bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biological Plate Osteosynthesis of Comminuted Subtrochanteric Fractures: A Clinical Study
Authors: Mehrpour Saeed Reza , Aghamirsalim Mohamadreza , Tavvafi Mohamadreza , Sorbi Reza 
Published: June 2012

Background Comminuted subtrochantric fractures represent a challenge for trauma surgeons. Achieving appropriate reduction and stable fixation can be difficult, some techniques being associated with technical difficulties and complications. The aim of this study is the assessment of biologic fixation in comminuted subtrochantric fractures. Method Twenty six men with comminuted subtrochanteric femoral fractures treated by bridging dynamic hip screw were prospectively studied. Patients were assessed clinically for pain, hip and knee range of motion, angular and rotational deformities and leg-length discrepancy. Union was assessed radiographically. Results Seinheimer classification: 8 fractures were type III, 11 patients type IV and seven patients type V. Fixation was performed with dynamic hip screw (DHS). Union occurred in all cases. None of the patients had clinical pain or dysfunction. Discussion We highly recommend submuscular plating in the treatment of comminuted subtrochantric fractures especially in the third world.
Managing Obsolescence in the Aircraft Life cycle
Authors: Jones Derek , Seabridge Allan 
Published: June 2012

Abstract
In a complex aerospace product with long development time scales and long durations of in‐service use there are many opportunities for obsolescence to appear. Apart from the obvious examples of obsolete technology and component parts, obsolescence is often a major factor in the initial operational requirement or indeed, the design and manufacturing processes, the design toolset, organizational skills, support, and operations as well as the information processing system that supports this.
A failure to recognize where obsolescence can exert an influence can lead to major costs in the project life cycle as a result of a failure to meet the original specification or a failure to respond to competition in the market place.
The authors believe that a comprehensive knowledge of where obsolescence can strike and how to plan to manage obsolescence must be incorporated into the earliest stages of design.
Structural Design – Tradeoffs
Authors: Kassapoglou Christos , van Tooren Michel 
Published: June 2012

AbstractAn overview of the design process for airframe structures is presented. It summarizes the tradeoffs between structural requirements and manufacturing considerations. The design process examines all possible failure modes and attempts to sequence them in a way that weight is minimized and the failure sequence is beneficial for the overall structure when failure occurs (e.g., for improved damage tolerance). At the same time manufacturing constraints and high cost manufacturing steps are traded in order to minimize cost. In the end, the overall tradeoff between weight and cost leads to the best design given specific preferences and priorities that the designer may have on the relative importance of cost and weight. The design of a stiffened panel is used as an example to highlight the design process and tradeoffs.
Human 5‐Lipoxygenase
Authors: Newcomer Marcia E , Gilbert Nathaniel C , Funk Max O 
Published: June 2012

AbstractThe enzyme 5‐lipoxygenase initiates the biosynthesis of leukotrienes, lipid mediators of the inflammatory response. The enzyme is also required for the synthesis of lipoxins, arachidonic‐acid‐derived compounds that promote resolution of inflammation. Lipoxygenases are non‐heme‐iron enzymes that catalyze the peroxidation of polyunsaturated fatty acids. Although all arachidonate‐metabolizing lipoxygenases recognize the same 20‐carbon polyunsaturated fatty acid, each generates a unique product. We describe here the structure of 5‐lipoxygenase, which is distinct among lipoxygenases with respect to the reactions it catalyzes and its regulation. Multiple regulatory mechanisms that combine to ensure a measured generation of its products, precursors of potent signaling compounds, are described. These mechanisms include an atypical (with respect to the lipoxygenase superfamily) protein lability, Ca2+‐induced translocation to the nuclear membrane, and serine phosphorylation.
MetallochaperoneSlyD
Authors: Löw Christian , Stubbs Milton T , Haupt Caroline , Balbach Jochen 
Published: June 2012

AbstractSlyD (sensitive to lysis D) proteins are widely distributed among prokaryotic organisms. They share a two‐domain structure with one FKBP domain and a smaller ‘inserted‐in‐flap’ (IF) domain. Most of the SlyD homologs possess further an unstructured C‐terminal domain harboring metal‐binding properties. All have in common one highly conserved metal‐binding motif at the C‐terminal α‐helix preceding the metal‐binding domain. The single metal‐binding motif and additional metal‐binding sites in specialized domains have been structurally and biochemically characterized. X‐ray and NMR solution structures are available for different homologs showing the unique two‐domain topology and, if present, the additional metal‐binding domain as well as the constitution of the metal‐binding site.
Optimizing Single‐Walled‐Carbon‐Nanotube‐Based Saturable Absorbers for Ultrafast Lasers
Authors: Ferrari Stefania , Bini Marcella , Capsoni Doretta , Galinetto Pietro , Grandi Marco Simone , Griebner Uwe , Steinmeyer Günter , Agnesi Antoniangelo , Pirzio Federico , Ugolotti Elena , Reali Giancarlo , Massarotti Vincenzo 
Published: June 2012

