bluuebunny/crossref_metadata_2025 huggingface dataset:
Relative importance of direct and trophic uranium exposures in the crayfish Orconectes limosus: Implication for predicting uranium bioaccumulation and its associated toxicity
Authors: Simon Olivier , Floriani Magali , Camilleri Virginie , Gilbin Rodolphe , Frelon Sandrine
Published: November 2012

Pollutants that occur at sublethal concentrations in the environment may lead to chronic exposure in aquatic organisms. If these pollutants bioaccumulate, then organisms higher in the food chain may also be at risk. Increased attention has thus been focused on the relative importance of dietary uptake, but additional knowledge of the cellular distribution of metals after dietary exposure is required to assess the potential toxicity. The authors address concerns relating to increasing uranium (U) concentrations (from 12 µg/L to 2 mg/L) in the freshwater ecosystem caused by anthropogenic activities. The objective of the present study is to compare uranium bioaccumulation levels in tissues and in the subcellular environment. The authors focused on the cytosol fraction and its microlocalization (TEM-EDX) in the gills and the hepatopancreas (HP) of the crayfish Orconectes limosus after 10 d of direct exposure (at concentrations of 20, 100, and 500 µg/L) and five trophic exposure treatments (at concentrations from 1 to 20 µg/g). Results indicated that adsorption of uranium on the cuticle represents the main contribution of total uranium accumulation to the animal. Accumulation in the gills should be considered only as a marker of waterborne uranium exposure. Accumulation in the HP after trophic environmental exposure conditions was higher (18.9 ± 3.8 µg/g) than after direct exposure. Moreover, no significant difference in the subcellular distribution of uranium (50%) in HP was observed between animals that had been exposed to both types of treatment. A potential toxic effect after uranium accumulation could therefore exist after trophic exposure. This confirms the need to focus further studies on the metal (uranium) risk assessment. Environ. Toxicol. Chem. 2013;32:410–416. © 2012 SETAC
Effects-based marine ecological risk assessment at a polychlorinated biphenyl-contaminated site in Saglek, Labrador, Canada
Authors: Brown Tanya M. , Kuzyk Zou Zou A. , Stow Jason P. , Burgess Neil M. , Solomon Steve M. , Sheldon Tom A. , Reimer Ken J.
Published: November 2012

Although the presence and distribution of polychlorinated biphenyls (PCBs) in Arctic marine environments has been well documented, the implications for the health of biota are poorly understood. In the present study, multiple lines of evidence, including site-specific effects data, were used to assess PCB-related risks to marine biota at a contaminated military site in Saglek Bay, Labrador, Canada, from 1997 to 1999. Risks were evaluated for three components of the ecosystem: benthic invertebrates, a bottom-feeding fish (shorthorn sculpin, Myoxocephalus scorpius), and a diving seabird (black guillemot, Cepphus grylle). Average sediment PCB concentrations exceeded the Canadian interim sediment quality guideline level by 41-fold. However, sediment toxicity testing and a benthic community survey showed no evidence of adverse effects. In contrast, shorthorn sculpin and black guillemot PCB exposures (measured as sum of 55 congeners) were elevated enough to pose risks to survival or reproduction. Based on the collective evidence, the authors estimated that risks were posed by sediment PCB concentrations greater than 77 ng/g dry weight for black guillemots and 750 ng/g dry weight for shorthorn sculpins. The present study, along with two parallel studies, provided information to support the management decisions concerning potential remedial action on the contaminated sediments. This ecological risk assessment describes the steps and rationale taken to evaluate the risk posed by an area of PCB-contaminated marine sediments in an otherwise relatively pristine northern coastal environment. Environ. Toxicol. Chem. 2013;32:453–467. © 2012 SETAC
Trends in psychotropic drug prescribing in Norwegian nursing homes from 1997 to 2009: a comparison of six cohorts
Authors: Ruths Sabine , Sørensen Pernille Hegre , Kirkevold Øyvind , Husebø Bettina S. , Krüger Kjell , Halvorsen Kjell H , Selbæk Geir
Published: November 2012

Background

Psychotropic drugs are extensively prescribed for the treatment of neuropsychiatric symptoms, despite modest efficacy and severe side effects.

Aims

We examined trends in psychotropic drug prescribing in Norwegian nursing homes from 1997 to 2009, in order to gain insight in practice development.

Methods

The study is a secondary data analysis of six cross‐sectional nursing home studies conducted between 1997 and 2009. Patients aged >65 years were included. We compared the prevalence of psychotropic drugs (antipsychotics, anxiolytics, hypnotics, and antidepressants). Associations between prescription of psychotropics, and patients' age, gender, type of ward, and year of data collection were examined by univariate analysis and logistic regression.

Results

Altogether, 7 661 patients (mean age 85.2 years, 72.6% women) were included. Prevalence of all psychotropic drugs combined increased from 57.6% to 70.5%, anxiolytics from 14.9% to 21.9%, hypnotics from 14.5% to 22.9%, and antidepressants from 31.5% to 50.9%. Prevalence of antipsychotics varied between extremes 21.1% and 25.6%. Less prescribing of older drugs was exceeded by an increase in newer drug types. Concomitant prescribing of two or more psychotropic drugs increased from 21% to 33%. Predictors of psychotropic drugs were female gender (except antipsychotics), as well as age <80 years, and residency in special care units (except hypnotics).

