bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adipokines, an adipose tissue and placental product with biological functions during pregnancy
Authors: D'Ippolito Silvia , Tersigni Chiara , Scambia Giovanni , Di Simone Nicoletta 
Published: January 2012

AbstractLatter half of pregnancy is characterized by a “physiological diabetogenic state” since changes in insulin‐sensitivity have been well documented. These changes ensure continuous supply of nutrients to the growing fetus. In the last years the role of adipocyte‐derived signaling molecules, collectively known as adipokines has been object of different in vitro and in vivo studies. Of interest, adipokines and/or their receptors are expressed in the placental tissue which, therefore, can contribute to development of maternal insulin‐resistance and, as a consequence, fetal growth. Leptin, adiponectin, and resistin represent the most well studied adipokines and, with the exception of adiponectin, their serum and placental levels increase as pregnancy progresses. High levels of adipokines have also been detected in umbilical plasma hence suggesting a possible role on fetal development and metabolism; however, it remains still unclear if such adipokines can directly stimulate fetal tissues development acting as growth factors. In addition to their well known metabolic effects, we also reported studies describing the role of adipokines in promoting proliferation and invasiveness of trophoblast cells and affecting local angiogenic processes. These observations strongly suggest that adipokines, by alternatively interfering with placental development, may affect pregnancy outcome and fetal growth. However, further studies are needed to better understand the local regulation of their expression. © 2012 International Union of Biochemistry and Molecular Biology, Inc.
Reoperative surgery for bilateral multinodular goitre in the era of total thyroidectomy
Authors: Vasica G , O'Neill C J , Sidhu S B , Sywak M S , Reeve T S , Delbridge L W 
Published: January 2012

Abstract

Background
Total thyroidectomy, rather than bilateral subtotal thyroidectomy, is now accepted as the preferred management for bilateral benign multinodular goitre (BMNG) in order to reduce the need for reoperative surgery. The aim of this study was to examine whether this approach has had an impact on presentation for bilateral reoperative thyroid surgery.

Methods
This was a retrospective cohort study. The study group comprised patients presenting with recurrent BMNG who underwent bilateral reoperative thyroid surgery following previous bilateral subtotal or partial thyroidectomy. They were compared with patients undergoing unilateral reoperative thyroid surgery following previous lobectomy, and those undergoing primary total thyroidectomy for BMNG.

Results
Between 1 January 1987 and 31 December 2009, 12 354 consecutive thyroid procedures were undertaken. Among those with BMNG, primary total thyroidectomy was undertaken in 3298 patients, unilateral reoperative thyroidectomy in 337 and bilateral reoperative thyroidectomy in 191. Presentations of patients with recurrent BMNG declined gradually over the study period following the change in policy from subtotal to total thyroidectomy; only five patients (representing less than 0·5 per cent of all thyroid surgery) underwent bilateral reoperative surgery for BMNG in the last year of the study. Four of these patients had their initial operation before 1987 and in another unit, whereas the remaining patient initially had surgery overseas.

Conclusion
The introduction of a policy of initial total thyroidectomy for bilateral BMNG has essentially eliminated the need for bilateral reoperative surgery for recurrent goitre.
Characterization of secondary volatile profiles in Nigella sativa seeds from two different origins using accelerated solvent extraction and gas chromatography‐mass spectrometry
Authors: Liu Xue , Abd El‐Aty A. M. , Cho S.‐K. , Yang Angel , Park Jong‐Hyouk , Shim Jae‐Han 
Published: January 2012

ABSTRACTThe extraction and identification of bioactive compounds from herbs is of great interest. In this study, accelerated solvent extraction (ASE) technique was used to analyze the secondary volatile profiles in Nigella sativa seeds obtained from two different origins, Egypt and Bangladesh. The main extraction parameters, including extraction temperature, pressure and static extraction time, were investigated and optimized. Identification and quantification of the major constituents in nonpolar extracts (hexane) were achieved by means of GC‐FID/GC‐MS analysis with external standards. The two seeds showed a similar variety of chemical composition; however, the secondary volatiles profile of Bangladesh seed was higher than that of the Egyptian seed. A total of 25 compounds were identified from the ASE extract under the following optimum extraction conditions: 100°C, 1500 psi and 5 min, for extraction temperature, pressure and static time, respectively. The proposed technique can be used for the characterization of N. sativa varieties or cultivars. Copyright © 2012 John Wiley & Sons, Ltd.
Kinetics of CO2 Absorption by a Blended Aqueous Amine Solution
Authors: Ume C. S. , Ozturk M. C. , Alper E. 
Published: January 2012

