bluuebunny/crossref_metadata_2025 huggingface dataset:
Elevated mean diffusivity in widespread brain regions in congenital central hypoventilation syndrome
Authors: Kumar Rajesh , Macey Paul M. , Woo Mary A. , Alger Jeffry R. , Harper Ronald M.
Published: October 2006

Purpose

To investigate whether mean diffusivity (MD) values are altered in brain areas underlying cardiovascular and respiratory control in congenital central hypoventilation syndrome (CCHS).

Materials and Methods

Conventional and diffusion tensor imaging were performed in 15 CCHS and 30 control subjects, using a 3.0‐Tesla MRI unit. Mean diffusivity maps were calculated from diffusion‐weighted images, spatially normalized, smoothed, and compared between groups using analysis of covariance at each voxel with age as covariate. Global mean MD values of gray and white matter were determined in individual subjects and compared between groups and with age.

Results

Increased MD values appeared in CCHS over control subjects within multiple areas influencing breathing and cardiovascular control, including the midbrain, pons, and dorsal and ventral medulla. Other altered sites included cerebellar cortex and deep nuclei, basal ganglia, basal forebrain, and temporal and frontal cortices. Global mean MD values for gray and white matter did not differ between groups; however, gray matter MD values significantly increased with age (P < 0.02) in CCHS patients only.

Conclusion

Increased MD values suggest regional alterations or injury; affected areas include brainstem sites classically associated with autonomic and respiratory control. Other altered regions mediate additional physiological characteristics impaired in CCHS. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Involvement of prostaglandin E2released from leptomeningeal cells in increased expression of transforming growth factor‐β in glial cells and cortical neurons during systemic inflammation
Authors: Wu Zhou , Hayashi Yoshinori , Zhang Jian , Nakanishi Hiroshi
Published: October 2006

The leptomeninges play a central role in the antiinflammatory response through the glia–neuron interaction during systemic inflammation. In the present study, we examined the possible production of two potent antiinflammatory mediators, prostaglandin E2(PGE2) and transforming growth factor‐β1 (TGF‐β1) by leptomeningeal cells during systemic inflammation. After immunization with the complete Freund's adjuvant (CFA), cyclooxygenase (COX)‐2 and membrane‐bound PGE synthase‐1 (mPGES‐1) were induced in the leptomeninges. Primary cultured leptomeningeal cells secreted PGE2after treatment with lipopolysaccharide (LPS) or proinflammatory cytokines. The LPS‐induced release of PGE2was depressed by a selective COX‐2 inhibitor, NS‐398. On the other hand, TGF‐β1 and TGF‐β receptor II (TGF‐βRII) both markedly increased in the leptomeninges and the parenchymal cells after the CFA injection. Double‐staining immunohistochemistry demonstrated TGF‐β1 to be induced in both glial cells and cortical neurons, whereas TGF‐βRII was induced only in cortical neurons. Furthermore, the conditioned medium prepared from the leptomeningeal cells after LPS stimulation was able to induce an increased expression of TGF‐β1 and TGF‐βRII in the primary cultured glial cells and cortical neurons. This increased expression was suppressed by NS‐398. PGE2was found to increase directly the production of TGF‐β1 and TGF‐βRII in the primary cultured cells. These observations strongly suggest that PGE2, which is biosynthesized by the leptomeninges, mainly regulates the production of TGF‐β1 by glial cells and cortical neuron, thus playing a protective role in the cortical neurons during systemic inflammation. Furthermore, TGF‐β1 may also exert a protective effect directly on the cortical neurons. © 2006 Wiley‐Liss, Inc.
Rho kinase activates ezrin‐radixin‐moesin (ERM) proteins and mediates their function in cortical neuron growth, morphology and motility in vitro
Authors: Haas Matilda A. , Vickers James C. , Dickson Tracey C.
Published: October 2006

The ezrin‐radixin‐moesin (ERM) family of proteins contribute to cytoskeletal processes underlying many vital cellular functions. Their previously elucidated roles in non‐neuronal cells are an indication of their potential importance in CNS neurons. The specific mechanisms of their activation are unknown, but are likely to depend on factors such as the cell type and biological context. For ERM proteins to become active they must be phosphorylated at a specific C‐terminal threonine residue. In non‐neuronal cells, several kinases, including the Rho GTPase family member Rho kinase, have been identified as capable of phosphorylating the C‐terminal threonine. In these experiments we have investigated specifically the potential role of Rho kinase mediated ERM activation in cortical neurons, utilizing a new pharmacologic inhibitor of Rho kinase and quantitative analysis of aspects of neuronal functions potentially mediated by ERM proteins. Rho kinase inhibition significantly suppressed aspects of neuronal development including neurite initiation and outgrowth, as well as growth cone morphology, with a concomitant loss of phosphorylated ERM immunolabeling in areas associated with neuronal growth. The ability of the Rho kinase inhibitor to decrease the amount of pERM protein was shown by immunoblotting. Post‐injury responses were negatively affected by Rho kinase inhibition, namely by a significant decrease in the number of regenerative neurites. We investigated a novel role for ERM proteins in neuron migration using a post‐injury motility assay, where Rho kinase inhibition resulted in significant and drastic reduction in neuron motility and phosphorylated ERM immunolabeling. Thus, Rho kinase is an important activator of ERMs in mediating specific neuronal functions. © 2006 Wiley‐Liss, Inc.
Differential distribution of voltage‐gated potassium channels Kv 1.1–Kv1.6 in the rat retina during development
Authors: Höltje M. , Brunk I. , Große J. , Beyer E. , Veh R.W. , Bergmann M. , Große G. , Ahnert‐Hilger G.
Published: October 2006

