987 resultados para bands


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Kiwi are rare and strictly protected birds of iconic status in New Zealand. Yet, perhaps due to their unusual, nocturnal lifestyle, surprisingly little is known about their behaviour or physiology. In the present study, we exploited known correlations between morphology and physiology in the avian inner ear and brainstem to predict the frequency range of best hearing in the North Island brown kiwi. The mechanosensitive hair bundles of the sensory hair cells in the basilar papilla showed the typical change from tall bundles with few stereovilli to short bundles with many stereovilli along the apical-to-basal tonotopic axis. In contrast to most birds, however, the change was considerably less in the basal half of the epithelium. Dendritic lengths in the brainstem nucleus laminaris also showed the typical change along the tonotopic axis. However, as in the basilar papilla, the change was much less pronounced in the presumed high-frequency regions. Together, these morphological data suggest a fovea-like overrepresentation of a narrow high-frequency band in kiwi. Based on known correlations of hair-cell microanatomy and physiological responses in other birds, a specific prediction for the frequency representation along the basilar papilla of the kiwi was derived. The predicted overrepresentation of approximately 4-6 kHz matches potentially salient frequency bands of kiwi vocalisations and may thus be an adaptation to a nocturnal lifestyle in which auditory communication plays a dominant role.

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Three thousand liters of water were infiltrated from a 4 m diameter pond to track flow and transport inside fractured carbonates with 20-40 % porosity. Sixteen time-lapse 3D Ground Penetrating Radar (GPR) surveys with repetition intervals between 2 hrs and 5 days monitored the spreading of the water bulb in the subsurface. Based on local travel time shifts between repeated GPR survey pairs, localized changes of volumetric water content can be related to the processes of wetting, saturation and drainage. Deformation bands consisting of thin sub vertical sheets of crushed grains reduce the magnitude of water content changes but enhance flow in sheet parallel direction. This causes an earlier break through across a stratigraphic boundary compared to porous limestone without deformation bands. This experiment shows how time-lapse 3D GPR or 4D GPR can non-invasively track ongoing flow processes in rock-volumes of over 100 m3.

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The mineral series triplite-zwieselite with theoretical formula (Mn2+)2(PO4)(F)-(Fe2+)2(PO4)(F) from the El Criolo granitic pegmatite, located in the Eastern Pampean Ranges of Córdoba Province, was studied using electron microprobe, thermogravimetry, and Raman and infrared spectroscopy. The analysis of the mineral provided a formula of (Fe1.00, Mn0.85, Ca0.08, Mg0.06)∑2.00(PO4)1.00(F0.80, OH0.20)∑1.00. An intense Raman band at 981 cm−1 with a shoulder at 977 cm−1 is assigned to the ν1 symmetric stretching mode. The observation of two bands for the phosphate symmetric stretching mode offers support for the concept that the phosphate units in the structure of triplite-zwieselite are not equivalent. Low-intensity Raman bands at 1012, 1036, 1071, 1087, and 1127 cm−1 are assigned to the ν3 antisymmetric stretching modes. A set of Raman bands at 572, 604, 639, and 684 cm−1 are attributed to the ν4 out-of-plane bending modes. A single intense Raman band is found at 3508 cm−1 and is assigned to the stretching vibration of hydroxyl units. Infrared bands are observed at 3018, 3125, and 3358 cm−1 and are attributed to water stretching vibrations. Supplemental materials are available for this article. Go to the publisher's online edition of Spectroscopy Letters to view the supplemental file.

