bluuebunny/crossref_metadata_2025 huggingface dataset:
In vivo 2D mapping of impaired murine cardiac energetics in NO‐induced heart failure
Authors: Flögel Ulrich , Jacoby Christoph , Gödecke Axel , Schrader Jürgen
Published: November 2006

31P MRS studies in humans have shown that an impairment of cardiac energetics is characteristic of heart failure. Although numerous transgenic mouse models with a heart‐failure phenotype have been generated, current methods to analyze murine high‐energy phosphates (HEPs) in vivo are hampered by limited spatial resolution. Using acquisition‐weighted 2D 31P chemical shift imaging (CSI) at 9.4 Tesla, we were able to acquire 31P MR spectra over the entire thorax of the mouse with high spatial resolution in defined regions of the heart (the anterior, lateral, posterior, and septal walls) within a reasonable acquisition time of about 75 min. Analysis of a transgenic cardiomyopathy model (double mutant: cardiospecific inducible nitric oxide synthase (iNOS) overexpression and lack of myoglobin (tg‐iNOS+/myo−/−) revealed that cardiac dysfunction in the mutant was associated with an impaired energy state (phosphocreatine (PCr)/adenosine triphosphate (ATP) 1.54 ± 0.18) over the entire left ventricle (LV; wild‐type (WT): PCr/ATP 2.06 ± 0.22, N = 5, P < 0.05), indicating that in the absence of efficient cytosolic NO scavenging, iNOS‐derived NO critically interferes with the respiratory chain. In vivo data were validated against 31P MR spectra of perchloric acid extracts (PCr/ATP: 1.87 ± 0.21 (WT), 1.39 ± 0.17 (tg‐iNOS+/myo−/−, N = 5, P < 0.05). Future applications will substantially benefit studies on the cause‐and‐effect relationship between cardiac energetics and function in other genetically well‐defined models of heart failure. Magn Reson Med 57:50–58, 2007. © 2006 Wiley‐Liss, Inc.
Ultrasonography in carpal tunnel syndrome: Comparison with electrophysiological stage and motor unit number estimate
Authors: Bayrak Ilkay Koray , Bayrak Ayse Oytun , Tilki Hacer Erdem , Nural Mehmet Selim , Sunter Tevfik
Published: December 2006

The purpose of this study was to document the ultrasonographic measurement differences in median nerve size between patients with carpal tunnel syndrome (CTS) and controls, and to correlate these findings with electrophysiological stage and motor unit number estimation (MUNE), thereby allowing us to test the validity of ultrasound as a diagnostic modality for assessing the severity of CTS. High‐resolution sonography and electrophysiological studies were performed on 41 wrists of 27 patients and compared with findings on 40 wrists of 20 healthy individuals. On ultrasonographic views, cross‐sectional area and flattening ratio in proximal, middle, and distal tunnel segments of the median nerve were measured both by calculating ellipsoid area by large and small cross‐sectional diameters and by automated ellipsoid area calculation. We compared electrophysiological stage and MUNE with proximal, middle, and distal cross‐sectional area and other ultrasonographic findings. All correlations between electrophysiological stage and cross‐sectional areas in these different segments of the median nerve were significant with both measurement methods. Negative correlations were seen between MUNE and cross‐sectional area in the proximal and middle segments, whereas no significant correlation was detected in the distal segment. Our results indicate that there are close correlations between the ultrasonographic findings and electrophysiological stage. Ultrasound also reflects the reduction in the number of axons estimated by the MUNE method. Therefore, we suggest that the ultrasonographic findings reflect the severity of disease in patients with CTS. Muscle Nerve, 2006
Impaired oxygen extraction in metabolic myopathies: Detection and quantification by near‐infrared spectroscopy
Authors: Grassi Bruno , Marzorati Mauro , Lanfranconi Francesca , Ferri Alessandra , Longaretti Miriam , Stucchi Andrea , Vago Paola , Marconi Claudio , Morandi Lucia
Published: December 2006

Patients with mitochondrial myopathies (MM) or myophosphorylase deficiency (McArdle's disease, McA) show impaired capacity for O2 extraction, low maximal aerobic power, and reduced exercise tolerance. Non‐invasive tools are needed to quantify the metabolic impairment. Six patients with MM, 6 with McA, 25 with symptoms of metabolic myopathy but negative biopsy (patient‐controls, P‐CTRL) and 20 controls (CTRL) underwent an incremental cycloergometric test. Pulmonary O2 uptake (V̇O2) and vastus lateralis oxygenation indices (by near‐infrared spectroscopy, NIRS) were determined. Concentration changes of deoxygenated hemoglobin and myoglobin (Δ[deoxy(Hb + Mb)]) were considered an index of O2 extraction. Δ[deoxy(Hb + Mb)] peak (percent limb ischemia) was lower in MM (25.3 ± 12.0%) and McA (18.7 ± 7.3) than in P‐CTRL (62.4 ± 3.9) and CTRL (71.3 ± 3.9) subjects. V̇O2 peak and Δ[deoxy(Hb + Mb)] peak were linearly related (r2 = 0.83). In these patients, NIRS is a tool to detect and quantify non‐invasively the metabolic impairment, which may be useful in the follow‐up of patients and in the assessment of therapies and interventions. Muscle Nerve, 2006
Grid computing: a STOPE view
Authors: Arafah Mohammad Amer , Al‐Harbi Hazza S. , Bakry Saad Haj
Published: November 2006

