1,064 research outputs found
Domestic dogs (Canis lupus familiaris) are sensitive to the correlation between pitch and timbre in human speech
The perceived pitch of human voices is highly correlated with the fundamental frequency (f0) of the laryngeal source, which is determined largely by the length and mass of the vocal folds. The vocal folds are larger in adult males than in adult females, and men’s voices consequently have a lower pitch than women’s. The length of the supralaryngeal vocal tract (vocal-tract length; VTL) affects the resonant frequencies (formants) of speech which characterize the timbre of the voice. Men’s longer vocal tracts produce lower frequency, and less dispersed, formants than women’s shorter vocal tracts. Pitch and timbre combine to influence the perception of speaker characteristics such as size and age. Together, they can be used to categorize speaker sex with almost perfect accuracy. While it is known that domestic dogs can match a voice to a person of the same sex, there has been no investigation into whether dogs are sensitive to the correlation between pitch and timbre. We recorded a female voice giving three commands (‘Sit’, ‘Lay down’, ‘Come here’), and manipulated the recordings to lower the fundamental frequency (thus lowering pitch), increase simulated VTL (hence affecting timbre), or both (synthesized adult male voice). Dogs responded to the original adult female and synthesized adult male voices equivalently. Their tendency to obey the commands was, however, reduced when either pitch or timbre was manipulated alone. These results suggest that dogs are sensitive to both the pitch and timbre of human voices, and that they learn about the natural covariation of these perceptual attributes
An analytic theory for the resolution attainable using eclipse mapping of exoplanets
We present an analytic theory for the resolution attainable via eclipse
mapping of exoplanets, based on the Fourier components of the brightness
distribution on the planetary disk. We find that the impact parameter
determines which features can and cannot be seen, via the angle of the stellar
edge relative to the axis of the orbit during the eclipse. We estimate the
signal-to-noise ratio as a function of mapping resolution, and use this to
determine the attainable resolution for a given star-planet system. We test
this theory against numerical simulations and find good agreement; in
particular, our predictions for the resolution as a function of stellar edge
angle are accurate to the simulated data to within 10% over a wide range of
angles. Our prediction for the number of spatial modes that can be constrained
given a light curve error is similarly accurate. Finally, we give a list of
exoplanets with the best expected resolution for observations with the NIRISS
SOSS, NIRSpec G395H, and MIRI LRS instruments on JWST.Comment: 11 pages, 9 figures. Submitted to MNRA
Distance-dependent increase in quantum dot photoluminescence by molecular beacons containing dark quenchers
Förster resonance energy transfer is a fluorescence-based technique currently used for numerous biotechnological applications. Although organic fluorophores have traditionally been employed for this method, quantum dots have many unique optical characteristics that make them attractive candidates for this usage. As the present understanding of how quantum dots behave as energy donors is incomplete, it is necessary to conduct further studies towards the physicochemical nature of this phenomenon. Here, we attempt to assess the distance- dependency for quantum dot-based energy transfer by spacing dark quenchers at increasing distances from these nanoparticles’ surfaces.  We describe a surprising finding that quenchers can actually increase the average fluorescence intensity of quantum dot solutions, and we propose a theoretical explanation, which may allow others to more accurately conduct quantitative studies in the future
The rapidly expanding group of RB1-deleted soft tissue tumors : an updated review
The classification of soft tissue tumors has evolved considerably in the last decade, largely due to advances in understanding the pathogenetic basis of many of these, sometimes rare, tumors. Deletion of Retinoblastoma 1 (RB1), a well-known tumor suppressor gene, has been implicated in the tumorigenesis of a particular group of soft tissue neoplasms. This group of so-called "RB1-deleted soft tissue tumors" has been rapidly expanding in recent years, currently consisting of spindle cell/pleomorphic lipoma, atypical spindle cell/pleomorphic lipomatous tumor, pleomorphic liposarcoma, myofibroblastoma, cellular angiofibroma, and acral fibromyxoma. Most of these neoplasms, except pleomorphic liposarcoma, are considered benign entities and are mainly described in the older adult population. This article will review the currently known morphological, immunohistochemical, and molecular features of this heterogeneous group of mesenchymal tumors with an emphasis on differential diagnosis
