bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aggregation processes in micellar solutions: a Raman study
Authors: Cazzolli G. , Caponi S. , Defant A. , Gambi C. M. C. , Marchetti S. , Mattarelli M. , Montagna M. , Rossi B. , Rossi F. , Viliani G. 
Published: July 2012

Ionic surfactants such as sodium dodecyl sulfate (SDS) belong to the amphiphile family: they possess a long hydrophobic hydrocarbon chain and a polar hydrophilic headgroup. In a polar solvent and over the critical micellar concentration these molecules join to form micelles. The micellar solutions, in turn, if doped with various ligands tend to aggregate.Solid SDS, micelles of SDS in water and micelles of SDS doped with two types of macrocyclic ligands, Kryptofix 2.2.2 (K222) and crown ether 18‐Crown‐6 (18C6), at different concentrations are studied by Raman scattering, that represents a new approach to such systems.The experimental Raman spectrum, obtained on crystalline powders of SDS, is compared with the ab initio computed spectrum in order to assign the vibrational bands. After discriminating sensitive peaks by comparing the crystalline powders of the single components and their water solutions, the aggregation process and the action of the ligands are analyzed following the evolution of the intensity and wavenumber of these characteristic Raman peaks. This shows that Raman spectroscopy is sensitive to the aggregation dynamics and to the effects induced by the hydration layer on the molecules in solutions. A saturation effect in the aggregation process with the increase of the ligand concentration is observed. Copyright © 2012 John Wiley & Sons, Ltd.
Copolymer Composition Determined by LC‐MALDI‐TOF MS Coupling and “MassChrom2D” Data Analysis
Authors: Weidner Steffen M. , Falkenhagen Jana , Bressler Ingo 
Published: July 2012

AbstractThe MALDI‐TOF MS analysis of copolymers very often results in complex spectra. A chromatographic separation/fractionation prior to the MALDI investigation can be advantageous since the MALDI mass spectra of fractions very often reveal well‐resolved peaks of distinguishable copolymer series. For this purpose, different modes of chromatography have been applied. Chromatographic runs were transferred to MALDI targets utilizing a combined air/electrospray deposition device. Using the new MassChrom2D software, fraction‐dependent 2D copolymer compositions plots were obtained providing additional information on the chromatographic mode, and enabling fast modification of conditions to increase separation.
Flavin‐Functionalized Amphiphilic Block Copolymer Gels
Authors: Fitzpatrick Brian , Creran Brian , Cooke Graeme , Rotello Vincent M. 
Published: July 2012

AbstractThe synthesis of flavin‐containing amphiphilic block copolymers using atom transfer radical polymerisation (ATRP) is described. In these systems, a flavin moiety is engineered into the ATRP initiator unit as an environmental probe and is subsequently used to produce three block copolymers featuring a hydrophobic methacrylate block and a DMAEM block. The dimethylamino unit of the latter is converted to a trimethylammonium unit to afford three amphiphilic block copolymers. Rheological measurements show that these materials form gels in dilute aqueous solution that can be disrupted upon irradiation with ultrasound. The disruption of the gel can be conveniently monitored by exploiting the solvatochromic nature of the S0–S2 absorption in the UV‐vis spectrum in response to its changing environment.
Preparation of Fluorescent Organometallic Porphyrin Complex Nanogels of Controlled Molecular Structure via Reverse‐Emulsion Click Chemistry
Authors: Fu Guo‐Dong , Jiang Hua , Yao Fang , Xu Li‐Qun , Ling Jun , Kang En‐Tang 
Published: July 2012

AbstractHere, we are the first to report a novel approach to preparing well‐defined poly(ethylene glycol) (PEG) fluorescent nanogels, with well‐defined molecular structures and desired functionalities via reverse (mini)emulsion copper(I)‐catalyzed azide‐alkyne cycloaddition (REM‐CuAAC). Nanogels with hydroxyl groups and Ga‐porphyrin complex (Ga‐porphyrin‐OH nanogels), as well as with Ga‐porphyrin complex and folate functional groups (Ga‐porphyrin‐FA), are successfully prepared. Nanogels of 30 and 120 nm in diameter are obtained and they exhibit an emission maxima within the wavelength range 700–800 nm. The nanogels could find uses in near infrared (NIR) imaging attributable to their fluorescence and their functionality for cell affinity.
Amine‐Reactive Polymers Synthesized by RAFT Polymerization Using an Azlactone Functional Trithiocarbonate RAFT Agent
Authors: Ho Hien The , Leroux Flavien , Pascual Sagrario , Montembault Véronique , Fontaine Laurent 
Published: July 2012

