bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cutoff value of lipid‐laden alveolar macrophages for diagnosing aspiration in infants and children
Authors: Furuya María E.Y. , Moreno‐Córdova Verónica , Ramírez‐Figueroa Jorge L. , Vargas Mario H. , Ramón‐García Guillermo , Juan David H. Ramírez‐San 
Published: April 2007

AbstractChronic passage of gastric and/or alimentary material into the airways is a frequent and difficult‐to‐diagnose condition. Because alveolar macrophages phagocytose aspirated material, it has been suggested that their identification is a useful diagnostic method. To know the usefulness of the lipid‐laden alveolar macrophages (LLAM) index as a diagnostic tool for aspiration, children from 1 month to 16 years of age were included in three groups: G‐I, children with pulmonary pathology and suspicion of aspiration by clinic or image evaluation; G‐II, with pulmonary pathology without suspicion of aspiration; and G‐III, without respiratory symptoms nor suspicion of aspiration. Bronchoalveolar lavage was obtained through bronchoscopy in G‐I and G‐II, and through endotracheal tube in G‐III, and the LLAM index (0–400) was determined. A total of 112 patients (41, 30, and 41 in G‐I to III, respectively) were studied. LLAM index (mean ± SEM) was highest in G‐I (233.2 ± 5.5), as compared with G‐II (187.8 ± 11.6, P < 0.05), and G‐III (108.5 ± 13.5, P < 0.001). However, notable overlap of LLAM values was observed between G‐I and G‐II, and between G‐II and G‐III. When patients from G‐I and G‐III were jointly analyzed, the area under the ROC curve for diagnosing aspiration was 0.92, with a best cutoff value of >165 (98.6% sensitivity, 78.0% specificity, 87.8% overall accuracy). LLAM index, with a cutoff value of >165 is a useful diagnostic test for aspiration when there is suspicion of this condition. However, due to its low specificity, it does not discriminate other causes of chronic lung disease. Pediatr Pulmonol. 2007; 42:452–457. © 2007 Wiley‐Liss, Inc.
Human metapneumovirus bronchiolitis in infancy is an important risk factor for asthma at age 5
Authors: García‐García M.L. , Calvo C. , Casas I. , Bracamonte T. , Rellán A. , Gozalo F. , Tenorio T. , Pérez‐Breña P. 
Published: April 2007

AbstractBackgroundHuman metapneumovirus (hMPV) infection plays an important role in the pediatric respiratory infections. However, little is known about the relationship between hMPV‐bronchiolitis and the development of subsequent wheezing. The aim of this study was to evaluate the outcome at third to fifth year after admission for hMPV‐bronchiolitis and to compare it with children admitted for respiratory syncytial virus (RSV)‐bronchiolitis and with children without lower respiratory disease in the first 2 years of life.MethodsWe studied 55 children (23 hMPV and 32 RSV acute bronchiolitis) aged 3–5 years and hospitalized during the seasons 2000–2005. Thirty‐eight children admitted due to acute rotavirus gastroenteritis in the same seasons, and without bronchiolitis during infancy, were also analyzed. Clinical data were collected through structured clinical interviews at the follow‐up visit. Skin prick tests to food and inhaled allergens were performed.ResultsAsthma was significantly more frequent in children with hMPV‐bronchiolitis (odds ratio (OR) = 5.21), RSV‐bronchiolitis (OR = 4.68), allergic rhinitis (OR = 1.7), and siblings with atopy (OR = 1.75). In the multivariate analyses, hMPV was the most important risk factor for asthma in preschool years (OR = 15.9), followed by RSV‐bronchiolitis (OR = 10.1) and allergic rhinitis (OR = 4.9).No differences were found with respect to allergic rhinitis, atopic dermatitis, food allergy, proportion of positive prick tests, family history of atopy, and asthma.ConclusionshMPV‐bronchiolitis in infancy was strongly associated with asthma as well as other forms of bronchial obstructive disease at third and fifth year of life. This association is, at least, as strong as the association observed with RSV infections. Pediatr Pulmonol. 2007; 42:458–464. © 2007 Wiley‐Liss, Inc.
Thermal Decomposition of Organic Peroxides TATP and HMTD by T‐Jump/FTIR Spectroscopy
Authors: Hiyoshi Reiko I. , Nakamura Jun , Brill Thomas B. 
Published: April 2007

