bluuebunny/crossref_metadata_2025 huggingface dataset:
Rhenium–Germanium Triple Bonds: Syntheses and Reactions of the Germylidyne Complexes mer‐[X2(PMe3)3ReGeR] (X=Cl, I, H; R=m‐terphenyl)
Authors: Filippou Alexander C. , Chakraborty Uttam , Schnakenburg Gregor
Published: February 2013

A general approach to the first compounds that contain rhenium–germanium triple and double bonds is reported. Heating [ReCl(PMe3)5] (1) with the arylgermanium(II) chloride GeCl(C6H3‐2,6‐Trip2) (2; Trip=2,4,6‐triisopropylphenyl) results in the germylidyne complex mer‐[Cl2(PMe3)3ReGeC6H3‐2,6‐Trip2] (4) upon PMe3 elimination. An equilibrium that is dependent on the PMe3 concentration exists between complexes 1 and 4. Removal of the volatile PMe3 shifts the equilibrium towards complex 4, whereas treatment of 4 with an excess of PMe3 gives a 1:1 mixture of 1 and the PMe3 adduct of 2, GeCl(C6H3‐2,6‐Trip2)(PMe3) (2‐PMe3). Adduct 2‐PMe3 can be selectively obtained by addition of PMe3 to chlorogermylidene 2. The NMR spectroscopic data for 2‐PMe3 indicate an equilibrium between 2‐PMe3 and its dissociation products, 2 and PMe3, which is shifted far towards the adduct site at ambient temperature. NMR spectroscopic monitoring of the reaction of complex 1 with 2 and the reaction of complex 4 with PMe3 revealed the formation of two key intermediates, which were identified to be the chlorogermylidene complexes cis/trans‐[Cl(PMe3)4ReGe(Cl)C6H3‐2,6‐Trip2] (cis/trans‐3) by using NMR spectroscopy. Labile chlorogermylidene complexes cis/trans‐3 can be also generated from trans‐[Cl(PMe3)4ReGeC6H3‐2,6‐Trip2]BPh4 (9) and (nBu4N)Cl at low temperature, and decompose at ambient temperature to give a mixture of complexes 1 and 4. Complex 4 reacts with LiI to give the diiodido derivative mer‐[I2(PMe3)3ReGeC6H3‐2,6‐Trip2] (5), which undergoes a metathetical iodide/hydride exchange with Na(BEt3H) to give the dihydrido germylidyne complex mer‐[H2(PMe3)3ReGeC6H3‐2,6‐Trip2] (6). Carbonylation of 4 induces a chloride migration from rhenium to the germanium atom to afford the chlorogermylidene complex mer‐[Cl(CO)(PMe3)3ReGe(Cl)C6H3‐2,6‐Trip2] (7). Similarly, MeNC converts complex 4 into the methylisocyanide analogue mer‐[Cl(MeNC)(PMe3)3ReGe(Cl)C6H3‐2,6‐Trip2] (8). Chloride abstraction from 4 by NaBPh4 in the presence of PMe3 gives the cationic germylidyne complex trans‐[Cl(PMe3)4ReGeC6H3‐2,6‐Trip2]BPh4 (9). Heating complex 4 with cis‐[Mo(PMe3)4(N2)2] induces a germylidyne ligand transfer from rhenium to molybdenum to afford the germylidyne complex trans‐[Cl(PMe3)4MoGeC6H3‐2,6‐Trip2] (10). All new compounds were fully characterized and their molecular structures studied by X‐ray crystallography, which led to the first experimentally determined ReGe triple‐ and double‐bond lengths.
A Conductive Polypyrrole‐Coated, Sulfur–Carbon Nanotube Composite for Use in Lithium–Sulfur Batteries
Authors: Wang Jiazhao , Lu Lin , Shi Dongqi , Tandiono Richard , Wang Zhaoxiang , Konstantinov Konstantin , Liu Huakun
Published: February 2013

A novel ternary composite, polypyrrole (PPy)‐coated sulphur–carbon nanotube (S‐CNT), is synthesised by using an in situ, one‐pot method. Firstly, elemental sulfur is loaded into the CNT network by a solution‐based processing technique. Then conducting PPy is coated on the surface of the S‐CNT composite to form the S‐CNT‐PPy ternary composite by carrying out polymerization of the pyrrole monomer in situ. The ternary composite is tested as a cathode for lithium–sulfur batteries. The results show that PPy coating improves significantly the performance of the binary composites (S‐CNT and S‐PPy). The conducting PPy is believed to serve multiple functions in the composite: as a conducting additive, an active material, and an adsorbent and container to confine the polysulfides and prevent them from dissolving into the electrolyte. As a result, PPy coating on the S‐CNT composite enhances its conductivity, capacity and cycling stability. The capacity of S‐CNT‐PPy is about 600 mAh g−1 after 40 cycles, which is much higher than for the S‐CNT composite (430 mAh g−1)
Dioximate‐ and Bis(salicylaldiminate)‐Bridged Titanium and Zirconium Alkoxides: Structure Elucidation by Mass Spectrometry
Authors: Maurer Christian , Pittenauer Ernst , Puchberger Michael , Allmaier Günter , Schubert Ulrich
Published: February 2013