Grid computing is emerging as the foundation upon which virtual organizations can be built. Such organizations are becoming of increasing importance for tackling various projects, both in academic and in business fields. This paper is concerned with presenting an integrated view of the grid to readers interested in understanding it, or perhaps in developing it further or making use of it in the future. The target view is based on the STOPE (strategy/technology/organization/people/environment) framework that has previously been used to integrate the issues of various information technology problems over its well‐defined domains. For strategy, the view considers the reasons associated with the need for the grid, including grid services and grid benefits. For technology, the technical components of the grid and their functions are taken into account. For organization, the organizations concerned with the development, technology production, service provisioning and use of the grid are considered. For people, those associated with the grid in the related organizations are taken into account. For the environment, rules, practices and support associated with the grid are discussed. Finally, the paper emphasizes questions that need to be answered in order to contribute to the future development of the grid. Copyright © 2006 John Wiley & Sons, Ltd.
Flatfoot: the palaeopathological diagnosis
Authors: Darton Y.
Published: November 2006

Bipedal human motion is related to the original shape of the foot. Distortion and degenerative changes may be caused by failure in the complex chain of movements. There are few references to valgus flatfoot in either the palaeopathological or medical literature. The study of three French medieval series (Macon, Larina and Cutry) in the osteological collections of the CEPAM (UMR 6130 – CNRS/UNSA) at Valbonne (France) enabled us to define several significant osseous signs which provide evidence of abnormal biomechanical constraints following structural change in the foot. The consequences of the change of axis of the talar pulley, abnormal osseous contacts, and evolutionary modifications noticed in some synostoses of the tarsus, are particularly useful for study. Analysis of the location of arthritic change in the joint may produce an additional coherent argument to the diagnosis. The recognition of flatfootedness in an archaeological context provides a marker of health and of distress, which is all the more interesting since bones required for this diagnosis are often present and relatively well preserved in the excavations of burials. Copyright © 2006 John Wiley & Sons, Ltd.
Disentangling the racial test score gap: Probing the evidence in a large urban school district
Authors: Stiefel Leanna , Schwartz Amy Ellen , Gould Ellen Ingrid
Published: November 2006

We examine the size and distribution of the gap in test scores across races within New York City public schools and the factors that explain these gaps. While gaps are partially explained by differences in student characteristics, such as poverty, differences in schools attended are also important. At the same time, substantial within‐school gaps remain and are only partly explained by differences in academic preparation across students from different race groups. Controlling for differences in classrooms attended explains little of the remaining gap, suggesting little role for within‐school inequities in resources. There is some evidence that school characteristics matter. Race gaps are negatively correlated with school size—implying small schools may be helpful. In addition, the trade‐off between the size and experience of the teaching staff in urban schools may carry unintended consequences for within‐school race gaps. © 2006 by the Association for Public Policy Analysis and Management.
Decentralized governance and environmental change: Local institutional moderation of deforestation in Bolivia
Authors: Andersson Krister , Gibson Clark C.
Published: November 2006

Dozens of countries have decentralized at least part of their natural resource policies over the last two decades. Despite the length of time that these policy experiments have been in force, there is little agreement about their effectiveness. We argue that part of this ambivalence stems from three limitations of extant studies, suggesting that future studies of decentralized natural resource governance should consider a combination of 1) variation in the local institutional context, 2) the fit between the reform and other public policies, and 3) more adequate outcome measures for decentralized resource governance. After developing such an approach, we posit that varying forest conditions depend on the moderating effects that local institutions have on the socioeconomic and biophysical drivers of environmental change. Analyzing data from interviews and remotely sensed images from 30 municipalities in the Bolivian lowlands, we find that the local institutional performance affects unauthorized deforestation directly and indirectly, but detect no effects on either permitted or total deforestation. © 2006 by the Association for Public Policy Analysis and Management.
Increasing the transparency of stated choice studies for policy analysis: Designing experiments to produce raw response graphs
Authors: Sur Dipika , Cook Joseph , Chatterjee Susmita , Deen Jacqueline , Whittington Dale
Published: November 2006

We believe a lack of transparency undermines both the credibility of, and interest in, stated choice studies among policy makers. Unlike articles reporting the results of contingent valuation studies, papers in the stated choice literature rarely present simple tabulations of raw response data (that is, a table or graph showing the percentage of respondents agreeing to purchase a good or service, or vote for a proposed management plan as a function of price). We describe an approach for adding “policy” tasks to a standard orthogonal‐in‐attribute‐levels research design that allows the researcher to plot raw responses as a function of changes in only one characteristic of the offered good or service. We demonstrate this approach using data from a stated choice study of private demand for cholera and typhoid vaccines in Kolkata, India, carried out in the summer of 2004. © 2006 by the Association for Public Policy Analysis and Management.
Holzer, Harry J., and Neumark, David (2006). Affirmative action: What do we know? The Journal of Policy Analysis and Management, 26(2), 463‐490.
Authors: Holzer Harry J. , Neumark David
Published: November 2006

The original article to which this Erratum refers was published in the Journal of Policy Analysis and Management 25(2), 463–490.
Proton conducting membranes based on sulfonated poly(ether ether ketone)/TiO2nanocomposites for a direct methanol fuel cell
Authors: Kalappa Prashantha , Lee Joong‐Hee
Published: December 2006

This paper presents an evaluation of the effects of titanium dioxide nanoparticles in sulfonated poly(ether ether ketone) (SPEEK) with a sulfonation degree of 57%. A series of inorganic/organic hybrid membranes was prepared with a systematic variation of titanium dioxide nanoparticle content. Their water uptake, methanol permeability and proton conductivity as a function of temperature were investigated. The results obtained show that the inorganic oxide network decreases the proton conductivity and water swelling. It is also found that increasing the inorganic oxide content leads to a decrease of methanol permeability. In terms of morphology, the membranes are homogeneous and exhibit good adhesion between inorganic domains and the polymer matrix. The proton conductivity and fuel cell performances of the nanocomposite membranes showed very good prospective in direct methanol fuel cell usages. The properties of the composite membranes are compared with those of standard Nafion membranes. Copyright © 2006 Society of Chemical Industry
Surface modification of montmorillonite and application to the preparation of polybutadiene/montmorillonite nanocomposites
Authors: Qian Xinhua , Liao Mingyi , Zhang Weiqing
Published: November 2006

