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X-ray photon correlation spectroscopy (XPCS) holds strong promise for observing atomic-scale dynamics in materials, both at equilibrium and during non-equilibrium transitions. Here an in situ XPCS study of the relaxor ferroelectric PbMg1/3Nb2/3O3 (PMN) is reported. A weak applied AC electric field generates strong response in the speckle of the diffuse scattering from the polar nanodomains, which is captured using the two-time correlation function. Correlated motions of the Bragg peak are also observed, which indicate dynamic tilting of the illuminated volume. This tilting quantitatively accounts for the observed two-time speckle correlations. The magnitude of the tilting would not be expected solely from the modest applied field, since PMN is an electrostrictive material with no linear strain response to the field. A model is developed based on non-uniform static charging of the illuminated surface spot by the incident micrometre-scale X-ray beam and the electrostrictive material response to the combination of static and dynamic fields. The model qualitatively explains the direction and magnitude of the observed tilting, and predicts that X-ray-induced piezoresponse could be an important factor in correctly interpreting results from XPCS and nanodiffraction studies of other insulating materials under applied AC field or varying X-ray illumination. [ABSTRACT FROM AUTHOR]

Despite the successes achieved so far with the Global Programme to Eliminate Lymphatic Filariasis, there is still an appreciable number of lymphatic filarial patients who need alternative treatment and morbidity management strategies. The unresponsiveness of some cohorts to the drugs used in the mass drug administration program is currently raising a lot of questions and this needs urgent attention. Natural medicinal plants have a long‐standing history of being effective against most disease conditions. Countries such as India have been able to integrate their natural plant remedies into the treatment of lymphatic filarial conditions, and the results are overwhelmingly positive. Components of Azadirachta indica A. Juss, Parkia biglobosa, Adansonia digitata, and Ocimum spp have been shown to have anti‐inflammatory, anticancerous, and antimicrobial activities in animal models. Therefore, this review calls for attention toward the use of natural plant components as an alternate treatment against lymphatic filariasis to help reduce the World Health Organization's burden of providing drugs for people in need of treatment every year. [ABSTRACT FROM AUTHOR]

A new copper catalysed desymmetrisation reaction of bisalkynyl ferrocenecarboxylic acids using (R,R)‐Ph‐Pybox results in the first asymmetric synthesis of planar chiral pseudo‐isocoumarins in up to 64 % enantiomeric excess and up to 99 % yield with complete regioselectivity. Tri‐functionalised planar chiral ferrocenes are synthesised in five steps from commercially available materials, without the need for traditional directing group chemistry via an easily diversified route exploiting the double Sonogashira coupling reaction. The absolute configuration of the chiral heterocycles is proven by chemical correlation and circular dichroism spectroscopy giving the asymmetric reaction synthetic utility and opening the way for the rational extension of this method to produce bioactive isocoumarin‐fused ferrocene derivatives. [ABSTRACT FROM AUTHOR]

The new asymmetric click CuAAC reaction is used for the first time to induce asymmetry in planar chiral compounds. There are only three classes of stereogenicity (atom‐centred, axial and planar), and these results are therefore of fundamental importance as well as practical significance, providing access to chiral ferrocenes at near enantiopurity. Here, we report asymmetric induction (AI) and kinetic resolution (KR) studies on a novel library of prochiral 1,2,3‐trisubstituted bis‐alkynylferrocenes, obtained by diiodination, derivatisation (including reduction and etherification), double Sonogashira coupling and finally transesterification, azidation or silylation. Desymmetrisation using chiral ligands to modify the CuAAC reaction proceeds in up to 60 % yield and >99.5 % ee, yielding planar chiral ferrocenes. The absolute configuration of two of the preferred products was proved by chemical correlation and related to the entire series by circular dichroism spectroscopy (CD). [ABSTRACT FROM AUTHOR]

