bluuebunny/crossref_metadata_2025 huggingface dataset:
About smoothness of solutions of the heat equations in closed, smooth space‐time domains
Authors: Dong Hongjie
Published: March 2005

We consider the probabilistic solutions of the heat equation u = u + f in D, where D is a bounded domain in ℝ2 = {(x1, x2)} of class C2k. We give sufficient conditions for u to have kth‐order continuous derivatives with respect to (x1, x2) in D̄ for integers k ≥ 2. The equation is supplemented with C2k boundary data, and we assume that f ϵ C2(k−1). We also prove that our conditions are sharp by examples in the border cases. © 2005 Wiley Periodicals, Inc.
A quantitative compactness estimate for scalar conservation laws
Authors: de Lellis Camillo , Golse François
Published: March 2005

In the case of a scalar conservation law with convex flux in space dimension one, P. D. Lax proved [Comm. Pure and Appl. Math. 7 (1954)] that the semigroup defining the entropy solution is compact in L for each positive time. The present note gives an estimate of the ϵ‐entropy in L of the set of entropy solutions at time t > 0 whose initial data run through a bounded set in L1. © 2005 Wiley Periodicals, Inc.
Sternberg theorems for random dynamical systems
Authors: Li Weigu , Lu Kening
Published: March 2005

In this paper, we prove the smooth conjugacy theorems of Sternberg type for random dynamical systems based on their Lyapunov exponents. We also present a stable and unstable manifold theorem with tempered estimates that are used to construct conjugacy. © 2005 Wiley Periodicals, Inc.
Crystallographic and Electrochemical Characteristics of La0.7Mg0.3Ni5.0−x(Al0.5Mo0.5)x Hydrogen‐Storage Alloys
Authors: Zhang Xin Bo , Sun Dan Zi , Yin Wen Ya , Chai Yu Jun , Zhao Min Shou
Published: March 2005

The structure, hydrogen‐storage property and electrochemical characteristics of La0.7Mg0.3Ni5.0−x(Al0.5Mo0.5)x (x=0–0.8) hydrogen‐storage alloys have been studied systematically. X‐ray diffraction Rietveld analysis shows that all the alloys consist of an La(La,Mg)2Ni9 phase and an LaNi5 phase. The pressure–composition isotherms indicate that the hydrogen‐storage capacity first increases and then decreases with increasing x, and the equilibrium pressure decreases with increasing x. Electrochemical measurements show that the maximum discharge capacity and the exchange‐current density of the alloy electrodes increase as x increases from 0 to 0.6 and then decrease when x increases further from 0.6 to 0.8. Moreover, the low‐temperature dischargeability of the alloy electrodes increases monotonically with increasing x in the alloys.
Wetting of Surfactant Solutions by Alkanes
Authors: Wilkinson Katherine M. , Bain Colin D. , Matsubara Hiroki , Aratono Makoto
Published: March 2005

Ellipsometry, surface tensiometry, and contact‐angle measurement have been used to study the transition between partial wetting and pseudo‐partial wetting of surfactant solutions by alkanes. In the partial wetting regime, the air–water surface tension is the same with and without alkane. In the pseudo‐partial wetting regime, the air–water surface tension is lowered by the presence of alkane, showing that oil is solubilised into the surfactant monolayer. A discontinuous change in the coefficient of ellipticity with increasing surfactant concentration provides unequivocal evidence for the first‐order nature of the wetting transitions. Ellipsometry has been used to explore the generality of wetting transitions of alkanes (dodecane, hexadecane, and squalane) on surfactant solutions [dodecyltrimethylammonium bromide, tetredecyltrimethylammonium bromide, dibucaine hydrochloride, and Aerosol OT (AOT)]. Of the systems studied, only hexadecane on AOT solutions did not show a wetting transition. Excess alkane remains as a lens on the surface of the surfactant solutions at all concentrations, but the contact angle is a minimum at the wetting transition. A semiquantitative model for the variation of the contact angle with surfactant concentration is provided.
Cover Picture: Wetting of Surfactant Solutions by Alkanes (ChemPhysChem 3/2005)
Authors: Wilkinson Katherine M. , Bain Colin D. , Matsubara Hiroki , Aratono Makoto
Published: March 2005

The cover picture shows a cut‐away section of an oil droplet on a surfactant solution, in which a lens of oil is in equilibrium with a mixed monolayer of surfactant and oil. The background is a Brewster angle micrograph of a drop of hexadecane on a 1.2 mM solution of dodecyltrimethylammonium bromide (DTAB), just above the wetting transition. In their article on page 547, Wilkinson et al. show that first‐order wetting transitions in alkanes on surfactant solutions are a general, but not universal, phenomenon.
Performance of numerical methods on the non‐unique solution to the Riemann problem for the shallow water equations
Authors: Andrianov Nikolai
Published: March 2005

For certain initial conditions, the exact solution to the Riemann problem for the shallow water equations is not unique. We test the performance of several numerical methods on such initial data and establish that the numerical solution can pick out different exact solutions. Moreover, the numerical solution does not necessarily converge towards the picked‐out exact solution. Copyright © 2005 John Wiley & Sons, Ltd.
Very large inverse problems in atmosphere and ocean modelling
Authors: Johnson C. , Nichols N. K. , Hoskins B. J.
Published: March 2005

