bluuebunny/crossref_metadata_2025 huggingface dataset:
One‐Pot Conversion of Carbon Dioxide, Ethylene Oxide, and Amines to 3‐Aryl‐2‐oxazolidinones Catalyzed with Binary Ionic Liquids
Authors: Wang Binshen , Elageed Elnazeer H. M. , Zhang Dawei , Yang Sijuan , Wu Shi , Zhang Guirong , Gao Guohua
Published: December 2013

An effective one‐pot method for the conversion of carbon dioxide, ethylene oxide, and amines to 3‐aryl‐2‐oxazolidinones has been developed. This one‐pot method consists of two parallel reactions and a subsequent cascade reaction between the two products of the corresponding parallel reactions. Notably, the binary ionic liquids of 1‐butyl‐3‐methyl‐imidazolium bromide and 1‐butyl‐3‐methyl‐imidazolium acetate demonstrate a synergistic catalytic effect on this new strategy. 1‐Butyl‐3‐methyl‐imidazolium bromide is essential in two parallel reactions owing to the good nucleophilicity and leaving ability of bromide, and 1‐butyl‐3‐methyl‐imidazolium acetate plays a dominant role in the subsequent cascade reaction owing to the strong basicity of acetate. In addition, the binary ionic liquids can be used thrice without significant loss of catalytic activity.
Functional carbo‐Butadienes: Nonaromatic Conjugation Effects through a 14‐Carbon, 24‐π‐Electron Backbone
Authors: Rives Arnaud , Maraval Valérie , Saffon‐Merceron Nathalie , Chauvin Remi
Published: December 2013

A systematic study of carbo‐butadiene motifs not embedded in an aromatic carbo‐benzene ring is described. Dibutatrienylacetylene (DBA) targets R1C(R)CCC(Ph)C≡CC(Ph)CCC(R)R2 are devised, in which R is C≡CSiiPr3 and R1 and R2 are R, H, or 4‐X‐C6H4, with the latter including three known representatives (X: H, NMe2, or NH2). The synthesis method is based on the SnCl2‐mediated reduction of pentaynediols prepared by early or late divergent strategies; the latter allows access to a OMe–NO2 push–pull diaryl‐DBA. If R1 and R2 are H, an over‐reduced dialkynylbutatriene (DAB) with two allenyl caps was isolated instead of the unsubstituted DBA. If R1=R2=R, the tetraalkynyl‐DBA target was obtained, along with an over‐reduced DBA product with a 12‐membered 1,2‐alkylidene‐1H2,2H2‐carbo‐cyclobutadiene ring. X‐ray crystallography shows that all of the acyclic DBAs adopt a planar trans–transoid–trans configuration. The maximum UV/Vis absorption wavelength is found to vary consistently with the overall π‐conjugation extent and, more intriguingly, with the π‐donor character of the aryl X substituents, which varies consistently with the first (reversible) reduction potential and first (irreversible) oxidation peak, as determined by voltammetry.
Highly Curved Bowl‐Shaped Fragments of Fullerenes: Synthesis, Structural Analysis, and Physical Properties
Authors: Chen Min‐Kuan , Hsin Hsin‐Ju , Wu Tsun‐Cheng , Kang Bo‐Yan , Lee Yen‐Wei , Kuo Ming‐Yu , Wu Yao‐Ting
Published: December 2013

Highly curved buckybowls 3, 4, and 5 were synthesized from planar precursors, fluoranthenes 8, benzo[k]fluoranthenes 10 and naphtho[1,2‐k]‐cyclopenta[cd]fluoranthenes 12, respectively, using straightforward palladium‐catalyzed cyclization reactions. These fluoranthene‐based starting materials were easily prepared from 1,8‐bis(arylethynyl)naphthalenes 6. Both buckybowls 3 and 4 are fragments of C60, whereas 5 is a unique subunit of C70. The curved structures were identified by X‐ray crystallography, and they are deep bowls. The maximum π‐orbital axis vector (POAV) pyramidalization angle in both 3 and 4 is 12.8°. Such a high curvature is very rarely obtained. Buckybowls 5 are less curved than the others because they have a lower density of five‐membered rings, analogous to the tube portion of C70. Cyclopentaannulation increases the bowl depths of 3 and 4, but not the maximum POAV pyramidalization angle. Among the eight buckybowls studied herein, five form polar crystals. The bowl‐to‐bowl inversion dynamics of these buckybowls can be classified into two types; one has a planar transition structure, whereas the other has an S‐shaped transition structure. A larger longitudinal length of these buckybowls corresponds to a stronger preference for the latter. The photophysical properties of these buckybowls were examined and compared with those of C60 and C70. Buckybowls 5 have absorption bands at wavelengths greater than 450 nm, which are similar to those of C70. The chiral resolution of the mono‐substituted buckybowl 4 ac was also studied by using HPLC with a chiral column.
ChemInform Abstract: Bulk Compound Synthesis and Oxygen Deficiency Effect on Electronic and Magnetic Properties of the Zn‐Based Oxyarsenide LaZnAsO1‐δ.
Authors: Wang Xia , Guo Yanfeng , Li Baoe , Tsujimoto Yoshihiro , Yamaura Kazunari
Published: December 2013

Oxygen‐deficient title compounds with 0 ≤ δ ≤ 0.35 are synthesized from stoichiometric amounts of LaAs, ZnO, and Zn (belt‐type high‐pressure apparatus, Au capsule, Ar, 6 GPa, 1300 °C, 2 h).
ChemInform Abstract: Electrochemical Synthesis of Ti5Si3 in CaCl2 Melt.
Authors: Jiao Handong , Wang Qiuyu , Ge Jianbang , Sun Haobo , Jiao Shuqiang
Published: December 2013