Covalently linked multiple calixarenes are valued in supramolecular chemistry. This work reports an easy and versatile synthetic route to covalently linked double and triple calix[4]arene and calix[6]arenes by a novel DMF‐controlled selective alkylation of a convenient and readily available upper‐rim dimethylaminomethyl‐substituted tetrahydroxy and hexahydroxy calix[4]arene and ‐[6]arenes. Synthetic routes to upper‐rim functionalised redox active disulfide‐linked double‐, tetra‐ and peptidohybrid‐calixarenes employing either redox chemistry (CH2SH) or thiolates (CH2S−) are also opened up from the same key starting material. Double and triple calix[4]‐ and calix[6]arenes are easily accessible by a novel selective alkylation reaction employing n‐propyl mesylate in DMF. Disulfide‐linked double‐ and peptidohybrid‐calixarenes and a tetra‐calixarene, formed either redox chemistry (CH2SH) or thiolate (CH2S−) addition, are also described. [ABSTRACT FROM AUTHOR]

We have screened small molecule libraries specifically for inhibitors that target WWP2, an E3 ubiquitin ligase associated with tumour outgrowth and spread. Selected hits demonstrated dose‐dependent WWP2 inhibition, low micromolar IC50 values, and inhibition of PTEN substrate‐specific ubiquitination. Binding to WWP2 was confirmed by ligand‐based NMR spectroscopy. Furthermore, we used a combination of STD NMR, the recently developed DEEP‐STD NMR approach, and docking calculations, to propose for the first time an NMR‐validated 3D molecular model of a WWP2‐inhibitor complex. These first generation WWP2 inhibitors provide a molecular framework for informing organic synthetic approaches to improve activity and selectivity. HTS screen and DEEP‐STD NMR validation of a 3D structural model was used to discover a new class of WWP2 ubiquitin ligase inhibitors. [ABSTRACT FROM AUTHOR]

In anticipation of the increased use of coherent X‐ray methods and the need to upgrade beamlines to match improved source quality, here the coherence properties of the X‐rays delivered by beamline 12ID‐D at the Advanced Photon Source have been characterized. The measured X‐ray divergence, beam size, brightness and coherent flux at energies up to 26 keV are compared with the calculated values from the undulator source, and the effects of beamline optics such as a mirror, monochromator and compound refractive lenses are evaluated. Diffraction patterns from slits as a function of slit width are analyzed using wave propagation theory to obtain the beam divergence and thus coherence length. Imaging of the source using a compound refractive lens was found to be the most accurate method for determining the vertical divergence. While the brightness and coherent flux obtained without a monochromator (`pink beam') agree well with those calculated for the source, those measured with the monochromator were a factor of three to six lower than the source, primarily because of vertical divergence introduced by the monochromator. The methods described herein should be widely applicable for measuring the X‐ray coherence properties of synchrotron beamlines. [ABSTRACT FROM AUTHOR]

An efficient two-step synthesis of structurally and functionally diverse thiophenol- and (cyclo)alkyl-derived malonic acid half thioesters (MAHTs) and phenol-derived malonic acid half oxyesters (MAHOs) has been achieved using cheap, readily available and easily handled starting materials. The synthesis of the MAHTs and MAHOs (the majority of which have not been previously reported) is readily scalable to afford gram quantities of product. In a hydrogen →deuterium exchange, an interesting stereoelectronic effect was observed when different aryl groups were incorporated. Significant changes in the rates of hydrogen →deuterium exchange and levels of isotope incorporation were observed. By way of example, using [2H]methanol and 4-bromophenol-derived MAHO afforded only 14 % [2H]-incorporation (9 min, k=31) whereas the corresponding 4-bromothiophenol-derived MAHT afforded 97 % [2H]-incorporation (9 min, k=208). In a benchmark procedure and comprehensive DFT study, 54 ester and thioester configurations and conformations were characterized. In the MAHT series, a sulfur-containing molecular orbital provides a path for increased delocalisation of electron density into the enol that is unavailable in MAHOs. This facilitates keto-enol tautomerisation and consequently enhances the rate and percentage of hydrogen →deuterium exchange. [ABSTRACT FROM AUTHOR]

