bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Use of Inverse Gas Chromatography (IGC) to Determine the Surface Energy of RDX
Authors: Luo Yunjun , Du Meina 
Published: December 2007

AbstractThe surface properties of RDX play an important role in enhancing mechanics performances of the propellants and explosives. In this work, thereby, inverse gas chromatography (IGC) using various probe liquids as the medium was used to determine the surface energy components of RDX containing both dispersive and polar components, which were acquired respectively from neutral probe liquids (such as n‐hexane, n‐heptane, n‐octane) and polar probe liquids (such as chloroform, benzene, methanol). The results show that RDX located in different column temperatures has difference in the surface energy and possesses more surface energy when there is high temperature. The calculated formula of the total surface energy with temperature is: $\rm{ {\rm{\gamma }}_{\rm{s}}^{\rm{T}} {\rm{ = }} - {\rm{82}}{\rm{.16}} + }$ $\rm{{\rm{0}}{\rm{.3557}}T}$, and it is also found that dispersive, polar, electron acceptor, and electron donor components of RDX are $\rm{{\rm{\gamma }}_{\rm{s}}^{{\rm{LW}}} {\rm{ = }} - {\rm{53}}{\rm{.29}} + {\rm{0}}{\rm{.2560}}T}$, $\rm{ {\rm{\gamma }}_{\rm{s}}^{{\rm{AB}}} {\rm{ = }} - {\rm{28}}{\rm{.57}} + {\rm{0}}{\rm{.09889}}T}$, $\rm{ {\rm{\gamma }}_{\rm{s}}^{\rm{ + }} {\rm{ = }} - {\rm{25}}{\rm{.82}} }$ $\rm{+ {\rm{0}}{\rm{.08943}}T}$, and $\rm{ {\rm{\gamma }}_{\rm{s}}^ - {\rm{ = }} }$ $\rm{- {\rm{7}}{\rm{.932}} + {\rm{0}}{\rm{.02743}}T}$, respectively. These results demonstrate that the dispersive component is the primary part of the total surface energy, and RDX has an acid performance.
Shear Initiation of Al/MoO3‐Based Reactive Materials
Authors: Bouma Richard H. B. , Meuken Denise , Verbeek Ries , Martinez Pacheco Maria , Katgerman Laurens 
Published: December 2007

AbstractReactive mixtures based on nano aluminium and nano‐ or micron size molybdenum trioxide have been pressed. These energetic mixtures have been tested in the Ballistic Impact Chamber and as an energetic projectile impacting a steel plate. Al/MoO3‐based reactive mixtures can be initiated by a controlled mechanical stimulus. The sensitivity depends on deformation velocity, pressing density, addition of fluorine containing binder and particle size. Nanometric mixtures of Al and MoO3 have a shorter time to reaction compared to the corresponding mixtures with micron size MoO3. The sensitivity decreases with increase in porosity. No influence of fuel/oxidizer ratio has been found in the experiments. An extensive deformation is needed before the start of reaction is observed. An analytical evaluation of shear rate cannot be applied as a detailed numerical simulation of the deformation process in PBXN‐109 shows.
An Investigation on Thermal Decomposition of DNTF‐CMDB Propellants
Authors: Zheng Wei , Wang Jiangning , Ren Xiaoning , Zhang Laying , Zhou Yanshui 
Published: December 2007

AbstractThe thermal decomposition of DNTF‐CMDB propellants was investigated by pressure differential scanning calorimetry (PDSC) and thermogravimetry (TG). The results show that there is only one decomposition peak on DSC curves, because the decomposition peak of DNTF cannot be separated from that of the NC/NG binder. The decomposition of DNTF can be obviously accelerated by the decomposition products of the NC/NG binder. The kinetic parameters of thermal decompositions for four DNTF‐CMDB propellants at 6 MPa were obtained by the Kissinger method. It is found that the reaction rate decreases with increasing content of DNTF.
γ‐FOX‐7: Structure of a High Energy Density Material Immediately Prior to Decomposition
Authors: Crawford Margaret‐Jane , Evers Jürgen , Göbel Michael , Klapötke Thomas M. , Mayer Peter , Oehlinger Gilbert , Welch Jan M. 
Published: December 2007