The titleompound is prepared by electro‐deoxidation of a TiO2/SiO2 composite in molten CaCl2 electrolyte at 900 °C.
Size Resolved Droplet Velocity Measurements in an Electrostatic Precipitator
Authors: Horender Stefan , Schaub Frank , Sommerfeld Martin
Published: December 2013

Die Partikelgeschwindigkeiten in einem Plattenelektroabscheider wurden mittels eines Phasen‐Doppler‐Anemometers gemessen. Die Seedingtröpfchen zeigten höhere Driftgeschwindigkeiten als aufgrund der Feldwirkung erwartet und bestätigen damit den Einfluss des Ionenwindes. Die relevanten Gradienten der Seedingpartikelkonzentration erhöhten die Driftgeschwindigkeit. Die Wanderungsgeschwindigkeiten der Wassertröpfchen nahmen linear mit der Topfengröße zu und waren ebenso vom Konzentrationsgradienten beeinflusst. Somit konnte die Summe aus Ionenwind und Drift aufgrund der Gradientendiffusion der Tröpfchen abgeschätzt werden.
SEED: solar energy‐aware efficient scheduling for data centers
Authors: Jing Chao , Zhu Yanmin , Li Minglu
Published: December 2013

It is well known that data centers are consuming a large amount of energy that incurs significant financial and environmental costs. Recently, there has been an increasing interest in utilizing green energy for data centers, where green energy sources include solar and wind. This paper studies the crucial problem of maximizing the utilization of green energy through scheduling complex jobs in data centers in order to reduce the use of traditional brown energy. However, it is highly challenging for data centers to make use of green energy. First, the availability of typical green energy is variable to dynamic changes of natural environments, for example, weather. Second, although predictions can be made for the future availability of green energy, it is inevitable that such predictions have errors. Third, jobs are associated with strict deadlines, and it is required that jobs are completed before their deadlines. Finally, because the reliability in a data center relies upon temperature, the awareness of temperature should be taken into account while maximizing the green energy. In this paper, we consider online scheduling of jobs whose arrivals to the data center system dynamically. In addition, we explicitly take the power consumption of switches into account when scheduling jobs onto computing nodes. Two solar energy‐aware algorithms called SEEDMin and SEEDMax have been proposed. Then, we extend SEED to RSEED with the awareness of reliability. To evaluate the effectiveness of the proposed algorithms, comprehensive simulations have been conducted, and the proposed algorithms are compared with other state‐of‐art algorithms. Experimental results demonstrate that both SEEDMin and SEEDMax can significantly increase the utilization of solar energy without violating job deadlines and overall energy budget. The amount of solar energy utilized by SEEDMin and SEEDMax is 33.4%and35.3% larger than that of two traditional scheduling algorithms, MinMin and MinMax, respectively. Also, it can be seen that RSEED greatly improves the reliability by decreasing the temperature. Copyright © 2013 John Wiley & Sons, Ltd.
Poly(ethylene glycol)‐Based Ionic Liquids: Properties and Uses as Alternative Solvents in Organic Synthesis and Catalysis
Authors: Cecchini Martina Maya , Charnay Clarence , De Angelis Francesco , Lamaty Frédéric , Martinez Jean , Colacino Evelina
Published: December 2013

PEG‐based ionic liquids are a new appealing group of solvents making the link between two distinct but very similar fluids: ionic liquids and poly(ethylene glycol)s. They find applications across a range of innumerable disciplines in science, technology, and engineering. In the last years, the possibility to use these as alternative solvents for organic synthesis and catalysis has been increasingly explored. This Review highlights strategies for their synthesis, their physical properties (critical point, glass transition temperature, density, rheological properties), and their application in reactions catalyzed by metals (such as Pd, Cu, W, or Rh) or as organic solvent (for example for multicomponent reactions, organocatalysis, CO2 transformation) with special emphasis on their toxicity, environmental impact, and biodegradability. These aspects, very often neglected, need to be considered in addition to the green criteria usually considered to establish ecofriendly processes.
Growing season net ecosystem CO2 exchange of two desert ecosystems with alkaline soils in Kazakhstan
Authors: Li Longhui , Chen Xi , van der Tol Christiaan , Luo Geping , Su Zhongbo
Published: December 2013

Central Asia is covered by vast desert ecosystems, and the majority of these ecosystems have alkaline soils. Their contribution to global net ecosystem CO2 exchange (NEE) is of significance simply because of their immense spatial extent. Some of the latest research reported considerable abiotic CO2 absorption by alkaline soil, but the rate of CO2 absorption has been questioned by peer communities. To investigate the issue of carbon cycle in Central Asian desert ecosystems with alkaline soils, we have measured the NEE using eddy covariance (EC) method at two alkaline sites during growing season in Kazakhstan. The diurnal course of mean monthly NEE followed a clear sinusoidal pattern during growing season at both sites. Both sites showed significant net carbon uptake during daytime on sunny days with high photosynthetically active radiation (PAR) but net carbon loss at nighttime and on cloudy and rainy days. NEE has strong dependency on PAR and the response of NEE to precipitation resulted in an initial and significant carbon release to the atmosphere, similar to other ecosystems. These findings indicate that biotic processes dominated the carbon processes, and the contribution of abiotic carbon process to net ecosystem CO2 exchange may be trivial in alkaline soil desert ecosystems over Central Asia.
Calpains promote neutrophil recruitment and bacterial clearance in an acute bacterial peritonitis model
Authors: Kumar Vijay , Everingham Stephanie , Hall Christine , Greer Peter A. , Craig Andrew W. B.
Published: December 2013