Conclusions

Prescribing of psychotropic drugs in nursing homes has increased considerably, especially regarding antidepressants. Explanations for this trend need to be further explored. Copyright © 2012 John Wiley & Sons, Ltd.
Osteogenesis and expression of the bone marrow niche in endothelial cell‐depleted HipOPs
Authors: McKenzie Kristen P. , Mayer Dana C. , Aubin Jane E.
Published: November 2012

The identification and purification of murine multipotent mesenchymal stem cells (MSCs) have been difficult due to their low frequency, the presence of contaminating cell types and lack of unambiguous markers. Using a magnetic micro‐beads negative selection technique to remove hematopoietic cells from mouse bone marrow stromal cells (BMSCs), our lab recently isolated a highly purified osteoprogenitor (HipOP) population that was also enriched for other mesenchymal precursors, including MSCs [Itoh and Aubin, 2009]. We now report that HipOPs are also highly enriched in vascular endothelial cells (VECs), which we hypothesized were an accessory cell type regulating osteogenesis. However, when VECs were immunodepleted from HipOPs with anti‐CD31 antibodies, the resulting CD31(−) HipOP population had equal osteogenic capacity to the HipOPs in vitro and in vivo. Analysis of gene expression of Ncad, Pth1r, Ang1, Cxcl12, Jag1, Pdgfr‐β, α‐sma, Desmin, and Ng2 suggested that both HipOPs and CD31(−) HipOPs are hemopoietic stem cell (HSC) niche populations. However, the data support the view that osteoblast differentiation and depletion of VECs modulate the HSC niche. J. Cell. Biochem. 114: 1066–1073, 2013. © 2012 Wiley Periodicals, Inc.
Alterations in replication timing of cancer‐related genes in malignant human breast cancer cells
Authors: Fritz Andrew , Sinha Seema , Marella Narasimharao , Berezney Ronald
Published: November 2012

The replication timing of nine genes commonly involved in cancer was investigated in the MCF10 cell lines for human breast cancer progression. Six of these nine genes are part of a constellation of tumor suppressor genes that play a major role in familial human breast cancer (TP53, ATM, PTEN, CHK2, BRCA1, and BRCA2). Three other genes are involved in a large number of human cancers including breast as either tumor suppressors (RB1 and RAD51) or as an oncogene (cMYC). Five of these nine genes (TP53, RAD51, ATM, PTEN, and cMYC) show significant differences (P < 0.05) in replication timing between MCF10A normal human breast cells and the corresponding malignant MCF10CA1a cells. These differences are specific to the malignant state of the MCF10CA1a cells since there were no significant differences in the replication timing of these genes between normal MCF10A cells and the non‐malignant cancer MCF10AT1 cells. Microarray analysis further demonstrated that three of these five genes (TP53, RAD51, and cMYC) showed significant changes in gene expression (≥2‐fold) between normal and malignant cells. Our findings demonstrate an alteration in the replication timing of a small subset of cancer‐related genes in malignant breast cancer cells. These alterations partially correlate with the major transcriptional changes characteristic of the malignant state in these cells. J. Cell. Biochem. 114: 1074–1083, 2013. © 2012 Wiley Periodicals, Inc.
CREB‐mediated Bcl‐2 expression contributes to RCAN1 protection from hydrogen peroxide‐induced neuronal death
Authors: Kim Seon Sook , Jang Shin Ah , Seo Su Ryeon
Published: November 2012

Regulator of calcineurin 1 (RCAN1) is located on the Down syndrome critical region (DSCR) locus in human chromosome 21. In this study, we investigated the functional role of RCAN1 in the reactive oxygen species (ROS)‐mediated neuronal death signaling. We found that RCAN1 was able to protect the cells from H2O2‐induced cytotoxicity. The expression of RCAN1 caused an inhibition of the H2O2‐induced activation of mitogen‐activated protein kinases (MAPKs) and AP‐1. In contrast, RCAN1 significantly enhanced the activity of cAMP response element‐binding protein (CREB). Furthermore, RCAN1 induced the expression of the CREB target gene, Bcl‐2. Consistently, knockdown of endogenous RCAN1 using shRNA down regulated the phosphorylation of CREB and the expression of Bcl‐2, which protects the cells from H2O2‐induced cytotoxicity. Our data provide a new mechanism for the cytoprotective function of RCAN1 in response to oxidant‐induced apoptosis. J. Cell. Biochem. 114: 1115–1123, 2013. © 2012 Wiley Periodicals, Inc.
New insights into the role of Runx1 in epithelial stem cell biology and pathology
Authors: Scheitz Cornelia Johanna Franziska , Tumbar Tudorita
Published: November 2012

The transcription factor Runx1 has been studied in leukemia and blood for decades, but recently it has been also implicated in epithelial biology and pathology. Particularly in mouse skin Runx1 modulates Wnt signaling levels thereby regulating timely induction of hair follicle specification, proper maturation of the emerging adult hair follicle stem cells in embryogenesis, and timely stem cell (SC) activation during adult homeostasis. Moreover, Runx1 acts as a tumor promoter in mouse skin squamous tumor formation and maintenance, likely by repressing p21 and promoting Stat3 activation. Similarly, Runx1 is essential for oral epithelium tumorigenesis mediated in mice by Ras, and for growth of three kinds of human epithelial cancer cells. In contrast, Runx1 has a tumor suppressor function in the mouse intestine and shows tumor subtype specific behavior in human breast cancer. Multiple studies revealed Runx1 SNPs to be associated with human cancers and autoimmune disease. With this information as background, the field is poised for functional and mechanistic studies to elucidate the role of Runx1 in formation and/or progression of epithelial‐based human disease. J. Cell. Biochem. 114: 985–993, 2013. © 2012 Wiley Periodicals, Inc.
The current state of bone loss research: Data from spaceflight and microgravity simulators
Authors: Nagaraja Mamta Patel , Risin Diana
Published: November 2012

