bluuebunny/crossref_metadata_2025 huggingface dataset:
Convergent mechanisms in pluripotent stem cells and cancer: Implications for stem cell engineering
Authors: Mooney Bridget M. , Raof Nurazhani Abdul , Li Yan , Xie Yubing
Published: February 2013

Stem cells and cancer cells share certain characteristics, including the capacity to self‐renew, differentiatie, and undergo epithelial‐to‐mesenchymal transition (EMT). The mechanisms underlying tumorigenesis retain similarities with processes in normal stem cell development. Comprehensive analysis and comparison of cancer cell and stem cell development will advance the study of cancer progression, enabling development of effective strategies for cancer treatment. In this review article, we first examine the convergence of outcome, cellular communication, and signaling pathways active in pluripotent stem cells and cancer cells. Next, we detail how stem cell engineering is able to mimic in vivo microenvironments. These efforts can help better identify stem cell‐cancer cell interactions, elucidated dysregulated pluripotent signaling pathways occurring in cancer, revealed new factors that restrict tumorigenesis and metastasis potential, and reprogrammed cancer cells to a less aggressive phenotype. The potential of stem cell engineering to enhance cancer research is tremendous and may lead to alternative therapeutic options for aggressive cancers.
Lipophilic Extracts from Needles and Defoliated Twigs of Pinus pumila from Two Different Populations
Authors: Shpatov Alexander V. , Popov Sergey A. , Salnikova Olga I. , Shmidt Emma N. , Kang Suk Woo , Kim Sang Min , Um Byung Hun
Published: February 2013

Hexane extracts of needles and defoliated twigs of Pinus pumila (Pall.) Regel from two distant populations, located in the southwest and the east (i.e., Lake Baikal region and Sakhalin Island) of the species distribution range were studied by GC/MS analysis. Composition and retention indices of major components were determined. A drastic composition divergence for the extracts of P. pumila needles and defoliated twigs, depending on growth location, was established. Needle extracts from the eastern population sample contained mainly labdane‐type acids (anticopalic acid derivatives), whereas the predominant components of needle extracts from the other population sample were abietane‐type acids (abietic, neoabietic acids) and isopimarane‐type diterpenoids (sandaracopimaric acid, sandaracopimaradien‐3β‐ol). The main components of defoliated twig extracts from Sakhalin Island population sample were abietane‐type acids and cembrane‐type diterpenoids, while content of these compounds in the extracts of the southwestern marginal population sample was remarkably lower.
Molecular Spoked Wheels: Synthesis and Self‐Assembly Studies on Rigid Nanoscale 2D Objects
Authors: Aggarwal A. Vikas , Jester Stefan‐S. , Taheri Sara Mehdizadeh , Förster Stephan , Höger Sigurd
Published: February 2013

We present the efficient synthesis of a new molecular spoked‐wheel structure (MSW‐3). Two derivatives with diameters of approximately 4 nm have been prepared. By highlighting the importance of pseudo‐high‐dilution conditions during cyclization, we were able to access the compounds on a several hundred milligram scale. In addition to the standard characterization (NMR spectroscopy, MS), we describe a detailed investigation of the optical properties of the fluorescent MSWs by comparison with appropriate model chromophores. Furthermore, a comprehensive study of the structure in solution by means of light‐ and X‐ray scattering experiments has been conducted. Scanning tunneling microscopy (STM) revealed the two‐dimensional organization of the molecules on highly oriented pyrolytic graphite and emphasized the spoked‐wheel structure. The diameter of these molecules measured by small‐angle X‐ray scattering is in very good agreement with that obtained from STM and matches the results of molecular modeling. This confirms the rigidifying effect of the spokes, which results in highly shape‐persistent nanometer‐sized oblate organic compounds.
Escherichia coli β‐Galactosidase Inhibitors through Modifications at the Aglyconic Moiety: Experimental Evidence of Conformational Distortion in the Molecular Recognition Process
Authors: Calle Luis , Roldós Virginia , Cañada F. Javier , Uhrig María Laura , Cagnoni Alejandro J. , Manzano Verónica E. , Varela Oscar , Jiménez‐Barbero Jesus
Published: February 2013

Herein, we describe the use of thioglycosides as glycosidase inhibitors by employing novel modifications at the reducing end of these glycomimetics. The inhibitors display a basic galactopyranosyl unit (1→4)‐bonded to a 3‐deoxy‐4‐thiopentopyranose moiety. The molecular basis of the observed inhibition has been studied by using a combination of NMR spectroscopy and molecular modeling techniques. It is demonstrated that these molecules are not recognized by Escherichia coli β‐galactosidase in their ground‐state conformation, with a conformational selection process taking place. In fact, the observed conformational distortion depends on the chemical nature of the compounds and results from the rotation around the glycosidic linkage (variation of Φ or Ψ) or from the deformation of the six‐membered ring of the pentopyranose. The bound conformations of the ligand are adapted in the enzymatic pocket with a variety of hydrogen‐bond, van der Waals, and stacking interactions.
A Total Synthesis of Spirastrellolide A Methyl Ester
Authors: Arlt Alexander , Benson Stefan , Schulthoff Saskia , Gabor Barbara , Fürstner Alois
Published: February 2013

