bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Facile Synthesis of Benzimidazolin‐2‐chalcogenones: Nature of the Carbon—Chalcogen Bond.
Authors: Manjare Sudesh T. , Sharma Sagar , Singh Harkesh B. , Butcher Ray J.
Published: March 2013

The target compounds are prepared using Na2E2 (E=S, Se, Te) under basic conditions [cf.
ChemInform Abstract: Catalysis‐Based Enantioselective Total Synthesis of Myxothiazole Z, (14S)‐Melithiazole G and (14S)‐Cystothiazole F.
Authors: Colon Aude , Hoffman Thomas J. , Gebauer Julian , Dash Jyotirmayee , Rigby James H. , Arseniyadis Stellois , Cossy Janine
Published: March 2013

Melithiazole G (VII) is prepared via a sequence involving cross‐metathesis of alkenes (I) and (II), asymmetric transfer hydrogenation of olefin (IV), and Stille coupling reaction of bromide (III) as the key steps.
ChemInform Abstract: Mechanical Activation of Al‐Oxyhydroxide Minerals ‐ Physicochemical Changes, Reactivity and Relevance to Bayer Process
Authors: Alex T. C. , Kumar Rakesh , Roy S. K. , Mehrotra S. P.
Published: March 2013

Review: 34 refs.
ChemInform Abstract: Ceramic Integration Technologies for Solid Oxide Fuel Cells
Authors: Schilm Jochen , Rost Axel , Poenicke Andreas , Kusnezoff Mihails , Michaelis Alexander
Published: March 2013

Review: 52 refs.
ChemInform Abstract: The Chemistry of Group‐VIb Metal Carbonyls
Authors: Kaushik Manish , Singh Ayodhya , Kumar Munesh
Published: March 2013

Review: 296 refs.
ChemInform Abstract: Gold—Alkene Complexes
Authors: Cinellu Maria Agostina
Published: March 2013

Review: 90 refs.
ChemInform Abstract: Catalytic, Mild, and Selective Oxyfunctionalization of Linear Alkanes: Current Challenges.
Authors: Bordeaux Melanie , Galarneau Anne , Drone Jullien
Published: March 2013

Review: 166 refs.
ChemInform Abstract: Catalytic Selective Synthesis
Authors: Mahatthananchai Jessada , Dumas Aaron M. , Bode Jeffrey W.
Published: March 2013

Review: 224 refs.
ChemInform Abstract: Ionic Liquids as (Co‐)solvents and Co‐catalysts for Organocatalytic Reactions
Authors: Toma Stefan , Sebesta Radovan
Published: March 2013

Review: 91 refs.
ChemInform Abstract: Physical and Photochemical Properties of Macrocyclic Azobenzenes
Authors: Norikane Yasuo
Published: March 2013

Review: 29 refs.
ChemInform Abstract: From Zeozymes to Bioinspired Heterogeneous Solids: Evolution of Design Strategies for Sustainable Catalysis
Authors: Xuereb David J. , Dzierzak Joanna , Raja Robert
Published: March 2013

Review: 97 refs.
ChemInform Abstract: Structural Concepts of Novel Supramolecular Proton Transfer Compounds and Their Metal Complexes. Part 2.
Authors: Mirzaei M. , Aghabozorg H. , Eshtiagh‐Hosseini H.
Published: March 2013

Review: 108 refs.
ChemInform Abstract: The Invention of Immersion Ultramicroscopy in 1912 — The Birth of Nanotechnology?
Authors: Mappes Timo , Jahr Norbert , Csaki Andrea , Vogler Nadine , Popp Juergen , Fritzsche Wolfgang
Published: March 2013

Review: [43 refs.]
ChemInform Abstract: Ceramics in Environmental Catalysis: Applications and Possibilities
Authors: Labhsetwar Nitin , Doggali P. , Rayalu S. , Yadav R. , Mistuhashi T. , Haneda H.
Published: March 2013

Review: 57 refs.
ChemInform Abstract: Low Band Gap Polycyclic Hydrocarbons: From Closed‐Shell Near Infrared Dyes and Semiconductors to Open‐Shell Radicals
Authors: Sun Zhe , Ye Qun , Chi Chunyan , Wu Jishan
Published: March 2013

Review: ca. 200 refs.
Enantiomeric Separation of Original Heterocyclic Organophosphorus Compounds in Supercritical Fluid Chromatography
Authors: West Caroline , Cieslikiewicz‐Bouet Monika , Lewinski Krzysztof , Gillaizeau Isabelle
Published: March 2013

New and original heterocyclic α‐enamido phosphine chiral solutes were prepared: four structurally similar racemates with the chirality center placed on the phosphorus atom, and four other related pairs of enantiomers with chirality borne by the carbon atoms of the phospholane ring. The structural variations were placed on an aliphatic heterocycle (six‐ or seven‐member rings) and on the carbamate function (methyl or t‐butyl). Their separation was achieved on a commercial cellulose tris‐(3,5‐dimethylphenylcarbamate) stationary phase (Lux Cellulose‐1, Phenomenex) in supercritical fluid chromatography (SFC). The effects of molecular structure on SFC retention and enantioresolution were studied. Among these eight pairs of enantiomers, some reversal of elution order between similar compounds was observed. The effect of changing the organic solvent (methanol and ethanol) and its proportion (between 5 and 40%) in the mobile phase was investigated. Retention data were collected over the temperature range 0–50 °C, and the results interpreted from thermodynamic aspects. Chirality, 2013. © 2013 Wiley Periodicals, Inc.
Pesticide Residues in the Danube River Basin in Serbia – a Survey during 2009–2011
Authors: Antić Nikolina , Radišić Marina , Radović Tanja , Vasiljević Tatjana , Grujić Svetlana , Petković Anđelka , Dimkić Milan , Laušević Mila
Published: March 2013

