bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of Raman spectroscopy as an astrobiological tool in the exploration of Mars
Authors: Ellery Alex , Wynn‐Williams David , Parnell John , Edwards Howell G. M. , Dickensheets David
Published: June 2004

We describe how the exploration of the Martian environment would be considerably enhanced through the use of Raman spectroscopy. Furthermore, Raman spectroscopy is particularly suited for both mineralogical analysis of Martian rock and soil and for the detection of fossilised biota from former Martian micro‐organisms. We outline astrobiologically relevant features of the Martian environment and issues related to the detection of biotic residues. We further discuss the possibility of the emergence of photosynthetic bacteria on early Mars which may have left fossil evidence. We describe how Raman spectroscopy may be deployed for both astrobiological and mineralogical investigation, particularly in search of pigmented biomolecules, and describe the requirements for a spaceflight‐qualified version of a Raman spectrometer for deployment on Mars. Copyright © 2004 John Wiley & Sons, Ltd.
Micro‐Raman spectroscopy: a valuable tool for the investigation of extraterrestrial material
Authors: Hochleitner R. , Tarcea N. , Simon G. , Kiefer W. , Popp J.
Published: June 2004

The investigation of different samples of SNC (Shergotty–Nakhla–Chassigny) meteorites was chosen to test the ability of micro‐Raman spectroscopy to cope with extraterrestrial material. The following SNC meteorites were investigated: Sayh al Uhaymir 060, Dar al Gani 735, Dar al Gani 476, Northwest Africa 856, Los Angeles, Northwest Africa 1068 and Zagami. Pyrite as a hitherto undescribed phase in the picritic (olivine‐phyric) shergottite NWA 1068 and reduced carbon (e.g. graphite) and anatase in the shergottite Say al Uhaymir 060 are new findings for this class of meteorites. Copyright © 2004 John Wiley & Sons, Ltd.
Raman spectroscopy breaking terrestrial barriers!
Authors: Popp J. , Schmitt M.
Published: June 2004

This paper gives a summary of the Special Issue on ‘Raman spectroscopy breaking terrestrial barriers?’ It summarizes the papers collected and introduces to the field of Raman spectroscopy applied to planetary missions. The contributions in this issue convincingly prove that Raman spectroscopy will be essential for future planetary missions. Copyright © 2004 John Wiley & Sons, Ltd.
The construction of a firm's governance structure in a setting of uncertainty
Authors: O'Donoghue Erik J.
Published: June 2004

Why does the firm look the way it does? Why does it have the structures it has? In particular, what is the function of the board of directors? Many papers have tried, and failed, to link the board's structure to the performance of the firm. Might the board have an alternative rationale for existence? In this paper, I explore the possibility of the board being used as a signaling device. The management, having information about the state of the world the investor does not, constructs a signal (the board of directors) to promote efficiency in an uncertain world. The construction of the board signals the state of the world to the investor, reducing the uncertainty, and thereby attracting necessary capital to the firm. I then examine the size of the signal with respect to other key firm characteristics. I find that the size of the signal diminishes as investors become more concentrated. Copyright © 2004 John Wiley & Sons, Ltd.
Fundamental analysis of stocks by two‐stage DEA
Authors: Abad Cristina , Thore Sten A. , Laffarga Joaquina
Published: June 2004

Fundamental analysis of stocks links financial data to firm value in two consecutive steps: a predictive information link tying current financial data to future earnings, and a valuation link tying future earnings to firm value. At each step, a large number of causal factors have to be factored into the evaluation. To effect these calculations, we propose a new two‐stage multi‐criteria procedure, drawing on the techniques of data envelopment analysis. At each stage, a piecewise linear efficiency frontier is fitted to the observed data. The procedure is illustrated by a numerical example, analyzing some 30 stocks in the Spanish manufacturing industry in the years 1991–1996. Copyright © 2004 John Wiley & Sons, Ltd.
A new relative skill measure for games with chance elements
Authors: Dreef Marcel , Borm Peter , van der Genugten Ben
Published: June 2004

An interesting aspect of games is the relative extent to which a player can positively influence his results by making appropriate strategic choices. This question is closely related to the issue of how to distinguish between games of skill and games of chance. The distinction between these two types of games is definitely interesting from a juridical point of view.

In this paper we present a modification of an existing measure of the skill level of a game, which has served as a juridical tool for the classification of games. The main difference is that this new definition does not automatically classify incomplete information games without chance moves as games of skill. Copyright © 2004 John Wiley & Sons, Ltd.
Industry, management capabilities and firms' competitiveness: An empirical contribution
Authors: Molina Miguel Acosta , del Pino Idaira Barrios , Rodríguez Alicia Correa
Published: June 2004

The aim of this paper is to contribute to the knowledge of strategic factors that explain the competitive position reached by firms in their activity sector.

We have used a survey carried out in 1999 on 287 executives that belong to the service sector in the province of Santa Cruz de Tenerife. We have analysed the differential factors that distinguish the strategic performance of competitive vis‐à‐vis non‐competitive firms, by jointly assessing the variables representative of the sector (five competitive forces defined by Porter) and variables of an internal feature. Finally, we have moved the level of analysis from the industry to the firm; specifically, we have focused on managerial capabilities due to the significant role played by managers in the strategic decision‐making process.