A concise total synthesis of spirastrellolide A methyl ester (1 a, R1=Me) as the parent compound of a series of highly cytotoxic marine macrolides is disclosed, which exploits and expands the flexibility of a synthesis plan previously developed by our group en route to the sister compound spirastrellolide F methyl ester (6 a, R1=Me). Key to success was the masking of the signature Δ15,16‐bond of 1 a as a C16‐carbonyl group until after the stereogenic center at C24 had been properly set by a highly selective hydrogenation of the C24 exo‐methylene precursor 66. Conformational control over the macrocyclic frame allowed the proper stereochemical course to be dialed into this reduction process. The elaboration of the C16 ketone to the C15–C16 double bond was accomplished by a chemoselective alkenyl triflate formation followed by a palladium‐catalyzed hydride delivery. The role of the ketone at C16 as a strategic design element is also evident up‐stream of the key intermediate 66, the assembly of which hinged upon the addition of the polyfunctionalized dithiane 37 to the similarly elaborate aldehyde fragment 46. Other crucial steps of the total synthesis were an alkyl‐Suzuki coupling and a Yamaguchi lactonization that allowed the Northern and the Southern sector of the target to be stitched together and the macrocyclic perimeter to be forged. The lateral chain comprising the remote C46 stereocenter was finally attached to the core region by a modified Julia–Kocienski olefination. The preparation of the individual building blocks led to some methodological spin‐offs, amongst which the improved procedure for the N–O‐bond cleavage of isoxazolines by zero‐valent molybdenum and the ozonolysis of a double bond in the presence of other oxidation‐prone functionality are most noteworthy. Preliminary biological data suggest that the entire carbon framework, that is the macrocyclic core plus the lateral chain, might be necessary for high cytotoxicity.
Hierarchical Structures Based on Functionalized Magnetic Cores and Layered Double‐Hydroxide Shells: Concept, Controlled Synthesis, and Applications
Authors: Shao Mingfei , Wei Min , Evans David G. , Duan Xue
Published: February 2013

The combination of magnetic particles and layered double hydroxide (LDHs) materials leads to the formation of hierarchical composites that can take full advantages of each component; this is an effective approach for achieving multifunctional materials with intriguing properties. This Concept article summarizes several important strategies for the fabrication of magnetic‐core/LDH‐shell hierarchical nanocomposites, including direct coprecipitation, layer‐by‐layer assembly, and in situ growth methods. The obtained nanocomposites exhibit excellent performance as multifunctional materials for promising applications in targeted drug delivery, efficient separation, and catalysis. The fabrication and application of magnetic‐core/LDH‐shell nanocomposite materials represent a new direction in the development of LDH‐based multifunctional materials, which will contribute to the progress of chemistry and material science.
Reaction Engineering Investigations of the Partial Oxidation of o‐Xylene in the Explosion Regime – Microfixed Bed versus Catalyst Coating
Authors: Lange Thomas , Heinrich Sebastian , Liebner Christian , Hieronymus Hartmut , Klemm Elias
Published: February 2013

The selective gas phase oxidation of o‐xylene was investigated inside of the explosion regime using a microstructured reactor. The V2O5/TiO2 catalyst was used as microfixed bed and as catalyst coating. There were no significant losses of the selectivity to phthalic anhydride with feed compositions up to 7 vol % o‐xylene observable. Above 7 vol % the selectivity decreased due to total oxidation, especially for the microfixed bed, which was probably caused by a hotspot.
Nuclear Flux Densities during a Model Pericyclic Reaction with Energies Well Above and Below the Potential Barrier
Authors: Bredtmann Timm , Kono Hirohiko , Manz Jörn , Nakamura Kosuke , Stemmle Christian
Published: February 2013

Pericyclic reactions with energies E well above the potential energy barrier B (case E>B) proceed with quantum nuclear flux densities 〈j〉 which are essentially proportional to the nuclear densities ρ in the femtosecond time domain. This corresponds to the definition of classical (cl) mechanics, jcl=υclρcl, with almost constant velocity vcl. For the other case E<B, however, that is, in the domain of coherent tunneling, we discover the opposite trend, that is, 〈j〉 has maximum value close to the barrier where ρ is a minimum (in fact where ρ is close to zero). The general conclusion is that quantum mechanical nuclear flux densities may be at variance from traditional expectations based on classical trajectories. This prediction calls for experimental demonstration. The counter‐intuitive proof‐of‐principle is demonstrated for a simple, one‐dimensional model of the Cope rearrangement of semibullvalene.
Crossing Over into the Future
Authors: Vashi Preeti
Published: February 2013

EurJIC is proud to present a bumper issue on Spin‐Crossover Complexes. Our Guest Editors, Keith Murray, Hiroki Oshio and José Antonio Real, have worked hard to put together a fantastic issue. With a valuable personal account of the field by Philipp Gütlich and inspiring papers by leading experts, you will not be disappointed.
Comparative study of olive oil quality from Chemlali Sfax versus Arbequina cultivated in Tunisia
Authors: Chtourou Mohamed , Gargouri Boutheina , Jaber Hazem , Abdelhedi Ridha , Bouaziz Mohamed
Published: February 2013

The effects of the geographical region on the behavior of the Arbequina olive cultivar (cv) cultivated in the south of Tunisia (in the arid zone of Sfax) was compared to an autochthonous cultivar (Chemlali Sfax). Various olive parameters were analyzed, such as ripening index, pulp/stone ratio, oil contents, and sensory profiles. Most of the quality indices and fatty acid composition showed significant variations among olive cultivars. Arbequina cv is characterized by high oil yield with a less total phenols and pigments content than Chemlali Sfax cv. Cielab spectrophotometer coordinate L*, b*, and a* values show a great difference in olive oil colors. In spite of their low oleic acid contents, autochthonous cultivar presented a higher induction time (6.82 and 2.68 h for Chemlali and Arbequina, respectively) and high contents of phenolic compounds (158.28 and 110.27 mg/kg for Chemlali Sfax and Arbequina, respectively). The most important compounds identified were oleuropein aglycon (45.50 mg/kg), hydroxytyrosol (3.68 mg/kg), 1‐acetoxypinoresinol (6.23 mg/kg) in Chemlali Sfax oil and hydroxytyrosol glucoside (25.15 mg/kg), tyrosol (12.51 mg/kg), and oleuropein aglycon (30.60 mg/kg) in Arbequina oil. Chemlali Sfax also possessed a very bitter taste, whereas the Arbequina had a sweet taste amongst its attributes. The principal component analysis of the results indicated that the geographical region has significantly affected the olive oil quality.
Stereoselective Synthesis of α‐Glycosyl Azides by TMSOTf‐Mediated Ring Opening of 1,6‐Anhydro Sugars
Authors: Lepage Mathieu L. , Bodlenner Anne , Compain Philippe
Published: February 2013

