171 resultados para Pairing symmetry


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The mining industry is highly suitable for the application of robotics and automation technology since the work is arduous, dangerous and often repetitive. This paper discusses a robust sensing system developed to find and trade the position of the hoist ropes of a dragline. Draglines are large `walking cranes' used in open-pit coal mining to remove the material covering the coal seam. The rope sensing system developed uses two time-of-flight laser scanners. The finding algorithm uses a novel data association and tracking strategy based on pairing rope data.

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During Pavlovian auditory fear conditioning a previously neutral auditory stimulus (CS) gains emotional significance through pairing with a noxious unconditioned stimulus (US). These associations are believed to be formed by way of plasticity at auditory input synapses on principal neurons in the lateral nucleus of the amygdala (LA). One proposed form of cellular plasticity involves structural changes in the number and morphology of dendritic spines...

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During Pavlovian auditory fear conditioning a previously neutral auditory stimulus (CS) gains emotional significance through pairing with a noxious unconditioned stimulus (US). These associations are believed to be formed by way of plasticity at auditory input synapses on principal neurons of the lateral nucleus of the amygdala (LA). While the LA has been implicated as a key brain structure for fear learning, how its network of cellular components performs these operations is not yet known...

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During Pavlovian auditory fear conditioning a previously neutral auditory stimulus (CS) gains emotional significance through pairing with a noxious unconditioned stimulus (US). These associations are believed to be formed by way of plasticity at auditory input synapses on principal neurons in the lateral nucleus of the amygdala (LA). In order to begin to understand how fear memories are stored and processed by synaptic changes in the LA, we have quantified both the entire neural number and the sub-cellular structure of LA principal neurons.We first used stereological cell counting methods on Gimsa or GABA immunostained rat brain. We identified 60,322+/-1408 neurons in the LA unilaterally (n=7). Of these 16,917+/-471 were GABA positive. The intercalated nuclei were excluded from the counts and thus GABA cells are believed to represent GABAergic interneurons. The sub-nuclei of the LA were also independently counted. We then quantified the morphometric properties of in vitro electrophysiologically identified principal neurons of the LA, corrected for shrinkage in xyz planes. The total dendritic length was 9.97+/-2.57mm, with 21+/-4 nodes (n=6). Dendritic spine density was 0.19+/-0.03 spines/um (n=6). Intra-LA axon collaterals had a bouton density of 0.1+/-0.02 boutons/um (n=5). These data begin to reveal the finite cellular and sub-cellular processing capacity of the lateral amygdala, and should facilitate efforts to understand mechanisms of plasticity in LA.

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Phosphohedyphane Ca2Pb3(PO4)3Cl is rare Ca and Pb phosphate mineral that belongs to the apatite supergroup. We have analysed phosphohedyphane using SEM with EDX, and Raman and infrared spectroscopy. The chemical analysis shows the presence of Pb, Ca, P and Cl and the chemical formula is expressed as Ca2Pb3(PO4)3Cl. The very sharp Raman band at 975 cm−1 is assigned to the PO43-ν1 symmetric stretching mode. Raman bands noted at 1073, 1188 and 1226 cm−1 are to the attributed to the PO43-ν3 antisymmetric stretching modes. The two Raman bands at 835 and 812 cm−1 assigned to the AsO43-ν1 symmetric stretching vibration and AsO43-ν3 antisymmetric stretching modes prove the substitution of As for P in the structure of phosphohedyphane. A series of bands at 557, 577 and 595 cm−1 are attributed to the ν4 out of plane bending modes of the PO4 units. The multiplicity of bands in the ν2, ν3 and ν4 spectral regions provides evidence for the loss of symmetry of the phosphate anion in the phosphohedyphane structure. Observed bands were assigned to the stretching and bending vibrations of phosphate tetrahedra. Some Raman bands attributable to OH stretching bands were observed, indicating the presence of water and/or OH units in the structure.

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Burkeite formation is important in saline evaporites and in pipe scales. Burkeite is an anhydrous sulphate-carbonate with an apparent variable anion ratio. Such a formula with two oxyanions lends itself to vibrational spectroscopy. Two symmetric sulphate stretching modes are observed, indicating at least at the molecular level the nonequivalence of the sulphate ions in the burkeite structure. The strong Raman band at 1065 cm−1 is assigned to the carbonate symmetric stretching vibration. The series of Raman bands at 622, 635, 645, and 704 cm−1 are assigned to the ν4 sulphate bending modes. The observation of multiple bands supports the concept of a reduction in symmetry of the sulphate anion from T d to C 3v or even C 2v.