The treatment of titanium alkoxides with 1,5‐pentanedioxime or 2,5‐hexanedioxime resulted in the formation of complexes [{TiL(OR)2}2] in which the dioximate ligands (L) bridge a dimeric Ti2(μ2‐OR)2 unit. The structures of the complexes were determined by single‐crystal structure analysis, ESI mass spectrometry, and 1D and 2D solution NMR spectroscopy. In contrast, the treatment of titanium alkoxides with dioximes bearing cyclic linkers, such as cyclohexyl or aryl groups, resulted in insoluble polymeric compounds. The treatment of various bis(salicylaldiminates) with titanium and zirconium alkoxides resulted in compounds with the same composition [{TiL(OR)2}2], in which, however, two monomeric Ti(OR)2 units are bridged by the ligands L. The two structural possibilities can be distinguished by low‐energy collision‐induced dissociation owing to their different fragmentation patterns.
Effective application of the methanol‐based PreservCyt™ fixative and the Cellient™ automated cell block processor to diagnostic cytopathology, immunocytochemistry, and molecular biology
Authors: van Hemel Bettien M. , Suurmeijer Albert J. H.
Published: February 2013

We studied the feasibility of immunocytochemistry (ICC), in situ hybridization (ISH), and polymerase chain reaction (PCR) after Cellient™ automated cell block processing, and tested whether methanol‐based PreservCyt™ fixation could replace formalin fixation, in an attempt to eliminate toxic formaldehyde vapors. Immunostaining with 30 different antibodies was performed on cell blocks from 73 FNA specimens and 42 body cavity fluid specimens prepared by Cellient™ automated processing that uses the methanol‐based fixative (PreservCyt™). For each antibody we evaluated ICC in at least three different cell block specimens and compared it with immunohistochemistry (IHC) in formalin‐fixed, paraffin‐embedded (FFPE) histological sections from the corresponding tumors. The quality of DNA and RNA in Cellient™ blocks was analyzed by ISH, applying a SYT gene break‐apart assay and EBER probes, respectively. Moreover, DNA quality was analyzed by PCR by using primer sets for DNA products of 100, 200, 300, 400, 500, and 600 base pairs, and evaluated by gel electrophoresis. When compared with IHC results in corresponding FFPE tumor tissue from the same patient, 24 out of 30 antibodies showed concordant ICC results. With FISH, distinctive hybridization signals were observed for SYT DNA sequences and EB virus RNA sequences. With PCR, DNA products, up to 600 base pairs in size, were readily observed after gel electrophoresis. The antibodies that showed concordant immunostaining in Cellient™ blocks could be applied to diagnostic algorithms that proved to be helpful in the discrimination of major tumor types (carcinoma, lymphoma, melanoma, and germ cell tumors), discrimination of carcinoma subtypes, and determination of primary tumor site in cases of metastatic carcinoma. In a separate study, we found that the application of ICC to this cell block technique provided additional diagnostic and clinically important information in 24% of 100 consecutive cases. The high quality of DNA and RNA in Cellient™ cell blocks allowed sensitive and specific molecular biologic analysis, in particular FISH and PCR. Diagn. Cytopathol. 2013;41:734–741. © 2013 Wiley Periodicals, Inc.
Comparison of fluorescence in situ hybridization, NMP22 bladderchek, and urinary liquid‐based cytology in the detection of bladder urothelial carcinoma
Authors: Li Hong‐xia , Wang Ming‐rong , Zhao Huan , Cao Jian , Li Chang‐ling , Pan Qin‐Jing
Published: February 2013

The aim of this study is to evaluate the diagnostic values of the fluorescence in situ hybridization (FISH), NMP22 BladderChek, and liquid‐based cytology (LBC) in the detection of bladder urothelial carcinoma (UC). Consecutive voided urine samples were collected from 138 in‐house patients with a variety of urologic conditions and 37 healthy individuals as negative controls. FISH, NMP22 BladderChek, and LBC were performed on the specimens. All three tests were evaluated independently in a blinded fashion. In all, 104 out of the 175 patients enrolled in this study had histologically proven UC. LBC, FISH, and NMP22 BladderChek were successfully performed on 175, 149, and 119 cases, respectively. The three tests revealed overall sensitivities of 73.1%, 86.5%, and 67.6%, respectively. FISH was more sensitive than LBC (P=0.022) and NMP22 BladderChek (P=0.004). Combination of all the tests yielded a superior sensitivity of 96.7% compared with LBC (P<0.001), NMP22 BladderChek (P<0.001), and FISH (P=0.016), with the specificity only decreased slightly. Sensitivities of the three tests enhanced significantly with increasing UC grade (P<0.05). The positive rates of FISH and NMP22 BladderChek in equivocal cytologic diagnoses were 85.7% and 61.9% in UC, and 37.5% and 50.0% in non‐UC (FISH: P=0.021; NMP22 BladderChek: P=0.683). FISH was more sensitive than LBC and NMP22 BladderChek. FISH had the ability to clarify equivocal cytologic diagnoses. Combination of all three tests showed an improvement in the sensitivity compared to any single test alone in detecting UC with the specificity slightly decreased. Diagn. Cytopathol. 2013;41:852–857. © 2013 Wiley Periodicals, Inc.
Expression of pro‐ and anti‐angiogenic factors during the formation of the periocular vasculature and development of the avian cornea
Authors: Kwiatkowski Sam , Munjaal Ravi P. , Lee Teresa , Lwigale Peter Y.
Published: February 2013

