bluuebunny/crossref_metadata_2025 huggingface dataset:
A Dual Small‐Molecule Rheostat for Precise Control of Protein Concentration in Mammalian Cells
Authors: Lin Yu Hsuan , Pratt Matthew R.
Published: March 2014

One of the most successful strategies for controlling protein concentrations in living cells relies on protein destabilization domains (DD). Under normal conditions, a DD will be rapidly degraded by the proteasome. However, the same DD can be stabilized or “shielded” in a stoichiometric complex with a small molecule, enabling dose‐dependent control of its concentration. This process has been exploited by several labs to post‐translationally control the expression levels of proteins in vitro as well as in vivo, although the previous technologies resulted in permanent fusion of the protein of interest to the DD, which can affect biological activity and complicate results. We previously reported a complementary strategy, termed traceless shielding (TShld), in which the protein of interest is released in its native form. Here, we describe an optimized protein concentration control system, TTShld, which retains the traceless features of TShld but utilizes two tiers of small molecule control to set protein concentrations in living cells. These experiments provide the first protein concentration control system that results in both a wide range of protein concentrations and proteins free from engineered fusion constructs. The TTShld system has a greatly improved dynamic range compared to our previously reported system, and the traceless feature is attractive for elucidation of the consequences of protein concentration in cell biology.
Risk and resiliency factors influencing onset and adolescence‐limited commercial sexual exploitation of disadvantaged girls
Authors: Reid Joan A.
Published: March 2014

Background

Previous research into age‐related variables relevant to girls and young women being involved in commercial sexual exploitation (including prostitution) has not distinguished between its onset and limitation to adolescence and its early onset and persistence into adult life.

Aims

The aims of this study were to examine variables associated with adolescent versus adult onset of commercial sexual exploitation and identify potential risk and resiliency factors differentiating adolescence‐limited sexual exploitation and early‐onset‐adult persistent exploitation.

Method

Interviews with 174 vulnerable mostly African‐American women, 23% of whom reported commercial sexual exploitation in adolescence and/or adulthood, yielded data, which were analysed using multinomial logistic regressions.

Results

Adolescent sexual victimisation, younger age at first alcohol/drug use, being a victim of intimate partner violence and sense of stigmatisation of sexual self/others were all variables associated with adolescent onset of commercial sexual exploitation. Educational attainment differentiated adolescence limited from adolescent‐adult persistent exploitation; exploitation had ceased by adulthood among over two‐thirds of those who completed at least high school education, but only 13% of those exploited into adult life had finished high school.

Conclusions and implications for practice

As level of education was linked to cessation of exploitation by adulthood, support for vulnerable girls to complete education at least to high school level may be protective.

The link between early onset of substance misuse and persistent exploitation suggests that education and support specifically targeted within this field could reduce likelihood of persistent abuse.

Work directed at improvement of self‐image may also reduce risk of persistent exploitation. Copyright © 2014 John Wiley & Sons, Ltd.
Oxygen‐Terminated Diamond Electrodes in Alkaline Media: Structure and OH Generation
Authors: Quaino Paola M. , Schmickler Wolfgang
Published: March 2014

The structure and energetics of two types of oxygen‐terminated diamond surfaces, the keto and ether configurations, were investigated by density functional theory. To explore OH generation, we studied the approach of a hydroxyl radical to these surfaces. The OH radical strongly interacted with the ether‐type surface, whereas the radical was repelled in the keto configuration. The kinetics of OH generation in alkaline solutions (OH−↔OH+e−) on oxygen‐terminated diamond electrodes was investigated in light of the theory of catalyzed electron transfer. Our results suggested that the electron transfer occurs in the outer‐sphere mode with an activation energy of 0.5 eV.
Utilizing Chromium as the Photoanode Substrate in Dye‐Sensitized Solar Cells
Authors: Behrouznejad Fatemeh , Taghavinia Nima
Published: March 2014

Fluorine‐doped tin oxide (FTO) is replaced with chromium as the photoanode substrate in a dye‐sensitized solar cell (DSSC), and the effect of chromium(III) oxide on the electron lifetime and the performance of a Cr‐based DSSC is investigated and compared with conventional FTO‐based devices. It is shown that Cr is stable in the chemically aggressive iodide‐based electrolyte, which can be attributed to the compact oxide overlayer. The chromium‐oxide layer also effectively blocks electron recombination from the substrate, while hindering electron transfer from the TiO2 film to the Cr electrode. We show that pretreatment of the electrodeposited Cr film with a colloidal sol of TiO2 is extremely effective in reducing the electron‐transfer resistance at the Cr–TiO2 interface. This effect may be attributed to both increasing interconnections between the mesoporous layer of TiO2 and the rough electrodeposited layer of Cr, as well as inhibition of the thickening Cr2O3 layer during the thermal process. The colloidal sol treatment increases the cell efficiency by 73 % of the initial value (from 2.58 to 4.47 %) and the fill factor from 0.38 to 0.64.
Correlation of Insulin‐Enhancing Properties of Vanadium‐Dipicolinate Complexes in Model Membrane Systems: Phospholipid Langmuir Monolayers and AOT Reverse Micelles
Authors: Sostarecz Audra G. , Gaidamauskas Ernestas , Distin Steve , Bonetti Sandra J. , Levinger Nancy E. , Crans Debbie C.
Published: March 2014