Bone loss is a well documented phenomenon occurring in humans both in short‐ and in long‐term spaceflights. This phenomenon can be also reproduced on the ground in human and animals and also modeled in cell‐based analogs. Since space flights are infrequent and expensive to study the biomedical effects of microgravity on the human body, much of the known pathology of bone loss comes from experimental studies. The most commonly used in vitro simulators of microgravity are clinostats while in vivo simulators include the bed rest studies in humans and hindlimb unloading experiments in animals. Despite the numerous reports that have documented bone loss in wide ranges in multiple crew members, the pathology remains a key concern and development of effective countermeasures is still a major task. Thus far, the offered modalities have not shown much success in preventing or alleviating bone loss in astronauts and cosmonauts. The objective of this review is to capture the most recent research on bone loss from spaceflights, bed rest and hindlimb unloading, and in vitro studies utilizing cellular models in clinostats. Additionally, this review offers projections on where the research has to focus to ensure the most rapid development of effective countermeasures. J. Cell. Biochem. 114: 1001–1008, 2013. © 2012 Wiley Periodicals, Inc.
Comprehensive characterization of Annonaceous acetogenins within a complex extract by HPLC‐ESI‐LTQ‐Orbitrap® using post‐column lithium infusion
Authors: Le Ven Jessica , Schmitz‐Afonso Isabelle , Lewin Guy , Laprévote Olivier , Brunelle Alain , Touboul David , Champy Pierre
Published: November 2012

Annonaceous acetogenins (AAGs) are a homogenous class of polyketides proposed as environmental neurotoxins. Previous dereplication studies of AAGs were limited by the use of low‐resolution mass spectrometers. Only poor information in terms of structures was provided due to the limited fragmentation of protonated or sodium cationized species. An innovative approach, using reversed‐phase high‐performance liquid chromatography coupled to a hybrid linear ion trap / orbitrap mass spectrometer (LTQ‐Orbitrap®), was therefore performed. Sensitivity was enhanced by post‐column infusion of lithium, since AAGs have a high affinity for this cation. High level of structural information was obtained from low‐energy‐collision‐induced dissociation fragmentation experiments of lithium‐cationized AAGs ([M + Li]+ ions) as demonstrated with purified standards. The method was then applied to a total ethyl‐acetate extract prepared from commercial soursop nectar (Annona muricata L.). The sensitivity, mass accuracy and specific fragmentation patterns proved to be particularly useful for characterization of the AAGs. Typical structural identification procedure and unexpected observations for specific structural types are illustrated, with major and minor compounds. Copyright © 2012 John Wiley & Sons, Ltd.
Reaction pathways of Sc+ (3D, 1D) and Fe+ (6D, 4F) with acetone in the gas phase: metal ion oxidation and acetone deethanization
Authors: Chen Xiangfeng , Zang Hao , Yeung Hoi‐Sze , Lu Xiaoqing , Dominic Chan T‐W.
Published: November 2012

The reactions of Sc+ (3D, 1D) and Fe+ (6D, 4 F) with acetone have been investigated in both high‐ and low‐spin states using density functional theory. Our calculations have indicated that oxidation of Sc+ by acetone can take place by (1) metal‐mediated H migration, (2) direct methyl‐H shift and/or (3) C = O insertion. The most energetically favorable pathway is metal‐mediated H migration followed by intramolecular ScO+ rotation and dissociation. For the deethanization of acetone mediated by Fe+, the reaction occurs on either the quartet or sextet surfaces through five elementary steps, i.e. encounter complexation, C–C bond activation, methyl migration, C–C coupling and non‐reactive dissociation. The rate‐determining step along the quartet‐state potential‐energy surface (PES) is similar to that in the case of Ni+ (2 F, 3d9), namely the methyl‐migration step. For the sextet‐state PES, however, the energy barrier for methyl migration is lower than that for C–C bond activation, and the rate‐determining step is C–C coupling. In general, the low‐spin‐state pathways are lower in energy than the high‐spin‐state pathways; therefore, the reaction pathways for the oxidation of Sc+ and the Fe+‐mediated deethanization of acetone mostly involve the low‐spin states. Copyright © 2012 John Wiley & Sons, Ltd.
Exploring the intrinsic polar [4 + 2+] cycloaddition reactivity of gaseous carbosulfonium and carboxonium ions
Authors: Basher Muftah M. , Corilo Yuri E. , Sparrapan Regina , Benassi Mario , Augusti Rodinei , Eberlin Marcos N. , Riveros José M.
Published: November 2012

Gas‐phase reactions of model carbosulfonium ions (CH3‐S+ = CH2; CH3CH2‐S+ = CH2 and Ph‐S+ = CH2) and an O‐analogue carboxonium ion (CH3‐O+ = CH2) with acyclic (isoprene, 1,3‐butadiene, methyl vinyl ketone) and cyclic (1,3‐cyclohexadiene, thiophene, furan) conjugated dienes were systematically investigated by pentaquadrupole mass spectrometry. As corroborated by B3LYP/6‐311 G(d,p) calculations, the carbosulfonium ions first react at large extents with the dienes forming adducts via simple addition. The nascent adducts, depending on their stability and internal energy, react further via two competitive channels: (1) in reactions with acyclic dienes via cyclization that yields formally [4 + 2+] cycloadducts, or (2) in reactions with the cyclic dienes via dissociation by HSR loss that yields methylenation (net CH+ transfer) products. In great contrast to its S‐analogues, CH3‐O+ = CH2 (as well as C2H5‐O+ = CH2 and Ph‐O+ = CH2 in reactions with isoprene) forms little or no adduct and proton transfer is the dominant reaction channel. Isomerization to more acidic protonated aldehydes in the course of reaction seems to be the most plausible cause of the contrasting reactivity of carboxonium ions. The CH2 = CH‐O+ = CH2 ion forms an abundant [4 + 2+] cycloadduct with isoprene, but similar to the behavior of such α,β‐unsaturated carboxonium ions in solution, seems to occur across the C = C bond. Copyright © 2012 John Wiley & Sons, Ltd.
Size effects on phonon localization and Raman enhancement in silicon nanotips
Authors: Hofmann Mario , Hsieh Ya‐Ping , Liang Chi‐Te , Chen Yang‐Fang
Published: November 2012

