Reference gene validation for gene expression studies using quantitative RT-PCR during berry development of ‘Aki Queen’ grapes

In order to understand the gene regulation during berry development and examine the effect of abscisic acid (ABA) on gene expression related to berry maturation, we evaluated the validity of four housekeeping genes, elongation factor 1-α (EF1-α), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), ubiquitin-conjugating enzyme (UBC), and 60S ribosomal protein L40-1 (VvUbiquitin1), as references by using 'Aki Queen' grapes with and without ABA treatment. The main contribution of this study is that a gene expression analysis using GAPDH as a reference gene will help to elucidate the berry development process and the physiological effects of ABA on berry maturation of 'Aki Queen' grapes

Transverse instability due to the space charge during the electron-cooling bunching of ion beams

A beam-tracking simulation has been done for study of the electron- cooling bunching of ion beams around a few hundred MeV/u. In the simulation, the field due to the space charge of a beam in a round vacuum chamber is calculated from the charge distribution of macro- particles and the image particles due to the macro-particles. The simulation results show that the bunched beams meet a transverse instability more easily than coasting beams. (2 refs)

Early time dynamics of laser-ablated silicon using ultrafast grazing incidence X-ray scattering

Controlling the morphology of laser-derived nanomaterials is dependent on developing a better understanding of the particle nucleation dynamics in the ablation plume. Here, we utilize the femtosecond-length pulses from an x-ray free electron laser to perform time-resolved grazing incidence x-ray scattering measurements on a laser-produced silicon plasma plume. At 20 ps we observe a dramatic increase in the scattering amplitude at small scattering vectors, which we attribute to incipient formation of liquid silicon droplets. These results demonstrate the utility of XFELs as a tool for characterizing the formation dynamics of nanomaterials in laser-produced plasma plumes on ultrafast timescales