86,857 research outputs found
ZENK activation in the nidopallium of black-capped chickadees in response to both conspecific and heterospecific calls
No full textNeuronal populations in the songbird nidopallium increase in activity the most to conspecific vocalizations relative to heterospecific songbird vocalizations or artificial stimuli such as tones. Here, we tested whether the difference in neural activity between conspecific and heterospecific vocalizations is due to acoustic differences or to the degree of phylogenetic relatedness of the species producing the vocalizations. To compare differences in neural responses of black-capped chickadees, Poecile atricapillus, to playback conditions we used a known marker for neural activity, ZENK, in the caudal medial nidopallium and caudomedial mesopallium. We used the acoustically complex ‘dee’ notes from chick-a-dee calls, and vocalizations from other heterospecific species similar in duration and spectral features. We tested the vocalizations from three heterospecific species (chestnut-backed chickadees, tufted titmice, and zebra finches), the vocalizations from conspecific individuals (black-capped chickadees), and reversed versions of the latter. There were no significant differences in the amount of expression between any of the groups except in the control condition, which resulted in significantly less neuronal activation. Our results suggest that, in certain cases, neuronal activity is not higher in response to conspecific than in response to heterospecific vocalizations for songbirds, but rather is sensitive to the acoustic features of the signal. Both acoustic features of the calls and the phylogenetic relationship between of the signaler and the receiver interact in the response of the nidopallium.Peer reviewe
Detailed quantification of ZENK protein expression and comparison with ZENK mRNA expression within Cluster N.
No full text<p>A: Expression of ZENK mRNA during night-time covers posterolateral parts of the hyperpallium and underlying mesopallium. In the DNH nucleus, the amount of ZENK mRNA transcripts is decreased. D: Expression of ZENK protein during night-time covers hyperpallial compartments comparable to the expression of ZENK mRNA but decreases in mesopallial portions. Within Cluster N, approximately 56% of neurons show nuclear expression of ZENK protein with highest relative amounts of ZENK-positive nuclei found in the shell surrounding the DNH nucleus. B: Decreased expression of ZENK mRNA and E: protein during day in the whole hyperpallium. Nuclear ZENK protein is found in approximately 22% of Cluster N neurons. Note that, ventral mesopallial (MV) and nidopallial (N) portions show increased ZENK expression on the mRNA and protein level compared to night-time activation patterns. C: Corresponding Nissl-stained section and F: schematic drawing display morphological features and neuroanatomical location of Cluster N within the telencephalon. G: Determination of four subregions within Cluster N defined by morphological boundaries (compare Fig. 3C): DNH nucleus (Fig. 3G, shown in blue); the shell surrounding DNH nucleus (Fig. 3G, shown in green); the remaining hyperpallial Cluster N part (Fig. 3G, shown in yellow); the mesopallial Cluster N part (Fig. 3G, shown in red). Scale bar (for A–G): 250 µm. H: Quantification of percentages of neurons with nuclear expression of ZENK within each subunit. Abbreviations: DNH, dorsal nucleus of the hyperpallium; H, hyperpallium, MD, dorsal mesopallium; MV, ventral hyperpallium; N, nidopallium.</p
Density of ZENK expressing cells in CMM.