Hydrophobic organic montmorillonite (OMMT) which exists as stable dispersions in cyclohexane has been prepared by the combined modification of quaternary ammonium salts and coupling agents, and polybutadiene (PB)/OMMT nanocomposites (NCs) were successfully synthesized by in situ living anionic polymerization. The results showed that the interlayer spacing of OMMT increased dramatically on increasing the length of the long alkyl chain of C12, C16, C18 and C22 in n‐alkyltrimethylammonium ions and the number of long alkyl chains of 1C16, 2C16 and 3C16 in hexadecylmethylammonium ions. The interlayer spacings reached 4.9 and 5.07 nm, respectively, when C22 and 3C16 were used. The dispersion of MMT intercalated by quaternary ammonium salts was improved significantly after surface modification by different coupling agents, and the OMMTs could be disperses stably in cyclohexane for at least 72 h. In addition, the coupling agents did not change the inherent intercalation structure of OMMT. The results from a kinetic study and 1H NMR analysis indicated that the incorporation of OMMT had little influence on the living polymerization and PB microstructure (proportions of 1,2‐ and 1,4‐units) when the OMMT content was below 3 wt%. However, the OMMT modified by different coupling agents had some influence on the molecular weight distribution. The results from transmission electron microscopy and X‐ray diffraction revealed that exfoliated structures of clay were obtained for all NCs. Furthermore, the results of differential scanning calorimetry and thermogravimetric analysis indicated that Tg and Tdc of NCs were increased compared to those of PB. Copyright © 2006 Society of Chemical Industry
Surface enrichment and crystallization of polyamide and polytetrafluoroethylene blend
Authors: Song Rui , Yang Debin , He Linghao , Yao Guangtao
Published: November 2006

The blend surface of polyamide 6 and polytetrafluoroethylene (PA 6/PTFE) and its change as a function of annealing time are investigated by means of attenuated total reflection (ATR)‐FTIR spectroscopy, contact angle (CA) measurement, as well as atomic force microscopy (AFM) under ambient condition; meanwhile the surface elemental compositions are obtained by X‐ray photoelectron spectroscopy (XPS). The results show that the addition of fluoro content can decrease the surface energy compared with the pure polyamide, while, an evident influence on the surface energy has not been detected with increasing fluoro contents. Upon annealing at 120 °C, there is a profound enrichment of the low‐surface energy component to the sample surface; yet this situation becomes more complex when samples are annealed at 150 °C—not only the segregation effect from the low surface energy PTFE, but also the crystallization of the PA 6 will come into play for the blend with 50% PTFE. These observations are ascribed to the presence of the polar group of the polyamide component, as well as its strong tendency to crystallize when subjected to thermal treatment at sufficiently high temperatures, and this behavior would basically offset the segregation tendency of fluoro component to the sample surface. This assumption is further corroborated by the XPS measurement in the current researches. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 138–152, 2007
Development of morphology and properties of injection‐molded bars of HDPE/PA6 blends along flow direction
Authors: Li Jiang , Yu Xiaofeng , Guo Shaoyun
Published: December 2006

The structure and mechanical properties of injection‐molded bars of high‐density polyethylene (HDPE)/PA6 blends were studied in this article. The experimental results showed that the morphologies of injection‐molded bars change gradually along the flow direction, which is tightly related to the melt viscosity and processing conditions. The higher melt viscosity, lower mold temperature, and shorter packing time, restricting the macromolecular relaxation, enhance the difference in morphologies and properties at near and far parts of a mold. An injection‐molded bar (namely H2C5), consisting of 75 wt % of HDPE, 20 wt % of PA6, and 5 wt % of compatibilizer (HDPE‐g‐MAH), showed a greater difference in mechanical properties at near and far parts because of its higher melt viscosity. A clear interface between the skin and core layers of near part in it leads to a much higher impact strength than that of far part. And tensile tests show that its tensile strength of near part is higher than that of far part due to the higher orientation degrees of HDPE matrix and PA6 dispersed phase in near part. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 184–195, 2007
Side‐chain crystallization behavior of graft copolymers consisting of an amorphous main chain and crystalline side chains. II. Poly(n‐hexyl methacrylate)‐graft‐poly(ethylene glycol)
Authors: Inomata Katsuhiro , Fukuda Chieko , Hori Kuniyoshi , Sugimoto Hideki , Nakanishi Eiji
Published: November 2006

The phase behavior and crystallization of graft copolymers consisting of poly(n‐hexyl methacrylate) (PHMA) as an amorphous main chain and poly(ethylene glycol) (PEG) as crystallizable side chains (HMAxwith 15 ≤x≤ 73, wherexrepresents the weight percentage of PEG) were investigated. Small‐angle X‐ray scattering profiles measured above the melting temperature of PEG suggested that a microdomain structure with segregated PHMA and PEG domains was formed in HMA40 and HMA46. This phase behavior was qualitatively described by a calculated phase diagram based on the mean‐field theory. Because of the segregation of PEG into microdomains, the crystallization temperature of the PEG side chains in HMAxwas higher than that in poly(methyl acrylate)‐graft‐poly(ethylene glycol) having a similar value ofx, which was considered to be in a disordered state above the melting temperature. In HMAxwithx≤ 40, PEG crystallization was strongly restricted, probably because the PEG microdomains were isolated in the PHMA matrix. As a result, the growth of PEG spherulite was not observed because the PEG crystallization occurred after vitrification of the PHMA segregated domains. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 129–137, 2007
Prostate cells express two isoforms of fibroblast growth factor receptor 1 with different affinities for fibroblast growth factor‐2
Authors: Roghani Monireh , Moscatelli David
Published: December 2006

Background

Fibroblast growth factor receptor 1 (FGFR1) mRNA can be alternatively spliced to generate isoforms containing (FGFR1α) or lacking (FGFR1β) the first immunoglobulin‐like domain. We examined which isoforms are expressed by cultured prostate cells, their affinities for FGF‐2, and the effect of heparin on FGF‐2 binding.