Abstract1,1‐Diamino‐2,2‐dinitroethene, C2H4N4O4 (FOX‐7), is a novel high energy density material with low friction and impact sensitivity and a high activation barrier to detonation. In this study, the previously unknown crystal structure of the γ‐polymorph of trimorphic FOX‐7 is reported. γ‐FOX‐7 is stable from ∼435 K until the compound decomposes just above 504 K. A single crystal of α‐FOX‐7 (P21/n, Z=4, a=694.67(7) pm, b=668.87(9) pm, c=1135.1(1) pm, β=90.14(1)°, T=373 K) was first transformed into a single crystal of β‐FOX‐7 (P212121, Z=4, a=698.6(1) pm, b=668.6(2) pm, c=1168.7(3) pm, T=423 K) and then into a single crystal of γ‐FOX‐7 at 450 K. The γ‐FOX‐7 crystal was then subsequently quenched to 200 K. The structure of γ‐FOX‐7 (P21/n, Z=8, a=1335.4(3) pm, b=689.5(1) pm, c=1205.0(2) pm, β=111.102(8)°, T=200 K) consists of four planar layers, each containing two crystallographically independent FOX‐7 molecules found in the asymmetric unit.
Development of Nanothermite Composites with Variable Electrostatic Discharge Ignition Thresholds
Authors: Foley Timothy , Pacheco Adam , Malchi Jonathan , Yetter Richard , Higa Kelvin 
Published: December 2007

AbstractA brief description of an apparatus for testing the electrostatic discharge ignition threshold for sensitive materials is presented. This apparatus was used to demonstrate how fluorocarbons could alter the propensity of a nanothermite to ignite. In addition to these findings, the effect of the fluorocarbon on the pressure output of the material is reported.
Tilted peptides: a structural motif involved in protein membrane insertion?
Authors: Lins L. , Brasseur R. 
Published: December 2007

AbstractTilted peptides are short hydrophobic protein fragments characterized by an asymmetric distribution of their hydrophobic residues when helical. They are able to interact with a hydrophobic/hydrophilic interface (such as a lipid membrane) and to destabilize the organized system into which they insert. They were detected in viral fusion proteins and in proteins involved in different biological processes involving membrane insertion or translocation of the protein in which they are found. In this paper, we have analysed different protein domains related to membrane insertion with regard to their tilted properties. They are the N‐terminal signal peptide of the filamentous haemagglutinin (FHA), a Bordetella pertussis protein secreted in high amount and the hydrophobic domain from proteins forming pores (i.e. ColIa, Bax and Bcl‐2). From the predictions and the experimental approaches, we suggest that tilted peptides found in those proteins could have a more general role in the mechanism of insertion/translocation of proteins into/across membranes. For the signal sequences, they could help the protein machinery involved in protein secretion to be more active. In the case of toroidal pore formation, they could disturb the lipids, facilitating the insertion of the other more hydrophilic helices. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
T‐20 and T‐1249 HIV fusion inhibitors' structure and conformation in solution: a molecular dynamics study
Authors: Martins Do Canto António M. T. , Palace Carvalho A. J. , Prates Ramalho J. P. , Loura Luís M. S. 
Published: December 2007

AbstractFusion of the HIV envelope with the target cell membrane is a critical step of the HIV entry into the target cell. Several peptides based on the C‐region of HIV gp41 have been used in clinical trials as possible HIV fusion inhibitors. Among these are T‐1249 and T‐20 (also known as enfurvitide). Despite recent works, a detailed molecular picture of the inhibitory mechanism of these molecules is still lacking. These peptides are usually depicted as α‐helices by analogy with the structure of the sequence of the gp41 protein with which they are homologous. However, structures like these would be highly unstable in solution and thus would not explain, by themselves, the ability that the two fusion inhibitors have to become solvated by water and also interact effectively with cell membranes. To this effect, extensive molecular dynamics simulations were carried out to investigate the structure and conformational behavior of T‐1249 and T‐20 in water, as well as shorter homologous peptides CTP and 3f5, which show no inhibitory action. We found that the studied inhibitors have no stable structure in solution in the time scale studied. Additionally, the solvent accessible area varies significantly during the simulation. Our findings suggest that these peptides may assume not only one, but several possible sets of structures in solution, some of which more adequate to interact with the solvent, whereas others might be better suited to interact with cell membranes. Interestingly, and in accordance with published experimental studies, we verified that T‐1249 displays considerably larger α‐helical structure than T‐20. Taking into account a recent study with design peptides with increased helicity, it is possible that this feature may be related to the increased inhibiting efficiency of T‐1249 relative to that of T‐20. Copyright © 2007 European Peptide Society and John Wiley & Sons, Ltd.
Coupling desorption electrospray ionisation and neutral desorption/extractive electrospray ionisation with a travelling‐wave based ion mobility mass spectrometer for the analysis of drugs
Authors: Williams Jonathan P. , Scrivens James H. 
Published: December 2007