In this work, a total of 38 pesticides was monitored in the Danube River Basin in Serbia during ten sampling campaigns in 2009, 2010, and 2011. The quantification of analytes was performed using procedures based on solid‐phase extraction (SPE) followed by LC–MS/MS or GC–MS. In general, low pesticide levels were found, except for the samples collected during May–June of 2010 and June of 2011. During this period, pesticide application is high and rainfall was described as extremely above normal or above normal, leading to very pronounced runoff and very high detected pesticide levels. At the sampling site Smederevo (the Danube River), high concentrations of terbuthylazine (200 ng L−1) and metolachlor (150 ng L−1) were found. In the Danube tributary Morava, high concentrations of carbendazim (269 ng L−1), atrazine (188 ng L−1), terbuthylazine (180 ng L−1), and acetochlor (110 ng L−1) were detected, while in the tributary Tisa only terbuthylazine was present at high levels (130 ng L−1). In other sampling campaigns, pesticides were present at low concentrations. The most frequently found pesticide was carbendazim, probably due to slow degradation rate in environment.
Hepatic manifestations of metabolic syndrome
Authors: Medina‐Santillán Roberto , López‐Velázquez Jorge A. , Chávez‐Tapia Norberto , Torres‐Villalobos Gonzalo , Uribe Misael , Méndez‐Sánchez Nahum
Published: March 2013

The prevalence of metabolic syndrome is growing around the world at an alarming rate. Obesity involves a plethora of molecules that predispose individuals to an inflammatory state and various metabolic complications. Dysregulation of nutrient metabolism is a key step during the progression of chronic liver disease that induces an inflammatory state, cellular damage, and impaired hepatic insulin signaling, which leads to insulin resistance. Insulin resistance arises from multiple defects in the liver, adipose tissues, and muscle signaling, which leads to a failure to suppress hepatic gluconeogenesis and glycogenolysis, thereby enhancing fat accumulation in the hepatocytes via increased lipolysis and increased hepatic synthesis of triglycerides. This metabolic condition also increases the frequency of other comorbidities such as liver and biliary diseases. Nonalcoholic fatty liver disease is the hepatic expression of metabolic syndrome, which comprises a spectrum of clinical and histological events ranging from simple and benign fatty liver to steatohepatitis, which is characterized by the abnormal activation of pathways leading to an aggressive inflammatory condition. This pathological state may progress to more severe damage known as cirrhosis, which endangers the anatomy and function of liver tissue. In addition, a small group of patients with end‐stage liver disease may develop hepatocellular carcinoma and finally death. By contrast, cholesterol gallstone disease is a common metabolic disease, and is considered to be the main biliary indicator of metabolic syndrome. This review provides a detailed summary of the hepatic manifestations associated with metabolic syndrome. Copyright © 2013 John Wiley & Sons, Ltd.
Commentary on ‘Behavioural and cognitive‐behavioural group‐based parenting programmes for early‐onset conduct problems in children aged 3 to 12 years’
Authors: Haroon Munib
Published: March 2013

This is a commentary on a Cochrane review, published in this issue of EBCH, first published as: Furlong M, McGilloway S, Bywater T, Hutchings J, Smith SM, Donnelly M. Behavioural and cognitive‐behavioural group‐based parenting programmes for early‐onset conduct problems in children aged 3 to 12 years. Cochrane Database of Systematic Reviews 2012, Issue 2. Art. No.: CD008225. DoI: 10.1002/14651858.CD008225.pub2.
Long‐distance dispersal in a fire‐ and livestock‐protected savanna
Authors: Tarazi Roberto , Sebbenn Alexandre M. , Kageyama Paulo Y. , Vencovsky Roland
Published: March 2013

Savannas are highly diverse and dynamic environments that can shift to forest formations due to protection policies. Long‐distance dispersal may shape the genetic structure of these new closed forest formations. We analyzed eight microsatellite loci using a single‐time approach to understand contemporary pollen and effective seed dispersal of the tropical tree, Copaifera langsdorffii Desf. (Fabaceae), occurring in a Brazilian fire‐ and livestock‐protected savanna. We sampled all adult trees found within a 10.24 ha permanent plot, young trees within a subplot of 1.44 ha and open‐pollinated seeds. We detected a very high level of genetic diversity among the three generations in the studied plot. Parentage analysis revealed high pollen immigration rate (0.64) and a mean contemporary pollen dispersal distance of 74 m. In addition, half‐sib production was 1.8 times higher than full‐sibs in significant higher distances, indicating foraging activity preference for different trees at long distances. There was a significant and negative correlation between diameter at breast height (DBH) of the pollen donor with the number of seeds (r = −0.640, P‐value = 0.032), suggesting that pollen donor trees with a higher DBH produce less seeds. The mean distance of realized seed dispersal (recruitment kernel) was 135 m due to the large home range dispersers (birds and mammals) in the area. The small magnitude of spatial genetic structure found in young trees may be a consequence of overlapping seed shadows and increased tree density. Our results show the positive side of closed canopy expansion, where animal activities regarding pollination and seed dispersal are extremely high.
Influence of hydrogenation and antioxidants on the stability of soybean oil biodiesels
Authors: Alexandrino Cristiane D. , Morais Selene M. , Oliveira Micheline S. C. , Machado Lyeghyna K. A. , Martins Clécio G. , Craveiro Afrânio A. , Rocha Naele C. , Valle Camila P. , Malveira Jackson Q. , Jorge Fernando A. S.
Published: March 2013

This study examined the influence of hydrogenation and antioxidant activity of natural products derived from Mangifera indica on soybean biodiesel stability. Biodiesels were prepared with refined, semi‐refined, and partially hydrogenated soybean oil and the stability was evaluated in a Rancimat apparatus. The biodiesel from partially hydrogenated soybean oil showed greater stability (11.9 h), exceeding the standard limit established by the Brazilian National Petroleum Agency (6 h). Gallic acid, tannic acid, and mango seed kernel extract were evaluated as antioxidants. The gallic acid showed higher antioxidant ability than the other products, increasing twofold the oxidative stability (20.8 h). The results indicate the importance of mango seed as a source of efficient antioxidants for biodiesel just like gallic acid.