AbstractThe thermal decomposition of the peroxides, triacetone triperoxide (TATP) and hexamethylene triperoxide diamine (HMTD) was investigated as a function of pressure, temperature and atmosphere by T‐jump/FT‐IR spectroscopy. In an Ar atmosphere at fast heating rates, the dominant decomposition product of TATP was methane rather than acetone which dominates at slow heating rates. The products of TATP were different in Ar and in air which implies that decomposition occurs primarily in the gas phase. In contrast, the products from HMTD were independent of the surrounding atmosphere implying that it decomposes primarily in the condensed phase. The IR spectra of the decomposition products of HMTD exhibited some dependence on pressure but not on the pyrolysis filament temperature.
Vapor Pressures, Mass Spectra and Thermal Decomposition Processes of Bis(2,2‐Dintropropyl)acetal (BDNPA) and Bis(2,2‐Dinitropropyl)formal (BDNPF)
Authors: Rauch Rory B. , Behrens Richard 
Published: April 2007

AbstractSimultaneous thermogravimetric modulated beam mass spectrometry (STMBMS) and Fourier‐transform ion cyclotron resonance (FTICR) instruments have been used to measure the mass spectra, measure vapor pressures and evaluate the thermal decomposition mechanism of bis(2,2‐dinitropropyl)acetal (BDNPA) and bis(2,2‐dinitropropyl)formal (BDNPF). The high mass accuracy FTICR mass spectra provide the chemical formulas of the ion fragments formed in the mass spectra of BDNPA, BDNPF and their decomposition products, and provide a basis for predicting possible structures of the ion fragments. The heat of vaporization (ΔvapH) and vapor pressure at 25 °C are 93.01±0.38 kJ/mol and 1.4532+0.40/−0.27 mPa for BDNPA, and 84.77±0.88 kJ/mol and 2.20+1.87/−1.07 mPa for BDNPF. STMBMS data support a nitro‐nitrite (NO2→ONO) rearrangement mechanism for both compounds. Upon rearrangement, both NO and NO2 are cleaved from the structure, thus producing a ketone radical. The nitro‐nitrite rearrangement begins to occur at appreciable rates between 160 and 180 °C. Additional decomposition products include amines, imines and amides, as well as CO2 and H2O at higher temperatures. STMBMS mass loss data suggest the formation of a residue during the decomposition of BDNPA and BDNPF. The major difference between the decomposition of the two compounds is the slower reaction rate of BDNPF. We postulate that the less sterically hindered formal carbon of BDNPF subjects it to interactions with an intermediate, thus forming a complex and delaying its release. Methods to elucidate complex thermal decomposition mechanisms from STMBMS data are illustrated.
Combustion Reactions of Poly(Carbon Monofluoride), (CF)n, with Different Reductants and Characterization of the Products
Authors: Cudziło Stanisław , Szala Mateusz , Huczko Andrzej , Bystrzejewski Michał 
Published: April 2007

AbstractMixtures of poly(carbon monofluoride) also known as graphite fluoride, (CF)n, with different reductants, such as NaN3, B, Ti, ZrTi, Si, CaSi2, AlSi, TiSi, MoSi2 and CrSi2 were investigated. Reactions between these substrates are fast and exothermic enough to proceed in a high temperature, self‐sustaining regime. Heat effects accompanying the reactions were measured and the solid reaction products were analyzed. SEM observation revealed the presence of exfoliated graphite in each case. Nanostructures, like nanofibers, nanorods, nanospheres and nanosized crystals, were also present in most of the products. Phase (XRD) and elemental composition as well as porous structure (N2 adsorption) of chosen reaction products were also determined.
Application of Cerimetric Methods for Determining the Metallic Aluminum Content in Ultrafine Aluminum Powders
Authors: Fedotova Tatyana D. , Glotov Oleg G. , Zarko Vladimir E. 
Published: April 2007

AbstractUltrafine (nano‐sized) aluminum is a promising component for solid propellants, gel propellants, explosives, etc. The work is focused upon a problem of determining active (metallic) aluminum content in nanoAl powders as one of the characteristics of their reactivity. It is shown that the high reactivity, the presence of either the gases adsorbed or coating matter on the particle surface restricts the traditionally used permanganatometric and volumetric analytic methods. A new technique determining the active aluminum content is presented. This is the adaptation of known cerimetric method based on the analytical reaction Ce4++e−=Ce3+. The method can be applied for analysis of metallic aluminum in the probes of nanoAl (including ones with organic coating), as well as micron sized aluminum, and their condensed combustion products.
On Shear Rheology of Gel Propellants
Authors: Rahimi Shai , Peretz Arie , Natan Benveniste 
Published: April 2007