Silicon nanotip arrays exhibit a wide variety of interesting optical and electronic properties associated with their dimensionality. We here investigate the effect of size‐induced changes on phonon localization and explain the enhanced Raman response. The occurrence of normally forbidden transitions in the photoluminescence spectra provides evidence for the predicted localization effect. Spatially resolved Raman spectroscopy reveals a continuous change of the silicon Raman peak position and peak width along the nanotip that is attributed to a smooth change between bulk properties at the base to size‐induced phonon confinement in the apex of the nanotip. This approach allows to exclude heating effects that normally overwhelm the phonon confinement signature. The Raman spectra are in excellent agreement with the spatial correlation model and the extracted correlation length is comparable to the tip dimensions. The observed phonon confinement coincides with an enhancement of the Raman scattering efficiency at the tip apex and results in a 40‐fold increase of the sample's Raman intensity compared with bulk silicon. These results provide a step toward the integration of Si based optoelectronic devices. Copyright © 2012 John Wiley & Sons, Ltd.
Structural changes induced by interactions between thyroid hormones and phospholipid membranes: a Raman Spectroscopy study
Authors: Petruk Ariel A. , Álvarez Rosa María S.
Published: November 2012

Previous reports from our laboratory have shown that thyroid hormones induce changes in the fluidity and permeability of phospholipid bilayers and modify the transmembrane dipolar organization according to their iodine content. The interactions of T2, T3, and T4 with a model membrane of dilauroylphosphatidylcholine in the liquid‐crystalline phase were analyzed by confocal Raman spectroscopy. Insights into the nature of the hormone effects on the membrane properties, as well as the structural adaptations of the hormones in response to the lipid environment were derived from the spectral changes. The series of progressive iodine substituents on the ring‐β allowed us to correlate the hormone effects according to the number and the orientation of the iodine atoms. T4 was responsible for producing the highest alteration in the hydrophobic region of the membrane. Copyright © 2012 John Wiley & Sons, Ltd.
Issues relating to selective reporting when including non‐randomized studies in systematic reviews on the effects of healthcare interventions
Authors: Norris Susan L , Moher David , Reeves Barnaby C , Shea Beverley , Loke Yoon , Garner Sarah , Anderson Laurie , Tugwell Peter , Wells George
Published: November 2012

Background

Selective outcome and analysis reporting (SOR and SAR) occur when only a subset of outcomes measured and analyzed in a study is fully reported, and are an important source of potential bias.

Key methodological issues

We describe what is known about the prevalence and effects of SOR and SAR in both randomized controlled trials (RCTs) and non‐randomized studies (NRS), and the effects of SOR and SAR on summary effect estimates and conclusions in systematic reviews of the effectiveness of healthcare interventions.

Guidance

Review authors should always suspect SOR and SAR in reviews that include NRS, assess primary studies for the risk of bias, and make reasonable attempts to retrieve study protocols or other documentation developed before study recruitment began. There are clues that may suggest SOR or SAR in NRS, including differences between the methods and results sections of the publication, study funder, and differences between study protocol or registration information and the study report.

Conclusion

Existing evidence about reporting biases in primary studies comes almost exclusively from methodological reviews of RCTs. The prevalence and impact of SOR and SAR in NRS are likely even greater than in RCTs but it is difficult to identify and confirm selective reporting in NRS. Copyright © 2012 John Wiley & Sons, Ltd.
Psychographics: Static or Dynamic?
Authors: Park Jeong‐Yeol , Jang SooCheong (Shawn)
Published: November 2012

Plog has suggested that psychographics are determinants of travel patterns and preferences. However, given that satisfaction is an important factor determining revisit intention, this study questioned Plog's static model of psychographics. We proposed that allocentrics could have high revisit intentions if they are satisfied. Thus, this study attempted to verify whether Plog's psychographics are static or dynamic. Revisit intentions were compared among psychographics at different satisfaction levels, and the results showed that the revisit intention of allocentrics did not differ from psychocentrics when satisfied. The results provide evidence that psychographic segmentation may not be static, especially when satisfaction is considered. Copyright © 2012 John Wiley & Sons, Ltd.
Vernetzt geplant — Synthesedesign ohne Chemiker?
Authors: Wegner Hermann A.
Published: November 2012

Eine effiziente Syntheseroute zu einem Molekül zu planen, stellt höchste Anforderungen an das Wissen und die Erfahrung des Chemikers. Chemische Netzwerke sind ein Hilfsmittel für diese Aufgabe.
Strukturaufklärung mit NMR in der Synthesechemie
Authors: Kuhn Stefan , Schlörer Nils E.
Published: November 2012