Practical applications: The results provide detailed information about: (i) the influence of hydrogenation on soybean biodiesel stability; (ii) the antioxidant activity of natural products derived from M. indica; (iii) and the importance of each phenolic constituent on the stability. Mango seed is an abundant waste product from fruit juice industry in Brazil and could be used for obtaining an effective antioxidant additive for biodiesel.
Chiral Aminated α‐Methylenebenzocycloalkenes from o‐Bromoaryl Aldehydes and Ketones
Authors: Sirvent Juan Alberto , Foubelo Francisco , Yus Miguel
Published: March 2013

Chiral tert‐butylsulfinyl imines 3, which are easily prepared from the corresponding bromo carbonyl compounds 1 and tert‐butanesulfinamide (2), undergo a diastereoselective allylation by using indium metal and allyl bromide to give the corresponding homoallyl sulfinylamines 4. Treatment of compounds 4 with a catalytic amount of palladium acetate and triphenylphosphane gives exo‐methylene‐substitutedsulfinylamino)benzocycloalkenes 5 (five‐ to seven‐membered rings) that are easily deprotected with hydrochloric acid to give chiral primary amines 6.
Sequential Fullerenylation of Bis‐malonates – Efficient Access to Oligoclusters with Different Fullerene Building Blocks
Authors: Wasserthal Lennard K. , Kratzer Andreas , Hirsch Andreas
Published: March 2013

A method for the sequential fullerenylation of bis‐malonates with parent C60 and C2v‐symmetric pentakis‐adducts is reported. This approach relies on the finding that (a) chloromalonates can be used for the nucleophilic cyclopropanation of [6,6] double bonds of C60, and (b) chloromalonates, in contrast to bromomalonates, do not undergo base‐catalyzed halogen exchange reactions. For the proof of concept, we synthesized a heptafullerene by using a divergent approach based on a fullerene hexakis‐adduct with six bis‐malonate addends in octahedral positions, each of which is suitable for an additional cyclopropanation of a fullerene building block.
Mechanical Characteristics of Electrolytes Assessed with Resonant Ultrasound Spectroscopy
Authors: Araki W. , Azuma H. , Yota T. , Arai Y. , Malzbender J.
Published: March 2013

Elastic properties and residual stresses are critical for the assessment of the reliability of ceramics components. The thin electrolyte layer of anode supported SOFCs is under a state of high compressive residual stress. In the present study, the elastic properties of this layer as well as the residual stress distribution induced in the anode‐supported planar SOFC cell were examined by using the resonant ultrasound spectroscopy (RUS). A modal analysis by finite element simulation demonstrated that the RUS has a great potential to determine these mechanical characteristics. The Young's modulus can be determined from the natural frequencies of the layered sample whilst the residual stress can be determined using the sample with a semi‐hole. Estimates of the Poisson's ratio are possible. In the experiment, various individual resonant oscillations were successfully identified using the present RUS system. Hence, by comparison of experimental results and simulations, the elastic properties as well as the residual stress were obtained. Although the proposed method is still experimentally challenging, it could be developed to become a powerful tool to simultaneously determine residual stresses and elastic constants of thin‐layered systems.
Numerical simulations on megathrust rupture stabilized under strong dilatancy strengthening in slow slip region
Authors: Liu Yajing
Published: March 2013

Episodic slow slip events (SSEs) typically involve a few millimeters to centimeters of slip over several days to months at depths near or further downdip of megathrust seismogenic zones. Despite its widespread presence in subduction margins, it remains unknown how SSEs interact with the seismogenic zone and affect megathrust ruptures. Here, I construct a 2‐D thrust fault model governed by rate‐state friction to investigate how fault dilatancy influences the amplitude and spatial distribution of‘ coseismic slip, afterslip, and SSEs. Model results illustrate that, under strong dilatancy and high pore pressure around the friction stability transition, coseismic rupture stops at the onset of SSEs. Modeled SSEs have lower velocities, longer recurrence intervals and durations, and larger slip amounts as dilatancy becomes stronger, demonstrating a transition from short‐term to long‐term type of SSE behavior. These results qualitatively explain the range of spatial distributions of SSEs and megathrust ruptures observed or inferred in natural subduction zones. Furthermore, the relative depths of SSEs and megathrust afterslip may serve as an indicator of dilatancy effectiveness.
Impact of primary biliary cirrhosis on perceived quality of life: The UK-PBC national study
Authors: Mells George F. , Pells Greta , Newton Julia L. , Bathgate Andrew J. , Burroughs Andrew K. , Heneghan Michael A. , Neuberger James M. , Day Darren B. , Ducker Samantha J. , Sandford Richard N. , Alexander Graeme J. , Jones David E.J.
Published: March 2013