The discharge behavior of neurons depends on a variable expression and sorting pattern of voltage‐dependent potassium (Kv) channels that changes during development. The rodent retina represents a neuronal network whose main functions develop after birth. To obtain information about neuronal maturation we analyzed the expression of subunits of the Kv1 subfamily in the rat retina during postnatal development using immunocytochemistry and immunoelectron microscopy. At postnatal day 5 (P5) all the α‐subunits of Kv1.1–Kv1.6 channels were found to be expressed in the ganglion cell layer (GCL), most of them already at P1 or P3. Their expression upregulates postnatally and the pattern and distribution change in an isoform‐specific manner. Additionally Kv1 channels are found in the outer and inner plexiform layer (OPL, IPL) and in the inner nuclear layer (INL) at different postnatal stages. In adult retina the Kv 1.3 channel localizes to the inner and outer segments of cones. In contrast, Kv1.4 is highly expressed in the outer retina at P8. In adult retina Kv1.4 occurs in rod inner segments (RIS) near the connecting cilium where it colocalizes with synapse associated protein SAP 97. By using confocal laser scanning microscopy we showed a differential localization of Kv1.1‐1.6 to cholinergic amacrine and rod bipolar cells of the INL of the adult retina. © 2006 Wiley‐Liss, Inc.
Raman study of lithium coordination in EMI‐TFSI additive systems as lithium‐ion battery ionic liquid electrolytes
Authors: Hardwick Laurence J. , Holzapfel Michael , Wokaun Alexander , Novák Petr
Published: October 2006

Raman spectroscopy was performed on various mixtures of the ionic liquid salt, 1‐ethyl‐3‐methylimidazolium‐bis(trifluoromethylsulfonyl)imide (EMI‐TFSI). When EMI‐TFSI is used in combination with a lithium salt, it could be a potential electrolyte for lithium‐ion or lithium metal batteries. The Raman spectra of EMI‐TFSI, EMI‐TFSI 0.5 M Li‐TFSI, EMI‐TFSI 0.5 M Li‐TFSI 2 M vinylene carbonate (VC) and EMI‐TFSI 0.5 Li‐TFSI 2 M ethylene carbonate (EC) were collected and compared. A comparison of the peak positions of the δs CF3 mode at 742 cm−1 demonstrates that when carbonate additives are present, the lithium ion is no longer interacting with the TFSI anion. Instead, it is coordinated with the carbon–oxygen double bond of the carbonates. Copyright © 2006 John Wiley & Sons, Ltd.
Heart rate of motor vehicle accident survivors in the emergency department, peritraumatic psychological reactions, ASD, and PTSD severity: A 6‐month prospective study
Authors: Kuhn Eric , Blanchard Edward B. , Fuse Tiffany , Hickling Edward J. , Broderick John
Published: October 2006

This small‐scale study investigates the relationships between the heart rate of motor vehicle accident survivors presenting in the emergency department (ED) and acute stress disorder (ASD) and posttraumatic stress disorder (PTSD) symptom severity. It also examines the relationships between the survivor's heart rate in the ED and peritraumatic dissociation and peritraumatic distress reported 2 weeks posttrauma. Fifty motor vehicle accident (MVA) survivors were assessed 2 weeks, 1 (N = 42), 3 (N = 37), and 6 months (N = 37) post‐MVA. The heart rate in the ED predicted self‐reported ASD symptom severity and clinician‐rated PTSD symptom severity at 6 months but not at 1 or 3 months. Survivors' heart rate in the ED was significantly correlated with peritraumatic dissociation but not peritraumatic distress. These findings support the role of elevated ED heart rate as a predictor of both ASD and chronic PTSD symptom severity and may help to clarify the discrepant findings of previous research.
PTSD as a mediator of sexual revictimization: The role of reexperiencing, avoidance, and arousal symptoms
Authors: Risser Heather J. , Hetzel‐Riggin Melanie D. , Thomsen Cynthia J. , McCanne Thomas R.
Published: October 2006

Theory and research suggest that posttraumatic stress disorder (PTSD) may mediate the relationship between child sexual abuse and adult sexual assault. However, little empirical research has examined the mediational role of PTSD. In the present study, the authors use structural equation modeling to examine the degree to which the three symptom clusters that define PTSD (reexperiencing, avoidance, and hyperarousal) contribute to sexual revictimization. To assess PTSD symptomatology, undergraduate women completed questionnaires (N = 1,449), which detailed the history and severity of childhood and adult sexual assault experiences. Results indicated that PTSD mediated sexual revictimization. When PTSD symptom clusters were examined individually, only the hyperarousal cluster was a significant mediator. Results are discussed in terms of information‐processing mechanisms that may underlie sexual revictimization.
Reduced heart rate responding to trauma reliving in trauma survivors with PTSD: Correlates and consequences
Authors: Halligan Sarah L. , Michael Tanja , Wilhelm Frank H. , Clark David M. , Ehlers Anke
Published: October 2006

