bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation of 14C‐labelled dimethylsilane‐1,1‐diol
Authors: Cella J. A. , Carpenter J. C. 
Published: October 2006

AbstractThe preparation of 14C‐labelled dimethylsilane‐1, 1‐diol in two steps from 14C‐labelled diphenyldimethylsilane is described. Aluminum chloride catalyzed protodesilylation of diphenyldimethylsilane with HCl in dichloromethane or dimethyldichlorosilane at 0–5°C affords labelled dimethyldichlorosilane which is hydrolyzed in the presence of triethylamine to afford the title compound in 45–60% yield.
Synthesis of a [13CO2H]‐labelled bilirubin
Authors: Nogales Daniel F. , Lightner David A. 
Published: October 2006

AbstractBis‐[13CO2H]‐mesobilirubin‐XIIIα was synthesized in 11% overall yield in 10 steps from 99% enriched K13CN. The synthetic methods are adapted to a scale of a few grams to a few milligrams.
Synthesis of isotopically labelled WIN 33377, an anticancer agent related to hycanthone
Authors: Duffin Gordon R. , Ellames George J. , Smith David I. , Wedge Karen J. 
Published: October 2006

Abstract14C labelled and 13C,15N labelled WIN 33377,1, 1‐(2‐diethylaminoethylamino)‐4‐(methanesulphonamidomethyl)thioxanthen‐9‐one, have been prepared by related routes using the known 1‐(2‐diethyl‐aminoethylamino)thioxanthen‐9‐one, 4, as starting material and introducing the label with cyanide prior to further elaboration.
A novel one step approach to small scale labeling of organic compounds with hydrogen isotopes
Authors: Malik Sohail , Kenny Margaret , Doss George , John Varghese 
Published: October 2006

AbstractA rapid method to generate tritium gas for small scale labeling is described. Tritium labelled sodium borohydride is used with cobalt (II) chloride to generate isotopic hydrogen gas. The reaction was carried out in a closed vessel and three different compounds were concurrently labelled. This simple and inexpensive method can be applied to a broad range of molecules and does not require any special set up.
Complexation behaviour of tin(II) ion with derivative of p‐aminohippuric acid
Authors: Djurdjevic Predrag , Maksin Tatjana , Veselinovic Dragan 
Published: October 2006

AbstractComplex formation between tin(II) ion and p‐(biscarboxymethyl)‐aminomethyl‐carbamino‐hippuric acid (PAHIDA) in 0.5 M NaClO4 ionic medium at 298 K, was studied by means of u.v. spectrophotometry and glass electrode potentiometric titrations. In the concentration range 0.09 ⩽ [Sn] ⩽ 0.150, 0.5 ⩽ [PAHIDA] ⩽ 3.0 (mmol dm−3) and 1.30 ⩽ pH ⩽ 6.5, mathematical analysis of potentiometric data, with the aid of general least‐squares programme Superquad, indicates the formation of the following complexes and their respective stability constants (log (β ± σ)): [Sn(H2PAHIDA)] (12.98 ± 0.15), [Sn(HPAHIDA)] (9.38 ± 0.05), [Sn(PAHIDA)] (5.74 ± 0.01) and [Sn(OH)PAHIDA] (1.55 ± 0.09) as well as several pure hydrolytic complexes of tin(II).The effect of tin(II)‐PAHIDA complexation on labelling yield of PAHIDA with 99mTcO4− was investigated. The optimum yield (90%) was achieved at PAHIDA to tin(II) concentration ratio 30:1 and pH = 5.5.
Synthesis of a new selective borotritide : [3H]lithium9‐boratabicyclo[3.3.1]nonane. Some applications to the preparation of secondary and primary [3H] alcohols
Authors: Rasset Christine , Rousseau Bernard 
Published: October 2006

Abstract[3H]lithium 9‐boratabicyclo[3.3.1]nonane, at specific activity of 52–55 Ci/mmol, was synthesized by reduction of B‐OMe‐9‐BBN with lithium tritide. Its reducing characteristics were illustrated by the synthesis of [17‐3H] estradiol, [2‐3H] dihydrotetrabenazine and 1‐(hydroxy[3H]methyl)naphtalene, with good radiochemical yields and high specific activities.
Synthesis of mutagenic 2,4‐dinitro‐[7‐14C]benzaldehyde
Authors: Shoji Miki , Mori Masa‐Aki , Sayama Michio , Kozuka Hiroshi , Honda Takashi 
Published: October 2006