We explore the interactions of VIII‐, VIV‐, and VV‐2,6‐pyridinedicarboxylic acid (dipic) complexes with model membrane systems and whether these interactions correlate with the blood‐glucose‐lowering effects of these compounds on STZ‐induced diabetic rats. Two model systems, dipalmitoylphosphatidylcholine (DPPC) Langmuir monolayers and AOT (sodium bis(2‐ethylhexyl)sulfosuccinate) reverse micelles present controlled environments for the systematic study of these vanadium complexes interacting with self‐assembled lipids. Results from the Langmuir monolayer studies show that vanadium complexes in all three oxidation states interact with the DPPC monolayer; the VIII–phospholipid interactions result in a slight decrease in DPPC molecular area, whereas VIV and VV–phospholipid interactions appear to increase the DPPC molecular area, an observation consistent with penetration into the interface of this complex. Investigations also examined the interactions of VIII‐ and VIV‐dipic complexes with polar interfaces in AOT reverse micelles. Electron paramagnetic resonance spectroscopic studies of VIV complexes in reverse micelles indicate that the neutral and smaller 1:1 VIV‐dipic complex penetrates the interface, whereas the larger 1:2 VIV complex does not. UV/Vis spectroscopy studies of the anionic VIII‐dipic complex show only minor interactions. These results are in contrast to behavior of the VV‐dipic complex, [VO2(dipic)]−, which penetrates the AOT/isooctane reverse micellar interface. These model membrane studies indicate that VIII‐, VIV‐, and VV‐dipic complexes interact with and penetrate the lipid interfaces differently, an effect that agrees with the compounds’ efficacy at lowering elevated blood glucose levels in diabetic rats.
Highly Luminescent and Color‐Tunable Salicylate Ionic Liquids
Authors: Campbell Paul S. , Yang Mei , Pitz Demian , Cybinska Joanna , Mudring Anja‐Verena
Published: March 2014

High quantum yields of up to 40.5 % can be achieved in salicylate‐bearing ionic liquids. A range of these ionic liquids have been synthesized and their photoluminescent properties studied in detail. The differences noted can be related back to the structure of the ionic liquid cation and possible interionic interactions. It is found that shifts of emission, particularly in the pyridinium‐based ionic liquids, can be related to cation–anion pairing interactions. Facile and controlled emission color mixing is demonstrated through combining different ILs, with emission colors ranging from blue to yellow.
The Protoelectric Potential Map (PPM): An Absolute Two‐Dimensional Chemical Potential Scale for a Global Understanding of Chemistry
Authors: Radtke Valentin , Himmel Daniel , Pütz Katharina , Goll Sascha K. , Krossing Ingo
Published: March 2014

We introduce the protoelectric potential map (PPM) as a novel, two‐dimensional plot of the absolute reduction potential (peabs scale) combined with the absolute protochemical potential (Brønsted acidity: pHabs scale). The validity of this thermodynamically derived PPM is solvent‐independent due to the scale zero points, which were chosen as the ideal electron gas and the ideal proton gas at standard conditions. To tie a chemical environment to these reference states, the standard Gibbs energies for the transfer of the gaseous electrons/protons to the medium are needed as anchor points. Thereby, the thermodynamics of any redox, acid–base or combined system in any medium can be related to any other, resulting in a predictability of reactions even over different media or phase boundaries. Instruction is given on how to construct the PPM from the anchor points derived and tabulated with this work. Since efforts to establish “absolute” reduction potential scales and also “absolute” pH scales already exist, a short review in this field is given and brought into relation to the PPM. Some comments on the electrochemical validation and realization conclude this concept article.
Synthesis of 18F‐Labelled β‐Lactams by Using the Kinugasa Reaction
Authors: Zlatopolskiy Boris D. , Krapf Philipp , Richarz Raphael , Frauendorf Holm , Mottaghy Felix M. , Neumaier Bernd
Published: March 2014

Owing to their broad spectrum of biological activities and low toxicity, β‐lactams are attractive lead structures for the design of novel molecular probes. However, the synthesis of positron emission tomography (PET)‐isotope‐labelled β‐lactams has not yet been reported. Herein, we describe the simple preparation of radiofluorinated β‐lactams by using the fast Kinugasa reaction between 18F‐labelled nitrone [18F]‐1 and alkynes of different reactivity. Additionally, 18F‐labelled fused β‐lactams were obtained through the reaction of a cyclic nitrone 7 with radiofluorinated alkynes [18F]‐6 a,b. Radiochemical yields of the Kinugasa reaction products could be significantly increased by the use of different CuI ligands, which additionally allowed a reduction in the amount of precursor and/or reaction time. Model radiofluorinated β‐lactam‐peptide and protein conjugates ([18F]‐10 and 18F‐labelled BSA conjugate) were efficiently obtained in high yield under mild conditions (aq. MeCN, ambient temperature) within a short reaction time, demonstrating the suitability of the developed method for radiolabelling of sensitive molecules such as biopolymers.
Synthesis and Transformations of 5‐Chloro‐2,2′‐Dipyrrins and Their Boron Complexes, 8‐Chloro‐BODIPYs
Authors: Wang Haijun , Vicente M. Graça H. , Fronczek Frank R. , Smith Kevin M.
Published: March 2014

Symmetric dipyrrylketones 1 a,b were synthesized in two steps from the corresponding α‐free pyrroles, by reaction with thiophosgene followed by oxidative hydrolysis under basic conditions. The dipyrrylketones produced the corresponding 5‐chloro‐dipyrrinium salts or 5‐ethoxy‐dipyrrins on reaction with phosgene or Meerwein’s salt, respectively. Boron complexation of the dipyrrins afforded the corresponding 8‐functionalized BODIPYs (borondipyrromethenes) in high yields. The 5‐chloro‐dipyrrinium salts reacted with methoxide or ethoxide ions to produce monopyrrole esters, presumably via a 5,5‐dialkoxy‐dipyrromethane intermediate. In contrast, 8‐chloro‐BODIPYs underwent a variety of nucleophilic substitutions of the chloro group in the presence of alkoxide ions, Grignard reagents, and thiols. In the presence of excess alkoxide or Grignard reagent, at room temperature or above, substitution at the boron center also occurred. The 8‐chloro‐BODIPY was a particularly useful reagent for the preparation of 8‐aryl‐, 8‐alkyl‐, and 8‐vinyl‐substituted BODIPYs in very high yields, using Pd0‐catalyzed Stille cross‐coupling reactions. The X‐ray structures of eleven BODIPYs and two pyrroles are presented, and the spectroscopic properties of the synthesized BODIPYs are discussed.
Near‐Infrared‐Light‐Driven Artificial Photosynthesis by Nanobiocatalytic Assemblies
Authors: Lee Joon Seok , Nam Dong Heon , Kuk Su Keun , Park Chan Beum
Published: March 2014