For the very large nonlinear dynamical systems that arise in a wide range of physical, biological and environmental problems, the data needed to initialize a numerical forecasting model are seldom available. To generate accurate estimates of the expected states of the system, both current and future, the technique of ‘data assimilation’ is used to combine the numerical model predictions with observations of the system measured over time. Assimilation of data is an inverse problem that for very large‐scale systems is generally ill‐posed. In four‐dimensional variational assimilation schemes, the dynamical model equations provide constraints that act to spread information into data sparse regions, enabling the state of the system to be reconstructed accurately. The mechanism for this is not well understood. Singular value decomposition techniques are applied here to the observability matrix of the system in order to analyse the critical features in this process. Simplified models are used to demonstrate how information is propagated from observed regions into unobserved areas. The impact of the size of the observational noise and the temporal position of the observations is examined. The best signal‐to‐noise ratio needed to extract the most information from the observations is estimated using Tikhonov regularization theory. Copyright © 2005 John Wiley & Sons, Ltd.
Extraosseous IL‐6 transgenic mouse plasmacytoma sometimes lacks Myc‐activating chromosomal translocation
Authors: McNeil Nicole , Kim Joong Su , Ried Thomas , Janz Siegfried
Published: March 2005

The cellular oncogene MYC and plasma cell growth, differentiation, and survival factor IL‐6 play critical roles in the natural history of human plasma cell neoplasms such as multiple myeloma (MM). Myc and IL‐6 also are at the center of neoplastic plasma cell transformation in BALB/c mice that carry a human IL‐6 transgene and, therefore, predictably develop plasmacytomas (PCTs). We showed previously that, much like advanced MM or human myeloma cell lines (HMCLs), in which MYC is frequently deregulated in cis because of complex cytogenetic aberrations juxtaposing MYC to immunoglobulin enhancers, IL‐6 transgenic PCTs commonly deregulate Myc in cis by chromosomal translocation, predominantly T(12;15)(Igh–Myc). In this article, we show that, analogous to primary MM in which MYC is mostly deregulated in trans by signaling pathways converging at the MYC promoter, IL‐6 transgenic PCTs sometimes develop in the absence of Myc translocations, thus activating Myc in trans. We present cytogenetic and molecular evidence on two IL‐6 transgenic PCTs that contained overexpressed Myc protein but lacked T(12;15)(Igh–Myc) and two related Myc–‐deregulating translocations that juxtapose Myc to immunoglobulin light‐chain instead of heavy‐chain enhancers: T(6;15)(Igκ–Pvt1) and T(15;16)(Pvt1–Igλ). We conclude that Myc translocations are not strictly required for IL‐6‐driven PCT development in mice. IL‐6 transgenic PCTs may provide a valuable model system for elucidating both trans and cis mechanisms of Myc deregulation of great relevance for MYC deregulation in human MM. © 2005 Wiley‐Liss, Inc.
Simulation of floods caused by overloaded sewer systems: extensions of shallow‐water equations
Authors: Hilden Michael
Published: March 2005

The outflow of water from a manhole onto a street is a typical flow problem within the simulation of floods in urban areas that are caused by overloaded sewer systems in the event of heavy rains. The reliable assessment of the flood risk for the connected houses requires accurate simulations of the water flow processes in the sewer system and in the street.

The Navier–Stokes equations (NSEs) describe the free surface flow of the fluid water accurately, but since their numerical solution requires high CPU times and much memory, their application is not practical. However, their solutions for selected flow problems are applied as reference states to assess the results of other model approaches.

The classical shallow‐water equations (SWEs) require only fractions (factor 1/100) of the NSEs' computational effort. They assume hydrostatic pressure distribution, depth‐averaged horizontal velocities and neglect vertical velocities. These shallow‐water assumptions are not fulfilled for the outflow of water from a manhole onto the street. Accordingly, calculations show differences between NSEs and SWEs solutions.

The SWEs are extended in order to assess the flood risks in urban areas reliably within applicable computational efforts. Separating vortex regions from the main flow and approximating vertical velocities to involve their contributions into a pressure correction yield suitable results. Copyright © 2005 John Wiley & Sons, Ltd.
Isolation of a free radical‐scavenging antioxidant from water spinach (Ipomoea aquatica Forsk)
Authors: Prasad K Nagendra , Divakar Soundar , Shivamurthy Gyarahally R , Aradhya Somaradhya Mallikarjuna
Published: March 2005

Ipomoea aquatica Forsk, a green leafy vegetable that is a rich source of vitamins and amino acids with many health benefits, has been explored for the isolation and identification of its bioactive compounds. Activity‐guided repeated fractionation of a methanol extract on a silica gel column followed by an XAD column yielded a compound that exhibited antioxidant activity with an EC50 value of 83 ± 1.02 µg ml−1 reaction mixture. It also showed very strong lipid peroxidation‐inhibitory activity in a liposome model system with an EC50 value of 72.2 ± 0.9 µg ml−1. However, it showed negligible metal‐chelating activity. Based on UV, 2D nuclear magnetic resonance and gas chromatography/mass spectrometry studies, the compound was tentatively identified to be 7‐O‐β‐D‐glucopyranosyl‐dihydroquercetin‐3‐O‐α‐D‐glucopyranoside. This is the first report on the antioxidant properties of I aquatica leaf extracts. Copyright © 2005 Society of Chemical Industry
Viscous two‐fluid flows in perturbed unbounded domains
Authors: Pileckas K. , Socolowsky J.
Published: March 2005