Access to α‐glycosyl azides in modest to high diastereoselectivity by way of TMSN3 ring‐opening of 1,6‐anhydro sugars mediated by TMSOTf is reported. The reaction tolerates a wide variety of functional groups including alcohol, alkyne, azide and ester groups. The efficient synthesis of a pseudopentasaccharide in five steps from commercially available levoglucosan by way of a “click‐click” approach is presented to highlight the interest of the TMSN3 ring‐opening reaction.
1,5,7‐Triazabicyclo[4.4.0]dec‐1‐ene‐Mediated Acetylene Dicarboxylation and Alkyne Carboxylation Using Carbon Dioxide
Authors: Wang Xi , Lim Yu Na , Lee Chan , Jang Hye‐Young , Lee Bun Yeoul
Published: February 2013

Direct carboxylation of acetylene with CO2was carried out in the presence of 1,5,7‐triazabicyclo[4.4.0]dec‐1‐ene (TBD); subsequent reduction of dicarboxylated acetylene produces commercially valuable succinate salts. This metal‐free carboxylation has potential economic and environmental impact by utilizing non‐petroleum feedstocks (acetylene) and CO2and by producing valuable chemical feed stocks.
Environmental toxicity and radioactivity assessment of a titanium-processing residue with potential for environmental use
Authors: Wendling Laura A. , Binet Monique T. , Yuan Zheng , Gissi Francesca , Koppel Darren J. , Adams Merrin S.
Published: February 2013

Thorough examination of the physicochemical characteristics of a Ti-processing residue was undertaken, including mineralogical, geochemical, and radiochemical characterization, and an investigation of the environmental toxicity of soft-water leachate generated from the residue. Concentrations of most metals measured in the leachate were low; thus, the residue is unlikely to leach high levels of potentially toxic elements on exposure to low–ionic strength natural waters. Relative to stringent ecosystem health-based guidelines, only chromium concentrations in the leachate exceeded guideline concentrations for 95% species protection; however, sulfate was present at concentrations known to cause toxicity. It is likely that the high concentration of calcium and extreme water hardness of the leachate reduced the bioavailability of some elements. Geochemical modeling of the leachate indicated that calcium and sulfate concentrations were largely controlled by gypsum mineral dissolution. The leachate was not toxic to the microalga Chlorella sp., the cladoceran Ceriodaphnia dubia, or the estuarine bacterium Vibrio fischeri. The Ti-processing residue exhibited an absorbed dose rate of 186 nGy/h, equivalent to an annual dose of 1.63 mGy and an annual effective dose of 0.326 mGy. In summary, the results indicate that the Ti-processing residue examined is suitable for productive use as an environmental amendment following 10 to 100 times dilution to ameliorate potential toxic effects due to chromium or sulfate. Environ Toxicol Chem 2013;32:1443–1452. © 2013 SETAC
Coextracted dissolved organic carbon has a suppressive effect on the acetylcholinesterase inhibition assay
Authors: Neale Peta A. , Escher Beate I.
Published: February 2013

The acetylcholinesterase (AChE) inhibition assay is frequently applied to detect organophosphates and carbamate pesticides in different water types, including dissolved organic carbon (DOC)–rich wastewater and surface water. The aim of the present study was to quantify the effect of coextracted DOC from different water samples on the commonly used enzyme-based AChE inhibition assay. Approximately 40% to 70% of DOC is typically recovered by solid-phase extraction, and this comprises not only organic micropollutants but also natural organic matter. The inhibition of the water extracts in the assay differed greatly from the expected mixture effects based on chemical analysis of organophosphates and carbamates. Binary mixture experiments with the known AChE inhibitor parathion and the water extracts showed reduced toxicity in comparison with predictions using the mixture models of concentration addition and independent action. In addition, the extracts and reference organic matter had a suppressive effect on a constant concentration of parathion. The present study thus indicated that concentrations of DOC as low as 2 mg carbon/L can impair the AChE inhibition assay and, consequently, that only samples with a final DOC concentration of less than 2 mgC/L are suitable for this assay. To check for potential suppression in environmental samples, standard addition experiments using an AChE-inhibiting reference compound are recommended. Environ Toxicol Chem 2013;32:1526–1534. © 2013 SETAC
Cross‐Linking of Sulfonated Poly(ether ether ketone) by Thermal Treatment: How Does the Reaction Occur?
Authors: Maranesi B. , Hou H. , Polini R. , Sgreccia E. , Alberti G. , Narducci R. , Knauth P. , Di Vona M. L.
Published: February 2013