Artificial photosynthesis in nanobiocatalytic assemblies aims to reconstruct man‐made photosensitizers, electron mediators, electron donors, and redox enzymes for solar synthesis of valuable chemicals through photochemical cofactor regeneration. Herein, we report, for the first time, on nanobiocatalytic artificial photosynthesis in near‐infrared (NIR) light, which constitutes over 46% of the solar energy. For NIR‐light‐driven photoenzymatic synthesis, we synthesized silica‐coated upconversion nanoparticles, Si‐NaYF4:Yb,Er and Si‐NaYF4:Yb,Tm, for efficient photon‐conversion through Förster resonance energy transfer (FRET) with rose bengal (RB), a photosensitizer. We observed NIR‐induced electron transfer by using linear sweep voltammetric analysis; this indicates that photoexcited electrons of RB/Si‐NaYF4:Yb,Er are transferred to NAD+ through a Rh‐based electron mediator. RB/Si‐NaYF4:Yb,Er nanoparticles, which exhibit higher FRET efficiency due to more spectral overlap than RB/Si‐NaYF4:Yb,Tm, perform much better in the photoenzymatic conversion.
Autonomous and in trans functions for the two halves of Srv2/CAP in promoting actin turnover
Authors: Chaudhry Faisal , Jansen Silvia , Little Kristin , Suarez Cristian , Boujemaa‐Paterski Rajaa , Blanchoin Laurent , Goode Bruce L.
Published: March 2014

Recent evidence has suggested that Srv2/CAP (cyclase‐associated protein) has two distinct functional roles in regulating actin turnover, with its N‐terminus enhancing cofilin‐mediated severing of actin filaments and its C‐terminus catalyzing actin monomer recycling. However, it has remained unclear to what degree these two activities are coordinated by being linked in one molecule, or whether they can function autonomously. To address this, we physically divided the protein into two separate halves, N‐Srv2 and C‐Srv2, and asked whether they are able to function in trans both in living cells and in reconstituted assays for F‐actin turnover and actin‐based motility. Remarkably, in F‐actin turnover assays the stimulatory effects of N‐Srv2 and C‐Srv2 functioning in trans were quantitatively similar to those of intact full‐length Srv2. Further, in bead motility assays and in vivo, the fragments again functioned in trans, although not with the full effectiveness of intact Srv2. From these data, we conclude that the functions of the two halves of Srv2/CAP are largely autonomous, although their linkage improves coordination of the two functions in specific settings, possibly explaining why the linkage is conserved across distant plant, animal, and fungal species. © 2014 Wiley Periodicals, Inc.
In silico Design, Synthesis, and Screening of Novel Deoxyhypusine Synthase Inhibitors Targeting HIV‐1 Replication
Authors: Schroeder Marcus , Kolodzik Adrian , Pfaff Katharina , Priyadarshini Poornima , Krepstakies Marcel , Hauber Joachim , Rarey Matthias , Meier Chris
Published: March 2014

The human enzyme deoxyhypusine synthase (DHS) is an important host cell factor that participates in the post‐translational hypusine modification of eukaryotic initiation factor 5A (eIF‐5A). Hypusine‐modified eIF‐5A plays a role in a number of diseases, including HIV infection/AIDS. Thus, DHS represents a novel and attractive drug target. So far, four crystal structures are available, and various substances have been tested for inhibition of human DHS. Among these inhibitors, N‐1‐guanyl‐1,7‐diaminoheptane (GC7) has been co‐crystallized in the active site of DHS. However, despite its potency, GC7 is not selective enough to be used in drug applications. Therefore, new compounds that target DHS are needed. Herein we report the in silico design, chemical synthesis, and biological evaluation of new DHS inhibitors. One of these inhibitors showed dose‐dependent inhibition of DHS in vitro, as well as suppression of HIV replication in cell cultures. Furthermore, the compound exhibited no cytotoxic effects at active concentrations. Thus, this designed compound demonstrated proof of principle and represents a promising starting point for the development of new drug candidates to specifically interfere with DHS activity.
The DiPPro Approach: Synthesis, Hydrolysis, and Antiviral Activity of Lipophilic d4T Diphosphate Prodrugs
Authors: Schulz Tilmann , Balzarini Jan , Meier Chris
Published: March 2014