Methods

FGFR1 isoform expression was examined by RT‐PCR. FGFR1α and FGFR1β were expressed in CHO cells mutant in heparan sulfate synthesis, and their affinities for FGF‐2, FGF‐1, FGF‐4, and FGF‐6 were determined in the presence and absence of heparin.

Results

FGFR1α was expressed in luminal epithelial cells, whereas FGFR1β was expressed in basal epithelial and smooth muscle cells. FGFR1β bound FGF‐2 with three–fourfold higher affinity than FGFR1α both in the presence and absence of heparin. Heparin increased affinity of both receptor isoforms for FGF‐2 approximately four–fivefold.

Conclusions

Prostate smooth muscle and basal epithelial cells are likely to be more sensitive than luminal epithelial cells to the low concentrations of FGFs present in vivo. Prostate © 2006 Wiley‐Liss, Inc.
Structural insights into the GTPase domain of Escherichia coli MnmE protein
Authors: Monleón Daniel , Martínez‐Vicente Marta , Esteve Vicent , Yim Lucia , Prado Silvia , Armengod Maria‐Eugenia , Celda Bernardo
Published: December 2006

The Escherichia coli MnmE protein is a 50‐kDa multidomain GTPase involved in tRNA modification. Its homologues in eukaryotes are crucial for mitochondrial respiration and, thus, it is thought that the human protein might be involved in mitochondrial diseases. Unlike Ras, MnmE shows a high intrinsic GTPase activity and requires effective GTP hydrolysis, and not simply GTP binding, to be functionally active. The isolated MnmE G‐domain (165 residues) conserves the GTPase activity of the entire protein, suggesting that it contains the catalytic residues for GTP hydrolysis. To explore the GTP hydrolysis mechanism of MnmE, we analyzed the effect of low pH on binding and hydrolysis of GTP, as well as on the formation of a MnmE transition state mimic. GTP hydrolysis by MnmE, but not GTP binding or formation of a complex with mant‐GDP and aluminium fluoride, is impaired at acidic pH, suggesting that the chemistry of the transition state mimic is different to that of the true transition state, and that some residue(s), critical for GTP hydrolysis, is severely affected by low pH. We use a nuclear magnetic resonance (NMR)‐based approach to get insights into the MnmE structure and properties. The combined use of NMR restraints and homology structural information allowed the determination of the MnmE G‐domain structure in its free form. Chemical shift structure‐based prediction provided a good basis for structure refinement and validation. Our data support that MnmE, unlike other GTPases, does not use an arginine finger to drive catalysis, although Arg252 may play a role in stabilization of the transition state. Proteins 2007. © 2006 Wiley‐Liss, Inc.
Thermoelectric properties and phase transitions of II–VI semiconductors at high pressure
Authors: Shchennikov Vladimir V. , Ovsyannikov Sergey V.
Published: December 2006

The high‐pressure phase transitions in II–VI semiconductors (HgTe, HgSe, HgS, HgO, CdTe, CdSe, CdS, ZnTe, ZnSe, ZnS, ZnO) are analyzed in light of recent findings. A contribution is emphasized of the thermoelectric power (Seebeck effect) technique to registration of new electronic phases and to prediction of their related structural modifications. A novel thermopower study of ZnX (X–Te, Se, S) revealed a difference between the high‐pressure NaCl phases of ZnSe and ZnS and the orthorhombic Cmcm phase of ZnTe. Mechanisms of the pressure‐induced transitions in ZnX and other II–VI compounds are discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Non‐parametric bounds on treatment effects with non‐compliance by covariate adjustment
Authors: Cai Zhihong , Kuroki Manabu , Sato Tosiya
Published: November 2006

Consider a clinical trial where subjects are randomized to two treatment arms but compliance to the assignment is not perfect. Concerning this problem, this paper derives non‐parametric bounds on treatment effects by making use of the observed covariates information. The new bounds are narrower and more informative than the existing ones. In addition, a new non‐parametric point estimation approach is proposed based on stratified analysis. Furthermore, to examine the accuracy of estimating the proposed bounds, we provide variance estimators for the proposed approach. The results of this paper can yield credible information on treatment effects, which will be useful for medical research and public health policy analysis. Copyright © 2006 John Wiley & Sons, Ltd.
A Thai community's anniversary reaction to a major catastrophe
Authors: Assanangkornchai Sawitri , Tangboonngam Sa‐nguansri , Sam‐angsri Nisan , Edwards J. Guy
Published: December 2006

The aim of this study was to investigate changes in the prevalence of adverse stress reactions in different areas of Hat Yai during the year immediately following a major natural disaster—the flood of 2000. Samples of around l00 residents of each of four areas exposed to different degrees of severity of the stressors caused by the flood were followed‐up at 8 to l0 week intervals. When first interviewed on entry into the study, the respondents were invited to complete a structured questionnaire that sought information on their personal characteristics, data on the various flood‐related stressors to which they were exposed, and their responses to these stressors. They also completed a Thai version of the 12‐item General Health Questionnaire and the Impact of Events Scale at each of the five data collection times. There was a gradual decline in the scores on these instruments over the l2 month period but, on the anniversary of the flood, there was an increase in scores among residents confined to those areas of Hat Yai where the risk and/or consequences of severe flooding was highest and where rescue work was most difficult. This is considered to be the first epidemiological study of a major civilian disaster that has demonstrated an increase in prevalence of stress‐related symptoms as an anniversary reaction within a community. Copyright © 2006 John Wiley & Sons, Ltd.
The factorial validity and measurement invariance of the Maslach Burnout Inventory for human services
Authors: Vanheule Stijn , Rosseel Yves , Vlerick Peter
Published: December 2006