The cross‐link reaction between macromolecular chains of sulfonated poly(ether ether ketone) (SPEEK) by thermal treatment above 150 °C in presence of dimethylsulfoxide (DMSO) is investigated by various techniques, including elemental analysis, acid‐base titration, infrared spectroscopy, water uptake (WU) measurements, and thermogravimetry. The conditions of thermal treatment are analyzed. The cross‐linking reaction occurs in at least three more or less activated and deactivated positions with different activation energies, leading to different time dependencies of the cross‐link reaction. The role of residual solvent DMSO is studied particularly: the cross‐linking depends significantly on the amount of solvent in the membranes. Implications on WU and thermal stability are of particular importance for the development of high performance proton‐conducting membranes.
Seasonal variability in concentration, composition, age, and fluxes of particulate organic carbon exchanged between the floodplain and Amazon River
Authors: Moreira‐Turcq Patricia , Bonnet Marie‐Paule , Amorim Marcelo , Bernardes Marcelo , Lagane Christelle , Maurice Laurence , Perez Marcela , Seyler Patrick
Published: February 2013

The composition, sources, and age of particulate organic matter were determined in an Amazonian river‐floodplain system during rising, high, falling, and low water periods over 7 yr (1999–2006), and a mass balance for total organic carbon (dissolved and particulate) was estimated. The Curuai floodplain, composed of several temporally interconnected lakes, is permanently connected to the Amazon River via channels. Organic matter (OM) is imported to the floodplain from the Amazon River mainly during the rising water period and produced in the floodplain and exported to the river during high and falling water periods. No significant exchanges occurred during low water periods. The OM produced in the floodplain is characterized by low C/N ratios and by high chlorophyll a concentrations (Chl‐a). The δ13C signature has a seasonal trend, with more negative δ13C values during the high water period than other periods. Δ14C results indicate that the bulk OM present in floodplain lakes is predominantly post‐bomb (i.e., post‐1950). Particulate organic carbon (POC) and dissolved organic carbon (DOC) fluxes exported by the Curuai floodplain represent 1.3% and 0.1%, respectively, of the POC and DOC annual fluxes in the mainstem Amazon River at Óbidos but may reach up to 3.3% and 0.8% during falling water. Based on Δ14C, δ13C, Chl‐a, and elemental analysis of the particulate organic matter, we demonstrate that floodplain lakes have intense phytoplankton and macrophyte primary production, which is partly exported to the main river channel. Floodplains are thus a significant source of modern and labile organic carbon to the river mainstem, where it can be rapidly degraded and recycled back to the atmosphere.
Frequency of the Cholesteryl Ester Storage Disease Common Lipa E8sjm Mutation (C.894G>A) in Various Racial And Ethnic Groups
Authors: Scott Stuart A. , Liu Benny , Nazarenko Irina , Martis Suparna , Kozlitina Julia , Yang Yao , Ramirez Charina , Kasai Yumi , Hyatt Tommy , Peter Inga , Desnick Robert J.
Published: February 2013

Cholesteryl ester storage disease (CESD) and Wolman disease are autosomal recessive later-onset and severe infantile disorders, respectively, which result from the deficient activity of lysosomal acid lipase (LAL). LAL is encoded by LIPA (10q23.31) and the most common mutation associated with CESD is an exon 8 splice junction mutation (c.894G>A; E8SJM), which expresses only ˜3%-5% of normally spliced LAL. However, the frequency of c.894G>A is unknown in most populations. To estimate the prevalence of CESD in different populations, the frequencies of the c.894G>A mutation were determined in 10,000 LIPA alleles from healthy African-American, Asian, Caucasian, Hispanic, and Ashkenazi Jewish individuals from the greater New York metropolitan area and 6,578 LIPA alleles from African-American, Caucasian, and Hispanic subjects enrolled in the Dallas Heart Study. The combined c.894G>A allele frequencies from the two cohorts ranged from 0.0005 (Asian) to 0.0017 (Caucasian and Hispanic), which translated to carrier frequencies of 1 in 1,000 to ˜1 in 300, respectively. No African-American heterozygotes were detected. Additionally, by surveying the available literature, c.894G>A was estimated to account for 60% (95% confidence interval [CI]: 51%-69%) of reported mutations among multiethnic CESD patients. Using this estimate, the predicted prevalence of CESD in the Caucasian and Hispanic populations is ˜0.8 per 100,000 (˜1 in 130,000; 95% CI: ˜1 in 90,000 to 1 in 170,000). Conclusion: These data indicate that CESD may be underdiagnosed in the general Caucasian and Hispanic populations, which is important since clinical trials of enzyme replacement therapy for LAL deficiency are currently being developed. Moreover, future studies on CESD prevalence in African and Asian populations may require full-gene LIPA sequencing to determine heterozygote frequencies, since c.894G>A is not common in these racial groups. (HEPATOLOGY 2013;53:958–965)
The selective therapeutic apheresis procedures
Authors: Sanchez Amber P. , Cunard Robyn , Ward David M.
Published: February 2013

Selective apheresis procedures have been developed to target specific molecules, antibodies, or cellular elements in a variety of diseases. The advantage of the selective apheresis procedures over conventional therapeutic plasmapheresis is preservation of other essential plasma components such as albumin, immunoglobulins, and clotting factors. These procedures are more commonly employed in Europe and Japan, and few are available in the USA. Apheresis procedures discussed in this review include the various technologies available for low‐density lipoprotein (LDL) apheresis, double filtration plasmapheresis (DFPP), cryofiltration, immunoadsorption procedures, adsorption resins that process plasma, extracorporeal photopheresis, and leukocyte apheresis. J. Clin. Apheresis 28:20–29, 2013. © 2013 Wiley Periodicals, Inc.
Cut Costs Using Working Capital Management: Part III
Authors: Sagner James S.
Published: February 2013