Die weiterentwickelte Software nmrshiftdb2 bietet frei zugänglich Daten und Werkzeuge für die Zuordnung und Struktursuche von und mit NMR‐Spektren. Außerdem gibt es ein Modul zur elektronischen Laboradministration für universitäre NMR‐Abteilungen.
Tonscherben im Elektronenmikroskop
Authors: Preisinger Anton , Aslanian Selma , Wernisch Johann
Published: November 2012

Eigneten sich die prähistorischen Tongefäße, die Archäologen in der Nähe einer Steinsalzlagerstätte fanden, tatsächlich zur Herstellung von Salzkristallen aus Sole? Wichtige Hinweise liefert die Rasterelektronenmikroskopie mit Mikrosonde.
Advancing Project Management: Authenticating the Shift from Process to “Nuanced” Project-Based Management in the Ambidextrous Organization
Authors: Leybourne Stephen A. , Sainter Phillip
Published: November 2012

In this article, we recognize the ambidextrous nature of organizations, and use this concept to analyze the changing nature of the understood project management paradigm. Specifically, the ambidextrous nature of the modern organization explores and leverages both exploitation of existing processes, frameworks, and structures, and the exploration of new ways of achieving tasks and activities, embracing improvisational and nonroutine activity, as well as the more rigid and documented process-based activity embedded in organizational procedures. Initially, we examine the emergence of new and novel developments within both the processual and the behavioral domains within project-based management. A discussion follows that focuses on the relevance and importance of those developments from both areas and the likelihood of their influencing or contributing to a new and improved project management paradigm. Management by projects is an interesting developing field, and one that is growing in influence. The analysis we undertake points toward the emergence of a new project management paradigm, which reflects a distinct shift from the understood project management life cycle, toward a model where planning and execution merge into a more “organic” archetype, requiring skills and techniques that are advancing the required skill set of the competent project manager.
Elucidating the behavior of physical fatigue and mental fatigue in cancer patients: a review of the literature
Authors: de Raaf P. J. , de Klerk C. , van der Rijt C. C. D.
Published: November 2012

Background

Although the multidimensional nature of cancer‐related fatigue is widely accepted, it could be questioned whether fatigue dimensions are expressions of one symptom (multidimensional concept) or expressions of several phenomena that are all called fatigue but actually are separate symptoms (multiple‐symptom concept).

Methods

Therefore, we investigated in this review whether physical fatigue and mental fatigue behave differently in cancer patients by studying their intensity in different stages of cancer, their changes in intensity during anti‐tumor therapy, the variables to which they are related, and their changes in intensity by interventions on fatigue.

Results

In some studies, physical fatigue and mental fatigue behaved similarly: they were both more intense in cancer patients than in healthy controls, and sometimes, they had the same course during anti‐tumor therapy, or both improved during an intervention. On the contrary, there were some studies suggesting that physical fatigue and mental fatigue behaved differently: physical fatigue seemed to be more prominent than mental fatigue in some stages of the disease trajectory; several studies reported changes in physical fatigue not accompanied by changes in mental fatigue during anti‐tumor therapy or by interventions aimed to relieve fatigue; and physical fatigue and mental fatigue had different correlates.

Conclusions

In conclusion, we found some studies in which physical fatigue and mental fatigue behaved differently. These findings might indicate that physical fatigue and mental fatigue are separate phenomena. To prove this multiple‐symptom concept, studies on the pathophysiological mechanisms leading either to physical fatigue or to mental fatigue are urgently needed. Copyright © 2012 John Wiley & Sons, Ltd.
Neuromuscular Stimulation of Quadriceps in Patients Hospitalised during an Exacerbation of COPD: A Comparison of Low (35 Hz) and High (50 Hz) Frequencies
Authors: Chaplin Emma Jane Louise , Houchen Linzy , Greening Neil J. , Harvey‐Dunstan Theresa , Morgan Michael D. , Steiner Michael C. , Singh Sally J.
Published: November 2012

Background

Neuromuscular electrical stimulation (NMES) has shown to improve skeletal muscle strength and exercise capacity in stable patients with chronic obstructive pulmonary disease (COPD). Variations in NMES protocols are considerable. We aimed to compare changes in muscle strength after high‐frequency and low‐frequency NMES in patients admitted to hospital with an acute exacerbation of COPD.

Methods

Patients were referred for inpatient (IP) rehabilitation during hospitalisation for an acute worsening of their COPD. They received 30‐minute daily NMES to both quadriceps at a frequency of 35 or 50 Hz. NMES intensity was titrated to patients' tolerance. Isometric quadriceps muscle strength and endurance walking (ESWT) time were measured at baseline and on hospital discharge.

Results

A total of 10 patients in each treatment group underwent NMES during hospitalisation (mean [SD] age 68.0 [±7.4] years, FEV1 0.99 L [±0.58], FEV1/FVC 47% [± 27%], MRC 5 [IQR ±1]). There were no significant differences in baseline characteristics between groups. Muscle strength (legs combined) increased in both groups regardless of the NMES frequency used (35 Hz ‐ 3.8 ± 4.9; 50 Hz ‐ 3.4 ± 5.5 kg). This was only significant within the 35 Hz group. The change in ESWT also showed a trend to increase in both groups (35 Hz ‐ 109 ± 92.7; 50 Hz ‐ 145.6 ± 94.7). There was no significant difference between groups for either outcome.