Bioreversible protection of the β‐phosphate group of nucleoside diphosphates (NDPs) as bis(acyloxybenzyl)phosphate esters is presented. To investigate the structure–activity relationship of these potential NDP prodrugs (DiPPro drugs) a series of DiPPro compounds was synthesized bearing fatty acids of various lengths and d4T as a model nucleoside. For synthesis of the lipophilically modified diphosphate group, preformed phosphoramidites were allowed to react with nucleotides, and the β‐PIII moiety was subsequently oxidized. The chemical and enzymatic stability of these prodrugs was studied in different media such as phosphate buffer (pH 7.3) or CEM cell extracts. In all media, the hydrolysis rate was clearly dependent on the acyl moiety and decreased with increasing alkyl chain length. The compounds showed a markedly lower half‐life in cell extracts than in pH 7.3 phosphate buffer due to the presence of enzyme‐catalyzed cleavage. In all media, the DiPPro compounds released d4T diphosphate (d4TDP) as the main product beside d4TMP. In antiviral assays, the compounds proved to be at least as potent as d4T against HIV‐1 and 2 in wild‐type CEM/0 cells. As a proof of concept, compounds with longer acyl residues showed very good anti‐HIV activities in thymidine‐kinase‐deficient cells (CEM/TK−), indicating their ability to penetrate cell membranes and the delivery of phosphorylated metabolites.
SpiroZin1: A Reversible and pH‐Insensitive, Reaction‐Based, Red‐Fluorescent Probe for Imaging Biological Mobile Zinc
Authors: Rivera‐Fuentes Pablo , Lippard Stephen J.
Published: March 2014

A reversible, reaction‐based sensor for biological mobile zinc was designed, prepared, and characterized. The sensing mechanism of this probe is based on the zinc‐induced, ring‐opening reaction of spirobenzopyran to give a cyanine fluorophore that emits in the deep‐red region of the electromagnetic spectrum. This probe is not activated by protons and operates efficiently in aqueous solution at pH 7 and high ionic strength. The mechanism of this reaction was studied by using a combination of kinetics experiments and DFT calculations. The biocompatibility of the probe was demonstrated in live HeLa cells.
The effects of CYP3A4 induction and inhibition on the pharmacokinetics of alisporivir in humans
Authors: Barve Avantika , Kovacs Steven J. , Ke June , Crabbe Rafael , Grosgurin Peter , Menetrey Annick , Nicolas‐Métral Valerie , Dabovic Kristina , Dole Kiran , Zhang Jie , Praestgaard Jens , Sunkara Gangadhar , Stein Daniel
Published: March 2014

In vitro data suggest that alisporivir is a substrate and inhibitor of CYP3A4 and P‐gp. Hence, the potential for drug–drug interactions when alisporivir is co‐administered with CYP3A4 and/or P‐gp inhibitors such as ketoconazole, azithromycin and CYP3A4 inducers such as rifampin were evaluated in three separate clinical studies. Co‐administration with ketoconazole (a strong CYP3A4 inhibitor) increased the Cmax, AUC and terminal elimination half‐life of alisporivir by approximately two‐, eight‐ ,and threefold, respectively. Co‐administration with azithromycin (a putative weak CYP3A4 inhibitor and substrate) had no impact on the Cmax and AUC of alisporivir. Rifampin (a CYP3A4 inducer) caused an approximate 90% reduction in alisporivir Cmax and AUC and a fourfold reduction in alisporivir terminal elimination half‐life. Alisporivir as an inhibitor of CYP3A4 caused a 39% increase in azithromycin exposure. The results from these studies establish alisporivir as a sensitive CYP3A4 substrate in vivo. Consequently, co‐administered potent CYP3A4 inhibitors and inducers are likely to cause clinically significant changes in the exposure to alisporivir.
Effect of canagliflozin, a sodium glucose co‐transporter 2 inhibitor, on C‐peptide kinetics
Authors: Polidori David , Sha Sue , Heise Tim , Natarajan Jaya , Artis Eunice , Wang Shean‐Sheng , Vaccaro Nicole , Rothenberg Paul , Stirban Alin
Published: March 2014

Canagliflozin, a sodium glucose co‐transporter 2 inhibitor, improves indices of β‐cell function estimated based on circulating C‐peptide and glucose concentrations (e.g., Homeostasis Model Assessment [HOMA2‐%B], meal tolerance test‐based indices). However, use of these β‐cell function indices assumes C‐peptide kinetics are not altered by canagliflozin. This 2‐period crossover study assessed the effect of a single canagliflozin 300‐mg dose on C‐peptide kinetics in 10 healthy participants. Two hours after receiving canagliflozin or placebo, participants received intravenous somatostatin infusion to suppress endogenous C‐peptide secretion and 1 hour later received a bolus injection of synthetic human C‐peptide 150 µg. Serum C‐peptide was measured over 3 hours and urinary glucose and C‐peptide excretion were measured. C‐peptide kinetic parameters, including total clearance (CLtotal) and renal clearance (CLrenal), were calculated. Serum C‐peptide profiles were similar following canagliflozin or placebo treatment. C‐peptide CLtotal was slightly lower with canagliflozin versus placebo (mean (SD) of 190 (37) vs. 197 (30) mL/min; canagliflozin/placebo ratio [90% CI] = 96.1% [93.0%; 99.3%]). Other kinetic parameters, including CLrenal, were generally similar between treatments. Results indicate canagliflozin 300 mg does not meaningfully alter C‐peptide clearance or other kinetic parameters; therefore, C‐peptide–based measurements of insulin secretion are appropriate for assessing β‐cell function in canagliflozin‐treated participants.
Mechanism of Dissolution of a Lithium Salt in an Electrolytic Solvent in a Lithium Ion Secondary Battery: A Direct Ab Initio Molecular Dynamics (AIMD) Study
Authors: Tachikawa Hiroto
Published: March 2014