The old rationale for local offices or branches was the need for direct contact with customers, prospects, and salespeople. But business now operates in a nearly real‐time environment and is not concerned with regional cultural differences, interpersonal contact, the transmittal or exchange of paper‐based documents, or geographic distances. As strategies change through advances in telecommunications, the computer, and the Internet, a local presence is not required for business transactions. A careful evaluation is necessary to understand existing procedures, ascertain the peculiarities of legacy systems, and determine which costs are avoidable. © 2013 Wiley Periodicals, Inc.
Corporate Social Responsibility Initiatives Across the Value Chain
Authors: Caplan Dennis , Dutta Saurav K. , Lawson Raef A.
Published: February 2013

Corporate social responsibility (CSR) is more than an altruistic ideal: It is increasingly considered a business imperative that should help drive organizational strategy. This article explores how companies manage their CSR efforts along their upstream and downstream value chains, documenting differences across industries and between U.S. and foreign organizations. © 2013 Wiley Periodicals, Inc.
A partition function‐based weighting scheme in force field parameter development using ab initio calculation results in global configurational space
Authors: Wu Yao , Dai Xiaodong , Huang Niu , Zhao Lifeng
Published: February 2013

In force field parameter development using ab initio potential energy surfaces (PES) as target data, an important but often neglected matter is the lack of a weighting scheme with optimal discrimination power to fit the target data. Here, we developed a novel partition function‐based weighting scheme, which not only fits the target potential energies exponentially like the general Boltzmann weighting method, but also reduces the effect of fitting errors leading to overfitting. The van der Waals (vdW) parameters of benzene and propane were reparameterized by using the new weighting scheme to fit the high‐level ab initio PESs probed by a water molecule in global configurational space. The molecular simulation results indicate that the newly derived parameters are capable of reproducing experimental properties in a broader range of temperatures, which supports the partition function‐based weighting scheme. Our simulation results also suggest that structural properties are more sensitive to vdW parameters than partial atomic charge parameters in these systems although the electrostatic interactions are still important in energetic properties. As no prerequisite conditions are required, the partition function‐based weighting method may be applied in developing any types of force field parameters. © 2013 Wiley Periodicals, Inc.
Systematic and efficient side chain optimization for molecular docking using a cheapest‐path procedure
Authors: Schumann Marcel , Armen Roger S.
Published: February 2013

Molecular docking of small‐molecules is an important procedure for computer‐aided drug design. Modeling receptor side chain flexibility is often important or even crucial, as it allows the receptor to adopt new conformations as induced by ligand binding. However, the accurate and efficient incorporation of receptor side chain flexibility has proven to be a challenge due to the huge computational complexity required to adequately address this problem. Here we describe a new docking approach with a very fast, graph‐based optimization algorithm for assignment of the near‐optimal set of residue rotamers. We extensively validate our approach using the 40 DUD target benchmarks commonly used to assess virtual screening performance and demonstrate a large improvement using the developed side chain optimization over rigid receptor docking (average ROC AUC of 0.693 vs. 0.623). Compared to numerous benchmarks, the overall performance is better than nearly all other commonly used procedures. Furthermore, we provide a detailed analysis of the level of receptor flexibility observed in docking results for different classes of residues and elucidate potential avenues for further improvement. © 2013 Wiley Periodicals, Inc.
HBV serum markers of 49164 patients and their relationships to HBV genotype in Fujian province of China
Authors: Lin Sheng , Liu Can , Shang Hongyan , Chen Huijuan , Yang Bin , Chen Jing , Chen Yong , Chen Dan , Ou Qishui
Published: February 2013

Background

There is a high prevalence of Hepatitis B virus (HBV) infection in China. The aim of this article is to reveal the HBV prevalence and its outcome in southern China by analyzing the HBV serum markers and their relationship to HBV genotype.

Methods

HBV serum markers, HBV–DNA and Alanine aminotransferase (ALT) of 49,164 patients were detected in Fujian Province of China, and HBV genotyping was conducted using melting curve method.

Results

23.46% patients (11,535/49,164) were found HBsAg‐positive and the concentration of ALT and HBV–DNA were positively correlated with HBsAg. The concentration of ALT and HBV–DNA markedly decreased when HBeAg turned negative or HBsAg concentration dropped to undetectable. The concentration of HBsAg and HBV–DNA were higher in genotype C than in genotype B and mixed genotype B/C, and the concentration of ALT in genotype C and B was higher than in mixed genotype B/C.

Conclusions

The positive rate of HBsAg of Fujian hospitalized patients is higher than in the previous reports. The concentration of HBsAg and HBV–DNA of genotype B is different from that of genotype C, and the concentration of HBsAg could be valuable in predicting the curative efficacy in HBV‐infected patients. J. Clin. Lab. Anal. 27:130–136, 2013. © 2013 Wiley Periodicals, Inc.
Glycerol etherification over acid ion exchange resins: effect of catalyst concentration and reusability
Authors: Pico María Pilar , Rosas Juana María , Rodríguez Sergio , Santos Aurora , Romero Arturo
Published: February 2013

Background

A study of the effect of different ion exchange resins, Amberlyst 15, Amberlite 200 and Amberlite IRC‐50, on glycerol etherification with tert‐butyl alcohol was performed. The best catalyst was selected based on the activity and selectivity values. The capability of reusing this catalyst after different pre‐treatments was analysed. A kinetic model was developed including the effect of catalyst concentration and temperature.

Results

Amberlyst 15 led to the highest glycerol conversion, the highest product yield, and it could be reused following proper pre‐treatment with methanol. The effect of catalyst concentration was evaluated and included in a previous kinetic model. Simulated results were found to be suitably fitted to the experimental ones.

