Cosmic Star Formation Activity at z=2.2 Probed by H-alpha Emission Line Galaxies

We present a pilot narrow-band survey of H-alpha emitters at z=2.2 in the Great Observatories Origins Deep Survey North (GOODS-N) field with MOIRCS instrument on the Subaru telescope. The survey reached a 3 sigma limiting magnitude of 23.6 (NB209) which corresponds to a 3 sigma limiting line flux of 2.5 x 10^-17 erg s^-1 cm^-2 over a 56 arcmnin^2 contiguous area (excluding a shallower area). From this survey, we have identified 11 H-alpha emitters and one AGN at z=2.2 on the basis of narrow-band excesses and photometric redshifts. We obtained spectra for seven new objects among them, including one AGN, and an emission line above 3 sigma is detected from all of them. We have estimated star formation rates (SFR) and stellar masses (M_star) for individual galaxies. The average SFR and M_star is 27.8M_solar yr^-1 and 4.0 x 10^10M_solar, respectivly. Their specific star formation rates are inversely correlated with their stellar masses. Fitting to a Schechter function yields the H-alpha luminosity function with log L = 42.82, log phi = -2.78 and alpha = -1.37. The average star formation rate density in the survey volume is estimated to be 0.31M_solar yr^-1Mpc^-3 according to the Kennicutt relation between H-alpha luminosity and star formation rate. We compare our H-alpha emitters at z=2.2 in GOODS-N with narrow-band line emitters in other field and clusters to see their time evolution and environmental dependence. We find that the star formation activity is reduced rapidly from z=2.5 to z=0.8 in the cluster environment, while it is only moderately changed in the field environment. This result suggests that the timescale of galaxy formation is different among different environments, and the star forming activities in high density regions eventually overtake those in lower density regions as a consequence of "galaxy formation bias" at high redshifts.Comment: Accepted for publication in PASJ Subaru Special Issue, 11 pages, 10 figure

An exocyst component, Sec5, is essential for ascospore formation in Bipolaris maydis

In this study, we identified Sec5 in Bipolaris maydis, a homologue of Sec5 in Saccharomyces cerevisiae and a possible exocyst component of the fungus. To examine how Sec5 affects the life cycle of B. maydis, we generated null mutant strains of the gene (Δsec5). The Δsec5 strains showed a strong reduction in hyphal growth and a slight reduction in pathogenicity. In sexual reproduction, they possessed the ability to develop pseudothecia. However, all ascospores were aborted in any of the asci obtained from crosses between Δsec5 and the wild-type. Our cytological study revealed that the abortion was caused by impairments of the post-meiotic stages in ascospore development, where ascospore delimitation and young spore elongation occur

Effects of Phytophthora sojae inoculation under flooded conditions on growth of soybean seedlings

Phytophthora root and stem rot due to Phytophthora sojae is a major constraint of soybean production. This study evaluated the combined effect of P. sojae inoculation and flooding on growth of soybean seedlings. The soybean cultivar ‘Enrei’ was grown in a greenhouse in pots containing vermiculite and containers of field soil. The plants were inoculated with two P. sojae isolates and subjected to flooding. The ratio of dead to live plants ranged from 0 to 0.32 across all treatments. Pathogen inoculation caused a significantly shorter maximum root length (MRL) in all the three experiments. MRL and shoot and root dry weight were affected by interaction between inoculation and flooding in one experiment with vermiculite media. Flooding affected the growth parameters only in the experiment with soil media. The results indicated that root of the soybean seedlings that survived from P. sojae infection grew less well than the non-inoculated plants

How Do Scale Insects Settle into the Nests of Plant-Ants on Macaranga Myrmecophytes? Dispersal by Wind and Selection by Plant-Ants

