bluuebunny/crossref_metadata_2025_split huggingface dataset:
Montmorillonite — S‐Triazine Interactions
Authors: Cruz Maribel , White J. L. , Russell J. D. 
Published: November 2013

AbstractAdsorption of s‐triazines on montmorillonite surfaces results in hydrolysis and protonation of the s‐triazine compounds. Infrared studies suggest that dissociation of adsorbed water on the clay surface plays a major role in protonation and hydrolysis of the s‐triazine herbicides.
Statistical Models in the Study of Soil Properties
Authors: Karmeli D. , Kinsky J. 
Published: November 2013

AbstractAn objective study of soil properties is presented by means of statistical analysis using the least squares method. Elevation data and clay content, from six regions of an overall surveyed area, are approximated by linear and quadratic matrices. Regressions between a defined topography index of mean slopes and clay content are established. The level of significance of the relations is examined by means of computed “accounted map variability” and correlation coefficients. The results express the trend of the investigated property.
A Relationship Between the Conductivity and the Chloride Content in the Soil Extract and the Electromotive Force of the Soil Solution In Situ
Authors: Rinot M. , Goldberg S. D. 
Published: November 2013

AbstractThe electromotive force (emf) of a silver — silver chloride electrode in contact with moist clay loam, was found to be related to the specific conductivity of the 1:3 soil‐water extract. The chloride concentration of the extract was also well correlated with conductivity. Data from other sources show a generally similar trend existing for the variation of chloride concentration with conductivity of soil extracts from widely different soils. The proportion of chloride in the solution increases with total concentration, approaching a constant value at high concentrations. The relation of emf to the concentration, and its possible practical significance is noted.
Charge‐Transfer Complexes Between N‐Heteroaromatic Bases and their Salts
Authors: Shinitzky M. 
Published: November 2013

AbstractAcridine, quinoline and isoquinoline are shown to form 1:1 charge transfer complexes with their protonated or methylated positively charged forms. The complexes exhibit characteristic charge‐transfer bands, part of which fall in the region where the components of the complex show no light absorption. The association constant K for mixtures containing acridine, quinoline or isoquinoline and their hydrochlorides or methochlorides in methanol‐water was derived from changes in intensity of the apparent charge‐transfer band with concentration of the free base. For the above mixtures in water, the association constant as well as the heat of complex formation ΔH were derived. The values of K and ΔH for the complexes formed between each of the three bases and their protonated forms are considerably higher than the analogous values for the complex with the methylated form, presumably due to a hydrogen bond between the coupled base molecules.
Preliminary Studies of the NMR Spectra of N‐Benzyl‐6‐Substituted Purines
Authors: Neiman Z. 
Published: November 2013

AbstractIn 7‐benzyl‐6‐mercaptopurine the benzylic methylene resonates at a lower magnetic field compared to other N‐benzyl groups and can be easily characterized. This deshielding effect is attributed to the magnetic anisotropy of the carbon6‐sulphur bond. In trifluoroacetic acid a slow proton‐exchange is observed for 1‐and 3‐benzyl‐6‐mercaptopurines but not for N‐benzyladenines.
Resolution Of N‐Benzyl‐Erythro‐β‐Hydroxy‐DL‐Aspartic Acid
Authors: Liwschitz Y. , Singerman A. , Wiesel Y. 
Published: November 2013

AbstractDakin's method for the resolution of erythro‐β‐hydroxy‐DL‐aspartic acid gives only incomplete separation. The N‐benzyl derivative of this amino acid, however, has been resolved by means of L‐histidine. Both antipodes are obtained optically pure and in practically quantitative yield.
The ISO‐Tetrahydrocannabinols
Authors: Gaoni Y. , Mechoulam R. 
Published: November 2013