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Gilalite is a copper silicate mineral with a general formula of Cu5Si6O17 · 7H2O. The mineral is often found in association with another copper silicate mineral, apachite, Cu9Si10O29 · 11H2O. Raman and infrared spectroscopy have been used to characterize the molecular structure of gilalite. The structure of the mineral shows disorder, which is reflected in the difficulty of obtaining quality Raman spectra. Raman spectroscopy clearly shows the absence of OH units in the gilalite structure. Intense Raman bands are observed at 1066, 1083, and 1160 cm−1. The Raman band at 853 cm−1 is assigned to the –SiO3 symmetrical stretching vibration and the low-intensity Raman bands at 914, 953, and 964 cm−1 may be ascribed to the antisymmetric SiO stretching vibrations. An intense Raman band at 673 cm−1 with a shoulder at 663 cm−1 is assigned to the ν4 Si-O-Si bending modes. Raman spectroscopy complemented with infrared spectroscopy enabled a better understanding of the molecular structure of gilalite.

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This project was designed to support high school teachers in participating schools to work with students whose literacy proficiency in key elements of the literacy component of the Year 9 LaN tests were in the low bands. -- p. 5.

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A series of Pt(II) diimine complexes bearing benzothiazolylfluorenyl (BTZ-F8), diphenylaminofluorenyl (NPh2- F8), or naphthalimidylfluorenyl (NI-F8) motifs on the bipyridyl or acetylide ligands (Pt-4−Pt-8), (i.e., {4,4′-bis[7-R1-F8-(≡)n-]bpy}Pt(7- R2-F8- ≡ -)2, where F8 = 9,9′-di(2-ethylhexyl)fluorene, bpy = 2,2′- bipyridine, Pt-4: R1 = R2 = BTZ, n = 0; Pt-5: R1 = BTZ, R2 = NI, n = 0; Pt-6: R1 = R2 = BTZ, n = 1; Pt-7: R1 = BTZ, R2 = NPh2, n = 1; Pt- 8: R1 = NPh2, R2 = BTZ, n = 1) were synthesized. Their ground-state and excited-state properties and reverse saturable absorption performances were systematically investigated. The influence of these motifs on the photophysics of the complexes was investigated by spectroscopic methods and simulated by time-dependent density functional theory (TDDFT). The intense absorption bands below 410 nm for these complexes is assigned to predominantly 1π,π* transitions localized on either the bipyridine or the acetylide ligands; while the broad low-energy absorption bands between 420 and 575 nm are attributed to essentially 1MLCT (metal-to-ligand charge transfer)/ 1LLCT (ligand-to-ligand charge transfer) transitions, likely mixed with some 1ILCT (intraligand charge transfer) transition for Pt-4−Pt-7, and predominantly 1ILCT transition admixing with minor 1MLCT/1LLCT characters for Pt-8. The different substituents on the acetylide and bipyridyl ligands, and the degrees of π-conjugation in the bipyridyl ligand influence both the 1π,π* and charge transfer transitions pronouncedly. All complexes are emissive at room temperature. Upon excitation at their respective absorption band maxima, Pt-4, Pt-6, and Pt-8 exhibit acetylide ligand localized 1π,π* fluorescence and 3MLCT/3LLCT phosphorescence in CH2Cl2, while Pt-5 manifests 1ILCT fluorescence and 3ILCT phosphorescence. However, only 1LLCT fluorescence was observed for Pt-7 at room temperature. The nanosecond transient absorption study was carried out for Pt-4−Pt-8 in CH3CN. Except for Pt-7 that contains NPh2 at the acetylide ligands, Pt-4−Pt-6 and Pt-8 all exhibit weak to moderate excited-state absorption in the visible spectral region. Reverse saturable absorption (RSA) of these complexes was demonstrated at 532 nm using 4.1 ns laser pulses in a 2 mm cuvette. The strength of RSA follows this trend: Pt-4 > Pt-5 > Pt-7 > Pt-6 > Pt-8. Incorporation of electron-donating substituent NPh2 on the bipyridyl ligand significantly decreases the RSA, while shorter π-conjugation in the bipyridyl ligand increases the RSA. Therefore, the substituent at either the acetylide ligands or the bipyridyl ligand could affect the singlet and triplet excited-state characteristics significantly, which strongly influences the RSA efficiency.