The use of cluster analysis to classify firms depending on their degree of competitiveness and the application of the See5 induction algorithm of rules and decision trees to determine the differential factors that distinguish competitive from non‐competitive firms, provide a methodological framework for the most significant contributions of this work. Copyright © 2004 John Wiley & Sons, Ltd.
Delegation in first‐price all‐pay auctions
Authors: Konrad Kai A. , Peters Wolfgang , Wärneryd Karl
Published: June 2004

In a first‐price all‐pay auction buyers have an incentive to delegate the bidding to agents and to provide these agents with incentives to make bids that differ from the bids the buyers would like to make. Both buyers are better off in this strictly non‐cooperative delegation equilibrium and the delegation contracts are asymmetric, even if the buyers and the auction are perfectly symmetric. Copyright © 2004 John Wiley & Sons, Ltd.
The economics of managerialism and the drive for efficiency in policing
Authors: Drake Leigh M. , Simper Richard
Published: June 2004

The UK has recently proposed to develop a set of criteria whereby the economic analysis of police force efficiency is to be made standard. This follows a strategy of aiming for improvement through managerialism and best value performance indicators, similar to those implemented by US police forces after the Government Performance and Results Act 1993. In this paper we attempt to put this recent development of efficiency targeting into a UK historical/evolutionary context and provide one of the first attempts to use data envelopment analysis to analyse the allocative, as well as technical efficiency, of police forces in England and Wales. Copyright © 2004 John Wiley & Sons, Ltd.
Sewer plant operating efficiency, patronage, and competition
Authors: Southwick Lawrence
Published: June 2004

Sewer treatment plants in New York State, US, are studied for efficiency and economies of scale. Substantial economies of scale are found. The degree of inefficiency for each plant is then computed and this inefficiency is related to the degree of market concentration in that county. The result found is that greater concentration induces a reduction in efficiency. This is argued to be consistent with the Tiebout Hypothesis. Copyright © 2004 John Wiley & Sons, Ltd.
Proxy contest, board reelection, and managerial turnover—yes, the proxy contest outcome matters
Authors: Yen Gili , Chen Ching‐Lung
Published: June 2004

In a previous study based on a matched sample analysis, it is found that in Taiwan top management turnover rate for the listed firms in the presence of a proxy contest is much higher than the ones without a proxy contest. In other words, the hypothesis of job security has gained empirical support. Taking account of the proxy contest outcomes, the present study extends the sample years, i.e. 1994–1999, to further examine the impact of proxy contest on managerial turnover. In conformity with expectations, the major empirical findings can be summarized as follows: the highest turnover rate of top management is observed in the firms of which the dissidents win majority seats; the second highest turnover rate is observed in the firms of which the dissidents win some seats; whereas the lowest turnover rate is observed in the firms of which the dissidents win no seats. Empirical findings of this kind provide further support to the view that proxy contest has played an effective monitoring role in disciplining incumbent management. Copyright © 2004 John Wiley & Sons, Ltd.
Top executive turnovers: Separating decision and control rights
Authors: Neumann Robert , Voetmann Torben
Published: June 2004

This paper examines the relationship between performance and top executive turnovers using a sample of 81 turnovers and matching companies listed on the Copenhagen Stock Exchange. We find that poor market performance increases the probability of management replacements and that forced layoffs are value‐increasing events while voluntary resignations are value‐decreasing events. Large shareholders as active monitors, or part of corporate control, are not exhibited in the results. If large shareholders have any influence on CEO turnovers it is not revealed in our data. Indeed, separating control rights from decision rights does not appear to affect managerial turnovers. Copyright © 2004 John Wiley & Sons, Ltd.
Bent knees and tiptoeing: Late manifestations of end‐stage Parkinson's disease
Authors: Djaldetti Ruth , Hellmann Mark , Melamed Eldad
Published: June 2004

We describe a unique gait phenomenon of bent knees in 9 patients with idiopathic Parkinson disease (mean age, 73.1 ± 11.1 years), 3 of whom also manifested tiptoeing. The bent‐knee posture appeared only during ambulation; in the recumbent position, full or nearly full extension was possible in all patients. The abnormality emerged after long‐standing disease (6–23 years from onset) and failed to respond to dopaminergic treatment. Most of the patients also had bent spine (camptocormia). The pathogenesis of these phenomena are unknown, but they might represent a rare type of dystonia.© 2004 Movement Disorder Society
Audiovisual cues can enhance sit‐to‐stand in patients with Parkinson's disease
Authors: Mak Margaret K.Y. , Hui‐Chan Christina W.Y.
Published: June 2004

We investigated whether preparatory signals, in the form of audiovisual cues, could enhance the performance of sit‐to‐stand (STS) in Parkinson's disease (PD) patients. Fifteen patients and fifteen control subjects similar in age, gender, weight, and height were examined. All subjects were instructed to carry out STS under self‐initiated and cue‐initiated conditions. A PEAK Motion Analysis System and two force plates were synchronized to record kinematic and kinetic data. In patients with PD, the addition of audiovisual cues was found to increase hip flexion and knee extension torques and decrease the time‐to‐peak joint torques, as well as increase peak horizontal and vertical velocities of the body center of mass and decrease the time taken to complete STS. Consequently, the performance of STS in these patients approached that of control subjects. In fact, during cue‐initiated STS, no difference was found between the patient and control groups for the time‐to‐peak of all joint torques, the peak horizontal and vertical velocities, and the time taken to complete STS. Our findings thus demonstrated that audiovisual cues were effective in enhancing STS in patients with PD. These feed‐forward signals could have enhanced the defective motor preparatory phase, thus leading to improved performance of the STS task. These findings provide a scientific basis for the use of audiovisual signals to enhance STS performance in patients with PD. © 2004 Movement Disorder Society
Hemiballismus from a parietal stroke in a Parkinson patient
Authors: Al‐Yacoub Motasem , Friedman Joseph H. , Fernandez Hubert H.
Published: June 2004

