bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crystal Engineering of Stable Temozolomide Cocrystals
Authors: Babu N. Jagadeesh , Sanphui Palash , Nangia Ashwini 
Published: May 2012

AbstractThe antitumor prodrug temozolomide (TMZ) decomposes in aqueous medium of pH≥7 but is relatively stable under acidic conditions. Pure TMZ is obtained as a white powder but turns pink and then brown, which is indicative of chemical degradation. Pharmaceutical cocrystals of TMZ were engineered with safe coformers such as oxalic acid, succinic acid, salicylic acid, d,l‐malic acid, and d,l‐tartaric acid, to stabilize the drug as a cocrystal. All cocrystals were characterized by powder X‐ray diffraction (PXRD), single crystal X‐ray diffraction, and FT‐IR as well as FT‐Raman spectroscopy. Temozolomide cocrystals with organic acids (pKa 2–6) were found to be more stable than the reference drug under physiological conditions. The half‐life (T1/2) of TMZ–oxalic and TMZ–salicylic acid measured by UV/Vis spectroscopy in pH 7 buffer is two times longer than that of TMZ (3.5 h and 3.6 h vs. 1.7 h); TMZ–succinic acid, TMZ–tartaric acid, and TMZ–malic acid also exhibited a longer half‐life (2.3, 2.5, and 2.8 h, respectively). Stability studies at 40 °C and 75 % relative humidity (ICH conditions) showed that hydrolytic degradation of temozolomide in the solid state started after one week, as determined by PXRD, whereas its cocrystals with succinic acid and oxalic acid were intact at 28 weeks, thus confirming the greater stability of cocrystals compared to the reference drug. The intrinsic dissolution rate (IDR) profile of TMZ–oxalic acid and TMZ–succinic acid cocrystals in buffer of pH 7 is comparable to that of temozolomide. Among the temozolomide cocrystals examined, those with succinic acid and oxalic acid exhibited both an improved stability and a comparable dissolution rate to the reference drug.
Macroscopic Self‐Propelled Objects
Authors: Zhao Guanjia , Pumera Martin 
Published: May 2012

AbstractSelf‐propelled systems are currently in the spotlight of the research community. We review the progress of the construction of both millimeter‐ and centimeter‐sized self‐propelled macroscopic objects. We will also discuss the various sources of energy used by these systems, such as the electromagnetic field, electric field, thermal gradient, and chemical energy, and present how these millimeter‐ and centimeter‐sized devices can move at velocities of tens cm s−1 and distances of several tens of meters.
An integrated process for removing the inhibitors of the prehydrolysis liquor of kraft‐based dissolving pulp process via cationic polymer treatment
Authors: Saeed Abrar , Fatehi Pedram , Ni Yonghao 
Published: May 2012

AbstractThe prehydrolysis liquor (PHL) of the kraft‐based dissolving pulp production process contains various amounts of hemicelluloses that can be utilized in the production of value‐added products. In this work, a new process was proposed for removing the inhibitors of PHL via employing a flocculation concept to facilitate the utilization of hemicelluloses. Lignin, lignocelluloses/cationic polymer complexes, and possibly ethanol are the main products of this process. This process has been experimentally evaluated with an industrially produced PHL and cationic polymers. The results showed that 16% of lignin, 19% of acetic acid, 43% of furfural, and insignificant amount of sugars were removed from PHL via pretreating PHL with acid and lime at pH 7. Furthermore, by adding 0.4–0.5 mg g−1 polydiallyldimethylammonium chloride (PDADMAC) or chitosan to the pretreated PHL, 12–14% acetic acid, 40–50% furfural, 5–6% monomeric sugars, and 25% oligomeric sugars were removed from the PHL. The complexes made from these components may be applied as organic fillers in various industries. Alternatively, by adding 1.2 or 1.4 mg g−1 PDADMAC or chitosan to the pretreated PHL, 30 or 35% of lignin was removed, respectively, which induced complexes that could be used as a fuel source. The composition of the complexes formed was also determined in this work. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 28: 998–1004, 2012
Investigating the Halochromic Properties of Azo Dyes in an Aqueous Environment by Using a Combined Experimental and Theoretical Approach
Authors: De Meyer Thierry , Hemelsoet Karen , Van der Schueren Lien , Pauwels Ewald , De Clerck Karen , Van Speybroeck Veronique 
Published: May 2012