AbstractSynthetic routes are described which lead to iso‐tetrahydrocannabinols, a new series of structural isomers of the natural Δ1‐tetrahydrocannabinol. In this group of compounds a dihydrobenzopyran ring system is formed by cyclization of one of the phenolic groups of a cannabinoid with the C1 carbon in the terpene moiety of the molecule.
Mixed Valence Compounds of Vanadium II. Properties and Formation Mechanism
Authors: Heitner‐Wirguin C. , Selbin J. 
Published: November 2013

AbstractA second mixed valence compound of vanadium was obtained by decomposition of vanadyl (IV)bis (acetylacetonate) by fluoride ions in a nonpolar solvent. The compound has the formula [(C2H5)4N]4[V10O26F2H2] i.e. two oxygens of the previous compound [(C2H5)4N]4[V10O28H4] were replaced by fluoride ions. The thermal stability, electronic and ESR spectra are described. The properties of this compound are very similar to the compound obtained by addition of a halide ion (chloride, bromide or iodide) to vanadyl(IV) bis (acetylacetonate) in the presence of another metal complex. The mechanism of formation of these compounds is discussed.
Photoaddition of Acetylcyclohexane and Ethanol
Authors: Rubin M. B. 
Published: November 2013

Abstract1‐Acetylcyclohexene undergoes photoaddition with ethanol to give, initially, cis‐ and trans‐2‐ethoxy‐1‐acetylcyclohexane. The thermodynamically less stable cis isomer is the major product. No products resulting from photochemical hydrogen atom abstraction from ethanol by photoexcited ketone were observed in contrast to the results obtained with an acetylcyclopentene derivative. The initially formed adducts undergo a further photochemical reaction, intramolecular hydrogen atom abstraction, to give derivatives of octahydrobenzofuran. Quantum yields for disappearance of acetylcyclohexene in ethanol were 0.04 at 2537Å and 0.25 at 3130Å.
Studies on Rat Liver Glutamine Synthetase
Authors: Gutter B. , Spiegelstein‐Klarfeld Hanna , Lichtenstein N. 
Published: November 2013

AbstractRat liver glutamine synthetase is activated by Mg++ and by Mn++. Optimal activity of the Mg++ activated synthetase occurred at about pH 7.8. The pH optimum of the Mn++ activated enzyme varied from 6.2 at low Mn++concentrations to 4.4 at high Mn++concentrations. α‐N‐Ethyl‐L‐glutamine inhibits the synthetase activity. The inhibition is of a mixed type. The synthetase is also inhibited, to a lesser degree, by α‐N‐propyl‐L‐glutamine but not by α‐N‐butyl‐L‐glutamine.
Fulvenes and Thermochromic Ethylenes. Part 52 The Fine Structure of 2‐Arylmethylene‐1,3‐Indandiones; their NMR and Infrared Spectra
Authors: Agranat I. , Loewenstein Ruth M. J. , Bergmann E. D. 
Published: November 2013

AbstractA large number of 2‐arylmethylene‐1,3‐indandiones have been prepared and their nuclear magnetic resonance and infrared spectra have been measured. The measurements have been used to elucidate some details of the fine structure of these compounds.
Reactions Between Fulvic Acid, A Soil Humic Compound, and Montmorillonite
Authors: Schnitzer M. , Kodama H. 
Published: November 2013

AbstractThe magnitudes of d001 spacings of fulvic acid‐Na‐montmorillonite complexes were not affected by temperatures between 25 and 60°C. Slightly more than one half of the total amount of fulvic acid adsorbed by Na‐montmorillonite was in the interlamellar spaces, with the remainder on external surfaces. The d001 spacings and amounts of fulvic acid adsorbed in the interlamellar spaces of Pb++−, Mg++−, Co++− and Ni++− saturated montmorillonite decreased with increase in pH. The capacities of cation saturated clays to adsorb fulvic acid in interlamellar spaces decreased in the following order: Pb++ > Mg++ > Co++ > Ni++. The exotherm near 670°C in the DTA curve of the fulvic acid‐Na‐montmorillonite complex signalized the formation of an interlayer complex.
Copper Complexes Obtained from the Schiff Base of Quinoline‐2‐Aldehyde and Aliphatic Diamines
Authors: Kirson B. , Kassierer F. 
Published: November 2013