Two stationary plane free boundary value problems for the Navier‐Stokes equations are studied. The first problem models the viscous two‐fluid flow down a perturbed or slightly distorted inclined plane. The second one describes the viscous two‐fluid flow in a perturbed or slightly distorted channel. For sufficiently small data and under certain conditions on parameters the solvability and uniqueness results are proved for both problems. The asymptotic behaviour of the solutions is investigated. For the second problem an example of nonuniqueness is constructed. Computational results of flow problems that are very close to the above problems are presented. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Performance measures in Friedreich ataxia: Potential utility as clinical outcome tools
Authors: Lynch David R. , Farmer Jennifer M. , Wilson Robert L. , Balcer Laura J.
Published: March 2005

Although several neuroprotective agents have been proposed as potential therapies in Friedreich ataxia (FA), clinical trials of their efficacy are limited by a lack of sensitive outcome measures. We assessed whether performance measures (nine‐hole peg test, the timed 25‐foot walk, and low‐contrast letter acuity) provide valid measures of disease status in FA. Scores for each measure correlated significantly with neurologic disability and disease duration. Rank correlations between scores for performance measures were moderate in magnitude, suggesting that the each test captures separate yet related dimensions of neurological function in FA. Linear regression models demonstrated that scores from the nine‐hole peg test and the timed 25‐foot walk (after reciprocal transformation) were predicted by age and triplet repeat length in patients with FA. In addition, comparison of the temporal courses of change for each performance measure demonstrated that scores from the timed 25‐foot walk change early in the course of FA, nine‐hole peg test scores change slowly over the full course of the disorder, and low‐contrast letter acuity scores change in the later stages of the disease. Thus, a composite scale derived from these performance measures may provide the best overall measure for assessing disease progression throughout the illness. © 2005 Movement Disorder Society
Test‐retest reliability of four questionnaires for patients with overactive bladder: The overactive bladder questionnaire (OAB‐q), patient perception of bladder condition (PPBC), urgency questionnaire (UQ), and the primary OAB symptom questionnaire (POSQ)
Authors: Matza Louis S. , Thompson Christine L. , Krasnow Joel , Brewster‐Jordan Jessica , Zyczynski Teresa , Coyne Karin S.
Published: March 2005

Aims

This study examined test‐retest reliability of four patient‐reported outcome measures for patients with overactive bladder (OAB): Overactive Bladder Questionnaire (OAB‐q), Patient Perception of Bladder Condition (PPBC), Urgency Questionnaire (UQ), and Primary OAB Symptom Questionnaire (POSQ).

Methods

Patients recruited from urology clinics were scheduled for two visits 2 weeks apart and completed all questionnaires at both visits. A demographic form was completed at Visit 1; and a treatment effect scale was completed at Visit 2. Test‐retest reliability was examined among stable patients using intraclass correlations (ICC), Spearman's correlations, paired t‐tests, Feldt's statistic, and kappas.

Results

A total of 47 patients enrolled (mean age = 66.0 years, 74.5% female), with 46 completing both visits; 35 were classified stable. Statistically significant correlations were present between Visits 1 and 2 (P < 0.05) for all subscales of the OAB‐q, UQ, and POSQ. Subscale ICCs were moderate to high (OAB‐q ≥ 0.83, UQ ≥ 0.46, POSQ continuous items ≥ 0.68). No significant differences between Visit 1 and 2 were noted, except for the OAB‐q symptom bother scale (change of 5.8 points on a 100‐point scale). The multi‐item subscales of the OAB‐q and the UQ demonstrated good internal consistency (Cronbach's alpha ≥ 0.83 for all subscales) across both visits. Test‐retest reliability of the PPBC was somewhat weaker than the other three measures, but still acceptable for use as a global, single‐item outcome measure.

Conclusions

The OAB‐q, POSQ, and UQ demonstrated good test‐retest reliability, with ICCs roughly equivalent or superior to those previously reported for 7‐day micturition diaries. Findings suggest that the four measures examined in this study demonstrate the necessary reproducibility for use as outcome measures for OAB treatments. © 2005 Wiley‐Liss, Inc.
Re: Slack M. Culligan P, Tracey M, Hunsicker K, Patel B, Sumeray M. 2004. Relationship of urethral retro‐resistance pressure to urodynamic measurements and incontinence severity. Neurourol Urodyn 23:109–14.
Authors: Petros P.E.
Published: March 2005

N Abstract
Algorithms for solving the conditional covering problem on paths
Authors: Lunday Brian J. , Smith J. Cole , Goldberg Jeffrey B.
Published: March 2005

Consider the conditional covering problem on an undirected graph, where each node represents a site that must be covered by a facility, and facilities may only be established at these nodes. Each facility can cover all sites that lie within some common covering radius, except the site at which it is located. Although this problem is difficult to solve on general graphs, there exist special structures on which the problem is easily solvable. In this paper, we consider the special case in which the graph is a simple path. For the case in which facility location costs do not vary based on the site, we derive characteristics of the problem that lead to a linear‐time shortest path algorithm for solving the problem. When the facility location costs vary according to the site, we provide a more complex, but still polynomial‐time, dynamic programming algorithm to find the optimal solution. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005.
Cell turnover of serrated adenomas
Authors: Ladas Spiros D , Kitsanta Panagiota , Triantafyllou Konstantinos , Tzathas Charalampos , Spiliadi Charis , Raptis Sotirios A
Published: March 2005