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The hippocampus is an anatomically distinct region of the medial temporal lobe that plays a critical role in the formation of declarative memories. Here we show that a computer simulation of simple compartmental cells organized with basic hippocampal connectivity is capable of producing stimulus intensity sensitive wide-band fluctuations of spectral power similar to that seen in real EEG. While previous computational models have been designed to assess the viability of the putative mechanisms of memory storage and retrieval, they have generally been too abstract to allow comparison with empirical data. Furthermore, while the anatomical connectivity and organization of the hippocampus is well defined, many questions regarding the mechanisms that mediate large-scale synaptic integration remain unanswered. For this reason we focus less on the specifics of changing synaptic weights and more on the population dynamics. Spectral power in four distinct frequency bands were derived from simulated field potentials of the computational model and found to depend on the intensity of a random input. The majority of power occurred in the lowest frequency band (3-6 Hz) and was greatest to the lowest intensity stimulus condition (1% maximal stimulus). In contrast, higher frequency bands ranging from 7-45 Hz show an increase in power directly related with an increase in stimulus intensity. This trend continues up to a stimulus level of 15% to 20% of the maximal input, above which power falls dramatically. These results suggest that the relative power of intrinsic network oscillations are dependent upon the level of activation and that above threshold levels all frequencies are damped, perhaps due to over activation of inhibitory interneurons.

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Current approaches for purifying plasmids from bacterial production systems exploit the physiochemical properties of nucleic acids in non-specific capture systems. In this study, an affinity system for plasmid DNA (pDNA) purification has been developed utilizing the interaction between the lac operon (lacO) sequence contained in the pDNA and a 64mer synthetic peptide representing the DNA-binding domain of the lac repressor protein, LacI. Two plasmids were evaluated, the native pUC19 and pUC19 with dual lacO3/lacOs operators (pUC19lacO3/lacOs), where the lacOs operator is perfectly symmetrical. The DNA-protein affinity interaction was evaluated by surface plasmon resonance using a Biacore system. The affinity capture of DNA in a chromatography system was evaluated using LacI peptide that had been immobilized to Streamline™ adsorbent. The KD-values for double stranded DNA (dsDNA) fragments containing lacO1 and lacO3 and lacOs and lacO3 were 5.7 ± 0.3 × 10 -11 M and 4.1 ± 0.2 × 10-11 M respectively, which compare favorably with literature reports of 5 × 10-10 - 1 × 10-9 M for native laCO1 and 1-1.2 × 10-10 M for lacO1 in a saline buffer. Densitometric analysis of the gel bands from the affinity chromatography run clearly showed a significant preference for capture of the supercoiled fraction from the feed pDNA sample. The results indicate the feasibility of the affinity approach for pDNA capture and purification using native protein-DNA interaction.

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Isolated and purified organosolv eucalyptus wood lignin was depolymerized at different temperatures with and without mesostructured silica catalysts (i.e., SBA-15, MCM-41, ZrO2-SBA-15 and ZrO2-MCM-41). It was found that at 300 oC for 1 h with a solid/liquid ratio of 0.0175/1 (w/v), the SBA-15 catalyst with high acidity gave the highest syringol yield of 23.0% in a methanol/water mixture (50/50, wt/wt). Doping with ZrO2 over these catalysts did not increase syringol yield, but increased the total amount of solid residue. Gas chromatography-mass spectrometry (GC-MS) also identified other main phenolic compounds such as 1-(4-hydroxy-3,5-dimethoxyphenyl)-ethanone, 1,2-benzenediol, and 4-hydroxy-3,5-dimethoxy-benzaldehyde. Analysis of the lignin residues with Fourier transform-Infrared spectroscopy (FT-IR) indicated decreases in the absorption bands intensities of OH group, C-O stretching of syringyl ring and aromatic C-H deformation of syringol unit, and an increase in band intensities associated with the guaiacyl ring, confirming the type of products formed.