AbstractSchiff base bis (2— quinolidene)‐ diamine gives a purple‐red complex with copper ions with a λmax at 530 mμ. The optimum pH for production of this complex is approximately 9.5. None of the metallic ions of the analytical groups II and III give rise to red complexes with the above Schiff base. Manganous (Mn2+) and stannous (Sn2+)ions as well as reducing agents such as hydrazine or hydroxylamine exert a catalytic effect on the rate of formation of these copper complexes. The thermal stability of the copper complex formed from the Schiff bases (2‐quinoline‐aldehyde with NH2‐(CH2)n‐NH2) is greater for diamine for which n = 4–6 than for n = 2–3.
Pyrolytic Reactions of Carbohydrates. Part V. Isothermal Decomposition of Cellulose in Vacuo
Authors: Halpern Y. , Patai S. 
Published: November 2013

AbstractThe thermal decomposition of cellulose in vacuo at 250,275 and 300°C was studied. The decomposition products appearing in different fractions were analyzed and the product ratios at different stages of the reaction were determined. A general scheme is proposed for the process.
Pyrolytic Reactions of Carbohydrates. Part VI. Isothermal Decomposition of Cellulose In Vacuo, in the Presence of Additives
Authors: Halpern Y. , Patai S. 
Published: November 2013

AbstractThe isothermal decomposition of cellulose at 250 and 275°C has been investigated in the presence of neutral, acidic, and basic additives. The composition of the volatile fractions and of the residue has been studied and the influence of the additives on the course of the thermal decomposition is discussed.
Pyrolytic Reactions of Carbohydrates, Part VIII. The Decomposition of D‐Glucose Labelled with 14C at Different Positions, Catalyzed by Various Additives
Authors: Houminer Y. , Hoz S. , Patai S. 
Published: November 2013

AbstractThe thermal decomposition of D‐glucose labelled with 14C either uniformly or at positions 1, 2 or 6 was studied at 250°C, in the presence of NaHCO3, CH3COONa, NaHSO4, NaH2PO4 or oxygen. The aqueous and tarry fractions were analysed and the amount and radioactivity of the evolved carbon dioxide and monoxide were determined. The effect of the additives on the pyrolytic processes, especially on the formation of the oxides of carbon is discussed. The presence of basic additives reduces the selectivity of different carbon atoms in the formation of volatiles. Both oxygen and nitrogen promote the formation of CO.
Simplistic Analysis of Reactive Scattering II. Initial and Final Distortions
Authors: Levine R. D. 
Published: November 2013

AbstractThe angular distribution of reactively scattered molecules is discussed in terms of a classical optical model. The deflection in a reactive scattering is considered, for direct reactions, as the sum of an initial and final deflection. The formal validation of this approach is discussed with a distorted wave approach and within a more general, reaction matrix formulation.
Transient Species in the Laser Photolysis at 265 Mμ of the Halogenobenzenes in Solution
Authors: Loeff I. , Lutz H. , Lindqvist L. 
Published: November 2013

AbstractPulsing cyclohexane or methanol‐water solutions of chlorobenzene and fluorobenzene with the Nd laser at 265 mμ (half‐height width 30 nsec) gives rise to intermediates, absorbing in the 290–300 mμ region, attributed to the corresponding triplet states. The decay of the triplet states is roughly first order with rate constants of (2.1 ± 0.1) × 106 sec−1 and (1.5 ± 0.1) × 106 sec−1 respectively. No transient absorption was observed with bromo‐ and iodobenzene under the same conditions. Solutions of the two latter compounds containing KI or KBr show the appearance of I−2 or IBr− following laser excitation.
Performance of gadoxetic acid‐enhanced MRI for detecting hepatocellular carcinoma in recipients of living‐related‐liver‐transplantation: Comparison with dynamic multidetector row computed tomography and angiography‐assisted computed tomography
Authors: Kakihara Daisuke , Nishie Akihiro , Harada Noboru , Shirabe Ken , Tajima Tsuyoshi , Asayama Yoshiki , Ishigami Kousei , Nakayama Tomohiro , Takayama Yukihisa , Okamoto Daisuke , Fujita Nobuhiro , Kishimoto Junji , Honda Hiroshi 
Published: November 2013