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Sidorenkite is a very rare low-temperature hydrothermal mineral, formed very late in the crystallization of hyperagpaitic pegmatites in a differentiated alkalic massif (Mt. Alluaiv, Kola Peninsula, Russia). Sidorenkite Na3Mn(PO4)(CO3) is a phosphate–carbonate of sodium and manganese. Such a formula with two oxyanions lends itself to vibrational spectroscopy. The sharp Raman band at 959 cm−1 and 1012 cm−1 are assigned to the PO43− stretching modes, whilst the Raman bands at 1044 cm−1 and 1074 cm−1 are attributed to the CO32− stretching modes. It is noted that no Raman bands at around 800 cm−1 for sidorenkite were observed. The infrared spectrum of sidorenkite shows a quite intense band at 868 cm−1 with other resolved component bands at 850 and 862 cm−1. These bands are ascribed to the CO32− out-of-plane bend (ν2) bending mode. The series of Raman bands at 622, 635, 645 and 704 cm−1 are assigned to the ν4 phosphate bending modes. The observation of multiple bands supports the concept of a reduction in symmetry of the carbonate anion from D3h or even C2v.

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The mineral ushkovite has been analyzed using a combination of electron microscopy with EDX and vibrational spectroscopy. Chemical analysis shows the mineral contains P, Mg with very minor Fe. Thus, the formula of the studied ushkovite is Mg32+(PO4)2·8H2O. The Raman spectrum shows an intense band at 953 cm−1 assigned to the ν1 symmetric stretching mode. In the infrared spectra complexity exists with multiple antisymmetric stretching vibrations observed, due to the reduced tetrahedral symmetry. This loss of degeneracy is also reflected in the bending modes. Strong infrared bands around 827 cm−1 are attributed to water librational modes. The Raman spectra of the hydroxyl-stretching region are complex with overlapping broad bands. Hydroxyl stretching vibrations are identified at 2881, 2998, 3107, 3203, 3284 and 3457 cm−1. The wavenumber band at 3457 cm−1 is attributed to the presence of FeOH groups. This complexity is reflected in the water HOH bending modes where a strong infrared band centered around 1653 cm−1 is found. Such a band reflects the strong hydrogen bonding of the water molecules to the phosphate anions in adjacent layers. Spectra show three distinct OH bending bands from strongly hydrogen-bonded, weakly hydrogen bonded water and non-hydrogen bonded water. Vibrational spectroscopy enhances our knowledge of the molecular structure of ushkovite.

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The mineral aluminite has been studied using a number of techniques, including scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDX) and Raman and infrared spectroscopy. Raman spectroscopy identifies multiple sulphate symmetric stretching modes in line with the three sulphate crystallographically different sites. Raman spectroscopy also identifies a low intensity band at 1069 cm−1 which may be attributed to a carbonate symmetric stretching mode, indicating the presence of thaumasite. The observation of multiple bands in this ν4 spectral region offers evidence for the reduction in symmetry of the sulphate anion from Td to C2v or even lower symmetry. The Raman band at 3588 cm−1 is assigned to the OH unit stretching vibration and the broad feature at around 3439 cm−1 to water stretching bands. Water stretching vibrations are observed at 3157, 3294, 3378 and 3439 cm−1. Vibrational spectroscopy enables an assessment of the molecular structure of aluminite to be made.

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We have undertaken a study of the tellurite mineral sonorite using electron microscopy with EDX combined with vibrational spectroscopy. Chemical analysis shows a homogeneous composition, with predominance of Te, Fe, Ce and In with minor amounts of S. Raman spectroscopy has been used to study the mineral sonoraite an examples of group A(XO3), with hydroxyl and water units in the mineral structure. The free tellurite ion has C3v symmetry and four modes, 2A1 and 2E. An intense Raman band at 734 cm−1 is assigned to the ν1 (TeO3)2− symmetric stretching mode. A band at 636 cm−1 is assigned to the ν3 (TeO3)2− antisymmetric stretching mode. Bands at 350 and 373 cm−1 and the two bands at 425 and 438 cm−1 are assigned to the (TeO3)2−ν2 (A1) bending mode and (TeO3)2−ν4 (E) bending modes. The sharp band at 3283 cm−1 assigned to the OH stretching vibration of the OH units is superimposed upon a broader spectral profile with Raman bands at 3215, 3302, 3349 and 3415 cm−1 are attributed to water stretching bands. The techniques of Raman and infrared spectroscopy are excellent for the study of tellurite minerals.

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Purpose There have been only a limited number of studies examining the accommodative response that occurs when the two eyes are provided with disparate accommodative stimuli, and the results from these studies to date have been equivocal. In this study, we therefore aimed to examine the capacity of the visual system to aniso-accommodate by objectively measuring the interocular difference in the accommodation response between fellow dominant and non-dominant eyes under controlled monocular and binocular viewing conditions during short-term exposure to aniso-accommodative stimuli. Methods The accommodative response of each eye of sixteen young isometropic adults (mean age 22 ± 2 years) with normal binocular vision was measured using an open-field autorefractor during a range of testing conditions; monocularly (accommodative demands ranging from 1.32 to 4.55 D) and binocularly while altering the accommodation demand for each eye (aniso-accommodative stimuli ranging from 0.24 to 2.05 D). Results Under monocular viewing conditions, the dominant and non-dominant eyes displayed a highly symmetric accommodative response; mean interocular difference in spherical equivalent 0.01 ± 0.06 D (relative) and 0.22 ± 0.06 D (absolute) (p>0.05). During binocular viewing, the dominant eye displayed a greater accommodative response (0.11 ± 0.34 D relative and 0.24 ± 0.26 D absolute) irrespective of whether the demand of the dominant or non-dominant eye was altered (p = 0.01). Astigmatic power vectors J0 and J45 did not vary between eyes or with increasing accommodation demands under monocular or binocular viewing conditions (p>0.05). Conclusion The dominant and non-dominant eyes of young isometropic individuals display a similar consensual lag of accommodation under both monocular and binocular viewing conditions, with the dominant eye showing a small but significantly greater (by 0.12 to 0.25 D) accommodative response. Evidence of short-term aniso-accommodation in response to asymmetric accommodation demands was not observed.