AbstractA new azlactone‐derived trithiocarbonate is prepared and used as a chain‐transfer agent to mediate the reversible addition‐fragmentation chain transfer (RAFT) polymerization of styrene, ethyl acrylate, and N‐isopropyl acrylamide. Well‐defined polymers with controlled molecular weights (Mn = 1000–7000 g mol−1) and narrow molecular weight distributions (PDI = 1.05–1.10) are thus obtained that retain the azlactone functionality at the chain end. The ability of the resulting end‐functionalized polymers to react quantitatively at room temperature with a stoichiometric amount of amino groups with retention of the thiocarbonylthio moiety is ascertained by using 4‐fluorobenzylamine and allylamine.
Molecular Weight Determination and Correlation Analysis of Dalbergia sissoo Polysaccharide with Constituent Oligosaccharides
Authors: Kumar Vineet , Rana Vikas , Soni P. L. 
Published: July 2012

ABSTRACTIntroductionMucilaginous polysaccharide extracted from Dalbergia sissoo Roxb. leaves has a number of medicinal applications. Molecular weight studies and correlation analysis of the structure of polysaccharide with oligosaccharides can be helpful for further utilisation, modification and structure–activity relationship for biological applications.ObjectiveTo determine molecular weight of medicinally important polysaccharide. To establish an unequivocal correlation of the polysaccharide monosugars with constituting oligosaccharides and glucuronic acid content based on gas–liquid chromatography (GLC) with the spectrophotometric method.MethodologyComplete and partial hydrolytic studies of pure polysaccharide yielded constituting monosugars and oligosaccharides. The ratio of sugars in polysaccharide and oligosaccharides was studied by preparation of alditol acetates and analysed using GLC. The uronic acid content was studied by GLC analysis and spectrophotometry. Molecular weight of the polysaccharide was determined using the viscometric method.ResultsDalbergia sissoo leaves yielded 14.0% pure polysaccharide, containing 15.7% of glucuronic acid. Complete hydrolysis and GLC analysis of alditol acetate derivatives of reduced and unreduced monosugars indicated the presence of l‐rhamnose, d‐glucuronic acid, d‐galactose and d‐glucose in 1.00:1.00:2.00:2.33 molar ratios. Partial hydrolysis followed by monosugar analysis of oligosaccharides established the monosugar ratio in complete agreement with polysaccharide, thereby corroborating the sugar ratio. Similar uronic acid content was obtained by GLC and spectrophotometry. The polysaccharide had an average molecular weight of 1.5 × 105 Da.ConclusionThe study has established an obvious correlation of the structure of polysaccharide with oligosaccharides, leading to unambiguous identification of monosaccharides, which normally is not studied conclusively while reporting the polysaccharide structure. The molecular weight of the polysaccharide was determined. Copyright © 2012 John Wiley & Sons, Ltd.
Simple and Reliable Methods for the Determination of Three Steroidal Glycosides in the Eight Species of Solanum by Reversed‐phase HPLC Coupled with Diode Array Detection
Authors: Maurya Anupam , Manika N. , Verma Ram Kishore , Singh Subhash C. , Srivastava Santosh Kumar 
Published: July 2012

ABSTRACTIntroductionSolanum species are important ingredients of many traditional Indian medicines and thus the quality control of their herbal formulations is of paramount concern.ObjectiveTo establish a simple and effective high‐performance liquid chromatographic (HPLC) method to evaluate the quality of Solanum species and their herbal formulations.MethodologyA rapid, simple, sensitive, robust and reproducible HPLC method was developed for the determination of three steroidal glycosides (SG); indioside D, solamargine and α‐solanine in eight species of the genus Solanum. The analytes were separated on a monolithic performance RP‐18e column (100 mm × 4.6 mm i.d.) using a gradient elution of acetonitile–water containing 0.1% trifluoroacetic acid (TFA) as the mobile phase with a flow rate 0.4 mL/min and UV detection at λ 210 nm.ResultsThe method was linear over the range 3–15 µg/mL (r > 9994). Accuracy, precision and repeatability were all within the required limits. The mean recoveries measured at the three concentrations were higher than 98.8% with RSD < 2% for the targets.ConclusionThe established method is simple and can be used as a tool for quality control of plant material or herbal formulation containing SG. Copyright © 2012 John Wiley & Sons, Ltd.
Exercise Prescription Patterns in Patients Treated with Vestibular Rehabilitation After Concussion
Authors: Alsalaheen Bara A. , Whitney Susan L. , Mucha Anne , Morris Laura O. , Furman Joseph M. , Sparto Patrick J. 
Published: July 2012