PurposeTo clarify the diagnostic performance of gadoxetic acid‐enhanced MRI for the detection of hepatocellular carcinoma (HCC) in recipients of living related‐liver transplantation (LRLT).Materials and MethodsThis retrospective study group consisted of 15 patients with 61 HCCs who each underwent multidetector row computed tomography (MDCT), gadoxetic acid‐enhanced MRI, and angiography‐assisted computed tomography (CT) before LRLT. The three modalities were compared for their ability to detect HCC. Two blinded readers independently reviewed the images obtained by each modality for the presence of HCC on a segment‐by‐segment basis using a 5‐point confidence scale. The diagnostic performance of the modalities was evaluated in a receiver operating characteristic (ROC) analysis. The area under the ROC curve (Az), sensitivity, specificity, and accuracy were compared for the three modalities.ResultsNo significant difference in Az, sensitivity, specificity, or accuracy was obtained among gadoxetic acid‐enhanced MRI, MDCT, and angiography‐assisted CT for both readers. For reader 1, the sensitivity (55.6%) and the accuracy (84.7%) of angiography‐assisted CT were significantly higher than those of MDCT (33.3% and 78.0%) (P < 0.05).ConclusionGadoxetic acid‐enhanced MRI has a relatively high diagnostic ability to detect HCC even in recipients of LRLT, equivalent to the abilities of MDCT and angiography‐assisted CT. J. Magn. Reson. Imaging 2014;40:1112–1120. © 2013 Wiley Periodicals, Inc.
Evaluating the dosimetric effect of treatment‐induced changes in virally mediated head and neck cancer patients
Authors: Brown Elizabeth , Owen Rebecca , Mengersen Kerrie , Harden Fiona , Porceddu Sandro 
Published: November 2013

AbstractIntroductionPatients with virally mediated head and neck cancer (VMHNC) often present with advanced nodal disease that is highly radioresponsive as demonstrated by tumour and nodal regression during treatment. The resultant changes may impact on the planned dose distribution and so adversely affect the therapeutic ratio. The aim of this study was to evaluate the dosimetric effect of treatment‐induced anatomical changes in VMHNC patients who had undergone a replan.MethodsThirteen patients with virally mediated oropharyngeal or nasopharyngeal cancer who presented for definitive radiotherapy between 2005 and 2010 and who had a replan generated were investigated. The dosimetric effect of anatomical changes was quantified by comparing dose–volume histograms (DVH) of primary and nodal gross target volumes and organs at risk (OAR), including spinal cord and parotid glands, from the original plan and a comparison plan.ResultsEleven three‐dimensional conformal radiation therapy (3DCRT) and two intensity modulated radiation therapy (IMRT) plans were evaluated. Dose to the spinal cord and brainstem increased by 4.1% and 2.6%, respectively. Mean dose to the parotid glands also increased by 3.5%. In contrast, the dose received by 98% of the primary and nodal gross tumour volumes decreased by 0.15% and 0.3%, respectively, when comparing the initial treatment plan to the comparison plan.ConclusionIn this study, treatment‐induced anatomical changes had the greatest impact on OAR dose with negligible effect on the dose to nodal gross tumour volumes.In the era of IMRT, accounting for treatment‐induced anatomical changes is important as focus is placed on minimizing the acute and long‐term side effects of treatment.
Endoscopic endonasal approach to the maxillary strut: Anatomical review and case series
Authors: Grewal Sanjeet S. , Kurbanov Almaz , Anaizi Amjad , Keller Jeffrey T. , Theodosopoulos Philip V. , Zimmer Lee A. 
Published: November 2013