The authors investigated whether heart rate (HR) responses to voluntary recall of trauma memories (a) are related to posttraumatic stress disorder (PTSD), and (b) predict recovery 6 months later. Sixty‐two assault survivors completed a recall task modeled on imaginal reliving in the initial weeks postassault. Possible cognitive modulators of HR responsivity were assessed; dissociation, rumination, trauma memory disorganization. Individuals with PTSD showed a reduced HR response to reliving compared to those without PTSD, but reported greater distress. Notably, higher HR response but not self‐reported distress during reliving predicted greater symptom reduction at follow‐up in participants with PTSD. Engagement in rumination was the only cognitive factor that predicted lower HR response. The data are in contrast to studies using trauma reminders to trigger memories, which have found greater physiological reactivity in PTSD. The authors' observations are consistent with models of PTSD that highlight differences between cued or stimulus‐driven retrieval and intentional trauma recall, and with E. B. Foa and M. J. Kozak's (1986) hypothesis that full activation of trauma memories facilitates emotional processing.
Dissemination of exposure therapy in the treatment of posttraumatic stress disorder
Authors: Cahill Shawn P. , Foa Edna B. , Hembree Elizabeth A. , Marshall Randall D. , Nacash Nitsa
Published: October 2006

Since the introduction of posttraumatic stress disorder (PTSD) into the Diagnostic and Statistical Manual of Mental Disorders, Third Edition (DSM‐III; American Psychiatric Association, 1980), considerable research has demonstrated the efficacy of several cognitive–behavioral therapy (CBT) programs in the treatment of chronic PTSD. Among these efficacious treatments is exposure therapy. Despite all the evidence for the efficacy of exposure therapy and other CBT programs, few therapists are trained in these treatments and few patients receive them. In this article, the authors review extant evidence on the reasons that therapists do not use these treatments and recent research on the dissemination of efficacious treatments of PTSD.
Formation of Honeycomb‐Patterned Polyetherketone Cardo (PEK‐C) Films in a Highly Humid Atmosphere
Authors: Tian Ye , Liu Shuang , Ding Huaiyu , Wang Lihua , Liu Biqian , Shi Yanqiao
Published: October 2006

Summary: The fabrication of honeycomb‐patterned films from PEK‐C in a humid atmosphere is reported. Some governing factors, such as the concentrations of the polymer solutions, the atmosphere humidity, and the volatility of the solvents, are tested. Moreover, by using PEK‐C, PLEG, and PPO, the different mechanisms between hydrophilic polymers and hydrophobic polymers on pattern formation are also studied.

Influence of the concentration on water droplet arrangement. Concentration: a) 1 and b) 2 g · L−1.

magnified image

Influence of the concentration on water droplet arrangement. Concentration: a) 1 and b) 2 g · L−1.
The mRNA expression of P450 aromatase, gonadotropin β‐subunits and FTZ‐F1 in the orange‐spotted grouper (Epinephelus Coioides) during 17α‐methyltestosterone‐induced precocious sex change
Authors: Zhang Weimin , Zhang Yong , Zhang Lihong , Zhao Huihong , Li Xin , Huang He , Lin Haoran
Published: October 2006

The orange‐spotted grouper Epinephelus coioides is a protogynous hermaphroditic fish, but the physiological basis of its sex change remains largely unknown. In the present study, the 2‐year‐old orange‐spotted grouper was induced to change sex precociously by oral administration of 17α‐methyltestosterone (MT, 50 mg/Kg diet, twice a day at daily ration of 5% bodyweight) for 60 days. The serum testosterone levels were significantly elevated after MT treatment for 20 and 40 days as compared to control, but the levels of serum estradiol (E2) remained unchanged. The expression of P450aromA in the gonad significantly decreased after MT treatment for 20, 40, and 60 days. Accordingly, the enzyme activity of gonadal aromatase was also lower. The expression of FSHβ subunit in the pituitary was significantly decreased after MT treatment for 20 days, but returned to the control levels after 40 and 60 days; however, the expression of LHβ subunit was not altered significantly by MT treatment. The expression of FTZ‐F1 in the gonad also decreased significantly in response to MT treatment for 40 and 60 days, but its expression in the pituitary was not altered significantly. Interestingly, when tested in vitro on ovarian fragments, MT had no direct effect on the expression of P450aromA and FTZ‐F1 as well as the activity of gonadal aromatase, suggesting that the inhibition of gonadal P450aromatase and FTZ‐F1 by MT may be mediated at upper levels of the brain‐pituitary‐gonadal axis. Taken together, these results indicated that FSH, P450aromA, FTZ‐F1, and serum testosterone are associated with the MT‐induced sex change of the orange‐spotted grouper, but the cause–effect relationship between these factors and sex change in this species remains to be characterized. Mol. Reprod. Dev. 74: 665–673, 2007. © 2006 Wiley‐Liss, Inc.
Transfer of spermatogenesis‐related cDNAs into eel testis germ‐somatic cell coculture pellets by electroporation: Methods for analysis of gene function
Authors: Miura C. , Kuwahara R. , Miura T.
Published: October 2006

