bluuebunny/crossref_metadata_2025 huggingface dataset:
Resonant optical transmission through hole‐arrays in metal films: physics and applications
Authors: Gordon R. , Brolo A.G. , Sinton D. , Kavanagh K.L.
Published: May 2009

Extraordinary optical transmission through an array of holes in a metal film was reported by Ebbesen and coworkers in 1998. Since that work there has been abundant research activity aimed at understanding the physics and at the development of the many applications associated with this phenomenon, hence the topic of this review. The study of hole‐arrays in a metal is not new – theoretical contributions on a small‐hole array date back to Lord Rayleigh's description of Wood's anomaly in 1907 and there has been considerable research on metal meshes and hole‐arrays since 1962. Bethe's theory, adapted to treat hole‐arrays, is the simplest theoretical description of the transmission resonance. Following a description of this basic theory, we present the research on the additional effects from variations in real metal properties at different wavelengths, film thickness, hole‐shape and lattice configuration. The many promising applications being developed using hole‐arrays are examined, including polarization control, filtering, switching, nonlinear optics, surface plasmon resonance sensing, surface‐enhanced fluorescence, surface‐enhanced Raman scattering, absorption spectroscopy, and quantum interactions. Finally, the various approaches, developments in hole‐array fabrication, and integration of hole‐arrays into devices are described.
Electric Field‐Aided Formation Combined with a Nanoimprinting Technique for Replicating a Plant Leaf
Authors: Kim Geun Hyung , Jeon Ho Jun , Yoon Hyeon
Published: May 2009

The surface of the taro plant leaf was replicated using a nanoimprinting technique (NIT) supplemented with an electric field. This field‐aided nanoimprinting method (FA‐NIT) consists of two steps: applying an electric field to a liquid polymer under the plant leaves and the curing process of the polymer with the applied electric field. An appropriate electric field was needed to induce the electrokinetic phenomena of a liquid polymer to obtain a good replicated surface. The roughness fabricated by the FA‐NIT was about 45% higher than the one prepared by NIT. The FA‐NIT method is a good supplementary technique to improve the quality of NIT.

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Tannins: Current knowledge of food sources, intake, bioavailability and biological effects
Authors: Serrano José , Puupponen‐Pimiä Riitta , Dauer Andreas , Aura Anna‐Marja , Saura‐Calixto Fulgencio
Published: May 2009

Tannins are a unique group of phenolic metabolites with molecular weights between 500 and 30 000 Da, which are widely distributed in almost all plant foods and beverages. Proanthocyanidins and hydrolysable tannins are the two major groups of these bioactive compounds, but complex tannins containing structural elements of both groups and specific tannins in marine brown algae have also been described. Most literature data on food tannins refer only to oligomeric compounds that are extracted with aqueous‐organic solvents, but a significant number of non‐extractable tannins are usually not mentioned in the literature. The biological effects of tannins usually depend on their grade of polymerisation and solubility. Highly polymerised tannins exhibit low bioaccessibility in the small intestine and low fermentability by colonic microflora. This review summarises a new approach to analysis of extractable and non‐extractable tannins, major food sources, and effects of storage and processing on tannin content and bioavailability. Biological properties such as antioxidant, antimicrobial and antiviral effects are also described. In addition, the role of tannins in diabetes mellitus has been discussed.
Runaway Reaction Kinetics for Emulsion Polymerization and its Consequences
Authors: Manders Lambertus G.
Published: May 2009

For industrial semi‐batch emulsion polymerization, it is difficult to predict the composition of the reactor contents during a runaway reaction since many recipes are involved and it actually may be a fault in the feeds to the reactor that leads to the runaway reaction, as a distributed control system cannot safely prevent wrong feeds. Therefore, in order to safeguard the reactor, very high kinetics need to be taken into account, as discussed theoretically as well as based on an example. Corresponding maximum temperature increase rates may be above 100 K · min−1. This needs to be taken into account when designing safety measures for emulsion polymerization reactions. As a result, large safety relief valves or rupture discs may need to be installed.

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Ex vivo diffusion tensor MRI reflects microscopic structural remodeling associated with aging and disease progression in normal and cardiomyopathic Syrian hamsters
Authors: Li Wen , Lu Ming , Banerjee Suhanti , Zhong Jia , Ye Allen , Molter Joseph , Yu Xin
Published: May 2009

Dilated cardiomyopathy (DCM) is a major cause of mortality and morbidity in cardiac patients. Aging is often an ignored etiology of pathological conditions. Quantification of DCM and aging associated cardiac structural remodeling is important in guiding and evaluating therapeutic interventions. Diffusion tensor magnetic resonance imaging (DTMRI) has recently been used for nondestructive characterization of three‐dimensional myofiber structure. In this study, we explored the potential of DTMRI in delineating microscopic structural remodeling in aging and DCM hearts. Six month (n = 10) and nine month old (n = 11) DCM (TO‐2) hamsters and their age‐matched controls (F1β) were characterized. Both aging and DCM hearts showed increased diffusivity and decreased diffusion anisotropy. DTMRI images of DCM hearts also revealed a subgroup of imaging pixels characterized by decreased radial diffusivity and increased FA. The location of these pixels showed qualitative agreement with regions of calcium deposition determined by X‐ray CT imaging. Histological analysis confirmed expanded extracellular space in aging and DCM hearts as well as substantial calcium deposition in DCM hearts. These results suggest that DTMRI may provide a noninvasive technique to delineate structural remodeling associated with aging and DCM progression at the tissue and cellular level without the use of an exogenous contrast agent. Copyright © 2009 John Wiley & Sons, Ltd.
Midpoint rule for variational integrators on Lie groups
Authors: Saccon Alessandro
Published: May 2009

The midpoint rule provides a standard method to obtain symmetric, symplectic, and second‐order accurate variational integrators for mechanical systems whose configuration manifold is the vector space ℝn. In this work, we discuss how to extend this rule to a generic finite‐dimensional Lie group G while retaining the same properties. We show that the function κG(g)=exp(½log(g)), g∈G plays a special role in the theory and, for G=SO(3), we give a compact formula to compute it. We also discuss sufficient conditions for the method to conserve momentum maps associated with left (or right) group actions.