Stroke‐induced hemiballismus (HB) has been reported to improve motor function in people with Parkinson's disease (PD). We report on a patient who developed HB from a parietal infarct. The HB was improved by very low‐dose clozapine but the HB did not improve the parkinsonism. This suggests that HB itself, whether from a lesion in the subthalamic nucleus or elsewhere, is not what improves motor function in PD; instead, the physiological function of the damaged structure is the determining factor. © 2004 Movement Disorder Society
An urge to move with L‐thyroxine: Clinical, biochemical, and polysomnographic correlation
Authors: Tan Eng‐King , Ho Su‐Chin , Koh Leonard , Pavanni Ratnagopal
Published: June 2004

We report on the cause and effect relationship of restless legs syndrome (RLS) with L‐thyroxine treatment in a hypothyroid patient with low serum ferritin. Upon challenge and withdrawal of L‐thyroxine, there was a significant change in the International Restless Legs Syndrome Study Group severity score (26/40 to 6/40), the periodic limb movements (PMLS) index (20/hour to 10/hour), the number of arousals due to PLMS (59 to 22), sleep efficiency (74 to 85%), and biochemical parameters. RLS symptoms can complicate thyroxine replacement in at‐risk hypothyroid patients with low serum ferritin. Early diagnosis and iron replacement could significantly reduce patient morbidity. © 2004 Movement Disorder Society
Assuring interrater reliability for the UPDRS motor section: Utility of the UPDRS teaching tape
Authors: Goetz Christopher G. , Stebbins Glenn T.
Published: June 2004

We assessed rates of successful certification on the motor section of the Unified Parkinson's Disease Rating Scale (UPDRSm) after training with the UPDRS Teaching Tape. The most frequently used clinical scale for PD is the UPDRS, and most clinical trials rely on the motor examination as the primary outcome measure. Whereas the Movement Disorder Society's UPDRS Teaching Tape has been used widely as a training format, outcome data are lacking. We examined data sets from four multicenter studies that required raters to pass the certification exercise of the UPDRS Teaching Tape. Raters viewed the Teaching Tape showing examples of all rating levels for all items (38 minutes), and then took the certification exercise, rating 4 subjects with PD (20 minutes). Certification required scores on all 4 subjects that fit within the 95% confidence interval range established by three experts. We calculated the numbers of raters successfully certified after one or more rating attempts. Only one‐half of 226 raters that participated successfully completed certification on their first attempt, but all completed by the third attempt. North American raters scored better than Europeans raters. The most difficult case to rate was the subject with the least impairment. Standardized methods for training UPDRSm application are essential to ensure that raters use the scale uniformly. Raters have the greatest difficulty with the mildest impairment, making training especially important to studies of early PD. © 2004 Movement Disorder Society
Transient parkinsonism: Induced by progesterone or pregnancy?
Authors: Demirkiran Meltem , Aslan Kezban , Bicakci Sebnem , Bozdemir Hacer , Özeren Ali
Published: June 2004

We report on the development of transient parkinsonism after progesterone injection in a pregnant patient with a risk of abortion. Etiological possibilities are discussed, including pregnancy itself, possible toxic effects of the dead fetus, and progesterone injection. Progesterone‐induced parkinsonism seems the most likely diagnosis in this case. © 2004 Movement Disorder Society
Prevalence of tremor in multiple sclerosis and associated disability in the Olmsted County population
Authors: Pittock Sean J. , McClelland Robyn L. , Mayr William T. , Rodriguez Moses , Matsumoto Joseph Y.
Published: June 2004

We applied a clinical tremor rating scale and measures of disability to 200 of 201 multiple sclerosis patients from a prevalence cohort in Olmsted County, Minnesota. In a community‐based sample, tremor was found clinically in 51 (25%) patients, although only 6 (3%) patients had severe tremor. Within the population as a whole, tremor was strongly associated with impairment disability and handicap. © 2004 Movement Disorder Society
Comparison of diffusion‐weighted imaging and [123I]IBZM‐SPECT for the differentiation of patients with the Parkinson variant of multiple system atrophy from those with Parkinson's disease
Authors: Seppi Klaus , Schocke Michael F.H. , Donnemiller Eveline , Esterhammer Regina , Kremser Christian , Scherfler Christoph , Diem Anja , Jaschke Werner , Wenning Gregor K. , Poewe Werner
Published: June 2004

Both dopamine D2 receptor (D2R) binding single‐photon emission computed tomography (SPECT) with [123I]iodobenzamide (IBZM) and diffusion‐weighted imaging (DWI) have been shown to contribute to the differential diagnosis of patients with the Parkinson variant of multiple system atrophy (MSA‐P) and Parkinson's disease (PD). We aimed to compare these two routinely available functional imaging modalities in differentiating patients with MSA‐P from PD. For this purpose, results obtained by DWI and IBZM‐SPECT were intraindividually compared in a cross‐sectional study of 15 MSA‐P and 17 PD patients matched for age and disease duration. The activity ratios of striatal to frontal cortex uptake (S/FC ratio) were used as a semiquantitative measure of the relative density of basal ganglia dopamine receptors labeled by IBZM. Regional apparent diffusion coefficients (rADC) were determined in the striatum. MSA‐P patients had significantly lower S/FC ratios and significantly higher striatal rADCs than both PD patients and healthy volunteers. There were no significant differences in S/FC ratios and striatal rADC between PD patients and healthy volunteers. Sensitivity of IBZM‐SPECT versus DWI for the differentiation of MSA‐P from PD was 80% versus 93%, specificity 71% versus 100%, the predictive accuracy 75% versus 97%, the positive predictive value 71% versus 100%, and the negative predictive value 80% versus 94%. Striatal rADCs had a significant higher overall predictive accuracy than D2R binding with IBZM. In summary, our data suggest that DWI may be more accurate compared to IBZM‐SPECT in the differential diagnosis of MSA‐P versus PD. © 2004 Movement Disorder Society
Brain parenchyma sonography detects preclinical parkinsonism
Authors: Walter Uwe , Klein Christine , Hilker Ruediger , Benecke Reiner , Pramstaller Peter P. , Dressler Dirk
Published: June 2004