AbstractThe halochromism in solution of a prototypical example of an azo dye, ethyl orange, was investigated by using a combined theoretical and experimental approach. Experimental UV/Vis and Raman spectroscopy pointed towards a structural change of the azo dye with changing pH value (in the range pH 5–3). The pH‐sensitive behavior was modeled through a series of ab initio computations on the neutral and various singly and doubly protonated structures. For this purpose, contemporary DFT functionals (B3LYP, CAM‐B3LYP, and M06) were used in combination with implicit modeling of the water solvent environment. Static calculations were successful in assigning the most‐probable protonation site. However, to fully understand the origin of the main absorption peaks, a molecular dynamics simulation study in a water molecular environment was used in combination with time‐dependent DFT (TD‐DFT) calculations to deduce average UV/Vis spectra that take into account the flexibility of the dye and the explicit interactions with the surrounding water molecules. This procedure allowed us to achieve a remarkable agreement between the theoretical and experimental UV/Vis spectrum and enabled us to fully unravel the pH‐sensitive behavior of ethyl orange in aqueous environment.
Reactive Half‐Metallocenium Ionic Liquids That Undergo Solventless Ligand Exchange
Authors: Inagaki Takashi , Mochida Tomoyuki 
Published: May 2012

AbstractThe piano‐stool half‐metallocenium cations [Fe(C5R5)(CO)2L]+ (C5R5=C5H5, C5Me5, C5Me4Et; L=1‐pentene, nBuCN, MeCN, Me2S, NH3, NMe3, pyridine) provide ionic liquids (ILs) with the bis(trifluoromethanesulfonyl)imide (Tf2N) anion without introducing long alkyl chains. Their melting points are affected by molecular symmetry, and their thermal stabilities reflect the strength of the metal–ligand bonding. These are reactive liquids that show solventless ligand exchange reactions by gas absorption. The direction of the ligand‐exchange reaction is correlated with the stabilities. Based on the variation of the melting points, these ILs undergo transformations between the liquid and solid phases associated with the reaction.
Long‐Lived Room‐Temperature Deep‐Red‐Emissive Intraligand Triplet Excited State of Naphthalimide in Cyclometalated IrIII Complexes and its Application in Triplet‐Triplet Annihilation‐Based Upconversion
Authors: Sun Jifu , Wu Wanhua , Zhao Jianzhang 
Published: May 2012

AbstractCyclometalated IrIII complexes with acetylide ppy and bpy ligands were prepared (ppy=2‐phenylpyridine, bpy=2,2′‐bipyridine) in which naphthal (Ir‐2) and naphthalimide (NI) were attached onto the ppy (Ir‐3) and bpy ligands (Ir‐4) through acetylide bonds. [Ir(ppy)3] (Ir‐1) was also prepared as a model complex. Room‐temperature phosphorescence was observed for the complexes; both neutral and cationic complexes Ir‐3 and Ir‐4 showed strong absorption in the visible range (ε=39600 M−1 cm−1 at 402 nm and ε=25100 M−1 cm−1 at 404 nm, respectively), long‐lived triplet excited states (τT=9.30 μs and 16.45 μs) and room‐temperature red emission (λem=640 nm, Φp=1.4 % and λem=627 nm, Φp=0.3 %; cf. Ir‐1: ε=16600 M−1 cm−1 at 382 nm, τem=1.16 μs, Φp=72.6 %). Ir‐3 was strongly phosphorescent in non‐polar solvent (i.e., toluene), but the emission was completely quenched in polar solvents (MeCN). Ir‐4 gave an opposite response to the solvent polarity, that is, stronger phosphorescence in polar solvents than in non‐polar solvents. Emission of Ir‐1 and Ir‐2 was not solvent‐polarity‐dependent. The T1 excited states of Ir‐2, Ir‐3, and Ir‐4 were identified as mainly intraligand triplet excited states (3IL) by their small thermally induced Stokes shifts (ΔEs), nanosecond time‐resolved transient difference absorption spectroscopy, and spin‐density analysis. The complexes were used as triplet photosensitizers for triplet‐triplet annihilation (TTA) upconversion and quantum yields of 7.1 % and 14.4 % were observed for Ir‐2 and Ir‐3, respectively, whereas the upconversion was negligible for Ir‐1 and Ir‐4. These results will be useful for designing visible‐light‐harvesting transition‐metal complexes and for their applications as triplet photosensitizers for photocatalysis, photovoltaics, TTA upconversion, etc.
Neutral and Anionic Guests and Their Effect on the Formation of Pseudorotaxanes by Using a Flexible Tetracationic Imidazolium Macrocycle
Authors: Gong Han‐Yuan , Rambo Brett M. , Lynch Vincent M. , Keller Karin M. , Sessler Jonathan L. 
Published: May 2012