AbstractThe application of single‐walled carbon nanotubes (SWCNTs) as saturable absorbers (SA) in a Nd:glass femtosecond laser is verified as a promising alternative to traditional semiconductor saturable‐absorber mirrors (SESAMs). The shortest laser pulses achieved with a SWCNT‐SA fabricated by the slow‐evaporation method are reported herein. Nearly Fourier‐limited 288 fs pulses are obtained with negative‐dispersion soliton mode‐locking. The importance of the properties of the starting material, such as the degree of purity and the chirality, and the successive slow‐evaporation deposition method is proven by using a multitechnique approach based on X‐ray diffractometry, scanning electron microscopy, and μ‐Raman spectroscopy. The high degree of nanotube alignment on the glass substrate and also the slight metallic character due to electron transfer between the glass matrix and the nanotubes themselves are identified as the main features responsible for the good laser response.
Recent Progress in Non‐Precious Catalysts for Metal‐Air Batteries
Authors: Cao Ruiguo , Lee Jang‐Soo , Liu Meilin , Cho Jaephil 
Published: June 2012

AbstractElectrical energy storage and conversion is vital to a clean, sustainable, and secure energy future. Among all electrochemical energy storage devices, metal‐air batteries have potential to offer the highest energy density, representing the most promising systems for portable (electronics), mobile (electrical vehicles), and stationary (micro‐grids) applications. To date, however, many fundamental issues are yet to be overcome to realize this potential. For example, efficient catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) at the air‐electrode are yet to be developed to significantly reduce the polarization loss in metal‐air batteries, which severely hinders the rate capability, energy efficiency, and operational life. In this progress report, a brief overview is first presented of the critical issues relevant to air‐electrodes in metal‐air batteries. Some recent advancements in the development of non‐precious catalysts for ORR in Li‐air and Zn‐air batteries are then highlighted, including transition metal oxides, low‐dimensional carbon‐based structures, and other catalysts such as transition‐metal macrocycles and metal nitrides. New directions and future perspectives for metal‐air batteries are also outlined.
Increase in the Figure of Merit by Cd‐Substitution in Sn1–xPbxTe and Effect of Pb/Sn Ratio on Thermoelectric Properties
Authors: Han Mi‐Kyung , Zhou Xiaoyuen , Uher Ctirad , Kim Sung‐Jin , Kanatzidis Mercouri G. 
Published: June 2012

AbstractThe effects of Cd‐doping on the thermoelectric properties of Sn1–xPbxTe are investigated and compared to the properties of the corresponding Sn1–xPbxTe solid solutions. The addition of Cd results in a reduction in the carrier concentration and changes in the physical properties, as well as in the conduction type of Sn1–xPbxTe. A significant increase in the power factor accompanied by a reduction in the thermal conductivity result in a higher figure of merit (ZT) for (Sn1–xPbx)0.97Cd0.03Te than that of undoped Sn1–xPbxTe. The maximum ZT (∼0.7) values are observed for p‐type material with x = 0.36 at 560 K. Much higher values (ZT ∼ 1.2 at 560 K for x = 0.73) are obtained on n‐type samples.
An All‐Organic Non‐aqueous Lithium‐Ion Redox Flow Battery
Authors: Brushett Fikile R. , Vaughey John T. , Jansen Andrew N. 
Published: June 2012

AbstractA non‐aqueous lithium‐ion redox flow battery employing organic molecules is proposed and investigated. 2,5‐Di‐tert‐butyl‐1,4‐bis(2‐methoxyethoxy)benzene and a variety of molecules derived from quinoxaline are employed as initial high‐potential and low‐potential active materials, respectively. Electrochemical measurements highlight that the choice of electrolyte and of substituent groups can have a significant impact on redox species performance. The charge‐discharge characteristics are investigated in a modified coin‐cell configuration. After an initial break‐in period, coulombic and energy efficiencies for this unoptimized system are ∼70% and ∼37%, respectively, with major charge and discharge plateaus between 1.8‐2.4 V and 1.7‐1.3 V, respectively, for 30 cycles. Performance enhancements are expected with improvements in cell design and materials processing.
Examination of a genetic algorithm for the application in high‐throughput downstream process development
Authors: Treier Katrin , Berg Annette , Diederich Patrick , Lang Katharina , Osberghaus Anna , Dismer Florian , Hubbuch Jürgen 
Published: June 2012