Background: During embryonic development, endothelial precursor cells (angioblasts) migrate relatively long distances to form the primary vascular plexus. The migratory behavior of angioblasts and localization of the primitive blood vessels is tightly regulated by pro‐angiogenic and anti‐angiogenic factors encountered in the embryonic environment. Despite the importance of corneal avascularity to proper vision, it is not known when avascularity is established in the developing cornea and how pro‐ and anti‐angiogenic factors regulate this process. Results and Discussion: Using Tg(tie1:H2B:eYFP) transgenic quail embryos to visualize fluorescently labeled angioblasts, we show that the presumptive cornea remains avascular despite the invasion of cells from the periocular region where migratory angioblasts reside and form the primary vasculature. Semiquantitative reverse transcriptase polymerase chain reaction analysis and spatiotemporal examination of gene expression revealed that pro‐ and anti‐angiogenic factors were expressed in patterns indicating their potential roles in angioblast guidance. Conclusions: Our findings show for the first time that chick corneal avascularity is established and maintained during development as the periocular vasculature forms. We also identify potential candidate pro‐ and anti‐angiogenic factors that may play crucial roles during vascular patterning in the anterior eye. Developmental Dynamics 242:738–751, 2013. © 2013 by Wiley Periodicals, Inc.
Evolutionary conservation of the placodal transcriptional network during sexual and asexual development in chordates
Authors: Gasparini Fabio , Degasperi Valentina , Shimeld Sebastian M. , Burighel Paolo , Manni Lucia
Published: February 2013

Background: An important question behind vertebrate evolution is whether the cranial placodes originated de novo, or if their precursors were present in the ancestor of chordates. In this respect, tunicates are of particular interest as they are considered the closest relatives to vertebrates. They are also the only chordate group possessing species that reproduce both sexually and asexually, allowing both types of development to be studied to address whether embryonic pathways have been co‐opted during budding to build the same structures. Results: We studied the expression of members of the transcriptional network associated with vertebrate placodal formation (Six, Eya, and FoxI) in the colonial tunicate Botryllus schlosseri. During both sexual and asexual development, each transcript is expressed in branchial fissures and in two discrete regions proposed to be homologues to groups of vertebrate placodes. Discussion: Results reinforce the idea that placode origin predates the origin of vertebrates and that the molecular network involving these genes was co‐opted in the evolution of asexual reproduction. Considering that gill slit formation in deuterostomes is based on similar expression patterns, we discuss possible alternative evolutionary scenarios depicting gene co‐option as critical step in placode and pharynx evolution. Developmental Dynamics 242:752–766, 2013. © 2013 Wiley Periodicals, Inc.
Antismoking norm and smokers' antismoking attitudes: The interplay between personal and group‐based self‐esteem
Authors: Falomir‐Pichastor Juan M. , Mugny Gabriel , Berent Jacques , Pereira Andrea , Krasteva Diana
Published: February 2013

Scientific discoveries about the dangers of smoking and antismoking actions carried out in Western countries over recent decades have progressively helped create an antismoking social norm. Nevertheless, many smokers still refuse to quit. We conducted two studies to investigate smokers' resistance to this norm as a function of their personal self‐esteem (PSE) and group‐based self‐esteem (GBSE). An initial correlational study assessed smokers' perception of the antismoking social norm, their PSE, and their antismoking attitudes. Smokers with low PSE had lower antismoking attitudes than those with high PSE when the antismoking norm was strong. The second study assessed GBSE (i.e., smokers' satisfaction as smokers) and manipulated both the strength of the antismoking norm and PSE (i.e., focus on personal weaknesses or strengths). Smokers with low PSE displayed the lowest antismoking attitudes when the antismoking norm was strong and their GBSE was high. These results show that the antismoking norm can produce paradoxical effects and suggest that the way individuals cope with stigmatization is affected by the interplay between PSE and GBSE. Copyright © 2013 John Wiley & Sons, Ltd.
Voltammetric Response on a Puller‐Made Nanometer‐Sized Electrode
Authors: Li Fei , Hunt Benjamin , Sun Peng
Published: February 2013

The method of fabrication of electrodes by using a laser‐puller is a commonly used method to produce small electrodes. Simulation shows that the taper‐shaped insulation layer of a puller‐made electrode has an obvious effect on its voltammetric response, especially when the electrode has a small RG (the ratio of the insulating sheath radius to the electrode radius). The effect of low‐pass filtering on the voltammetric response of a very small puller‐made electrode has also been studied.
Determination of kinetic parameters of biomass samples using thermogravimetric analysis
Authors: Parthasarathy Prakash , Narayanan Sheeba K.
Published: February 2013

In this work, thermogravimetric analysis is carried out on four different biomass samples such as bagasse, coir–pith, groundnut shell and casuarina leaves to study their thermal behaviour. Analysis is put through in an inert nitrogen atmosphere from ambient temperature to 800°C at a heating rate of 10°C/min. Three reaction zones corresponding to dehydration, hemicellulose–cellulose degradation and lignin degradation are observed for all four biomass samples. The kinetic parameters such as activation energy, pre–exponential factor and order of the reaction for all the components of samples are determined using the simple Arrhenius equation. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 256–266, 2014
Amounts, isotopic character, and ages of organic and inorganic carbon exported from rivers to ocean margins: 1. Estimates of terrestrial losses and inputs to the Middle Atlantic Bight
Authors: Hossler Katie , Bauer James E.
Published: February 2013