AbstractThe reaction rates of CO2 in an aqueous blend of amine solutions of N‐(2‐hydroxethyl)piperazine (N‐HEPZ) and 2‐amino‐2‐hydroxymethyl‐1,3‐propanediol (AHPD) at 298 K were investigated in a concentration range of 0.0025–0.03 kmol m–3 N‐HEPZ with a blend of 1 kmol m–3 AHPD. The reaction was modeled using a termolecular reaction mechanism with a rate of 12 971 m3kmol–1s–1. The results indicate that the blended aqueous solution of N‐HEPZ and AHPD is a potential candidate as an alternative solvent for CO2 absorption, where the sterically hindered AHPD increases the CO2 capacity and the reaction rate is enhanced by the promoter, N‐HEPZ.
Carbon Dioxide Capture from Power Generation – Status of Cost and Performance
Authors: Finkenrath M. 
Published: January 2012

AbstractEnergy scenarios suggest that CO2 capture and storage (CCS) from power plants might contribute significantly to global greenhouse gas emission reduction. Since CCS from power generation is an emerging technology that has not been demonstrated on a commercial scale, related cost and performance information is still uncertain. This paper presents a detailed analysis of the impact of adding CO2 capture and compression process equipment to fossil‐fuelled power plants. For coal‐fired power generation, no single capture technology outperforms available alternative capture processes in terms of cost and performance.
Examination of the influence of different variables on prediction of unit cell parameters in perovskites using counter‐propagation artificial neural networks
Authors: Kuzmanovski Igor , Dimitrovska‐Lazova Sandra , Aleksovska Slobotka 
Published: January 2012

In this work, the unit cell parameter (a) of the series of cubic ABX3 perovskites was modeled using counter‐propagation artificial neural networks, and the influence of different input variables was examined by using algorithm for automatic adjustment of the relative importance of the variables. The input variables used in this model were the ionic radii of A, B, and X as well as the oxidation state (z) and the electronegativity (χ) of the anion.The developed models have good generalization performances—good agreement between experimental and predicted values for lattice parameter. One of the important outcomes from this work is obtained from the results of the automatic adjustment of the relative importance of input variables. That is to say, this analysis gave us an insight that the most pronounced influence on the successful prediction of the unit cell parameter of the analyzed data set of cubic ABX3 perovskites has the effective ionic radii of B‐cation. In addition to this, it may be concluded that the separation of the compounds in different regions of counter‐propagation artificial neural networks was predominantly influenced by the input variables with regard to the physical parameters of the anion. Copyright © 2012 John Wiley & Sons, Ltd.
Switchable Self‐Assembly of a Bioinspired Alkyl Catechol at a Solid/Liquid Interface: Competitive Interfacial, Noncovalent, and Solvent Interactions
Authors: Saiz‐Poseu Javier , Faraudo Jordi , Figueras Antoni , Alibes Ramon , Busqué Felix , Ruiz‐Molina Daniel 
Published: January 2012

AbstractThe large tendency of catechol rings to adsorb on surfaces has been studied by STM experiments with molecular resolution combined with molecular‐dynamics simulations. The strong adhesion is due to interactions with the surface and solvent effects. Moreover, the thermodynamic control over the differential adsorption of 1 and the nonanoic solvent molecules has been used to induce a new temperature‐induced switchable interconversion. Two different phases that differ in their crystal packing and the presence of solvent molecules coexist upon an increase or decrease in the temperature. These results open new insight into the behavior of catechol molecules on surfaces and 2D molecular suprastructures.
Practical exercises for learning to construct NMR/MRI probe circuits
Authors: Wheeler Dustin D. , Conradi Mark S. 
Published: January 2012