Activation of the innate immune system is critical for clearance of bacterial pathogens to limit systemic infections and host tissue damage. Here, we report a key role for calpain proteases in bacterial clearance in mice with acute peritonitis. Using transgenic mice expressing Cre recombinase primarily in innate immune cells (fes‐Cre), we generated conditional capns1 knockout mice. Consistent with capns1 being essential for stability and function of the ubiquitous calpains (calpain‐1, calpain‐2), peritoneal cells from these mice had reduced levels of calpain‐2/capns1, and reduced proteolysis of their substrate selenoprotein K. Using an acute bacterial peritonitis model, we observed impaired bacterial killing within the peritoneum and development of bacteremia in calpain knockout mice. These defects correlated with significant reductions in IL‐1α release, neutrophil recruitment, and generation of reactive oxygen species in calpain knockout mice with acute bacterial peritonitis. Peritoneal macrophages from calpain knockout mice infected with enterobacteria ex vivo, were competent in phagocytosis of bacteria, but showed impaired clearance of intracellular bacteria compared with control macrophages. Together, these results implicate calpains as key mediators of effective innate immune responses to acute bacterial infections, to prevent systemic dissemination of bacteria that can lead to sepsis.
Strength of TCR signal from self‐peptide modulates autoreactive thymocyte deletion and Foxp3+Treg‐cell formation
Authors: Caton Andrew J. , Kropf Elizabeth , Simons Donald M. , Aitken Malinda , Weissler Katherine A. , Jordan Martha S.
Published: December 2013

Autoreactive CD4+CD8− (CD4SP) thymocytes can be subjected to deletion when they encounter self‐peptide during their development, but they can also undergo selection to become CD4SPFoxp3+ Treg cells. We have analyzed the relationship between these distinct developmental fates using mice in which signals transmitted by the TCR have been attenuated by mutation of a critical tyrosine residue of the adapter protein SLP‐76. In mice containing polyclonal TCR repertoires, the mutation caused increased frequencies of CD4SPFoxp3+ thymocytes. CD4SP thymocytes expressing TCR Vβ‐chains that are subjected to deletion by endogenous retroviral superantigens were also present at increased frequencies, particularly among Foxp3+ thymocytes. In transgenic mice in which CD4SP thymocytes expressing an autoreactive TCR undergo both deletion and Treg‐cell formation in response to a defined self‐peptide, SLP‐76 mutation abrogated deletion of autoreactive CD4SP thymocytes. Notably, Foxp3+ Treg‐cell formation still occurred, albeit with a reduced efficiency, and the mutation was also associated with decreased Nur77 expression by the autoreactive CD4SP thymocytes. These studies provide evidence that the strength of the TCR signal can play a direct role in directing the extent of both thymocyte deletion and Treg‐cell differentiation, and suggest that distinct TCR signaling thresholds and/or pathways can promote CD4SP thymocyte deletion versus Treg‐cell formation.
Highly Selective H2O2‐Based Oxidation of Alkylphenols to p‐Benzoquinones Over MIL‐125 Metal–Organic Frameworks
Authors: Ivanchikova Irina D. , Lee Ji Sun , Maksimchuk Nataliya V. , Shmakov Alexander N. , Chesalov Yurii A. , Ayupov Artem B. , Hwang Young Kyu , Jun Chul‐Ho , Chang Jong‐San , Kholdeeva Oxana A.
Published: December 2013

The titanium‐based metal–organic framework MIL‐125 and its amine‐functionalized analog, MIL‐125_NH2, have been synthesized and characterized by elemental analysis, XRD, SEM, TEM, N2 adsorption measurements, and spectroscopic techniques, including FTIR, Raman, and DR UV/Vis spectroscopy. Catalytic properties of MIL‐125 and MIL‐125_NH2 were evaluated in the selective oxidation of two representative alkyl‐substituted phenols, 2,3,6‐trimethylphenol and 2,6‐di‐tert‐butylphenol, with the clean oxidant H2O2. With both MIL‐125 and MIL‐125_NH2, the selectivity toward the corresponding p‐benzoquinones was 100 %. Samples of MIL‐125 with different sizes of crystallites (0.5, 1.5, and 5 μm) demonstrated similar reaction rates, thus indicating the absence of diffusion limitations. The efficiency of the oxidant utilization and stability of the MIL‐125 structure increased upon decreasing the amount of water in the reaction mixture. Even if the structural integrity of MIL‐125 was destroyed by the reaction medium, the metal–organic framework acted as a precursor for the highly active, selective, and recyclable catalyst. The MIL‐125‐derived materials were stable toward titanium leaching, behaved as true heterogeneous catalysts, and could easily be recovered by filtration and reused several times without the loss of the catalytic properties.
Phosphorescent C∧C* Cyclometalated PtII Dibenzofuranyl‐NHC Complexes – An Auxiliary Ligand Study
Authors: Tronnier Alexander , Nischan Nicole , Metz Stefan , Wagenblast Gerhard , Münster Ingo , Strassner Thomas
Published: December 2013

Neutral C∧C* cyclometalated PtII NHC complexes have recently emerged as a new class of phosphorescent emitters with high quantum efficiencies, short decay lifetimes and high thermal stability, which makes them promising candidates for OLED applications. Herein, we report investigations on the photophysical properties of seven new PtII complexes containing a chelating NHC dibenzofuranyl ligand (3‐methyl‐1‐dibenzo[b,d]furan‐4‐ylimidazole) and a bidentate monoanionic auxiliary ligand. All complexes have been fully characterized including extensive NMR studies (COSY, HSQC, HMBC, NOESY, 195Pt NMR), three of them also by solid‐state structures. The extraordinary influence of the auxiliary ligands on the photoluminescence properties is demonstrated by quantum yields ranging from 0 % to 91 % in amorphous PMMA films at room temperature. DFT calculations were performed in order to investigate the nature of the emissive states in more detail.
Production of glycerol monolaurate‐enriched monoacylglycerols by lipase‐catalyzed glycerolysis from coconut oil
Authors: Zha Baoping , Chen Zhongwei , Wang Li , Wang Ren , Chen Zhengxing , Zheng Lianhe
Published: December 2013

