984 research outputs found
Synchronized hatching as a possible strategy to avoid sibling cannibalism in stink bugs
In some animals, timing of egg hatching is adjusted in response to cues from clutch mates to synchronize hatching within a clutch and this typically facilitates mass migration of hatchlings from their natal clutch. A recent study in eight species of Pentatomidae revealed that four species show synchronized hatching due to responses to earlier-hatched siblings, by comparing temporal hatching patterns between intact clutches and eggs individually detached from clutches. However, hatchlings of Pentatomidae do not migrate from their natal clutch immediately. In the present study, using the same eight species, we explored the evolutionary reason for the synchronized hatching in Pentatomidae. In all of the species examined except one non-synchronized species, Eurydema rugosum, hatchlings showed egg feeding behavior with greatly different time of onset. The highly synchronized species, Halyomorpha halys and Nezara viridula, had the time of onset of egg feeding earlier than in the other species. In these two species, based on the hatching patterns of eggs individually detached from their clutches, we concluded that eggs can be cannibalized by their earlier-hatched siblings unless they hatch in response to siblings. On the other hand, this was not the case in the moderately synchronized species, Piezodorus hybneri and Plautia stali. In the other three non-synchronized species, Aelia fieberi, Dolycoris baccarum, and Palomena angulosa, eggs seemed not to incur a risk of cannibalism. In intact H. halys clutches, almost no eggs were cannibalized by siblings. In conclusion, synchronized hatching serves as a possible strategy to avoid sibling cannibalism in Pentatomidae, although it can also have some other functions
Validation of Short-Term Skin-Sensitizing Igg Antibodies to Egg in Atopic Dermatitis by Prausnitz-Küstner (P-K) and Oral P-K Tests
ABSTRACTWe tried to evaluate the role of IgG antibodies in the wheal and flare reaction of infantile atopic dermatitis by in vivo skin-sensitizing methods. Sera from 49 patients under 6 years of age were heated at 56°C for 30min to inactivate IgE antibodies, according to previous reports. Two-fold serial dilutions of the heated serum were injected intracutaneously in both forearms of a non-allergic recipient. One hour later, the whole egg antigen (1:1000) was injected in the serum transfer sites of an arm and the reaction was read at 15min (IgG Prausnitz-Küstner (P-K) test). Immediately afterwards, a raw hen's egg was swallowed by the recipient and the serum transfer sites of the other arm were observed for 2h (oral IgG P-K test). Three patients under 1 year of age showed an immediate wheal and flare reaction in the IgG P-K test, but none of the patients showed a positive reaction in the oral IgG P-K test. The patients with a positive IgG P-K test had an IgE radioallergosorbent test (RAST) score >4 to egg white and a positive IgE P-K titer of >28 to whole egg antigen. Two patients showed a positive reaction to the oral IgE P-K test to raw egg ingestion. Ovalbumin-specific IgG, lgG3 and lgG4 antibodies were assayed in 20 patients. IgG, and lgG3 antibodies were significantly increased in two patients with a positive IgG P-K test, while levels of the lgG4 antibody in positive patients were not significantly increased in comparison with levels in negative patients. In conclusion, these results suggest that the IgG antibody may play a role in the immediate type allergic reaction in infantile atopic dermatitis
How Cervical Reconstruction Surgery Affects Global Spinal Alignment.
BACKGROUND:There have been no reports describing how cervical reconstruction surgery affects global spinal alignment (GSA). OBJECTIVE:To elucidate the effects of cervical reconstruction for GSA through a retrospective multicenter study. METHODS:Seventy-eight patients who underwent cervical reconstruction surgery for cervical kyphosis were divided into a Head-balanced group (n = 42) and a Trunk-balanced group (n = 36) according to the values of the C7 plumb line (PL). We also divided the patients into a cervical sagittal balanced group (CSB group, n = 18) and a cervical sagittal imbalanced group (CSI group, n = 60) based on the C2 PL-C7 PL distance. Various sagittal Cobb angles and the sagittal vertical axes were measured before and after surgery. RESULTS:Cervical alignment was improved to achieve occiput-trunk concordance (the distance between the center of gravity [COG] PL, which is considered the virtual gravity line of the entire body, and C7 PL < 30 mm) despite the location of COG PL and C7PL. A subsequent significant change in thoracolumbar alignment was observed in Head-balanced and CSI groups. However, no such significant change was observed in Trunk-balanced and CSB groups. We observed 1 case of transient and 1 case of residual neurological worsening. CONCLUSION:The primary goal of cervical reconstruction surgery is to achieve occiput-trunk concordance. Once it is achieved, subsequent thoracolumbar alignment changes occur as needed to harmonize GSA. Cervical reconstruction can restore both cervical deformity and GSA. However, surgeons must consider the risks and benefits in such challenging cases
First-principles study on scanning tunneling microscopy images of hydrogen-terminated Si(110) surfaces
Scanning tunneling microscopy images of hydrogen-terminated Si(110) surfaces
are studied using first-principles calculations. Our results show that the
calculated filled-state images and local density of states are consistent with
recent experimental results, and the empty-state images appear significantly
different from the filled-state ones. To elucidate the origin of this
difference, we examined in detail the local density of states, which affects
the images, and found that the bonding and antibonding states of surface
silicon atoms largely affect the difference between the filled- and empty-state
images.Comment: 4 pages, and 4 figure
Genome-wide screening of the genes required for tolerance to vanillin, which is a potential inhibitor of bioethanol fermentation, in Saccharomyces cerevisiae