Primary biliary cirrhosis (PBC) has a complex clinical phenotype, with debate about the extent and specificity of frequently described systemic symptoms such as fatigue. The aim of this study was to use a national patient cohort of 2,353 patients recruited from all clinical centers in the UK to explore the impact of disease on perceived life quality. Clinical data regarding diagnosis, therapy, and biochemical status were collected and have been reported previously. Detailed symptom phenotyping using recognized and validated symptom assessment tools including the PBC-40 was also undertaken and is reported here. Perception of poor quality of life and impaired health status was common in PBC patients (35% and 46%, respectively) and more common than in an age-matched and sex-matched community control group (6% and 15%, P < 0.0001 for both). Fatigue and symptoms of social dysfunction were associated with impaired perceived quality of life using multivariate analysis. Fatigue was the symptom with the greatest impact. Depression was a significant factor, but appeared to be a manifestation of complex symptom burden rather than a primary event. Fatigue had its greatest impact on perceived quality of life when accompanied by symptoms of social dysfunction, suggesting that maintenance of social networks is critical for minimizing the impact of fatigue. Conclusion: The symptom burden in PBC, which is unrelated to disease severity or ursodeoxycholic acid response, is significant and complex and results in significant quality of life deficit. The complexity of symptom burden, and its lack of relation to disease severity and treatment response, suggest that specific approaches to symptom management are warranted that address both symptom biology and social impact. (Hepatology 2013;58:-)
Interferon Regulatory Factor 9 Protects Against Hepatic Insulin Resistance and Steatosis in Male Mice
Authors: Wang Xin-An , Zhang Ran , Jiang Dingsheng , Deng Wei , Zhang Shumin , Deng Shan , Zhong Jinfeng , Wang Tao , Zhu Li-Hua , Yang Li , Hong Shufen , Guo Sen , Chen Ke , Zhang Xiao-Fei , She Zhigang , Chen Yingjie , Yang Qinglin , Zhang Xiao-Dong , Li Hongliang
Published: March 2013

Obesity is a calorie-excessive state associated with high risk of diabetes, atherosclerosis, and certain types of tumors. Obesity may induce inflammation and insulin resistance (IR). We found that the expression of interferon (IFN) regulatory factor 9 (IRF9), a major transcription factor mediating IFN responses, was lower in livers of obese mice than in those of their lean counterparts. Furthermore, whole-body IRF9 knockout (KO) mice were more obese and had aggravated IR, hepatic steatosis, and inflammation after chronic high-fat diet feeding. In contrast, adenoviral-mediated hepatic IRF9 overexpression in both diet-induced and genetically (

ob/ob

) obese mice showed markedly improved hepatic insulin sensitivity and attenuated hepatic steatosis and inflammation. We further employed a yeast two-hybrid screening system to investigate the interactions between IRF9 and its cofactors. Importantly, we identified that IRF9 interacts with peroxisome proliferator-activated receptor alpha (PPAR-α), an important metabolism-associated nuclear receptor, to activate PPAR-α target genes. In addition, liver-specific PPAR-α overexpression rescued insulin sensitivity and ameliorated hepatic steatosis and inflammation in IRF9 KO mice.

Conclusion

: IRF9 attenuates hepatic IR, steatosis, and inflammation through interaction with PPAR-α. (Hepatology 2013;58:603–616)
New horizons in hepatitis C antiviral therapy with direct-acting antivirals
Authors: Aghemo Alessio , De Francesco Raffaele
Published: March 2013

Most direct-acting antivirals (DAAs) that are being developed as therapy against hepatitis C virus target the NS3/4A protease, the NS5A protein, and the NS5B polymerase. The latter enzyme offers different target sites: the catalytic domain for nucleos(t)ide analogues as well as a number of allosteric sites for nonnucleos(t)ide inhibitors. Two NS3/4A protease inhibitors have been approved recently, and more than 40 new NS3/4A, NS5A, or NS5B inhibitors are in development. These agents can achieve very high cure rates when combined with pegylated interferon-β and ribavirin and show promising clinical results when administered in all-oral combinations. In addition to the more canonical drug targets, new alternative viral targets for small-molecule drug development are emerging, such as p7 or NS4B and viral entry. Future research will need to define well-tolerated and cost-effective DAA combinations that provide the highest rates of viral eradication in all patients (including those with advanced liver disease), the broadest spectrum of action on viral genotypes showing minimal or no clinical resistance, and the shortest treatment duration. (Hepatology 2013)
High Incidence of Treatment-Induced And Vaccine-Escape Hepatitis B Virus Mutants Among Human Immunodeficiency Virus/Hepatitis B–Infected Patients
Authors: Lacombe Karine , Boyd Anders , Lavocat Fabien , Pichoud Christian , Gozlan Joel , Miailhes Patrick , Lascoux-Combe Caroline , Vernet Guy , Girard Pierre-Marie , Zoulim Fabien
Published: March 2013