Rivers transport carbon (C) from terrestrial ecosystems to the coastal ocean, providing significant heterotrophic support within both rivers and receiving coastal waters. The amounts and ages of these terrestrial‐river‐coastal ocean C fluxes, however, are still poorly constrained. To address this uncertainty, a study of eight rivers discharging to the Middle Atlantic Bight (MAB) was undertaken. The rivers were sampled periodically over 2 years for concentrations and δ13C and Δ14C signatures of particulate organic C (POC), dissolved organic C (DOC), and dissolved inorganic C (DIC). For the watersheds draining to the MAB, it was estimated that ∼3800 Gg of terrestrial organic C (OC) and 700 Gg of terrestrial inorganic C was removed annually by fluvial transport. Of the terrestrial OC loss, ∼64% was contemporary C representing approximately 1% of the annual terrestrial net primary productivity. Net fluvial C inputs to the MAB shelf were estimated to be ∼70 Gg·yr − 1 of POC, 280 Gg·yr − 1 of DOC, and 800 Gg·yr − 1 of DIC. Terrestrial C, as opposed to in situ produced river C, comprised the majority of the riverine POC and DOC flux and around half of the total C flux. A smaller but significant fraction (<25%) of the river C flux was further composed of aged materials deriving from fossil C and aged soil OC. The timing of fluvial OC inputs to the MAB, which appear to be temporally offset from peak MAB primary production, could help support the net heterotrophy that has been observed there during periods of low productivity.
Effects of permeability fields on fluid, heat, and oxygen isotope transport in extensional detachment systems
Authors: Gottardi Raphaël , Kao Po‐Hao , Saar Martin O. , Teyssier Christian
Published: February 2013

Field studies of Cordilleran metamorphic core complexes indicate that meteoric fluids permeated the upper crust down to the detachment shear zone and interacted with highly deformed and recrystallized (mylonitic) rocks. The presence of fluids in the brittle/ductile transition zone is recorded in the oxygen and hydrogen stable isotope compositions of the mylonites and may play an important role in the thermomechanical evolution of the detachment shear zone. Geochemical data show that fluid flow in the brittle upper crust is primarily controlled by the large‐scale fault‐zone architecture. We conduct continuum‐scale (i.e., large‐scale, partial bounce‐back) lattice‐Boltzman fluid, heat, and oxygen isotope transport simulations of an idealized cross section of a metamorphic core complex. The simulations investigate the effects of crust and fault permeability fields as well as buoyancy‐driven flow on two‐way coupled fluid and heat transfer and resultant exchange of oxygen isotopes between meteoric fluid and rock. Results show that fluid migration to middle to lower crustal levels is fault controlled and depends primarily on the permeability contrast between the fault zone and the crustal rocks. High fault/crust permeability ratios lead to channelized flow in the fault and shear zones, while lower ratios allow leakage of the fluids from the fault into the crust. Buoyancy affects mainly flow patterns (more upward directed) and, to a lesser extent, temperature distributions (disturbance of the geothermal field by ~25°C). Channelized fluid flow in the shear zone leads to strong vertical and horizontal thermal gradients, comparable to field observations. The oxygen isotope results showδ18O depletion concentrated along the fault and shear zones, similar to field data.
Desmosterol in Human Nonalcoholic Steatohepatitis
Authors: Simonen Marko , Männistö Ville , Leppänen Joel , Kaminska Dorota , Kärjä Vesa , Venesmaa Sari , Käkelä Pirjo , Kuusisto Johanna , Gylling Helena , Laakso Markku , Pihlajamäki Jussi
Published: February 2013

Dysregulation of the cholesterol synthesis pathway and accumulation of cholesterol in the liver are linked to the pathogenesis of nonalcoholic steatohepatitis (NASH). Therefore, we investigated the association of serum and liver levels of cholesterol precursors with NASH. Liver histology was assessed in 110 obese patients (Kuopio Obesity Surgery Study [KOBS] study, age 43.7 ± 8.1 years [mean ± standard deviation, SD], body mass index [BMI] 45.0 ± 6.1 kg/m2). Serum and liver levels of cholesterol precursors were measured with gas-liquid chromatography. The association between cholesterol precursors and serum alanine aminotransferase (ALT), as a marker of liver disease, was also investigated in a population cohort of 717 men (Metabolic Syndrome in Men Study [METSIM] study, age 57.6 ± 5.8 years, BMI 27.1 ± 4.0 kg/m2). Serum desmosterol levels and the desmosterol-to-cholesterol ratio were higher in individuals with NASH, but not in individuals with simple steatosis, compared to obese subjects with normal liver histology (P = 0.002 and P = 0.003, respectively). Levels of serum and liver desmosterol correlated strongly (r = 0.667, P = 1 × 10−9), suggesting a shared regulation. Both serum and liver desmosterol levels correlated positively with steatosis and inflammation in the liver (P < 0.05). Serum desmosterol had a higher correlation with the accumulation of cholesterol in the liver than serum cholesterol. Serum desmosterol levels (P = 2 × 10−6) and the serum desmosterol-to-cholesterol ratio (P = 5 × 10−5) were associated with serum ALT in the population study. Conclusion: Levels of desmosterol in serum and the liver were associated with NASH. These results suggest that serum desmosterol is a marker of disturbed cholesterol metabolism in the liver. Whether desmosterol has a more specific role in the pathophysiology of NASH compared to other cholesterol precursors needs to be investigated. (Hepatology 2013;53:976–982)
Liver stiffness is influenced by a standardized meal in patients with chronic hepatitis C virus at different stages of fibrotic evolution
Authors: Arena Umberto , Platon Monica Lupsor , Stasi Cristina , Moscarella Stefania , Assarat Alì , Bedogni Giorgio , Piazzolla Valeria , Badea Radu , Laffi Giacomo , Marra Fabio , Mangia Alessandra , Pinzani Massimo
Published: February 2013