In order to study the potential of producing glycerol monolaurate (GML) under a mild condition, enzymatic catalyzed glycerolysis in microemulsion system and molecular distillation were used to produce glycerol monolaurate‐enriched MAGs from coconut oil. For the process of glycerolysis, the catalytic abilities of three lipases were compared, and the reaction conditions were studied. Moreover, evaporator temperatures of two‐step molecular distillations were optimized. The results showed that the suitable lipase was Novozym 435, and the optimum glycerolysis parameters were molar ratio of coconut oil to glycerol 1:4; the concentrations of Novozym 435 and sodium (bis‐2‐ethyl‐hexyl) sulfosuccinate 8 and 16%, respectively; and the reaction temperature 50°C. Under these conditions, with a 240 min reaction time, glycerides which contained 62.5% MAGs, 30.4% DAGs, and 5.8% TAGs were obtained. The content of GML was 29.3% and the acid value (AV) was 8.0 mg KOH/g. Then, by two‐step molecular distillations conducted at 90 and 120°C (0.5–1.0 Pa), the content of GML and MAGs were efficiently increased to 60.0 and 97.6%, respectively. Meanwhile, the content of DAGs and the AV were decreased to 2.0% and 0.02 mg KOH/g.

Practical applications: Glycerol monolaurate (GML), a surfactant, has been widely used as emulsifier and preservative in the food industry. However, the traditional production of GML by chemical esterification under high temperature is complicated and energetically costly. The proposed method provideds mild conditions to produce GML. For the first time the GML produced from enzymatic glycerolysis of coconut oil and its concentration by molecular distillation were investigated.
Iodine‐Promoted Oxidative Conversion of o‐Vinyl Diaryl Ketones into o‐Acetyl Diaryl Ketones, Synthesis of 1‐Methyl‐4‐arylphthalazines as Analogues of Podophyllotoxin
Authors: Harikrishna Kommidi , Mukkamala Ramesh , Hinkelmann Bettina , Sasse Florenz , Aidhen Indrapal Singh
Published: December 2013

A new method is described for the metal‐free oxidation of o‐vinyl diaryl ketones in the presence of molecular iodine or N‐iodosuccinimide to give o‐acetyl diaryl ketones. This transformation involves the initial formation of an iodohydrin, and the o‐carbonyl group of the iodohydrin participates in a subsequent rearrangement to give the o‐acetyl diaryl ketone. The presence and participation of ortho‐carbonyl group is necessary for successful conversion. The envisaged 1‐methyl‐4‐arylphthalazines were synthesized from these o‐acetyl diaryl ketones, and their antiproliferative activity on mammalian cell lines was studied.
Fabrication of Fully‐Spray‐Processed Organic Photovoltaic Modules by using an Automated Process in Air
Authors: La Notte Luca , Mineo Daniel , Polino Giuseppina , Susanna Gianpaolo , Brunetti Francesca , Brown Thomas M. , Di Carlo Aldo , Reale Andrea
Published: December 2013

In organic photovoltaics, large‐area‐compatible and solution‐based processes are the best candidates for achieving high throughput at low cost. Among these, spray coating is a well‐established technique in the industry that can be successfully applied to polymer solar cells (PSCs). In this study we report the demonstration of an automated spray process, completely performed in air, to fabricate the first fully spray‐coated modules on glass/transparent‐conducting‐oxide (TCO) substrates. For this purpose we started with optical and electrical characterization of single layers (TiO2, P3HT:PCBM, PEDOT‐CPP, and PEDOT‐PH1000), to obtain films with the desired properties. Then, photovoltaic cells and modules were fabricated by increasing the number of sprayed layers (1‐layer, 2‐layers, and fully sprayed devices completely free from evaporation processes). Good reproducibility and encouraging electrical performances were obtained. In particular, the 1‐layer, 2‐layer, and full modules (active area=6 cm2) exhibited conversion efficiencies of 1.8 %, 1.3 %, and 0.9 %, respectively. Therefore, the feasibility of a scalable and reliable process for spraying all layers of a semitransparent PSC module were demonstrated here with the potential of being applicable to plastic substrates by the introduction of a low‐temperature‐processed layer in place of TiO2.
Uncertainty Analysis of Photovoltaic Power Measurements using Solar Simulators
Authors: Chandel Rahul
Published: December 2013

Solar simulators are the instruments that are used to measure the electrical characteristics of photovoltaic (PV) cells and modules. The PV characteristics are measured at standard test conditions (STC), which are achieved by maintaining an irradiance level of 1000 W m−2, 25 °C temperature, and AM1.5G irradiance spectrum. However, in case of a variation in any of these parameters there will be a deviation in the measured electrical characteristics of the test specimen from standard values. The uncertainties in calibration and measurement system of the simulator can also have significant impacts on power measurements. In this study, an estimation of the uncertainty in the measurements of current, voltage, and power is done by using a polycrystalline silicon PV module and a class A pulsed‐type solar simulator. The results are compared with those obtained from other studies of similar nature to assess the accuracy of measurements. The findings show that if the maximum possible uncertainties are considered for a typical class A simulator, the power measurements can have a variation up to ±3.7 % from the true value for a 68 % confidence level and up to ±9.6 % for a 99 % confidence level.
Biosorption of methylene blue from aqueous solution by poly(amic acid)‐modified chitosan
Authors: Xing Yun , Li Sujuan
Published: December 2013