AbstractNine sets of laboratory exercises are designed to acquaint the student with many aspects of NMR/MRI probe resonant circuits. These include demonstrations of stray inductance and capacitance, matching a resonant circuit to 50 Ω, inductive coupling, doubly resonant circuits, loading effects of tissue, and radiation from the probe circuit. Many of the exercises are for the bench, but some are performed in an NMR system. The exercises should lead to an understanding of, as well as some intuitive knowledge about, basic NMR/MRI probe circuits. © 2012 Wiley Periodicals, Inc. Concepts Magn Reson Part A 40: 1–13, 2012.
A Systematic Study of Electrochemical and Spectral Properties for the Electronic Interactions in Porphyrin–Triphenylamine Conjugates
Authors: Huang Chih‐Yen , Hsu Chao‐Yen , Yang Luo‐Yi , Lee Chia‐Jung , Yang Te‐Fang , Hsu Chia‐Chan , Ke Chung‐Hsiu , Su Yuhlong Oliver 
Published: January 2012

AbstractA series of mono‐, di‐, tri‐, and tetra‐triphenylamine (TPA)‐substituted porphyrinatozinc complexes have been synthesized to investigate their spectral and electrochemical properties. The varied shapes of absorption spectra of porphyrin–triphenylamine (Por–TPA) conjugates in comparison with tetramesitylporphyrinatozinc (ZnTMP) indicate that there are strong interactions between porphyrin and TPA moieties. In general, the electron‐donating capability of a substituent on TPA and the number of TPA derivatives that bond with porphyrin would cause Soret band broadening and intensification of the Q(0,0) band. Due to the antenna effect of these conjugates, the fluorescence quantum yields were enhanced when more TPA moieties were linked. Cyclic voltammetry and spectroelectrochemical methods revealed the redox properties of Por–TPA conjugates. Axial ligation of porphyrinatozinc with N‐methylimidazole was useful in differentiating the oxidation site of Por–TPA conjugates. The first one‐electron oxidations of these conjugates are at the porphyrin ring. The charge‐transfer bands present in the near‐IR region in the absorption spectra of Por–TPA radical cations are evidence of an electronic interaction between porphyrin and TPA. The electron‐donating strength of the TPA group and the symmetry of the Por–TPA conjugate affect the intensity of the charge‐transfer band.
Kβ Detected High‐Resolution XANES of FeII and FeIII Models of the 2‐His‐1‐Carboxylate Motif: Analysis of the Carboxylate Binding Mode
Authors: Mijovilovich Ana , Hayashi Hisashi , Kawamura Naomi , Osawa Hitoshi , Bruijnincx Pieter C. A. , Klein Gebbink Robertus J. M. , de Groot Frank M. F. , Weckhuysen Bert M. 
Published: January 2012

AbstractProteins sharing the same “2‐His‐1‐carboxylate” structural motif have little amino acid sequence similarity and are able to perform many different reactions. Many factors have been cited to explain their different specificity and turnover rates, like protein environment, coordinated ligand geometry, electronic structure of the active site, etc. In this paper, we present a combined approach applying high‐resolution XANES spectroscopy and theory simulations to different model complexes that mimic the binding modes of the amino acids to the metal site. Experiments were performed on three compounds showing three metal sites: ferrous hexacoordinate, ferric pentacoordinate and ferrous pentacoordinate. The first two compounds bear an N,N,O‐tridentate 3,3‐bis(1‐alkylimidazol‐2‐yl)propionate ligand that features a monodentate carboxylate group. These complexes mimic the activity of extradiol dioxygenases but also exhibit intradiol cleavage activity. The third compound features a bidentate terphenylcarboxylate ligand and a sterically hindered bidentate N,N‐donor, thus providing a good structural mimic of the ternary enzyme‐tetrahydrobiopterin‐substrate complex in pterin‐dependent phenylalanine hydroxylase, which also contains a bidentate carboxylate. Modeling of high‐resolution XANES on well‐defined model complexes of different geometry can aid in protein structure elucidation. XANES gives the oxidation state and coordination number of the metal in the non‐crystallized protein at natural pH. The accuracy of the results is limited by the core‐hole and experimental broadenings. We found that high‐resolution XANES experiments give increased resolution at the pre‐edges, but limited improvement at the main edge. These high‐resolution pre‐edges can be accurately simulated by using crystal field multiplet theory (CFM). We show that by combining modelling and XANES simulations with FEFF8, detailed structural and chemical information can be obtained. We found that a short O2–metal distance for the carboxylate oxygen atom not bound to the metal causes a higher white line in FeII, which is similar to the results obtained for the pterin‐dependent hydroxylase, tyrosine hydroxylase (TYH). Full‐potential FDMNES simulations for each sample confirm the accuracy of the main results with muffin‐tin approximation (FEFF8).
Efficient Synthesis of Arylated Flavones by Site‐Selective Suzuki–Miyaura Cross‐Coupling Reactions of the Bis(triflate) of 5,7‐ and 7,8‐Dihydroxyflavone
Authors: Eleya Nadi , Malik Imran , Reimann Sebastian , Wittler Kai , Hein Martin , Patonay Tamás , Villinger Alexander , Ludwig Ralf , Langer Peter 
Published: January 2012