As an example, the variational integrator obtained from the midpoint rule is applied to simulating rigid body dynamics. The resulting integrator is compared with state‐of‐the‐art symmetric and second‐order accurate integrators for rigid body motion. Copyright © 2009 John Wiley & Sons, Ltd.
Implementation of meshless LBIE method to the 2D non‐linear SG problem
Authors: Mirzaei Davoud , Dehghan Mehdi
Published: May 2009

In this paper the meshless local boundary integral equation (LBIE) method for numerically solving the non‐linear two‐dimensional sine‐Gordon (SG) equation is developed. The method is based on the LBIE with moving least‐squares (MLS) approximation. For the MLS, nodal points spread over the analyzed domain are utilized to approximate the interior and boundary variables. The approximation functions are constructed entirely using a set of scattered nodes, and no element or connectivity of the nodes is needed for either the interpolation or the integration purposes. A time‐stepping method is employed to deal with the time derivative and a simple predictor–corrector scheme is performed to eliminate the non‐linearity. A brief discussion is outlined for numerical integrations in the proposed algorithm. Some examples involving line and ring solitons are demonstrated and the conservation of energy in undamped SG equation is investigated. The final numerical results confirm the ability of method to deal with the unsteady non‐linear problems in large domains. Copyright © 2009 John Wiley & Sons, Ltd.
An efficient numerical method for computing the topological sensitivity of arbitrary‐shaped features in plate bending
Authors: Turevsky Inna , Gopalakrishnan Sankara Hari , Suresh Krishnan
Published: May 2009

The objective of this paper is to introduce an efficient numerical scheme to compute the topological sensitivity (TS) of arbitrary‐shaped features in plate bending. The proposed method captures the first‐order change in quantities of interest (example: plate compliance) when an arbitrary‐shaped feature is created within a plate. Both the theory and algorithms are provided to rapidly compute the feature‐specific TS for the classic Kirchhoff–Love plate models.

An important application of the proposed method is in design exploration/optimization wherein a designer can explore the impact of including plate features, without recourse to repeated finite element analysis. The proposed method is illustrated and validated through numerical experiments. Copyright © 2009 John Wiley & Sons, Ltd.
Methods to improve reliability of video‐recorded behavioral data
Authors: Haidet Kim Kopenhaver , Tate Judith , Divirgilio‐Thomas Dana , Kolanowski Ann , Happ Mary Beth
Published: May 2009

Behavioral observation is a fundamental component of nursing practice and a primary source of clinical research data. The use of video technology in behavioral research offers important advantages to nurse scientists in assessing complex behaviors and relationships between behaviors. The appeal of using this method should be balanced, however, by an informed approach to reliability issues. In this article, we focus on factors that influence reliability, such as the use of sensitizing sessions to minimize participant reactivity and the importance of training protocols for video coders. In addition, we discuss data quality, the selection and use of observational tools, calculating reliability coefficients, and coding considerations for special populations based on our collective experiences across three different populations and settings. © 2009 Wiley Periodicals, Inc. Res Nurs Health 32: 465–474, 2009
Sporadic childhood Burkitt lymphoma incidence in the United States during 1992–2005
Authors: Mbulaiteye Sam M. , Biggar Robert J. , Bhatia Kishor , Linet Martha S. , Devesa Susan S.
Published: May 2009

Background

The risk factors and co‐factors for sporadic childhood BL are unknown. We investigated demographic and age‐specific characteristics of childhood BL (0–14 years) in the U.S.

Procedure

BL age‐standardized incidence rates (2000 U.S. standard population), were calculated using data obtained from 12 registries in the NCI's Surveillance, Epidemiology, and End Results program for cases diagnosed from 1992 to 2005. Incidence rate ratios and 95% confidence intervals (95% CI) were calculated by gender, age‐group, race, ethnicity, calendar‐year period, and registry.

Results

Of 296 cases identified, 56% were diagnosed in lymph nodes, 21% in abdominal organs, not including retroperitoneal lymph nodes, 14% were Burkitt cell leukemia, and 9% on face/head structures. The male‐to‐female case ratio was highest for facial/head tumors (25:1) and lowest for Burkitt cell leukemia (1.6:1). BL incidence rate was 2.5 (95% CI 2.3–2.8) cases per million person‐years and was higher among boys than girls (3.9 vs. 1.1, P < 0.001) and higher among Whites and Asians/Pacific Islanders than among Blacks (2.8 and 2.9 vs. 1.2, respectively, P < 0.001). By ethnicity, BL incidence was higher among non‐Hispanic Whites than Hispanic Whites (3.2 vs. 2.0, P = 0.002). Age‐specific incidence rate for BL peaked by age 3–5 years (3.4 cases per million), then stabilized or declined with increasing age, but it did not vary with calendar‐year or registry area.