Abstract2,4‐Dinitro‐[7‐14C]benzaldehyde (4), a mutagenic substance which may have an unique metabolic activating pathways, was synthesized as a tracer for the detection of adducts of 4 with macromolecules. The preparation was performed in four steps from [7‐14C]toluene to give an overall radiochemical yield of 20% after purifying by TLC. The radiochemical purity was over 98%.
Isolation and preparation of 3H‐tetrandrine
Authors: Huang Xun Yang , Wang Yin , De Lu Zang 
Published: October 2006

AbstractTetrandrine is a bisbenzytehahydroisoquinoline alkaloid. Its structure is very complex and the preparation of labeled derivatives is difficult. We have prepared 3H‐tetrandrine using the tritium gas exposure method.1 This method produces many fragments which make isolation and purification of small quantities difficult. We investigated these fragments of unlabeled d‐tetrandrine and found almost all contain one to several hydroxide groups. Using this information, we designed a two‐step paper chromatography method for isolation and purification of 3H‐Tetrandrine. This method involves the application of a pH 4.7 Na2HPO4‐citric acid buffer to the paper to block the migration of hydroxide group fragments of tetrandrine. 3H‐tetrandrine was successfully with a radiochemical purity of 90%.
Synthesis of the racemate and individual enantiomers of [11C]methylphenidate for studying presynaptic dopaminergic neuron with positron emission tomography
Authors: Ding Y.‐S. , Sugano Y. , Fowler J. S. , Salata C. 
Published: October 2006

AbstractCarbon‐11 labeled dl‐threo‐methylphenidate (methyl‐2‐phenyl‐2‐(2‐piperidyl)acetate, Ritalin), a psychostimulant drug widely used to treat attention deficit hyperactivity disorder, was prepared in two steps: O‐methylation of the N‐protected dl‐threo‐ritalinic acid derivative with [11C]methyl iodide followed by deprotection. The same strategy was applied for the preparation of C‐11 labeled individual enantiomers of threo‐methylphenidate from N‐protected d‐threo‐ or l‐threo‐ritalinic acid. The subsequent C 18 sep‐pak and reverse‐phase HPLC purification resulted in ca. 40% radiochemical yield with a total synthesis time of 40 minutes and an average specific activity of 1.5 Ci/μmole (at EOB).
The radiosynthesis of a new potential glucose transport protein tracer: 3‐[125I]iodophloretin
Authors: Mertens J. , Terriere D. , Boumon R. 
Published: October 2006

AbstractPhloretin (2′,4′,6′‐trihydroxy‐3‐(4‐hydroxyphenyl)‐propiophenone) is a glucose transport (GLUT) blocker acting at the extracellular part of the GLUT protein. Labelling this compound with radioiodine can provide a tracer for elucidating in vitro and in vivo the role of GLUT's in cells showing an increased glucose metabolism. As the inhibition of GLUT by phloretin is supposed to occur at the 2′,4′,6′‐trihydroxyphenyl site, the radioiodine is substituted on the 3‐position of the 4‐hydroxyphenyl group. Direct electrophilic substitution on this position is not possible due to highly activated sites in the trihydroxyphenyl group. 3‐Bromophloretin, the precursor for radioiodination, is prepared using a new method, a saturation substitution followed by the elimination of the unstable bromine atoms. Radioiodinated phloretin is obtained with a labelling yield of 75% by applying Cu+1‐assisted radioiodo for bromo exchange at 140°C. Pure non carrier added tracer results from HPLC separation coupled to a mini‐column preconcentration and recovery (± 70% overall yield).
Investigations on the chemistry of berbanes 15(1) synthesis of the allo‐berbane skeleton labelled with 14C
Authors: Szammer János , Dörnyei Gábor , Szántay Csaba 
Published: October 2006

Abstract[14‐14C]‐allo‐berbane‐14‐ol: (7,8‐methylenedioxy‐14α‐hydroxy‐[14‐14C]‐allo‐berbane, [14‐14C]1 spec, act.: 405 MBq/mM) was synthesized in nine reaction steps from K14CN (overall radioactive yield: 2.8%).
New processes for the synthesis of 2,6‐dichloro‐3‐methylaniline‐Ph‐UL‐14C and methyl 6‐chloroanthranilate‐Ph‐UL‐14C
Authors: McKendry L. H. , Stanga M. A. 
Published: October 2006

