Correction to: Transmission of the frequency components of the vibrational signal of the glassy-winged sharpshooter, Homalodisca vitripennis, within and between grapevines.

Unfortunately, Fig. 3 was incorrectly published in the original publication. The correct version of Fig. 3 is updated here.

Transmission of the frequency components of the vibrational signal of the glassy-winged sharpshooter, Homalodisca vitripennis, within and between grapevines.

The agricultural pest, Homalodisca vitripennis, relies on vibrational communication through plants for species identification, location, and courtship. Their vibrational signal exhibits a dominant frequency between 80 and 120 Hz, with higher frequency, lower intensity harmonics occurring approximately every 100 Hz. However, previous research revealed that not all harmonics are recorded in every signal. Therefore, how the female H. vitripennis vibrational signal changes as it travels through the plant was investigated. Results confirmed that transmission was a bending wave, with decreased signal intensity for increasing distance from the source; moreover, at distances of 50 cm, higher frequencies traveled faster than lower frequencies, suggesting that dispersion of H. vitripennis signal components may enable signaling partners to encode distance. Finally, H. vitripennis generates no detectable airborne signal (pressure wave), yet their low vibrational frequency components are detectable in neighboring plants as a result of leaf-to-air-to-leaf propagation. For instance, with isolated key female signal frequencies, 100 Hz was detected at a 10 cm gap between leaves, whereas 600 Hz was detectable only with a 0.1 cm gap. Together, these results highlight the complexity of vibration propagation in plants and suggest the possibility of the animals using the harmonic content to determine distance to the signaling H. vitripennis source.

"Pipe Organ" Inspired Air-Coupled Ultrasonic Transducers With Broader Bandwidth.

Piezoelectric micromachined ultrasonic transducers (PMUTs) are used to receive and transmit ultrasonic signals in industrial and biomedical applications. This type of transducer can be miniaturized and integrated with electronic systems since each element is small and the power requirements are low. The bandwidth of the PMUT may be narrow in some conventional designs; however, it is possible to apply modified structures to enhance this. This paper presents a methodology for improving the bandwidth of air-coupled PMUTs without sensitivity loss by connecting a number of resonating pipes of various lengths to a cavity. A prototype piezoelectric diaphragm ultrasonic transducer is presented to prove the theory. This novel device was fabricated by additive manufacturing (3-D printing), and consists of a polyvinylidene fluoride thin film over a stereolithography designed backplate. The backplate design is inspired by a pipe organ musical instrument, where the resonant frequency (pitch) of each pipe is mainly determined by its length. The -6-dB bandwidth of the "pipe organ" air-coupled transducer is 55.7% and 58.5% in transmitting and receiving modes, respectively, which is ~5 times wider than a custom-built standard device.