This paper first examines the factorial validity of the Maslach Burnout Inventory for human services professions (MBI‐HSS). The authors test the original 22‐item version and a shortened 20‐item version. Model fit is evaluated with confirmatory factor analysis starting with data collected from a sample of hospital nurses (n = 2515) and a sample of nurses and assistants working in residential welfare institutions (n = 1639). Only the fit of the 20‐item MBI‐HSS was good in both samples. Next the hypothesis of measurement invariance of the 20‐item MBI‐HSS across the samples is examined, but this hypothesis does not hold. Partial invariance at the level of the subscales also could not be confirmed. The authors conclude that for hospital nurses the MBI‐HSS factors mean something other than what they mean for professionals working in welfare institutions, and suggest that future research could focus upon this difference. Copyright © 2006 John Wiley & Sons, Ltd.
Physical Aging of Amorphous Starches (A Review)
Authors: Chung Hyun‐Jung , Lim Seung‐Taik
Published: November 2006

In recent years, physical behaviors of glassy foods are greatly focused as many processed foods are consumed in their glassy states. Physical aging is one of the important phenomena for glassy foods, which is responsible for quality changes vs. retention of freshness during storage. The aging phenomenon can be predicted on the basis of a process of thermodynamic relaxation, induced by structural rearrangements in amorphous matrices. Thus, it can be evaluated by using calorimetric, volumetric, and mechanical analyses. Starch is one of the principal components in most cereal‐based glassy foods, and its aging is thus relevant to the overall changes in quality and freshness of various cereal‐based food products. The polymeric theory for the physical aging of glassy starch is reviewed on the basis of the existing literature, and the aging kinetics based on the changes in various physical and thermal properties are discussed.
A study of the effect of sustained, whole‐school professional development on student achievement in science
Authors: Johnson Carla C. , Kahle Jane Butler , Fargo Jamison D.
Published: December 2006

This longitudinal study of middle school science teachers explored the relationship, if any, between teacher participation in whole‐school, sustained, collaborative professional development and student achievement in science. Eleven teachers from Glendale Middle School participated in the Discovery Model Schools Initiative 2‐week summer institute, followed by monthly release day professional development sessions focused on implementing instruction outlined in the National Science Education Standards. Student achievement was assessed using the Discovery Inquiry Test in Science. The same students completed the test in grades 6–8. Students of teachers at Glendale Middle School significantly outperformed students at the control school. Findings in this study revealed the positive impact that whole‐school, sustained, collaborative professional development programs have on student achievement, indicating that programs of this nature could be a means to narrowing or eliminating achievement gaps in science. © 2006 Wiley Periodicals, Inc. J Res Sci Teach 44: 775–786, 2007
Verbessertes Kaltkathoden‐Ionisationsmanometer mit verlängerter Lebensdauer
Authors: Wilfert Stefan , Edelmann Christian
Published: November 2006

Wird ein Kaltkathoden‐Ionisationsmanometer in einer kohlenwasserstoffhaltigen Gasatmosphäre bei hohen Drücken im Vakuumbereich betrieben, dann wird die mittlere Lebensdauer des Manometers durch eine Kontamination der Elektroden und damit durch eine starke Veränderung der Entladungsstrom‐Druck‐Kennlinie begrenzt. Infolgedessen liefert das Messgerät nach einer gewissen Betriebszeit entweder keine verlässliche Druckanzeige mehr oder kann im ungünstigsten Fall ganz ausfallen. Im Folgendem wird ein verbessertes Kaltkathoden‐Ionisationsvakuummeter vom inversen Magnetron‐Typ vorgestellt, welches speziell für den Langzeitbetrieb in stark kohlenwasserstoffhaltigen Restgasatmosphären konzipiert wurde. Der Messkopf weist bei annähernd konstanter Messgenauigkeit eine mindestens 3‐fach höhere Lebensdauer als kommerziell erhältliche Kaltkathoden‐Messröhren auf. Erreicht wurde dies durch die Verwendung zweier getrennter Entladungskammern in einem gemeinsamen Messröhrengehäuse, wobei die am Röhreneingang positionierte Entladungszone lediglich als Ionenbaffle wirkt und die weiter innen liegende Entladung als Messgrundlage fungiert. Es werden der Prototyp des entwickelten kontaminationsarmen inversen Doppelmagnetrons vorgestellt und Untersuchungsergebnisse zum Langzeitmessverhalten präsentiert.
Gießformherstellung durch Beschichtung von Modellen
Authors: Schebesta Thomas , Heikenwälder Jürgen , Zimmer Otmar
Published: November 2006

Es wird eine neuartige Werkzeug‐ und Formenbautechnologie zur kostengünstigen Herstellung standzeitoptimierter Formwerkzeuge vorgestellt. Mit dieser Technologie ist die wirtschaftliche Fertigung von Prototypen und Kleinserien auch im schwer verarbeitbaren Serienwerkstoff möglich.