Transient elastography (TE) is increasingly employed in clinical practice for the noninvasive detection of tissue fibrosis in patients with chronic liver disease (CLD), and particularly chronic hepatitis C virus (HCV)-related hepatitis. The present study was designed to provide a definitive characterization of the “confounding” increase in liver stiffness (LS) following a standardized meal in a consecutive population of 125 patients with chronic HCV infection at different stages of fibrotic evolution. LS values were obtained after overnight fasting and 15, 30, 45, 60, and 120 minutes following the onset of a standardized liquid meal (400 mL, 600 Kcal, 16.7% protein, 53.8% carbohydrates, 29.5% fat). An evident increase in LS values was observed 15 to 45 minutes after the onset of the meal with return to baseline premeal levels within 120 minutes in all patients. The peak postmeal delta increase in LS was progressively more marked with increasing stages of fibrosis (P < 0.001), becoming maximal in patients with cirrhosis. However, the probability of identifying the Metavir stage of fibrosis, the Child-Pugh class, or the presence/absence of esophageal varices with the postmeal delta increase in LS was inferior to that obtained with baseline LS values. Conclusion: The results of the present study provide definitive evidence of the confounding effect of a meal on the accuracy of LS measurements for the prediction of fibrosis stage in patients with chronic HCV hepatitis and suggest that a fasting period of 120 minutes should be observed before the performance of TE. (HEPATOLOGY 2013;)
Influence of local objects on hippocampal representations: Landmark vectors and memory
Authors: Deshmukh Sachin S. , Knierim James J.
Published: February 2013

The hippocampus is thought to represent nonspatial information in the context of spatial information. An animal can derive both spatial information as well as nonspatial information from the objects (landmarks) it encounters as it moves around in an environment. In this article, correlates of both object‐derived spatial as well as nonspatial information in the hippocampus of rats foraging in the presence of objects are demonstrated. A new form of CA1 place cells, called landmark‐vector cells, that encode spatial locations as a vector relationship to local landmarks is described. Such landmark vector relationships can be dynamically encoded. Of the 26 CA1 neurons that developed new fields in the course of a day's recording sessions, in eight cases, the new fields were located at a similar distance and direction from a landmark as the initial field was located relative to a different landmark. In addition, object‐location memory in the hippocampus is also described. When objects were removed from an environment or moved to new locations, a small number of neurons in CA1 and CA3 increased firing at the locations where the objects used to be. In some neurons, this increase occurred only in one location, indicating object + place conjunctive memory; in other neurons, the increase in firing was seen at multiple locations where an object used to be. Taken together, these results demonstrate that the spatially restricted firing of hippocampal neurons encode multiple types of information regarding the relationship between an animal's location and the location of objects in its environment. © 2013 Wiley Periodicals, Inc.
Role of Cytochrome P4502B6 in Methadone Metabolism and Clearance
Authors: Kharasch Evan D. , Stubbert Kristi
Published: February 2013

Methadone N‐demethylation in vitro is catalyzed by hepatic cytochrome P4502B6 (CYP2B6) and CYP3A4, but clinical disposition is often attributed to CYP3A4. This investigation tested the hypothesis that CYP2B6 is a prominent CYP isoform responsible for clinical methadone N‐demethylation and clearance, using the in vivo mechanism‐based CYP2B6 inhibitor ticlopidine, given orally for 4 days. A preliminary clinical investigation with the CYP3A4/5 substrate probe alfentanil established that ticlopidine did not inhibit intestinal or hepatic CYP3A4/5. Subjects received intravenous plus oral (deuterium‐labeled) racemic methadone before and after ticlopidine. Ticlopidine significantly and stereoselectively (S > R) inhibited methadone N‐demethylation, decreasing plasma metabolite/methadone area under the curve ratios and metabolite formation clearances. Ticlopidine also significantly increased the dose‐adjusted plasma area under the curve for R‐ and S‐methadone by 20% and 60%, respectively, after both intravenous and oral dosing. CYP2B6 inhibition reduces methadone N‐demethylation and clearance, and alters methadone concentrations, demonstrating an important role for CYP2B6 in clinical methadone disposition.
Detection of multiple viral and bacterial infections in acute exacerbation of chronic obstructive pulmonary disease: A pilot prospective study
Authors: Perotin Jeanne‐Marie , Dury Sandra , Renois Fanny , Deslee Gaëtan , Wolak Aurore , Duval Véronique , De Champs Christophe , Lebargy François , Andreoletti Laurent
Published: February 2013

Few studies have evaluated the contribution of multiple virus and bacterial infections in acute exacerbation of chronic obstructive pulmonary disease. This study estimated the burden of multiple viral and bacterial respiratory infections in moderate to very severe chronic obstructive pulmonary disease patients that were prospectively followed‐up during a 12‐month pilot study. Clinical data were collected monthly and sputum was collected at the time of each acute exacerbation event. Classical culture techniques for bacteria and multiplex polymerase chain reaction (PCR) and microarray detection assays were performed to identify viral and atypical bacterial pathogens in the sputum. Overall, 51 patients were included and 45 acute exacerbation events were investigated clinically and microbiologically. Among the 45 acute exacerbation events, 44% had evidence of viral infection involving human rhinovirus (HRV) and metapneumovirus (hMPV) in 20% and 18%, respectively. Intracellular bacteria were not found in sputum by PCR. Common bacterial pathogens were identified in 42% of acute exacerbation patients, most frequently Branhamella catarrhalis, Streptococcus pneumoniae and Haemophilus influenzae. Viral or virus and bacteria co‐infections were detected in 27% of acute exacerbation events (n = 12) with HRV and hMPV involved in 92% of cases. Patients with co‐infections did not present greater clinical severity scores at exacerbation and more recurrence of acute exacerbation events at 3 and 6 months than those with single infections (P > 0.4). These results suggest that HRV and hMPV may be contributors or cofactors of AECOPD. These findings indicate that viral or virus and bacterial co‐infections do not impact significantly on the clinical severity of acute exacerbation of chronic obstructive pulmonary disease and recurrence at 3 and 6 months. J. Med. Virol. 85:866–873, 2013. © 2013 Wiley Periodicals, Inc.
A detailed rainfall climatology for Malawi, Southern Africa
Authors: Nicholson S. E. , Klotter D. , Chavula G.
Published: February 2013