The effect of organolithium reagent (RLi: R=nBu, iPr, sBu, tBu), solvent (diethyl ether, diethyl ether/THF and MTBE), and stoichiometry on the (–)-sparteine-mediated silylation of 7,8-dipropyltetrathia[7]helicene shows that, unusually, substantially more than 0.5 equivalent of RLi (R=iPr, sBu, tBu) and a large excess of (–)-sparteine (R=nBu, sBu) is often needed to achieve substantial conversions and good ee values. With nBuLi, however, just one equivalent of the organolithium reagent is sufficient to obtain high conversions. Our best results were obtained using the convenient tBuLi/(–)-sparteine adduct with which the need for a high (–)-sparteine/RLi ratio can be avoided. Single- and double-kinetic resolution (KR) procedures give enantiopure samples of 2- trimethylsilyl- and 2,13-di(trimethylsilyl)-7,8-dipropyltetrathia[ 7]helicene and two-step double-KR combining (–)-sparteine/sBuLi and chiral formamides affords the synthetically valuable 2-formyl-7,8-dipropyltetrathia[7]helicene. This is the first use of (–)-sparteine for the enantioselective lithiation of helicenes and the first report of tBuLi outperforming sBuLi in a (–)-sparteine-mediated procedure. [ABSTRACT FROM AUTHOR]

Asymmetric formylation of aromatic compounds is virtually unexplored. We report the synthesis and evaluation of a library including 20 new chiral formamides in the kinetic resolution of 7,8-dipropyltetrathia[7]helicene, affording the corresponding formyl- or diformylhelicenes in up to 73 % ee, making enantiopure compounds available by recrystallisation. With the N, N-disubstituted formamides used in this study, the best enantioselectivity has been achieved with R1= iPr, R2=Me, R3=H, R4=1-naphthyl or its 1-pyrenyl equivalent. [ABSTRACT FROM AUTHOR]

Utilizing 'off the shelf' commercially available, cheap, small synthetic molecules that mimic the efficient mediation of important bioreactions utilized by Nature is not only highly sought after but also currently highly topical. This paper details our preliminary efforts at developing a unique base- and metal-free phase-transfer-mediated malonic acid thioester (MAHT) 'activation protocol' that efficiently generates (±)-β-thioesters. Our bioinspired aldol process is exceptionally mild, conducted under near neutral pH reaction conditions, does not require an inert, oxygen-free atmosphere or anhydrous reaction conditions and is highly atom-economic. Exemplifying the utility of our protocol, the synthesis of an array of structurally and functionally diverse (±)-β-hydroxy thioesters equipped with highly prized functionality, i.e., chlorine, bromine, fluorine, nitrile and nitro groups, is reported, as is the diastereoselective potential of this important reaction. [ABSTRACT FROM AUTHOR]

Background Within Australian hospitals, cardiac and respiratory arrests result in a resuscitation attempt unless the patient is documented as not for resuscitation. Aim To examine the consistency of policies and documentation for withholding in-hospital resuscitation across health services. Method An observational, qualitative review of hospital policy and documentation was conducted in June 2013 in three public and two private sector hospitals in metropolitan Melbourne. Not for resuscitation ( NFR) forms were evaluated for physical characteristics, content, authorisation and decision-making. Hospital policies were coded for alerts, definition of futility and burden of treatment and management of discussions and dissent. Results There was a lack of standardisation, with each site using its own unique NFR form and accompanying site-specific policies. Differences were found in who could authorise the decision, what was included on the form, the role of patients and families, and how discussions were managed and dissent resolved. Futility and burden of treatment were not defined independently. These inconsistencies across sites contribute to a lack of clarity regarding the decision to withhold resuscitation, and have implications for staff employed across multiple hospitals. Conclusions NFR forms should be reviewed and standardised so as to be clear, uniform and consistent with the legislative framework. We propose a two-stage process of documentation. Stage 1 facilitates discussion of patient-specific goals of care and consideration of limitations of treatment. Stage 2 serves to communicate a NFR order. Decisions to withhold resuscitation are inherently complex but could be aided by separating the decision-making process from the communication of the decision, resulting in improved end-of-life care. [ABSTRACT FROM AUTHOR]

Disubstituted (cyclohexadienyl)iron(1+) complex 2b is prepared by an improved route that starts from 1,2-dimethoxycyclohexa-1,4-diene 3. In five steps, the synthesis of 2b is achieved by complexation with Fe(CO)5, hydride abstraction, hydrolysis, addition of EtO2CCH2ZrBr, and reaction with HBF4. In the presence of dimethyl sulfide, the reaction of 2b with 2-[CH2N(CH2CH=CH2)2]-functionalized diarylcuprate reagent 7 gave the 5α-arylcyclohexadiene complex 1b in 88 % yield. A DFT study compared diarylzinc and diarylcuprate reagents containing chelating CH2NMe2 substituents. [ABSTRACT FROM AUTHOR]