Conclusion

NMES is a feasible intervention to improve muscle strength in a cohort of patients admitted with an exacerbation of COPD. The response appears to be independent of the frequency used and both were well‐tolerated. Copyright © 2012 John Wiley & Sons, Ltd.
Optical and scintillation properties of bulk ZnO crystal
Authors: Yanagida Takayuki , Fujimoto Yutaka , Yamanoi Kohei , Kano Masataka , Wakamiya Akira , Kurosawa Shunsuke , Sarukura Nobuhiko
Published: November 2012

Single crystal bulk ZnO scintillator grown by the hydrothermal method was tested on its scintillation performances. In X‐ray induced radio luminescence spectrum, it exhibited two intense emission peaks at 400 and 550 nm. The former was ascribed to the free and bound exciton related luminescence and the latter to oxygen vacancy related one, respectively. X‐ray induced scintillation decay time of the exciton related emission measured by the pulse X‐ray streak camera system resulted ∼ 4 ns. Finally, the light yield under 241Am 5.5 MeV α‐ray was examined and it resulted ∼ 500 ph/5.5 MeV‐α.(© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Current‐injected narrow linewidth emissions from organic‐crystal light‐emitting transistors having a diffraction grating
Authors: Okada Akinori , Makino Yoshitaka , Hotta Shu , Yamao Takeshi
Published: November 2012

We have fabricated light‐emitting field‐effect transistors (LEFETs) using p‐type organic crystals directly grown onto a two‐dimensional polymer diffraction grating made of a triangular lattice of circular air holes. An n‐type organic thin film was inserted between the crystal and the metal electrode. Distinct current‐injected spectrally narrow linewidth emissions (NLEs) were observed under application of alternating‐current voltages to the gate contact. The NLE peaks were related to the combined refractive index of the p‐type crystal and the grating. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Anisotropy antireflection TiO2 nanoparticle films fabricated with directed cluster beam deposition
Authors: Mao Peng , Chen Jinhui , Zhou Yang , Liao Kaiming , Zhao Bo , Han Junhao , Wang Guanghou , Han Min
Published: November 2012

Antireflection TiO2 nanoparticle film was fabricated on silica glass substrate by using directed cluster beam deposition method. Self‐shadowing becomes a dominant growth mechanism for nanoparticle deposition at sufﬁciently large incident angles, which results in extremely porous nanoparticle stacking and yields excellent control over the refractive index profile. Inclined columnar and porous microstructure was confirmed with SEM and AFM. The TiO2 nanoparticle films show ultra‐high transmittance, broadband and omnidirectional characters, which can be attributed to its porous structure and modulated refractive index. We also found that the film displays an angular selective optical transmittance. The highest antireflection enhancement of the light transmission can be obtained for light incidence along the nanoparticle columns. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Pharmacokinetics of Hesperetin and Naringenin in the Zhi Zhu Wan, a Traditional Chinese Medicinal Formulae, and its Pharmacodynamics Study
Authors: Sun Hui , Dong Tianwei , Zhang Aihua , Yang Jinfeng , Yan Guangli , Sakurai Tetsuro , Wu Xiuhong , Han Ying , Wang Xijun
Published: November 2012

Zhi Zhu Wan (ZZW), a classical Chinese medical formulae consisted of Atractylodes Rhizome and Fructus Citrus Immaturus, has been commonly used for treatment of gastrointestinal diseases. Hesperetin and naringenin are the main components of ZZW, and both can alleviate intestinal tract disorders. In this work, plasma pharmacokinetics and pharmacodynamics characteristics of ZZW after oral administration were investigated using a rapid and sensitive ultra performance liquid chromatography–tandem mass spectrometry method with an electrospray ionization source in positive ion mode. Biosamples were prepared using methanolic precipitation, and the separation of hesperetin and naringenin was achieved on a Waters ACQUITY HSS BEH (2.1 mm × 5 mm, 1.7 µm) column by linear gradient elution, and the total run time was only 3 min. Data were analyzed and estimated using WinNonlin Professional version 5.1. With pharmacokinetic analysis, the estimated pharmacokinetic parameters (i.e. Cmax, area under the concentration–time curve (AUC) and t1/2), were Cmax = 776.06 ng/mL, AUC = 9473 ng/mL·h, t1/2 = 5.26 h for hesperetin and Cmax = 2910.6 ng/mL, AUC = 40607.9 ng/mL·h, t1/2 = 4.69 h for naringenin, respectively. In the present study, we have also valuated and clarified the effect of ZZW on small intestinal movement. It was found that ZZW can accelerate intestinal motility in mice and may hold a promising treatment for intestinal diseases. Copyright © 2012 John Wiley & Sons, Ltd.
Glycyrrhetinic Acid Exhibits Strong Inhibitory Effects Towards UDP‐Glucuronosyltransferase (UGT) 1A3 and 2B7
Authors: Huang Yin‐Peng , Cao Yun‐Feng , Fang Zhong‐Ze , Zhang Yan‐Yan , Hu Cui‐Min , Sun Xiao‐Yu , Yu Zhen‐Wen , Zhu Xu , Hong Mo , Yang Lu , Sun Hong‐Zhi
Published: November 2012