AbstractThe ability to control and direct molecular assembly has important implications in the design of environmentally responsive materials. Reported here is the use of competitive neutral‐ and anionic‐guest recognition to control the formation, disruption, replacement‐based construction and higher‐order assembly properties of pseudorotaxane structures involving a large, cationic tetraimidazolium receptor. In particular, we showed that the chloride anion (as the tetrabutylammonium (TBA+) salt) serves to replace directly the 2,6‐naphthalene dicarboxylate dianion from the preformed complex, involving this dianion. In contrast, the addition of the nitrate anion (as the TBA+ salt) serves to effect displacement of a pre‐bound 2,6‐naphthalene dicarboxylate dianion in a stepwise manner allowing for stabilization of a so‐called “outside”‐binding mode under appropriate conditions. We have also found that by using biphenyl‐3,4,3′,4′‐tetraamine as the guest, a 1D‐donor–acceptor–donor coordination polymer can be stabilized, whereas the addition of 6‐amino‐naphthalene‐2‐sulfonate anion to the pre‐formed complex between the tetraimidazolium receptor and the 2,6‐naphthalene dicarboxylate dianion produces a new pseudorotaxane complex. This guest‐based competition and subsequent molecular translocation is supported by solution‐state NMR spectroscopic studies as well as solid‐state single‐crystal X‐ray structural analyses. The results described herein provide initial evidence that guest competition can be used to control molecular “switching” and substrate binding within an appropriately designed anion receptor.
Low‐Temperature Route to Crystalline Titania Network Structures in Thin Films
Authors: Rawolle Monika , Braden Erik V. , Niedermeier Martin A. , Magerl David , Sarkar Kuhu , Fröschl Thomas , Hüsing Nicola , Perlich Jan , Müller‐Buschbaum Peter 
Published: May 2012

AbstractA low temperature route to crystalline titania nanostructures in thin films is presented. The synthesis is performed by the combination of sol‐gel processes, using a novel precursor for this kind of application, an ethylene glycol‐modified titanate (EGMT), and the structure templating by micro‐phase separation of a di‐block copolymer. Different temperatures around 100 °C are investigated. The nanostructure morphology is examined with scanning electron microscopy, whereas the crystal structure and thin film compositions are examined by scattering methods. Optoelectronic measurements reveal the band‐gap energies and sub‐band states of the titania films. An optimum titania thin film is created at temperatures not higher than 90 °C, regarding sponge‐like morphology with pore sizes of 25–30 nm, porosity of up to 71 % near the sample surface, and crystallinity of titania in the rutile phase. The low temperature during synthesis is of high importance for photovoltaic applications and renders the resulting titania films interesting for future energy solutions.
Recent Progress and Challenges in Graphene Nanoribbon Synthesis
Authors: Ma Liang , Wang Jinlan , Ding Feng 
Published: May 2012

AbstractGraphene, the thinnest two‐dimensional material in nature, has abundant distinctive properties, such as ultrahigh carrier mobility, superior thermal conductivity, very high surface‐to‐volume ratio, anomalous quantum Hall effect, and so on. Laterally confined, thin, and long strips of graphene, namely, graphene nanoribbons (GNRs), can open the bandgap in the semimetal and give it the potential to replace silicon in future electronics. Great efforts are devoted to achieving high‐quality GNRs with narrow widths and smooth edges. This minireview reports the latest progress in experimental and theoretical studies on GNR synthesis. Different methods of GNR synthesis—unzipping of carbon nanotubes (CNTs), cutting of graphene, and the direct synthesis of GNRs—are discussed, and their advantages and disadvantages are compared in detail. Current challenges and the prospects in this rapidly developing field are also addressed.
A Self‐help, Positive Goal‐focused Intervention to Increase Well‐being in People with Depression
Authors: Coote Helen M. J. , MacLeod Andrew K. 
Published: May 2012