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Background: Malaria rapid diagnostic tests (RDTs) are appropriate for case management, but persistent antigenaemia is a concern for HRP2-detecting RDTs in endemic areas. It has been suggested that pan-pLDH test bands on combination RDTs could be used to distinguish persistent antigenaemia from active Plasmodium falciparum infection, however this assumes all active infections produce positive results on both bands of RDTs, an assertion that has not been demonstrated. Methods: In this study, data generated during the WHO-FIND product testing programme for malaria RDTs was reviewed to investigate the reactivity of individual test bands against P. falciparum in 18 combination RDTs. Each product was tested against multiple wild-type P. falciparum only samples. Antigen levels were measured by quantitative ELISA for HRP2, pLDH and aldolase. Results: When tested against P. falciparum samples at 200 parasites/μL, 92% of RDTs were positive; 57% of these on both the P. falciparum and pan bands, while 43% were positive on the P. falciparum band only. There was a relationship between antigen concentration and band positivity; ≥4 ng/mL of HRP2 produced positive results in more than 95% of P. falciparum bands, while ≥45 ng/mL of pLDH was required for at least 90% of pan bands to be positive. Conclusions: In active P. falciparum infections it is common for combination RDTs to return a positive HRP2 band combined with a negative pan-pLDH band, and when both bands are positive, often the pan band is faint. Thus active infections could be missed if the presence of a HRP2 band in the absence of a pan band is interpreted as being caused solely by persistent antigenaemia.

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Peggy Shaw’s RUFF, (USA 2013) and Queensland Theatre Company’s collaboration with Queensland University of Technology, Total Dik!, (Australia 2013) overtly and evocatively draw on an aestheticized use of the cinematic techniques and technologies of Chroma Key to reveal the tensions in their production and add layers to their performances. In doing so they offer invaluable insight where the filmic and theatrical approaches overlap. This paper draws on Eckersall, Grehan and Scheer’s New Media Dramaturgy (2014) to reposition the frame as a contribution to intermedial theatre and performance practices in light of increasing convergence between seemingly disparate discourses. In RUFF, the scenic environment replicates a chroma-key ‘studio’ which facilitates the reconstruction of memory displaced after a stroke. RUFF uses the screen and projections to recall crooners, lounge singers, movie stars, rock and roll bands, and an eclectic line of eccentric family members living inside Shaw. While the show pays tribute to those who have kept her company across decades of theatrical performance, use of non-composited chroma-key technique as a theatrical device and the work’s taciturn revelation of the production process during performance, play a central role in its exploration of the juxtaposition between its reconstructed form and content. In contrast Total Dik! uses real-time green screen compositing during performance as a scenic device. Actors manipulate scale models, refocus cameras and generate scenes within scenes in the construction of the work’s examination of an isolated Dictator. The ‘studio’ is again replicated as a site for (re)construction, only in this case Total Dik! actively seeks to reveal the process of production as the performance plays out. Building on RUFF, and other works such as By the Way, Meet Vera Stark, (2012) and Hotel Modern’s God’s Beard (2012), this work blends a convergence of mobile technologies, models, and green screen capture to explore aspects of transmedia storytelling in a theatrical environment (Jenkins, 2009, 2013). When a green screen is placed on stage, it reads at once as metaphor and challenge to the language of theatre. It becomes, or rather acts, as a ‘sign’ that alludes to the nature of the reconstructed, recomposited, manipulated and controlled. In RUFF and in Total Dik!, it is also a place where as a mode of production and subsequent reveal, it adds weight to performance. These works are informed by Auslander (1999) and Giesenkam (2007) and speak to and echo Lehmann’s Postdramatic Theatre (2006). This paper’s consideration of the integration of studio technique and live performance as a dynamic approach to multi-layered theatrical production develops our understanding of their combinatory use in a live performance environment.