AbstractTwo new processes were developed for the synthesis of 2,6‐dichloro‐3‐methylaniline‐Ph‐UL‐14C (1), a key intermediate in the synthesis of a Dow Elanco experimental product presently being considered for commercialization. Both processes afford product in much higher yields than that previously reported in the literature. One of the processes was subsequently applied to the synthesis of methyl 6‐chloroanthranilate‐Ph‐UL‐14C (12), used as an intermediate for a second potential product.
The radiosynthesis of No‐carrier added [1‐11C]allyl alcohol evidence for the formation of a new reducing species: Lithium aluminium hydride — vinylmagnesium bromide
Authors: Lasne Marie‐Claire , Moreau Bernard , Cairon Philippe , Barré Louisa 
Published: October 2006

AbstractLithium aluminium hydride in the presence of vinylmagnesium bromide (1:1 molar ratio) affords a potent reagent for the reduction of acrylic acid to allyl alcohol (ratio of allyl alcohol to 1‐propanol: 3:2). This reducing mixture has allowed the preparation of nocarrier added [1‐11C]allyl alcohol with a 25% yield (decay corrected at the end of radionuclide production, overall synthesis time including GC: 40 min) in a one step procedure from [11C]carbon dioxide (C‐11: t1/2:20.4 min). [1‐11C] 1‐propanol was obtained in parallel with a 6.5% yield.
Synthesis of tritium labeled renin inhibitor ditekiren
Authors: Hsi Richard S. P. , Stolle Wayne T. , Bundy Gordon L. 
Published: October 2006

AbstractIn the search for a radioactive form of the peptidomimetic renin inhibitor, ditekiren, with a metabolically suitable radiolabel for conducting drug disposition studies, we prepared [3H]ditekiren with tritium labels in the N‐methyl‐histidine moiety and in the leu‐val alcohol transition‐state insert. [His‐3H]ditekiren was obtained by first introducing two iodine substituents into the N‐methyl‐histidine moiety of the parent drug, followed by catalytic hydrodehalogenation with tritium gas. Administration of this labeled drug to monkeys, however, resulted in prolonged retention of radioactivity in the test animals, even though little or no tritiated water was detected in urine. This suggested in vivo production of a labeled fragment from the drug, e.g., N‐methyl‐[3H]histidine, which became incorporated into the endogenous amino acid pool. These results, together with similar earlier findings after administration of [3H]ditekiren labeled in the proline moiety of the drug, led us to synthesize [3H]ditekiren labeled in the “unnatural” leu‐val alcohol (LVA) portion of the molecule. [LVA‐3H]ditekiren was obtained by first oxidizing the parent drug to produce an LVA‐keto analog, which was then reduced with sodium borotritide to give a mixture of tritium labeled ditekiren and its LVA‐epimer. The two epimeric labeled materials were separated and purified by means of preparative high performance liquid chromatography (HPLC). The tritium label in [LVA‐3H]ditekiren was found to be metabolically suitable for conducting drug disposition studies, with no liability for tritiated water production or prolonged retention of radioactivity in tissues of test animals.
Synthesis of Z‐ and E‐[2,3‐2H2] and [2,3‐3H2]‐1,1‐dichloro‐2,3‐ diphenylcyclopropane (2H‐ and 3H‐analog II and its trans isomer)
Authors: Day Billy W. , Jonnalagadda Sastry S. 
Published: October 2006

Abstract2H and 3H labeled Z‐ and E‐1,1‐dichloro‐2,3‐diphenylcyclopropane (1 and 2) were synthesized starting from NaB2H4 and NaB3H4 reduction of benzil. The resulting glycols were transformed to the 1,2‐labeled Z‐ and E‐stilbenes by thermolysis of their cyclic thionocarbonates in trimethylphosphite. The stilbenes were reacted with phase transfer‐generated dichlorocarbene to form the title compounds. The dideuterio isomers were separated by fractional crystallization in yields of 60 and 48%. Each was greater than 99 % geometrically and 98 % isotopically pure. The ditritio isomers were separated by C‐18 JPLC. The radiochemical yields, on a molar basis using benzil as the limiting reagent, were 42 % and 23 %, each with specific activity of 88.5 mCi/mmol and radiochemical purity of > 95%.
Synthesis of N‐tert‐butyl‐α‐(4‐[18F]fluorophenyl)‐nitrone ([18F]FPBN) for in vivo detection of free radicals
Authors: Bormans G. , Kilbourn M. R. 
Published: October 2006