The Hard X-ray Nanoprobe Beamline (or Nanoprobe Beamline) is an X-ray microscopy facility incorporating diffraction, fluorescence and full-field imaging capabilities designed and operated by the Center for Nanoscale Materials and the Advanced Photon Source at Sector 26 of the Advanced Photon Source at Argonne National Laboratory. This facility was constructed to probe the nanoscale structure of biological, environmental and material sciences samples. The beamline provides intense focused X-rays to the Hard X-ray Nanoprobe (or Nanoprobe) which incorporates Fresnel zone plate optics and a precision laser sensing and control system. The beamline operates over X-ray energies from 3 to 30 keV, enabling studies of most elements in the periodic table, with a particular emphasis on imaging transition metals. [ABSTRACT FROM AUTHOR]

Aryllithium reagents react with tricarbonyl(η5-1,4-dimethoxycyclohexadienyl)iron hexafluorophosphate to give η4 products, which are converted into a series of (1-arylcyclohexadienyl)iron(1+) complexes with H, CHO, CH2OAc, and CH(OAc)2 on the arene, ortho to the point of attachment to the dienyl ligand. The structures of these complexes have been compared by X-ray crystallography. Correlations between spectroscopic and structural data indicate that the crystallographically defined conformations are also significant in the interpretation of the pathways of nucleophile addition in solution. Reactions with nucleophiles are influenced by the conformational properties of the 1-aryl substituent, and examples of ω addition and a new intramolecular ipso addition relative to the arene have been characterised. Intermolecular ipso addition has been used to synthesise the alkaloid mesembrine in which 3,4-dimethoxy electron-donating substituents flatten the arylcyclohexadienyl portion and facilitate the ipso pathway. Electron-withdrawing formyl substituents cause the arene to adopt a more perpendicular conformation, and a through-space interaction between CHO and the exo face of the cationic dienyliron complex activates the aldehyde for reaction with (PhC≡C)2CuLi, generating an alkoxide that forms a spirocyclic ether by intramolecular reaction with the aryl-substituted terminus of the dienyl ligand. Full spectroscopic assignments of the (1-arylcyclohexadienyl)iron(1+) complexes are reported and correlated with structural data from crystallography to show that the complexes fall into two groups in terms of the relationship between the dihedral angle of the arene and the dienyl systems and the weighted means for ν(CO) in their infrared spectra. The relationship between this structural data, the distribution of positive charge on the dienyliron complex, and the regioselectivity of nucleophile addition explains how the correct choice of substitution patterns influences the selectivity between ipso and ω reactivity in 1,1-iterative strategies that use (1-arylcyclohexadienyl)iron(1+) complexes as key building blocks in synthetic routes to the galanthamine and crinine subclasses of the Amaryllidaceae alkaloids. [ABSTRACT FROM AUTHOR]

The article features studies on organic and organometallic chemistry. A powerful tool in synthetic chemistry is provided by directed metallation because of the intrinsic regioselectivity of the process. The attachment of a chiral diamine at a formyl group to dessymetrize the 1,4-cyclohexadiene 8 is used by a sequential synthesis of (-)-γ-lycorane. Several iterations representing gradual improvements have been passed through by water-soluble metathesis catalysts.

Discusses several issues related to organic and organometallic chemistry. Structure of carboranes; Information on triprotonation; Activation of alkynes and allenes.