The purpose of the research was to investigate effects of temperature, initial pH, initial concentration, and contact time on the biosorption of methylene blue (MB) by modified chitosan using a batch technique. The modified chitosan was prepared by grafting poly (amic acid), which was obtained via reaction of pyromellitic dianhydride (PMDA) and l‐arginine, onto the surface of cross‐linked chitosan. The MB sorption process was evaluated at 25, 35, and 45°C. Results showed that the modified chitosan had a good capacity for biosorption of MB. The kinetic behavior was described by pseudo‐second‐order model. The experimental isotherms obtained were fitted better with Langmuir model than Freundlich model. According to the Langmuir equation, the maximum uptake capacity (qm) for MB was 392.16 mg g−1. Thermodynamic parameters
and
were calculated using the Van't Hoff equation, and results showed that MB sorption by modified chitosan was an exothermic and spontaneous process. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 1180–1186, 2014
Stat3 mediates LIF‐induced protection of astrocytes against toxic ROS by upregulating the UPC2 mRNA pool
Authors: Lapp Daniel W. , Zhang Samuel S. , Barnstable Colin J.
Published: December 2013

Reactive oxygen species (ROS) have been implicated in various types of CNS damage, including stroke. We used a cultured astrocyte model to explore mechanisms of survival of CNS cells following ROS damage. We found that pretreatment with leukemia inhibitory factor (LIF) preserves astrocytes exposed to toxic levels of t‐BHP by inhibiting an increase in intracellular ROS following t‐BHP treatment. Astrocytes lacking functional Stat3 did not benefit from the pro‐survival or antioxidant effects of LIF. Inhibition of mitochondrial uncoupling protein 2 (UCP2) using a chemical inhibitor or siRNA abrogates the prosurvival effects of LIF, indicating a critical role for UCP2 in modulation of mitochondrial ROS production in survival following ROS exposure. LIF treatment of astrocytes results in increased UCP2 mRNA that is accompanied by an increase in Stat3 binding to the UCP2 promoter region. Although treatment with LIF alone did not increase UCP2 protein, a combination of LIF treatment and ROS stress led to increased UCP2 protein levels. We conclude that LIF protects astrocytes from ROS‐induced death by increasing UCP2 mRNA, allowing cells to respond to ROS stress by rapidly producing UCP2 protein that ultimately decreases endogenous mitochondrial ROS production. GLIA 2014;62:159–170
Synthesis of isotopically labeled epothilones
Authors: Ganesh Thota , Brodie Peggy J. , Banerjee Abhijit , Bane Susan , Kingston David G. I.
Published: December 2013

The epothilones, including epothilones B and D, are macrocyclic lactones, which have potent cytotoxicities and promote the polymerization of tubulin to mictotubules by binding to and stabilizing the tubulin polymer. They have a very similar mechanism of action to paclitaxel (Taxol®). The determination of the microtubule‐binding conformation of the epothilones is an important piece of information in designing improved analogs for possible clinical use, and internuclear distance information that will assist the determination of this conformation can be obtained by rotational echo double resonance (REDOR) NMR studies of microtubule‐bound epothilones with appropriate stable isotope labels. Analogs of epothilone B and epothilone D with [2H3] and [19F] labels were prepared from an advanced precursor for potential use in REDOR NMR studies to determine internuclear distances in tubulin‐bound ligand. Copyright © 2013 John Wiley & Sons, Ltd.
Immunolocalization of specific beta‐proteins in pad lamellae of the digits in the lizard Anolis carolinensis suggests that cysteine‐rich beta‐proteins provides flexibility
Authors: Alibardi Lorenzo
Published: December 2013

Knowledge of beta‐protein (beta‐keratin) sequences in Anolis carolinensis facilitates the localization of specific sites in the skin of this lizard. The epidermal distribution of two new beta‐proteins (beta‐keratins), HgGC8 and HgG13, has been analyzed by Western blotting, light and ultrastructural immunocytochemistry. HgGC8 includes 16 kDa members of the glycine‐cysteine medium‐rich subfamily and is mainly expressed in the beta‐layer of adhesive setae but not in the setae. HgGC8 is absent in other epidermal layers of the setae and is weakly expressed in the beta‐layer of other scales. HgG13 comprises members of 17‐kDa glycine‐rich proteins and is absent in the setae, diffusely distributed in the beta layer of digital scales and barely present in the beta‐layer of other scales. It appears that the specialized glycine‐cysteine medium rich beta‐proteins such as HgGC8 in the beta‐layer, and of HgGC10 and HgGC3 in both alpha‐ and beta‐layers, are key proteins in the formation of the flexible epidermal layers involved in the function of these modified scales in adaptation to contact and adhesion on surfaces. J. Morphol. 275:504–513, 2014. © 2013 Wiley Periodicals, Inc.
Decrease in horn size and increase in age of trophy sheep in Alberta over 37 years
Authors: Festa‐Bianchet Marco , Pelletier Fanie , Jorgenson Jon T. , Feder Chiarastella , Hubbs Anne
Published: December 2013

Long‐term data (1974–2011) from harvested bighorn rams (Ovis canadensis) in Alberta, Canada, suggested a reduction in horn size and in the proportion of trophy rams in the provincial population over time. Age at harvest increased over time, suggesting slower horn growth. Rams that experienced favorable environmental conditions early in life had rapid horn growth and were harvested at a younger age than rams with slower horn growth. Guided nonresident hunters did not harvest larger rams than residents, suggesting that few large rams were available. Resident hunter success declined in recent years. Despite an apparently stable population, successive cohorts produced a decreasing harvest of trophy rams. We suggest that unrestricted harvest based on a threshold horn size led to a decline in the availability of trophy rams. That decline is partly an inevitable consequence of selective hunting that removes larger rams. Although our analysis does not establish that evolution of smaller horns caused the observed decline in both horn size and harvest of trophy rams, we suggest that intensive trophy hunting may have artificially selected for a decrease in horn growth rate. © 2013 The Wildlife Society.
Development of a preliminary pediatric tracheal growth model from magnetic resonance images
Authors: Amendola Richard L. , Reinhardt Joseph M. , Zimmerman M. Bridget , Sato Yutaka , Diggelmann Henry R. , Kacmarynski Deborah S. F.
Published: December 2013

Objectives/Hypothesis

To develop a growth model of the minimum cross‐sectional area of the normal pediatric trachea with measurements from magnetic resonance images (MRIs) to supplement the clinical criteria used to determine if a child with tracheal stenosis needs surgery.