AbstractSuzuki–Miyaura reactions of the bis(triflate) of 5,7‐ and 7,8‐dihydroxyflavone proceed with very good site selectivity in favor of position 7 and allow the synthesis of various arylated flavones. The reaction of 5,7‐dihydroxyflavone with one equivalent of triflic anhydride also proceeds with very good site selectivity in favor of position 7. The subsequent Suzuki–Miyaura reaction of the product allows the synthesis of 7‐aryl‐5‐hydroxyflavones. The regioselectivity is discussed based on DFT calculations.
An Efficient Route to Quinolines and Other Compounds by Iron‐Catalysed Cross‐Dehydrogenative Coupling Reactions of Glycine Derivatives
Authors: Liu Peng , Wang Zhiming , Lin Jue , Hu Xianming 
Published: January 2012

AbstractA simple method has been developed for functionalizing glycine derivatives by iron‐catalysed cross‐dehydrogenative coupling (CDC) reactions. In particular, N‐arylglycine derivatives reacted with alkynes by oxidative C–H/C–H coupling reactions to provide a series of substituted quinolines starting from commercially inexpensive materials. Moreover, N‐arylglycine esters can be oxidatively coupled to ketones by using FeCl3 in the presence of DDQ.
In situ remediation of contaminated sediments using carbonaceous materials
Authors: Rakowska M.I. , Kupryianchyk D. , Harmsen J. , Grotenhuis T. , Koelmans A.A. 
Published: January 2012

Abstract
Carbonaceous materials (CM), such as activated carbons or biochars, have been shown to significantly reduce porewater concentrations and risks by binding hydrophobic organic compounds (HOCs) present in aquatic sediments. In the present study, the authors review the current state-of-the-art use of CM as an extensive method for sediment remediation, covering both technical and ecological angles. The review addresses how factors such as CM type, particle size and dosage, sediment characteristics, and properties of contaminants affect the effectiveness of CM amendment to immobilize HOCs in aquatic sediments. The authors also review the extent to which CM may reduce bioaccumulation and toxicity of HOCs and whether CM itself has negative effects on benthic species and communities. The review is based on literature and datasets from laboratory as well as field trials with CM amendments. The presence of phases such as natural black carbon, oil, or organic matter in the sediment reduces the effectiveness of CM amendments. Carbonaceous material additions appear to improve the habitat quality for benthic organisms by reducing bioavailable HOC concentrations and toxicity in sediment. The negative effects of CM itself on benthic species, if any, have been shown to be mild. The beneficial effects of reducing toxicity at low CM concentrations most probably outweigh the mild negative effects observed at higher CM concentrations. Environ. Toxicol. Chem. 2012;31:693–704. © 2012 SETAC
Numerical control of two‐dimensional shock waves in dual solution domain by instant temperature disturbances
Authors: Alekseev A.K. , Navon I.M. 
Published: January 2012

SUMMARYThe search for the temperature disturbance causing transition between regular and Mach reflections in the dual solution domain is addressed in an optimization statement. The gradient of the discrepancy between the current and target flow fields was calculated using adjoint equations. The control was determined by gradient‐based optimization. The flow field simulation is verified via a posteriori error estimates using the solution of an additional adjoint problem. Copyright © 2012 John Wiley & Sons, Ltd.
Relationship between glial potassium regulation and axon excitability: A role for glial Kir4.1 channels
Authors: Bay Virginia , Butt Arthur M. 
Published: January 2012