Substantia nigra (SN) hyperechogenicity on brain parenchyma sonography (BPS) is highly characteristic for idiopathic PD. We studied 7 symptomatic and 7 asymptomatic parkin mutation carriers (PMC) from a large kindred with adult‐onset parkinsonism. BPS revealed larger SN echogenic sizes in PMC with parkin mutations on both alleles (homozygous, compound‐heterozygous), compared to PMC with only one mutated allele (Mann–Whitney U test, P = 0.007). In symptomatic PMC, larger SN echogenic size was correlated with younger age at onset of the disease (Spearman rank correlation, Rho = −0.937, P = 0.002) but not with age, disease duration, or disease severity. BPS demonstrated SN hyperechogenicity, in concordance with abnormal nigrostriatal 18F‐dopa positron emission tomography (PET), in all symptomatic and 3 asymptomatic PMC. In 2 asymptomatic PMC, PET and BPS were normal. However, in another 2 asymptomatic PET‐normal PMC, SN hyperechogenicity could be detected. Data suggest SN hyperechogenicity as an early marker to detect preclinical parkinsonism. © 2004 Movement Disorder Society
Neuronal activity in the globus pallidus of multiple system atrophy patients
Authors: Pereira Luiz C.M. , Palter Vanessa N. , Lang Anthony E. , Hutchison William D. , Lozano Andres M. , Dostrovsky Jonathan O.
Published: June 2004

The pathophysiological changes in neural activity that characterize multiple system atrophy (MSA) are largely unknown. We recorded the activity of pallidal neurons in 3 patients with clinical and radiological features of MSA who underwent unilateral microelectrode‐guided pallidotomy for disabling parkinsonism. Findings in these patients were compared with 4 control patients with a clinical diagnosis of Parkinson's disease (PD). The position, firing rates, and firing patterns of single neurons in the pallidal complex were analyzed in both MSA and PD patients. The mean spontaneous firing rate of neurons in the internal segment of the globus pallidus internus (GPii) was significantly lower in MSA than in PD patients. There were no significant differences between MSA and PD patients, however, in firing rates of neurons in the external globus pallidus (GPe) or in the external segment of GPi (GPie). In addition, no significant differences in firing pattern were found between MSA and PD patients. In conclusion, this study has shown that firing rates of neurons in GPii but not in GPie and GPe are different in MSA patients compared with that in PD patients, a finding that may reflect the poor clinical results of pallidotomy reported in patients with MSA. © 2004 Movement Disorder Society
A foot deformity from a Romano‐British cemetery at Gloucester, England, and the current evidence fortalipesin palaeopathology
Authors: Roberts C. A. , Knüsel C. J. , Race L.
Published: June 2004

A male skeleton from the Romano‐British site at Kingsholm, Gloucester, is described with abnormalities in the humerus, femur, tibia, fibula and foot. Computed tomography of the femora to enable cross‐sectional analysis suggested altered normal gait to compensate for the deformity. Differential diagnoses are considered and a diagnosis of clubfoot deformity is suggested. Palaeopathological evidence for clubfoot is rare in the literature but the cases reported to date are reviewed. Copyright © 2004 John Wiley & Sons, Ltd.
Molecular identification and characterization of Mycobacterium tuberculosis complex in ancient Egyptian mummies
Authors: Zink A. R. , Sola C. , Reischl U. , Grabner W. , Rastogi N. , Wolf H. , Nerlich A. G.
Published: June 2004

A considerable number of molecular studies have provided evidence for the presence of Mycobacterium tuberculosis complex (MTB) DNA in ancient skeletal and mummified material. Moreover first studies on the differentiation of sub‐types of the MTB (M. tuberculosis, M. bovis, M. africanum, M. microti, M. canettii) have successfully been performed on ancient tissue samples. In our present study we extend previous analyses and investigate bone and soft tissue samples from 118 ancient Egyptian mummies and skeletons from the Pre‐ to Early Dynastic site of Abydos and different tomb complexes in Thebes West, which were built and used between the Middle and New Kingdom until the Late Period (c. 2050–500 BC). The samples were tested for the presence of MTB DNA and further identified by spoligotyping. Twenty‐six samples provided molecular evidence for the presence of ancient mycobacterial DNA by amplification of a 123 base pair fragment of the repetitive element IS6110. Out of the 26 positive samples, 12 provided a complete spoligotyping signature, which was compared to an international database. Ten further cases showed an incomplete, patchy hybridization pattern, while in four cases no spoligotyping signature could be obtained. Interestingly, they all show either a M. tuberculosis or M. africanum pattern, but none revealed a M. bovis specific pattern. In the material from a Middle Kingdom tomb (used exclusively between c. 2050–1650 BC) several samples revealed a M. africanum type specific spoligotyping signature, while samples from later periods provided patterns typical for M. tuberculosis. This study clearly shows that spoligotyping can be used for the characterization of members of the MTB in historic tissue samples. In addition, our results do not support the theory that M. tuberculosis originated from the M. bovis type. Copyright © 2004 John Wiley & Sons, Ltd.
The phylogenetic significance of the Middle Pleistocene Narmada hominin cranium from central India
Authors: Cameron D. , Patnaik R. , Sahni A.
Published: June 2004