Conclusions

The high activity value of Amberlyst 15 is related to its high acidity and better textural properties. Reuse of this catalyst was possible with an appropriate previous treatment. A kinetic model was validated including the effect of catalyst concentration and temperature on reactants conversion and products distribution. © 2013 Society of Chemical Industry
A Collective Effort to Understand Formalized Program Review
Authors: Sowcik Matthew , Lindsey Jill L. , Rosch David M.
Published: February 2013

In response to the growing field of Leadership Studies, the International Leadership Association appointed a task force to explore questions concerning formalized program review systems, such as a peer review process, accreditation, and/or certification. The inquiry involved questions regarding the value of a formalized program review process to advance the field of leadership studies and discover important patterns emerging in areas such as content, teaching, outcomes, and assessment. This article provides a summary of the work completed by the International Leadership Association's Formalized Program Review task force from 2011–2012 to explore and recommend options related to formalized program review for curricular based leadership studies programs.
Magnetic resonance elastography of liver: Technique, analysis, and clinical applications
Authors: Venkatesh Sudhakar K. , Yin Meng , Ehman Richard L.
Published: February 2013

Many pathological processes cause marked changes in the mechanical properties of tissue. MR elastography (MRE) is a noninvasive MRI based technique for quantitatively assessing the mechanical properties of tissues in vivo. MRE is performed by using a vibration source to generate low frequency mechanical waves in tissue, imaging the propagating waves using a phase contrast MRI technique, and then processing the wave information to generate quantitative images showing mechanical properties such as tissue stiffness. Since its first description in 1995, published studies have explored many potential clinical applications including brain, thyroid, lung, heart, breast, and skeletal muscle imaging. However, the best‐documented application to emerge has been the use of MRE to assess liver disease. Multiple studies have demonstrated that there is a strong correlation between MRE‐measured hepatic stiffness and the stage of fibrosis at histology. The emerging literature indicates that MRE can serve as a safer, less expensive, and potentially more accurate alternative to invasive liver biopsy which is currently the gold standard for diagnosis and staging of liver fibrosis. This review describes the basic principles, technique of performing a liver MRE, analysis and calculation of stiffness, clinical applications, limitations, and potential future applications. J. Magn. Reson. Imaging 2013;37:544–555. © 2012 Wiley Periodicals, Inc.
Is There a Developmental Slump in Creativity in China? The Relationship Between Organizational Climate and Creativity Development in Chinese Adolescents
Authors: Yi Xinfa , Hu Weiping , Plucker Jonathan A. , McWilliams Jenna
Published: February 2013

The major objectives of this study were to determine the characteristics of creativity development of Chinese children, the creative organizational climate of Chinese schools, and the relations among them. The results provided evidence that the creativity scores of children in elementary school were significantly higher than those of children in middle school. The teachers' evaluation of the creative organizational climate of the elementary school was significantly higher than that of the middle school. When the two variables were analyzed together, both the creative organizational climate of schools and the creative thinking development of children decreased during the children's development. Moreover, the creativity and climate scores were highly correlated, and the results from a path analysis suggested that a school's creative organizational climate has a significant impact on all seven dimensions of creativity measured in this study.
Creativity in the Later Life: Factors Associated with the Creativity of the Chinese Elderly
Authors: Zhang Wei , Niu Weihua
Published: February 2013

This study examined a total of 140 elderly Chinese from China and the United States to investigate the relationship between attitude toward aging, daily activities, general health, education, and other demographics and rated creativity as measured by collage making and storytelling. The result of this study shows that creativity declines with age. However, education, general health status, daily activities, and the attitude toward aging are also found to be decisive factors of creativity. The implications of the findings are discussed.
Early decrease of serum biomarkers of type II collagen degradation (Coll2‐1) and joint inflammation (Coll2‐1 NO2) by hyaluronic acid intra‐articular injections in patients with knee osteoarthritis: A research study part of the Biovisco study
Authors: Henrotin Y. , Chevalier X. , Deberg M. , Balblanc J.C. , Richette P. , Mulleman D. , Maillet B. , Rannou F. , Piroth C. , Mathieu P. , Conrozier T. ,   On behalf of the Osteoarthritis Group of the French Society of Rheumatology
Published: February 2013

To measure the evolution of the serum levels of specific Osteoarthritis (OA) biomarker, Coll2‐1 and Coll2‐1 NO2 in knee osteoarthritic patients after viscosupplementation (VS). Fifty‐one patients with unilateral symptomatic knee were recruited for this prospective open label study. They received three intra‐articular injections of 2 ml of hyaluronic acid (Hylan GF‐20) and were followed for 3 months. Walking pain was evaluated and serum samples were taken at each visit. Coll2‐1 and Coll2‐1 NO2 were measured in the serum using specific immunoassays. Variations over time of each parameter and predictive factor of response were studied. Forty‐five patients were analyzed. The serum concentrations of Coll2‐1 and Coll2‐1 NO2 were significantly higher in KL III/IV patients compared to KL I/II patients at baseline and decreased systematically over time after VS. Its effect was ever more pronounced in patients with KL III/IV. The serum concentration of Coll2‐1 was significantly lower at baseline in responders than in non‐responders. This study suggests a rapid slowdown of type II collagen degradation and joint inflammation after VS with Hylan G‐20 and gives additional information for the validation of accurate biomarkers for OA. The serum level of Coll2‐1 appeared to be a predictive factor for response to treatment. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 901–907, 2013
Numerical invariants of Fano 4‐folds
Authors: Casagrande Cinzia
Published: February 2013