Genes encoding spermatogenesis‐related substance (eSRSs) show unique expression patterns during spermatogenesis. To analyze their function, we developed a new assay system using gene transfer techniques combined with coculture of the eel germ‐somatic cells. First, we investigated the efficacy of in vitro electroporation transfer of gene into germ‐somatic cell pellets using green fluorescent protein (GFP) gene. Second, in order to define the function of the eSRSs, we electrophoretically transferred eel spermatogonial stem cell renewal factor (eSRS34) and eel spermatogenesis‐preventing substance (eSRS21) genes into germ‐somatic cell pellets. Presence of the transferred cDNA was examined by reverse transcription‐polymerase chain reaction (RT‐PCR). Furthermore, proliferating cells were detected histologically, after labeling with BrdU. Transfer of the eSRS34 gene induced spermatogonial stem cell renewal in the pellets. Moreover, 11‐ketotestosterone (11‐KT) treatment stimulated the proliferation of spermatogonia, which resulted in the appearance of late type B spermatogonia in the pellets. The proliferation of spermatogonia by 11‐KT stimulation was suppressed by transfer of the eSRS21 gene. These results indicate that the transferred eSRS34 and 21genes were functional in the pellets. Thus, an efficient in vitro gene transfer technique for coculture system of germ and somatic cell of Japanese eel was established. Mol. Reprod. Dev. 74: 420–427, 2007. © 2006 Wiley‐Liss, Inc.
Presentation of 3D isotropic imaging data for optimal viewing
Authors: Henkelman R. Mark , Baghdadi Leila , Sled John G.
Published: October 2006

Three‐dimensional (3D) isotropically sampled data facilitates retrospective viewing of arbitrarily aligned image planes and simplifies automated computer analysis of 3D structures. However, compared to acquisitions that employ thick slices, MRI acquisitions with isotropic sampling have a lower signal‐to‐noise ratio (SNR). A rater study was performed to examine viewer preference for the trade‐off between SNR and the partial‐volume effect of through‐plane averaging. A robust preference for a 5:1 ratio in through‐plane to in‐plane was found for a typical SNR of 11. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
Nurses are increasingly involved in pharmacovigilance in Sweden
Authors: Ulfvarson Johanna , Mejyr Stefan , Bergman Ulf
Published: October 2006

Introduction

In Sweden, voluntary adverse drug reaction (ADR) reporting started over 40 years ago to detect rare, serious, unexpected adverse, mainly type B, reactions. During the period 1965–2004, 92 000 reports were assessed. Since certain nurses are licensed to prescribe a limited number of drugs, nurses also form part of the reporting team.

Aim

To analyse the ADR reporting by nurses in Sweden.

Methods

All reports by nurses and other health‐care personnel entered into the Swedish ADRs database SWEDIS (Swedish Drug Information System) were retrieved for the 10‐year period 1995–2004 (Swedish population: 9 million). The intention was to analyse the nurses' reports from a quantitative and qualitative point of view.

Results

The total number of ADR reports has gradually increased during the past 10 years from 3000 to over 4000 in 2004 (465 per million inhabitants), an increase by 28%. All ADR reports originate from health care personnel. The nurses' contribution to the ADR reporting increased from 2–3% in the mid‐90s to 12% in 2004. The most common drugs involved in the nurses' reporting were various kinds of vaccines. Skin reactions dominated among the nurses' ADR reports. The ADRs reported by nurses were, as a consequence of many vaccine reports, compared to all reports, not so often classified as serious, but were on the other hand more often assessed with a causal relationship.

Conclusions

Nurses, in their position as drug administrators who record signs and symptoms of the patients, play an increasingly important role for detection of suspected ADRs and are now contributing to a significant amount of the ADR reporting in Sweden. Copyright © 2006 John Wiley & Sons, Ltd.
Estrogen signaling and disruption of androgen metabolism in acquired androgen‐independence during cadmium carcinogenesis in human prostate epithelial cells
Authors: Benbrahim‐Tallaa Lamia , Liu Jie , Webber Mukta M. , Waalkes Michael P.
Published: October 2006

BACKGROUND

Lethal prostate cancers often become androgen‐independent due to androgen receptor (AR) overexpression. The role of cadmium in prostate tumor progression was determined.

METHODS

Control and cadmium‐transformed prostate epithelial cells (CTPE) were compared for steroid‐induced proliferation, steroid receptor expression, and androgen metabolism.

RESULTS

CTPE cells showed rapid proliferation in complete medium and sustained proliferation in steroid‐reduced medium. Androgens stimulated significantly less cell proliferation and AR‐related genes expression in CTPE cells. 5α‐Dihydrotestosterone increased PSA expression more effectively in control cells. Flutamide reduced 5α‐dihydrotestosterone‐stimulated growth less effectively in CTPE cells compared to control. CTPE cells showed decreased p27 expression. Estrogen receptors were overexpressed and estradiol markedly stimulated proliferation in CTPE cells. In CTPE cells 5α‐aromatase was markedly increased, while 5α‐reductase was decreased.

CONCLUSIONS

Cadmium‐induced malignant transformation stimulates androgen independence, unrelated to AR expression or activity. Increased estrogen receptor and 5α‐aromatase expression suggest estrogen signaling may be critical to this process. Prostate © 2006 Wiley‐Liss, Inc.
Aberrant expression of SWI/SNF catalytic subunits BRG1/BRM is associated with tumor development and increased invasiveness in prostate cancers
Authors: Sun Aijing , Tawfik Ossama , Gayed Bishoy , Thrasher J. Brantley , Hoestje Sara , Li Chaoyang , Li Benyi
Published: October 2006

BACKGROUND

Brahma gene (BRM) and Brahma‐related gene 1 (BRG1) are major components with ATPase enzymatic activities in the nucleosome remodeling SWI/SNF complex, and their expression pattern in human prostate cancers is unknown.