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The road from Bali’s international airport to the island’s most renowned tourist area, Kuta Beach, leads past a number of establishments claiming affiliation to reggae music and Rastafarianism in large, appropriately coloured billboards. A sign outside a tee shirt shop bears the words RASTA MANIA within a green, yellow and red border, and a stick figure caricaturing negritude, the logo of this clothing label. In the window display hangs a tee shirt, and upon it Bob Marley’s wizened face. His lips pinch a cone-shaped spliff, and he squints behind a veil of airbrushed smoke. A leanto sign on the sidewalk outside Apache Bar announce REGGAE BANDS NIGHTLY. This barn of coconut wood and thatch nestles behind Wendy’s Ice Cream Parlour and Chi Chi’s Mexican Bar. Its timber walls emulate a rustic, spaghetti Western aesthetic and are adorned with portraits of native Americans. In addition to the reggae bands, nightly, Apache bar unites young Japanese women with local ‘guides’.2

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Raman and infrared spectra of the uranyl mineral phurcalite, Ca2(UO2)3O2(PO4)2⋅7H2O, from Red Canyon, Utah, USA, were studied and tentatively interpreted. Observed bands were assigned to the stretching and bending vibrations of (UO2)2+ and (PO4)3− units and to the stretching and bending vibrations and libration modes of water molecules. Approximate lengths of U–O in (UO2)2+ and O–H⋯O hydrogen bond lengths were inferred from observed stretching vibrations. The presence of structurally nonequivalent U6+ and P5+ was inferred from the number of corresponding stretching bands of (UO2)2+ and (PO4)3− units observed in the Raman and infrared spectra..

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The mineral coquimbite has been analysed using a range of techniques including SEM with EDX, thermal analytical techniques and Raman and infrared spectroscopy. The mineral originated from the Javier Ortega mine, Lucanas Province, Peru. The chemical formula was determined as ðFe3þ 1:37; Al0:63ÞP2:00ðSO4Þ3 9H2O. Thermal analysis showed a total mass loss of 73.4% on heating to 1000 C. A mass loss of 30.43% at 641.4 C is attributed to the loss of SO3. Observed Raman and infrared bands were assigned to the stretching and bending vibrations of sulphate tetrahedra, aluminium oxide/hydroxide octahedra, water molecules and hydroxyl ions. The Raman spectrum shows well resolved bands at 2994, 3176, 3327, 3422 and 3580 cm 1 attributed to water stretching vibrations. Vibrational spectroscopy combined with thermal analysis provides insight into the structure of coquimbite.

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We have studied the boron containing mineral ezcurrite Na4B10O17·7H2O using electron microscopy and vibrational spectroscopy. Both tetrahedral and trigonal boron units are observed. The nominal resolution of the Raman spectrometer is of the order of 2 cm−1 and as such is sufficient enough to identify separate bands for the stretching bands of the two boron isotopes. The Raman band at 1037 cm−1 is assigned to BO stretching vibration. Raman bands at 1129, 1163, 1193 cm−1 are attributed to BO stretching vibration of the tetrahedral units. The Raman band at 947 cm−1 is attributed to the antisymmetric stretching modes of tetrahedral boron. The sharp Raman peak at 1037 cm−1 is from the 11-B component such a mode, then it should have a smaller 10-B satellite near (1.03) × (1037) = 1048 cm−1, and indeed a small peak at 1048 is observed. The broad Raman bands at 3186, 3329, 3431, 3509, 3547 and 3576 cm−1 are assigned to water stretching vibrations. Broad infrared bands at 3170, 3322, 3419, 3450, 3493, 3542, 3577 and 3597 cm−1 are also assigned to water stretching vibrations. Infrared bands at 1330, 1352, 1389, 1407, 1421 and 1457 cm−1 are assigned to the antisymmetric stretching vibrations of trigonal boron. The observation of so many bands suggests that there is considerable variation in the structure of ezcurrite. Infrared bands at 1634, 1646 and 1681 cm−1 are assigned to water bending modes. The number of water bending modes is in harmony with the number of water stretching vibrations.