Drakematthews4209

Some hummingbirds produce unique high-frequency vocalizations. It remains unknown whether these hummingbirds can hear these sounds, which are produced at frequencies beyond the range at which most birds can hear. Here, we show behavioral and neural evidence of high-frequency hearing in a hummingbird, the Ecuadorian Hillstar (Oreotrochilus chimborazo). In the field, hummingbirds responded to playback of high-frequency song with changes in body posture and approaching behavior. We assessed neural activation by inducing ZENK expression in the brain auditory areas in response to the high-frequency song. We found higher ZENK expression in the auditory regions of hummingbirds exposed to the high-frequency song compared to controls, while no difference was observed in the hippocampus between groups. The behavioral and neural responses show that this hummingbird can hear sounds at high frequencies. This is the first evidence of the use of high-frequency vocalizations and high-frequency hearing in conspecific communication in a bird.Development of p-type transparent conducting materials has been a challenging issue. The known p-type transparent conductors unsatisfy both of high transparency and high conductivity nor exhibit superconductivity. Here, we report on epitaxial synthesis, excellent p-type transparent conductivity, and two-dimensional superconductivity of Li1-x NbO2. The LiNbO2 epitaxial films with NbO2 sheets parallel to (111) plane of cubic MgAl2O4 substrates were stabilized by heating amorphous films. The hole doping associated with Li+ ion deintercalation triggered superconductivity below 4.2 kelvin. Optical measurements revealed that the averaged transmittance to the visible light of ~100-nanometer-thick Li1-x NbO2 was ~77%, despite the large number of hole carriers exceeding 1022 per cubic centimeter. These results indicate that Li1-x NbO2 is a previously unknown p-type transparent superconductor, in which strongly correlated electrons at the largely isolated Nb 4d z2 band play an important role for the high transparency.The peptide hormone oxytocin modulates socioemotional behavior and sexual reproduction via the centrally expressed oxytocin receptor (OTR) across several species. Here, we report the crystal structure of human OTR in complex with retosiban, a nonpeptidic antagonist developed as an oral drug for the prevention of preterm labor. Our structure reveals insights into the detailed interactions between the G protein-coupled receptor (GPCR) and an OTR-selective antagonist. The observation of an extrahelical cholesterol molecule, binding in an unexpected location between helices IV and V, provides a structural rationale for its allosteric effect and critical influence on OTR function. Furthermore, our structure in combination with experimental data allows the identification of a conserved neurohypophyseal receptor-specific coordination site for Mg2+ that acts as potent, positive allosteric modulator for agonist binding. Together, these results further our molecular understanding of the oxytocin/vasopressin receptor family and will facilitate structure-guided development of new therapeutics.Allosteric communication within proteins is a hallmark of biochemical signaling, but the dynamic transmission pathways remain poorly characterized. We combined NMR spectroscopy and surface plasmon resonance to reveal these pathways and quantify their energetics in the glucocorticoid receptor, a transcriptional regulator controlling development, metabolism, and immune response. Our results delineate a dynamic communication network of residues linking the ligand-binding pocket to the activation function-2 interface, where helix 12, a switch for transcriptional activation, exhibits ligand- and coregulator-dependent dynamics coupled to graded activation. The allosteric free energy responds to variations in ligand structure subtle changes gradually tune allostery while preserving the transmission pathway, whereas substitution of the entire pharmacophore leads to divergent allosteric control by apparently rewiring the communication network. Our results provide key insights that should aid in the design of mechanistically differentiated ligands.A previously unknown gas-solid interacted power generation is developed using triboelectric effect. We designed an adhesive, gas-tight, and self-healing supramolecular polysiloxane-dimethylglyoxime-based polyurethane (PDPU) porous elastomer based on segmented oxime-carbamate-urea. It is an intrinsically triboelectric negative material with trapped air within closed voids, exhibiting ultrahigh static surface potential and excellent compressibility. This porous PDPU generates electricity from interactions between the trapped air and the elastomeric matrix under periodical compression. The positively charged trapped air (or other gas) dominates the tribo-electrification with PDPU, inducing electron transfer from gas to the solid polymer for electricity generation. The self-healable elastomer renders gas-solid interacted triboelectric nanogenerator, GS-TENG, with high stretchability (~1200%). selleck chemical The inherently adhesive surface enables adherance to other substrates, allowing mechanical energy harvesting from deformations such as bending, twisting, and stretching. GS-TENG promises a freestanding wearable functional tactile skin for self-powered sensing of touch pressure, human motions, and Parkinsonian gait.Metasurfaces with unparalleled controllability of light have shown great potential to revolutionize conventional optics. However, they mainly require external light excitation, which makes it difficult to fully integrate them on-chip. On the other hand, integrated photonics enables packing optical components densely on a chip, but it has limited free-space light controllability. Here, by dressing metasurfaces onto waveguides, we molded guided waves into any desired free-space modes to achieve complex free-space functions, such as out-of-plane beam deflection and focusing. This metasurface also breaks the degeneracy of clockwise- and counterclockwise-propagating whispering gallery modes in an active microring resonator, leading to on-chip direct orbital angular momentum lasing. Our study shows a viable route toward complete control of light across integrated photonics and free-space platforms and paves a way for creating multifunctional photonic integrated devices with agile access to free space, which enables a plethora of applications in communications, remote sensing, displays, etc.