Conclusions

Our results indicate that early childhood exposures, male‐sex, and White race may be risk factors for sporadic childhood BL in the United States. Pediatr Blood Cancer 2009;53:366–370. Published 2009 Wiley‐Liss, Inc.
Secondary acute myeloid leukemia after etoposide therapy for haemophagocytic lymphohistiocytosis
Authors: RamaChandran Shanti , Ariffin Hany
Published: May 2009

Haemophagocytic lymphohistiocytosis (HLH) is an uncommon disease with a high fatality rate. Etoposide is an important component of current HLH treatment regimes. Two patients with HLH developed etoposide‐related secondary acute myeloid leukemia (sAML) following therapy for HLH. Etoposide, an epipodophyllotoxin, is a topoisomerase II inhibitor that interacts with DNA to potentiate leukaemogenesis. The risk of developing sAML is estimated to be between 1% and 5%, 2–20 years after exposure to etoposide but may also be related to cumulative drug doses, treatment schedules, host factors and co‐administration of other antineoplastic agents. Pediatr Blood Cancer 2009;53:488–490. © 2009 Wiley‐Liss, Inc.
Hemophagocytic lymphohistiocytosis and Kawasaki disease: Combined manifestation and differential diagnosis
Authors: Titze Ulf , Janka Gritta , Schneider E. Marion , Prall Friedrich , Haffner Dieter , Classen Carl Friedrich
Published: May 2009

Both hemophagocytic lymphohistiocytosis (HLH) and Kawasaki disease (KD) are diagnosed in patients with prolonged resistant fever by using a scoring system. Concurrent manifestation of both conditions has been reported previously. We describe an infant of 7 weeks whose condition fulfilled the criteria of HLH, but who, after clinical response to treatment, suddenly died from a myocardial infarction at 11 weeks. Post‐mortem examination revealed a previously unknown coronary arteritis typical for KD. Since it is difficult to distinguish between KD and HLH, both diseases should be considered in young children with overlapping symptoms. Repeated echocardiograms may be helpful in these cases. Pediatr Blood Cancer 2009;53:493–495. © 2009 Wiley‐Liss, Inc.
Continuous subcutaneous insulin infusion: experience from a large specialist service
Authors: Chellamuthu P , Lawrence IG , Kitchener D , McNally PG , Gregory R , Jackson S , Kong M‐F , Jarvis J , Davies MJ
Published: May 2009

The National Institute for Health and Clinical Excellence issued guidelines on continuous subcutaneous insulin infusion (CSII) in 2003 and has recently updated them. We present the findings of a retrospective study on CSII in a tertiary teaching hospital.

Data were analysed on 85 patients established on CSII. The mean follow up was 24 months, 70% were female and the mean age was 40 years. Eighty‐two patients (96.5%) had type 1 diabetes, the mean duration of diabetes being 23 years, and NICE guidelines were followed for initiation in 78%. Patient satisfaction was assessed by Likert scale (‐3 to + 3) questionnaire.

On CSII there was an improvement in HbA1c (mean [SD] 9.4[1.9] vs 8.6[1.5]%; [p<0.01]), with no significant change in weight. Severe hypoglycaemia decreased from 0.85 episodes/patient‐year to 0.08/patient‐year without an increase in diabetic ketoacidosis (0.20/patient‐year vs 0.09/patient‐year). Mean basal insulin requirement fell from 31(25) to 22(16) units (p<0.01). Thirty‐five out of the 85 patients had undertaken a DAFNE (Dose Adjustment For Normal Eating) course. After DAFNE, mean HbA1c fell from 9.2 to 8.9% (p<0.05), and then to 8.5% (p<0.05) after pump therapy. The response rate to the satisfaction questionnaire was 92%. Patients were happier on the pump compared to their previous treatment (mean score 2.5[2.3‐2.7 95% CI]). In the cohort of patients established on pump therapy, there was a significant improvement in glycaemic control, with an accompanying reduction in severe hypoglycaemia.

Insulin pump therapy improves glycaemic control further in DAFNE graduates with no increase in severe hypoglycaemia. Patients were satisfied with pump therapy. Copyright ©2009 John Wiley & Sons, Ltd.
Post‐prandial glucose levels following three methods of insulin bolusing A study in adolescent girls and in comparison with girls without diabetes
Authors: Olinder A Lindholm , Runefors J , Smide B , Kernell A
Published: May 2009

The aims of this study were to assess whether one method of insulin bolusing was superior to two others in managing two pasta meals, and to compare the glucose levels with those of females without diabetes.

Fifteen continuous subcutaneous insulin infusion (CSII)‐treated adolescent females and 10 adolescent females without diabetes consumed two pasta meals with different fat contents. The plasma glucose (p‐glucose) values were followed using capillary measurement and continuous glucose monitoring (CGMS) until three hours after the meal. The CSII‐treated females received the same insulin dose at every occasion as: (1) normal bolus; (2) dual‐wave bolus – 60% of the dose as normal bolus and 40% over one hour; and (3) square‐wave bolus – a prolonged dose over one hour.

No differences were found in p‐glucose peak or AUC between the bolus methods after either of the meals. There was a difference in p‐glucose increase at one time point after the less fat meal; after 60 minutes the increase was greater with a square‐wave bolus (Friedman's test p <0.02). Forty‐eight percent of the measurements among the diabetes adolescents showed post‐prandial p‐glucose levels ≤ 10mmol/L. Females without diabetes had earlier and lower p‐glucose peak and smaller AUC.