Let X be a Fano 4‐fold. For any prime divisor D in X, consider \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal {N}_1(D,X):=i_*(\mathcal {N}_1(D))\subseteq \mathcal {N}_1(X)$\end{document} where i* is the push‐forward of one‐cycles, and let cD be the codimension of \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal {N}_1(D,X)$\end{document} in \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal {N}_1(X)$\end{document}. We define an integral invariant cX of X as the maximal cD, where D varies among all prime divisors in X. We know from 3 that if cX > 2, then either X is a product of Del Pezzo surfaces and ρX ≤ 18, or cX = 3 and ρX ≤ 6. In this paper we show that if cX = 2, then ρX ≤ 12.
Radiolabeled Nanogels for Nuclear Molecular Imaging
Authors: Singh Smriti , Bingöl Bahar , Morgenroth Agnieszka , Mottaghy Felix M. , Möller Martin , Schmaljohann Jörn
Published: February 2013

An efficient and simple synthesis approach to form stable 68Ga‐labeled nanogels is reported and their fundamental properties investigated. Nanogels are obtained by self‐assembly of amphiphilic statistical prepolymers derivatised with chelating groups for radiometals. The resulting nanogels exhibit a well‐defined spherical shape with a diameter of 290 ± 50 nm. The radionuclide 68Ga is chelated in high radiochemical yields in an aqueous medium at room temperature. The phagocytosis assay demonstrates a highly increased internalization of nanogels by activated macrophages. Access to these 68Ga‐nanogels will allow the investigation of general behavior and clearance pathways of nanogels in vivo by nuclear molecular imaging.

magnified image
Early postsurgical visualization of composite mesh used in ventral hernia repair by amide proton transfer MRI
Authors: Franconi Florence , Roux Jérome , Garric Xavier , Lemaire Laurent
Published: February 2013

Purpose

The feasibility of noninvasive visualization of composite meshes used in ventral hernia repair by amide‐proton transfer magnetic resonance imaging (APT‐MRI) was explored.

Methods

Magnetization transfer asymmetry ratio images of composite meshes were obtained in vitro and in vivo from fast‐spin echo acquisitions with frequency saturation offsets of ±3.5 ppm with respect to water frequency and no saturation. Three rats were assessed with APT‐MRI each week for 1 month after the intraperitoneal implantation of two meshes, one on each side of the incision. One mesh was coated with collagen and the other was not.

Results

In vitro, meshes were delineated with APT‐MRI as a thin continuous linear hypersignal located on one side of the mesh. Unlike collagen‐free meshes, collagen‐coated meshes were easily identified in vivo with APT‐MRI during the first 3 weeks postimplantation. The composite meshes magnetization transfer asymmetry ratio (8.7 ± 2.8%) were significantly different from the muscle magnetization transfer asymmetry ratio value (−0.9 ± 1.6%). After a month, the mesh value dropped down to 1.1 ± 3.9%. Muscle and mesh magnetization transfer asymmetry ratio values were not significantly different and mesh conspicuity was no longer possible.

Conclusion

The results suggest that APT‐MRI is a promising technique for noninvasive, early postsurgical visualization of composite meshes used in ventral hernia repair. Magn Reson Med 71:313–317, 2014. © 2013 Wiley Periodicals, Inc.
Media relations in the Council of the European Union: insights into the Council press officers' professional practices
Authors: Laursen Bo , Valentini Chiara
Published: February 2013

Government communication plays a key role in democratic societies as it helps public understanding of government policies and raises awareness of the roles and actions of decision makers. Within the European Union (EU) polity, communication plays a crucial role for citizens' support for the European integration process. Despite the increasing relevance of communication about major activities of the EU, studies on the EU institutions' communications are scarce, and very little is currently known about the external communication of the Council of the EU. Focusing on the media relations activities of the Council, this paper investigates the communication practices and roles of press officers working in the Council's General Secretariat as perceived by these government communicators themselves. Qualitative interviews with the press officers, analysis of Council documents, participation in their work processes and observations of their professional behaviour were used to establish the empirical basis of the study. The findings highlight the apolitical and reactive nature of these European civil servants' communication activities and identify some of the institutional and political challenges that they face in the performance of their professional duties. Copyright © 2013 John Wiley & Sons, Ltd.
Das naturwissenschaftliche Gymnasium, ein Versuch (Teil II)
Authors: Brüche E.
Published: February 2013

Der erste Teil dieses Aufsatzes erschien in Heft 2; er beschrieb die Grundgedanken und den versuchsweisen Aufbau eines naturwissenschaftlichen Gymnasiums unter den schwierigen und einengenden Verhältnissen der damaligen Zeit. Der zweite Teil bringt die Einzelheiten über die Art und die Methodik des Unterrichts sowie über die Erfahrungen, die in der kurzen Frist des Versuchs gemacht werden konnten. Der Verfasser zeigt, daß einige der Erfahrungen beim Neuaufbau der Höheren Schule nicht übersehen werden sollten. In einem dritten Teil, der in einem der folgenden Hefte veröffentlicht werden soll, werden noch einige Urteile von Schulleitern, und Schülern besprochen werden.
Historisches zu den Uranarbeiten in Deutschland in den Jahren 1940–1945
Authors: Wirtz K.
Published: February 2013