A parsimony analysis of the Narmada cranium from central India and a number of other demes and species ofHomoconcludes that the Narmada hominin shares a closer relationship with the European Steinheim specimen, than with AsianH. erectusorH. pekinensis. This suggests that the population represented by the Narmada cranium is likely to have had its origins in Europe rather than in Asia. Overall the available evidence supports an ‘Out of Africa’ scenario, as the early Asian hominins belong to a distinct clade which has no extant descendants and thus appear to represent an evolutionary ‘dead end’. The later African and European hominins are defined by a clade including earlyH. sapiensfrom Africa. The main difference between these two distinct clades is that theH. erectuslineage is defined by increasing degrees of neuro‐orbital disjunction associated with increased anterior cranial base extension, while the lineage leading to earlyH. sapiensis characterized by the opposite condition of reduced neuro‐orbital disjunction associated with increased anterior cranial base flexion. While there is also evidence of differential patterns of head and neck musculature between these two clades, they are of secondary importance. Preliminary dating of bovid remains found in association with the hominin cranium by the gamma spectrometric U‐series dating technique suggests a tentative minimum age of not less than 236,000 years. This is in agreement with evidence from biostratigraphical studies of the Boulder Conglomerate, which place these deposits in the Middle Pleistocene. Copyright © 2004 John Wiley & Sons, Ltd.
Fabrication and characterization of nylon 6/foliated graphite electrically conducting nanocomposite
Authors: Weng Wengui , Chen Guohua , Wu Dajun , Chen Xiangfeng , Lu Jinrong , Wang Pingping
Published: June 2004

In this study, the nylon 6/foliated graphite (FG) electrically conducting nanocomposites with a low percolation threshold of less than 0.75 vol % have been prepared via an in situ polymerization approach in the presence of FG nanosheet filler. Based on laser counting, scanning electron microscopy, transmission electron microscopy, and X‐ray diffraction characterization techniques, the structures and morphologies of the nanoscale filling particles and the resulting nanocomposites were examined. Using percolation theory, the conductivity behavior of the nanocomposite samples were modeled and analyzed. Through the use of mean‐field and excluded volume approaches, it was demonstrated that the experimentally observed percolation threshold values could be approximately estimated, and a correlation between the percolation threshold and the aspect ratio of FG particles could be quasi‐quantitatively established. Also, preliminary studies on the effects of FG nanosheets on the thermal properties of the host nylon 6 were performed. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2844–2856, 2004
Relationships between the molecular architecture, crystallization capacity, and miscibility in poly(butylene terephthalate)/polycarbonate blends: A comparison with poly(ethylene terephthalate)/polycarbonate blends
Authors: Marchese Paola , Celli Annamaria , Fiorini Maurizio
Published: June 2004

Poly(butylene terephthalate) (PBT)/polycarbonate (PC) samples, prepared via reactive blending in the presence of Ti‐ and Sm‐based catalysts, resulted in block copolymers whose block length decreased as the mixing time increased. A single homogeneous amorphous phase occurred when the blocks had monomeric sequences shorter than 10 units. Otherwise, a crystalline phase of PBT developed. Also, in poly(ethylene terephthalate) (PET)/PC blends previously studied, the miscibility was strictly correlated with the crystallizability of the system. Therefore, the miscibility of the PBT/PC and PET/PC blends was compared with respect to the tendency of the PBT and PET blocks to crystallize under isothermal conditions. The crystallization rate of the PBT/PC copolymers was faster than that of the PET/PC copolymers with similar block lengths. Accordingly, the minimum crystallizable sequence length of the PBT blocks was shorter than that of the PET blocks (18 vs 31 monomeric unit sequences). This behavior was interpreted as an effect of the more flexible PBT units, which had a greater tendency to fold and crystallize than the PET units. Therefore, PBT, the blocks of which tended to crystallize even if they were very short and phase‐separated, was characterized by a poorer compatibility with PC than that of PET. As a result, the block size had a fundamental role in determining the crystallizability and, therefore, phase behavior of the semicrystalline block copolymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2821–2832, 2004
Effects of poly[styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene] on the charge distributions of low‐density polyethylene/polystyrene blends
Authors: Kim Tae Young , Kim Dong Myung , Kim Won Jung , Lee Tae Hee , Suh Kwang S.
Published: June 2004

The effect of the triblock copolymer poly[styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene] (SEBS) on the formation of the space charge of immiscible low‐density polyethylene (LDPE)/polystyrene (PS) blends was investigated. Blends of 70/30 (wt %) LDPE/PS were prepared through melt blending in an internal mixer at a blend temperature of 220 °C. The amount of charge that accumulated in the 70% LDPE/30% PS blends decreased when the SEBS content increased up to 10 wt %. For compatibilized and uncompatibilized blends, no significant change in the degree of crystallinity of LDPE in the blends was observed, and so the effect of crystallization on the space charge distribution could be excluded. Morphological observations showed that the addition of SEBS resulted in a domain size reduction of the dispersed PS phase and better interfacial adhesion between the LDPE and PS phases. The location of SEBS at a domain interface enabled charges to migrate from one phase to the other via the domain interface and, therefore, resulted in a significant decrease in the amount of space charge for the LDPE/PS blends with SEBS. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2813–2820, 2004
Acute respiratory distress due to fibrosarcoma of the carina in a child
Authors: Savas Cagri , Candir Ozden , Ozguner Faruk
Published: June 2004