Das entwickelte innovative Herstellverfahren für Gießformen und Spritzgießwerkzeuge basiert auf der Abformung eines Positivmodells durch Schichtverbunde. Diese, die Geometrie des Modells speichernden, grenzflächenoptimierten Schichtverbunde bilden mit einer Hinterfütterung nach Entfernen des Teiles und dem Anbringen der gießtechnischen Einrichtung die Werkzeugstammform. Der Aufbau der Schichtverbunde erfolgt mit aktivierten Bogenbeschichtungsverfahren (PVD‐Verfahren) für die die spätere Werkzeugoberfläche bildende Funktionsschicht und durch Plasmaspritzbeschichten (APS) für die Stützschicht.

Mit einem derart hergestellten Spritzgießwerkzeug können mehr als 1000 Teile eines mit Glasfasern verstärkten Kunststoffes oder mehr als 1500 Teile eines unverstärkten Kunststoffes in hoher Qualität gefertigt werden.
Intelligente Schichten für „denkende Oberflächen”︁
Authors: Bräuer Günter , Bandorf Ralf , Biehl Saskia , Dietz Andreas , Lüthje Holger , Vergöhel Michael
Published: November 2006

Die Herstellung intelligenter Oberflächen nach dem Vorbild der Natur ist ein wichtiges Forschungsthema der nahen Zukunft. Bereits heute gibt es Beispiele für Beschichtungen, die in der Lage sind, entweder intrinsisch oder von außen gezielt gesteuert ihre Eigenschaften an Umweltbedingungen anzupassen. Dazu gehören z. B. Sonnenschutzbeschichtungen mit schaltbarer Transmission oder selbstreinigende Oberflächen auf der der Basis der Photokatalyse.

Neuartige Schichten mit hervorragenden tribologischen Eigenschaften und sensorischen Fähigkeiten eröffnen neue Wege in der zukünftigen Gestaltung von Antriebselementen. Sie besitzen das Potential, den aktuellen Zustand einer mechanisch belasteten Oberfläche jederzeit kontrollieren und in geeigneter Weise beeinflussen zu können. Beispiele dafür sind piezoresistive amorphe Kohlenstoffschichten, die ausgeprägte kraftsensorische Eigenschaften bei gleichzeitig hoher Härte und niedrigen Reibungskoeffizienten besitzen. Die Einsatzmöglichkeiten solcher Dünnschichtsensoren sind außerordentlich vielfältig.
Cytostatic activity of syntheticO‐alkylglycerolipids
Authors: Brachwitz Hans , Langen Peter , Arndt Dieter , Fichtner Iduna
Published: December 2006

A series of halogen‐containing alkylglycerolipid analogs has been checked for their cytostatic activity both in vitro and in vivo. The compounds included alkyldeoxyhaloglycerols (I), alkyldeoxyhaloglycerophosphocholines (II), and alkyldeoxyhaloglycerophosphoric acids and alkyl esters (III). While compounds I and III were moderately active, compounds II were found to have a strong inhibitory effect on the proliferation of Ehrlich ascites tumor cells in vitro. Cell growth inhibition of 50% or more was found mainly in the late S‐ or G2‐phase of the cell cycle as revealed by flow cytometry. Alkyl lysophospholipid analogs II and cholesterol form liposomes with high encapsulation efficiency and low permeability for entrapped substances. Compounds II were active against Lewis lung carcinoma in mice when applied in free form or as liposomes.
Distribution and metabolism of hexadecylphosphocholine in mice
Authors: Breiser A. , Kim D. ‐J. , Fleer E. A. M. , Damenz W. , Drube A. , Berger M. , Nagel G. A. , Eibl H. , Unger C.
Published: December 2006

Distribution and metabolic fate of radiolabeled hexadecylphosphocholine (He‐PC) has been studied in mice. It is demonstrated that He‐PC is well‐absorbed from the intestinal tract, intravenous (IV) and oral administration lead to similar distributions throughout the body, the highest accumulation of radioactivity occurs in liver, lung and kidney, and the metabolic products are radioactive choline, phosphocholine and 1,2‐diacylphosphatidylcholine. The occurrence of these metabolites indicates that phospholipases C and D may be involved in He‐PC breakdown.
Alkyl phosphocholines: Toxicity and anticancer properties
Authors: Muschiol C. , Berger M. R. , Schuler B. , Scherf H. R. , Garzon F. T. , Zeller W. J. , Unger C. , Eibl H. J. , Schmähl D.
Published: December 2006

The study reports on the investigation of acute and subacute toxicity and on antineoplastic activity of hexadecylphosphocholine (HPC), the first compound of a new class of antineoplastic chemotherapeutics. In rats, the LD50 of HPC was 606 μmol/kg; the maximum tolerable dose over four weeks was 39 μmol/kg. Symptoms of toxicity were enteritis, spider cell activation in the liver, hemosiderosis in the spleen and reversible transaminase increase. The best therapeutic effect was observed on methylnitrosourea (MNU)‐induced mammary carcinoma in the rat. Two transplantable mammary carcinomas in the rat and autochthonous benzo(a)pyrene‐induced sarcomas exhibited low‐grade sensitivity to HPC. The MXT mammary carcinoma of the mouse, the Walker 256 carcinosarcoma of the rat, and autochthonous acetoxymethylmethylnitrosamine‐induced colonic tumors of the rat were not chemosensitive to HPC.
Modulation of chemical carcinogenesis in rats by alkyl lysophospholipids
Authors: Berger Martin R. , Schmähl Dietrich
Published: December 2006

The influence of 1‐O‐octadecyl‐2‐O‐methyl‐rac‐glycero‐3‐phosphocholine (ET‐18‐OCH3) and 1‐hexadecylmercapto‐2‐methoxymethyl‐rac‐propyl‐3‐phosphocholine (TLP, BM41.440) on methylnitrosourea (MNU)‐induced rat mammary carcinomas and of ET‐18‐OCH3 on 7,12‐dimethylbenzanthracene (DMBA)‐induced leukemias was investigated. Both agents effectively delayed MNU‐induced mammary tumor formation at high, cytotoxic dosages but TLP had no influence at low “immunomodulatory” doses. ET‐18‐OCH3 also significantly protected against leukemia development in DMBA‐treated Long‐Evans rats.
In vitro and in vivo cytotoxicity of alkyl lysophospholipid ET‐18‐OCH3 and thioether lipid BM 41.440
Authors: Leder G. H. , Fiebig H. H. , Wallbrecher E. , Winterhalter B. R. , Löhr G. W.
Published: December 2006