AbstractSelected fuel, oxidizer and simulant gels were prepared and rheologically characterized using a rotational rheometer. For fuel gelation both organic and inorganic gellants were utilized, whereas oxidizers and simulants were gelled with addition of silica and polysaccharides, respectively. The generalized Herschel‐Bulkley constitutive model was found to most adequately represent the gels studied. Hydrazine‐based fuels, gelled with polysaccharides, were characterized as shear‐thinning pseudoplastic fluids with low shear yield stress, whereas inhibited red‐fuming nitric acid (IRFNA) and hydrogen peroxide oxidizers, gelled with silica, were characterized as yield thixotropic fluids with significant shear yield stress. Creep tests were conducted on two rheological types of gels with different gellant content and the results were fitted by Burgers‐Kelvin viscoelastic constitutive model. The effect of temperature on the rheological properties of gel propellant simulants was also investigated. A general rheological classification of gel propellants and simulants is proposed.
An Advanced GAP/AN/TAGN Propellant. Part I: Ballistic Properties
Authors: Judge Michael D. , Lessard Pierre 
Published: April 2007

AbstractA solid rocket propellant based on glycidyl azide polymer (GAP) binder plasticized with nitrate esters and oxidized with a mixture of ammonium nitrate (AN) and triaminoguanidine nitrate (TAGN) was formulated and characterized. Non‐lead ballistic modifiers were also included in order to obtain a propellant with non‐acidic and non‐toxic exhaust. This propellant was found to exhibit a burning rate approximately twice that of standard GAP/AN propellants. The exponent of the propellant is high compared to commonly used composite propellants but is still in the useable range at pressures below 13.8 MPa. This propellant may present a good compromise for applications requiring intermediate burn rate and impulse combined with low‐smoke and non‐toxic exhaust.
Targeted molecular dynamics simulation studies of binding and conformational changes in E. coli MurD
Authors: Perdih Andrej , Kotnik Miha , Hodoscek Milan , Solmajer Tom 
Published: April 2007

AbstractEnzymes involved in the biosynthesis of bacterial peptidoglycan, an essential cell wall polymer unique to prokaryotic cells, represent a highly interesting target for antibacterial drug design. Structural studies of E. coli MurD, a three‐domain ATP hydrolysis driven muramyl ligase revealed two inactive open conformations of the enzyme with a distinct C‐terminal domain position. It was hypothesized that the rigid body rotation of this domain brings the enzyme to its closed active conformation, a structure, which was also determined experimentally. Targeted molecular dynamics 1 ns‐length simulations were performed in order to examine the substrate binding process and gain insight into structural changes in the enzyme that occur during the conformational transitions into the active conformation. The key interactions essential for the conformational transitions and substrate binding were identified. The results of such studies provide an important step toward more powerful exploitation of experimental protein structures in structure‐based inhibitor design. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Structural and kinetic analysis of proton shuttle residues in the active site of human carbonic anhydrase III
Authors: Elder Ileana , Fisher Zoë , Laipis Philip J. , Tu Chingkuang , McKenna Robert , Silverman David N. 
Published: April 2007

AbstractWe report the X‐ray crystal structures and rate constants for proton transfer in site‐specific mutants of human carbonic anhydrase III (HCA III) that place a histidine residue in the active‐site cavity: K64H, R67H, and K64H‐R67N HCA III. Prior evidence from the exchange of 18O between CO2 and water measured by mass spectrometry shows each mutant to have enhanced proton transfer in catalysis compared with wild‐type HCA III. However, His64 in K64H and K64H‐R67N HCA III have at most a capacity for proton transfer that is only 13% that of His64 in HCA II. This reduced rate in mutants of HCA III is associated with a constrained side‐chain conformation of His64, which is oriented outward, away from the active‐site zinc in the crystal structures. This conformation appears stabilized by a prominent π stacking interaction of the imidazole ring of His64 with the indole ring of Trp5 in mutants of HCA III. This single orientation of His64 in K64H HCA III predominates also in a double mutant K64H‐R67N HCA III, indicating that the positive charge of Arg67 does not influence the observed conformation of His64 in the crystal structure. Hence, the structures and catalytic activity of these mutants of HCA III containing His64 account only in small part for the lower activity of this isozyme compared with HCA II. His67 in R67H HCA III was also shown to be a proton shuttle residue, having a capacity for proton transfer that was approximately four times that of His64 in K64H HCA III. This is most likely due to its proximity and orientation inward towards the zinc‐bound solvent. These results emphasize the significance of side chain orientation and range of available conformational states as characteristics of an efficient proton shuttle in carbonic anhydrase. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Structural prediction of the β‐domain of metallothionein‐3 by molecular dynamics simulation
Authors: Ni Feng‐Yun , Cai Bin , Ding Zhi‐Chun , Zheng Fei , Zhang Ming‐Jie , Wu Hou‐Ming , Sun Hong‐Zhe , Huang Zhong‐Xian 
Published: April 2007