We report a 12‐year‐old boy with primary bronchopulmonary fibrosarcoma (PBPF). He was misdiagnosed a having asthma until he presented with acute respiratory distress syndrome. Chest x‐ray showed atelectasis of the right lung. Bronchoscopy performed to rule out foreign body inhalation revealed a friable mass obstructing the right main bronchus. Successful treatment was achieved with surgical resection of the lesion followed by radiotherapy and chemotherapy. Pediatr Pulmonol. 2004; 38:355–357. © 2004 Wiley‐Liss, Inc.
Recurrent respiratory papillomatosis in a survivor of extreme prematurity
Authors: Lee S.L. , Hui Y.
Published: June 2004

Recurrent respiratory papillomatosis (RRP) is a rare disease in children. Previous reports suggested that prematurity and early age of presentation were poor prognostic factors. We report on a 24‐week premature infant who presented with stridor, weak cry, and hoarseness of voice at age 9 months (corrected age), in whom the diagnosis of RRP was not made until age 21 months (corrected age). Laser excision of RRP was subsequently performed, and the child is still surviving at age 2.5 years. RRP should be considered in the differential diagnosis of airway problems in survivors of extreme prematurity; the prognosis is not uniformly poor in premature infants. Pediatr Pulmonol. 2004; 38:352–354. © 2004 Wiley‐Liss, Inc.
Preoperative polysomnograms and infant pulmonary function tests do not predict prolonged postoperative mechanical ventilation in children following scoliosis repair
Authors: Yuan Nanci , Skaggs David L. , Davidson Ward Sally L. , Platzker Arnold C.G. , Keens Thomas G.
Published: June 2004

Our objective was the identification of children with scoliosis at higher risk of prolonged postoperative mechanical ventilation (MV) permits improved pre‐ and perioperative respiratory care to reduce postoperative complications. Pulmonary function testing (PFT) predicts prolonged postoperative MV in children who can reliably perform PFT, but some children cannot perform PFT. The objective of this study was to determine if polysomnography (PSG) or infant pulmonary function testing (IPFT) could predict prolonged postoperative MV (defined as MV >3 days) in children undergoing scoliosis surgery who could not reliably perform PFT. We studied 110 patients (age range, 10.8 ± 4.9 [SD] years) who had preoperative PSG, and 18 patients (age range, 4.0 ± 2.9 [SD] years) who had preoperative IPFT prior to undergoing any type of scoliosis repair by the Children's Hospital of Los Angeles Division of Orthopedic Surgery from January 1990– July 2001. The following information was reviewed and correlated: preoperative PSG parameters (baseline and nadir S, baseline and peak P, and apnea hypopnea index [AHI]), preoperative IPFT parameters (respiratory system compliance [Crs], respiratory system resistance [Rrs], tidal volume [VT], and FRC), and length of postoperative MV. Twenty‐seven patients (25%) who had PSG and 5 patients (28%) who had IPFT required postoperative MV >3 days. There was no association between baseline and nadir S ≤ 92%, baseline and peak P, or AHI, and length of postoperative MV. There was no association between IPFT (Crs, Rrs, VT, and FRC) and length of postoperative MV. We conclude that neither PSG nor IPFT can predict the need for prolonged postoperative MV following scoliosis surgery in children who could not reliably perform PFT. © 2004 Wiley‐Liss, Inc.
Antigen detection for the diagnosis of pneumonia
Authors: Nunes Altacílio A. , Camargos Paulo A.M. , Costa Petrônio R. , Campos Maria Tereza K.
Published: June 2004

Streptococcus pneumoniae and Haemophilus influenzae type b are the main agents of bacterial community‐acquired pneumonia in developing countries, although a definite etiologic diagnosis cannot be established in most cases. This study was carried out to assess the performance of a latex particle agglutination test (LPAT) from a commercial kit (Slidex Méningite Kit™, BioMérieux, France) in diagnosing pneumococcal and H. influenzae type b pneumonia. One hundred and seven children (45 ill subjects and 62 healthy controls) were enrolled. All 45 cases had a presumptive diagnosis of bacterial pneumonia based on clinical (WHO criteria), laboratory (white blood cell count ≥15.000/mm3, polymorphonuclear leukocytes ≥70%, bands ≥500/mm3, and C‐reactive protein ≥40 mg/l), and radiological findings, i.e., two or more positive points in the scoring system described by Khamapirad and Glezen (Semin Respir Infect 1987;2:130–144). Clinical, laboratory, and radiological assessments were performed in a blinded manner. LPAT was performed in urine samples after concentration through an ethanol‐acetone solution. Sensitivity, specificity, and positive and negative predictive values were 77.3% (95% CI, 61.8–88.0%), 90.3% (95% CI, 79.5–96.0%), 85.0% (95% CI, 69.5–93.8%), and 84.8% (95% CI, 73.4–92.1%), respectively. Results suggest that LPAT is a useful diagnostic tool for the etiologic diagnosis of S. pneumoniae and H. influenzae type b pneumonia, especially in the developing world. Pediatr Pulmonol. © 2004 Wiley‐Liss, Inc.
Inhaled fluticasone dipropionate decreases levels of nitric oxide in recurrenty wheezy infants
Authors: Moeller Alexander , Franklin Peter , Hall Graham L. , Turner Steve , Straub Daniel , Wildhaber Johannes H. , Stick Stephen M.
Published: June 2004