Anti–hepatitis B virus (HBV) nucleos(t)ides analogs (NA) exert selective pressures on polymerase (pol) and surface (S) genes, inducing treatment resistance and increasing the risk of vaccine escape mutants. The rate of emergence for these mutations is largely unknown in patients coinfected with human immunodeficiency virus (HIV) and HBV undergoing dual-active therapy. In a 3-year, repeat-sampling, prospective cohort study, HBV viral genome sequences of 171 HIV-HBV coinfected patients, presenting with HBV viremia for at least one visit, were analyzed every 12 months via DNA chip. Logistic and Cox proportional hazard models were used to determine risk factors specifically for S gene mutations at baseline and during follow-up, respectively. HBV-DNA levels >190 IU/mL substantially decreased from 91.8% at inclusion to 40.3% at month 36 (P < 0.001), while lamivudine (LAM) or emtricitabine (FTC) use remained steady (71.9%) and tenofovir (TDF) use expanded (month 0, 17.5%; month 36, 66.7%; P < 0.001). The largest increase of any mutation class was observed in l-nucleoside–associated pol gene/antiviral-associated S gene mutations (cumulative incidence at the end of follow-up, 17.5%) followed by alkyl phosphonate-associated pol-gene (7.4%), immune-associated S gene (specifically any amino acid change at positions s120/s145, 6.4%), and d-cyclopentane–associated pol-gene mutations (2.4%). Incidence of l-nucleoside–associated pol-gene/antiviral–associated S gene mutations was significantly associated with concomitant LAM therapy (adjusted hazard ratio [HR], 4.61; 95% confidence interval [CI], 1.36-15.56), but inversely associated with TDF use (adjusted HR/month, 0.94; 95% CI,0.89-0.98). Cumulative duration of TDF was significantly associated with a reduction in the occurrence of immune-associated S gene mutations (HR/month, 0.88; 95% CI, 0.79-0.98). No major liver-related complications (e.g., fulminant hepatitis, decompensated liver, and hepatocellular carcinoma) were observed in patients with incident mutations. Conclusion: Vaccine escape mutants selected by NA exposure were frequent and steadily increasing during follow-up. Although the high antiviral potency of TDF can mitigate incident mutations, other antiviral options are limited in this respect. The public health implications of their transmission need to be addressed. (Hepatology 2013;53:912–922)
Diel patterns in coastal‐stream nitrate concentrations linked to evapotranspiration in the riparian zone of a low‐relief, agricultural catchment
Authors: Flewelling Samuel A. , Hornberger George M. , Herman Janet S. , Mills Aaron L. , Robertson Wendy M.
Published: March 2013

Evapotranspiration (ET) can cause diel fluctuations in the elevation of the water table and the stage in adjacent streams. The diel fluctuations of water levels change head gradients throughout the day, causing specific discharge through near‐stream sediment to fluctuate at the same time scale. In a previous study, we showed that specific discharge controls the residence time of groundwater in streambed sediment that, in turn, exerted the primary control on removal from groundwater passing through the streambed. In this study, we examine the magnitude of diel specific discharge patterns through the streambed driven by ET in the riparian zone with a transient numerical saturated–unsaturated groundwater flow model. On the basis of a first‐order kinetic model for removal, we predicted diel fluctuations in stream concentrations. Model results indicated that ET drove a diel pattern in specific discharge through the streambed and riparian zone (the removal zones). Because specific discharge is inversely proportional to groundwater travel time through the removal zones and travel time determines the extent of removal, diel changes in ET can result in a diel pattern in concentration in the stream. The model predictions generally matched observations made during summertime base‐flow conditions in a small coastal plain stream in Virginia. A more complicated pattern was observed following a seasonal drawdown period, where source components to the stream changed during the receding limb of the hydrograph and resulted in diel fluctuations being superimposed over a multi‐day trend in concentrations. Copyright © 2013 John Wiley & Sons, Ltd.
Fabrication of AC@ZSM‐5 core‐shell particles and their performance in Fischer–Tropsch synthesis
Authors: Chen Fengqiu , Jin Weiyang , Cheng Dang‐guo , Zhan Xiaoli , Lin Y.S.
Published: March 2013

Background

Because of its rough surface and the hydrophobic property of porous activated carbon (AC) particles, it is more difficult to grow a zeolite layer on an AC surface than on metal oxides. The aim of the present study is the in situ hydrothermal synthesis of continuous ZSM‐5 zeolite layer encapsulated porous AC particles (AC@ZSM‐5) through an alumina intermediate layer strategy. To evaluate the effects of the zeolite layer on its catalytic application, active species (Co and Zr) were introduced into the AC and used for Fischer–Tropsch synthesis.

Results

A continuous zeolite layer cannot be formed on the surface of the irregular AC particles, even when pretreated by air oxidation or concentrated nitric acid, but can be synthesized using the alumina intermediate layer method. A catalytic test of CoZr/AC@ZSM‐5 indicates that the zeolite layer shell has a marked effect on product distributions.

Conclusion

Aided by the alumina intermediate layer, zeolite crystals nucleate at the support/solution interface rather than in solution. For Fischer–Tropsch synthesis over CoZr/AC@ZSM‐5, the product distributions are shifted to methane and light hydrocarbon compared with that of CoZr/AC. © 2013 Society of Chemical Industry
Entrepreneurial Thinking and Your Resolve
Authors: Taulbert Clifton L.
Published: March 2013

Taulbert finds that since the financial crisis of 2008, workplaces are faced with financial pressures and restraints, increased competitiveness, and “in some cases a lack of employee commitment and accountability.” Yet bottom‐line success still must be achieved, and how the leader articulates the vision and mission continues to matter. Leaders must embrace and model entrepreneurial thinking, and the “growth mind‐set” articulated by Stanford University's Dr. Carol Dweck. With this way of thinking, one's abilities are capable of continued growth and learning, not fixed and unchangeable. This mind‐set represents, he writes, “the path of opportunity and success.”
Enhanced Fluorescent Assignment of Protein Aggregates by an Oligothiophene–Porphyrin‐Based Amyloid Ligand
Authors: Arja Katriann , Sjölander Daniel , Åslund Alma , Prokop Stefan , Heppner Frank L. , Konradsson Peter , Lindgren Mikael , Hammarström Per , Åslund K. O. Andreas , Nilsson K. Peter R.
Published: March 2013

Fluorescent probes identifying protein aggregates are of great interest, as deposition of aggregated proteins is associated with many devastating diseases. Here, we report that a fluorescent amyloid ligand composed of two distinct molecular moieties, an amyloidophilic pentameric oligothiophene and a porphyrin, can be utilized for spectral and lifetime imaging assessment of recombinant Aβ 1‐42 amyloid fibrils and Aβ deposits in brain tissue sections from a transgenic mouse model with Alzheimer's disease pathology. The enhanced spectral range and distinct lifetime diversity of this novel oligothiophene–porphyrin‐based ligand allow a more precise assessment of heterogeneous amyloid morphology compared with the corresponding oligothiophene dye.