METHOD

We analyzed a published cDNA microarray data set of prostate cancers for the expression of SWI/SNF genes, and then we evaluated the expression levels of BRG1 and BRM proteins with a semi‐quantitative immunohistochemistry (IHC) approach in a pairwise manner of malignant versus benign tissues from individual prostate cancers. The correlation of BRG1/BRM expression with clinical parameters was analyzed.

RESULTS

Microarray data showed an aberrant expression of BRG1 and BRM but not SNF5/INI1 genes in different stages of the disease course. In immunochemistry studies, BRG1 expression was significantly higher in malignant tissues compared to their benign compartments, and this difference was more profound in high‐grade cancers. Although BRM expression showed a heterogeneous pattern, the average level of BRM expression was lower in malignant tissues than that in benign tissues. More interestingly, BRG1 and BRM expression showed a reciprocal pattern in both benign and malignant tissues of individual cases. In malignant tissues, higher BRG1 but not BRM expression levels were associated with larger volume of tumor mass. Increased expression of BRG1 but not BRM protein was observed in invasive cancer cells. Consistently, overexpression of exogenous wild‐type BRG1 and BRM but not mutant BRG1 enhanced cancer cell invasion in an in vitro cell invasion assay.

CONCLUSIONS

We provide the first evidence that aberrant expression of BRG1 and BRM genes is associated with disease development and progression in prostate cancers and increased BRG1 expression may promote tumor growth and invasion. Prostate © 2006 Wiley‐Liss, Inc.
Dephasing of excited‐state excitons in InGaAs quantum dots
Authors: Borri P. , Langbein W. , Muljarov E. A. , Zimmermann R.
Published: October 2006

We measure the dephasing time of the first optically‐active excited‐state excitonic transition in strongly confined InGaAs quantum dots using transient four‐wave mixing. The optically‐driven excited‐state polarization shows a bi‐exponential decay with a significant fraction of the probed excited states exhibiting a very long dephasing time, in the nanosecond range at 10 K. The full time‐dependent four‐wave mixing polarization is microscopically calculated by taking into account both virtual and real acoustic phonon‐assisted transitions. The bi‐exponential decay is qualitatively explained by a model of two‐bright excitonic excited states non‐degenerate in the absence of in‐plane cylindrical symmetry. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Exciton dynamics in molecular aggregates
Authors: Augulis R. , Pugžlys A. , van Loosdrecht P. H. M.
Published: October 2006

The fundamental aspects of exciton dynamics in double‐wall cylindrical aggregates of cyanine dyes are studied by means of frequency resolved femtosecond pump‐probe spectroscopy. The collective excitations of the aggregates, resulting from intermolecular dipole‐dipole interactions have the characteristic property – the localization of the lowest lying exciton states. The experimentally observed outer‐to‐inner tubule excitonic energy transfer dynamics and the internal energy relaxation at low temperatures reveal a non‐equilibrium population of the excitonic subsystem. The analysis of measured dynamics reveals very fast picosecond timescale energy relaxation to the optically active energy states. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photoluminescence due to inelastic scattering processes of excitons in a GaN thin film grown by metalorganic vapor phase epitaxy
Authors: Tanaka H. , Ando M. , Uemura T. , Nakayama M.
Published: October 2006

We have investigated photoluminescence (PL) properties of a high quality GaN thin film grown by metalorganic vapor phase epitaxy under intense excitation conditions in a wide temperature range from 10 to 300 K. It is found that there are two types of PL band peculiar to intense excitation conditions. In a low temperature region below 80 K, the exciton‐exciton scattering dominates the PL, the so‐called P emission. On the other hand, in a high temperature region above ∼120 K, a PL band, which is different from the P emission, appears. The energy spacing between the new PL band and the fundamental A exciton linearly increases with an increase in temperature. In addition, the energy spacing is estimated to be zero at absolute zero temperature by extrapolation of the temperature dependence. These PL profiles indicate that the PL band observed in the high temperature regime originates from the exciton‐electron scattering. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photoluminesence and FTIR study of ZnO nanoparticles: the impurity and defect perspective
Authors: Xiong G. , Pal U. , Serrano J. G. , Ucer K. B. , Williams R. T.
Published: October 2006

We studied the possible correlations between defects and photoluminescence spectra in ZnO nanoparticles of sizes ranging from 43 nm to 73 nm in diameter. The defects and impurity contents were characterized by Fourier‐transform infrared (FTIR) spectroscopy. The results show fewer carboxylate and hydroxyl impurities for particles of larger sizes. No significant variation in oxygen vacancy content was found among samples. Annealing in vacuum at 300 °C significantly reduces the carboxylate and hydroxyl impurities in the samples. The total luminescence intensity (UV + visible) increases as the particle size grows for both the unannealed and annealed samples. This suggests that both types of luminescence are subject to non‐radiative quenching by near surface defect centers, possibly carboxylate and hydroxyl impurities. There may be quenching due to intrinsic lattice defects too. It is found that annealing in vacuum enhances the visible luminescence both absolutely and relative to the UV exciton luminescence. In addition to the 2.5 eV green luminescence peak, a peak centered at 2.8 eV can also be resolved, espeically for the 43 nm sample. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Trigonal Na3Li(SeO4)2·6H2O crystal – a novel SRS‐active material with high Raman gain coefficient
Authors: Kaminskii A. A. , Bohatý L. , Becker P. , Held P. , Eichler H. J. , Rhee H.
Published: October 2006