Study Design

Retrospective imaging review.

Methods

A total of 81 patients were imaged for a variety of clinical reasons and declared to have normal tracheas fully visible in their T1 magnetic resonance image. Regression analysis was used to identify any contribution that age, gender, and z scores for height and weight have in predicting the minimum cross‐sectional area of the trachea.

Results

The best‐fit model for minimum cross‐sectional area is: Area = −0.00451*age4 + 0.177*age3− 2.05*age2 + 12.6*age + 8.02 (area in mm2 and age in years). Gender and z scores for height and weight did not provide any additional explanation of variance in tracheal size.

Conclusions

Our study demonstrates the potential to create a growth model of the normal trachea based on cross‐sectional area of the trachea using MRIs. Even with the relatively small number of patients used to build it, the model has demonstrated some ability to be used as an objective prediction tool when deciding a treatment path for a patient. With continued development of precise, objective measures to diagnose the severity of the tracheal stenosis, more patients can be given early and accurate prognosis and be treated appropriately.

Level of Evidence

4. Laryngoscope, 124:1947–1951, 2014
Practice and Challenges of Building a Semantic Framework for Chemogenomics Research
Authors: Chen Bin , Wild David J.
Published: December 2013

Effective discovery of new drugs for complex diseases demands an integrative analysis of big data aggregated from diverse sources in chemical and biological domains, to help better understand the mechanism of drug actions and to quickly translate discovery to clinical applications. Conventional approaches are confronting critical challenges in the integration of those huge heterogeneous datasets and the rapid transformation from data to knowledge. Semantic technologies aimed at facilitating the building of a common framework that allows data sharing and utilization across applications and domains in the web, have been developed quickly and have been exhibiting a broad impact in life science. Chemogenomics serves as a bridge to connect various chemical and biological data, thus building a semantic framework for chemogenomics research could not only facilitate the development of this field but also advance the intersection among other domains. During the last few years, such framework has been developed and applied in addressing real problems. In the review, we will describe the major techniques needed to build a semantic framework, and will discuss the challenges of having such framework making a broader impact.
Prolonged efficiency of siRNA‐mediated gene silencing in primary cultures of human preadipocytes and adipocytes
Authors: Lee Mi‐Jeong , Pickering R. Taylor , Puri Vishwajeet
Published: December 2013

Objective

Primary human preadipocytes and differentiated adipocytes in culture are valuable cell culture systems to study adipogenesis and adipose function in relation to human adipose biology. To use these systems for mechanistic studies, siRNA‐mediated knockdown of genes for its effectiveness was studied.

Methods

Methods were developed to effectively deliver siRNA for gene silencing in primary preadipocytes isolated from human subcutaneous adipose tissue and newly differentiated adipocytes. Expression level of genes and proteins was measured using quantitative RT‐PCR and western blotting. Lipid droplet morphology was observed using microscopy, and glycerol release was quantified as a measure of lipolysis.

Results

siRNA‐mediated knockdown of genes in primary human preadipocytes resulted in prolonged silencing effects, suppressing genes throughout the process of their differentiation. In newly differentiated adipocytes, siRNA‐mediated gene knockdown allowed proteins to stay depleted for at least 5 days. It was possible to re‐express a protein after its siRNA‐mediated depletion. Importantly, siRNA transfected human adipocytes remained metabolically active, responding to β‐adrenergic stimulation to increase lipolysis.

Conclusions

Our study describes the methods of gene silencing in primary cultures of human preadipocytes and adipocytes and their prolonged effectiveness.
Synthesis of optimal control in a mathematical model of tumour–immune dynamics
Authors: Yegorov I. , Todorov Y.
Published: December 2013

An optimal control problem for a mathematical model of tumour–immune dynamics under the influence of chemotherapy is considered. The toxicity effect of the chemotherapeutic agent on both tumour and immunocompetent cells is taken into account. A standard linear pharmacokinetic equation for the chemotherapeutic agent is added to the system. The aim is to find an optimal strategy of treatment to minimize the tumour volume while keeping the immune response not lower than a fixed permissible level as far as possible. Sufficient conditions for the existence of not more than one switching and not more than two switchings without singular regimes are obtained. The surfaces in the extended phase space, on which the last switching appears, are constructed analytically.Copyright © 2013 John Wiley & Sons, Ltd.
Utilization patterns of Antihyperuricemic Agents Following Safety Announcement on Allopurinol and Benzbromarone by Taiwan Food and Drug Administration
Authors: Cheng Ching‐Lan , Chao Pi‐Huei , Hsu Jason Chih‐Sheng , Weng Maggie Meng‐Yu , On Angela W.F. , Yang Yea‐Huei Kao
Published: December 2013

Objective

The purpose of this study is to evaluate the utilization of four approved antihyperuricemic agents in Taiwan before and after two safety announcements rescinded an indication for allopurinol and added a warning on benzbromarone‐induced hepatotoxicity in the year 2005.

Methods

An interrupted time series design and segmented regression models were used to examine impacts of the safety announcements on the utilization of allopurinol, benzbromarone, probenecid, or sulfinpyrazone. All outpatient prescriptions of the four antihyperuricemic agents were extracted from a longitudinal cohort dataset with 1 000 000 individuals randomly sampled from the National Health Insurance Research Database. We examined utilization patterns of antihyperuricemic agents before and after the policy intervention (i.e., safety announcements and labeling changes of allopurinol and benzbromarone) in the year 2005.