We examined the effect of inhaled fluticasone diproprionate (FDP) on symptoms, lung function (FEV0.5), and exhaled nitric oxide (FeNO) in infants with recurrent wheeze and raised FeNO. Thirty‐one infants aged 6–19 months (mean, 12.7 months; 12 girls) completed the study. All infants had a history of recurrent wheeze and a parental history of atopy. All children had raised FeNO, as determined by an offline tidal breathing technique prior to randomization. Lung function and FeNO were assessed before and after 4 weeks of treatment with FDP or placebo. The parents recorded daily symptoms during the treatment period. Sixteen infants received FDP and 15 the placebo for 4 weeks. At completion of the study, infants treated with FDP had a significant reduction in FeNO (35.0 ppb to 16.5 ppb) compared to those that received placebo (35.2 ppb to 30.2 ppb) (P = 0.05). Small increases in FEV0.5 were observed in both groups, but these changes were not different between groups (P = 0.8). Symptom scores were not significantly different in either group following the intervention. We showed that a moderate dose of inhaled FDP reduces levels of FeNO, a potential marker of airway inflammation, even in the absence of significant changes in lung function and symptoms. © 2004 Wiley‐Liss, Inc.
Childhood asthma: Exhaled markers of airway inflammation, asthma control score, and lung function tests
Authors: Rosias Philippe P.R. , Dompeling Edward , Dentener Mieke A. , Pennings Herman J. , Hendriks Han J.E. , Van Iersel Monique P.A. , Jöbsis Quirijn
Published: June 2004

Exhaled markers of airway inflammation become increasingly important in the management of childhood asthma. The aims of the present study are: 1) to compare exhaled markers of inflammation (nitric oxide, carbon monoxide, and acidity of breath condensate) with conventional asthma measures (lung function tests and asthma control score) in childhood asthma; and 2) to investigate the detectability of albumin, CRP, IL‐6, IL‐8, TNF‐alpha, sICAM‐1, and sTNF‐R75 in the exhaled breath condensate (EBC) of asthmatic children. Thirty‐two children with mild to moderate persistent asthma and healthy controls aged 6–12 years were studied. We measured exhaled NO and CO, and subsequently EBC was collected. Inflammatory mediators in EBC were measured using an enzyme‐linked immunosorbent assay. Respiratory symptoms and asthma control were assessed using the asthma control questionnaire (ACQ) of Juniper et al. (Eur Respir J 1999;14:902–907). Exhaled NO showed a significant correlation with exhaled CO (r = 0.59,P < 0.05) and FEV1(r = −0.59,P < 0.05), but not with ACQ score (r = 0.48,P = 0.06). Exhaled CO was correlated with prebronchodilator FEV1(r = −0.45,P < 0.05), but not with asthma control (r = 0.18,P = 0.35). Acidity of EBC was significantly lower in asthmatic children than in healthy controls (P < 0.05), but did not correlate with any of the conventional asthma measures. We were not able to demonstrate the presence of CRP, IL‐6, IL‐8, TNF‐alpha, sICAM‐1, and sTNF‐R75 in EBC. Albumin was found in two EBC samples of asthmatic children. We conclude that exhaled NO had a better correlation with lung function parameters and asthma control than exhaled CO and acidity of EBC, in mild to moderate persistent childhood asthma. However, exhaled NO, CO, and deaerated pH of EBC did not differ between asthmatic children and controls, possibly because of a too homogeneous and well‐controlled study population. To further evaluate the clinical utility of exhaled markers in monitoring childhood asthma, more studies are required on a wider range of asthma severity, and preferably with repeated measurements of markers and of asthma control. Pediatr Pulmonol. 2004; 38:107–114. © 2004 Wiley‐Liss, Inc.
Respiratory morbidity 20 years after RSV infection in infancy
Authors: Korppi M. , Piippo‐Savolainen E. , Korhonen K. , Remes S.
Published: June 2004

Epidemiological data suggest that respiratory syncytial virus (RSV) infection in early life is a risk factor for later asthma. There are no prospective studies on RSV infection starting from infancy progressing through childhood into adulthood. We followed up a cohort of children, hospitalized for RSV bronchiolitis or RSV pneumonia before age 24 months, until age 18–20 years. The aim of the study was to evaluate early RSV infection as a risk factor for asthma, bronchial reactivity, and lung function abnormalities in young adults. The participants filled in a questionnaire on asthma and asthma‐like symptoms. The clinical study included flow‐volume spirometry (FVS), methacholine inhalation challenge (MIC), home PEF (peak expiratory flow) monitoring, and skin prick tests (SPT) to common allergens. Asthma was present in 17–22% of 36 index subjects, depending on asthma definition, compared to 11% of 45 controls. Furthermore, FEV% and MEF25 were lower, and MEF50 tended to be lower, in index than in control subjects. One or more abnormal lung function results were found in 16 (44%) index subjects, but only in 5 (11%) controls (P < 0.01). Bronchial reactivity (PD20 <4,900 μg methacholine) was demonstrated in 16 (46%) index subjects and 14 (32%) controls (NS). At least one positive SPT result was present in 21 (60%) index subjects; 6 (29%) had asthma (NS vs. nonatopic index subjects); 13 (62%) had abnormal lung function (P < 0.05); and 14 (67%) had bronchial reactivity (P < 0.01). In the logistic regression adjusted for atopy, as defined by SPT positivity, RSV infection in infancy was an independent risk factor for lung function abnormality (one or more abnormal results in FVS; OR, 5.27; 95% CI, 1.60–17.36), and also for decreased FEV% and MEF50 when these were analyzed separately. However, RSV infection in infancy was not a significant risk factor for asthma or bronchial reactivity. In young adults, lung function abnormalities may be associated with RSV infection which required hospitalization in infancy. Pediatr Pulmonol. 2004; 38:155–160. © 2004 Wiley‐Liss, Inc.
Mechanisms determining cholinergic neural responses in airways of young and mature rabbits
Authors: Larsen Gary L. , Loader Joan , Nguyen Dee Dee , Fratelli Cori , Dakhama Azzeddine , Colasurdo Giuseppe N.
Published: June 2004