AbstractBackground and PurposeIndividuals with concussion often complain of persistent dizziness and imbalance, and these problems have been treated with vestibular rehabilitation exercises. The purpose of this study is to describe the vestibular rehabilitation exercise prescriptions provided to individuals after concussion.MethodsA retrospective chart review of vestibular rehabilitation home exercise programmes prescribed by physical therapists for 104 participants who were diagnosed with concussion was conducted. Each of the exercises was classified by exercise type, duration and frequency. Frequency counts of the most common exercise types were recorded. Exercise progression patterns were examined by determining how exercise types were modified from visit to visit.ResultsEye–head coordination exercises were the most commonly prescribed exercise type (in 95% of participants), followed by standing static balance exercises (in 88% of participants), and ambulation exercises (in 76% of participants).ConclusionsUnderstanding the prescription patterns of expert clinicians may elucidate the vestibular‐related impairments of individuals after concussion and may provide a resource for therapists who may be starting vestibular rehabilitation programmes for management of individuals with concussion. To improve quality of care, future research should be directed to relate outcomes to the exercise prescription patterns. Copyright © 2012 John Wiley & Sons, Ltd.
Density‐functional‐theory study of α‐cyclodextrin inclusion complexes
Authors: Santillán‐Vargas Hilda , Ramírez José‐Zeferino , Garza Jorge , Vargas Rubicelia 
Published: July 2012

AbstractWe apply the density functional theory on the description of the α‐cyclodextrin (α‐CD) and the analysis of the molecular electrostatic potential (MEP) for complexes of this system with Na+, F−, CO, and N,N‐dimethyl formamide, as substrates. Four exchange‐correlation functionals were considered: one of the local density approximation, two of the generalized gradient approximation (BLYP and PBE), and one of the hybrid family. These exchange‐correlation functionals were coupled with the DZVP/A1, DZVP, and TZVP basis set functions. All complexes were fully optimized by all methods. The experimental molecular structure of the α‐CD compares better with that described by the PBE exchange‐correlation functional. The MEP analysis shows that the electrostatic is quite relevant on the intermolecular interaction for the α‐CD complexes in gas phase. Some of our results are in disagreement with those published previously with the PM3 semiempirical method and the B3LYP//PM3 method. © 2012 Wiley Periodicals, Inc.
DFT in a nutshell
Authors: Burke Kieron , Wagner Lucas O. 
Published: July 2012

AbstractThe purpose of this short essay is to introduce students and other newcomers to the basic ideas and uses of modern electronic density functional theory, including what kinds of approximations are in current use, and how well they work (or not). The complete newcomer should find it orients them well, while even longtime users and aficionados might find something new outside their area. Important questions varying in difficulty and effort are posed in the text, and are answered in the Supporting Information. © 2012 Wiley Periodicals, Inc.
Theoretical study of inclusion of a dinuclear platinum(II) complex in α, β, and γ‐cyclodextrins
Authors: Paixão Nathália Magalhães , Esteves Lucas Fagundes , Anconi Cleber Paulo Andrada , Nascimento Clebio Soares , Almeida Wagner Batista De , Santos Hélio Ferreira Dos , Costa Luiz Antônio Sodré 
Published: July 2012

AbstractThis study has focus on inclusion compounds formed by native cyclodextrins (CD) and dinuclear platinum(II) complex (bisPt), investigated by density functional theory and hybrid our own N‐layered integrated molecular orbital and molecular mechanics (ONIOM) approaches. The main goal here is to get insights on the molecular features governing the stability of bisPt@CD inclusion complexes, accounting for cavity size, host–guest orientation, and stoichiometry. The results indicate that the β‐CD is the most attractive host to form inclusion complex with bisPt, with ΔG found negative for the six orientations tested (A–F), ranging from −3.69 to −20.08 kcal mol−1 (ONIOM values). Besides the favorable size/shape relationship for bisPt@β‐CD complex, the higher stability is also due the hydrogen bonds between the bisPt amine groups and the β‐CD oxygen atoms. © 2012 Wiley Periodicals, Inc.
Quadrupole moment of the hydrogen fluoride using the multireference Hartree–Fock CI method
Authors: Malbouisson Luiz A. C. , de Andrade Micael D. , de C. Sobrinho Antonio M. 
Published: July 2012