Objectives/HypothesisThe maxillary strut is the bone that separates the foramen rotundum and superior orbital fissure. Tumors involving the lateral wall of the sphenoid sinus, posterior ethmoid, or posterior maxillary sinus may invade this region. The authors detail the anatomy of the strut and present a case series that emphasizes the importance and utility of this useful landmark during an endoscopic endonasal approach to lesions in this region.Study DesignCadaveric dissections and retrospective case series.MethodsEndoscopic endonasal dissections were performed on six formalin‐fixed cadaver heads. Morphometric analyses of 100 skulls were conducted using CT scans and BrainLab. Four patients underwent procedures that exposed the maxillary strut.ResultsThe maxillary strut was trapezoidal shaped with an average cross‐sectional area of 15.25 ± 0.48 mm2 and average thickness of 4.43 ± 0.10 mm. The maxillary strut was present bilaterally in all skulls examined. Anteroposterior length averaged 4.18 ± 0.15 mm on the right and 3.90 ± 0.14 mm on the left. Our patient series illustrated the clinical utility of the maxillary strut as a landmark during endoscopic approaches to the skull base.ConclusionsAn endoscopic endonasal approach can be used to expose the maxillary strut. Improved understanding of this anatomy is important to achieving success when using this approach for the biopsy or resection of lesions in the lateral sellar compartment, pterygopalatine fossa, and aspects of the middle cranial fossa.Level of EvidenceN/A. Laryngoscope, 124:1739–1743,2014
A continuously variable beam‐diameter, high‐fluence, Q‐switched Nd:YAG laser for tattoo removal: Comparison of the maximum beam diameter to a standard 4‐mm‐diameter treatment beam
Authors: Bernstein Eric F. , Civiok Jennifer M. 
Published: November 2013

BackgroundLaser beam diameter affects the depth of laser penetration. Q‐switched lasers tend to have smaller maximum spot sizes than other dermatologic lasers, making beam diameter a potentially more significant factor in treatment outcomes.ObjectiveTo compare the clinical effect of using the maximum‐size treatment beam available for each delivered fluence during laser tattoo removal to a standard 4‐mm‐diameter treatment beam.MethodThirteen tattoos were treated in 12 subjects using a Q‐switched Nd:YAG laser equipped with a treatment beam diameter that was adjustable in 1 mm increments and a setting that would enable the maximally achievable diameter (“MAX‐ON” setting) with any fluence. Tattoos were randomly bisected and treated on one side with the MAX‐ON setting and on the contralateral side with a standard 4‐mm‐diameter spot (“MAX‐OFF” setting). Photographs were taken 8 weeks following each treatment and each half‐tattoo was evaluated for clearance on a 10‐point scale by physicians blinded to the treatment conditions.ResultsTattoo clearance was greater on the side treated with the MAX‐ON setting in a statistically significant manner following the 1st through 4th treatments, with the MAX‐OFF treatment site approaching the clearance of the MAX‐ON treatment site after the 5th and 6th treatments.ConclusionsThis high‐energy, Q‐switched Nd:YAG laser with a continuously variable spot‐size safely and effectively removes tattoos, with greater removal when using a larger spot‐size. Lasers Surg. Med. 45:621–627, 2013. © 2013 Wiley Periodicals, Inc.
Rolling of cast Al‐SiCp particulate metal matrix composites and strip mechanical properties
Authors: Taha M. A. , EL‐Sabbagh A. M. , Soliman M. , Palkowski H. 
Published: November 2013