Neural pathways help control airway caliber and responsiveness. Yet little is known of how neural control changes as a function of development. In rabbits, we found electrical field stimulation (EFS) of airway nerves led to more marked contractile responses in 2‐ vs. 13‐week‐old animals. This enhanced response to EFS may be due to prejunctional, junctional, and/or postjunctional neural mechanisms. We assessed these mechanisms in airways of 2‐ and 13‐week‐old rabbits. The contractile responses to methacholine did not differ in the groups, suggesting postjunctional neural events are not primarily responsible for differing responses to EFS. To address junctional events, acetylcholinesterase (AChE) was measured (spectrophotometry). AChE was elevated in 2‐week‐olds. However, this should lead to less and not greater responses. Prejunctionally, EFS‐induced acetylcholine (ACh) release was assessed by HPLC. Airways of 2‐week‐old rabbits released significantly more ACh than airways from mature rabbits. Choline acetyltransferase, a marker of cholinergic nerves, was not different between groups, suggesting that more ACh release in young rabbits was not due to increased nerve density. ACh release in the presence of polyarginine increased significantly in both groups, supporting the presence of functional muscarinic autoreceptors (M2) at both ages. Because substance P (SP) increases release of ACh, SP was measured by ELISA. This neuropeptide was significantly elevated in airways of younger rabbits. Nerve growth factor (NGF) increased SP and was also significantly increased in airways from younger rabbits. This work suggests that increases in EFS‐induced responsiveness in young rabbits are likely due to prejunctional events with enhanced release of ACh. Increases in NGF and SP early in life may contribute to this increased responsiveness. Pediatr Pulmonol. 2004; 38:97–106. © 2004 Wiley‐Liss, Inc.
Reference values for forced inspiratory flows in children aged 7–15 years
Authors: Tomalak Waldemar , Radliński Jakub , Pogorzelski Andrzej , Doniec Zbigniew
Published: June 2004

In order to construct reference equations, we attempted to measure forced inspiratory flows, i.e., peak inspiratory flow (PIF) and maximal inspiratory flow at 50% of FVC (MIF50%FVC) in 332 healthy schoolchildren aged 7–15 years during flow‐volume loop measurements, using an electronic spirometer. In 255 children (122 boys and 133 girls), the results were satisfactory. Statistical analysis revealed that the only predictive variables were sex and height. The best fit of the data was obtained with the power model (Y = A * HB); the coefficients of correlation between flows and height ranged from 0.66–0.77, and were slightly greater for boys. Forced inspiratory flows in children increase with height, and the variability is higher than for forced expiratory flows. Reference values for forced inspiratory flows can be useful in assessing the ability of children to generate affective inspiratory flows for choosing an inhalation device, or in resolving diagnostic problems, e.g., extrathoracic obstruction. © 2004 Wiley‐Liss, Inc.
Volume guarantee: Stability of tidal volume and incidence of hypocarbia
Authors: Keszler Martin , Abubakar Kabir
Published: June 2004

Excessive tidal volume (VT) can lead to lung injury, hypocarbia, and neurologic damage. Volume guarantee (VG) uses exhaled VT as the control variable to reduce the risk of volutrauma and more closely control PaCO2. Our objective was to test the hypothesis that VG combined with assist/control (A/C) will maintain PaCO2 and VT within target range more consistently than assist/control alone during the first 72 hr of life in ventilated preterm infants. Eligible infants were randomly assigned to A/C + VG or A/C alone. Data were recorded directly from the pressure and volume module of the Draeger Babylog 8000+ ventilator. Arterial blood gases were obtained every 2–6 hr, as clinically indicated. In A/C, inspiratory pressure was adjusted to achieve a VT of 4–6 ml/kg. In VG, the target VT was 5 ml/kg. Subsequent adjustments were made by the clinical team in response to arterial blood gas measurements (ABG). Proportion of breaths and PaCO2 values outside the target range were compared by χ2, and continuous variables by t‐test. There were no differences in demographic or baseline ventilator variables between the 18 infants in the two groups. For 1,805/11,950 breaths (15.1%), VT was > target with A/C + VG, vs. 2,503/9,853 (25.4%) with A/C (P < 0.001). VT was < target for 21.7% of breaths with A/C + VG, vs. 35.7% with A/C (P < 0.001). Twenty percent of PaCO2 values were < target, with A/C + VG vs. 36.3% with A/C, P < 0.05. The proportion of PaCO2 values > target was similar in the two groups. Oxygenation and mean pH were not different. No complications related to mechanical ventilation were observed. In conclusion, VG significantly reduced hypocarbia and excessively large VT. This suggests the potential to reduce pulmonary and neurologic complications of mechanical ventilation. Larger studies are needed to establish safety and demonstrate such benefits. © 2004 Wiley‐Liss, Inc.