ABSTRACT

This article presents a detailed analysis of the mean rainfall climatology of Malawi and an overview of interannual variability. Monthly and seasonal means, the seasonal cycle and intraseasonal variability are examined. This includes an analysis of the onset, end and duration of the rainy season. The study reveals two surprising features of the rainfall regime. One is a region with a strong rainfall maximum in the austral autumn along the western shore of Lake Malawi. The second is a brief period of reduced rainfall in mid‐February that appears to signal a shift in the prevailing rainfall and circulation regime. The prevailing atmospheric circulation is markedly different before and after the break, as are the characteristics of the rainy season. Overall, the results indicate that the early (pre‐break) rainy season (December–February) is dominated by tropical influences, the late (post‐break) rainy season (March–April) is dominated by extra‐tropical influences and interannual variability in these two periods is uncorrelated. The results also demonstrate two aspects of interannual variability: the dominant contribution of the MA season and the frequent opposition between northern and southern Malawi.
Do You Have the Guts to Grow During Tough Times?
Authors: Recardo Ronald J. , Toterhi Tim
Published: February 2013

Today's business leaders face ever‐increasing global competition and a more robust regulatory environment than ever, and they are doing so in the midst of the most profound financial and economic dislocation of the past 100 years. Too many of them, however, seem to flinch in the face of these challenges by trying to extricate their organizations from the jaws of the Second Great Depression through blanket cost‐cutting measures. Although thoughtful resource allocation is certainly an effective stabilizing force, organizational leaders that seek to expand their businesses must have the courage to reach beyond myopic measures and employ a targeted strategy that leverages the appropriate elements of both internal and external growth engines to increase the top line as well as the bottom line. © 2013 Wiley Periodicals, Inc.
Liver transplantation for children with biliary atresia in the pediatric end-stage liver disease era
Authors: Arnon Ronen , Annunziato Rachel A. , Willis Asha , Parbhakar Meera , Chu Jaime , Kerkar Nanda , Shneider Benjamin L.
Published: February 2013

Socioeconomic status influences health outcomes, although its impact on liver transplantation (LT) in children with biliary atresia (BA) is unknown. We hypothesized that governmental insurance [public insurance (PU)], rather than private insurance (PR), would be associated with poorer outcomes for children with BA. Children with BA who underwent first isolated LT between January 2003 and June 2011 were identified from United Network for Organ Sharing Standard Transplant Analysis and Research files. We identified 757 patients with PR and 761 patients with PU. The race/ethnicity distribution was significantly different between the groups (65% white, 12% black, and 10% Hispanic in the PR group and 33% white, 26% black, and 29% Hispanic in the PU group, P < 0.01). Wait-list mortality was higher for the PU group versus the PR group [46/1654 (2.7%) versus 29/1895 (1.5%), P < 0.01]. PR patients were older than PU patients at transplant (2.4 ± 4.5 versus 1.5 ± 3.0 years, P < 0.01). The donor types differed between the groups: 165 children (21.8%) in the PR group received living donor grafts, whereas 79 children (10.4%) in the PU group did (P < 0.01). The 1- and 5-year posttransplant patient survival rates were greater for the PR group versus the PU group (98.0% versus 94.1% at 1 year, P < 0.01; 97.8% versus 92.2% at 5 years, P < 0.01). Cox proportional hazards models revealed that the insurance type (PU), the donor type (deceased), and life support were significant risk factors for death. A separate analysis of deceased donor LT revealed that the PU group still had significantly worse patient and graft survival. In conclusion, PU coverage is an independent risk factor for significantly increased wait-list and posttransplant mortality in children with BA. Further studies are needed to unearth the reasons for these important differences in outcomes. Liver Transpl 19:543–550, 2013. © 2013 AASLD.
Left hepatectomy versus right hepatectomy for living donor liver transplantation
Authors: Roll Garrett R. , Parekh Justin R. , Parker William F. , Siegler Mark , Pomfret Elizabeth A. , Ascher Nancy L. , Roberts John Paul
Published: February 2013

Living donor liver transplantation (LDLT), originally used in children with left lateral segment grafts, has been expanded to adults who require larger grafts to support liver function. Most adult LDLT procedures have been performed with right lobe grafts, and this means a significant risk of morbidity for the donors. To minimize the donor risk for adults, there is renewed interest in smaller left lobe grafts. The smaller graft size increases the recipient risk in the form of small-for-size syndrome (SFSS) and essentially transfers the risk from the donor to the recipient. We review the donor and recipient risks of LDLT and pay particular attention to the different types of liver grafts and the use of graft inflow modification to ameliorate the risk of SFSS. Finally, a new metric is proposed for quantifying the recipient benefit in exchange for a specific donor risk. Liver Transpl 19:472–481, 2013. © 2013 AASLD.
Exploratory use of a satellite cloud mask to verify NWP models
Authors: Crocker Ric , Mittermaier Marion
Published: February 2013

