AIM: To investigate an association between N -acetyltransferase 2 (NAT2 )-haplotypes/diplotypes and adverse effects in Japanese pulmonary tuberculosis patients. METHODS: We studied 100 patients with pulmonary TB treat...AIM: To investigate an association between N -acetyltransferase 2 (NAT2 )-haplotypes/diplotypes and adverse effects in Japanese pulmonary tuberculosis patients. METHODS: We studied 100 patients with pulmonary TB treated with anti-TB drugs including INH. The frequencies and distributions of single nucleotide polymorphisms, haplotypes, and diplotypes of NAT2 were determined by the PCR-restriction fragment length polymorphism method, and the results were compared between TB patients with and without adverse effect, using multivariate logistic regression analysis.RESULTS: Statistical analysis revealed that the frequency of a variant haplotype, NAT2*6A , was signifi cantly increased in TB patients with hepatotoxicity, compared with those without hepatotoxicity [P = 0.001, odds ratio (OR) = 3.535]. By contrast, the frequency of a wild-type (major) haplotype, "NAT2*4", was signif icantly lower in TB patients with hepatotoxicity than those without hepatotoxicity (P < 0.001, OR = 0.265). There was no association between NAT2-haplotypes and skin rash or eosinophilia. CONCLUSION: The present study shows that NAT2 is one of the determinants of anti-TB drug-induced hepatotoxicity. Moreover, the haplotypes, NAT2*4 and NAT2*6A, are useful new biomarkers for predicting anti- TB drug-induced hepatotoxicity.展开更多
The use of machine learning in computational molecular design has great potential to accelerate the discovery of innovative materials.However,its practical benefits still remain unproven in real-world applications,par...The use of machine learning in computational molecular design has great potential to accelerate the discovery of innovative materials.However,its practical benefits still remain unproven in real-world applications,particularly in polymer science.We demonstrate the successful discovery of new polymers with high thermal conductivity,inspired by machine-learning-assisted polymer chemistry.This discovery was made by the interplay between machine intelligence trained on a substantially limited amount of polymeric properties data,expertise from laboratory synthesis and advanced technologies for thermophysical property measurements.Using a molecular design algorithm trained to recognize quantitative structure—property relationships with respect to thermal conductivity and other targeted polymeric properties,we identified thousands of promising hypothetical polymers.From these candidates,three were selected for monomer synthesis and polymerization because of their synthetic accessibility and their potential for ease of processing in further applications.The synthesized polymers reached thermal conductivities of 0.18–0.41 W/mK,which are comparable to those of state-of-the-art polymers in non-composite thermo-plastics.展开更多
In plants, the phloem is the component of the vascular system that delivers nutrients and transmits signals from mature leaves to developing sink tissues. Recent studies have identified proteins, mRNA, and small RNA w...In plants, the phloem is the component of the vascular system that delivers nutrients and transmits signals from mature leaves to developing sink tissues. Recent studies have identified proteins, mRNA, and small RNA within the phloem sap of several plant species. It is now of considerable interest to elucidate the biological functions of these potential long-distance signal agents, to further our understanding of how plants coordinate their developmental programs at the whole-plant level. In this study, we developed a strategy for the functional analysis of phloem-mobile mRNA by focusing on IAA transcripts, whose mobility has previously been reported in melon (Cucumis melo cv. Hale's Best Jumbo). Indoleacetic acid (IAA) proteins are key transcriptional regulators of auxin signaling, and are involved in a broad range of developmental processes including root development. We used a combination of vasculature-enriched sampling and hetero-grafting techniques to identify IAA18 and IAA28 as phloemmobile transcripts in the model plant Arabidopsis thaliana. Micro-grafting experiments were used to confirm that these IAA transcripts, which are generated in vascular tissues of mature leaves, are then transported into the root system where they negatively regulate lateral root formation. Based on these findings, we present a model in which auxin distribution, in combination with phloem-mobile Aux/IAA transcripts, can determine the sites of auxin action.展开更多