AbstractDesorption electrospray ionisation (DESI) and neutral desorption/extractive electrospray ionisation (EESI) have been coupled to a hybrid quadrupole travelling‐wave (T‐Wave)‐based ion mobility time‐of‐flight mass spectrometer for the direct accurate mass analysis of active ingredients formulated into pharmaceutical samples. The collision cross‐section measurements of polyethylene glycol (PEG) excipients detected in one formulation were estimated and compared with published data. These estimated collision cross‐sections of the PEG species showed good agreement with published data. Copyright © 2007 John Wiley & Sons, Ltd.
Combining data from multiple sources, with applications to environmental risk assessment
Authors: Ryan Louise 
Published: December 2007

AbstractThe classical statistical paradigm emphasizes the development and application of methods to account for sampling variability. Many modern day applications, however, require consideration of other sources of uncertainty that are not so easy to quantify. This paper presents a case study involving an assessment of the impact of in‐utero methylmercury exposure on the Intelligence Quotient (IQ) of young children. We illustrate how familiar techniques such as hierarchical modeling, Bayesian methods and sensitivity analysis can be used to aid decision making in settings that involve substantial uncertainty. Copyright © 2007 John Wiley & Sons, Ltd.
Latent transition analysis: Inference and estimation
Authors: Chung Hwan , Lanza Stephanie T. , Loken Eric 
Published: December 2007

AbstractParameters for latent transition analysis (LTA) are easily estimated by maximum likelihood (ML) or Bayesian methodviaMarkov chain Monte Carlo (MCMC). However, unusual features in the likelihood can cause difficulties in ML and Bayesian inference and estimation, especially with small samples. In this study we explore several problems in drawing inference for LTA in the context of a simulation study and a substance use example. We argue that when conventional ML and Bayesian estimates behave erratically, problems often may be alleviated with a small amount of prior input for LTA with small samples. This paper proposes a dynamic data‐dependent prior for LTA with small samples and compares the performance of the estimation methods with the proposed prior in drawing inference. Copyright © 2007 John Wiley & Sons, Ltd.
Bayesian sample size for exploratory clinical trials incorporating historical data
Authors: Whitehead John , Valdés‐Márquez Elsa , Johnson Patrick , Graham Gordon 
Published: December 2007

AbstractThis paper presents a simple Bayesian approach to sample size determination in clinical trials. It is required that the trial should be large enough to ensure that the data collected will provide convincing evidence either that an experimental treatment is better than a control or that it fails to improve upon control by some clinically relevant difference. The method resembles standard frequentist formulations of the problem, and indeed in certain circumstances involving ‘non‐informative’ prior information it leads to identical answers. In particular, unlike many Bayesian approaches to sample size determination, use is made of an alternative hypothesis that an experimental treatment is better than a control treatment by some specified magnitude. The approach is introduced in the context of testing whether a single stream of binary observations are consistent with a given success rate p0. Next the case of comparing two independent streams of normally distributed responses is considered, first under the assumption that their common variance is known and then for unknown variance. Finally, the more general situation in which a large sample is to be collected and analysed according to the asymptotic properties of the score statistic is explored. Copyright © 2007 John Wiley & Sons, Ltd.
The impact of a misspecified random‐effects distribution on the estimation and the performance of inferential procedures in generalized linear mixed models
Authors: Litière S. , Alonso A. , Molenberghs G. 
Published: December 2007