Serrated adenomas of the colon are characterized by epithelial neoplasia combining the architectural features of hyperplastic polyps and the cytological features of adenomas. Cell turnover, which is related to the malignant potential of these polyps, has not been thoroughly investigated. The aim of this study was to investigate epithelial cell proliferation, apoptosis, and oncoprotein expression in serrated adenomas. Twenty‐five hyperplastic polyps, 25 serrated adenomas, and 25 tubulovillous adenomas resected from the colons of 75 patients were studied by immunohistochemical staining using monoclonal antibodies against MIB‐1, Bcl‐2, Bax, p53, and the TUNEL method for the detection of apoptosis. In serrated adenomas, the proliferation rate was significantly lower than in tubulovillous adenomas in both the lower and the upper parts of the crypts, and higher than that of hyperplastic polyps. Apoptosis was also significantly lower in serrated than in tubulovillous adenomas, but higher than in hyperplastic polyps. p53 oncoprotein expression was significantly greater in both serrated and tubulovillous adenomas than in hyperplastic polyps. bcl‐2 protein expression was higher only in tubulovillous adenomas. Bax index was significantly different between tubullovillous and serrated adenomas, but the lowest values were observed in hyperplastic polyps. Serrated adenomas are highly proliferative polyps. They should be considered a biologically different entity from hyperplastic polyps. The intermediate features between serrated adenomas, hyperplastic polyps, and tubulovillous adenomas using the antibodies analysed in this study could have implications for the rate or the mechanism of development of malignancy in this type of polyp. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Pulmonary function impairment in children following hematopoietic stem cell transplantation
Authors: Wieringa J. , van Kralingen K.W. , Sont J.K. , Bresters D.
Published: March 2005

Background

Deterioration of pulmonary function after hematopoietic stem cell transplantation (SCT) is a well‐known late effect of this treatment, but the course of pulmonary function over time is less clear. The aim of our study was to establish both the prevalence and course of pulmonary function abnormalities in children following SCT.

Methods

Thirty‐nine of 106 patients, who visited a post‐SCT late effects clinic and who underwent a pulmonary function test (PFT) both before and at least twice after SCT were included in this study. Forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC), total lung capacity (TLC), and total lung diffusion capacity (TLCO) were determined and recorded as percentage predicted for age, sex, and length matched controls. Values of less than 80% of predicted were considered abnormal. Change in PFT parameters over time was determined by comparing the mean PFT parameter in our group at three different time points: pre‐SCT, ≤1 year post‐SCT (SCTpost1) and >1 year post‐SCT (SCTpost2).

Results

After SCT restrictive and/or diffusion abnormalities are most prevalent (45% and 76% at SCTpost1, respectively). A significant decrease of TLC (−9.7%) and TLCO (−20.3%) was observed during the first year after SCT, with improvement over time, but no normalization. Obstructive lung disease was less common (6% at SCTpost1). Clinical signs of lung function impairment were rare.

Conclusions

Restrictive and diffusion lung function disorders are common after SCT. They improve over time but do not normalize. As only a few patients with pulmonary function abnormalities had clinical signs of lung function impairment, the clinical relevance of performing long‐term follow‐up of PFT is questionable. © 2005 Wiley‐Liss, Inc.
Accelerated synthesis of poly(methyl methacrylate)‐b‐poly(vinyl chloride)‐b‐poly(methyl methacrylate) block copolymers by the CuCl/tris(2‐dimethylaminoethyl)amine‐catalyzed living radical block copolymerization of methyl methacrylate initiated with α,ω‐di(iodo)poly(vinyl chloride) in dimethyl sulfoxide at 90 °C
Authors: Percec Virgil , Guliashvili Tamaz , Popov Anatoliy V. , Ramirez‐Castillo Ernesto , Coelho Jorge F. J. , Hinojosa‐Falcon Luis A.
Published: March 2005

α,ω‐Di(iodo)poly(vinyl chloride)s [α,ω‐di(iodo)PVCs] with number‐average molecular weights ranging from 2100 to 20,000 and weight‐average molecular weight/number‐average molecular weight ratios ranging from 1.72 to 2.16 were synthesized through the single‐electron‐transfer/degenerative‐chain‐transfer mediated living radical polymerization of vinyl chloride initiated with iodoform and catalyzed by sodium dithionite in water at 25–35 °C. These α,ω‐di(iodo)PVCs were used as macroinitiators for the metal‐catalyzed living radical block copolymerization of methyl methacrylate to produce poly(methyl methacrylate)‐b‐poly(vinyl chloride)‐b‐poly(methyl methacrylate) block copolymers. By searching various copper derivatives, ligands, and solvents, it has been found that CuCl/tris(2‐dimethylaminoethyl)amine in dimethyl sulfoxide at 90 °C provides an accelerated method for the synthesis of block copolymers. Poly(methyl methacrylate)‐b‐poly(vinyl chloride)‐b‐poly(methyl methacrylate) block copolymers with number‐average molecular weights of 41,000–106,700 were produced by this method in 30–80 min. These reaction times were within the range of induction times exhibited when the same block copolymers were synthesized with CuCl/2,2′‐bipyridine in diphenyl ether at 90 °C. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1649–1659, 2005
Copolymerization of ethylene and cyclopentene with bis(β‐enaminoketonato) titanium complexes
Authors: Tang Li‐Ming , Duan Yi‐Qun , Pan Li , Li Yue‐Sheng
Published: March 2005