Surface observations of cloud cover for routine verification typically come from manual observations (a human observer makes a visual inspection of the observable sky) or from automated instruments (taking a time‐averaged sample of the cloud passing directly overhead). Each observation type has associated limitations. Here a cloud mask field derived from satellite data is examined as an observation type, providing a top‐down view of cloud cover. This paper shows that the satellite cloud mask field can be used to assess details of spatial bias differences between regional numerical weather prediction (NWP) models over the United Kingdom (UK). The Structure‐Amplitude‐Location (SAL) method is used to show how the distribution of cloud within the NWP model domain can be assessed. Finally the satellite cloud mask is used to derive single site observations which can be used to complement the existing surface observation network, or provide total cloud amount guidance in data sparse locations and shows how it could potentially be used to condition surface observational data in the presence of cirrus. © 2013 British Crown copyright, the Met Office. Published by John Wiley & Sons Ltd.
The Robin problem for the scalar Oseen equation
Authors: Medková Dagmar , Skopin Emma , Varnhorn Werner
Published: February 2013

We study the Robin problem for the scalar Oseen equation in an open n‐dimensional set with compact Ljapunov boundary. We prescribe two types of Robin boundary conditions, and prove the unique solvability of these problems as well as a representation formula for the solution in form of a scalar Oseen single layer potential. Moreover, we prove the maximum principle for the solution to the Robin problem of the scalar Oseen equation. Copyright © 2013 John Wiley & Sons, Ltd.
Modulation accuracy of binary phase‐shift keying signal broadcast after injection locking of a resonant tunneling diode microwave oscillator
Authors: Cantú Horacio I. , Romeira Bruno , Figueiredo Jose M. L. , Kelly Anthony E. , Ironside Charles N.
Published: February 2013

Injection of a binary phase‐shift keyed signal to a resonant tunneling diode (RTD)‐based microwave oscillator is presented in this article. The locked signal is broadcast through a wireless communications link and also converted from optical to radio frequency domain using a RTD photodetector. Modulation accuracy is evaluated through error vector magnitude and bit error rate using computer software routines. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:705–711, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27403
Compact h‐ring antenna with dual‐band operation for wireless sensors and RFID tag systems in ISM frequency bands
Authors: Ojaroudi Nasser , Ojaroudi Mohammad
Published: February 2013

A novel design of dual‐band microstrip‐fed monopole antenna for radio frequency identification (RFID) applications is presented in this article.The proposed antenna is designed to operate at 2.45 GHz, 5.8 GHz (ISM bands), and it is fabricated on the FR4 substrate with dielectric constant of 4.4. By using H‐shaped antenna, we can gave a new resonance at lower frequencies (2.45 GHz), also by embedding H‐shaped slot, the proposed antenna with H‐ring structure can be created and achieves good dual‐band operation. The measured impedance bandwidth for −l0 dB return loss is from 2.05 to 2.83 GHz (33%) and 5.30 to 6.32 GHz (15.0%), covering the 2.4/5.8 GHz RFID operating bands. Simulated and experimental results obtained for this antenna show that the proposed H‐ring monopole antenna has a good antenna gains and radiation behavior within the 2.4/5.8 GHz frequencies. The designed antenna has a small size of 12 × 18 mm2. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:697–700, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27404
Enhanced H‐field in HF RFID systems by optimizing the loop spacing of antenna coils
Authors: Sharma Ashwani , Zuazola Iñaki J.Garcia , Gupta Anshu , Perallos Asier , Batchelor John C.
Published: February 2013

This article presents a design study of a coil antenna with enhanced magnetic field (H‐field), aimed to be used as an interrogator in high frequency radio frequency identification. To achieve this, the number of loops of the antenna are refined by optimizing and exploiting the inner area of an initial coil, using distributed loops, unconstrained inductance and comparable Q‐factor (for a fair comparison) with respect to an initial design. The analytical and simulated results show reasonable agreement to validate the design. The enhanced H‐ field of the antenna shows an unconstrained Q‐factor, indicates a potential rise to the interrogating coverage and hence, resulting in more efficient antenna. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:944–948, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27406
Fault analysis: Optical performance investigation of fiber connections using incorrectly cleaved fiber ends
Authors: Kihara Mitsuru , Yajima Yuichi , Watanabe Hiroshi , Toyonaga Masanobu
Published: February 2013

Incorrectly cleaved fiber ends, which are not ideal and are uneven, result from the use of a defective fiber cleaver. The optical performance of field installable connections using incorrectly cleaved fiber ends might deteriorate to more than 40 dB for insertion loss and less than 30 dB for return loss. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:941–944, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27407
Analysis of crosstalk between 10 Gb/s x 64 channels in two‐pump fiber optical parametric amplifier
Authors: Callegari Fulvio A. , Marconi Jorge D. , Fragnito Hugo L.
Published: February 2013

We present a numerical study of 64 signals amplified by a two‐pump fiber optical parametric amplifier. The amplifier was alternatively simulated with two fibers with different values of nonlinear coefficient but the same length. The gain remained constant in both cases. The performance of the amplifier is improved when it is designed with the fiber of lower nonlinear coefficient. Also, it was observed that the performance of the amplifier is strongly dependent on channel separation. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:926–929, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27408
Miniaturized dual‐band antenna for wireless local area network
Authors: Lee Jaesuk , Liu Yang , Kim Hyeongdong
Published: February 2013