AbstractThe β‐domain of metallothionein‐3 (MT3) has been reported to be crucial to the neuron growth inhibitory bioactivity. Little detailed three‐dimensional structural information is available to present a reliable basis for elucidation on structure–property–function relationships of this unique protein by experimental techniques. So, molecular dynamics simulation is adopted to study the structure of β‐domain of MT3. In this article, a 3D structural model of β‐domain of MT3 was generated. The molecular simulations provide detailed protein structural information of MT3. As compared with MT2, we found a characteristic conformation formed in the fragment (residue 1–13) at the N‐terminus of MT3 owing to the constraint induced by 5TCPCP9, in which Pro7 and Pro9 residues are on the same side of the protein, both facing outward and the two 5‐member rings of prolines are arranged almost in parallel, while Thr5 is on the opposite side. Thr5 in MT3 is also found to make the first four residues relatively far from the fragment (residue 23–26) as compared with MT2. The simulated structure of β‐domain of MT3 is looser than that of MT2. The higher energy of MT3 than that of MT2 calculated supports these conclusions. Simulation on the four isomer arising from the cis‐ or trans‐configuration of 6CPCP9 show that the trans‐/trans‐isomer is energetic favorable. The partially unfolding structure of β‐domain of MT3 is also simulated and the results show the influence of 6CPCP9 sequence on the correct folding of this domain. The correlations between the bioactivity of MT3 and the simulated structure as well as the folding of β‐domain of MT3 are discussed based on our simulation and previous results. Proteins 2007. © 2007 Wiley‐Liss, Inc.
GISAXS study of carbon nanotubes grown by CVD
Authors: Mane Mane J. , Cojocaru C. S. , Barbier A. , Deville J.‐P. , Jean B. , Metzger T. H. , Thiodjio Sendja B. , Le Normand F. 
Published: April 2007

AbstractWe report a quantitative Grazing Incidence Small Angle X‐ray Scattering (GISAXS) study of a dense film of mutually oriented carbon nanotubes (CNTs) grown by a catalytically‐activated DC HF CCVD process after dispersion of metallic catalytic (Co) islands on SiO2/Si(100) substrates. The GISAXS pattern analysis is expanded to non‐correlated surface science systems and is based on CNTs density, characteristic lengths, atomic Co dispersion throughout the CNTs and roughnesses of uncorrelated particles. The results are closely compared to SEM and TEM observations. The GISAXS patterns, even dominated by envelope features of disordered objects, provide significant complementary quantitative data about CNTs films. The results underline that cobalt continuously fills the nanotube in the course of the growth and that the CNTs experience a large tendency toward mutual alignment. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Robot‐assisted minimally invasive lung brachytherapy
Authors: Trejos A. L. , Lin A. W. , Pytel M. P. , Patel R. V. , Malthaner R. A. 
Published: April 2007

AbstractBackgroundThis paper presents a novel alternative for the treatment of lung cancer. The method consists of accessing the lung through small incisions in a minimally invasive manner in order to insert radioactive seeds directly into the lung using a robotic surgical system.MethodsAn experimental test‐bed to evaluate the feasibility of this approach has been developed. It consists of two surgical robotic systems, a device specifically designed to robotically implant radioactive seeds, needle tracking software, ultrasound imaging, electromagnetic tracking, and a surgical box that mimics a patient's thorax. A detailed comparison has been performed between currently available access options and robot‐assisted minimally invasive access.ResultsThe results show insignificant differences in accuracy between the methods, with the exception of a significant improvement when electromagnetic (EM) guidance was added to the non‐robotic techniques. The navigation system reduced the number of attempts for all seed delivery methods. Significant reductions in time were achieved in the minimally invasive procedures by the addition of EM guidance.ConclusionsThe performance achieved when using robotic systems and image guidance for minimally‐invasive brachytherapy is clinically comparable to that acieved in an open surgery procedure, while reducing the invasiveness of the procedure, improving ergonomic conditions for the clinician and reducing radiation exposure. Copyright © 2007 John Wiley & Sons, Ltd.
The accuracy of computer‐assisted surgical planning in soft tissue prediction following orthognathic surgery
Authors: Pektas Z. Ö. , Kircelli B. H. , Cilasun Ü. , Uckan S. 
Published: April 2007