AbstractThermomechanical physical simulation is applied to get the optimum hot rolling parameters of aluminium silicon carbide composites. Wrought Al 6061 and 6082 – Silicon carbide particulate (SiCp) metal matrix composite strips are prepared by stir‐casting followed by sequential rolling assisted with intermediate heat treatment to allow crystallization recovery and further processing. SiCp are used in two microgrit grades; namely F500 and F800. The reinforcing particulates are used after surface oxidation and 0.3% Mg is added during melting and stirring for loss substitution. With the pre‐treatments applied, SiCp are successfully inserted in the Al matrix, better wetting between particles and matrix, better particles distribution, less agglomeration and minimized reactions between SiC particles. Thermo‐mechanical simulation as a tool for physical simulation indicates that rolling at 450°C using a rate of 1 s–1 rate represent suitable rolling conditions. Successive hot rolling resulted in decreasing void percent and SiCp agglomeration. Hence, enhanced mechanical properties are achieved.
In vivo evaluation of multi‐echo hybrid PRF/T1 approach for temperature monitoring during breast MR‐guided focused ultrasound surgery treatments
Authors: Todd Nick , Diakite Mahamadou , Payne Allison , Parker Dennis L. 
Published: November 2013

PurposeTo evaluate the precision of in vivo temperature measurements in adipose and glandular breast tissue using a multi‐echo hybrid PRF/T1 pulse sequence.MethodsA high‐bandwidth, multi‐echo hybrid PRF/T1 sequence was developed for monitoring temperature changes simultaneously in fat‐ and water‐based tissues. The multiple echoes were combined with the optimal weightings for magnitude and phase images, allowing for precise measurement of both T1 and the proton resonance frequency (PRF) shift. The sequence was tested during in vivo imaging of 10 healthy volunteers in a breast‐specific MR‐guided focused ultrasound system and also during focused ultrasound heating of excised breast adipose tissue.ResultsThe in vivo results indicated that the sequence can measure PRF temperatures with 1.25 × 1.25 × 3.5 mm resolution, 1.9 s temporal resolution, and 1.0°C temperature precision, and can measure T1 values with 3.75 × 3.75 × 3.5 mm resolution, 3.8 s temporal resolution, and 2.5%–4.8% precision. The excised tissue heating experiments demonstrate the sequence's ability to monitor temperature changes simultaneously in water‐ and fat‐based tissues.ConclusionThe addition of a high‐bandwidth, multi‐echo readout to the hybrid PRF/T1 sequence improves the precision of each measurement, providing a sequence that will be beneficial to several MR‐guided thermal therapies. Magn Reson Med 72:793–799, 2014. © 2013 Wiley Periodicals, Inc.
Radial k‐t SPIRiT: Autocalibrated parallel imaging for generalized phase‐contrast MRI
Authors: Santelli Claudio , Schaeffter Tobias , Kozerke Sebastian 
Published: November 2013

PurposeTo extend SPIRiT to additionally exploit temporal correlations for highly accelerated generalized phase‐contrast MRI and to compare the performance of the proposed radial k‐t SPIRiT method relative to frame‐by‐frame SPIRiT and radial k‐t GRAPPA reconstruction for velocity and turbulence mapping in the aortic arch.Theory and MethodsFree‐breathing navigator‐gated two‐dimensional radial cine imaging with three‐directional multi‐point velocity encoding was implemented and fully sampled data were obtained in the aortic arch of healthy volunteers. Velocities were encoded with three different first gradient moments per axis to permit quantification of mean velocity and turbulent kinetic energy. Velocity and turbulent kinetic energy maps from up to 14‐fold undersampled data were compared for k‐t SPIRiT, frame‐by‐frame SPIRiT, and k‐t GRAPPA relative to the fully sampled reference.ResultsUsing k‐t SPIRiT, improvements in magnitude and velocity reconstruction accuracy were found. Temporally resolved magnitude profiles revealed a reduction in spatial blurring with k‐t SPIRiT compared with frame‐by‐frame SPIRiT and k‐t GRAPPA for all velocity encodings, leading to improved estimates of turbulent kinetic energy.Conclusionk‐t SPIRiT offers improved reconstruction accuracy at high radial undersampling factors and hence facilitates the use of generalized phase‐contrast MRI for routine use. Magn Reson Med 72:1233–1245, 2014. © 2013 Wiley Periodicals, Inc.