The copolymerizations of ethylene and cyclopentene with bis(β‐enaminoketonato) titanium complexes {[(Ph)NC(R2)CHC(R1)O]2TiCl2; R1 = CF3 and R2 = CH3 for 1a, R1 = Ph and R2 = CF3 for 1b; and R1 = t‐Bu and R2 = CF3 for 1c} activated with modified methylaluminoxane (MMAO) as a cocatalyst were investigated. High‐molecular‐weight copolymers with cis‐1,2‐cyclopentene units were obtained. The catalyst activity, cyclopentene incorporation, polymer molecular weight, and polydispersity could be controlled over a wide range through the variation of the catalyst structure and reaction parameters, such as the Al/Ti molar ratio, cyclopentene feed concentration, and polymerization reaction temperature. The complex 1b/MMAO catalyst system exhibited the characteristics of a quasi‐living ethylene polymerization and an ethylene–cyclopentene copolymerization and allowed the synthesis of polyethylene‐block‐poly(ethylene‐co‐cyclopentene) diblock copolymer. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1681–1689, 2005
Novel network morphology of poly(p‐oxybenzoyl)
Authors: Kimura Kunio , Kohama Shin‐ichiro , Kondoh Satomi , Uchida Tetsuya , Yamashita Yuhiko , Oohazama Takeshi , Sakaguchi Yoshimitsu
Published: March 2005

Polymerization of 4‐acetoxybenzoic acid (ABA) with 3,5‐diacetoxybenzoic acid (DABA) was examined to control the morphology of poly(p‐oxybenzoyl) (POB). Polymerizations were carried out at a concentration of 1.0% in an aromatic solvent Therm S‐1000® (mixture of dibenzyltoluene) at 320 °C. Polymerization of ABA yielded the POB fibrillar crystals, but the polymerization with DABA at a concentration in the feed (χf) of 0.10–0.15 afforded novel network structures comprised of spheres connected by fibrillar crystals. The diameter of the spheres prepared at χf of 0.15, which were 0.7 and 5.0 μm, showed bimodality. The network distance, fibril length, and fibril width were 6.1, 2.6, and 0.1 μm, respectively. They possessed high crystallinity. The network structure was formed as follows. Co‐oligomers were first precipitated in the beginning of the polymerization by liquid–liquid phase separation to form the microdroplets. The fibrillar crystals were formed in the coalesced spheres by the crystallization of oligomers induced by the increase of molecular weight. The fibrillar crystals connecting the spheres gradually appeared owing to the shrinkage of the spheres. The fibrillar crystals grew from the surface of the spheres with the crystallization of homo‐oligomers of 4‐oxybenzoyl units, and finally the network structure was completed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1624–1634, 2005
Enhancement of localization and confinement effects in quaternary group‐III nitride multi‐quantum wells on SiC substrate
Authors: Anceau S. , Lefebvre P. , Suski T. , Konczewicz L. , Hirayama H. , Aoyagi Y.
Published: March 2005

The competition between radiative and nonradiative recombination of electron‐hole pairs in (Al,In,Ga)N/(Al,In,Ga)N quantum wells of two different compositions and various well widths was investigated in order to understand the microscopic mechanisms of the highly intense light emission from this type of structures. By using time‐resolved photoluminescence, we have verified that one can adjust the compositions of the quaternaries so as to optimize the confinement effects and to minimize the built‐in electric field which is present in such hexagonal group‐III nitride based QWs. The role of local potential fluctuations in the quaternary alloy on the localization of carriers was studied and analyzed by measuring the photoluminescence energy, intensity and dynamics versus temperature. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Processing of novel SiC and group III‐nitride based micro‐ and nanomechanical devices
Authors: Foerster Ch. , Cimalla V. , Brueckner K. , Lebedev V. , Stephan R. , Hein M. , Ambacher O.
Published: March 2005

Micro‐ and nanoelectromechanical systems are being designed and intensively investigated for their use in various sensor applications. In this issue's Editor's Choice [1] micromechanical resonator beams with high fundamental frequencies were realized. The cover picture shows a scanning electron microscopy image of a 3C–SiC beam with middle electrode for capacitive read‐out as well as a finite element method simulation of the maximum oscillation amplitude.

The first author, Christian Förster, works on the epitaxial growth of hetero‐ and nanostructures based on wide band gap semiconductors and the processing of electronic and sensor devices in the Center for Micro‐ and Nanotechnologies of the Technical University Ilmenau, Germany.