AbstractIn this work, the multireference Hartree–Fock configuration interaction method (MRHFCI) was applied to calculate the permanent electrical quadrupole moment of the hydrogen fluoride molecule, using the atomic bases STO‐6G and CFG‐6G. We have obtained MRHFCI functions, with energies comparable to the full CI ones, providing dipole and quadrupole moments in close agreement with the experimental values and with reduced MRHF basis, that is, with significant lower numbers of configurations. © 2012 Wiley Periodicals, Inc.
Theoretical prediction for the structures of gas phase lithium oxide clusters: (Li2O)n (n = 1–8)
Authors: Yuan Yuan , Cheng Longjiu 
Published: July 2012

AbstractWe apply genetic algorithm combining directly with density functional method to search the potential energy surface of lithium‐oxide clusters (Li2O)n up to n = 8. In (Li2O)n (n = 1–8) clusters, the planar structures are found to be global minimum up to n = 2, and the global minimum structures are all three‐dimensional at n ≥ 3. At n ≥ 4, the tetrahedral unit (TU) is found in most of the stable structures. In the TU, the central Li is bonded with four O atoms in sp3 interactions, which leads to unusual charge transformation, and the probability of the central Li participating in the bonding is higher by adaptive natural density partitioning analysis, so the central Li is in particularly low positive charge. At large cluster size, distortion of structures is viewed, which breaks the symmetry and may make energy higher. The global minimum structures of (Li2O)2, (Li2O)6, and (Li2O)7 clusters are the most stable magic numbers, where the first one is planar and the later both have stable structural units of tetrahedral and C4v. © 2012 Wiley Periodicals, Inc.
Is a MH (M = Be and Mg) radical a better electron donor in halogen‐hydride interaction?: A theoretical comparison with HMH
Authors: Bai Xiangbin , Li Qingzhong , Li Ran , Cheng Jianbo , Li Wenzuo 
Published: July 2012

AbstractQuantum chemical calculations have been performed to investigate the complexes of HMHXCCH, HMHXCF3, MHXCCH, and MHXCF3(M = Be and Mg; X = Cl, Br, and I) at the MP2/aug‐cc‐pVTZ level. The geometrical, energetic, and spectroscopic parameters were analyzed for these complexes. The results show that the MH is a better electron donor in the halogen‐hydride interaction than HMH. The enhancement of halogen‐hydride interaction increases in the order of Cl < Br < I, Be < Mg, and XCCH < XCF3. The halogen‐hydride interaction was understood with natural bond orbital, atoms in molecules, and electrostatic potentials. © 2012 Wiley Periodicals, Inc.
Image‐guided hepatopancreatobiliary surgery using near‐infrared fluorescent light
Authors: Verbeek Floris P. R. , van der Vorst Joost R. , Schaafsma Boudewijn E. , Hutteman Merlijn , Bonsing Bert A. , van Leeuwen Fijs W. B. , Frangioni John V. , van de Velde Cornelis J. H. , Swijnenburg Rutger‐Jan , Vahrmeijer Alexander L. 
Published: July 2012

AbstractBackgroundImproved imaging methods and surgical techniques have created a new era in hepatopancreatobiliary (HPB) surgery. Despite these developments, visual inspection, palpation, and intraoperative ultrasound remain the most utilized tools during surgery today. This is problematic, though, especially in laparoscopic HPB surgery, where palpation is not possible. Optical imaging using near‐infrared (NIR) fluorescence can be used for the real‐time assessment of both anatomy (e.g., sensitive detection and demarcation of tumours and vital structures) and function (e.g., assessment of luminal flow and tissue perfusion) during both open and minimally invasive surgeries.MethodsThis article reviews the published literature related to preclinical development and clinical applications of NIR fluorescence imaging during HPB surgery.ResultsNIR fluorescence imaging combines the use of otherwise invisible NIR fluorescent contrast agents and specially designed camera systems, which are capable of detecting these contrast agents during surgery. Unlike visible light, NIR fluorescent light can penetrate several millimetres through blood and living tissue, thus providing improved detectability. Applications of this technique during HPB surgery include tumour imaging in liver and pancreas, and real‐time imaging of the biliary tree.ConclusionsNIR fluorescence imaging is a promising new technique that may someday improve surgical accuracy and lower complications.
Synthesis and Evaluation of Nonionic Polymeric Surfactants Based on Acrylated Polyethylene Glycol
Authors: El Monem Eissa Abd , El Hefnawy Manal , Allah Mohamed Deef 
Published: July 2012