AbstractWe have synthesized the fluorine‐18 labeled derivative of N‐tert‐butyl‐α‐phenylnitrone (PBN), a free radical spin trapping agent widely used with electron spin resonance (ESR). N‐tert‐Butyl‐α‐(4‐[18F]fluorophenyl)‐nitrone ([18F]FPBN) could be prepared with low radiochemical yield (3% decay corrected) by the direct aromatic nucleophilic substitution of N‐tert‐butyl‐α‐(4‐nitrophenyl)nitrone with [18F]fluoride. An alternate two step synthesis route consisted of the nucleophilic [18F]fluoride substitution of 4‐N, N, N‐trimethylammoniumbenzaldehyde triflate to yield 4‐[18F]fluorobenzaldehyde, which was distilled into a vial containing N‐tert‐butyl‐hydroxylamine in 2N NaOH. 4‐[18F]Fluorobenzaldehyde readily reacted with the hydroxylamine to form [18F]FPBN. [18F]FPBN was obtained in overall decay corrected yields of 24% in a total synthesis time < 45 min. and was suitable for further applications in in vivo studies of free radicals.
Radiosynthesis of a chloroacetanilide herbicide ([phenyl‐4‐3H] acetochlor) and a dichloroacetamide safener for herbicides ([2, 2‐dimethyl‐3H]R‐29148)
Authors: Latli Bachir , Casida John E. 
Published: October 2006

Abstract2‐Chloro‐N‐(ethoxymethyl)‐N‐(2‐ethyl‐6‐methylphenyl)acetamide (the chloroacetanilide herbicide acetochlor) and 3‐(dichloroacetyl)‐ 2,2,5‐trimethyl‐1,3‐oxazolidine (the dichloroacetamide safener R‐ 29148) are required at high specific activity for studies on their metabolism and mode of action. [phenyl‐4‐3H]Acetochlor was obtained at 22 Ci/mmol in 71% yield by reductive dehalogenation of iodoacetochlor with tritium gas in ethanol in the presence of palladium on carbon and triethylamine. [2,2‐dimethyl‐3H]R‐29148 was prepared at 15 Ci/mmol by treating acetone and 1‐amino‐2‐propanol in pentane with two equivalents of NaOH in tritiated water (i.e. hydroxide ion‐catalyzed enolization of acetone) followed by dichloroacetyl chloride.
Synthesis and E.I.M.S. fragmentation analysis of [1,3‐15N2] xanthine and [1,3‐15N2] caffeine
Authors: Kenani A. , Bernier J‐L. , Henichart J‐P. 
Published: October 2006

AbstractHPLC and mass spectrometry can be used to isolate and identify all metabolites of caffeine in plasma of patients. The synthesis of [1,3‐15N2] xanthine and [1,3‐ 15N2] caffeine are of interest in the elucidation of mass spectrometry fragmentation pathways and the unambiguous determination of metabolites, especially uric acid which exists as a natural constituent of human plasma.
Esters of 6‐(4′‐fluorobenzylamino)‐β‐ carboline‐3‐carboxylic acid as potential benzodiazepine imaging agents for P.E.T.
Authors: Elder S. T. , Mach R. H. , Nowak P. A. , Moroney D. A. , Rao A. V. , Ehrenkaufer R. L. E. 
Published: October 2006

AbstractAs potential P.E.T. imaging agents for the benzodiazepine receptor, two fluorine‐ 18 labeled analogues of the β‐carbolines were prepared via N‐ alkylation of the corresponding desbenzyl amine precursors with [18F]fluorobenzyl iodide.
Deuteriodediazoniation: A general method for the replacement of a diazonium group by deuterium
Authors: Wassmundt Frederick W. , Kiesman William F. 
Published: October 2006