We discovered and characterized the χ (3)‐active Na3Li(SeO4)2·6H2O crystal with considerably high Raman gain coefficients for laser physics and nonlinear optics. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

magnified image

Section of the crystal structure of Na3Li(SeO4)2·6H2O, representing one sheet of [Na3O7(H2O)6] groups together with the linking tetrahedral groups [SeO4] and the double tetrahedra [O3SeOLi(H2O)3], that are formed by [SeO4] and [LiO(H2O)3]. Hydrogen atoms are marked with spheres. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Liquid chromatography/tandem mass spectrometry assay for the quantification of troxerutin in human plasma
Authors: Liu Fei , Xu Yu , Rui Lei , Gao Shu , Dong Haijun , Guo Qingxiang
Published: October 2006

A simple, rapid, sensitive and specific liquid chromatography/tandem mass spectrometry method was developed and validated to quantify troxerutin in human plasma. The analyte and rutin, used as the internal standard, were analyzed on a Phenomenex Synergi Fusion RP column interfaced with a triple‐quadrupole tandem mass spectrometer using positive electrospray ionization. Acetonitrile/water (20:80 v/v) was used as the isocratic mobile phase, with 0.1% formic acid in water. A simple sample preparation method of protein precipitation with perchloric acid was employed. The assay was linear over the concentration range 31.25–4000 pg/mL. Correlation coefficients generated by linear regression with a 1/x2 weighting factor ranged from 0.9991 to 0.9996. The intra‐ and inter‐day precision over the entire concentration range were less than 12.28%. The method was successfully applied to a pharmacokinetic study after oral administration of a 300 mg troxerutin drop pill to 18 healthy volunteers. Copyright © 2006 John Wiley & Sons, Ltd.
Internet companies' growth strategies: determinants of investment intensity and long‐term performance
Authors: Eisenmann Thomas R.
Published: October 2006

To exploit first‐mover advantages, pioneers may be motivated to amass customers before rivals enter the market. Likewise, when they enjoy increasing returns due to network effects, static scale economies, or learning effects, companies have incentives to invest aggressively in growth. This paper presents econometric analysis of factors that determined the intensity of Internet companies' investments in growth, and analyzes the long‐term performance consequences of such investments. Results indicate that first movers spent significantly more on upfront marketing than non‐pioneers. Contrary to expectations, however, firms in markets that exhibited increasing returns did not spend more on their early customer acquisition efforts than other sample companies. Although the typical sample company did not earn positive long‐term returns, heavy early investments in growth were nevertheless economically rational. In most cases, reducing marketing outlays would have worsened a bad outcome, consistent with an inverted ‘U’ relationship between long‐term returns and upfront marketing spending. Thus, the typical sample company invested in marketing, ex ante, at levels close to those that would have maximized returns, observed ex post. Copyright © 2006 John Wiley & Sons, Ltd.
The moderating influence of strategic orientation on the strategy formation capability–performance relationship
Authors: Slater Stanley F. , Olson Eric M. , Hult G. Tomas M.
Published: October 2006

An effective strategy formation capability is a complex organizational resource—a dynamic capability that should lead to superior performance. Strategy scholars have examined the strategy formation capability from many perspectives. However, no study has examined a comprehensive model of strategy formation in the context of the firm's strategic orientation. We develop and examine such a model. The results show that strategic orientation moderates the relationship between different elements of the strategy formation capability and performance. Copyright © 2006 John Wiley & Sons, Ltd.
Uterine artery Doppler velocimetry at 11–14 weeks in singleton pregnancies conceived by assisted reproductive technology
Authors: Prefumo F. , Fratelli N. , Soares S. C. , Thilaganathan B.
Published: October 2006

Objective

Singleton pregnancies resulting from assisted reproductive technologies (ART) have an increased risk of preterm delivery, pre‐eclampsia and intrauterine growth restriction. The aim of the present study was to determine whether first‐trimester trophoblastic invasion, as assessed by uterine artery Doppler velocimetry, is different in singleton pregnancies resulting from ART compared to those conceived naturally.

Methods

Case‐control study on 31 singleton ART pregnancies (26 in‐vitro fertilization–embryo transfer, five intracytoplasmic sperm injection) and 62 matched pregnancies conceived spontaneously. Doppler velocimetry was performed at 11–14 weeks of gestation.

Results

The mean resistance index (coefficient of variation) was 0.70 (17%) and 0.70 (18%) in ART and controls, respectively (P = 0.92). The corresponding values for mean pulsatility index were 1.40 (44%) and 1.47 (44%) in ART and controls, respectively (P = 0.58). Pregnancies with no, unilateral or bilateral diastolic notches were 48%, 26%, 26% and 36%, 37%, 27%, in ART and controls, respectively (P = 0.43).