Self‐help interventions are an accessible, first‐step treatment for depression. Well‐being interventions focus on increasing people's resources and bringing about positive feelings and behaviours and could enhance self‐help interventions for depression by increasing well‐being as well as reducing depression. The present study tested the effectiveness of a self‐help, well‐being intervention (Goal‐setting and Planning, GAP) in both increasing well‐being and reducing depression within a sample from a depression self‐help organization. We used a cross‐over design, with half of the participants allocated to GAP (n = 26) and half to a wait‐list control group (n = 29). After 5 weeks, the wait‐list control group also received GAP. Compared with wait‐list controls, those allocated to GAP showed an overall positive change, with individual significant decreases in negative affect and trends towards significant decreases in depression and increases in positive affect and life satisfaction post‐intervention. Within a cross‐over design, the wait‐list controls also received GAP. In the whole sample that received GAP, there were significant increases in positive affect and life satisfaction and significant decreases in negative affect and depression, post‐intervention and at 5‐week follow‐up, relative to baseline. These findings demonstrate that GAP is a useful intervention for people with symptoms of depression, influencing both levels of well‐being and depressive symptoms. Copyright © 2012 John Wiley & Sons, Ltd.Key Practitioner Message

Self‐help interventions have been found to be effective in depression.
There are positively focused self‐help interventions that have been designed to increase well‐being in the general population.
In the present study, one such intervention—Goal‐setting and Planning (GAP) Skills training was found to improve well‐being and reduce depression in those with a long history of depression.
The Double‐Edged Sword of Goal Engagement: Consequences of Goal Pursuit in Bipolar Disorder
Authors: Johnson Sheri L. , Fulford Daniel , Carver Charles S. 
Published: May 2012

A series of studies suggest that bipolar disorder is related to high sensitivity to incentives and that incentive sensitivity (or sensitivity of the approach system) can predict the course of mania. Incentive sensitivity in bipolar disorder seems to be related to two processes: a tendency to invest in difficult‐to‐attain goals and an over‐reactivity to cues of goal progress versus thwarting. Both of those processes appear relevant to symptom generation. Hence, bipolar disorder seems related to a greater emphasis on reaching goals and also a problematic reactivity to reaching those highly desired goals. We suggest directions for treatment development focused on these issues in goal regulation. Copyright © 2012 John Wiley & Sons, Ltd.Key Practitioner Message

For people with bipolar disorder, heightened approach motivation appears to be manifested in setting extremely high goals, expending extraordinary resources towards those goals and reacting in more prolonged ways to goal progress or thwarting.
Early prodromal signs of mania may involve increased goal pursuit and heightened activity.
Each of these facets could potentially be amenable to cognitive behavioural intervention.
The Impact of CEO Characteristics on Corporate Sustainable Development
Authors: Huang Shihping Kevin 
Published: May 2012

ABSTRACTThis study explores the relationship between CEO demographic characteristics and consistency in corporate social responsibility (CSR) performance among firms. The sample is based on results from major ranking agencies between 2005 and 2010. A total of 661 firms were included in the sample with 392 observations in total. The results indicate that firms' CSR performance, as measured by the consistency of their CSR rankings, is associated with their CEOs' educational specializations in Master's‐level business administration (MBA) and science (MSc). In addition, CEO tenure and gender are shown to affect firms' CSR performance. Furthermore, a firm's number of employees also has a significant relationship with its CSR performance. The results are encouraging for supporting universities' efforts to integrate CSR issues into their curricula. Copyright © 2012 John Wiley & Sons, Ltd and ERP Environment.
Importance of OH− Transport from Cathodes in Microbial Fuel Cells
Authors: Popat Sudeep C. , Ki Dongwon , Rittmann Bruce E. , Torres César I. 
Published: May 2012