AbstractAromatic amino groups are replaced with deuterium via a diazonium salt intermediate. Dimethylformamide‐d7 is the deuterium donor in this mild replacement method that yields aromatic‐d1 products in high isotopic purity. The presence of methyl groups lowers the isotopic purity of the products.
Synthesis of 2β‐carbomethoxy‐3β‐(4‐[76Br]bromophenyl)tropane ([76Br]β‐CBT), a pet tracer for in vivo imaging of the dopamine uptake sites
Authors: Loc'h Christian , Müller Lars , Ottaviani Michèle , Halldin Christer , Farde Lars , Mazière Bernard 
Published: October 2006

Abstract2β‐carbomethoxy‐3β‐(4‐[76Br]bromophenyl)tropane ([76Br]β‐CBT) was prepared either by electrophilic substitution from the tributyl‐stannyl derivative and peracetic acid as oxidant or by nucleophilic substitution from the iodo analogue (β‐CIT) and a Cu+ assisted bromodeiodination exchange. After purification by solid phase extraction and reverse phase HPLC, the chemical and radiochemical purities of [76Br]β‐CBT were > 98% and the specific radioactivity was 20 GBq/μmol. Using the two labelling techniques, the radiochemical yields were 80% and 60%, respectively. From the deshalogeno compound and different oxidizing conditions, the radiolabelling yields were < 5%. In vitro competition and saturation pharmacological studies showed that [76Br]β‐CBT mainly labelled the dopamine transporter and bound to a single population of sites in striatal membranes (Bmax = 6.5 pmol/mg protein) with an apparent dissociation constant of 2.8 nM. Biodistribution and autoradiography studies of the title compound in rats showed that 3 h post injection, the highest concentration in the brain was found in the striata (2.5% ID/g). 24 h post injection, the striatum to cerebellum radioactive concentration ratio was still 17.
Synthesis of 14C‐labelled 6‐hydroxy‐5,7‐dimethyl‐2‐(methylamino)‐4‐(3‐pyridylmethyl)benzothiazole dihydrochloride (14C‐E3040 dihydrochloride)
Authors: Hibi Shigeki , Numata Hirotoshi , Okamoto Yasushi , Takenaka Osamu , Mishima Mannen 
Published: October 2006

Abstract14C‐Labelled 6‐hydroxy‐5,7‐dimethyl‐2‐(methylamino)‐4‐(3‐pyridylmethyl)‐benzothiazole dihydrochloride (14C‐E3040 dihydrochloride), required for a study of the phrmacokinetic profile of E3040, a novel dual inhibitor of 5‐lipoxygenase and thromboxane A2 synthetase, was synthesized in one step using [2‐14C]‐1‐methyl‐2‐thiourea as the labelled starting material. 14C‐E3040 dihydrochloride with a specific activity of 58.0mCi/mmol was prepared in 60% chemical yield(based on thiourea 2).
Synthesis and biodistribution of 14C‐radiolabelled hypocrellin B
Authors: Liu Jixiang , Miller Gerald G. , Huang Liren , Diwu Zhenjun , Lown J. William , Brown Kevin , Moore Ronald B. , Tulip John , McPhee Malcolm S. 
Published: October 2006

AbstractOur research group is currently exploring the use of hypocrellins as potential photosensitizers for photodynamic therapy (PDT). The purpose of this study is to investigate the synthesis and biodistribution of 14C‐labelled Hypocrellin B. Radiolabelled hypocrellin‐B (HB) with the 14C atom incorporated in either or both the 4‐ and 13‐methoxy groups was synthesized with a specific activity of 2.11 mCi per mmol. The purified, 14C‐HB, prototype photodynamic therapy photosensitizer was used to determine the kinetics of uptake in EMT6/Ed cells in monolayer culture, and the kinetics of tumor and tissue distribution in Balb/c mice bearing the EMT6/Ed tumor.
Synthesis of selectively 13C‐labelled benzoic acid for nuclear magnetic resonance spectroscopic measurement of glycine conjugation activity
Authors: Akira Kazuki , Hasegawa Hiroshi , Baba Shigeo 
Published: October 2006