It was concluded that there were no overall differences in p‐glucose excursions between different methods of bolusing for these adolescent females after these meals. A square‐wave bolus may be less favourable with a less fatty pasta meal, giving a higher p‐glucose increase. It was possible to achieve normoglycaemic post‐prandial p‐glucose levels among adolescents with diabetes. Copyright © 2009 John Wiley & Sons.
Socioeconomic conditions among long‐term gynaecological cancer survivors—a population‐based case–control study
Authors: Platou Toril Forbord , Skjeldestad Finn Egil , Rannestad Toril
Published: May 2009

Background: The population of gynaecological cancer survivors is growing, yet little is known about the effects of cancer and treatment on socioeconomic conditions well beyond the completion of therapy. The aim of this study was to investigate the socioeconomic conditions in long‐term survivors of gynaecological cancer compared with a representative group of women from the general population.

Material and methods: The study comprises women aged 32–75 residing in central part of Norway and who were treated as primary cases of gynaecological cancer at the University Hospital in Trondheim, Norway (n=160), and a control group from the general population (n=493). All analyses were done by χ2 test and logistic regression.

Results: Gynaecological cancer survivors scored lower on a Socioeconomic Condition Index than the control group. They had on the average a complete remission period of 12 years. Compared with the control group, they were more often disabled (p<0.01) and had lower annual household income (p<0.01). No difference was detected between the groups in ability to pay bills. More cases than controls had experienced problems assigning personal insurance (p<0.03).

Conclusion: Long‐term gynaecological cancer survivors lived under poorer socioeconomic conditions, were more often disabled and had lower annual household income than the women in the control group, whereas no difference in ability to pay bills were found between the groups. In spite of poorer socioeconomic conditions, the gynaecological cancer survivors seem to adapt well to their financial situation. Copyright © 2009 John Wiley & Sons, Ltd.
A model for the interaction between NF‐kappa‐B and ASPP2 suggests an I‐kappa‐B‐like binding mechanism
Authors: Benyamini Hadar , Leonov Hadas , Rotem Shahar , Katz Chen , Arkin Isaiah T. , Friedler Assaf
Published: May 2009

We used computational methods to study the interaction between two key proteins in apoptosis regulation: the transcription factor NF‐κ‐B (NFκB) and the proapoptotic protein ASPP2. The C‐terminus of ASPP2 contains ankyrin repeats and SH3 domains (ASPP2ANK‐SH3) that mediate interactions with numerous apoptosis‐related proteins, including the p65 subunit of NFκB (NFκBp65). Using peptide‐based methods, we have recently identified the interaction sites between NFκBp65 and ASPP2ANK‐SH3 (Rotem et al., J Biol Chem 283, 18990–18999). Here we conducted a computational study of protein docking and molecular dynamics to obtain a structural model of the complex between the full length proteins and propose a mechanism for the interaction. We found that ASPP2ANK‐SH3 binds two sites in NFκBp65, at residues 236–253 and 293–313 that contain the nuclear localization signal (NLS). These sites also mediate the binding of NFκB to its natural inhibitor IκB, which also contains ankyrin repeats. Alignment of the ankyrin repeats of ASPP2ANK‐SH3 and IκB revealed that both proteins share highly similar interfaces at their binding sites to NFκB. Protein docking of ASPP2ANK‐SH3 and NFκBp65, as well as molecular dynamics simulations of the proteins, provided structural models of the complex that are energetically similar to the NFκB‐IκB determined structure. Our results show that ASPP2ANK‐SH3 binds NFκBp65 in a similar manner to its natural inhibitor IκB, suggesting a possible novel role for ASPP2 as an NFκB inhibitor. Proteins 2009. © 2009 Wiley‐Liss, Inc.
Calcineurin regulatory subunit B is a unique calcium sensor that regulates calcineurin in both calcium‐dependent and calcium‐independent manner
Authors: Li Jing , Jia ZhiGuang , Zhou WenChang , Wei Qun
Published: May 2009

Calcineurin subunit B (CNB), a regulatory subunit of calcineurin, is a member of EF‐hand calcium (Ca2+)‐binding protein superfamily. In this study, we performed phosphatase activity, pull‐down, and circular dichroism analyses, which shows Ca2+‐free CNB (apo‐CNB) is able to bind CNA (Calcineurin subunit A) and regulate its phosphatase activity, albeit to a lesser extent than Ca2+‐saturated CNB (holo‐CNB). This is supported by subsequent molecular dynamics (MD) simulations which aimed to examine calcium‐induced conformational changes of CNB, using both holo‐CNB and apo‐CNB. Based on the trajectories of MD, we found that there were no drastic changes between holo‐CNB and apo‐CNB. The modest differences seen are mainly reflected in the interhelical angles of the four EF‐hand motifs and solvent accessible surface area of the hydrophobic groove which is responsible for CNA binding. Interestingly, this hydrophobic groove was largely retained in both holo‐CNB and apo‐CNB. Comparative analyses show that the calcium‐induced conformational change in CNB is remarkably different from that of the two prototypical EF‐hand calcium‐binding proteins, namely, calmodulin and recoverin. This is the first time that CNB is shown to activate CNA in the absence of Ca2+. Proteins 2009. © 2009 Wiley‐Liss, Inc.
Thermodynamics of zinc binding to hepatitis C virus NS3 protease: A folding by binding event
Authors: Abian Olga , Neira Jose Luis , Velazquez‐Campoy Adrian
Published: May 2009