<p>Abstract</p> <p>Background</p> <p>Lignocellulosic materials are abundant and among the most important potential sources for bioethanol production. Although the pretreatment of lignocellulose is necessary for efficient saccharification and fermentation, numerous by-products, including furan derivatives, weak acids, and phenolic compounds, are generated in the pretreatment step. Many of these components inhibit the growth and fermentation of yeast. In particular, vanillin is one of the most effective inhibitors in lignocellulose hydrolysates because it inhibits fermentation at very low concentrations. To identify the genes required for tolerance to vanillin, we screened a set of diploid yeast deletion mutants, which are powerful tools for clarifying the function of particular genes.</p> <p>Results</p> <p>Seventy-six deletion mutants were identified as vanillin-sensitive mutants. The numerous deleted genes in the vanillin-sensitive mutants were classified under the functional categories for 'chromatin remodeling' and 'vesicle transport', suggesting that these functions are important for vanillin tolerance. The cross-sensitivity of the vanillin-sensitive mutants to furan derivatives, weak acids, and phenolic compounds was also examined. Genes for ergosterol biosynthesis were required for tolerance to all inhibitory compounds tested, suggesting that ergosterol is a key component of tolerance to various inhibitors.</p> <p>Conclusion</p> <p>Our analysis predicts that vanillin tolerance in <it>Saccharomyces cerevisiae </it>is affected by various complicated processes that take place on both the molecular and the cellular level. In addition, the ergosterol biosynthetic process is important for achieving a tolerance to various inhibitors. Our findings provide a biotechnological basis for the molecular engineering as well as for screening of more robust yeast strains that may potentially be useful in bioethanol fermentation.</p
A brief history of meteorological observations in French Indochina
In this study, we attempt to describe a brief history of meteorological observation and data in French Indochina based on materials found in libraries belonging to the national hydro-meteorological services of Japan, Vietnam, and France, and on the websites of the National Oceanic and Atmospheric Administration, USA and the National Library of France. In our search, we found very important publications relating to historical meteorological information in French Indochina for the period from the 1860’s to 1954. Before the establishment of the meteorological service of French Indochina, medical officers in the French Navy conducted meteorological observations. After the establishment of the meteorological service, its observation activities were strongly affected by French Indochina government policies. An image collection of historical meteorological information in French Indochina could potentially contribute to historical meteorological data recovery
Generation of optical Schr\"{o}dinger's cat states by generalized photon subtraction
We propose a high-rate generation method of optical Schr\"{o}dinger's cat
states. Thus far, photon subtraction from squeezed vacuum states has been a
standard method in cat-state generation, but its constraints on experimental
parameters limit the generation rate. In this paper, we consider the state
generation by photon number measurement in one mode of arbitrary two-mode
Gaussian states, which is a generalization of conventional photon subtraction,
and derive the conditions to generate high-fidelity and large-amplitude cat
states. Our method relaxes the constraints on experimental parameters, allowing
us to optimize them and attain a high generation rate. Supposing realistic
experimental conditions, the generation rate of cat states with large
amplitudes ( can exceed megacounts per second, about to
times better than typical rates of conventional photon subtraction. This
rate would be improved further by the progress of related technologies. Ability
to generate non-Gaussian states at a high rate is important in quantum
computing using optical continuous variables, where scalable computing
platforms have been demonstrated but preparation of non-Gaussian states of
light remains as a challenging task. Our proposal reduces the difficulty of the
state preparation and open a way for practical applications in quantum optics.Comment: 8 pages, 5 figure
Sclerite formation in the hydrothermal-vent “scaly-foot” gastropod — possible control of iron sulfide biomineralization by the animal
A gastropod from a deep-sea hydrothermal field at the Rodriguez triple junction, Indian Ocean, has scale-shaped structures, called sclerites, mineralized with iron sulfides on its foot. No other organisms are known to produce a skeleton consisting of iron sulfides. To investigate whether iron sulfide mineralization is mediated by the gastropod for the function of the sclerites, we performed a detailed physical and chemical characterization. Nanostructural characterization of the iron sulfide sclerites reveals that the iron sulfide minerals pyrite (FeS2) and greigite (Fe3S4) form with unique crystal habits inside and outside of the organic matrix, respectively. The magnetic properties of the sclerites, which are mostly consistent with those predicted from their nanostructual features, are not optimized for magnetoreception and instead support use of the magnetic minerals as structural elements. The mechanical performance of the sclerites is superior to that of other biominerals used in the vent environment for predation as well as protection from predation. These characteristics, as well as the co-occurrence of brachyuran crabs, support the inference that the mineralization of iron sulfides might be controlled by the gastropod to harden the sclerites for protection from predators. Sulfur and iron isotopic analyses indicate that sulfur and iron in the sclerites originate from hydrothermal fluids rather than from bacterial metabolites, and that iron supply is unlikely to be regulated by the gastropod for iron sulfide mineralization. We propose that the gastropod may control iron sulfide mineralization by modulating the internal concentrations of reduced sulfur compounds
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