Comparison of thread-cutting behaviour in three specialist predatory mites to cope with complex webs of Tetranychus spider mites

Anti-predator defenses provided by complex webs of Tetranychus mites can severely impede the performance of generalist predatory mites, whereas this may not be true for specialist predatory mites. Although some specialist predatory mites have developed morphological protection to reduce the adverse effects of complex webs, little is known about their behavioral abilities to cope with the webs. In this study, we compared thread-cutting behavior of three specialist predatory mites, Phytoseiulus persimilis, Neoseiulus womersleyi and N. californicus, exhibited inside the complex web of T. urticae. No major difference was observed among them in the basic pattern of this behavior, using chelicerae and palps, and in the number of silken threads severed while moving inside the web. These results and observations suggest that each predator species cut many sticky silken threads to move inside the complex web without suffering from serious obstructio

A combined treatment of ionomycin with ethanol improves blastocyst development of bovine oocytes harvested from stored ovaries and microinjected with spermatozoa

Regardless of the presence of sperm-borne oocyte-activating factors, activation of bovine oocytes with exogenous activation stimuli is required for further development after intracytoplasmic sperm injection (ICSI). The current study was designed to develop a new activation regimen for improving the blastocyst yield after ICSI of bovine oocytes harvested from ovaries stored at 10 to 12 degrees C for 24 h. After ICSI, oocytes were treated with 5 mu M ionomycin for 5 min, 7% ethanol for 5 or 10 min, ionomycin followed by ethanol (5 or 10 min), ionomycin followed by 10 mu g/mL cycloheximide for 5 h, or ionomycin followed by 1.9 mM 6-dimethylaminopurine for 3 h. Across the activation regimens, the cleavage rates of ICSI oocytes (45% to 77%) were higher than those of parthenogenetically activated oocytes (11% to 21%; P 0.05). Higher blastocyst yields were due to increasing the proportion of ICSI oocytes that passed through the early postfertilization events until cleavage. None of the regimens have any adverse effect on the quality of the blastocysts regarding the total cell number or the proportion of the inner cell mass cells. Thus, a new activation regimen using two triggers for single calcium increase effectively improved blastocyst yield after bovine ICSI using oocytes harvested from stored ovaries.ArticleTHERIOGENOLOGY. 72(4):453-460 (2009)journal articl

Generalized constraints on quantum amplification

We derive quantum constraints on the minimal amount of noise added in linear amplification involving input or output signals whose component operators do not necessarily have c-number commutators, as is the case for fermion currents. This is a generalization of constraints derived for the amplification of bosonic fields whose components posses c-number commutators.Comment: 4 pages, 1 figure, submitted to Physical Review Letter

Universal optical amplification without nonlinearity

We propose and experimentally realize a new scheme for universal phase-insensitive optical amplification. The presented scheme relies only on linear optics and homodyne detection, thus circumventing the need for nonlinear interaction between a pump field and the signal field. The amplifier demonstrates near optimal quantum noise limited performance for a wide range of amplification factors.Comment: 5 pages, 4 figure

Sulfur-Mediated Palladium Catalyst Immobilized on a GaAs Surface

We present a hard x-ray photoelectron spectroscopy study on the preparation process of palladium catalyst immobilized on an S-terminated GaAs(100) surface. It is revealed that Pd(II) species are reduced on the GaAssurface and yield Pd nanoparticles during the process of Pd immobilization and the subsequent heat treatment. A comparison with the results on GaAs without S-termination suggests that the reduction of Pd is promoted by hydroxy groups during the Pd immobilization and by S during the heat treatment

Polyphenol Concentration of Native Plant Species, and Its Effect on Blood Antioxidant Capacity in Grazing Cattle in a Species-Rich Vegetation in Japan

It is known that polyphenols in plants have a high antioxidant capacity. However, there is scarce information on its concentration in native plants and the effect of antioxidant capacity to grazing animals. In this study, polyphenol concentration of available plants was investigated in a species-rich grazing area in north-eastern district of Japan. In addition, polyphenol concentration in blood serum of grazing cattle was also measured. Eight beef cows grazed in a grazing area (hill pasture 3.1 ha; forest 16.9 ha) from late spring to mid-autumn (142 days), and four cows among the eight grazed at an orchardgrass pasture in mid-summer (10 days). During the grazing period, foraging behaviour was directly observed, and plant species proportion in ingesta and residence time in the hill pasture and the forest were measured. Based on these results, the top 10–13 species were hand-clipped by mimicking foraging manner of cows, and total polyphenol and catechin concentration were measured. Blood samples of cows were also collected during the grazing period, and potential antioxidant [PAO] and serum total antioxidant status [STAS] were analysed. The cows ingested 17–32 plant species in the hill pasture, and 53–73 species in the forest. In contrast, the cows ingested mainly orchardgrass in the sown pasture in mid-summer. Total polyphenol and catechin concentration were higher in tree leaves (112.8–209.3 g/kg DM, 0.081–6.250 g/kg DM) than monocots (11.9–34.0 g/kg DM, 0–0.159g/kg DM). However, those concentration in ingesta of the cows were low throughout the seasons (35.0–56.9 g/kg DM, 0.108–0.467 g/kg DM), as in the sown pasture (26.2 g/kg DM, 0.158 g/kg DM), due to high proportion of monocots in ingesta at the hill pasture (67–75%). PAO (373.4–455.8 μ mol/L) and STAS (769.8–910.0 μ mol/L) of the cows were almost constant throughout the seasons

Stimulatory effect of Rho-associated coiled-coil kinase (ROCK) inhibitor on revivability of in vitro-produced bovine blastocysts after vitrification

Inhibition of Rho-associated kinase (ROCK) activity promoted recovery and growth of frozen-thawed human embryonic stem cells. The primary objective was to determine if a ROCK inhibitor (Y-27632) in post-thaw culture medium unproved revivability of vitrified IVP bovine blastocysts. Expanding or expanded blastocysts (7 d after IVF) were vitrified (minimum volume cooling procedure, using a Cryotop) in 15% ethylene glycol. 15% DMSO and 0 5 M sucrose When post-warm blastocysts were cultured in inSOF medium, survival rate (re-expansion of blastocoel at 24 h of culture) was improved (P < 0 05) by the addition of 10 mu M Y-27632 (94 9 +/- 2 4%, mean +/- SEM) compared to a control (78 0 +/- 6 0%) Conversely. after 48 h of culture, there were no significant differences in hatching late (62.8 +/- 11 1 vs 59 6 +/- 9.4%) and mean total cell number (135 2 +/- 13 1 vs. 146 7 +/- 13 3) In non-vitrified IVP bovine blastocysts, the hatching rate on Day 9 was improved by Y-27632 (91 7 +/- 3 8 vs 54 7 +/- 8 9%. P < 0 05). with no difference in mean total cell number of blastocysts (230 0 +/- 23 0 vs 191 2 +/- 22 2, P = 0 23). In an additional experiment, Y-27632 was added to culture medium on either Day 0, Day 2. or Day 4 (and remained present until Day 8). resulting in no improvement in blastocyst yield compared to a control group (7.5 +/- 2 1, 31 4 +/- 2 3, 36 2 +/- 3.2. and 28.6 +/- 6.9%. respectively) In conclusion, adding a ROCK inhibitor to post-thaw culture medium improved revivability of IVP bovine blastocysts after vitrification and warmingArticleTHERIOGENOLOGY. 73(8):1139-1145 (2010)journal articl