The hepatitis C virus (HCV) nonstructural protein 3 (NS3) protease is responsible for the processing of the non‐structural region of the viral precursor polyprotein in infected hepatic cells. HCV NS3 is a zinc‐dependent serine protease. The zinc ion, which is bound far away from the active site and considered to have a structural role, is essential for the structural integrity of the protein; furthermore, the ion is required for the hydrolytic activity. Consequently, the NS3 zinc binding site has been considered for a long time as a possible target for drug discovery. As a first step towards this goal, the energetics of the NS3‐zinc interaction and its effect on the NS3 conformation must be established and discussed. The thermodynamic characterization of zinc binding to NS3 protease by isothermal titration calorimetry and spectroscopy is presented here. Spectroscopic and calorimetric results suggest that a considerable conformational change in the protein is coupled to zinc binding. The energetics of the conformational change is comparable to that of the folding of a protein of similar size. Therefore, zinc binding to NS3 protease can be considered as a “folding by binding” event. Proteins 2009. © 2009 Wiley‐Liss, Inc.
Insight into the substrate length restriction of M32 carboxypeptidases: Characterization of two distinct subfamilies
Authors: Lee Marianne M. , Isaza Clara E. , White James D. , Chen Rita P.‐Y. , Liang George F.‐C. , He Hannah T.‐F. , Chan Sunney I. , Chan Michael K.
Published: May 2009

M32 carboxypeptidases are a distinct family of HEXXH metalloproteases whose structures exhibit a narrow substrate groove that is blocked at one end. Structural alignments with other HEXXH metalloprotease‐peptide complexes suggested an orientation in which the substrate is directed towards the back of the groove. This led us to hypothesize, and subsequently confirm that the maximum substrate length for M32 carboxypeptidases is restricted. Structural and sequence analyses implicate a highly conserved Arg at the back of the groove as being critical for this length restriction. However, the Thermus thermophilus and Bacillus subtilis M32 members lack this conserved Arg. Herein, we present the biochemical and structural characterization of these two proteins. Our findings support the important role of the conserved Arg in maintaining the length restriction, and reveal a proline‐rich loop as an alternate blocking strategy. Based on our results, we propose that M32 carboxypeptidases from Bacilli belong to a separate subfamily. Proteins 2009. © 2009 Wiley‐Liss, Inc.
A novel audit model for assessing quality in non‐regulated research
Authors: Volsen S. G. , Masson M. M.
Published: May 2009

The need for Quality standards in non‐regulated research is a matter of considerable current debate. Whilst a number of such guidelines have been developed over recent years, their successful implementation remains a challenge to all. In order to assess whether research standards are indeed improving on the bench following the instigation of such a quality system, a question posed by both senior management and scientists alike, an independent compliance programme is required. However, given the lack of predicate rules, naivety to audit process and general sensitivity to external scrutiny within the scientific ranks, then work in this ‘Grey Area’ generates high exposure for the conventional GLP, GCP or GMP auditor. We have developed, tried, and tested a highly effective, novel audit model for assessing the quality of non‐regulated research. This simple system can be applied successfully irrespective of scientific discipline or field. Whilst common principles will always apply during any quality system audit, the refinements and idiosyncrasies we describe here will, as we have found, help underpin success. Our intentional assumption is that this is a first time endeavour for the quality professional. Copyright © 2009 John Wiley & Sons, Ltd.
Quantitative approach to the understanding of catalytic effect of metal oxides on the desorption reaction of MgH2
Authors: Hirate H. , Saito Y. , Nakaya I. , Sawai H. , Shinzato Y. , Yukawa H. , Morinaga M. , Baba T. , Nakai H.
Published: May 2009

The hydrogen desorption reaction of magnesium hydride (MgH2), MgH2→Mg+H2, is accelerated by mixing catalytic metal oxides (e.g., Nb2O5). This catalytic effect of metal oxides, MxOy, is theoretically estimated in a quantitative way using atomization energy concept. The atomization energies, ΔEM for metal ion and ΔEO for oxide ion in various metal oxides are evaluated using the energy density analysis of the total energy. It is shown that the hydrogen desorption rate increases monotonously with increasing y ×ΔEO values of metal oxides. This indicates that the oxide ion in MxOy interacts mainly with hydrogen atoms in MgH2. The y × ΔEO value is a measure of the magnitude of the OH interaction operating between MxOy and MgH2, and hence, it is indeed a good parameter to show the catalytic activities of metal oxides. This approach is useful for the analysis of other catalyst and catalytic reactions. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
High‐resolution soft X‐ray spectral analysis in the CK region of titanium carbide using the DV‐Xα molecular orbital method
Authors: Shimomura Kenta , Muramatsu Yasuji , Denlinger Jonathan D. , Gullikson Eric M.
Published: May 2009

We used the discrete variational (DV) ‐Xα method to analyze the high‐resolution soft X‐ray emission and absorption spectra in the CK region of titanium carbide (TiC). The spectral profiles of the X‐ray emission and absorption can be successfully reproduced by the occupied and unoccupied density of states (DOS), respectively, in the C2p orbitals of the center carbon atoms in a Ti62C63 cluster model, suggesting that the center carbon atom in a large cluster model expanded to the cubic‐structured 53 (= 125) atoms provides sufficient DOS for the X‐ray spectral analysis of rock‐salt structured metal carbides. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Calculation of the electronic structure of AmO2 and Pr6O11 for XANES analysis with redox property
Authors: Suzuki Chikashi , Nishi Tsuyoshi , Nakada Masami , Akabori Mitsuo , Hirata Masaru , Kaji Yoshiyuki
Published: May 2009

