DNA barcoding is the use of short DNA sequences (~650 bp) of the standard segment of the genome for large scale species identification. The Consortium for the Barcode of Life (CBOL) plant-working group recommended the 2-locus combination of rbcL and matK as the standard plant barcode. These two regions of chloroplast DNA were chosen due to efficient recovery of quality sequences and high levels...

Recent molecular studies indicate that the Pyropialanceolata species complex on the west coast of North America is more speciose than previously thought. Based on extensive rbcL gene sequencing of representative specimens we recognize seven species in the complex, three of which are newly described: Pyropiamontereyensis sp. nov., Pyropiacolumbiensis sp. nov., and Pyropiaprotolanceolata sp. nov....

Many sharks, skates, and rays (elasmobranchs) are highly threatened by the activities of commercial fisheries, a clear understanding their distributions, diversity, abundance can guide protective measures. However, surveying monitoring elasmobranch species be invasive or resource-intensive, utilization non-invasive environmental DNA-based methods may overcome these problems. Here, we studied sp...

Unlike most batoid fishes, electric rays neither oscillate nor undulate their body disc to generate thrust. Instead they use body-caudal-fin (BCF) locomotion. In addition, these negatively buoyant rays perform unpowered glides as they sink in the water column. In combination, BCF swimming and unpowered gliding are opposite ends on a spectrum of swimming, and electric rays provide an appropriate...

Aorta eddy is one of the most important parameters of aorta. The incidence of arteriosclerosis can affect the characteristics of eddy current. In this study, we applied trans-esophageal echocardiography to compare aortic vortex parameters between cerebral apoplexy patients (n=102) and normal controls (n=20). Cardiac ultrasound (time resolution=15.4 ± 3.7 milliseconds, 60-80 frames/cardiac cycle...

Soft elastic layers with top and bottom surfaces adhered to rigid bodies are abundant in biological organisms and engineering applications. As the rigid bodies are pulled apart, the stressed layer can exhibit various modes of mechanical instabilities. In cases where the layer's thickness is much smaller than its length and width, the dominant modes that have been studied are the cavitation, int...

Oil pipeline construction and operation in mountainous areas have increased southwestern China, with oil consumption increasing. Such liquid pipelines laid continuously undulate along the terrain, resulting many large elevation difference pipe segments. Serious gas block problems often occur during commissioning process of these due to gas/air accumulation at high point pipe, which causes overp...

Electrospinning is a simple and convenient technique to produce polymer fibers with diameters ranging from several nanometers to a few micrometers. Different types of polymer fibers have been prepared by electrospinning for various applications. Among different post-treatment methods of electrospun polymer fibers, the annealing process plays a critical role in controlling the fiber properties. ...

RF undulators, suggested long time ago, has the advantage of fast dynamic control of polarization, undulator strength and wavelength. However, RF undulators require very strong RF fields in order to produce radiation of the same order as conventional static devices. Very high power RF energy confined inside a waveguide or a cavity can provide the necessary RF fields to undulate the electron bea...