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MicroRNAs (miRNAs) are small regulatory RNAs produced by Dicer proteins that regulate gene expression in development and adaptive responses to the environment1,​2,​3,​4. In animals, the degree of base pairing between a miRNA and its target messenger RNA seems to determine whether the regulation occurs through cleavage or translation inhibition1. In contrast, the selection of regulatory mechanisms is independent of the degree of mismatch between a plant miRNA and its target transcript5. However, the components and mechanism(s) that determine whether a plant miRNA ultimately regulates its targets by guiding cleavage or translational inhibition are unknown6. Here we show that the form of regulatory action directed by a plant miRNA is determined by DRB2, a DICER-LIKE1 (DCL1) partnering protein. The dependence of DCL1 on DRB1 for miRNA biogenesis is well characterized7,​8,​9, but we show that it is only required for miRNA-guided transcript cleavage. We found that DRB2 determines miRNA-guided translational inhibition and represses DRB1 expression, thereby allowing the active selection of miRNA regulatory action. Furthermore, our results reveal that the core silencing proteins ARGONAUTE1 (AGO1) and SERRATE (SE) are highly regulated by miRNA-guided translational inhibition. DRB2 has been remarkably conserved throughout plant evolution, raising the possibility that translational repression is the ancient form of miRNA-directed gene regulation in plants, and that Dicer partnering proteins, such as human TRBP, might play a similar role in other eukaryotic systems.

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This project originated from both investigation of the musicalisation of theatre and impact of gender upon contemporary physical comedy. Developed as a ‘music first’ proposition, the initial experiment was to blend music and theatre so they were indistinguishable. Musicalising theatre, and theatricalising music. This established a covert intermediality with the potential to work in theatre or music venues. An iterative cycle of writing, performance, and videography over two years in venues ranging from small cafes to Woodford Folk Festival resulted in a full-length performance premiering at Brisbane Powerhouse’s Queensland Cabaret Festival 2015. The soundtrack to the show was recorded as a full-length album at QUT’s Gasworks Studio and released in 2014. It’s become clear that male/female musical comedy acts are an extremely rare pairing. Certain preconceptions about gender and comedy complicate the field; indeed the comic tropes of the double act which the Warmwaters flow around and through. Brian Logan (2011) even poses that “the male-female dynamic militate[s] against comedy”. This performance-led research draws on Comedy Studies to examine three classic formulations of the comic duo as they are manifested at critical incidents in the Warmwaters’ show. These moments are examined in terms of comic functionality and gender, evaluating and potentially reformulating them, whilst working towards a better understanding of the relative scarcity of the male/female musical comedy duo. Prototypes have been performed in various venues, utilising performance as research: cycles in which discoveries made during unpredictable gigs in music venues are captured on video, transcribed, rewritten, then fed back into live performance.

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Barry recently attributed the non-significant relationship between the cultural dimensions of Individualism (IND) and Masculinity (MASC) to a suppression effect of regional differences. Pairing countries on regional proximity, he showed that a strong correlation between these cultural dimensions emerged. However, we point to significant issues with this analysis, including how countries were paired, ordered, and included/excluded, as well as in the cultural meaningfulness of regional proximity. Re-analysis of the data after addressing these issues shows that IND and MASC were not significantly related at a cultural level after controlling for regional proximity, nor after controlling for two other prominent geographic factors: latitude and climate demands. The weight of evidence suggests that IND and MASC are not correlated at a cultural level.

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Multicentric carpotarsal osteolysis (MCTO) is a rare skeletal dysplasia characterized by aggressive osteolysis, particularly affecting the carpal and tarsal bones, and is frequently associated with progressive renal failure. Using exome capture and next-generation sequencing in five unrelated simplex cases of MCTO, we identified previously unreported missense mutations clustering within a 51 base pair region of the single exon of MAFB, validated by Sanger sequencing. A further six unrelated simplex cases with MCTO were also heterozygous for previously unreported mutations within this same region, as were affected members of two families with autosomal-dominant MCTO. MAFB encodes a transcription factor that negatively regulates RANKL-induced osteoclastogenesis and is essential for normal renal development. Identification of this gene paves the way for development of novel therapeutic approaches for this crippling disease and provides insight into normal bone and kidney development.