The mechanism of dissolution of the Li+ ion in an electrolytic solvent is investigated by the direct ab initio molecular dynamics (AIMD) method. Lithium fluoroborate (Li+BF4−) and ethylene carbonate (EC) are examined as the origin of the Li+ ion and the solvent molecule, respectively. This salt is widely utilized as the electrolyte in the lithium ion secondary battery. The binding of EC to the Li+ moiety of the Li+BF4− salt is exothermic, and the binding energies at the CAM–B3LYP/6‐311++G(d,p) level for n=1, 2, 3, and 4, where n is the number of EC molecules binding to the Li+ ion, (EC)n(Li+BF4−), are calculated to be 91.5, 89.8, 87.2, and 84.0 kcal mol−1 (per EC molecule), respectively. The intermolecular distances between Li+ and the F atom of BF4− are elongated: 1.773 Å (n=0), 1.820 Å (n=1), 1.974 Å (n=2), 1.942 Å (n=3), and 4.156 Å (n=4). The atomic bond populations between Li+ and the F atom for n=0, 1, 2, 3, and 4 are 0.202, 0.186, 0.150, 0.038, and 0.0, respectively. These results indicate that the interaction of Li+ with BF4− becomes weaker as the number of EC molecules is increased. The direct AIMD calculation for n=4 shows that EC reacts spontaneously with (EC)3(Li+BF4−) and the Li+ ion is stripped from the salt. The following substitution reaction takes place: EC+(EC)3(Li+BF4−)→(EC)4Li+−(BF4−). The reaction mechanism is discussed on the basis of the theoretical results.
Biopolymer‐Supported Ionic‐Liquid‐Phase Ruthenium Catalysts for Olefin Metathesis
Authors: Clousier Nathalie , Filippi Alexandra , Borré Etienne , Guibal Eric , Crévisy Christophe , Caijo Fréderic , Mauduit Marc , Dez Isabelle , Gaumont Annie‐Claude
Published: March 2014

Original ruthenium supported ionic liquid phase (SILP) catalysts based on alginates as supports were developed for olefin metathesis reactions. The marine biopolymer, which fulfills most of the requisite properties for a support such as widespread abundance, insolubility in the majority of organic solvents, a high affinity for ionic liquids, high chemical stability, biodegradability, low cost, and easy processing, was impregnated by [bmim][PF6] containing an ionically tagged ruthenium catalyst. These biosourced catalysts show promising performances in ring‐closing metathesis (RCM) and cross‐metathesis (CM) reactions, with a high level of recyclability and reusability combined with a good reactivity.
Cerium‐Based Binary and Ternary Oxides in the Transesterification of Dimethylcarbonate with Phenol
Authors: Dibenedetto Angela , Angelini Antonella , di Bitonto Luigi , De Giglio Elvira , Cometa Stefania , Aresta Michele
Published: March 2014

Diphenyl carbonate (DPC) plays a key role in phosgene‐free carbonylation processes. It can be produced by transesterification of dimethyl carbonate (DMC) with phenol in the presence of catalysts. Methyl phenyl carbonate (MPC) is first produced that is then converted into DPC by either disproportionation or further transesterification with phenol. Cerium‐based bimetallic oxides (with the heterometal being niobium, iron, palladium, or aluminum) are used as catalysts in the transesterification of DMC to synthesize MPC. The catalytic activity is affected by the type and concentration of the heterometal. XPS, IR and elementary analyses are employed to characterize the new catalysts. Differently from pure oxides, the mixed oxides produce a significant increase of the conversion and selectivity towards MPC.
Solid Catalysts for Multistep Reactions: One‐Pot Synthesis of 2,3‐Dihydro‐1,5‐benzothiazepines with Solid Acid and Base Catalysts
Authors: Climent Maria J. , Corma Avelino , Iborra Sara , Martí Laura
Published: March 2014

1,5‐Benzothiazepines derivatives were obtained first by starting from 1,3‐diphenylpropenone derivatives (chalcones) and 2‐aminothiophenol by using aluminosilicate solid catalysts. However, diffusional limitations and the strong adsorption of products on the catalyst are deleterious for catalyst activity and life. Then a structured amorphous mesoporous catalyst with large pores and mild acidity that works at higher temperatures allowed us to obtain high conversions (99 %) and selectivities (98 %) of the desired product. A one‐pot synthesis of 1,5‐benzothiazepines that starts from benzaldehyde, acetophenone, and 2‐aminothiophenol with 95 % yield was performed by combining optimized solid base and acid catalysts in batch mode as well as in a continuous‐flow reactor system. Much better conversion and selectivity as well as process intensification has been achieved with the structured mesoporous materials by avoiding intermediate and final neutralization and purification steps required in the synthesis reported previously that uses homogeneous catalysts.
B‐type suppression: A role played by “regulatory B cells” or “regulatory plasma cells”?
Authors: Ries Stefanie , Hilgenberg Ellen , Lampropoulou Vicky , Shen Ping , Dang Van Duc , Wilantri Siska , Sakwa Imme , Fillatreau Simon
Published: March 2014

B‐cell depletion can improve disease in some patients with rheumatoid arthritis or multiple sclerosis, indicating the pathogenic contribution of B cells to autoimmunity. However, studies in mice have demonstrated that B cells have immunosuppressive functions as well, with IL‐10 being a critical mediator of B‐cell‐mediated suppression. IL‐10‐secreting B cells have been shown to promote disease remission in some mouse models of autoimmune disorders. Human B cells also produce IL‐10, and evidence is accumulating that human IL‐10‐producing B cells might inhibit immunity. There is considerable interest in identifying the phenotype of B cells providing IL‐10 in a suppressive manner, which would facilitate the analysis of the molecular mechanisms controlling this B‐cell property. Here, we review current knowledge on the B‐cell subpopulations found to provide suppressive functions in mice, considering both the pathological context in which they were identified and the signals that control their induction. We discuss the phenotype of B cells that have IL‐10‐dependent regulatory activities in mice, which leads us to propose that antibody‐secreting cells are, in some cases at least, the major source of B‐cell‐derived regulatory IL‐10 in vivo. Anti‐inflammatory cytokine production by antibody‐secreting cells offers a novel mechanism for the coordination of innate and humoral immune responses.
Bulky Titanium Amides: C–H Bond Activation under Mild Conditions
Authors: Adler Christian , Bekurdts Alexander , Haase Detlev , Saak Wolfgang , Schmidtmann Marc , Beckhaus Rüdiger
Published: March 2014