AbstractUptake of K+ released by axons during action potential propagation is a major function of astrocytes. Here, we demonstrate the importance of glial inward rectifying potassium channels (Kir) in regulating extracellular K+ ([K+]o) and axonal electrical activity in CNS white matter of the mouse optic nerve. Increasing optic nerve stimulation frequency from 1 Hz to 10–35 Hz for 120 s resulted in a rise in [K+]o and consequent decay in the compound action potential (CAP), a measure of reduced axonal activity. On cessation of high frequency stimulation, rapid K+ clearance resulted in a poststimulus [K+]o undershoot, followed by a slow recovery of [K+]o and the CAP, which were more protracted with increasing stimulation frequency. Blockade of Kir (100 μM BaCl2) slowed poststimulus recovery of [K+]o and the CAP at all stimulation frequencies, indicating a primary function of glial Kir was redistributing K+ to the extracellular space to offset active removal by Na+‐K+ pumps. At higher levels of axonal activity, Kir blockade also increased [K+]o accumulation, exacerbating the decline in the CAP and impeding its subsequent recovery. In the Kir4.1−/− mouse, astrocytes displayed a marked reduction of inward currents and were severely depolarized, resulting in retarded [K+]o regulation and reduced CAP. The results demonstrate the importance of glial Kir in K+ spatial buffering and sustaining axonal activity in the optic nerve. Glial Kir have increasing importance in K+ clearance at higher levels of axonal activity, helping to maintain the physiological [K+]o ceiling and ensure the fidelity of signaling between the retina and brain. © 2012 Wiley Periodicals, Inc.
Bilateral reorganization of posterior temporal cortices in post‐lingual deafness and its relation to cochlear implant outcome
Authors: Lazard Diane S. , Lee Hyo‐Jeong , Truy Eric , Giraud Anne‐Lise 
Published: January 2012

AbstractPost‐lingual deafness induces a decline in the ability to process phonological sounds or evoke phonological representations. This decline is paralleled with abnormally high neural activity in the right posterior superior temporal gyrus/supramarginal gyrus (PSTG/SMG). As this neural plasticity negatively relates to cochlear implantation (CI) success, it appears important to understand its determinants. We addressed the neuro‐functional mechanisms underlying this maladaptive phenomenon using behavioral and functional magnetic resonance imaging (fMRI) data acquired in 10 normal‐hearing subjects and 10 post‐lingual deaf candidates for CI. We compared two memory tasks where subjects had to evoke phonological (speech) and environmental sound representations from visually presented items. We observed dissociations in the dynamics of right versus left PSTG/SMG neural responses as a function of duration of deafness. Responses in the left PSTG/SMG to phonological processing and responses in the right PSTG/SMG to environmental sound imagery both declined. However, abnormally high neural activity was observed in response to phonological visual items in the right PSTG/SMG, i.e., contralateral to the zone where phonological activity decreased. In contrast, no such responses (overactivation) were observed in the left PSTG/SMG in response to environmental sounds. This asymmetry in functional adaptation to deafness suggests that maladaptive reorganization of the right PSTG/SMG region is not due to balanced hemispheric interaction, but to a specific take‐over of the right PSTG/SMG region by phonological processing, presumably because speech remains behaviorally more relevant to communication than the processing of environmental sounds. These results demonstrate that cognitive long‐term alteration of auditory processing shapes functional cerebral reorganization. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.
Visual cognition in disorders of consciousness: From V1 to top‐down attention
Authors: Monti Martin M. , Pickard John D. , Owen Adrian M. 
Published: January 2012

AbstractWhat is it like to be at the lower boundaries of consciousness? Disorders of consciousness such as coma, the vegetative state, and the minimally conscious state are among the most mysterious and least understood conditions of the human brain. Particularly complicated is the assessment of residual cognitive functioning and awareness for diagnostic, rehabilitative, legal, and ethical purposes. In this article, we present a novel functional magnetic resonance imaging exploration of visual cognition in a patient with a severe disorder of consciousness. This battery of tests, first developed in healthy volunteers, assesses increasingly complex transformations of visual information along a known caudal to rostral gradient from occipital to temporal cortex. In the first five levels, the battery assesses (passive) processing of light, color, motion, coherent shapes, and object categories (i.e., faces, houses). At the final level, the battery assesses the ability to voluntarily deploy visual attention in order to focus on one of two competing stimuli. In the patient, this approach revealed appropriate brain activations, undistinguishable from those seen in healthy and aware volunteers. In addition, the ability of the patient to focus one of two competing stimuli, and switch between them on command, also suggests that he retained the ability to access, to some degree, his own visual representations. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.