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Performance and aviation applications of minisodars at Hong Kong International Airport
Authors: Chan P. W.
Published: March 2013

The performance and aviation application of minisodars at Hong Kong International Airport are discussed in this paper. There are two minisodars at the airport and they have been in use for more than 2 years. The data availability at various measurement heights shows that the minisodars in general provide reasonably good coverage for aviation applications. The minisodar's wind data compare well with other measurements, including the anemometer data and LIDAR (light detection and ranging) data. The applications of minisodar data are then described. They are found to provide useful indications of low‐level windshear, mechanical turbulence associated with complex terrain, and downburst associated with a thunderstorm. Through these case studies, the minisodars are found to provide good supplementary data to other remote sensing meteorological instruments, such as LIDAR and radar, in the monitoring of low‐level wind changes that may be encountered by the aircraft.
Hypocholesterolemic effect of capsaicinoids by increased bile acids excretion in ovariectomized rats
Authors: Zhang Lei , Zhou Min , Fang Guoshan , Tang Yan , Chen Zongdao , Liu Xiong
Published: March 2013

Scope

This study investigated the interaction of dietary capsaicinoids with the mRNA and protein expressions of key receptors and enzymes involved in cholesterol metabolism in ovariectomized (OVX) rats.

Methods and results

Female Sprague‐Dawley rats were subjected to sham operation or ovariectomy. The sham group and OVX control group were fed with high‐cholesterol diets, whereas the treatment group (control diet containing 0.01% capsaicinoids) was fed with high‐cholesterol plus 0.01% capsaicinoids diet for 21 days. Capsaicinoids significantly decreased the body weight gain, plasma total cholesterol, LDL cholesterol, and triacylglycerol without affecting the high‐density lipoprotein cholesterol in the OVX rats. The change in plasma lipoprotein profile was accompanied by a greater excretion of total bile acid in feces and small intestinal contents. Western blot and real‐time PCR analyses revealed that capsaicinoids significantly enhanced the expressions of hepatic cholesterol 7α‐hydroxylase and transient receptor potential vanilloid type‐1 but did not affect the expression of 3‐hydroxy‐3‐methylglutaryl‐CoA reductase in the OVX rats.

Conclusion

Capsaicinoids have cholesterol‐lowering effects in OVX rats. The hypocholesterolemic activity of capsaicinoids is caused by the stimulating conversion of cholesterol to bile acids by upregulation of cholesterol 7α‐hydroxylase expression and the increase in fecal total bile acid excretion.
Hierarchical crystalline structures and dynamic mechanical properties of injection‐molded bars of HDPE: attributes of temperature field
Authors: Wang Long , Yang Ming‐Bo , Zhang Quan‐Ping , Zhang Rui‐Yan , Wu Jing‐Jing , Feng Jian‐Ming
Published: March 2013

The relationship among the processing parameters, crystalline morphologies and mechanical properties of injected‐molded bar becomes much complicated primarily due to the existence of temperature gradient coupled with the shear gradient along the sample thickness. The effect of thermal gradient field on the microstructural evolution, hierarchical structures and dynamic mechanical properties of high‐density polyethylene parts molded via gas‐assisted injection molding (GAIM) were investigated using scanning electron microscope, differential scanning calorimetry, dynamic mechanical analysis and two‐dimensional wide‐angle X‐ray diffraction. The three‐dimensional temperature profiles during the cooling stage under different melt temperatures of GAIM process were obtained by using a transient heat transfer model of the enthalpy transformation approach, and the phase‐change plateaus were clearly observed in the cooling curves. It was found that a variety of melt temperatures could induce considerable variations of the hierarchical structures, orientation behavior and dynamic mechanical properties of the injection‐molded bars. With reduced melt temperature, GAIM samples with higher molecular orientation and improved dynamic mechanical properties were obtained. Copyright © 2013 John Wiley & Sons, Ltd.
Acute Myocardial Infarction During Regadenoson Myocardial Perfusion Imaging
Authors: Shah Sachil , Parra David , Rosenstein Robert S.
Published: March 2013

Pharmacologic stress testing uses vasodilators to provide objective evidence of myocardial ischemia. Adenosine and dipyridamole are nonselective adenosine receptor agonists that have been associated with myocardial infarction (MI) during intravenous infusion. Mechanisms postulated for this effect include coronary steal, transmural steal, global hypotension, and direct vasoconstriction. Regadenoson, a direct A2A agonist, was approved for use in stress testing in 2008. We describe a 68‐year‐old man who presented to our institution with typical angina, relieved by nitroglycerin. He did not have electrocardiogram (ECG) changes suggestive of myocardial pathology, and laboratory testing did not reveal a significant rise in troponin‐I levels. To further assess the etiology of his symptoms, he underwent a pharmacologic stress test with regadenoson followed by technetium 99 m sestamibi. Six minutes after regadenoson infusion, the patient developed severe retrosternal chest pain accompanied by ST elevations on ECG. Sublingual nitroglycerin was administered that resolved both the pain and ECG changes. The patient subsequently underwent urgent coronary angiography and was found to have a 95% critical stenosis involving the left anterior descending artery. We conclude this case represents a MI secondary to coronary steal phenomenon induced by regadenoson infusion. Clinicians should be aware this adverse effect can occur despite the improved side‐effect profile of regadenoson. Continuous monitoring of vital signs and the ECG with regular assessment of symptoms is imperative to identify this rare but potentially devastating adverse event.
Rapid radiative platinisation for dye‐sensitised solar cell counter electrodes
Authors: Charbonneau Cecile , Hooper Katherine , Carnie Matthew , Searle Justin , Philip Bruce , Wragg David , Watson Trystan , Worsley David
Published: March 2013

