoscale regional climate model (MM5), and the Community Multiscale Air Quality model has been applied. Estimates of future emissions of greenhouse gases and ozone precursors are based on the A2 scenario developed by the Intergovernmental Panel on Climate Change (IPCC), one of the scenarios with the highest growth of CO2 among all IPCC scenarios. Simulation results for five summers in the 2020s, 2050s, and 2080s indicate that summertime average daily maximum 8‐hour O3 concentrations increase by 2.7, 4.2, and 5.0 ppb, respectively, as a result of regional climate change alone with respect to five summers in the 1990s. Through additional sensitivity simulations for the five summers in the 2050s the relative impact of changes in regional climate, anthropogenic emissions within the modeling domain, and changed boundary conditions approximating possible changes of global atmospheric composition was investigated. Changed boundary conditions are found to be the largest contributor to changes in predicted summertime average daily maximum 8‐hour O3 concentrations (5.0 ppb), followed by the effects of regional climate change (4.2 ppb) and the effects of increased anthropogenic emissions (1.3 ppb). However, when changes in the fourth highest summertime 8‐hour O3 concentration are considered, changes in regional climate are the most important contributor to simulated concentration changes (7.6 ppb), followed by the effect of increased anthropogenic emissions (3.9 ppb) and increased boundary conditions (2.8 ppb). Thus, while previous studies have pointed out the potentially important contribution of growing global emissions and intercontinental transport to O3 air quality in the United States for future decades, the results presented here imply that it may be equally important to consider the effects of a changing climate when planning for the future attainment of regional‐scale air quality standards such as the U.S. national ambient air quality standard that is based on the fourth highest annual daily maximum 8‐hour O3 concentration.
Regulation of cardiac Na–Ca exchange activity by selective tyrosine kinase inhibition
Authors: Harvey Robert D
Published: November 2004

British Journal of Pharmacology (2004) 143, 929–930. doi:10.1038/sj.bjp.0706009
Numerical simulation of polymer nanocomposites using self-consistent mean-field model
Authors: Kim K. , Utracki L. A. , Kamal M. R.
Published: November 2004

Clay-containing polymeric nanocomposites (PNC) are mixtures of dispersed clay platelets in a polymeric matrix. These materials show enhancement of physical properties, such as modulus, strength, and dimensional stability, as well as a reduction of gas permeability and flammability. The performance is related to the degree of clay dispersion (i.e., intercalation or exfoliation) and the bonding between the clay and the matrix. The main goal of this work has been to map the degree of dispersion as a function of independent variables (viz., magnitude of the interaction parameters, molecular weights, composition, etc.). In this paper, we present the results of the numerical analysis of the equilibrium thermodynamic miscibility using one- and two-dimensional (1D and 2D) models based on the self-consistent mean-field theory. In the limit, the 2D model reproduced the 1D model published results. The adopted 2D model considers the presence of four PNC components: solid clay platelets, low molecular weight intercalant, polymeric matrix, and end-functionalized compatibilizer. The simulations, with realistic values of the binary interaction parameters, were analyzed for potential exfoliation of PNC with a polyolefin as the matrix. The simulation results show that intercalation and exfoliation is expected within limited ranges of the independent variables. The presence of a bare clay surface (e.g., generated by thermal decomposition of intercalant or extraction by molten polymer) has a strong negative effect on the dispersion process. The simulation successfully identified the most influential factors, e.g., optimum ranges of the compatibilizer and the intercalant concentration.