In situ synchrotron X-ray scattering was used to observe both the growth of PbTiO3 films by metal-organic chemical vapour deposition and the behaviour of the ferroelectric phase transition as a function of film thickness. The dependences of growth mode and deposition rate on gas flows and substrate temperature were determined by homoepitaxial growth studies on thick films (>50 nm). These studies facilitated the growth of thin coherently strained PbTiO3 films on SrTiO3 (001) substrates, with thicknesses ranging from 2 to 42 nm. Experiments on the ferroelectric phase transition as a function of film thickness were carried out in these films under controlled mechanical and electrical boundary conditions. [ABSTRACT FROM AUTHOR]

Classical Mendelian experiments were conducted to determine the genetics and inheritance of quinclorac and acetolactate synthase (ALS)-inhibitor resistance in a biotype of Galium spurium. Plants were screened with the formulated product of either quinclorac or the ALS-inhibitor, thifensulfuron, at the field dose of 125 or 6 g active ingredient (a.i.) ha-1 respectively. Segregation in the F2 generation indicated that quinclorac resistance was a single, recessive nuclear trait, based on a 1:3 segregation ratio [resistant : susceptible (R:S)]. Resistance to ALS inhibitors was due to a single, dominant nuclear trait, segregating in the F2 generation in a 3:1 ratio (R:S). The genetic models were confirmed by herbicide screens of F1 and backcrosses between the F1 and the S parent. F2 plants that survived quinclorac treatment set seed and the resulting F3 progeny were screened with either herbicide. Quinclorac-treated F3 plants segregated in a 1:0 ratio (R:S), hence F2 progenitors were homozygous for quinclorac resistance. In contrast, F3 progeny segregated into three ratios: 1:0, 3:1 and 0:1 (R:S) in response to ALS-inhibitor treatment. This segregation pattern indicates that their F2 parents were either homozygous or heterozygous for ALS-inhibitor resistance. Therefore, there were clearly two distinct resistance mechanisms encoded by two genes that were not tightly linked as demonstrated by segregation patterns of the F3. [ABSTRACT FROM AUTHOR]

Provides an overview of studies about organometallic, inorganic and organic chemistry. "Screening Catalysts for Reduction of Carbon Dioxide"; "Alkene Isomerization Claisen Rearrangement Sequences"; "Elimination of Sulphur from Heterocycles"; "Transannular Diels-Alder Reactions."

Presents highlights of several studies on chemistry as of September 2003. Significance of the linkages between vanadosilicate clusters; Molecular strategies to study the genome; Overview of the intramolecular cyanoborylation of alkynes.

Discusses several studies on organometallic chemistry, inorganic chemistry and organic chemistry released in 2002 and 2003. "Asymmetric Coupling of Alkynes to Aldehydes," by Miller, Huand and Jamison, published in the "Journal of American Chemical Society"; "TiS[sub2] Nanotubes for Hydrogen Storage," by J. Chen, S-L Li, Z-L Lao Y-T Shen and C-X Cui; "Asymmetric Amplification in Autocatalysis," by K. Tsukiyama and K Soai, et al, published in "Tetrahedron Asymmetry."

Although it is widely believed that visual cues play an important part in person perception, the experimental literature is inconclusive. Two issues in particular remain unresolved: whether visual information affects participants in conversations in the same way it affects observers; and how the accuracy, quality, and confidence of impressions are related to one another. The purpose of the present experiment was to explore both issues, by incorporating participants and observers in one design, and examining all three aspects of impressions at once. Participants were video-recorded in pairs, either face-to-face or over an audio-only link, and the recordings were subsequently played to observers under conditions of sound and vision, vision only, or sound only. There were several differences in confidence estimates between participants and observers, but there was no evidence for either accuracy or quality effects. In addition, there was no evidence that observers were affected by whether or not they had visual information, or that face-to-face and audio participants differed in the impressions they created. It is concluded that visual cues play a smaller part in impression formation than has generally been supposed. [ABSTRACT FROM AUTHOR]

The article examines the relationship of inter-group understanding and inter-party friction in industries in Great Britain. Inter-Group Understanding is a measure which appropriates the word 'understanding' for a particular use and which is based on the perceptions of both parties. In this usage 'understanding' simply means how well one group can estimate the position of another group, and Inter-Group Understanding refers to the systematic interaction of these estimates for both groups. Attitudes and attributed attitudes are drawn from mutually meaningful topics, reflecting the interests of both groups, and, by appropriate comparison, attribution errors are derived and combined into a single score which thus summarises the nature and extent of Inter-Group Understanding. In order to investigate the nature of the relationship between Inter-Group Understanding and friction it is obviously necessary to collect information on both attitudes and behaviour from the same firms. It was also to be expected that the forms of friction would be related to size; increased frequencies of events occurring in the larger firms.

