89 research outputs found
Direct Nucleophilic Substitution of Alcohols Using an Immobilized Oxovanadium Catalyst
Direct nucleophilic substitution of alcohols with thiols or carbon nucleophiles was achieved using a mesoporous silica-supported oxovanadium catalyst (VMPS4). Benzyl and allyl alcohols were compatible in this reaction under mild conditions, affording the products in high yields. The VMPS4 catalyst showed excellent chemoselectivity toward alcohols in the presence of acid-labile functional groups, which is in contrast to that observed for the commonly used Lewis acid catalysts, which exhibit poor selectivity. The VMPS4 catalyst could be recycled by simple centrifugation, and the catalytic activity was maintained over seven cycles.This is the pre-peer reviewed version of the following article:Nishio T., Yoshioka S., Hasegawa K., et al. Direct Nucleophilic Substitution of Alcohols Using an Immobilized Oxovanadium Catalyst. European Journal of Organic Chemistry 2021, 4417 (2021), which has been published in final form at https://doi.org/10.1002/ejoc.202100569. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archivin
Identification of a second gene associated with variation in vertebral number in domestic pigs
<p>Abstract</p> <p>Background</p> <p>The number of vertebrae in pigs varies and is associated with body size. Wild boars have 19 vertebrae, but European commercial breeds for pork production have 20 to 23 vertebrae. We previously identified two quantitative trait loci (QTLs) for number of vertebrae on <it>Sus scrofa </it>chromosomes (SSC) 1 and 7, and reported that an orphan nuclear receptor, <it>NR6A1</it>, was located at the QTL on SSC1. At the <it>NR6A1 </it>locus, wild boars and Asian local breed pigs had the wild-type allele and European commercial-breed pigs had an allele associated with increased numbers of vertebrae (number-increase allele).</p> <p>Results</p> <p>Here, we performed a map-based study to define the other QTL, on SSC7, for which we detected genetic diversity in European commercial breeds. Haplotype analysis with microsatellite markers revealed a 41-kb conserved region within all the number-increase alleles in the present study. We also developed single nucleotide polymorphisms (SNPs) in the 450-kb region around the QTL and used them for a linkage disequilibrium analysis and an association study in 199 independent animals. Three haplotype blocks were detected, and SNPs in the 41-kb region presented the highest associations with the number of vertebrae. This region encodes an uncharacterized hypothetical protein that is not a member of any other known gene family. Orthologs appear to exist not only in mammals but also birds and fish. This gene, which we have named <it>vertnin </it>(<it>VRTN</it>) is a candidate for the gene associated with variation in vertebral number. In pigs, the number-increase allele was expressed more abundantly than the wild-type allele in embryos. Among candidate polymorphisms, there is an insertion of a SINE element (PRE1) into the intron of the Q allele as well as the SNPs in the promoter region.</p> <p>Conclusions</p> <p>Genetic diversity of <it>VRTN </it>is the suspected cause of the heterogeneity of the number of vertebrae in commercial-breed pigs, so the polymorphism information should be directly useful for assessing the genetic ability of individual animals. The number-increase allele of swine <it>VRTN </it>was suggested to add an additional thoracic segment to the animal. Functional analysis of <it>VRTN </it>may provide novel findings in the areas of developmental biology.</p
Active Initialization Experiment of Superconducting Qubit Using Quantum-circuit Refrigerator
The initialization of superconducting qubits is one of the essential
techniques for the realization of quantum computation. In previous research,
initialization above 99\% fidelity has been achieved at 280 ns. Here, we
demonstrate the rapid initialization of a superconducting qubit with a
quantum-circuit refrigerator (QCR). Photon-assisted tunneling of quasiparticles
in the QCR can temporally increase the relaxation time of photons inside the
resonator and helps release energy from the qubit to the environment.
Experiments using this protocol have shown that 99\% of initialization time is
reduced to 180 ns. This initialization time depends strongly on the relaxation
rate of the resonator, and faster initialization is possible by reducing the
resistance of the QCR, which limits the ON/OFF ratio, and by strengthening the
coupling between the QCR and the resonator
Microbial mat compositions and localization patterns explain the virulence of black band disease in corals
Black band disease (BBD) in corals is characterized by a distinctive, band-like microbial mat, which spreads across the tissues and often kills infected colonies. The microbial mat is dominated by cyanobacteria but also commonly contains sulfide-oxidizing bacteria (SOB), sulfate-reducing bacteria (SRB), and other microbes. The migration rate in BBD varies across different environmental conditions, including temperature, light, and pH. However, whether variations in the migration rates reflect differences in the microbial consortium within the BBD mat remains unknown. Here, we show that the micro-scale surface structure, bacterial composition, and spatial distribution differed across BBD lesions with different migration rates. The migration rate was positively correlated with the relative abundance of potential SOBs belonging to Arcobacteraceae localized in the middle layer within the mat and negatively correlated with the relative abundance of other potential SOBs belonging to Rhodobacteraceae. Our study highlights the microbial composition in BBD as an important determinant of virulence
Beta-glucan reflects liver injury after preservation and transplantation in dogs.