Screening for cytotoxicity in the clonogenic assay in human tumor xenografts and L1210 mouse leukemia revealed comparable dose‐dependent effects of the alkyl lysophospholipid ET‐18‐OCH3 and the thioether lipid BM 41.440. The efficacy in human tumors only was marginal at low doses. In vivo tests of both agents were carried out in nude mice bearing two of the tumors that proved most sensitive in vitro and in mice inoculated with L1210 leukemia. Only small effects on the growth of the human tumors and no effects on L1210 leukemia were observed. In view of clinical rules for definition of remission, no convincing antitumor effects were obtained.
Late presentation of medium‐chain acyl‐CoA dehydrogenase deficiency
Authors: Mayell S. J. , Edwards L. , Reynolds F. E. , Chakrapani A. B.
Published: December 2006

Medium‐chain acyl‐CoA dehydrogenase (MCAD) deficiency is the commonest disorder of fatty acid metabolism, with a high incidence of morbidity and mortality at presentation. We report a 16 year old girl with first presentation of MCAD deficiency following an alcoholic binge and subsequent period of starvation. Presentation was as acute encephalopathy progressing to coma. Renal, cardiac and hepatic failures were managed with intensive supportive care including mechanical ventilation, inotropic support, blood products and renal replacement therapy. Diagnosis of MCAD deficiency was confirmed on day 6. The patient was discharged from hospital on day 20 with a mild proximal myopathy, which subsequently resolved. The diagnosis of MCAD deficiency requires a high index of suspicion at all ages. Precipitating factors in later life may include alcohol.
Serum‐free mouse embryo cells generate a self‐sustaining feedback loop for an astrocyte marker protein and respond to cytokines and bisphenol A in accordance with the subtle difference in their differentiation state
Authors: Yamaguchi Hideaki , Zhu Jun , Yu Tao , Sasaki Kazuo , Umetsu Hironori , Kidachi Yumi , Ryoyama Kazuo
Published: November 2006

Serum‐free mouse embryo (SFME) cells, the astrocyte progenitor cells in the central nervous system, generated a self‐sustaining feedback loop for glial fibrillary acidic protein (GFAP) expression after a period of cell passages. The period required was about 150 days (30 passages). SFME and high‐GFAP‐expressing SFME (G‐SFME) cells were exposed to 10 ng/ml leukemia inhibitory factor (LIF) and 10 ng/ml bone morphogenetic protein 2 (BMP2) to induce differentiation and their responses to cytokine signals were analyzed. Although differentiation was significantly induced in both cell types, SFME cells showed more obvious responses to the cytokine signals. Various concentrations of bisphenol A (BPA) (0.1 pg/ml to 1 μg/ml) were added to determine its effects on cell differentiation. A completely serum‐free culture was developed for effective differentiation of G‐SFME cells with LIF and BMP2, and GFAP expression was significantly increased in the presence of 1–100 pg/ml BPA. These increases were attributed to excessive activation of signal transducer and activator of transcription 3 (STAT3) and mothers against decapentaplegic homolog 1 (Smad1) by the low‐level BPA. The data obtained in the present study revealed that the sensitivity of the cells to LIF, BMP2 and BPA could change upon cell differentiation, suggesting that the cells may possibly respond differently to cytokines and endocrine disruptors depending on subtle differences in their differentiation state.
Residual stress ischaemia is associated with blood markers of myocardial structural remodelling
Authors: Radauceanu Anca , Moulin Frédéric , Djaballah Wassila , Marie Pierre Y. , Alla François , Dousset Brigitte , Virion Jean M. , Capiaumont Josette , Karcher Gilles , Aliot Etienne , Zannad Façez
Published: November 2006

Background:

Long‐term prognosis of coronary artery disease (CAD) patients is worsened when stress ischemia persists on treatment, but the relationship with adverse cardiac remodelling had never been investigated.

Aim:

To analyze changes in blood markers of fibrosis in patients with chronic CAD exhibiting exercise ischaemia.

Methods:

Circulating markers of collagen: (i) turnover (amino‐terminal propeptide of collagen‐III [PIIINP]) and (ii) degradation (matrix metalloproteinase 1 [MMP‐1]), were obtained in 139 CAD patients referred for exercise 201Tl‐SPECT.

Results:

In the 57 patients who had SPECT‐ischaemia, PIIINP was higher (4.3±2.9 μg L−1 vs. 3.1±1.5 μg L−1, p=0.002) and MMP‐1 lower (3.8±2.1 μg L−1 vs. 4.7±2.8 μg L−1, p=0.04) than in the 82 patients without SPECT‐ischaemia. PIIINP was independently related to LV volume, SPECT‐ischaemia and age, whereas MMP‐1 was related to current treatment with ACEI and β‐blockers (p<0.05).

In the 104 patients with a normal LV ejection fraction, only PIIINP was related to SPECT‐ischaemia (4.1±2.2 μg L−1 vs. 3.1±1.5 μg L−1, p=0.01).