The successful transition of dye‐sensitised solar cell (DSC) manufacture from laboratory to factory requires new thinking in terms of lowering cost and removing time consuming manufacturing process. Platinisation of the fluorine doped tin oxide (FTO) glass counter electrode is essential for the operation of a conventional DSC and is usually carried out by thermal decomposition of chloroplatinic acid at 385 °C for 30 min. Here, near infrared radiation is used to directly heat the FTO layer resulting in full platinisation in 12.5 s. These platinised electrodes behave identically to those produced via conventional static thermal treatment in assembled DSC devices. Copyright © 2013 John Wiley & Sons, Ltd.
HEIGHTENED TEST ANXIETY AMONG YOUNG CHILDREN: ELEMENTARY SCHOOL STUDENTS’ ANXIOUS RESPONSES TO HIGH‐STAKES TESTING
Authors: Segool Natasha K. , Carlson John S. , Goforth Anisa N. , von der Embse Nathan , Barterian Justin A.
Published: March 2013

This study explored differences in test anxiety on high‐stakes standardized achievement testing and low‐stakes testing among elementary school children. This is the first study to directly examine differences in young students’ reported test anxiety between No Child Left Behind (NCLB) achievement testing and classroom testing. Three hundred thirty‐five students in Grades 3 through 5 participated in the study. Students completed assessments of test anxiety following NCLB testing and typical classroom testing. Students reported significantly more overall test anxiety in relation to high‐stakes testing versus classroom testing on two measures of test anxiety, effect sizes r = −.21 and r = −.10. Students also reported significantly more cognitive (r = −.20) and physiological (r = −.24) symptoms of test anxiety in relation to high‐stakes testing. This study adds to the test anxiety literature by demonstrating that students experience heightened anxiety in response to NCLB testing.
Mutual coupling of antennas in a meteor radar interferometer
Authors: Younger J.P. , Reid I.M. , Vincent R.A.
Published: March 2013

Meteor radars have become common and important tools in the study of the climate and dynamics of the mesosphere/lower thermosphere (MLT) region. These systems depend on accurate angle‐of‐arrival measurements to locate the positions of meteor trails in the atmosphere. Mutual coupling between antennas, although small, produces a measurable error in the antenna pair phase differences used to deduce the angle of arrival of incident radiation. Measurements of the scattering parameter matrix for antennas in an interferometric meteor radar array have been made and applied to the existing angle‐of‐arrival calculation algorithm. The results indicate that mutual coupling of antennas in the array produces errors in the zenith angle estimate of less than ± 0.5°. This error is primarily in the form of a gradient across the field of view of the radar, which can be removed using existing phase calibration methods. The remaining error is small but will produce small systematic variations in the height estimates for detected meteors.
The Role of Surface Chemistry on the Toxicity of Ag Nanoparticles
Authors: Xiong Yujie , Brunson Mark , Huh Juyoung , Huang Aaron , Coster Adam , Wendt Kristy , Fay Justin , Qin Dong
Published: March 2013

The role of surface chemistry on the toxicity of Ag nanoparticles is investigated using Saccharomyces cerevisiae yeast as a platform for evaluation. Combining the shape‐controlled synthesis of Ag nanoparticles with a comprehensive characterization of their physicochemical properties, an understanding is formed of the correlation between the physicochemical parameters of nanoparticles and the inhibition growth of yeast cells upon the introduction of nanoparticles into the cell culture system. Capping agents, surface facets, and sample stability—the three experimental parameters that are inherent from the wet‐chemical synthesis of Ag nanoparticles—have a strong impact on toxicity evaluation. Hence, it is important to characterize surface properties of Ag nanoparticles in the nature of biological media and to understand the role that surface chemistry may interplay to correlate the physicochemical properties of nanoparticles with their biological response upon exposure. This work demonstrates the great importance of surface chemistry in designing experiments for reliable toxicity evaluation and in mitigating the toxicity of Ag nanoparticles for their safe use in future commercialization.
Recent Developments in Samarium Diiodide Promoted Organic Reactions
Authors: Gopalaiah Kovuru , Kagan Henri B.
Published: March 2013

In the early eighties, we introduced samarium diiodide for the transformation of various functional groups. Since then, this reducing agent has been extensively used for the reductive cleavage of single bonds, C‐C bond formations, C‐N bond formations, and β‐elimination reactions. In this Personal Account, we highlight our initial results, as well as some of the contributions from various research groups. Because of space limitations, we arbitrarily select some useful results that have recently been described in literature.
Numerical investigation of airflow through a Savonius rotor
Authors: Jaohindy P. , Ennamiri H. , Garde F. , Bastide A.
Published: March 2013