AbstractThe synthesis of [4‐13C]benzoic acid (BA) labelled in a single protonated carbon, for use as a probe to measure glycine conjugation activity by nuclear magnetic resonance (NMR) spectroscopy, has been reported. The labelled compound was prepared by a seven‐step synthetic scheme on a relatively small scale using [2‐13C]acetone as the source of label in overall yield of 16 %. The usefulness of [4‐13C]BA was demonstrated by the NMR spectroscopic monitoring of urinary excretion of [4‐13C]hippuric acid in the rat administered with the labelled BA.
Comparison of two synthetic methods to obtain [18F] N‐(2‐aminoethyl)‐5‐fluoropyridine‐2‐carboxamide, a potential MAO‐B imaging tracer for PET
Authors: Beer H.‐F. , Haeberli M. , Ametamey S. , Schubiger P. A. 
Published: October 2006

AbstractThe compound Ro 19‐6327, N‐(2‐aminoethyl)‐5‐chloropyridine‐2‐carboxamide, is known to inhibit reversibly and site specifically the enzyme monoamine oxidase B (MAO‐B). The 123I‐labelled iodo‐analogue N‐(2‐aminoethyl)‐5‐iodopyridine‐2‐carboxamide (Ro 43‐0463) was investigated successfully in human volunteers by means of SPET (Single Photon Emission Tomography). We developed therefore the synthesis and radiolabelling of the corresponding fluoro‐analogue N‐(2‐aminoethyl)‐5‐fluoropyridine‐2‐carboxamide with 18F in order to carry out PET (Positron Emission Tomography) investigations of MAO‐B related neuropsychiatric diseases. For this purpose two synthetic approaches leading to the electrophilic and the nucleophilic methods of 18F radiolabelling were undertaken. The nucleophilic approach appeared to be superior when factors such as precursor synthesis, beam time, specific activity and radiochemical purity of the product are considered.
Preparation of [11C]‐thymidine and [11C]‐2′‐arabino‐2′‐fluoro‐β‐5‐methyl‐uridine (FMAU) using a hollow fiber membrane bioreactor system
Authors: Hughes Jeffrey A. , Hartman Neil G. , Jay Michael 
Published: October 2006

AbstractA series of hollow fiber membranes containing immobilized enzymes were prepared and used in the synthesis of 11C‐labelled nucleosides. 11C‐Formaldehyde was produced in an alcohol oxidase/catalase bioreactor and circulated through a thymidylate synthase bioreactor with an appropriate substrate to produce the corresponding 11C‐nucleotide. These labelled nucleotides were subsequently dephosphorylated in an alkaline phosphatase bioreactor. The bioreactor approach was amenable to hot‐cell conditions and yielded 11C‐products in higher yield and shorter synthesis times than conventional chemical approaches.
Radiosynthesen biologisch aktiver verbindungen. II Triforine (cela W 524) markiert mit tritum und 14C
Authors: Stiasni Michael , Ost Walter 
Published: October 2006

AbstractAusgehend von Piperazin‐3H (V) wird tritiwmarkiertes Triforine (N, N′‐Bis‐[ 1‐formamido‐2, 2, 2‐trichloröthy1] ‐piperazin ‐ 3H) mit 89 % Ausbeute und einer spezifischen Aktivität von 149 mCi/mNol dargestellt. Bei. der 14C‐Markieruna wird Paraldehyd ‐14C (U) zu Chloral ‐1, 2‐14C ungesetzt und als Chloral ‐ 1, 2‐ 14 C‐formamid isoliert. Dieses wird chloriert und mit piperazin kondensiert. Triforine‐14C entsteht in 25 %‐iger Ausbeute mit einer spezifischem Aktivität von 22 mCi/mMol.
Variable‐oriented and person‐oriented perspectives of analysis: The example of alcohol consumption in adolescence
Authors: von Eye Alexander , Anne Bogat G. , Rhodes Jean E. 
Published: October 2006

ABSTRACTThis article presents person‐oriented and variable‐oriented approaches to data analysis. To illustrate these two approaches and the types of information they provide the researcher, data from 3558 control group youth from the National Cross‐Site Evaluation of High Risk Youth Programs were analysed. The relationship, over time, between parent attitudes and gender as it relates to youth alcohol consumption were examined. Data were analysed and compared using a variable‐oriented approach (repeated measures ANOVA) and a person‐oriented approach (Configural Frequency Analysis). Data analysis demonstrated that variable‐ and person‐oriented approaches provide the researcher with different information that can be complementary. The ANOVA identified an overall trend that accounted for little variance; the CFA explained why this was the case by identifying groups of respondents whose behaviour was different from the overall trend. The implications of these results and the use of both types of approaches are discussed.