Conclusion

There are no differences in uterine artery Doppler indices between pregnancies obtained by invasive ART and naturally conceived matched controls. This finding suggests that there is no major difference in trophoblastic invasion of the maternal spiral arteries between ART and spontaneous pregnancies. Copyright © 2006 ISUOG. Published by John Wiley & Sons, Ltd.
Double‐strand break repair and homologous recombination in Schizosaccharomyces pombe
Authors: Raji Hayatu , Hartsuiker Edgar
Published: October 2006

The study of double‐strand break repair and homologous recombination in Saccharomyces cerevisiae meiosis has provided important information about the mechanisms involved. However, it has become clear that the resulting recombination models are only partially applicable to repair in mitotic cells, where crossover formation is suppressed. In recent years our understanding of double‐strand break repair and homologous recombination in Schizosaccharomyces pombe has increased significantly, and the identification of novel pathways and genes with homologues in higher eukaryotes has increased its value as a model organism for double‐strand break repair. In this review we will focus on the involvement of homologous recombination and repair in different aspects of genome stability in Sz. pombe meiosis, replication and telomere maintenance. We will also discuss anti‐recombination pathways (that suppress crossover formation), non‐homologous end‐joining, single‐strand annealing and factors that influence the choice and prevalence of the different repair pathways in Sz. pombe. Copyright © 2006 John Wiley & Sons, Ltd.
DNA replication in the fission yeast: robustness in the face of uncertainty
Authors: Legouras Ioannis , Xouri Georgia , Dimopoulos Sotiris , Lygeros John , Lygerou Zoi
Published: October 2006

DNA replication, the process of duplication of a cell's genetic content, must be carried out with great precision every time the cell divides, so that genetic information is preserved. Control mechanisms must ensure that every base of the genome is replicated within the allocated time (S‐phase) and only once per cell cycle, thereby safeguarding genomic integrity. In eukaryotes, replication starts from many points along the chromosome, termed origins of replication, and then proceeds continuously bidirectionally until an opposing moving fork is encountered. In contrast to bacteria, where a specific site on the genome serves as an origin in every cell division, in most eukaryotes origin selection appears highly stochastic: many potential origins exist, of which only a subset is selected to fire in any given cell, giving rise to an apparently random distribution of initiation events across the genome. Origin states change throughout the cell cycle, through the ordered formation and modification of origin‐associated multisubunit protein complexes. State transitions are governed by fluctuations of cyclin‐dependent kinase (CDK) activity and guards in these transitions ensure system memory. We present here DNA replication dynamics, emphasizing recent data from the fission yeast Schizosaccharomyces pombe, and discuss how robustness may be ensured in spite of (or even assisted by) system randomness. Copyright © 2006 John Wiley & Sons, Ltd.
Quantitative analysis of a stand of Pinus densiflora undergoing succession to Quercus mongolica ssp. crispula: II. Growth and population dynamics of Q. mongolica ssp. crispula under the P. densiflora canopy
Authors: Kato Jun , Hayashi Ichiroku
Published: October 2006

We report here the results of an 8‐year study of the growth and population dynamics of Quercus mongolica ssp. crispula in a Pinus densiflora stand in a state of succession. In 1998, there were 169 Q. mongolica ssp. crispula individuals in a 400‐m2 plot under the P. densiflora canopy. This number remained nearly constant between 1998 and 2005. Mean recruitment of new individuals was 11 year−1, while mean mortality was 12 year−1. Of the 35 individuals ≥60 cm in height existing in 1998, 30 were still surviving in 2005. We were able to represent the height growth of Q. mongolica ssp. crispula individuals as H=30 [1+21.96 exp(−0.0839t)]−1, with t = years since 1998 and H = height in meters. Using this equation we predict that by 2015 the mean height of Q. mongolica ssp. crispula trees in the stand will exceed those of understory trees, such as Rhus trichocarpa and Prunusmaximowiczii. Once above the understory stratum, the Q. mongolica ssp. crispula trees can be expected to grow more rapidly due to the better light conditions, thereby rapidly reaching the canopy stratum of the P. densiflora stand.
Configuration of small patch reefs and population abundance of a resident reef fish in a complex coral reef landscape
Authors: Hattori Akihisa , Kobayashi Miyako
Published: October 2006

Habitat use by the resident coral reef anemonefish, Amphiprion frenatus, was examined in the complex coral reef landscape of Shiraho Reef, Ishigaki Island, Okinawa, Japan, using an enlarged color aerial photograph processed using image analysis software as an accurate field map. The anemonefish inhabit assemblages of the host sea anemone, Entacmaea quadricolor (clonal type), which inhabit various patch reefs in the back reef moat. We located all patch reefs inhabited by the host in the map based on snorkel observations: 297 anemonefish were found in 93 host assemblages in the study site of 2.9 ha. These patch reefs could be recognized by the reef colors, including the shadows (blackish color) in the photograph. Using image analysis software, the colors of the patch reefs were chosen and pixels with the same color values were regarded as potential habitat patches for the fish (PHPs). PHPs were 3D patch reefs (>0.5 m in height). Total areas (TA) and total perimeters (TP) of PHPs were measured in nine quadrats in the digitized aerial photograph. Host abundance and anemonefish abundance in a quadrat showed stronger correlations with the product of TA and TP of PHPs than TA alone. A site with numerous large 3D patch reefs (≥0.75 m2 in situ) can be a better habitat for the fish than other sites consisting of several huge 3D patch reefs of the same total area. The methodology applied here may be useful for assessing the quality of habitats for small resident animals in shallow subtidal reefs.
Determinants of Transposition Delay in the European Union
Authors: KAEDING MICHAEL
Published: October 2006