Results

Following the safety announcements, there was a reduction in the number of allopurinol users in the first year of intervention (−95.82 users per 100 000 persons, 95%CI, [−166.84, −24.80]) and a continuous reduction afterward at a rate of −53.17 per 100 000 persons per year. The utilization of benzbromarone grew steadily before 2005 but decreased drastically after the intervention, with a 30.12% reduction in the number of users by the end of year 2008. There was no commensurate change in the number of probenecid or sulfinpyrazone users after the intervention.

Conclusions

Further research is required to evaluate the direct impacts of the safety announcements on clinical outcomes, treatment costs, and patient's quality of life. Copyright © 2013 John Wiley & Sons, Ltd.
Complex Microwave Permittivity of Secondary High Explosives
Authors: Higginbotham Duque Amanda L. , Perry William Lee , Anderson‐Cook Christine M.
Published: December 2013

We aim to understand how microwaves interact with high explosives by studying the complex permittivity from 1–18 GHz of HMX, RDX, TNT, TATB, PETN, Octol, Comp B, 95 % RDX/5 % Viton A (PBX‐RDX), PBX 9404, PBXN‐5, PBXN‐7, PBXW‐14, PBX 9501, and PBX 9502. The combination of a resonant cavity perturbation technique for determining the room‐temperature complex dielectric constant at discrete frequencies and a wide band open circuit method (1–18 GHz) provides an accurate, broadband measurement that describes the dielectric properties in the frequency range of interest. While the values of the real and imaginary permittivity components did not vary significantly as a function of frequency, we found the real part of the permittivity to be highly dependent on relatively small changes in the material density. We used dielectric mixing theory, specifically the linear‐law approximation, to compare the predicted values based on the dielectric properties of individual components with those of the resulting formulation measured experimentally for a select number of samples; the prediction agrees well within the observed variability of the experimentally measured values.
Detection and Identification of Oestrogen‐Active Substances in Plastic Food Packaging Migrates
Authors: Kirchnawy Christian , Mertl Johannes , Osorio Veronica , Hausensteiner Helge , Washüttl Michael , Bergmair Johannes , Pyerin Michael , Tacker Manfred
Published: December 2013

Migrates from plastic food packaging were tested for oestrogen activity by yeast oestrogen screen and subsequently analysed by gas chromatography—mass spectrometry and high‐performance liquid chromatography—mass spectrometry to identify oestrogen‐active chemicals. Plastic samples were migrated according to EC 10/2011 with worst case scenarios being used. Food simulants consisted of either 10–95% ethanol or ultrapure water. Migrates were concentrated afterwards by solid phase extraction. Food contact material tested included polyethylene terephthalate, polypropylene, polyethylene, polystyrene and composite films. Oestrogenic activity ranging from 0.7 to 59 ng/l 17ß‐estradiol equivalents was detected in seven out of 42 samples tested. The highest activity was found in a composite film sample. All 11 polyethylene terephthalate samples tested negative for oestrogen activity. A number of chemicals with known or supposed oestrogen activity were identified in migrates of oestrogen‐active samples. These include butylated hydroxytoluene, 1,3‐diphenylpropane, 1,2‐diphenylcyclobutane and dibutyl phthalate. Copyright © 2013 John Wiley & Sons, Ltd.
Robotic cholecystectomy and resident education: the UC Davis experience
Authors: Nelson Eric C. , Gottlieb Andrea H. , Müller Hans‐Georg , Smith William , Ali Mohamed R. , Vidovszky Tamas J.
Published: December 2013

Introduction

The popularity of robotic surgery highlights the need for strategies to integrate this technique into surgical education. We present 5 year data for robotic cholecystectomy (RC) as a model for training residents.

Methods

Data were collected on all RC over 66 months. Duration for docking the robot (S2) and performing RC (S3), and surgical outcomes, were recorded. We used a linear mixed effects model to investigate learning curves.

Results

Thirty‐eight trainees performed 160 RCs, with most performing more than four. One case was aborted due to haemodynamic instability, and two were converted to open surgery due to adhesions. There were no technical complications. The duration of S2 (mean = 6.2 ± 3.6 min) decreased considerably (p = 0.027). Trainees also demonstrated decrease in duration of S3 (mean = 38.4 ± 15.4 min), indicating improvement in technique (p = 0.008).

Conclusions

RC is an effective model for teaching residents. Significant and reproducible improvement can be realized with low risk of adverse outcomes. Copyright © 2013 John Wiley & Sons, Ltd.
Ring‐Opening Polymerization Reactions of Propylene Oxide Catalyzed by Porphyrin Metal (3+) Complexes of Aluminum, Chromium and Cobalt
Authors: Chatterjee Chandrani , Chisholm Malcolm H.
Published: December 2013

In today's world, a major scientific challenge is preserving the delicate balance between industrial growth and a pollutant free terrestrial environment. Thus, “greener” syntheses of commodity materials, capture and utilization of gaseous industrial by‐products have become research areas of increasing significance. The pioneering work of Inoue showed a potential utilization of CO2, a major petrochemical by‐product, and opened a new field of research. Inoue discovered the (porphyrin)Al(III)X catalyst systems, (X=Cl− or alkoxide) which copolymerize CO2 with epoxides to produce polycarbonates. This catalyst can also copolymerize epoxides and cyclic anhydrides to form polyesters. The current record describes our research aimed towards mechanistic understanding and further developments of (porphyrin)M(III)X catalyst systems. This detailed account shows the influence of the porphyrin ligands (tetraphenylporphyrin (TPP), octaethylporphyrin (OEP), tetrakis‐pentafluorophenylporphyrin (TFPP)), metal centers (Al, Cr, and Co) and Lewis base co‐catalysts on the individual reaction steps and equilibria involved in the copolymerization processes.
TNF‐α mediates mitochondrial uncoupling and enhances ROS‐dependent cell migration via NF‐κB activation in liver cells
Authors: Kastl L. , Sauer S.W. , Ruppert T. , Beissbarth T. , Becker M.S. , Süss D. , Krammer P.H. , Gülow K.
Published: December 2013