Invited for the cover of this issue is the group of Rüdiger Beckhaus at the University of Oldenburg. The cover image shows a series of titanium amide complexes synthesized in the group’s lab. These compounds undergo spontaneous C–H bond activation reactions under mild conditions. The background of the cover picture shows the Science Campus of the University.
Acute lymphoblastic leukemia with low hypodiploid/near triploid karyotype is a specific clinical entity and exhibits a very high TP53 mutation frequency of 93%
Authors: Mühlbacher Verena , Zenger Melanie , Schnittger Susanne , Weissmann Sandra , Kunze Franziska , Kohlmann Alexander , Bellos Frauke , Kern Wolfgang , Haferlach Torsten , Haferlach Claudia
Published: March 2014

B lymphoblastic leukemia/lymphoma (ALL) are subdivided by the WHO classification into five subgroups defined by specific translocations and two further subgroups defined by the number of chromosomes. The hypodiploid subgroup is heterogeneous and comprises ALL with a chromosome number of <46. To characterize a specific subset with low hypodiploid karyotype, we performed chromosome banding analysis, FISH, array comparative genomic hybridization, and mutational analyses of FBXW7, NOTCH1, KRAS, NRAS, TP53, and IKZF1 in 29 cases. We observed a nonrandom pattern of chromosome losses, including chromosomes 3, 7, 13, 15, 16, and 17. A deletion encompassing the CDKN2A/B locus was the only recurrent structural abnormality. A duplication of the low hypodiploid karyotype occurred frequently, resulting in a near triploid karyotype based on the definition by merely counting chromosomes but in fact was a very low tetraploid chromosome set. Mutational analyses revealed no mutations in IKZF1, FBXW7, NOTCH1, and KRAS and only one mutation in NRAS. However, we discovered a high frequency of TP53 mutations in 93% (27/29) of cases. In 26/27 cases with TP53 mutation, the second TP53 allele was lost due to monosomy 17. Median overall survival was short (18.5 months), which might be related to the high frequency of TP53 alterations. Therefore, ALL with low hypodiploidy is characterized by a typical pattern of chromosome losses and a remarkably high TP53 mutation frequency. Our data suggest the introduction of a novel WHO entity within the B lymphoblastic leukemia/lymphoma group showing low hypodiploid/very low tetraploid karyotype and concomitant TP53 mutation. © 2014 Wiley Periodicals, Inc.
Squamous cell carcinoma of the tonsil managed by conventional surgery and postoperative radiation
Authors: Rahmati Rahmatullah , Dogan Snjezana , Pyke Owen , Palmer Frank , Awad Mahmoud , Lee Nancy , Kraus Dennis H. , Shah Jatin P. , Patel Snehal G. , Ganly Ian
Published: March 2014

Background

The purpose of this study was to report the long‐term outcome of patients with squamous cell cancer (SCC) of the tonsil managed by surgery followed by postoperative radiotherapy (PORT).

Methods

Eighty‐eight patients treated between 1985 and 2005 were analyzed. Overall survival (OS), disease‐specific survival (DSS), and recurrence‐free survival (RFS) were determined by the Kaplan–Meier method. Factors predictive of outcome were determined by univariate and multivariate analysis.

Results

Forty‐eight percent of patients had T3 to T4 disease and 75% had a positive neck. Five‐year OS, DSS, and RFS were 66%, 82%, and 80%, respectively. The status of the neck was not predictive of outcome (DSS 80% for N0 vs 82% for N+; p = .97). Lymphovascular invasion was an independent predictor of OS, DSS, and RFS on multivariate analysis.

Conclusion

Lymphovascular invasion but not pathological stage of the neck is an independent predictor of outcome in patients with tonsillar SCC. © 2014 Wiley Periodicals, Inc. Head Neck 37: 800–807, 2015
Intramolecular 1,2‐ and 1,3‐Hydrogen Transfer Reactions of Thiyl Radicals
Authors: Schöneich Christian , Mozziconacci Olivier , Koppenol Willem H. , Nauser Thomas
Published: March 2014

This review article summarizes recent experiments on 1,2‐ and 1,3‐hydrogen transfer reactions in thiyl radicals from cysteine and related compounds. Pulse radiolysis in combination with time‐resolved UV spectroscopy was applied to monitor the equilibration of initial thiyl radicals with carbon‐centered radicals at both the Cα and Cβ positions of cysteine. Experiments with thiyl radicals from penicillamine and cysteamine confirmed the formation of carbon‐centered radicals at these positions. Complementary evidence for the intermediary formation of carbon‐centered radicals was obtained from mass spectrometry and 1H NMR spectroscopy experiments, both of which indicated covalent H/D exchange at original CH bonds when thiyl radicals were generated in D2O. The 1,2‐ and 1,3‐hydrogen transfer reactions can have profound consequences for the integrity of proteins when Cys residues are oxidized to Cys thiyl radicals, which subsequently equilibrate with carbon‐centered radicals.
Sperm ultrastructure of Panorpodes kuandianensis (Mecoptera: Panorpodidae)
Authors: Zhang Beibei , Hua Baozhen
Published: March 2014