We calculated X‐ray absorption near‐edge structure (XANES) of Am LIII of AmO2 and Pr LIII of Pr6O11 using the relativistic discrete‐variational (DV)‐Xα method based on the Dirac–Slater method, and compared it with the experimental spectra. These spectra were calculated on a model of AmO2 ([AmO8]12−) and Pr6O11 ([PrO8]12−). In spite of using small cluster models, the calculated spectra were in good agreement with the experiment ones. Besides, we calculated the electronic structure of AmO2 and Pr6O11 to analyze the peak structures of XANES. From this calculation, it was found that O s, p, and f components had influence on the specific peak structures but that O d component had influence on various peak structures for AmO2 and Pr6O11. From this result, it was suggested that the change of the electronic structure of actinide 6d and O d or f was important for actinide LIII XANES corresponding to oxygen to metal ratio in the oxide nuclear fuel. On the basis of these results, we calculated the fine structures of densities of states and the transition energy from the HOMO to the white line of AmO2, UO2, and Pr6O11 and investigated redox properties of Am and U in the oxide nuclear fuel with the evaluation of validity of Pr as simulant materials of Am. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Simultaneous determination of parabens, triclosan and triclocarban in water by liquid chromatography/electrospray ionisation tandem mass spectrometry
Authors: González‐Mariño Iria , Quintana José Benito , Rodríguez Isaac , Cela Rafael
Published: May 2009

A method for the determination of several household biocides in water by liquid chromatography/electrospray ionisation tandem mass spectrometry (LC/ESI‐MS/MS) is presented. It permits the simultaneous determination of triclosan (TCS), triclocarban (TCC) and seven parabens, including the distinction between branched and linear isomers of propyl (i‐PrP and n‐PrP) and butyl parabens (i‐BuP and n‐BuP). Prior to LC/MS/MS, analytes are preconcentrated by solid‐phase extraction (SPE) on Oasis HLB (60 mg) cartridges at natural sample pH and subsequently eluted with 4 mL of methanol. This simple SPE procedure provides extraction recoveries above 85% except for raw wastewater, where it falls to 65% for TCC. The performance of the method was tested with two triple‐quadrupole LC/MS instruments from a low/mid and mid/high market range: a Varian 1200L and an API‐4000. The latter system provided between 3 and 80 times lower limits of quantification (LOQs) than the first one, in the 0.08–0.44 ng/L range for surface water. Moreover, a comparison of matrix effects on both instruments showed a very different behaviour, particularly in the case of parabens. For these compounds signal suppression was observed in the 1200L instrument and signal enhancement with the 4000 instrument. As a result, different calibration approaches were chosen for them and this pointed to the need of matrix effect re‐evaluation in method transfer between different LC/MS systems. The application of the method to real samples showed the ubiquity of methyl paraben (MeP) and n‐PrP (at the 1–6 µg/L in raw wastewater) and the coexistence of i‐BuP and n‐BuP at similar levels (ca. 100–200 ng/L in raw wastewater). Copyright © 2009 John Wiley & Sons, Ltd.
Determination of urine melamine by validated isotopic ultra‐performance liquid chromatography/tandem mass spectrometry
Authors: Cheng Wei‐Chih , Chen Shu‐Kong , Lin Tien‐Jen , Wang I‐Jen , Kao Ya‐Min , Shih Daniel Yang‐Chih
Published: May 2009

Little is known about melamine (MEL) analysis in children's urine. In this study, an isotopic ultra‐performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) method was developed and systematically validated for the analysis of MEL in urine. The method is easily performed and comprises acidification, solid‐phase extraction (SPE) and UPLC/MS/MS analysis.13C3N3(15NH2)3was used as the internal standard (IS) for calibration. Transition ionsm/z127 > 85 of MEL andm/z133 > 89 of the IS were used for quantification andm/z127 > 68 of MEL was used for quantitative confirmation. Recovery and precision were assessed to guarantee the applicability of the method. The limit of quantification (LOQ) was 0.01 µg/mL while the calculated method detection limit was 0.006 µg/mL. The mean recoveries ranged from 96–99%. The method was then applied to analyze urine samples from children who had potentially consumed MEL‐tainted dairy products during screening in Taiwan. Ten nephrolithiasis cases and 20 age‐ and gender‐matched controls were selected for this study. Three out of the 10 nephrolithiasis cases had elevated levels of MEL. Comparatively, twenty age‐ and gender‐matched non‐nephrolithiasis controls consuming Taiwan brand milk powder all showed MEL levels lower than the detection limit except for two children with background levels of 0.02 µg/mL. The background level in these children urine samples was established by UPLC/MS/MS analysis. Positive results of urine MEL tests might be associated with nephrolithiasis in these candidates. Measurement of urine MEL concentration can be helpful in confirming MEL‐related nephrolithiasis, but its clinical application needs further clarification. Copyright © 2009 John Wiley & Sons, Ltd.
Unknown input reconstruction for LPV systems
Authors: Kulcsár Balázs , Bokor József , Shinar Josef
Published: May 2009

Detection and invariant subspaces of unknown inputs' signals for linear parameter‐varying systems are examined in the paper. For a class of nonlinear system like this, the effect of unmeasured signals in parameter‐varying measurement equation at the plant output is investigated.