AbstractA novel series of six nonionic polymeric surfactants were prepared by polymerization of acrylated poly(ethylene glycol) (PEG, molecular weight MW = 400, 600 and 2,000) and allyl ester of long chain fatty acid chloride (decanoyl and lauroyl chloride). The unique structural features of these surfactants were confirmed by different spectroscopic tools (IR and 1H NMR). The surface properties of these compounds such as surface tension, interfacial tension, emulsion stability, wetting power, foam height, solubilization and dispersant properties in disperse dye systems were determined and evaluated. A comparison study was done between the chemical structures and surface properties of such compounds. Biodegradability and stability to hydrolysis in acidic and alkaline media were also determined and evaluated.
Sesamin Modulates Gene Expression Without Corresponding Effects on Fatty acids in Atlantic Salmon (Salmo salar L.)
Authors: Schiller Vestergren A. , Wagner L. , Pickova J. , Rosenlund G. , Kamal‐Eldin A. , Trattner S. 
Published: July 2012

AbstractThis study examined the effects of sesamin inclusion in vegetable oil‐based diets fed to Atlantic salmon (Salmo salar L.). The diets used differed in n‐6/n‐3 fatty acid (FA) ratio (0.5 and 1) and sesamin content (high 5.8 g/kg, low 1.16 g/kg and no sesamin). The oils used in the feeds were a mixture of rapeseed, linseed and palm oil. Fish were fed for 4 months. Fatty acids and expression of hepatic genes involved in transcription, lipid uptake, desaturation, elongation and β‐oxidation were measured. No major effects on the percentage of DHA in white muscle, liver triacylglycerol and phospholipid fraction were detected. Genes involved in β‐oxidation, elongation and desaturation were affected by sesamin addition. Limited effects were seen on any of the transcription factors tested and no effect was seen on the expression of peroxisome proliferator‐activated receptors (PPAR). Expression of both SREBP‐1 and SREBP‐2 increased with sesamin addition. It was concluded that supplementation of fish feed with a high level of sesamin had a negative effect on the growth rate and live weight and did not alter the proportions of DHA in tissues even though gene expression was affected. Thus, more studies are needed to formulate a diet that would increase the percentage of DHA in fish without negative effects on fish growth.
Sozialepidemiologie
Authors: Spallek Jacob , Kuntz Benjamin , Schott Thomas 
Published: July 2012

Einleitung
Sozialepidemiologie untersucht, ob und in welchem Maße gesellschaftlich benachteiligte Bevölkerungsgruppen auch gesundheitlich benachteiligt sind. Soziale Ungleichheit, definiert anhand vertikaler (SES) und horizontaler (z.B. Geschlecht, Migrationsstatus) Indikatoren, hat über Selektionseffekte, materielle und strukturelle Faktoren und unterschiedliche Verhaltensweisen einen Einfluss auf die Gesundheit. Neben der Untersuchung sozialer Determinanten gesundheitlicher Ungleichheit stehen zunehmend auch die Erforschung salutogener sozialer Faktoren und die Einbeziehung einer Lebenslaufperspektive im Fokus sozialepidemiologischer Forschung.
Existence and properties of ageostrophic modons and coherent tripoles in the two-layer rotating shallow water model on the -plane
Authors: Lahaye Noé , Zeitlin Vladimir 
Published: July 2012

AbstractWe study formation and properties of new coherent structures: ageostrophic modons in the two-layer rotating shallow water model. The ageostrophic modons are obtained by ‘ageostrophic adjustment’ of the exact modon solutions of the two-layer quasi-geostrophic equations with the free surface, which are used to initialize the full two-layer shallow water model. Numerical simulations are performed using a well-balanced high-resolution finite volume numerical scheme. For large enough Rossby numbers, the initial configurations undergo ageostrophic adjustment towards asymmetric ageostrophic quasi-stationary coherent dipoles. This process is accompanied by substantial emission of inertia–gravity waves. The resulting dipole is shown to be robust and survives frontal collisions. It contains captured inertia–gravity waves and, for higher Rossby numbers and weak stratification, carries a (baroclinic) hydraulic jump at its axis. For stronger stratifications and high enough Rossby numbers, ‘rider’ coherent structures appear as a result of adjustment, with a monopole in one layer and a dipole in another. Other ageostrophic coherent structures, such as two-layer tripoles and two-layer modons with nonlinear scatter plot, result from the collisions of ageostrophic modons. They are shown to be long-living and robust, and to capture waves.