In this article, size reduction and wide impedance feeding techniques for antenna design are presented.An inductor connected with a main antenna element in series reduced a resonance frequency of the fundamental mode and a size reduction of about 33% was obtained. In addition, a shunt capacitor between the shorting and feed line enhanced the impedance bandwidth to fully cover the required impedance bandwidths of IEEE 802.11 b/g (2.4–2.484 GHz) and IEEE 802.11a (5.15–5.875 GHz) The proposed antenna possesses a very wide impedance bandwidth of 1957 MHz in the range of the 5 GHz band at a VSWR < 2. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:850–852, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27411
Smart receiver system of green hybrid antennas
Authors: Jamlos M.F. , Kamarudin M.R. , Malek M.F. , Jusoh M. , Jamlos M.A.
Published: February 2013

A hybrid of multiformities receiver system is proposed in this article.The system is developed through a combination of reconfigurable beam‐steering antenna, reconfigurable beam‐shaping antenna, and data acquisition (DAQ) boards. The combination of beam‐steering antenna with beam‐shaping antenna formed a hybrid four‐layer structure with fabricated element plank of rice husk placed between the beam‐shaping antenna's feed line and beam‐steering antenna's radiating element. This four‐layer hybrid and element plank are held together by 5 mm PCB supports at every edge of the antennas forming a stack configuration. The PIN diode switches of both antennas are connected with DAQs to adaptively control the degree angle and beamwidth of the radiation patterns. The activation of either beam‐steering antenna or beam‐shaping antenna depends on the DAQs' Beam Manager memory and the weakest level of received signal strength. When the transmitted signal is coming from the angle of 0°/360°, 90°, 180°, and 270°, its range and angles' location will automatically be detected by the first DAQ that is connected to the beam‐steering antenna. Meanwhile, the beam‐shaping antennas are activated by the second DAQ, to receive the transmitted signal for a longer range at four different gains: 3.6 dB, 7.2 dB, 9.9 dB, and 14.64 dB. Hence, this hybrid receiver system collectively contributes to the well‐developed eight‐multiformity radiation patterns that can be inter‐changed within only 0.01 ms. Furthermore, signal reliability is paramount since the system could self‐elucidate the mutual coupling effects with the aid of rice husk element plank, which acts as a RF absorber. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:800–809, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27412
Compact wideband bandpass filter using two open loop resonators
Authors: Ma Xing‐Bing , Zheng Hong‐Xing
Published: February 2013

In order to obtain a wideband passband filter, a compact filter with two open‐loop resonators has been designed and fabricated, which has introduced two transmission zeros at the passband's upper frequency area.The proposed topology is demonstrated with a design operating at 5.19 GHz with 19.7% bandwidth. More than 20 dB of spurious suppression from 0 to 3.69 and from 6.27 to 9.71 GHz is demonstrated in the experimental results. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:915–917, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27415
Orthogonal slit cut stacked circular patch microstrip antenna for multiband operations
Authors: Gupta Surendra K. , Sharma Ashish , Kanaujia Binod K. , Rudra Shekhar , Mishra Ritu Raj , Pandey G.P.
Published: February 2013

In this paper, a novel orthogonal slit cut stacked circular patch antenna (SC‐SCPA) is proposed for multi band operations. The antenna structure is investigated by cutting two pair of orthogonal slits on the upper patch whose effects are studied in terms of the return loss, input impedance, gain, directivity, and radiation pattern. Multiple resonances are observed that too at lower frequency signifying the compactness and multiband nature of the proposed antenna. The antenna is resonating at four operating frequencies 7.4, 9.0, 9.4, and 10.8 GHz, and 27% reduction in size is achieved by slit cut stacked patch antenna. The proposed theory which is verified by simulation and theoretical results is in good agreement with the simulated results obtained by Ansoft's HFSS. The antenna is working in X‐band from 7 to 12 GHz and applications pertaining to this regime are also discussed herein. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:873–882, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27416
Novel hybrid four‐mode microstrip bandpass filter using two paralleled stub‐loaded resonators
Authors: Guan Xuehui , Wang Xiaoyan , Wang Bin , Yuan Ye , Liu Haiwen
Published: February 2013

A novel hybrid four‐mode microstrip bandpass filter (BPF) is proposed in this paper.The filter is realized by association of two stub‐loaded dual‐mode resonators. Two similar stub‐loaded dual‐mode resonators are set in parallel. By appropriately arranging the two dual‐mode resonators and the coupling between resonators with the microstrip feed lines, a new hybrid four‐mode BPF is achieved. The even‐ and odd‐mode theory is introduced to minutely analyze dual‐mode resonators. Moreover the circuit model and coupling matrix of the filter are built to further explain the proposed circuit. The proposed BPF is simulated, fabricated, and measured. Two transmission zeros have been achieved in the transition band of the filter, which improve the performance of the filter. The EM simulated and measured results are presented and excellent agreement is obtained validates the design concept. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:840–845, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27418
Broadband left‐handed rectangular waveguide using a shorted stub and twisted E‐plane posts
Authors: Kim Dong‐Jin , Lee Jeong‐Hae
Published: February 2013

A broadband left‐handed (LH) waveguide operating above the cutoff frequency is presented. The unit cell consists of one‐shorted stub and two‐twisted posts. The structure induces double loops in the surface currents, resulting in enhanced inductance which broadens the negative permeability region. To analyze the LH properties of the structure, a 2‐port network cross‐connected equivalent circuit is derived. The measured results of the LH waveguide constructed with five unit cells in an X‐band are in good agreement with simulated data and show a good transmission property as well as a broad LH fractional bandwidth of 26.5%. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:835–840, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27419