The aim of the present study is to evaluate the inhibitory effects of liver UDP‐glucuronosyltransferases (UGTs) by glycyrrhizic acid and glycyrrhetinic acid, which are the bioactive ingredients isolated from licorice. The results showed that glycyrrhetinic acid exhibited stronger inhibition towards all the tested UGT isoforms, indicating that the deglycosylation process played an important role in the inhibitory potential towards UGT isoforms. Furthermore, the inhibition kinetic type and parameters were determined for the inhibition of glycyrrhetinic acid towards UGT1A3 and UGT2B7. Data fitting using Dixon and Lineweaver‐Burk plots demonstrated that the inhibition of UGT1A3 and UGT2B7 by glycyrrhetinic acid was best fit to competitive and noncompetitive type, respectively. The second plot using the slopes from Lineweaver‐Burk plots versus glycyrrhetinic acid concentrations was employed to calculate the inhibition kinetic parameters (Ki), and the values were calculated to be 0.2 and 1.7 μM for UGT1A3 and UGT2B7, respectively. All these results remind us the possibility of UGT inhibition‐based herb–drug interaction. However, the explanation of these in vitro parameters should be paid more caution due to complicated factors, including the probe substrate‐dependent UGT inhibition behaviour, environmental factors affecting the abundance of herbs' ingredients, and individual difference of pharmacokinetic factors. Copyright © 2012 John Wiley & Sons, Ltd.
Anti‐Angiogenic Activity of Herba Epimedii on Zebrafish Embryos In Vivo and HUVECs In Vitro
Authors: Yu Xiaobin , Tong Yao , Han Xiao‐Qiang , Kwok Hin‐Fai , Yue Grace Gar‐Lee , Lau Clara Bik‐San , Ge Wei
Published: November 2012

Herba Epimedii, an herb commonly used in East Asian medicine, is commonly used for treatment of impotence, osteoporosis and many inflammatory conditions in traditional Chinese medicine. Recent studies revealed that Herba Epimedii also has anti‐tumor or anti‐cancer activities, which may possibly be mediated through anti‐angiogenesis. This study aims to examine and confirm the anti‐angiogenic activity in the herb using both in vivo and in vitro approaches. The 95% ethanol extract and four subsequent fractions (n‐hexane, ethyl acetate (EA), n‐butanol and aqueous fractions) of Herba Epimedii were tested on the zebrafish model by the quantitative assay for endogenous alkaline phosphatase; then, the active fraction was further tested on Tg(fli1a:EGFP)y1 zebrafish embryos and human umbilical vein endothelial cells (HUVECs) for the anti‐angiogenic effects. In addition, the action mechanism of Herba Epimedii was further investigated on wild‐type zebrafish embryos and HUVECs. The EA fraction showed anti‐angiogenic effects in both in vivo and in vitro models. Further experiments demonstrated that it might affect angiogenesis by acting on multiple molecular targets in zebrafish embryos and ERK signaling pathway in HUVECs. In conclusion, Herba Epimedii can inhibit angiogenesis, which may be the mechanism for its anti‐inflammatory, anti‐tumor and anti‐cancer actions. Copyright © 2012 John Wiley & Sons, Ltd.
Inhibition of Prostaglandin D2 Production by Trihydroxy Fatty Acids Isolated from Ulmus davidiana var. japonica
Authors: Choi Hyun Gyu , Park Yu Mi , Lu Yue , Chang Hyeun Wook , Na MinKyun , Lee Seung Ho
Published: November 2012

The stem and root barks of Ulmus davidiana var. japonica (Ulmaceae) have been used to treat inflammatory diseases including mastitis, rhinitis, sinusitis, and enteritis. In an ongoing study focused on the discovery of natural anti‐inflammatory compounds from natural products, a methanol extract of the stem and root barks of U. davidiana var. japonica showed anti‐inflammatory activities. Activity‐guided fractionation of the methanol extract yielded a new trihydroxy fatty acid, 9,12,13‐trihydroxyoctadeca‐10(Z),15(Z)‐dienoic acid (1), and a known compound, pinellic acid (2). These two trihydroxy fatty acids 1 and 2 inhibited prostaglandin D2 production with IC50 values of 25.8 and 40.8 μM, respectively. These results suggest that 9,12,13‐trihydroxyoctadeca‐10(Z),15(Z)‐dienoic acid (1) and pinellic acid (2) are among the anti‐inflammatory principles in this medicinal plant. Copyright © 2012 John Wiley & Sons, Ltd.
The effective density of small ice particles obtained from in situ aircraft observations of mid‐latitude cirrus
Authors: Cotton R. J. , Field P. R. , Ulanowski Z. , Kaye P. H. , Hirst E. , Greenaway R. S. , Crawford I. , Crosier J. , Dorsey J.
Published: November 2012

The effective ice‐particle density, parametrized through a mass–dimension relation, is widely used in ice microphysical schemes for weather and climate models. In this study, we use aircraft‐based observations in mid‐latitude cirrus taken during the Constrain field programme in 2010. The low temperatures and a humidity often close to ice saturation meant that the typical ice particles observed were small (maximum dimension 20–800 µm) and ice water contents were low (0.001–0.05 g m−3). Two new instruments are included in this study: the Small Ice Detector Mark‐2 (SID‐2) and the deep‐cone Nevzorov Total Water Content probe. SID‐2 is a new single‐particle light‐scattering instrument and was used to identify and size small ice particles (10–150 µm). The deep‐cone Nevzorov probe is shown to be able to collect small ice masses with sufficient sensitivity. The focus of this article is on the effective density of small ice particles (both pristine ice crystals and small aggregates up to 600 µm maximum dimension). Due to instrument limitations in previous studies, the effective density of small ice particles is questionable.