Graft failure and extrahepatic organ complications, which frequently develop after transplantation, may be related to inflammatory mediators stimulated by endotoxin (ET). The role of endotoxemia after liver transplantation is controversial and may depend upon differences in the ET assay method used in the various contradicting studies. While the standard Limulus amebocyte lysate (LAL) is reactive for ET and beta-glucan, a novel turbidimetric assay method enables separate determinations of ET and beta-glucan. Beagle dogs undergoing orthotopic liver transplantation were divided into two groups. In Group I (n = 6) the grafts were transplanted immediately and in Group II (n = 6) grafts were preserved for 48 h in University of Wisconsin (UW) solution. Animals received cyclosporine immunosuppression and were followed for 14 days. Daily measurements of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) were performed. Samples for ET and beta-glucan measurement were collected serially and processed using the turbidimetric assay method. While no graft failure was seen in Group I, three of six Group II animals died from graft failure within 1 day after transplantation. Preservation and reperfusion injury was much more severe in the Group II grafts than in Group I grafts. While endotoxemia could not be detected, postoperative beta-glucan levels (undetectable pretransplant) were seen in both groups. Beta-glucan levels were much higher in Group II grafts than in Group I grafts, and correlated with the severity of liver damage. In conclusion, this study shows that beta-glucan, instead of ET, appears during the early posttransplant period. We believe that posttransplant elevation of beta-glucan is related to liver damage, especially endothelial damage by preservation and reperfusion
<Abstract of published report>A 28 kDa-protein with disintegrin-like structure (jararhagin-C) purified from Bothrops jararaca venom inhibits collagen- and ADP-induced platelet aggregation.
Median raphe serotonergic neurons projecting to the interpeduncular nucleus control preference and aversion
不快感を誘発するセロトニン神経を発見 --セロトニン神経の多様性が明らかに--. 京都大学プレスリリース. 2022-12-23.Appropriate processing of reward and aversive information is essential for survival. Although a critical role of serotonergic neurons in the dorsal raphe nucleus (DRN) in reward processing has been shown, the lack of rewarding effects with selective serotonin reuptake inhibitors (SSRIs) implies the presence of a discrete serotonergic system playing an opposite role to the DRN in the processing of reward and aversive stimuli. Here, we demonstrated that serotonergic neurons in the median raphe nucleus (MRN) of mice process reward and aversive information in opposite directions to DRN serotonergic neurons. We further identified MRN serotonergic neurons, including those projecting to the interpeduncular nucleus (5-HTMRN→IPN), as a key mediator of reward and aversive stimuli. Moreover, 5-HT receptors, including 5-HT2A receptors in the interpeduncular nucleus, are involved in the aversive properties of MRN serotonergic neural activity. Our findings revealed an essential function of MRN serotonergic neurons, including 5-HTMRN→IPN, in the processing of reward and aversive stimuli
<Abstract of published report>Purification and characterization of bothrombin, a fibrinogen-clotting serine protease from the venom of Bothrops jararaca.
Differences in Trocar Positioning within the Vertebral Body Using Two Different Positioning Methods: Effect on Trainee Performance
Purpose. To evaluate the educational effect of the Japanese Society of Interventional Radiology 7th Academic Summer Seminar from a technical perspective. Materials and Methods. Nineteen trainees participated in the seminar. The seminar consisted of vertebroplasty trainings using swine with the single-plane landmark method and with the ISOcenter Puncture (ISOP) method. All trainees were advised by an instructor as they operated the instruments and punctured the vertebra. For each trainee, the accuracy in the final position of the needle tip of the initial puncture in each swine training was evaluated. Results. Error in the final position of the needle tip of ≥5 mm from the target puncture site occurred in the lateral direction in 42% (8/19) of trainees with the landmark method and 5% (1/19) with the ISOP method. No error ≥5 mm occurred in the vertical or anteroposterior directions. In terms of puncture accuracy, error in the lateral direction was significantly lower with the ISOP method than with the landmark method (2.2 ± 1.5 mm versus 5.6 ± 3.2 mm). Conclusion. This seminar was effective training for trocar placement for beginners. The puncture was more accurate with the ISOP method than with the landmark method
Heliocentric Distance Dependence of Zodiacal Light Observed by Hayabusa2#
Zodiacal light (ZL) is sunlight scattered by interplanetary dust particles
(IDPs) at optical wavelengths. The spatial distribution of IDPs in the Solar
System may hold an important key to understanding the evolution of the Solar
System and material transportation within it. The number density of IDPs can be
expressed as , and the exponent was
obtained by previous observations from interplanetary space by Helios 1/2 and
Pioneer 10/11 in the 1970s and 1980s. However, no direct measurements of
based on ZL observations from interplanetary space outside Earth's
orbit have been performed since then. Here, we introduce initial results for
the radial profile of the ZL at optical wavelengths observed over the range
0.76-1.06 au by ONC-T aboard the Hayabusa2# mission in 2021-2022. The ZL
brightness we obtained is well reproduced by a model brightness, although there
is a small excess of the observed ZL brightness over the model brightness at
around 0.9 au. The radial power-law index we obtained is , which is consistent with previous results based on ZL observations. The
dominant source of uncertainty arises from the uncertainty in estimating the
diffuse Galactic light (DGL).Comment: 22 pages, 19 figures, 4 tables, accepted for publication by Earth,
Planets and Spac
- …