No full text<p>Panels A-D depict representative samples of ZENK immunohistochemical labeling in a female exposed to rhythmic song (A), female exposed to arrhythmic song (B), male exposed to rhythmic song (C), and a male exposed to arrhythmic song (D). Panel E depicts a thionin stained adjacent section; the box indicates the area where cells were counted. Panel F depicts the density of ZENK expressing cells between sexes and stimulus types (mean ± standard error). A significant main effect of stimulus type is indicated by the asterisk. A significant main effect of sex is represented by the different lower case letters. Sample sizes are noted within the bars.</p
Partial purification and properties of (S)-norlaudanosoline synthase from Eschscholtzia tenuifolia cell cultures
No full textChromosome Conformation Capture Followed by Genome-Wide Sequencing (Hi-C) in Drosophila Embryos
No full textThis protocol provides specific details on how to perform Hi-C, the genome-wide version of Chromosome Conformation Capture (3C) followed by high-throughput sequencing, in Drosophila embryos. Hi-C provides a genome-wide population-averaged snapshot of the 3D genome organization within nuclei. In Hi-C, formaldehyde-cross-linked chromatin is enzymatically digested using restriction enzymes; digested fragments are biotinylated and subjected to proximity ligation; ligated fragments are purified using streptavidin followed by paired-end sequencing. Hi-C allows the detection of higher order folding structures such as topologically associated domains (TADs) and active/inactive compartments (A/B compartments, respectively). Performing this assay in developing embryos gives the unique opportunity to investigate dynamic chromatin changes when 3D chromatin structure is established in embryogenesis
Contact Call-Driven Zenk Protein Induction and Habituation in Telencephalic Auditory Pathways in the Budgerigar (<i>Melopsittacus Undulatus</i>): Implications For Understanding Vocal Learning Processes
No full textExpression of the immediate early gene protein Zenk (zif 268, egr-1, NGF1A,Krox24) was induced in forebrain auditory nuclei in a vocal learning parrot species, the budgerigar (Melopsittacus undulatus), when the subjects either listened to playbacks of an unfamiliar contact call or to a contact call with which they had been familiarized previously. Auditory nuclei included the Field L complex (L1, L2a, and L3), the neostriatum intermedium pars ventrolateralis (NIVL), the neostriatum adjacent to caudal nucleus basalis (peri-basalis or pBas), an area in the frontal lateral neostriatum (NFl), the supracentral nucleus of the lateral neostriatum (NLs), and the ventromedial hyperstriatum ventrale (HVvm). The latter three nuclei are main sources of auditory input to the vocal system. Two patterns of nuclear staining were induced by contact call stimulation—staining throughout cell nuclei, which was exhibited by at least some neurons in all areas examined except L2a and perinucleolar staining, which was the only kind of staining exhibited in field L2a. The different patterns of Zenk staining indicate that auditory stimulation may regulate the Zenk-dependent transcription of different subsets of genes in different auditory nuclei. The numbers of neurons expressing Zenk staining increased from seven- to 43-fold over control levels when the birds listened to a repeating unfamiliar call. Familiarization of the subjects with the call stimulus, through repeated playbacks, greatly reduced the induction of Zenk expression to the call when it was presented again after an intervening 24-h interval. To determine if neurons exhibiting contact call-driven Zenk expression project to the vocal control system, call stimulation was coupled with dextran amines pathway tracing. The results indicated that tracer injections in the vocal nucleus HVo (oval nucleus of the hyperstriatum ventrale), in fields lateral to HVo and in NLs labeled many Zenk-positive neurons in HVvm, NFl, and NLs. These results support the idea that, in these neurons, egr-1 couples auditory stimulation to the synthesis of proteins involved in either the storing of new perceptual engrams for vocal learning or the processing of novel and/or meaningful acoustic stimuli related to vocal learning or the context in which it occurs.</jats:p
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Frames of ideals of commutative f-rings
No full textIn his study of spectra of f-rings via pointfree topology, Banaschewski [6] considers lattices of l-ideals, radical l-ideals, and saturated l-ideals of a given f-ring A. In each case he shows that the lattice of each of these kinds of ideals is a coherent frame. This means that it is compact, generated by its compact elements, and the meet of any two compact elements is compact. This will form the basis of our main goal to show that the lattice-ordered rings studied in [6] are coherent frames. We conclude the dissertation by revisiting the d-elements of Mart nez and Zenk [30], and characterise them analogously to d-ideals in commutative rings. We extend these characterisa-tions to algebraic frames with FIP. Of necessity, this will require that we reappraise a great deal of Banaschewski's work on pointfree spectra, and that of Mart nez and Zenk on algebraic frames.M. Sc. (Mathematics)Mathematical Science
Analyzing the Genome-Wide Distribution of Histone Marks by CUT&Tag in Drosophila Embryos
No full textCUT&Tag is a method to map the genome-wide distribution of histone modifications and some chromatin-associated proteins. CUT&Tag relies on antibody-targeted chromatin tagmentation and can easily be scaled up or automatized. This protocol provides clear experimental guidelines and helpful considerations when planning and executing CUT&Tag experiments
[Newspaper Clipping: Author Claims Evidence of Second JFK Assassin #1]
No full textNewspaper article titled "Author Claims Evidence of Second JFK Assassin." The article states that author Richard J. Whalen concluded "that there is circumstantial evidence to support the theory of a second assassin in the shooting of President John F. Kennedy.
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