AbstractCathodic limitation in microbial fuel cells (MFCs) is considered an important hurdle towards practical application as a bioenergy technology. The oxygen reduction reaction (ORR) needs to occur in MFCs under significantly different conditions compared to chemical fuel cells, including a neutral pH. The common reason cited for cathodic limitation is the difficulty in providing protons to the catalyst sites. Here, we show that it is not the availability of protons, but the transport of OH− from the catalyst layer to the bulk liquid that largely governs cathodic potential losses. OH− is a product of an ORR mechanism that has not been considered dominant before. The accumulation of OH− at the catalyst sites results in an increase in the local cathode pH, resulting in Nernstian concentration losses. For Pt‐based gas‐diffusion cathodes, using polarization curves developed in unbuffered and buffered solutions, we quantified this loss to be >0.3 V at a current density of 10 A m−2. We show that this loss can be partially overcome by replacing the Nafion binder used in the cathode catalyst layer with an anion‐conducting binder and by providing additional buffer to the cathode catalyst directly in the form of CO2, which results in enhanced OH− transport. Our results provide a comprehensive analysis of cathodic limitations in MFCs and should allow researchers to develop and select materials for the construction of MFC cathodes and identify operational conditions that will help minimize Nernstian concentration losses due to pH gradients.
Microbial Catalysis of the Oxygen Reduction Reaction for Microbial Fuel Cells: A Review
Authors: Erable Benjamin , Féron Damien , Bergel Alain 
Published: May 2012

AbstractThe slow kinetics of the electrochemical oxygen reduction reaction (ORR) is a crucial bottleneck in the development of microbial fuel cells (MFCs). This article firstly gives an overview of the particular constraints imposed on ORR by MFC operating conditions: neutral pH, slow oxygen mass transfer, sensitivity to reactive oxygen species, fouling and biofouling. A review of the literature is then proposed to assess how microbial catalysis could afford suitable solutions. Actually, microbial catalysis of ORR occurs spontaneously on the surface of metallic materials and is an effective motor of microbial corrosion. In this framework, several mechanisms have been proposed, which are reviewed in the second part of the article. The last part describes the efforts made in the domain of MFCs to determine the microbial ecology of electroactive biofilms and define efficient protocols for the formation of microbial oxygen‐reducing cathodes. Although no clear mechanism has been established yet, several promising solutions have been recently proposed.
Immunohistochemical detection of estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 in formalin‐fixed breast carcinoma cell block preparations: Correlation of results to corresponding tissue block (needle core and excision) samples
Authors: Kinsella Mary D. , Birdsong George G. , Siddiqui Momin T. , Cohen Cynthia , Hanley Krisztina Z. 
Published: May 2012

AbstractEvaluation of ER, PR and Her 2 are routinely performed on breast carcinomas. For accurate detection of these markers, compliance with the ASCO/CAP guidelines is recommended.Our previous study showed that alcohol fixation did not affect ER results when alcohol‐fixed cell block (CB) sections were compared to formalin‐fixed tissue sections, while PR and Her2 showed less concordance.The aim of this study was to evaluate and to compare ER, PR and Her2 IHC results on formalin‐fixed CB sections to those observed on subsequent surgical (needle core or resection) specimens (SS).Fifty cases of formalin fixed CB samples obtained from primary (18%) and metastatic (82%) breast carcinomas were studied, all of which had subsequent SS available. ER, PR, and Her2 IHC studies were done on all samples and results were compared.ER results on formalin‐fixed CB samples showed excellent correlation with SS (correlation coefficient cc = 0.82). While there was minimal improvement in PR results (cc = 0.433), Her2 detection did not improve by formalin fixation (cc = 0.439). Formalin fixation for CB preparations does not significantly improve the already good detection of ER positive breast tumors. The concordance rate in PR and IHC results between formalin‐fixed CB and SS samples showed improvement as compared with the alcohol‐fixed CB results. However, there was no improvement in detection of Her2 overexpression by using formalin fixation on cytology specimens. Diagn. Cytopathol. 2013. © 2012 Wiley Periodicals, Inc.
Voltammetric Determination of BHT Antioxidant at Gold Electrode in Biodiesel
Authors: Chýlková Jaromíra , Tomášková Markéta , Mikysek Tomáš , Šelešovská Renáta , Jehlička Jan 
Published: May 2012

AbstractThe voltammetric determination of synthetic antioxidant 2,6‐di‐tert‐butyl‐4‐methylphenole (BHT) was studied using linear‐sweep voltammetry (LSV) and cyclic voltammetry (CV) with a gold electrode and performed in isopropanol media containing either 0.1 mol L−1 H2SO4 or 0.1 mol L−1 LiClO4 as supporting electrolyte. The results obtained have revealed that the most reliable detection was acquired in acidic media (isopropanol–H2SO4) whereas the use of isopropanolLiClO4 solution exhibited poorer reproducibility due to possible passivation of the electrode. Real samples of biodiesel mixture were analyzed without any special sample treatment or separation and results were compared with those obtained by FTIR‐spectroscopy.