This article presents a research which aims to trace the variation of measures of intergroup characteristics and to examine its relationship to size of the organization. It also aims to establish the background beliefs and perceptions of a representative sample drawn from both sides of industry and to derive suitable and reliable measures of inter-group characteristics. The conclusion derived from the findings of research is that the approach via understanding is more useful, and the intergroup measure more sensitive, compared to a straightforward concentration on basic attitudes. The interpretations of the size effect are equally fruitful. Basic attitudes do not reveal much with respect to size. In contrast to basic attitudes Inter-Group Understanding shows that different sizes of firms are characterized by different kinds of understanding. In small and large firms understanding is inaccurate, but in small firms this inaccuracy is indulgent, in large it is stereotyped.

Laboratory studies have shown that the amounts of glutathione (GSH) and cysteine are higher in grass species that are moderately tolerant, such as wheat (Triticum aestivum L.,cv. Fredrick), and moderately susceptible, such as barley (Hordeum vulgare L., cv. Legér) and triticale (cv. OAC Trillium), to fenoxaprop-ethyl (FE) than in species that are very susceptible to the herbicide, such as oat (Avena sativa L., cv. OAC Woodstock), wild oat (Avena fatim L.), yellow foxtail (Setaria glatica (L.) Beauv.), large crabgrass (Digitaria sangitinalis (L.) Scop.) and barnyard grass (Echinochloa crus-galli (L.) P.B.). The safener, fenchlorazole-ethyl (FCE) was found to increase and decrease, respectively, the amounts of GSH and cysteine in the moderately tolerant and moderately susceptible species but had no effect on the susceptible species. It is suggested that in the moderately tolerant and moderately susceptible species, especially following FCE treatment, more GSH is available to detoxify the herbicide. Glutathione-5-tranferase activity (GST) for FE was found to be very low in all of the species tested. In vitro experiments at physio-logical pH, demonstrated that FE may conjugate with GSH nonenzymatically. Therefore, it is suggested that nonenzymatic conjugation of fenoxaprop-ethyl with glutathione may be an important mechanism for tolerance of some grasses to this herbicide. [ABSTRACT FROM AUTHOR]

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Electron impact mass spectra of the trimethylsilyl derivatives of a series of flavonoid aglycones and chalcones are reported. The spectra show prominent ions arising from fragmentation of the trimethylsilyl (TMS) groups. Inter-actions between adjacent TMS groups, and between TMS groups in the 3- or 5-position (6′-position for the chalcones) and the C-ring carbonyl, yield structurally significant ions. Few fragments associated with the retro-Diels-Alder cleavage of the C-ring characteristic of the underivatized compounds, are observed. The TMS derivatives thus provide complementary information for the identification of flavonoid aglycones and chalcones in biological systems. [ABSTRACT FROM AUTHOR]

Copyright of European Journal of Social Psychology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Argyle & Dean (1965) predicted that, as the distance increased between a confederate who stared continuously and a naive subject, so the naive subject would increasingly return the confederate's gaze into the eyes. Their findings were held to support the prediction, but Stephenson & Rutter (1970) offered an alternative explanation. They showed that, in the Argyle & Dean situation, observers are increasingly likely with increasing distance to record as gaze directed at the eyes, gaze which is actually directed away from the eyes. In the present experiment, pairs of naive subjects took up positions equidistant from a one-way screen behind which two cameras were located. Each pair held a 5 min. conversation, nine pairs at 2 ft. apart, nine at 6 ft. and nine at 10 ft. The interactions were recorded on videotape, and four observers subsequently scored Looking and Speech from the recordings for each subject independently. By means of zoom lens photography and a ‘split-screen’ recording technique, it was ensured that any relationship between visual behaviour and distance could not be an artifact of observer performance. The results indicated that, while neither the duration of individuals' Looking nor the number of Looks were significantly affected by distance, the two measures of mutual Looking, namely the duration of eye-contact, and mutual focus (the proportion of a pair's Looking which results in eye-contact), both increased with distance. [ABSTRACT FROM AUTHOR]