Am 5. September 1947 hielt Dozent Dr. K. Wirtz auf der Physikertagung der Deutschen Physikalischen Gesellschaft in der Britischen Zone in einem zusammenfassenden Bericht einen Vortrag mit dem Titel, Deutsche Vorarbeiten zur Konstruktion eines Uranbrenners' mit dem Untertitel, Historisches zu den Uranarbeiten in Deutschland in den Jahren 1940—1945. Fast gleichzeitig mit diesem Vortrag erschienen Veröffentlichungen zu diesem Gegenstand von Prof W Heisenberg in den Naturwissenschaften 33 (1947) S. 325 sowie in Nature 160 (1947) S. 211 und von Dr. Wirtz in der Göttinger Universitäts‐Zeitung 2 (1947) Nr. 20. Beide Herren haben ferner gemeinsam einen ausführlichen Bericht über die Ergebnisse der Großversuche für die FIAT Review geschrieben. der in Teil II des Bandes „KERNPHYSIK UND KOSMISCHE STRAHLUNG”︁ der Serie „Naturwissenschaft und Medizin in Deutschland, 1939—1946”︁ im Dieterich'schen Verlag, Wiesbaden, erscheint und die Einzelheiten der Experimente mitteilt. Der Tagungsvortrag von Dr. Wirtz stellte eine gekürzte Fassung des FIAT‐Berichtes dar und gab, ebenso wie die übrigen Veröffentlichungen, einen historischen Rückblick. Heute wird in Deutschland nicht mehr über diese Probleme gearbeitet. Wir bringen im folgenden aus diesem Vortrag einen Auszug, der mit freundlicher Erlaubnis der FIAT‐Dienststellen durch einige Zusätze aus dem FIAT‐Bericht ergänzt wurde.
Nordlichtbeobachtungen im südlichen Norwegen
Authors: Störmer C.
Published: February 2013

Prof. Störmer, der Leiter des Instituts für theoretische Astrophysik, Universität Oslo, wurde im Mai 1947 zum Ehrendoktor der Universität Oxfort, England, promoviert, wo er am 20. Mai die Halley‐Lecture über die Entwicklung der Nordlichtforschung hielt. Prof. Störmer, der sich seit mehr als 50 Jahren der Nordlicht‐Forschung verschrieben hat, dürfte der einzige Wissenschaftler der Welt sein, der die im Auftreten und ihren Formen unberechenbare Aurora Polaris “meine kapriziöse Freundin” zu nennen ein Recht hat.
Das Massenverhältnis von Proton und Elektron
Authors: Mecke R.
Published: February 2013

Betrachtungen über „Dimensionen”︁ und „natürliche Maßsysteme”︁ haben von jeher das Anrecht spekulativ zu sein. Nur so konnten sie die Ideenwelt der Physik bereichern und Wege ins Neuland zeigen. Mögen sich diese nur zu oft auch als Irrwege herausgestellt haben, sie waren trotzdem nicht umsonst gegangen, selbst wenn die Ausbeute an neuer Erkenntnis noch so klein war. So möge auch der folgende Beitrag als ein derartiger Wegweiser zu vielleicht neuen Zielen aufgefaßt werden.
Was ist Glas?
Authors: Jones G. O. , Simon F. E.
Published: February 2013

Vom Standpunkt der theoretischen Thermodynamik aus wird keiner der Begriffe „fest”︁, „flüssig”︁ oder „unterkühlte Flüssigkeit”︁ dem Zustand und den Eigenschaften von glasartigen Substanzen gerecht. In Wirklichkeit ist „Glas”︁ eine nicht‐thermodynamische Phase. Die Verfasser zeigen, daß ein Verständnis dieses Sachverhaltes wesentlich ist zur Erklärung der einzigartigen Eigenschaften von Gläsern und für das Verständnis des Dritten Hauptsatzes der Thermodynamik. Die Übertragung erfolgte mit freundlicher Genehmigung der Autoren und des Verlages aus ENDEAVOUR 8 (1949) Nr. 32.
Entwicklung, Stand und Aussichten einer mathematischen Wettervorhersage
Authors: Flohn Hermann
Published: February 2013

In den Tagen vom 23. bis 28. Mai 1956 trafen sich auf Einladung der Deutschen Meteorologischen Gesellschaft (Zweigverein Frankfurt/M.) rund 35 Fachleute aus 12 Ländern zu einer Konferenz über Fragen der numerischen Wettervorhersage in Frankfurt/Main. In zahlreichen Vorträgen und Diskussionen wurden die bisherigen Resultate der laufenden Großversuche in Schweden (seit Nov. 1954) und den USA (seit Mai 1955) erörtert, die theoretischen Grundlagen der Weiterentwicklung und das Forschungsprogramm besprochen. Es war die zweite europäische Konferenz dieser Art, nachdem die erste im Herbst 1952 unter dem Vorsitz von C. G. Rossby in Stockholm stattgefunden hatte. Fast alle Arbeitsgruppen waren vertreten (einschließlich Meteorologen aus Reykjavik, Potsdam und Prag), nur die japanische Gruppe mußte sich wegen der Entfernung auf Übersendung von Manuskripten und Verteilung von Arbeitsberichten beschränken. Die in ausgezeichneter Stimmung durchgeführte Konferenz stand im Zeichen sorgfältiger und sachlicher, stets freundschaftlicher Kritik der bisherigen Methoden, die aber das optimistische Gesamturteil über die Aussichten der mathematischen Wettervorhersage innerhalb der erreichbaren Grenzen nur noch unterstrich.
Hat die Saarbrücker Rahmenvereinbarung ihr pädagogisches Ziel erreicht?/Resolution zur Saarbrücker Rahmenvereinbarung/Lehrermangel in Mathematik und Naturwissenschaften
Authors: Knievel Fritz
Published: February 2013

„Die Verminderung der Zahl der Pflichtfächer und die Konzentration der Bildungsstoffe werden eine Vertiefung des Unterrichts ermöglichen und die Erziehung des Schülers zu geistiger Selbsttätigkeit und Verantwortung fördern. Damit werden die Grundlagen zu einer besonderen Arbeitsweise geschaffen, die … der Oberstufe eine eigene Prägung gibt.”︁ (Aus dem Text der Rahmenvereinbarung von Saarbrücken vom 29. September 1960)