The sperm ultrastructure of the short‐faced scorpionfly Panorpodes kuandianensis Zhong et al. was investigated using transmission electron microscopy. The spermatozoon is composed of a short head containing a bilayered acrosome and an elongate nucleus, a neck transition region, and a long flagellum. The acrosome consists of an acrosomal vesicle and a central perforatorium. The nucleus has two deep, U‐shaped lateral grooves and its chromatin contains a series of parallel, regularly arrayed nuclear fibers. The barrel‐shaped centriolar adjunct occupies the most volume of the neck region. The flagellum is helical for its whole length and is formed by an axoneme, two mitochondrial derivatives, a pair of accessory bodies, and peculiar accessory structures. The axoneme has nine accessory microtubules at the anterior flagellum region, displaying a 9 + 9 + 2 microtubular pattern, but the accessory microtubules are short and disappear quickly. The two mitochondrial derivatives differ in length and diameter. In the more posterior region, the remaining anchor‐shaped mitochondrial derivative has a circular crystalline region, differing from other mecopteran species. The filiform materials are peculiar and lie beside the nucleus and in the flagellum region. Sperm ultrastructural comparison of P. kuandianensis with other families supports a close affinity of Panorpodidae with Panorpidae. In addition, the occurrence of the nine accessory microtubules in the sperm axoneme of Panorpodes indicates that the 9 + 9 + 2 axonemal pattern might be a symplesiomorphy of the Mecoptera. Microsc. Res. Tech. 77:394–400, 2014. © 2014 Wiley Periodicals, Inc.
Improvement of the chromatographic separation performance of an imidazolium ionic liquid functionalized silica column by in situ anion‐exchange with dodecyl sulfonate and dodecylbenzene sulfonate anions
Authors: Sun Min , Feng Juanjuan , Chen Wenjie , Li Leilei , Duan Huimin , Luo Chuannan
Published: March 2014

The anionic part of ionic liquids can provide additional interactions during chromatographic separations. In this work, the chromatographic separation performance of a silica column functionalized with 1‐propyl‐3‐methylimidazolium chloride ionic liquid was improved by in situ anion‐exchange from chloride anions to dodecyl sulfonate anions and dodecylbenzene sulfonate anions. The separation performances of these ionic liquid functionalized phases were investigated and compared with each other using polycyclic aromatic hydrocarbons, phthalates, parabens, and phenols as model compounds. Results indicated that the new columns presented a better chromatographic separation than the original one. This was ascribed retention mechanism from organic anions. The introduction of dodecyl sulfonate anions increased the hydrophobicity of stationary phase. Furthermore, the phenyl groups of dodecylbenzene sulfonate anions could provide an enhanced selectivity to aromatic compounds such as polycyclic aromatic hydrocarbons by π–π interactions. Analysis repeatability of the new columns was satisfactory (RSD of retention time, 0.10–0.40%; RSD of peak area, 0.66–0.84%).
Optimum density of sika deer for tree seedling survival
Authors: Itô Hiroki , Hino Teruaki , Takahashi Hiroshi
Published: March 2014

Sika deer have both direct negative and indirect positive effects on tree seedlings because deer browse on seedlings themselves as well as the floor vegetation that suppresses their growth. As such, a non‐zero optimum deer density may exist for tree seedling survival. We conducted a field experiment combining exclusion of deer and removal of floor vegetation to investigate possible conditions under which an optimum density of deer with respect to seedling survival could exist. We constructed a hierarchical Bayesian model and used it to predict the survival rate of tree seedlings under different deer densities and floor leaf biomass conditions. Results indicated that a non‐zero optimum deer density existed when the following conditions were present: a negative relationship between deer density and floor leaf biomass, negative effects on seedling survival caused both by deer and by floor vegetation, positive interaction of deer and floor leaf biomass on seedling survival, and considerably large potential leaf biomass. We estimated optimum deer density was 9.5 deer/km2 when floor leaf biomass of the dwarf bamboo was 0.15 kg/m2. This optimum deer density may have been excessive because we examined only the initial stages of seedling development, in which seedlings were less vulnerable to deer browsing. These results suggested that in this system, managing deer density at moderate levels might be more effective from a forest regeneration perspective than the complete exclusion of deer. © 2014 The Wildlife Society.
Habitat use and selection of black scoters in southern New England and siting of offshore wind energy facilities
Authors: Loring Pamela H. , Paton Peter W.C. , Osenkowski Jason E. , Gilliland Scott G. , Savard Jean‐Pierre L. , Mcwilliams Scott R.
Published: March 2014

The southern New England continental shelf is an important region for black scoters (Melanitta americana) during winter and migratory staging periods and a priority area for developing offshore wind energy facilities. However, little is known about the migration phenology and habitat use of black scoters in this portion of their range and this information is necessary to assess potential risks to black scoters during the marine spatial planning process. In this regional black scoter study over 2 winters, we used satellite telemetry and spatial modeling techniques to estimate migratory timing and length of stay, quantify winter home range size and site fidelity between winters, examine key habitat characteristics associated with core‐use areas, and map relative probabilities of use across a 3,800‐km2 marine spatial planning area for 2 proposed offshore renewable energy facilities. Black scoters spent nearly 5 months in southern New England, with wide variation among individuals in the size of winter utilization distributions (range 16–12,367 km2). Approximately 50% of the tagged birds returned to southern New England during the subsequent winter and had variable fidelity to core‐use areas occupied the previous winter. During both winters, black scoter core‐use areas were located closer to shore, at shallower water depths, with coarser sediment grain size and higher probability of hard‐bottom occurrence relative to available areas. Resource selection functions classified the majority of a nearshore 5‐turbine, 34‐km2 renewable energy zone off Block Island as high probability of use by black scoters, whereas an offshore 200‐turbine, 667‐km2 federal lease block zone was classified as low to medium‐low probability of selection. Wind energy facilities, such as the Block Island site, constructed in relatively shallow (<20 m deep), nearshore habitats (<5 km) over hard‐bottomed or coarse‐sand substrate could displace some foraging black scoters wintering in this region, whereas the larger federal lease block zone located farther offshore is more likely to affect scoters dispersing among core‐use areas and during migration between wintering and breeding grounds. © 2014 The Wildlife Society.
On solitary wave solutions to the nonlinear Schrödinger equations with two parameters
Authors: Wang Fanglei , An Yukun
Published: March 2014