AbstractEstimation in generalized linear mixed models (GLMMs) is often based on maximum likelihood theory, assuming that the underlying probability model is correctly specified. However, the validity of this assumption is sometimes difficult to verify. In this paper we study, through simulations, the impact of misspecifying the random‐effects distribution on the estimation and hypothesis testing in GLMMs. It is shown that the maximum likelihood estimators are inconsistent in the presence of misspecification. The bias induced in the mean‐structure parameters is generally small, as far as the variability of the underlying random‐effects distribution is small as well. However, the estimates of this variability are always severely biased. Given that the variance components are the only tool to study the variability of the true distribution, it is difficult to assess whether problems in the estimation of the mean structure occur. The type I error rate and the power of the commonly used inferential procedures are also severely affected. The situation is aggravated if more than one random effect is included in the model. Further, we propose to deal with possible misspecification by way of sensitivity analysis, considering several random‐effects distributions. All the results are illustrated using data from a clinical trial in schizophrenia. Copyright © 2007 John Wiley & Sons, Ltd.
Flavins as organocatalysts for environmentally benign molecular transformations
Authors: Imada Yasushi , Naota Takeshi 
Published: December 2007

AbstractRecent progress in the development of flavin‐catalyzed oxidations and related reactions is described with respect to scope, limitation, and reaction mechanism. The 4a‐hydroperoxyflavins, which are the most simplified model compounds of flavoenzymes, act as catalytically active species for the oxidation of organic substrates with the help of H2O2 or O2 as a mild oxidant. This principle behind the simulation of flavoenzymes led to the discovery of a variety of environmentally benign, oxidative transformations of secondary amines to nitrones, tertiary amines to N‐oxides, sulfides to sulfoxides, and Baeyer–Villiger oxidations of ketones. Asymmetric oxidation of sulfides can also be performed with several chiral flavin catalysts. One of the fortunate outcomes of this study is the development of an environmentally friendly (“green”) method for the “aerobic hydrogenation” of olefins, which is achieved by in situ generation of diimide with the aid of the flavin‐catalyzed oxidation of hydrazine under an O2 atmosphere. © 2007 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 7: 354–361; 2007: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.20135
Human fetal cardiovascular profile score and neonatal outcome in intrauterine growth restriction
Authors: Mäkikallio K. , Räsänen J. , Mäkikallio T. , Vuolteenaho O. , Huhta J. C. 
Published: December 2007

AbstractObjectiveTo determine whether low cardiovascular profile (CVP) score has prognostic value for predicting neonatal mortality and severe morbidity in human fetuses with growth restriction.MethodsSeventy‐five consecutive growth‐restricted fetuses with Doppler examination of cardiovascular hemodynamics within a week prior to delivery comprised the study population. Hydrops, heart size, cardiac function and venous and arterial hemodynamics were evaluated for CVP score. The primary outcome measures were neonatal mortality and cerebral palsy.ResultsDuring the neonatal period, six of 75 neonates died and two had cerebral palsy (Group 1, n = 8). Compared with the fetuses discharged home from hospital (Group 2, n = 67), those in Group 1 were delivered at an earlier gestational age (28 (range, 24–35) weeks vs. 35 (range, 26–40) weeks, P < 0.01) and had lower CVP scores (4 (range, 2–6) vs. 9 (range, 5–10), P < 0.0001). All CVP subscale scores were lower (P < 0.01) in Group 1 than in Group 2 fetuses. Gestational age‐adjusted hazard ratios (95% CIs) for adverse neonatal outcome were highest for cardiomegaly (13.9 (1.7–114.3), P = 0.014), monophasic atrioventricular filling pattern or holosystolic tricuspid regurgitation (9.5 (2.3–38.4), P = 0.002) and atrial pulsations in the umbilical vein 7.7 (1.4–41.2), P = 0.017).ConclusionsGrowth‐restricted fetuses with adverse neonatal outcome have lower CVP scores than do fetuses with favorable neonatal outcome. The strongest predictors for adverse neonatal outcome in the CVP score were cardiomegaly, abnormal cardiac function with monophasic atrioventricular filling or holosystolic tricuspid regurgitation and increased systemic venous pressure. These assessments have independent prognostic power for adverse neonatal outcome even after adjustment for gestational age. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
The Potential Role for Xanthine Oxidase Inhibition in Major Intra‐abdominal Surgery
Authors: Mittal Anubhav , Phillips Anthony R. J. , Loveday Benjamin , Windsor John A. 
Published: December 2007