The present issue of physica status solidi (a) contains Original Papers presented at the 7th International Workshop on Expert Evaluation & Control of Compound Semiconductor Materials & Technologies held in Montpellier, France, 1–4 June 2004. Further papers from EXMATEC 2004 are published in physica status solidi (c) 2, No. 4 (2005). (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
From ferromagnetism to spin glass magnetic structure: Mössbauer study of the ordered Fe0.75–xAl0.25+x alloys (x = 0, 0.025, and 0.05)
Authors: Delyagin N. N. , Erzinkyan A. L. , Parfenova V. P. , Rozantsev I. N.
Published: March 2005

Short‐range order, due to the strong interatomic Al–Fe interaction, is the key factor governing the unexpected quick change of the magnetic properties of Fe0.75–xAl0.25+x alloys over a narrow range of Al concentration, x = 0.0–0.05. The sharp transition from ferromagnetism to spin‐glass magnetic structure is the result of the generation of a high (non‐statistical) concentration of Fe sites with a large number of Al nearest‐neighbors. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Embedding with a Lipschitz function
Authors: Mendelson Shahar
Published: March 2005

We investigate a new notion of embedding of subsets of {−1,1}n in a given normed space, in a way which preserves the structure of the given set as a class of functions on {1, …, n}. This notion is an extension of the margin parameter often used in Nonparametric Statistics. Our main result is that even when considering “small” subsets of {−1, 1}n, the vast majority of such sets do not embed in a better way than the entire cube in any normed space that satisfies a minor structural assumption. © 2005 Wiley Periodicals, Inc. Random Struct. Alg., 2005
Survey propagation: An algorithm for satisfiability
Authors: Braunstein A. , Mézard M. , Zecchina R.
Published: March 2005

We study the satisfiability of randomly generated formulas formed byMclauses of exactlyKliterals overNBoolean variables. For a given value ofNthe problem is known to be most difficult when α =M/Nis close to the experimental threshold αcseparating the region where almost all formulas are SAT from the region where all formulas are UNSAT. Recent results from a statistical physics analysis suggest that the difficulty is related to the existence of a clustering phenomenon of the solutions when α is close to (but smaller than) αc. We introduce a new type of message passing algorithm which allows to find efficiently a satisfying assignment of the variables in this difficult region. This algorithm is iterative and composed of two main parts. The first is a message‐passing procedure which generalizes the usual methods like Sum‐Product or Belief Propagation: It passes messages that may be thought of as surveys over clusters of the ordinary messages. The second part uses the detailed probabilistic information obtained from the surveys in order to fix variables and simplify the problem. Eventually, the simplified problem that remains is solved by a conventional heuristic. © 2005 Wiley Periodicals, Inc. Random Struct. Alg., 2005
Exploring the relationship of emotional intelligence with physical and psychological health functioning
Authors: Tsaousis Ioannis , Nikolaou Ioannis
Published: March 2005

This study investigates the relationship of emotional intelligence (EI) characteristics, such as perception, control, use and understanding of emotions, with physical and psychological health. In the first study, 365 individuals filled in measures of EI and general health. It was hypothesized that EI would be negatively associated with poor general health. In the second study, 212 working adults completed the same measure of EI and another measure, which apart from the standard information regarding physical and psychological health, provided also information about other health related behaviours, such as smoking, drinking, and exercising. It was also hypothesized that EI would negatively correlate with smoking and drinking and positively correlate with exercising. The findings confirmed both hypotheses and provided further support on the claims that there is a relationship between EI and health functioning. Additionally, in a series of hierarchical regression analyses the unique contribution of each of the EI scales on the overall health score were investigated. The findings are discussed in the context of the importance of emotional competences on health and personal lifestyle, while implications for practice and directions for future research are proposed. Copyright © 2005 John Wiley & Sons, Ltd.
Computerized testing in large courses: A case study
Authors: Kremer John F.
Published: March 2005

Can computers help with one of the most persistent challenges of large classes: the accurate and efficient measurement of student learning?
Neutral phenotypes as network keystone species
Authors: Ikegami Takashi
Published: March 2005

The concept of network keystone species is proposed. A set of phenotypes constitute a network that acts as a functional keystone. When an ecosystem forms a large, complex network that changes temporally, it is generally difficult to tell which will become a keystone species. Based on simulations of abstract ecosystems, phenotypes were classified to show that neutral phenotypes, or slowly reproducing phenotypes, are candidates for keystone species. I show that the removal of neutral phenotypes breaks up an attractor state and produces significant impacts on the stability of an attractor, in spite of small population size. The effect of partial removal of neutral phenotypes, and the combinatorial effects of keystone species, are reported in detail.
In vitro activity of C‐20 methyltransferase, BchU, involved in bacteriochlorophyll c biosynthetic pathway in green sulfur bacteria
Authors: Harada Jiro , Saga Yoshitaka , Yaeda Yuki , Oh-oka Hirozo , Tamiaki Hitoshi
Published: March 2005

The activity of a methyltransferase, BchU, which catalyzes methylation at the C‐20 position of chlorin ring in the biosynthetic pathway of bacteriochlorophyll c, was investigated in vitro. The bchU gene derived from the photosynthetic green sulfur bacterium, Chlorobium tepidum, was overexpressed in Escherichia coli as a His‐tagged protein (His6‐BchU), and the enzyme was purified. In the presence of S‐adenosylmethionine, His6‐BchU methylated zinc bacteriopheophorbide d at the C‐20 position to give zinc bacteriopheophorbide c. Metal‐free bacteriopheophorbide d could not be methylated by the BchU, indicating that the central metal in the chlorin should be required for the recognition by the BchU.
Reducing neonatal mortality rate with nurse‐midwives
Authors: LEVY BARRY S. , WILKINSON FREDERICK S. , MARINE WILLIAM M.
Published: March 2005