In this paper, we discuss the existence and multiplicity of positive solitary wave solutions for nonlinear Schrödinger equations with two parameters. The proof is based on the method of upper and lower solutions and the fixed point index.
Riemann boundary value problem for harmonic functions in Clifford analysis
Authors: Longfei Gu , Zhongxiang Zhang
Published: March 2014

In this article, we mainly deal with the boundary value problem for harmonic function with values in Clifford algebra:

urn:x-wiley:dummy:mana201100302:equation:mana201100302-math-0001where is a Liapunov surface in , the Dirac operator , are unknown functions with values in a universal Clifford algebra Under some assumptions, we show that the boundary value problem is solvable.
Numerical simulations of thermal convection under the influence of an inclined magnetic field by using solenoidal bases
Authors: Yarımpabuç D. , Tarman H.I. , Yıldırım C.
Published: March 2014

The effect of an inclined homogeneous magnetic field on thermal convection between rigid plates heated from below under the influence of gravity is numerically simulated in a computational domain with periodic horizontal extent. The numerical technique is based on solenoidal (divergence‐free) basis functions satisfying the boundary conditions for both the velocity and the induced magnetic field. Thus, the divergence‐free conditions for both velocity and magnetic field are satisfied exactly. The expansion bases for the thermal field are also constructed to satisfy the boundary conditions. The governing partial differential equations are reduced to a system of ordinary differential equations under Galerkin projection and subsequently integrated in time numerically. The projection is performed by using a dual solenoidal bases set such that the pressure term is eliminated in the process. The quasi‐steady relationship between the velocity and the induced magnetic field corresponding to the liquid metals or melts is used to generate the solenoidal bases for the magnetic field from those for the velocity field. The technique is validated in the linear case for both oblique and vertical case by reproducing the marginal stability curves for varying Chandrasekhar number. Some numerical simulations are performed for either case in the nonlinear regime for Prandtl numbers Pr = 0.05 and Pr = 0.1. Copyright © 2014 John Wiley & Sons, Ltd.
Coupled‐fed shorted strip antenna with an inductively coupled branch strip for low‐profile, small‐size LTE/WWAN tablet computer antenna
Authors: Wong Kin‐Lu , Weng Tseng‐Wei
Published: March 2014

A low‐profile, small‐size (10 × 40 mm2 on a thin dielectric substrate) planar LTE/WWAN antenna suitable for slim tablet computer application is presented. The antenna is formed by a coupled‐fed shorted strip antenna and an inductively coupled branch strip, with a chip inductor of 22 nH connected therebetween. At higher frequencies, owing to the high inductive reactance provided by the chip inductor, the branch strip will have very small effects on the antenna performances, and the coupled‐fed shorted strip antenna alone can provide a high‐band operation of 1710–2690 MHz. At lower frequencies, the embedded chip inductor can decrease the antenna's required resonant length, and the coupling feed can greatly widen the bandwidth of the excited resonant mode such that the antenna can cover a low‐band operation of 704–960 MHz. Good radiation characteristics of the antenna in the low‐band and high‐band operations are also obtained. Details of the proposed antenna and its experimental and simulated results are presented. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1041–1046, 2014
Implantable CPW‐fed rectangular patch antenna for ISM band biomedical applications
Authors: Kumar S. Ashok , Shanmuganantham T.
Published: March 2014

Implantable antennas have recently been receiving substantial attention for medical diagnosis and treatment. In this article, a coplanar waveguide‐fed monopole antenna for industrial, scientific, and medical (ISM) band biomedical applications is proposed. The antenna has a simple structure that is placed on human tissues like muscle, fat, and skin. The designed antenna is made compatible for implantation by embedding it in a FR4 substrate. The proposed antenna is simulated using the method of moment's software IE3D by assuming the predetermined dielectric constant for the human muscle tissue, fat, and skin. The antenna operates in the frequency of ISM bands, 2.4 −2.48 GHz. Simulated and measured gains attain −7.7 and −8 dBi in the frequency of 2.45 GHz. The radiation pattern, return loss, current distribution, and gain of these antennas were examined and characterized. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1060–1065, 2014
A compact planar dual band‐notched monopole antenna for UWB application
Authors: Kazim J. , Bibi A. , Rauf M. , Tariq M. , Owais
Published: March 2014

A compact UWB monopole band‐notched antenna with simple structure and small size is proposed and studied in this article. The size of the antenna is 33 × 29.6 × 1.6 mm. The proposed antenna has an impedance bandwidth (VSWR < 2) at 3.1–10 GHz, except the bandwidth at 3.3–3.7 GHz and 5.15–5.82 GHz for WLAN and WiMAX application. A notch in the ground plane is used to obtain a frequency band‐notched response at 3.3–3.7 GHz and inverted U‐shaped slot in the radiator patch is used for the rejection of frequency band 5.15–5.82 GHz. The antenna prototype is fabricated and tested, and it is observed that the measured and simulated results are in good agreement. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1095–1097, 2014
Magnetic charge, magnetic current, magnetic scalar potential, and electric vector potential
Authors: Brandão Faria Jose A.
Published: March 2014

This work presents a novel contribution to the analysis of magnetic structures, making use of several interrelated concepts such as, magnetic charge density, magnetic charge, magnetic current density, magnetic current intensity, magnetic voltage, magnetic scalar potential, and electric vector potential. These useful dual concepts arise in the analysis of Maxwell's equations when standard field sources, that is, electric charge density and electric current density are not directly at play. An application example is provided concerning the derivation of the telegrapher's equations that govern guided wave propagation in magnetic transmission lines. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1107–1111, 2014