AbstractBackgroundXanthine oxidase (XO) is a cytosolic metalloflavoprotein that has been implicated in the pathogenesis of a wide spectrum of diseases, and is thought to be the most important source of oxygen‐free radicals and cell damage during re‐oxygenation of hypoxic tissues. Clinical studies
have already shown that XO inhibition is safe and effective for the treatment of gout, tumour‐lysis syndrome, and to reduce complications such as post‐operative arrhythmias, myocardial infarction and mortality in cardiovascular surgery. Here, we review the evidence from two decades of animal studies that have investigated the effects of XO inhibition during intra‐abdominal surgery.
Materials and methodsA search of the Ovid MEDLINE database from 1950 through January 2007 was carried out using the following search terms: xanthine oxidase, allopurinol, ischemia, reperfusion, intestine, bowel, and general surgery.ResultsThe inhibition of XO has been shown to reduce oxidative stress, neutrophil priming, damage to intestinal mucosa due to ischemia reperfusion injuries, intestinal anastomotic dehiscence, bacterial translocation, adhesion formation, distant organ injury and mortality.ConclusionsDespite this evidence which very strongly suggests a likely clinically beneficial role for XO inhibition in the elective and acute operative setting, it is surprising that such an approach has not been investigated in general surgery. There is now sufficient evidence to justify dedicated studies to determine the clinical benefits, dosing and duration of XO inhibition before and after gastrointestinal surgery.
Partitioning of Fatty Acids in Oil/Water Systems Analyzed by HPLC
Authors: Bravo Bélgica , Sánchez Jhoana , Cáceres Ana , Chávez Gerson , Ysambertt Fredy , Márquez Nelson , Jaimes Maria , Briceño Maria Isabel , Salager Jean Louis 
Published: December 2007

AbstractSurfactant/oil/water systems in which the surface‐active substance is a mixture of an undissociated fatty acid (FA) and its sodium salt soap, exhibit the typical phase behavior and the general emulsion phenomenology produced by a formulation scan. The phase behavior transition is induced by changing the FA concentration in the system at a fixed alkaline (NaOH) content in water, which results in a variable lipophilic acid/hydrophilic salt ratio. The partitioning is reported for different FA types (octanoic to myristic) and alcohol co‐surfactants between excess oil and water phases of Winsor three‐phase optimum formulation system. The concentrations are determined by using a method reported in a previous work to quantify the total acid fraction in each phase.
Interactions of Sodium Dodecyl Benzene Sulfonate and Sodium Dodecyl Sulfate with Gelatin: A Comparison
Authors: George Jinu , Nair S. M. , Sreejith Lisa 
Published: December 2007

AbstractThe interaction of SDS/SDBS in aqueous gelatin solutions is studied above the gelation temperature by viscosity and circular dichroism (CD) measurements. The steep rise observed in the relative viscosity can be due the structural transitions leading to micellar growth of higher order. Circular dichroism spectra indicated that gelatin helped in inducing the sphere→rod transition, without suffering any conformational changes within it. The findings are particularly significant in terms of the head group contribution, hydrophobic interaction and the formation of formulated complexes.
Evidence for the deliberate distortion of the Spanish Philippine colonial historical record in The Philippine Islands 1493–1898
Authors: Cano Glòria 
Published: December 2007

AbstractThe Philippine Islands 1493–1898 was a compilation of documents translated from the Spanish and edited by Emma H. Blair and James A. Robertson. The former was the brains behind the project. The editors received assistance from a reviewer, one James A. LeRoy, who introduced himself as an expert in Philippine matters. The personal correspondence amongst the three persons showed how The Philippine Islands 1493–1898 was constructed. Blair fully trusted LeRoy's knowledge and consulted him with doubts about translation. In turn, LeRoy advised Robertson to select documents for publication and warned him about unreliable Spanish, Filipino and English scholars. The correspondence helps to explain how The Philippine Islands 1493–1898 developed into a political tool in the service of the United States in order to explain the problems the Americans confronted in their new colony – a Spanish inheritance and the difficulties of training uneducated Filipinos for self-government.
Sutomo, the Indonesian Study Club and organised labour in late colonial Surabaya
Authors: Ingleson John 
Published: December 2007

AbstractThe labour movement in colonial Indonesia is an important part of Indonesian history. The accepted convention is that after 1926, there was little or no labour activity in the colony, or at least little of any consequence. This article argues that much was going on but that it was of a different character from earlier years because of the limitations imposed by the colonial government. The Indonesian Study Club, based in Surabaya and led by Dr Sutomo, had a central role. The creation of labour unions was part of a broader effort to create enduring linkages between the western educated Surabaya elite and Surabaya workers.