Europeanization involves the transposition and implementation of European legislation in EU member states. Whereas EU policy implementation is explicitly recognized as the responsibility of the member states, the new emphasis on benchmarking recognizes that different implementation strategies can be beneficial, provided the outcome is appropriate. New data representing the full EU transport acquis from 1957 to 2004 and the national transposition instruments derived from data bases for Germany, Greece, the UK, Spain and the Netherlands show that only 39 per cent of the acquis was transposed in time. Why do member states not transpose EU directives on time? Logistic and multinomial logistic analysis explains this in terms of the level of complexity of EU directives; the use of national legal instruments that include considerable de facto veto players; and the shorter the transposition time set in the directive, the more delayed the transposition process.
Effect of Al Addition on the Electronic Structure of Hafnia by Spatially Resolved Electron Energy Loss Spectroscopy
Authors: Li Q , Dai J , Gong X
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
A Trace Evidence Primer for Microscopists
Authors: Bisbing R
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Immunofluorescence Microscopy and Environmental Scanning Electron Microscopy Analysis of Stemonitis flavogenita
Authors: Pope R , Collins J , Collins S
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
STM Imaging of Vortices in FIB-Sculptured Mesoscopic Superconductors
Authors: Karapetrov G , Iavarone M , Fedor J , Marshall MT , Divan R , Kwok WK
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
STEM Z-contrast and Electron Energy Loss Spectroscopy Characterization of Co-doped TiO2 Thin Films
Authors: Fu L , Browning ND , Zhang S , Kundaliya DC , Ogale SB , Venkatesan T
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Spinodal Decomposition in Thick InGaN Layers Studied by Strain Field Analysis
Authors: Bartel T , Kisielowski C , Specht P
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Practical Application of Morphology Nomenclature for Pharmaceutical Materials
Authors: DiMemmo LM , Capecci L , Thomas J , Sarsfield B
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
TEM Study of Mn-Doped ZnO Thin Films Synthesized by PLD
Authors: Li XZ , Zhang J , Sellmyer DJ
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Experiences with Wet Capsule Imaging Exploring the Potential for Live Cell Imaging
Authors: Ackerley C , Nielsen C , Hawkins C
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Gridless TEM Supports Promise Greater Experimental Throughput
Authors: Hollis PS , Powell FR
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Morphological Study of a Novel Cysteine Protease Effect On Lepidopteran Larval Peritrophic Matrix
Authors: Mohan S , Ma P , Lawrence A , Monroe B , Luthe D
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Using Microscopy in Failure Analysis to Inspire Students
Authors: Jensen CL , Shipley RJ
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Investigation of Diffraction Condition and Convergent Probe Effects on Inelastic Mean Free Path Determination by Using a Cone-Shaped Silicon Crystal
Authors: Jin Q , Wang S
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
TEM Study of Precipitation Behavior of Diluted Cu-Co Alloys
Authors: Rocha AL , Solorzano G , Smith D , McCartney M
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Effect of Crystal Orientation on Imaging Contrast and Sputter Results during Focused Ion Beam Milling of Cu studied by FIB, EBSD, SEM, and AFM
Authors: Wendt U , Nolze G , Heyse H
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
[1-100]/(11-22) Twin Boundaries in Wurtzite ZnO and Group III-Nitrides
Authors: Yan Y , Al-Jassim M , Chisholm M , Boatner L , Pennycook SJ , Oxley M
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Limitations of Electron Energy-Loss Spectroscopy
Authors: Egerton R
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Translocation of Mitochondria in Cloned Porcine Embryos
Authors: Zhong ZS , Katayama M , Liu ZH , Hao YH , Lai LX , Li RF , Wax D , Samuel M , Sun Q-Y , Prather RS , Schatten H
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Environmental Transmission Electron Microscopy Using a Conventional TEM and a Gas Injection-Specimen Heating Holder
Authors: Kamino T , Yaguchi T , Watabe A , Saka H , Kishita K
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
The Role of Nitric Oxide in the Integrity of Endothelial Glycocalyx
Authors: Neamu R , Predescu S , Voyno-Yasenetskaya T , Malik A , Predescu D
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
XAS and TEM Study of the TiN Thin Films Grown by the Pulsed DC Sputtering Technique Assisted by Balanced Magnetron.
Authors: Moller JA Duarte , Ponce HE Esparza , Valenzuela C González
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
X-ray Microscopy Techniques for Nanostructure Analysis
Authors: Kirz J
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Effects of Lithium Doping and Post-processing on the Cathodoluminescence of Zinc Oxide Nanoparticles
Authors: McBean K , Phillips M , Drouin D
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Development of Ultra-Soft X-ray Spectrometer for Electron Probe Microanalysis
Authors: Fukushima S , Kimura T , Ogiwara T , Tsukamoto K , Tazawa T , Tanuma S
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006
Nanoscale Characterization of Materials for Magnetic Recording Applications
Authors: Larson D
Published: October 2006

Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006