AbstractCompared to traditional strategies, application of high‐throughput experiments combined with optimization methods can potentially speed up downstream process development and increase our understanding of processes. In contrast to the method of Design of Experiments in combination with response surface analysis (RSA), optimization approaches like genetic algorithms (GAs) can be applied to identify optimal parameter settings in multidimensional optimizations tasks. In this article the performance of a GA was investigated applying parameters applicable in high‐throughput downstream process development. The influence of population size, the design of the initial generation and selection pressure on the optimization results was studied. To mimic typical experimental data, four mathematical functions were used for an in silico evaluation. The influence of GA parameters was minor on landscapes with only one optimum. On landscapes with several optima, parameters had a significant impact on GA performance and success in finding the global optimum. Premature convergence increased as the number of parameters and noise increased. RSA was shown to be comparable or superior for simple systems and low to moderate noise. For complex systems or high noise levels, RSA failed, while GA optimization represented a robust tool for process optimization. Finally, the effect of different objective functions is shown exemplarily for a refolding optimization of lysozyme.
Synthesis and Biological Evaluation of 7‐Alkenyl Homocamptothecins as Potent Topoisomerase I Inhibitors
Authors: Zhu Lingjian , Zhang Xianghua , Lei Ning , Liu Wenfeng , Miao Zhenyuan , Zhuang Chunlin , Sheng Chunquan , Guo Wei , Dong Guoqiang , Yao Jianzhong , Cheng Pengfei , Zhang Wannian 
Published: June 2012

AbstractHomocamptothecin (hCPT) is a camptothecin (CPT) derivative with a seven‐membered β‐hydroxylactone E ring, which shows higher lactone stability and improves topoisomerase I (Topo I) inhibition activity. In an attempt to improve the antitumor activity of homocamptothecins, a series of 7‐alkenyl‐homocamptothecin derivatives was designed and synthesized based on a semisynthetic route starting from CPT. Most of the synthesized compounds exhibit higher cytotoxic activities on the A‐549 tumor cell line than topotecan (TPT). Some compounds such as 2a and 2o show a broad in vitro antitumor spectrum and exhibit superior Topo I‐inhibition activity.
Application of UV/VIS Spectrophotometry and Multivariate Analysis to Characterization of the Species of Solanum sect. ErythrotrichumChild
Authors: Basílio Ionaldo José L. D. , Moura Renata K. P. , Bhattacharyya Jnanabrata , de Fátima Agra Maria 
Published: June 2012

AbstractThe UV/VIS spectral characteristics of the standardized extracts of the leaves of 22 Solanum species of the Leptostemonum clade were investigated in the presence of shift reagents with the aid of multivariate analysis, to obtain data in support of the interspecific and subsectional delimitation proposed for Solanum sect. Erythrotrichum. Of these species, 20 belong to the section Erythrotrichum, S. paniculatum is assigned to the section Torva, and S. robustum is not attributed to a defined section. The results indicated characteristic λmax (absorbance maxima) for each species as well as the presence of phenolic compounds like flavonoids such as 5‐hydroxy flavonols. Hierarchical cluster analysis (HCA) of the data obtained by UV/VIS analysis of the extracts or the extracts with the added shift reagents AlCl3 and HCl showed a cophenetic correlation coefficient above 0.92 and the classification of the data into three groups. The principal‐component analysis (PCA) revealed that the first three principal components accounted for over 98% of the total variance and showed results similar to those obtained by HCA. The present results supported the current proposal for interspecific delimitation of the studied species and partially supported the division of the section into two subsections. The UV/VIS spectral characteristics along with multivariate analysis appear to be a useful approach for distinguishing among species of the genus Solanum.
Chemical and Physical Modulation of Antibiotic Activity in Emericella Species
Authors: de la Cruz Mercedes , Martín Jesús , González‐Menéndez Victor , Pérez‐Victoria Ignacio , Moreno Catalina , Tormo José Rubén , El Aouad Noureddine , Guarro Josep , Vicente Francisca , Reyes Fernando , Bills Gerald F. 
Published: June 2012