The aim of this report is to present a model of a rigid‐rotor system based on computational fluid dynamics (CFD), which is applied on a vertical axis wind turbine (VAWT) research. Its originality results from the use of the average value of the variable rotational speed method taken in a periodic steady‐state (PSS) of the VAWT rotor instead of the classical fixed rotational speed method. This approach was chosen in order to determine the mechanical and aerodynamic parameters of the wind turbine. The modeling method uses an implicit Euler iterative solution strategy, which resolves the coupling between fixed and moving rotor domains. The main methods that were adopted are based on the three‐dimensional modeling of the interaction of the fluid flow with a rigid‐rotor. The strategy consists of using the Reynolds averaged Navier Stokes (RANS) equations with the standard k‐ ϵ and SST k‐ ω models to solve the fluid flow problem. To perform the rigid‐rotor motion in a fluid, the one degree of freedom (1‐DOF) method was applied. In the present study, the steady‐state and dynamic CFD simulations of the Savonius rotor are adopted to contribute to the validation elements of the VAWT models that are used. The dynamic study allows the investigation of the rotor behavior and the relation between velocity, pressure, and vorticity fields in and around the rotor blades. The flow fields generated by the rotation of the Savonius rotor were investigated in the half revolution period of the rotor angle θ from 0° to 180°. In this range of θ, the focus is on generating and dissipating vortices. Copyright © 2013 John Wiley & Sons, Ltd.
Root size and soil environments determine root lifespan: evidence from an alpine meadow on the Tibetan Plateau
Authors: Wu Yibo , Deng Yongcui , Zhang Jing , Wu Jing , Tang Yanhong , Cao Guangmin , Zhang Fawei , Cui Xiaoyong
Published: March 2013

We used a minirhizotron system to investigate the influence of three major factors—root morphology, root depth, and season of root emergence—on root survivorship and longevity in aKobresia humilismeadow on the Tibetan Plateau during the growing season of 2009. Root longevity was assessed by survival analysis, Kaplan–Meier analysis, and Cox proportional hazards regression. Root longevity was correlated positively with root diameter. A 17.5 % decrease in the risk of mortality was associated with a 0.1‐mm increase in diameter. Roots distributed in the top 10 cm of the soil had significantly shorter longevities than roots at greater depths, with a 48 % decrease of mortality risk for each 10‐cm increase in soil depth from the surface to 40 cm. Of all the factors examined, the season of root emergence had the strongest effect on root lifespan. Roots that emerged in May and June had shorter longevity than roots that emerged later in the year, and roots that emerged in September and October were more likely to survive over winter. Our findings indicated that life‐history traits of roots inK. humilismeadows are highly heterogeneous, and this heterogeneity should be considered when modeling the contribution of roots to carbon and nitrogen fluxes in this type of meadow ecosystem. Moreover, temporal, spatial, and compositional variations in root longevity must be considered.
Modeling fMRI Data: Challenges and Opportunities
Authors: Maydeu-Olivares Alberto , Brown Gregory
Published: March 2013

We offer an introduction to the five papers that make up this special section. These papers deal with a range of the methodological challenges that face researchers analyzing fMRI data—the spatial, multilevel, and longitudinal nature of the data, the sources of noise, and so on. The papers all provide analyses of data collected by a multi-site consortium, the Function Biomedical Informatics Research Network. Due to the sheer volume of data, univariate procedures are often applied, which leads to a multiple comparisons problem (since the data are necessarily multivariate). The papers in this section include interesting applications, such as a state-space model applied to these data, and conclude with a reflection on basic measurement problems in fMRI. All in all, they provide a good overview of the challenges that fMRI data present to the standard psychometric toolbox, but also to the opportunities they offer for new psychometric modeling.
The effect of amyloid β on cognitive decline is modulated by neural integrity in cognitively normal elderly
Authors: Wirth Miranka , Oh Hwamee , Mormino Elizabeth C. , Markley Candace , Landau Susan M. , Jagust William J.
Published: March 2013

Objective

Alzheimer's disease (AD) pathology of amyloid β (Aβ) accumulation and neurodegeneration may be relevant to preclinical cognitive decline. The objective of this study was to relate AD‐sensitive biomarkers of Aβ and neurodegeneration and their interaction to longitudinal cognitive change in cognitively normal elderly.

Methods

Thirty‐eight older people completed at least three consecutive neuropsychological examinations. Using positron emission tomography (PET), Aβ plaque burden was measured with [11C]Pittsburgh compound B (PiB). PiB retention was dichotomized into a positive (n = 13) and negative (n = 25) PiB status. Neurodegenerative biomarkers were extracted within AD‐vulnerable regions of interest (ROIs)—namely, the hippocampus and temporoparietal cortical areas. Within each ROI, metabolism was quantified with [18F] fluorodeoxyglucose (FDG) PET, and the gray matter structure was evaluated using volume (hippocampus) or thickness (cortical regions). ROI‐specific functional and structural biomarkers were combined further into cross‐modality neurodegenerative composite measures. Using hierarchical regression models, PiB and the neurodegenerative biomarkers were related to cognitive trajectories.

Results

PiB positivity was associated with memory and nonmemory worsening. The neurodegenerative biomarkers modified these relationships. Longitudinal cognitive decline was accelerated in those individuals who exhibited both PiB positivity and lower neurodegenerative biomarker scores, although the two measures appeared to be independent. PiB retention interacted predominantly with the cortical neurodegenerative composite for nonmemory change. Memory decline was best explained by the interaction between PiB and the hippocampal neurodegenerative composite, suggesting regional specificity of the neurodegenerative modulations.

Conclusions

Our findings indicate that cognitive trajectories deteriorate at a faster rate in cognitively normal individuals expressing Aβ burden and neurodegeneration within specific AD‐sensitive regions.
ON THE -LENGTH AND THE WIELANDT LENGTH OF A FINITE -SOLUBLE GROUP
Authors: SU NING , WANG YANMING
Published: March 2013

The $p$-length of a finite $p$-soluble group is an important invariant parameter. The well-known Hall–Higman $p$-length theorem states that the $p$-length of a $p$-soluble group is bounded above by the nilpotent class of its Sylow $p$-subgroups. In this paper, we improve this result by giving a better estimation on the $p$-length of a $p$-soluble group in terms of other invariant parameters of its Sylow $p$-subgroups.