The main contributions of the paper are the parameter‐varying extension of the pseudo‐actuation of the possible and generic unknown sensor signal and the proposition of parameter‐dependent similarity transformation. The general parameter‐varying measurement equation is casted into a parameter‐independent form by the similarity transformation, if any. Moreover, it showed that the nonlinear state transformation does not modify the output subspace spanned by the equivalent pseudo‐actuator directions.

The proposed methods are illustrated by a numerical example. Copyright © 2009 John Wiley & Sons, Ltd.
Principal component analysis and dimensional analysis as materials informatics tools to reduce dimensionality in materials science and engineering
Authors: Rajan Krishna , Suh Changwon , Mendez Patricio F.
Published: May 2009

In engineering design, we are constantly faced with the need to describe the behavior of complex engineered systems for which there is no closed‐form solution. There is rarely a single multiscale theory or experiment that can meaningfully and accurately capture such information primarily due to the inherently multivariate nature of the variables influencing materials behavior. Seeking structure‐property relationships is an accepted paradigm in materials science, yet these relationships are often not linear, and so the challenge is to seek patterns among multiple length and time scales. In this paper, we present two separate but complementary examples of addressing the issue of high‐dimensional data in materials science in the spirit of the intellectual focus of this new journal. The first example uses principal component analysis and the second example uses statistical analysis coupled to dimensional analysis. Copyright © 2009 Wiley Periodicals, Inc., A Wiley Company
Doppler flow velocity waveforms in the embryonic chicken heart at developmental stages corresponding to 5–8 weeks of human gestation
Authors: Oosterbaan A. M. , Ursem N. T. C. , Struijk P. C. , Bosch J. G. , van der Steen A. F. W. , Steegers E. A. P.
Published: May 2009

Objectives

To obtain Doppler velocity waveforms from the early embryonic chicken heart by means of ultrasound biomicroscopy and to compare these waveforms at different stages of embryonic development.

Methods

We collected cardiac waveforms using high‐frequency Doppler ultrasound with a 55‐MHz transducer at Hamburger–Hamilton (HH) stages 18, 21 and 23, which are comparable to humans at 5 to 8 weeks of gestation. Waveforms were obtained at the inflow tract, the primitive left ventricle, the primitive right ventricle and at the outflow tract in 10 different embryos per stage. M‐mode recordings were collected to study opening and closure of the cushions. By exploring the temporal relationship between the waveforms, using a secondary Doppler device, cardiac cycle events were outlined.

Results

Our results demonstrate that stage‐ and location‐dependent intracardiac blood flow velocity waveforms can be obtained in the chicken embryo. The blood flow profiles assessed at the four locations in the embryonic heart demonstrated an increase in peak velocity with advancing developmental stage. In the primitive ventricle the ‘passive’ (P) filling peak decreased whereas the ‘active’ (A) filling peak increased, resulting in a decrease in P to A ratio with advancing developmental stage. M‐mode recordings demonstrated that the fractional closure time of the atrioventricular cushions increased from 20% at stage HH 18 to 60% at stage HH 23.

Conclusion

High‐frequency ultrasound biomicroscopy can be used to define flow velocity waveforms in the embryonic chicken heart. This may contribute to an understanding of Doppler signals derived from valveless embryonic human hearts at 5 to 8 weeks of gestation, prior to septation. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
Tomographic ultrasound imaging of the pelvic floor: which levels matter most?
Authors: Dietz H. P. , Shek K. L.
Published: May 2009

Objectives

Tomographic ultrasound imaging has greatly simplified pelvic floor assessment. Abnormalities of the insertion of the levator ani can be documented in a single frame. In this study we aimed to determine which levels of the levator hiatus are associated with alterations in ultrasound parameters of pelvic organ support.

Methods

This was a subanalysis of a study conducted in 296 women seen before and after their first delivery. We analyzed postpartum changes in bladder neck descent and hiatal area as indicators of altered pelvic organ support. Tomographic ultrasound examination was performed on volumes obtained at maximal pelvic floor muscle contraction, at 2.5‐mm slice intervals, from 5 mm below to 12.5 mm above the plane of minimal hiatal dimensions.

Results

Two hundred and eight recruits (70%) returned for a postnatal appointment. Of these, 130 had delivered vaginally and 26 (20%) were diagnosed with an avulsion injury. An abnormality in slices 3–8 was associated with increased bladder neck descent postpartum (P = 0.038 to P = 0.001) and increased hiatal area on Valsalva maneuver (P = 0.029 to P < 0.001). This was not the case for the two most distal slices.

Conclusions

We found no association between levator ani defects observed on tomographic ultrasound imaging below the plane of minimal hiatal dimensions and indices of increased hiatal distension or bladder neck descent on Valsalva maneuver. This implies that defects observed below this plane are either irrelevant for pelvic organ support or artifactual. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
Thirty years later: enrichment practices for captive mammals
Authors: Hoy Julia M. , Murray Peter J. , Tribe Andrew
Published: May 2009

Environmental enrichment of captive mammals has been steadily evolving over the past thirty years. For this process to continue, it is first necessary to define current enrichment practices and then identify the factors that limit enhancing the quality and quantity of enrichment, as well as the evaluation of its effectiveness. With the objective of obtaining this information, an international multi‐institutional questionnaire survey was conducted with individuals working with zoo‐housed mammals. Results of the survey showed that regardless of how important different types of enrichment were perceived to be, if providing them was particularly time‐consuming, they were not made available to captive mammals as frequently as those requiring less staff time and effort. The groups of mammals provided with enrichment most frequently received it on average fewer than four times per day, resulting in less than two hours per day spent by each animal care staff member on tasks related to enrichment. The time required for staff to complete other husbandry tasks was the factor most limiting the implementation and evaluation of enrichment. The majority of survey respondents agreed that they would provide more enrichment and carry out more evaluation of enrichment if it was manageable to do so. The results of this study support the need for greater quantity, variety, frequency, and evaluation of enrichment provided to captive mammals housed in zoos without impinging on available staff time. Zoo Biol 29:303–316, 2010. © 2009 Wiley‐Liss, Inc.
Use of snake‐cage polyelectrolytes for purifying glycerine
Authors: Hatch Melvin J. , Smith Hugh B.
Published: May 2009