AbstractThe addition of epigenetic modifying agents and ion‐exchange resins to culture media and solid‐state fermentations have been promoted as ways to stimulate expression of latent biosynthetic gene clusters and to modulate secondary metabolite biosynthesis. We asked how combination of these treatments would affect a population of screening isolates and their patterns of antibiosis relative to fermentation controls. A set of 43 Emericella strains, representing 25 species and varieties, were grown on a nutrient‐rich medium comprising glucose, casein hydrolysate, urea, and mineral salts. Each strain was grown in untreated agitated liquid medium, a medium treated with suberoylanilide hydroxamic acid, a histone deacetylase inhibitor, 5‐azacytidine, a DNA methylation inhibitor, an Amberlite non‐ionic polyacrylate resin, and the same medium incorporated into an inert static vermiculite matrix. Species‐inherent metabolic differences more strongly influenced patterns of antibiosis than medium treatments. The antibacterial siderophore, desferritriacetylfusigen (1), was detected in most species in liquid media, but not in the vermiculite medium. The predominant antifungal component detected was echinocandin B. Some species produced this antifungal regardless of treatment, although higher quantities were often produced in vermiculite. Several species are reported for the first time to produce echinocandin B (3). A new echinocandin analog, echinocandin E (2), was identified from E. quadrilineata.
Fluid Dynamics of Fluidized and Vibrofluidized Beds Operating with Geldart C Particles
Authors: Meili L. , Daleffe R. V. , Freire J. T. 
Published: June 2012

AbstractThe fluid dynamic behavior of a vibrofluidized bed operating with Geldart C particles was studied. The experiments were conducted in order to observe the influence of amplitude, frequency, and dimensionless vibration number on the minimum fluidization velocity, pressure drop, and standard deviation obtained. It was noted that the dimensionless vibration number should be used very carefully if it is to be the unique parameter to set the vibrational effect of the bed fluid dynamics. The results clearly indicate that the fluid dynamic behavior of the bed is very dependent on the different combinations of amplitude and frequency for the same dimensionless vibration number. Therefore, the use of the amplitude or frequency of vibration and the dimensionless vibration number is recommended for a better characterization of the vibrational effects on the fluid dynamic behavior of the particle bed.
Residence Time Distribution Models Derived from Non‐Ideal Laminar Velocity Profiles in Tubes
Authors: Pegoraro P. R. , Marangoni M. , Gut J. A. W. 
Published: June 2012

AbstractThe theoretical E‐curve for the laminar flow of non‐Newtonian fluids in circular tubes may not be accurate for real tubular systems with diffusion, mechanical vibration, wall roughness, pipe fittings, curves, coils, or corrugated walls. Deviations from the idealized laminar flow reactor (LFR) cannot be well represented using the axial dispersion or the tanks‐in‐series models of residence time distribution (RTD). In this work, four RTD models derived from non‐ideal velocity profiles in segregated tube flow are proposed. They were used to represent the RTD of three tubular systems working with Newtonian and pseudoplastic fluids. Other RTD models were considered for comparison. The proposed models provided good adjustments, and it was possible to determine the active volumes. It is expected that these models can be useful for the analysis of LFR or for the evaluation of continuous thermal processing of viscous foods.
Boronic Acid Functionalized Core–Shell Polymer Nanoparticles Prepared by Distillation Precipitation Polymerization for Glycopeptide Enrichment
Authors: Qu Yanyan , Liu Jianxi , Yang Kaiguang , Liang Zhen , Zhang Lihua , Zhang Yukui 
Published: June 2012

AbstractThe boronic acid‐functionalized core–shell polymer nanoparticles, poly(N,N‐methylenebisacrylamide‐co‐methacrylic acid)@4‐vinylphenylboronic acid (poly(MBA‐co‐MAA)@VPBA), were successfully synthesized for enriching glycosylated peptides. Such nanoparticles were composed of a hydrophilic polymer core prepared by distillation precipitation polymerization (DPP) and a boronic acid‐functionalized shell designed for capturing glycopeptides. Owing to the relatively large amount of residual vinyl groups introduced by DPP on the core surface, the VPBA monomer was coated with high efficiency, working as the shell. Moreover, the overall polymerization route, especially the use of DPP, made the synthesis of nanoparticles facile and time‐saving. With the poly(MBA‐co‐MAA)@VPBA nanoparticles, 18 glycopeptides from horseradish peroxidase (HRP) digest were captured and identified by MALDI‐TOF mass spectrometric analysis, relative to eight glycopeptides enriched by using commercially available meta‐aminophenylboronic acid agarose under the same conditions. When the concentration of the HRP digest was decreased to as low as 5 nmol, glycopeptides could still be selectively isolated by the prepared nanoparticles. Our results demonstrated that the synthetic poly(MBA‐co‐MAA)@VPBA nanoparticles might be a promising selective enrichment material for glycoproteome analysis.
Solvent‐ and Temperature‐Controlled In Situ Ligand Reactions Mediated by CuII and 3′‐[(E)‐{[(1S,2S)‐2‐Aminocyclohexyl]imino}methyl]‐4′‐hydroxy‐4‐biphenylcarboxlic Acid
Authors: Chen Qihui , Jiang Feilong , Chen Lian , Yang Ming , Hong Maochun 
Published: June 2012