Newborn health indices were measured before, during, and after a demonstration nurse‐midwife program introduced to relieve a health manpower shortage at a county hospital in rural California. During the program, prenatal care increased, and prematurity and neonatal mortality rate decreased at the county hospital. After the 3 year program, prenatal care decreased while prematurity rose from 6.6 to 9.8 per cent (p < 0.02) and neonatal mortality rate rose from 10.3 to 32.1 per 1,000 live births (p < 0.005). No significant changes occurred in the same indices for births elsewhere in the county throughout the period of study. It is concluded that the discontinuation of the nurse‐midwives'services was the major factor in these changes, and it is suggested that nurse‐midwives be used more extensively.
Vestibular fold flap for post‐cordectomy laryngeal reconstruction
Authors: Mamede Rui Celso Martins , Ricz Hilton Marcos Alves , Aguiar‐Ricz Lílian Neto , De Mello‐Filho Francisco Veríssimo
Published: March 2005

OBJECTIVES

The development of techniques causing fewer sequelae without compromising oncologic control has led to better phonation, breathing, and postoperative swallowing in patients submitted to cordectomy. The objective of the present study was to describe post‐cordectomy laryngeal reconstruction with a vestibular fold flap and to analyze the resulting laryngeal functions.

STUDY DESIGN

Prospective study.

METHODS

Ten patients, 9 males and 1 female, aged 45 to 75 years (mean, 64.5 years), were evaluated. The patients had squamous cell carcinomas in the glottic region and were treated surgically by laryngofissure and cordectomy with the use of a vestibular fold flap for laryngeal reconstruction. The patients were followed up for functional laryngeal analysis that consisted of videolaryngostrobos‐copy, endoscopic evaluation of swallowing, and voice recording for perceptive auditory analysis, and for computing purposes.

RESULTS

No patients depended on tracheostomy during the late postoperative period. No stenosis, anterior synechia, granuloma, or laryngocele were detected, although 1 patient developed immobility in the median position of the operated hemilarynx, which, however, was not sufficient to impair the respiratory function. No alterations in the pharyngeal phase of swallowing were observed by endoscopic evaluation. Using the GRBAS scale, we observed moderate (30%) and severe (20%) dysphonia in 50% of the patients and grade 1 dysphonia (40%) or normal (10%) dysphonia in the remaining ones. Computing analysis revealed the following mean values: fundamental frequency of 177.5 Hz, jitter 1.11%, and shimmer 7.04%.

CONCLUSIONS

We conclude that reconstruction with a vestibular fold flap permitted the maintenance of the laryngeal functions of breathing and airway protection during swallowing, as well as the maintenance of phonation function, providing perfect voice emission according to perceptive auditory or acoustic analysis in 1 patient and moderate or severe dysphonia in one half of the cases when technical faults occurred.
A systematic review of the diagnosis and treatment of primary hyperparathyroidism from 1995 to 2003
Authors: Ruda James M. , Hollenbeak Christopher S. , Stack Brendan C.
Published: March 2005

OBJECTIVE

To systematically review the current preoperative diagnostic modalities, surgical treatments, and glandular pathologies associated with primary hyperparathyroidism.

STUDY DESIGN

A systematic literature review.

RESULTS

Of the 20,225 cases of primary hyperpara‐thyroidism reported, solitary adenomas (SA), multiple gland hyperplasia disease (MGHD), double adenomas (DA), and parathyroid carcinomas (CAR) occurred in 88.90%, 5.74%, 4.14%, and 0.74% of cases respectively. Tc99m‐sestamibi and ultrasound were 88.44% and 78.55% sensitive, respectively, for SA, 44.46% and 34.86% for MGHD, and 29.95% and 16.20% for DA, respectively. Postoperative normocalcemia was achieved in 96.66%, 95.25%, and 97.69% of patients offered minimally invasive radio‐guided parathyroidectomy (MIRP), unilateral, and bilateral neck exploration (BNE). Intraoperative PTH assays (IOPTH) were helpful in approximately 60% of bilateral neck exploration conversion (BNEC) surgeries.

CONCLUSION

The overall prevalence of multiple gland disease (MGD and DA) was lower than often suggested by conventional wisdom. Furthermore, preoperative imaging was less accurate than it is often perceived for accurately imaging MGD. MIRP and UNE were more successful in achieving normo‐calcemia than is typically quoted. IOPTH was a helpful but not “fool‐proof” adjunct in parathyroid exploration surgery.

SIGNIFICANCE

These results support a greater role for the treatment of primary hyperparathyroidism using less invasive approaches. EMB rating: B‐3.
A novel laryngoscope instrument stabilizer for operative microlaryngoscopy
Authors: Armstrong William B. , Karamzadeh Amir M. , Crumley Roger L. , Kelley Timothy F. , Jackson Ryan P. , Wong Brian J. F.
Published: March 2005

OBJECTIVE

To evaluate and optimize the design of a removable and inexpensive internal stabilization device to reduce the effect of intention tremor during laryngeal microsurgery.

STUDY DESIGN AND SETTING

In this laboratory investigation, stabilizers were designed and constructed to allow a nonobstructing view of the surgical field, permit simple insertion and removal, and accommodate microsurgical instruments. Prototype stabilizers were tested by using a Dedo laryngoscope, a measurement grid, and video recording equipment, which recorded instrument tremor within the magnified operative field for later analysis. Physicians also rated instrument stability, mobility, visualization, and ease of use on a survey form.

RESULTS

Instrument tremor was reduced approximately 90%, with little obstruction of view of the surgical field. Instrument range of motion was reduced but improved rapidly as the stabilizer bar was moved further from the tip of the laryngoscope.