Turisme, modernització i idiosincrà sia nacional a l’Espanya del segle XX
L’article examina el paper del turisme en la història cultural i polÃtica d’Espanya des del final del segle XIX. Malgrat que s’havien desenvolupat al paÃs les prà ctiques de l’esbarjo modern ja en el vuit-cents, els animadors locals de la indústria turÃstica mostraren la seva decepció davant el reduït nombre d’estrangers que visitaren el territori. Cap al principi del segle XX, el projecte de fomentar una indústria per rebre i atendre el fenomen turÃstic va acabar convertint-se en un component important de l’ampli programa «regeneracionista». Després de la Segona Guerra Mundial, el règim franquista, enfrontant-se a l’ostracisme internacional al qual es va veure sotmès, va conferir al turisme estranger un paper de gran importà ncia per a les relacions internacionals que volia establir. Al llarg de les tres dècades següents, el turisme fou possiblement el bé que més valor tenia per a la dictadura, fins que els mals de la saturació immobilià ria i la corrupció que aquesta va propiciar posaren fi a l’eufòria de l’anomenat «miracle turÃstic» espanyol.This article explores the role of tourism in Spanish cultural and political history in the late nineteenth and twentieth centuries. Although Spain developed moderndomestic leisure practices in the nineteenth century, tourism promoters were dismayedby the small numbers of foreign visitors they received. By the early twentieth century, the project of developing a receptive tourism industry became a major component of a broader program of national «regeneration». After the Second World War, when the Franco dictatorship faced international ostracism, foreign tourism became an important form of international relations. In the subsequent three decades, tourism became arguably the Franco regime’s most important political and economic good until problems of overbuilding and corruption ended the euphoria of Spain’s so-called «tourist miracle».El artÃculo examina el papel del turismo en la historia cultural y polÃtica de España desde fi nales del siglo XIX. Aunque se habÃan desarrollado en el paÃs las prácticas del ocio moderno ya en el siglo XIX, los animadores locales de la industriaturÃstica mostraron su decepción ante el reducido número de extranjeros que visitaban el territorio. Hacia principios del siglo XX, el proyecto de fomentar una industria para recibir y atender el fenómeno turÃstico acabó convirtiéndose en un componenteimportante del amplio programa «regeneracionista». Después de la Segunda Guerra Mundial, el régimen franquista, enfrentándose al ostracismo internacional al que se vio sometido, confirió al turismo extranjero un papel de gran importancia para las relaciones internacionales que ansiaba establecer. A lo largo de las tres décadas siguientes, el turismo fue posiblemente el bien más valioso para la dictadura,hasta que los males de la saturación inmobiliaria y la corrupción que esta propició pusieron fin a la euforia del llamado «milagro turÃstico» español
PtrA is required for coordinate regulation of gene expression during phosphate stress in a marine Synechococcus
Previous microarray analyses have shown a key role for the two-component system PhoBR (SYNW0947, SYNW0948) in the regulation of P transport and metabolism in the marine cyanobacterium Synechococcus sp. WH8102. However, there is some evidence that another regulator, SYNW1019 (PtrA), probably under the control of PhoBR, is involved in the response to P depletion. PtrA is a member of the cAMP receptor protein transcriptional regulator family that shows homology to NtcA, the global nitrogen regulator in cyanobacteria. To define the role of this regulator, we constructed a mutant by insertional inactivation and compared the physiology of wild-type Synechcococcus sp. WH8102 with the ptrA mutant under P-replete and P-stress conditions. In response to P stress the ptrA mutant failed to upregulate phosphatase activity. Microarrays and quantitative RT-PCR indicate that a subset of the Pho regulon is controlled by PtrA, including two phosphatases, a predicted phytase and a gene of unknown function psip1 (SYNW0165), all of which are highly upregulated during P limitation. Electrophoretic mobility shift assays indicate binding of overexpressed PtrA to promoter sequences upstream of the induced genes. This work suggests a two-tiered response to P depletion in this strain, the first being PhoB-dependent induction of high-affinity PO4 transporters, and the second the PtrA-dependent induction of phosphatases for scavenging organic P. The levels of numerous other transcripts are also directly or indirectly influenced by PtrA, including those involved in cell-surface modification, metal uptake, photosynthesis, stress responses and other metabolic processes, which may indicate a wider role for PtrA in cellular regulation in marine picocyanobacteria
- …