Aircraft flights in six cirrus cases provided ice‐particle measurements throughout the depth of the cirrus. The particle size distribution (PSD) was mostly bimodal. The smaller ice‐crystal mode dominated the PSD near cloud top and the larger ice‐aggregate mode dominated near cloud base. A mass–dimension relation valid for both ice crystals and aggregates was found that provided a best fit to the observations. For small ice particles (less than 70 µm diameter) the density is constant (700 kg m−3), while for larger ice crystals or aggregates the mass–dimension relation is m(D) = 0.0257D2.0. These measurements allow testing of the diagnostic split between ice crystals and aggregates used in the Met Office Unified Model.
Robust controller design for infinite‐dimensional exosystems
Authors: Paunonen L. , Pohjolainen S.
Published: November 2012

In this paper, we consider robust output regulation of distributed parameter systems with infinite‐dimensional exosystems capable of generating polynomially growing signals. We design an observer‐based error feedback controller solving the control problem. The controller is chosen in such a way that it incorporates an internal model of the infinite‐dimensional exosystem. The remaining parameters of the controller are chosen to stabilize the closed‐loop system strongly. We also analyze the classes of signals generated by the exosystem. In particular, we explore the connection between the smoothness properties of the reference and disturbance signals and the strictness of the conditions required for the existence of a controller solving the robust output regulation problem. Copyright © 2012 John Wiley & Sons, Ltd.
Impossibility of finding any third family of server protocols integrating Byzantine quorum systems with threshold signature schemes
Authors: Lin Jingqiang , Liu Peng , Jing Jiwu , Wang Qiongxiao
Published: November 2012

To tolerate servers' Byzantine failures, a distributed storage service of self‐verifying data needs to make three security properties be Byzantine fault tolerant (BFT): data consistency, data availability, and confidentiality of the signing service's private key. Building such systems demands the integration of Byzantine quorum systems (BQSs), which only make data consistency and availability be BFT, and threshold signature schemes (TSSs), which only make confidentiality of the private key be BFT. Two families of valid TSS‐BQS systems (of which the server protocols carry all the design options) have been proposed in the literature. Motivated by the failures in finding a third family of valid server protocols, we study the reverse problem and formally prove that it is impossible to find any third family of valid TSS‐BQS systems. To obtain this proof, we develop a validity theory on server protocols of TSS‐BQS systems. It is shown that the only two families of valid server protocols, “predicted” (or deduced) by the validity theory, precisely match the existing protocols. Copyright © 2012 John Wiley & Sons, Ltd.
Effect of low current density electrochemical oxidation on the properties of carbon fiber‐reinforced epoxy resin composites
Authors: Qian Xin , Zhi Jianhai , Chen Liqun , Huang Jing , Zhang Yonggang
Published: November 2012

Changes in surface physicochemical structures of polyacrylonitrile‐based carbon fibers resulted from low current density electrochemical oxidation were monitored by scanning electron microscopy (SEM) and X‐ray photoelectron spectroscopy (XPS). The relationship between the interlaminar shear strength (ILSS) values of carbon fiber‐reinforced polymers (CFRPs) and carbon fiber surface chemistry including elemental ratios and the relative content of oxygen‐containing functional groups were researched. SEM results revealed that the electrochemical oxidation got rid of surface contaminants generated during the production process. XPS analysis showed that the relative contents of oxygen and nitrogen increased by 446% and 202%, respectively, after the electrochemical oxidation. Carbon fiber surface chemistry was of paramount importance to the interfacial properties of CFRPs. The higher the carbon fiber surface activity, the better the interfacial bonding was, and an increase in the acidic‐group contents was responsible for a higher ILSS value. However, when the current density increased to 1.0 A/m2, the interfacial bonding between carbon fiber and the epoxy resin became weak which led to the decline in ILSS values. Copyright © 2012 John Wiley & Sons, Ltd.
Network analysis of supply chain systems: A systematic review and future research
Authors: Bellamy Marcus A. , Basole Rahul C.
Published: November 2012

Supply chains are continuously evolving and adapting systems driven by complex sociotechnical interfirm interactions. Traditional engineering and operations management modeling approaches have primarily focused on technical issues and are not well suited to effectively capture the many complex structural and behavioral aspects of supply chain systems (SCSs). There is growing recognition by the supply chain community of the significant benefits a network analytic lens can provide to understand, design, and manage SCSs. We systematically review and analyze the relevant literature and, drawing on a multidisciplinary theoretical foundation, develop an integrative framework. Our framework identifies three distinct, but interdependent themes that characterize the study of SCSs: SCS network structure (i.e., system architecture), SCS network dynamics (i.e., system behavior), and SCS network strategy (i.e., system policy and control). We elaborate on these themes, review key findings, identify the current limitations and knowledge gaps, and discuss the fundamental benefits derived from adopting an integrated SCSs perspective. We conclude with future research directions for network analysis in SCS design and management, in particular, and complex enterprise systems, in general. ©2012 Wiley Periodicals, Inc. Syst Eng 16:
Separating the research question from the laboratory techniques: Advancing high‐school biology teachers' ability to ask research questions
Authors: Hasson Eilat , Yarden Anat
Published: November 2012

Inquiry is essentially a process in which research questions are asked and an attempt is made to find the answers. However, the formulation of operational research questions of the sort used in authentic scientific inquiry is not a trivial task. Here, we set out to explore the possible influence of separating the research question from the laboratory techniques used to try and answer this question on teachers' understanding of laboratory techniques and their ability to formulate research questions. We conducted a laboratory course in microbiology in which the laboratory techniques were presented in an explicit and generalized manner, in the context of specific research questions. During the course, teachers' understanding of laboratory techniques improved as reflected in their answers to exercises given throughout. In addition, teachers' ability to ask research questions, analyzed using Dillon's classification of research questions, also improved. When reflecting upon the course, some teachers attributed the change in their ability to ask research questions to their increased knowledge of techniques, whereas others did not. We conclude that to facilitate research‐question‐asking skills among teachers, they should be provided with knowledge of the relevant laboratory techniques in an explicit fashion. © 2012 Wiley Periodicals, Inc. J Res Sci Teach 49: 1296–1320, 2012