Development of hepatocellular carcinoma (HCC) is accompanied by a continuous increase in reactive oxygen species (ROS) levels. To investigate the primary source of ROS in liver cells, we used tumor necrosis factor‐alpha (TNF‐α) as stimulus. Applying inhibitors against the respiratory chain complexes, we identified mitochondria as primary source of ROS production. TNF‐α altered mitochondrial integrity by mimicking a mild uncoupling effect in liver cells, as indicated by a 40% reduction in membrane potential and ATP depletion (35%). TNF‐α‐induced ROS production activated NF‐κB 3.5‐fold and subsequently enhanced migration up to 12.7‐fold. This study identifies complex I and complex III of the mitochondrial respiratory chain as point of release of ROS upon TNF‐α stimulation of liver cells, which enhances cell migration by activating NF‐κB signalling.
Identification of the Phosphorylated Residues in TveIF5A by Mass Spectrometry
Authors: Quintas-Granados Laura Itzel , López-Camarillo César , Armas Jesús Fandiño , Mendoza Hernandez Guillermo , Alvarez-Sánchez María Elizbeth
Published: December 2013

The initiation factor eIF5A in Trichomonas vaginalis (TveIF5A) is previously shown to undergo hypusination, phosphorylation and glycosylation. Three different pI isoforms of TveIF5A have been reported. The most acidic isoform (pI 5.2) corresponds to the precursor TveIF5A, whereas the mature TveIF5A appears to be the most basic isoform (pI 5.5). In addition, the intermediary isoform (pI 5.3) is found only under polyamine-depleted conditions and restored with exogenous putrescine. We propose that differences in PI are due to phosphorylation of the TveIF5A isoforms. Here, we have identified phosphorylation sites using mass spectrometry. The mature TveIF5A contains four phosphorylated residues (S3, T55, T78 and T82). Phosphorylation at S3 and T82 is also identified in the intermediary TveIF5A, while no phosphorylated residues are found in the precursor TveIF5A. It has been demonstrated that eIF5A proteins from plants and yeast are phosphorylated by a casein kinase 2 (CK2). Interestingly, a gene encoding a protein highly similar to CK2 (TvCK2) is found in T. vaginalis, which might be involved in the phosphorylation of TveIF5A in T. vaginalis.
Screening Preeclamptic Cord Plasma for Proteins Associated with Decreased Breast Cancer Susceptibility
Authors: Low Hoi Pang , Tiwari Ashutosh , Janjanam Jagadeesh , Qiu Li , Chang Chien-I , Strohsnitter William C. , Norwitz Errol R. , Tam Sun W. , Evans James E. , Green Karin M. , Paulo Joao A. , Lambe Mats , Hsieh Chung-Cheng
Published: December 2013

Preeclampsia, a complication of pregnancy characterized by hypertension and proteinuria, has been found to reduce the subsequent risk for breast cancer in female offspring. As this protective effect could be due to exposure to preeclampsia-specific proteins during intrauterine life, the proteomic profiles of umbilical cord blood plasma between preeclamptic and normotensive pregnancies were compared. Umbilical cord plasma samples, depleted of 14 abundant proteins, were subjected to proteomic analysis using the quantitative method of nanoACQUITY ultra performance liquid chromatography–mass spectrometry with elevated energy mode of acquisitionE (NanoUPLC-MSE). Sixty-nine differentially expressed proteins were identified, of which 15 and 6 proteins were only detected in preeclamptic and normotensive pregnancies, respectively. Additionally, expression of 8 proteins (gelsolin, complement C5, keratin type I cytoskeletal 10, pigment epithelium-derived factor, complement factor B, complement component C7, hemoglobin subunit gamma-2 and alpha-fetoprotein) were up-regulated in preeclampsia with a fold change of ⩾2.0 when compared to normotensive pregnancies. The identification of alpha-fetoprotein in preeclamptic umbilical cord blood plasma supported the validity of this screen as alpha-fetoprotein has anti-estrogenic properties and has previously been linked to preeclampsia as well as a reduced breast cancer risk. The findings of this pilot study may provide new insights into the mechanistic link between preeclampsia and potentially reduced breast cancer susceptibility in adult life.
Use of the “obstetric shock index” as an adjunct in identifying significant blood loss in patients with massive postpartum hemorrhage
Authors: Le Bas Abigail , Chandraharan Edwin , Addei Anthony , Arulkumaran Sabaratnam
Published: December 2013

Objective

To establish the normal range for the “obstetric shock index” (OSI) after birth and to determine its usefulness as an aid to estimate blood loss in postpartum hemorrhage (PPH).

Methods

A retrospective case–control analysis was conducted involving pregnant women admitted to St Georges Hospital for delivery: 50 with no PPH (control group) and 50 with massive PPH (> 30% loss of blood volume; case group). The OSI was calculated at 10 and 30 minutes from PPH onset.

Results

Mean OSI in the control group at 10 and 30 minutes was 0.74 (range, 0.4–1.1) and 0.76 (range, 0.5–1.1), respectively. In the case group, mean OSI at 10 and 30 minutes was 0.91 (range, 0.4–1.5) and 0.90 (range, 0.5–1.4), respectively, with 64% requiring blood products. In the case group, 89% of women with an OSI of 1.1 or more at 10 minutes required transfusion; 75% with an OSI of 1.1 or more at 30 minutes required transfusion.

Conclusion

We recommend that the normal OSI range should be 0.7–0.9. An OSI of more than 1 seems to be a useful adjunct in estimating blood loss in cases of massive PPH and in predicting the need for blood and blood products.