AbstractThree new compounds, CuL, CuL′, and Cu2O2L′′2 (H2L=3′‐[(E)‐{[(1S,2S)‐2‐aminocyclohexyl]imino}methyl]‐4′‐hydroxy‐4‐biphenylcarboxlic acid, H2L′=3′‐[(E)‐{[(1S,2S)‐2‐aminocyclohexyl]imino}methyl]‐4′‐hydroxy‐5′‐nitro‐4‐biphenylcarboxlic acid, H2L′′=3′‐(N,N‐dimethylamino methyl)‐4′‐hydroxy‐4‐biphenylcarboxlic acid), were selectively synthesized through a controlled in situ ligand reaction system mediated by copper(II) nitrate and H2L. Selective nitration was achieved by using different solvent mixtures under relatively mild conditions, and an interesting and economical reductive amination system in DMF/EtOH/H2O was also found. All crystal structures were determined by single‐crystal X‐ray diffraction analysis. Both CuL and CuL′ display chiral 1D chain structures, whereas Cu2O2L′′2 possesses a structure with 13×16 Å channels and a free volume of 41.4 %. The possible mechanisms involved in this in situ ligand‐controlled reaction system are discussed in detail.
7‐Decarboxymethyl‐cobyrinates: Vitamin B12‐Derivatives that Lack the c‐Side Chain
Authors: Kräutler Bernhard 
Published: June 2012

AbstractThe synthesis of cobyrinic acid derivatives by reduction of dehydrocobyrinates is largely unexplored. It is, however, a rational path to B12 analogues that lack specific substituents of the corrin moiety of natural B12 derivatives. The partial syntheses of four epimeric 7‐decarboxymethyl‐cobyrinates is described, which is achieved by reduction of Δ7‐dehydro‐7‐de[carboxymethyl]‐cobyrinate with zinc or with the ‘prebiotic’ reducing agent formic acid. A direct and remarkably efficient route was found to 7‐decarboxymethyl‐cobyrinates, which are cobyrinic acid derivatives in which the c‐side chain at ring B of vitamin B12 is missing. The structures of the hexamethyl‐7‐decarboxymethyl‐cobyrinates were characterized and the stereochemical and conformational properties at their newly saturated ring B were analyzed. The stereochemical outcome of the reduction was found to depend strongly on the reaction conditions. In 7‐decarboxymethyl‐cobyrinates, both peripheral carbon centres of ring B carry a hydrogen atom, and the characteristic quaternary carbon centre at C7 of the cobyrinic acid moiety of vitamin B12 is lacking. The still highly substituted 7‐decarboxymethyl‐cobyrinates are readily dehydrogenated in the presence of dioxygen, furnishing 7‐de[carboxymethyl]‐Δ7‐dehydro‐cobyrinate as the common, unsaturated oxidation product. The noted stability of vitamin B12 and of other CoIII‐cobyrinates in the presence of air is a consequence of their highly substituted corrin macrocycle, a finding of interest in the context of chemical rationalizations of the B12 structure.
Algorithms for a strain‐based plasticity criterion for bone
Authors: Pankaj Pankaj , Donaldson Finn E. 
Published: June 2012

SUMMARYA range of stress‐based plasticity criteria have been employed in the finite element analysis of the post‐elastic behaviour of bone. There is some recognition now that strain‐based criteria are more suitable for this material because they better represent its behaviour. Moreover, because bone yields at relatively isotropic strains, a strain‐based criterion requires fewer material parameters unlike those required for a stress‐based criterion. Based on a minimum and maximum principal strain criterion, a robust strain‐based plasticity algorithm is developed. As the criterion comprises six piecewise linear surfaces in principal strain space, it has a number of singular regions. Singularity indicators are developed to direct the algorithm to make appropriate plastic corrector returns when singularity regions are encountered. The developed algorithms permit a plastic corrector to be achieved in a single iterative step in all cases. A range of benchmark tests are developed and conducted after implementing the algorithm in a finite element package. These tests show that the constitutive behaviour is as expected. Copyright © 2012 John Wiley & Sons, Ltd.