AbstractBackgroundThe purpose of the present study was to evaluate the accuracy of a computer‐assisted imaging system in predicting the soft tissue response following orthognathic surgery.MethodsThe study sample consisted of 11 adult patients with a mean age of 23.5 years. The preoperative and postoperative lateral cephalograms were obtained after orthodontic preparation and immediately before surgery and at least 1 year after surgery. The computer‐generated soft tissue image and the actual surgical outcome were compared to evaluate the accuracy of the imaging system.ResultsIn the sagittal plane, the tip of nose was the most accurate site and the largest difference was shown in the upper lip. The lower lip was noted to be the least accurate and the subnasale the most accurate region in the vertical plane. Predictions were found to be more accurate for the sagittal plane when compared with those for the vertical plane.ConclusionsComputer‐assisted visual treatment objectives was proved to be satisfactory in predicting the soft tissue outcome following orthognathic surgery. Copyright © 2007 John Wiley & Sons, Ltd.
Experiences with an application of industrial robotics for accurate patient positioning in proton radiotherapy
Authors: Allgower C. E. , Schreuder A. N. , Farr J. B. , Mascia A. E. 
Published: April 2007

AbstractBackgroundProtons beams deliver targeted radiation doses with greater precision than is possible with electrons or megavoltage X‐ray photons, but to retain this advantage, patient positioning systems at proton clinics must meet tighter accuracy requirements. For this and other reasons, robots were incorporated into the treatment room systems at MPRI.MethodsThe Midwest Proton Radiotherapy Institute (MPRI) is the first radiotherapy facility in the United States to use commercial robots with six degrees of freedom for patient positioning, rather than a traditional bed with four degrees of freedom.ResultsThis paper outlines the ways in which robots are used at MPRI and attempts to distil insights from the experience of treating over 200 radiotherapy patients with a robotic system from February 2004 to late 2006.ConclusionsThe system has performed well, and with great reliability, but there is room for future improvement, especially in ease of use and in reducing the time to get patients into position. Copyright © 2007 John Wiley & Sons, Ltd.
ToF‐SIMS depth profiling of a complex polymeric coating employing a C60 sputter source
Authors: Hinder Steven J. , Lowe Chris , Watts John F. 
Published: April 2007

AbstractA complex poly(vinylidene difluoride) (PVdF)/poly(methyl methacrylate) (PMMA)‐based coil coating formulation has been investigated using time‐of‐flight SIMS (ToF‐SIMS). Employing a Bi3+ analysis source and a Buckminsterfullerene (C60) sputter source, depth profiles were obtained through the polymeric materials in the outer few nanometres of the PVdF topcoat. These investigations demonstrate that the PVdF coating's air/coating interface is composed principally of the flow agent included in the formulation. Elemental depth profiles obtained in the negative ion mode demonstrate variations in the carbon, oxygen and fluorine concentrations within the coating with respect to depth. All three elemental depth profiles suggest that the PVdF coating bulk possesses a constant material composition. The oxygen depth profile reveals the presence of a very thin oxygen‐rich sub‐surface layer in the PVdF coating, observed within the first second of the sputter/etch profile. Retrospectively, extracted mass spectra (from the elemental depth profile raw data set) of the PVdF coating sub‐surface and bulk layers indicates this oxygen‐rich sub‐surface layer results from segregation of the acrylic co‐polymers in the formulation towards the PVdF coating air/coating interface. Molecular depth profiles obtained in both the positive and negative secondary ion modes provide supporting evidence to that of the elemental depth profiles. The molecular depth profiles confirm the presence of a sub‐surface layer rich in the acrylic co‐polymers indicating segregation of the co‐polymers towards the PVdF topcoats air‐coating surface. The molecular depth profiles also confirm that the PVdF component of the topcoat is distributed throughout the coating but is present at a lower concentration at the air‐coating interface and in the sub‐surface regions of the coating, than in the coating bulk. Copyright © 2007 John Wiley & Sons, Ltd.