Salt Tolerance in Herbage and its Application to Greening the Desert

Canadian peat moss was used as water holding material and the efficacy of mixing the peat with the sand on water holding capacity of the sand, and the adaptability of alfalfa (AL), burmudagrass (BG), bahiagrass(BH), weeping lovegrass (WL) and Japanese lawngrass(JL) to dry and saline conditions were investigated. Without mixing peat, pF value of the sand did not change for 6 days after watering, but rose markedly up to 2.9 after 18 days. With mixing peat at the rate of 2% by the sand weight, the value did not change for 20 days, and rose gradually up to 2.5 on 30th. The yield of the herbages was the highest in the sand with peat at 2%, and WL showed the highest value followed by BG. Salt tolerance at germination and seedling tests was the strongest in BG and WL. Under the 100mM NaCl condition, the pattern of cation uptake in BG and WL showed lower Na uptake and K decline than in AL, BH and JL. Oxygen production in thylakoid membrane was the highest in BG and WL

Parallel Ion Flow Velocity Measurement Using Laser Induced Fluorescence Method in an Electron Cyclotron Resonance Plasma

Parallel ion flow velocity along a magnetic field has been measured using a laser induced fluorescence (LIF) method in an electron cyclotron resonance (ECR) argon plasma with a weakly-diverging magnetic field. To measure parallel flow velocity in a cylindrical plasma using the LIF method, the laser beam should be injected along device axis; however, the reflection of the incident beam causes interference between the LIF emission of the incident and reflected beams. Here we present a method of quasi-parallel laser injection at a small angle, which utilizes the reflected beam as well as the incident beam to obtain the parallel ion flow velocity. Using this method, we observed an increase in parallel ion flow velocity along the magnetic field. The acceleration mechanism is briefly discussed on the basis of the ion fluid model

Essential Factors for Incompatible DNA End Joining at Chromosomal DNA Double Strand Breaks In Vivo

Non-homologous end joining (NHEJ) is a major pathway for the repair of DNA double strand break (DSBs) with incompatible DNA ends, which are often generated by ionizing irradiation. In vitro reconstitution studies have indicated that NHEJ of incompatible DNA ends requires not only the core steps of synapsis and ligation, employing KU80/DNA-PKcs and LIG4, but also additional DNA end processing steps, such as DNA end resection by Artemis and gap-filling by POLλ and POLμ. It seems that DNA end processing steps are important for joining of incompatible DNA ends rather than compatible ends. Despite the fact that DNA end processing is important for incompatible DNA end joining in vitro, the role of DNA processing in NHEJ of incompatible DSBs in vivo has not yet been demonstrated. Here we investigated the in vivo roles of proteins implicated in each step of NHEJ using an assay in which NHEJ of incompatible DNA ends on chromosomal DNA can be assessed in living human cells. siRNA- or inhibitor-mediated impairment of factors in each NHEJ step resulted in a reduction in joining efficiency. Strikingly, stronger effects were observed when DNA end resection and ligation protein functions were impaired. Disruption of synapsis by KU80 and DNA-PKcs impairment, or the disruption of gap filling by POLλ and POLμ depletion, resulted in higher levels of microhomology-mediated joining. The present study indicates that DNA end resection and ligation factors are critical for the efficient joining of incompatible ends in vivo, further emphasizing the importance of synapsis and gap-filling factors in preventing illegitimate joining