This report elucidates the process of settlement by Coccus scale insects into Crematogaster plant-ant nests formed inside the hollow stems of a myrmecophytic species, Macaranga bancana, in a tropical rain forest. We collected wafting scale insect nymphs from the canopy using sticky traps and characterized the DNA sequence of the trapped nymphs. In addition, we experimentally introduced first-instar nymphs of both symbiotic and nonsymbiotic scale insects to M. bancana seedlings with newly formed plant-ant colonies. Nymphs of symbiotic species were generally carried by ants into their nests within a few minutes of introduction. Most nymphs of nonsymbiotic species were thrown to the ground by ants. Our results suggest that in Crematogaster-Macaranga myrmecophytism, symbiotic coccids disperse by wind onto host plant seedlings at the nymphal stage, and plant-ants actively carry the nymphs landing on seedlings into their nests in discrimination from nonsymbiotic scale insects.ArticleSOCIOBIOLOGY. 59(2):435-446 (2012)journal articl

Synergistic defect in 60S ribosomal subunit assembly caused by a mutation of Rrs1p, a ribosomal protein L11-binding protein, and 3′-extension of 5S rRNA in Saccharomyces cerevisiae

Rrs1p, a ribosomal protein L11-binding protein, has an essential role in biogenesis of 60S ribosomal subunits. We obtained conditionally synthetic lethal allele with the rrs1-5 mutation and determined that the mutation is in REX1, which encodes an exonuclease. The highly conserved leucine at 305 was substituted with tryptophan in rex1-1. The rex1-1 allele resulted in 3′-extended 5S rRNA. Polysome analysis revealed that rex1-1 and rrs1-5 caused a synergistic defect in the assembly of 60S ribosomal subunits. In vivo and in vitro binding assays indicate that Rrs1p interacts with the ribosomal protein L5–5S rRNA complex. The rrs1-5 mutation weakens the interaction between Rrs1p with both L5 and L11. These data suggest that the assembly of L5–5S rRNA on 60S ribosomal subunits coordinates with assembly of L11 via Rrs1p

LIPUS effect on lateral tooth movement

Introduction: Because mechanical stimulation of the periodontal ligament (PDL) by low-intensity pulsed ultrasound (LIPUS) has been shown to increase the speed of bone remodeling, the aim of this study was to examine the effects of LIPUS stimulation on the rate of tooth movement and bone remodeling during lateral tooth movement. Methods: Twelve-week-old Wistar rats were divided into two groups. The LIPUS group received experimental tooth movement with LIPUS stimulation, and the tooth movement (TM) group had experimental tooth movement without LIPUS. For the LIPUS and TM groups, the upper right first molars were moved labially with fixed appliances. LIPUS exposure was placed in the region corresponding to the right maxillary first molar. Three days after tooth movement, tartrate-resistant acid phosphatase (TRAP) was examined. Fourteen days after tooth movement, the intermolar width, bone mineral content (BMC), and bone volume fraction (BV/TV) were examined by micro computed tomography (micro-CT), and newly formed bone was measured histomorphometrically. Results: The number of TRAP-positive cells at the compressed region was obviously greater in the LIPUS group. The intermolar width was significantly greater in the LIPUS group than in the TM group. The alveolar bone around the maxillary first molar showed no differences in BMC or BV/TV between the LIPUS and TM groups. The LIPUS group exhibited a significantly greater amount of newly formed alveolar bone than the TM group. Conclusions: The present study provides evidence of the beneficial effects of LIPUS on the lateral tooth movement

Paradoxical nature of narrative in analytical psychotherapy

This study explored the changes, obstacles for changes and the sharing of narratives in psychotherapeutic case studies. Study 1 developed an index for analyzing the process of narratives in psychotherapy, based on 101 cases. In Study 2, 203 cases were evaluated using the index generated from Study 1. As a result, three paradoxical natures of narrative became evident. Narrative in psychotherapy is thought to include (1) recognizing the beginning of a narrative, which can also signify the completion of the narrative, (2) negative movements that hinder the development of the narrative while at the same time move it forward and (3) an individual’s narrative that is uniquely one’s own, but easily influences and is influenced by the narratives of others

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