CONCLUSIONS

Use of a stabilization device in the laryngoscope lumen reduces instrument tremor and has the potential to improve surgical performance during laryngeal microsurgery. EBM rating: B‐3.
Evidence of naturally occurring wave‐wave interactions in the polar ionosphere and its relation to naturally enhanced ion acoustic lines
Authors: Strømme A. , Belyey V. , Grydeland T. , La Hoz C. , Løvhaug U. P. , Isham B.
Published: March 2005

In this paper we offer the first study of seldom‐recorded naturally occurring wave‐wave interactions in the polar ionosphere, using the first such data set acquired with the EISCAT Svalbard Radar (ESR). The simultaneous and co‐located observations of enhancements in the ion and plasma lines can only be explained in terms of wave‐wave interactions taking place within the scattering volume. These measurements strengthen previous indications that Langmuir turbulence triggered by a low energy electron beam associated with the aurora is probably the source of many of the Naturally Enhanced Ion Acoustic Lines (NEIAL) observed with incoherent scatter radars over the last decade.
Long‐term variation of surface phytoplankton chlorophyll a in the Southern Ocean during 1965–2002
Authors: Hirawake Toru , Odate Tsuneo , Fukuchi Mitsuo
Published: March 2005

The variation in the phytoplankton biomass over a decadal time scale, and its relationship with the Antarctic Circumpolar Wave (ACW) and climate change, has been poorly interpreted because of the limited satellite chlorophyll a (chl a) data compared with the physical parameters from satellite. We analyzed a long‐term chl a data set along the Japanese Antarctic Research Expedition (JARE) cruise tracks since 1965 to investigate inter‐annual variation of phytoplankton biomass. In the Southern Ocean, increasing trends of chl a and the spreading of higher chl a area to the north with 3–7 year cycles were found. Although relationships between the decadal change in chl a and climate change such as variation of sea ice extent and the El Niño are still obscure, large variation of primary production in proportion to the chl a is implied.
The relation between interannual storage and frequency of droughts, with particular reference to the Pantanal Wetland of South America
Authors: Clarke Robin T.
Published: March 2005

A large volume of natural storage within a drainage basin has a marked effect on its regime of hydrologic extremes. In this paper, the carry‐over effects from one year to the next that result from large interannual storage are quantified for the Ladário gauging site below the Pantanal, the world's largest wetland, in the drainage basin of the River Paraguay. The presence of carry‐over effects introduces correlation between extremes in successive years, with the consequence that commonly used methods for calculating the frequencies of extreme events, all of which assume that values in successive years are statistically independent, are no longer appropriate. When serial correlation between annual flood peaks at Ladário is allowed for, the estimated mean length of longest drought period in a 100‐year period is extended by two years. The possibility that other factors contribute to the serial correlation in Ladário flood peaks is considered: no evidence was found of correlation with ENSO events as defined in the literature.
Molecular nitrogen LBH band system far‐UV emissions of sprite streamers
Authors: Liu Ningyu , Pasko Victor P.
Published: March 2005

The time dependent optical emission model developed by Liu and Pasko (2004) is applied to studies of far‐UV emissions of sprite streamers due to N2 Lyman‐Birge‐Hopfield (LBH) band system. Modeling results indicate that the LBH emissions of sprite streamers at 70 km are generally stronger by up to a factor of 10 than those from the first negative band system of N2+, and experimental measurements of the ratio of these two emissions at sprite altitudes can be used to determine poorly known quenching altitude of the N2 (a1Πg) state.
Global observations of the land breeze
Authors: Gille Sarah T. , Llewellyn Smith Stefan G. , Statom Nicholas M.
Published: March 2005

Four‐times daily satellite wind observations from the QuikSCAT and ADEOS‐II tandem scatterometer mission are used to study the land/sea breeze circulation. These observations provide a global view of diurnal wind variations over the ocean. Results agree with frictional linear theory: winds follow an elliptical hodograph through the course of the day, but indicate that diurnal wind variations propagate offshore progressively like nonlinear gravity waves and are detectable several hundred kilometers from the coast.
Fractal properties of SYM‐H during quiet and active times
Authors: Wanliss James
Published: March 2005

Detrended fluctuation analysis was applied to the magnetic storm index SYM‐H for the epoch 1981–2002. The objective was to determine the characteristic fractal statistical differences, if any, between a quiet and active magnetosphere. The entire data set comprises over 11 million points that include numerous intervals that can be classified as quiet or active. For quiet intervals we required Kp ≤ 1 for 10,000 consecutive minutes. Similarly, to qualify as an active interval required Kp ≥ 4 for 10,000 consecutive minutes. All active intervals included magnetic storms. Detrended fluctuation analysis was applied to each of these intervals to obtain local scaling exponents. A clear difference in statistical behavior during quiet and active intervals is implied through analysis of the scaling exponents for the quiet and active intervals; active intervals generally have larger values of scaling exponents. This implies that although SYM‐H appears monofractal on shorter timescales, it is more properly described as a multifractional Brownian motion. An overall trend toward higher scaling exponents was also discovered for increasing magnetospheric activity, possibly implying an increase in organization with magnetospheric activity. The overall distribution of the scaling exponents for active intervals was Gaussian. For quiet intervals, however, it was bi‐Gaussian, perhaps indicative of different internal (magnetospheric) and external (solar wind) nonlinear forcings.