Conclusion:

In patients with chronic CAD, exercise ischaemia is associated with increased collagen‐III turnover, independently of concomitant medications and even when LV ejection fraction is normal. Long‐term, this increase might relate to adverse cardiac remodelling even when cardiac function is not clearly affected at baseline.
Effect of religion on suicide attempts in outpatients with schizophrenia or schizo-affective disorders compared with inpatients with non-psychotic disorders
Authors: Huguelet Philippe , Mohr Sylvia , Jung Valérie , Gillieron Christiane , Brandt Pierre-Yves , Borras Laurence
Published: December 2006

Little is known of the relations between psychosis, religion and suicide. One hundred and fifteen outpatients with schizophrenia or schizo-affective disorder and 30 inpatients without psychotic symptoms were studied using a semi-structured interview assessing religiousness/spirituality. Their past suicide attempts were examined. Additionally, they were asked about the role (protective or incentive) of religion in their decision to commit suicide. Forty-three percent of the patients with psychosis had previously attempted suicide. Religiousness was not associated with the rate of patients who attempted suicide. Twenty-five percent of all subjects acknowledged a protective role of religion, mostly through ethical condemnation of suicide and religious coping. One out of ten patients reported an incentive role of religion, not only due to negatively connotated issues but also to the hope for something better after death. There were no differences between groups (i.e. psychotic vs. non-psychotic patients). Religion may play a specific role in the decisions patients make about suicide, both in psychotic and non-psychotic patients. This role may be protective, a finding particularly important for patients with psychosis who are known to be at high risk of severe suicide attempts. Interventions aiming to lower the number of suicide attempts in patients with schizophrenia should take these data into account.
Endogenous 15‐deoxy‐Δ12,14‐prostaglandin J2 synthesized by adipocytes during maturation phase contributes to upregulation of fat storage
Authors: Mazid Md. Abdul , Chowdhury Abu Asad , Nagao Kohjiro , Nishimura Kohji , Jisaka Mitsuo , Nagaya Tsutomu , Yokota Kazushige
Published: November 2006

15‐Deoxy‐Δ12,14‐prostaglandin J2 (15d‐PGJ2) has been identified as a natural ligand for peroxisome proliferator‐activated receptor (PPAR) γ to promote adipogenesis. However, it remains elusive about the ability of PPARγ‐expressing adipocytes to produce PGJ2 series and the role in the life cycle of adipocytes. Here, we developed an enzyme‐linked immunosorbent assay specific for 15d‐PGJ2. The analysis using this method revealed the increase in the endogenous synthesis of immunoreactive 15d‐PGJ2 in cultured adipocytes during the maturation phase. Further studies using cyclooxygenase inhibitors clarified the contribution of endogeous 15d‐PGJ2 produced by mature adipocytes to upregulation of fat storage in an autocrine manner.
YCA1 participates in the acetic acid induced yeast programmed cell death also in a manner unrelated to its caspase‐like activity
Authors: Guaragnella Nicoletta , Pereira Clara , Sousa Maria João , Antonacci Lucia , Passarella Salvatore , Côrte-Real Manuela , Marra Ersilia , Giannattasio Sergio
Published: November 2006

Yeast cells lacking the metacaspase‐encoding gene YCA1 (Δyca1) were compared with wild‐type (WT) cells with respect to the occurrence, nature and time course of acetic‐acid triggered death. We show that Δyca1 cells undergo programmed cell death (PCD) with a rate lower than that of the WT and that PCD in WT cells is caused at least in part by the caspase activity of Yca1p. Since in Δyca1 cells this effect is lost, but z‐VAD‐fmk does not prevent both WT and Δyca1 cell death, PCD in WT cells occurs via a Yca1p caspase and a non‐caspase route with similar characteristics.
Reproductive biology of Atlantoraja cyclophora (Regan 1903) (Elasmobranchii: Rajidae) off southern Brazil
Authors: Oddone María Cristina , Vooren Carolus Maria
Published: December 2006

A total of 459 (245 females, 214 males) Atlantoraja cyclophora was captured by bottom trawl off the coast of Rio Grande do Sul between 30°40′S and 34°30′S during surveys conducted in winter 2001 and summer/autumn 2002 at depths of 100–300 m. Total length at maturity was 52.8 cm for females and 48.5 cm for males. Symmetry and functional parity of the gonads were observed in both sexes, but there was no significant temporal variation in either sex for any of the reproductive parameters studied. Ovulation and egg-deposition were similarly intensive in both seasons. In adult females, there was an ovarian resting period at an individual level, though it was not synchronized at a population level. Distribution of egg-bearing females was not related to depth or species' range.
Application of mitomycin‐C for head and neck keloids
Authors: Stewart Charles E. , Kim John Y.
Published: November 2006

Keloids of the head and neck are a relatively common entity in darker‐skinned races, occurring in 5%‐15% of skin wounds. Keloids are fibrotic lesions that are a result of an abnormal wound‐healing process that lacks control of the mechanisms that regulate tissue repair and regeneration. The proliferation of normal tissue‐healing processes results in scarring that enlarges well beyond the original wound margins.

Many treatment modalities for keloids have been tried with variable amounts of success. Surgical excision, compressive therapy, silicon dressings, corticosteroid injections, radiation, cryotherapy, interferon therapy, and laser therapy have all been used alone or in combination. Despite this wide range of available treatments, recurrence rates typically remain in the 50%‐70% range.

In this study, we present our results in a series of 10 patients who were treated with surgical excision of head and neck keloids and the application of topical mitomycin‐C. Mitomycin‐C is a chemotherapeutic agent that inhibits DNA synthesis and fibroblast proliferation. It has been used in ophthalmologic procedures and airway surgery to decrease scar formation. In these 10 patients, we combined surgical excision of keloids with the application of topical mitomycin‐C. The patients were then followed postoperatively for recurrence (range, 7‐14 months). We have found topical application of mitomycin‐C to be an effective therapy for prevention of keloid recurrence in the head and neck, with a success rate of 90% as reported in this series.