Amphoteric snake‐cage resins were applied successfully to separate sodium chloride from glycerine. Good separations were obtained by the ion‐retardation method at glycerine feed concentrations as high as 50% and at flow rates as fast as 1 gal. per square foot per minute in beds which were 3 ft. deep or less. Glycerine product was obtained at concentrations of 20舑35%; glycerine loss was only 1% and removal of the sodium chloride 90% or more. Thus greater resin productivity and higher product concentration resulted that in comparative ion‐exclusion experiments. As a results, the calculated capital investment was much less for an ion‐retardation plant for purifying glycerine. The calculated operating costs were slightly less.
Bland undenatured soybean flakes by alcohol washing and flash desolventizing
Authors: Mustakas G. C. , Kirk L. D. , Griffin E. L.
Published: May 2009

The conditions for removing the beany and bitter flavor from defatted soybean meal with ethanol and isopropyl alcohol were investigated. In the presence of alcohols, soybean protein is extremely sensitive to denaturation when temperature, moisture, and residence time are increased. If protein is to be isolated in good yield and quality, retention of the original, high watersolubility is important, and denaturation must be kept to a minimum.

Defatted soybean flakes were successfully debittered by countereurrent washing with aqueous alcohols on a pilot‐plant scale, and the entrained solvent was recovered by flash desolventizing without excessive denaturation of protein. Effective debittering was obtained with 95 volume percentage ethanol and 91 volume percentage isopropyl alcohol whereas satisfactory flavor was not obtained with absolute ethanol. The solubility of the nitrogenous compounds in the meal product (Nitrogen Solubility Index舒NSI=water‐soluble nitrogenȕ100ɇ total nitrogen) was maintained at 68 NSI, or higher, regardless of the solvent system or conditions used when starting with 80 NSI defatted flakes. Residual alcohol in the desolventized products was reduced to 1舑2% with the aqueous alcohol system and to less than 1% for the absolute alcohol system. Lower residual values can be obtained by recycling the material through the desolventizing unit. The desolventizing system described is simple, low in cost, and should be useful in any process requiring the rapid removal of solvent from residual solids where heat‐sensitive constituents are present.
An hypothesis for the mechanism of the heme catalyzed lipid oxidation in animal tissues
Authors: Tarladgis Basil G.
Published: May 2009

The catalytic activity of the heme compounds on lipid oxidation in muscle tissues has been reviewed. Evidence from experiments found in the literature, and unpublished studies in this laboratory on meats and fishery products, lead to the conclusion that the ferric heme compounds initiate lipid oxidation, while the ferrous heme compounds are inactive in the absence of preformed peroxides. The latter are decomposed by both types of heme compounds, but by a different mechanism.

A comprehensive mechanism of the different catalytic activities of the various heme compounds has been presented, based on both experimental evidence and theoretical considerations.
The effect of calcium ions on carbon suspensions
Authors: Peper H. , Rosano H. L.
Published: May 2009

A high degree of dispersion of carbon black in water is obtained only in the presence of adsorbing long‐chain, amphipathic molecules. Calcium ions flocculate these dispersions, but agglomeration can be prevented if anionic detergents are adsorbed on the carbon. Fine dispersions of carbon coated with a fatty acid or alcohol were maintained in the presence of calcium ions with detergents which coadsorb with the acid or alcohol monolayer. The significance of these results in regard to detergency theory is discussed.
The influence of moisture content and cooking on the screw pressing and prepressing of corn oil from corn germ
Authors: Moreau Robert A. , Johnston David B. , Hicks Kevin B.
Published: May 2009

Samples of corn germ were obtained from a commercial corn wet mill (factory dried to about 3% moisture) and a commerical corn dry mill (undried, produced in the mill with about 13% moisture). The germ samples (200 g each) were cooked for various times in either a conventional oven at 180°C or a microwave oven at 1500 W. Bench‐scale single screw pressing was then performed. With the dry milled corn germ, no oil was obtained from the uncooked germ. A maximal yield of about 5% oil [26% of total oil recovery (TOR), relative to hexane extraction] was obtained by cooking the dry‐milled germ for 6.5 min in a conventional oven at 180°C before pressing. A maximal yield of about 7% oil (37% TOR) was obtained by cooking the dry‐milled germ for 4.5 min in a microwave oven at 1500 W before pressing. With the wet‐milled germ, yields of about 7% oil (18% TOR) were obtained with the uncooked germ and yields increased to a maximum of about 22% oil (56% TOR) by cooking in a conventional oven at 180°C for 5 min or a maximum of about 17% oil (44% TOR) by cooking for 4 min in a microwave oven at 1500 W. These results indicate that microwave and conventional oven cooking are both effective pretreatments before pressing. Microwave preheating resulted in higher oil yields with dry‐milled germ, and conventional oven pretreatment resulted in higher oil yields with factory‐dried wet‐milled corn germ.