In orchards, measuring crown characteristics is essential for monitoring the dynamics of tree growth and optimizing farm management. However, it lacks a rapid and reliable method of extracting the features of trees wi...In orchards, measuring crown characteristics is essential for monitoring the dynamics of tree growth and optimizing farm management. However, it lacks a rapid and reliable method of extracting the features of trees with an irregular crown shape such as trained peach trees. Here, we propose an efficient method of segmenting the individual trees and measuring the crown width and crown projection area (CPA) of peach trees with time-series information, based on gathered images. The images of peach trees were collected by unmanned aerial vehicles in an orchard in Okayama, Japan, and then the digital surface model was generated by using a Structure from Motion (SfM) and Multi-View Stereo (MVS) based software. After individual trees were identified through the use of an adaptive threshold and marker-controlled watershed segmentation in the digital surface model, the crown widths and CPA were calculated, and the accuracy was evaluated against manual delineation and field measurement, respectively. Taking manual delineation of 12 trees as reference, the root-mean-square errors of the proposed method were 0.08 m (R^(2) = 0.99) and 0.15 m (R^(2) = 0.93) for the two orthogonal crown widths, and 3.87 m2 for CPA (R^(2) = 0.89), while those taking field measurement of 44 trees as reference were 0.47 m (R^(2) = 0.91), 0.51 m (R^(2) = 0.74), and 4.96 m2 (R^(2) = 0.88). The change of growth rate of CPA showed that the peach trees grew faster from May to July than from July to September, with a wide variation in relative growth rates among trees. Not only can this method save labour by replacing field measurement, but also it can allow farmers to monitor the growth of orchard trees dynamically.展开更多
Dual-comb spectroscopy(DCS)is an emerging spectroscopic tool with the potential to simultaneously achieve a broad spectral coverage and ultrahigh spectral resolution with rapid data acquisition.However,the need for tw...Dual-comb spectroscopy(DCS)is an emerging spectroscopic tool with the potential to simultaneously achieve a broad spectral coverage and ultrahigh spectral resolution with rapid data acquisition.However,the need for two independently stabilized ultrafast lasers significantly hampers the potential application of DCS.We demonstrate mode-resolved DCS in the THz region based on a free-running singlecavity dual-comb fiber laser with the adaptive sampling method.While the use of a free-running single-cavity dual-comb fiber laser eliminates the need for two mode-locked lasers and their frequency control,the adaptive sampling method strongly prevents the degradation of spectroscopic performance caused by the residual timing jitter in the free-running dual-comb laser.Doppler-limit-approaching absorption features with linewidths down to 25 MHz are investigated for low-pressure acetonitrile/air mixed gas by comb-mode-resolved THz spectroscopy.The successful demonstration clearly indicates its great potential for the realization of lowcomplexity,Doppler-limited THz spectroscopy instrumentation.展开更多
Strigolactones (SLs) are a novel class of plant hormones and rhizosphere communication signals, although the molecular mechanisms underlying their activities have not yet been fully determined. Nor is their applicat...Strigolactones (SLs) are a novel class of plant hormones and rhizosphere communication signals, although the molecular mechanisms underlying their activities have not yet been fully determined. Nor is their application in agriculture well developed. The importance of plant hormone agonists has been demonstrated in both basic and applied research, and chemicals that mimic strigolactone functions should greatly facilitate strigolactone research. Here, we report our discovery of a new phenoxyfuranone compound, 4-Br debranone (4BD), that shows similar activity to that of the major strigolactone (SL) analog GR24 in many aspects of a biological assay on plants. 4BD strongly inhibited tiller bud outgrowth in the SL-deficient rice mutant d10 at the same concentration as GR24, with no adverse effects, even dur- ing prolonged cultivation. This result was also observed in the Arabidopsis thaliana SL-deficient mutants max1, max3, and max4. However, the application of 4BD to the Arabidopsis SL-insensitive mutant max2 induced no morphological changes in it. The expression of SL biosynthetic genes was also reduced by 4BD treatment, probably via negative feed- back regulation. However, in a seed germination assay on Striga hermonthica, a root parasitic plant, 4BD showed far less activity than GR24. These results suggest that 4BD is the first plant-specific strigolactone mimic.展开更多
Machine learning is becoming a valuable tool for scientific discovery.Particularly attractive is the application of machine learning methods to the field of materials development,which enables innovations by discoveri...Machine learning is becoming a valuable tool for scientific discovery.Particularly attractive is the application of machine learning methods to the field of materials development,which enables innovations by discovering new and better functional materials.To apply machine learning to actual materials development,close collaboration between scientists and machine learning tools is necessary.However,such collaboration has been so far impeded by the black box nature of many machine learning algorithms.It is often difficult for scientists to interpret the data-driven models from the viewpoint of material science and physics.Here,we demonstrate the development of spin-driven thermoelectric materials with anomalous Nernst effect by using an interpretable machine learning method called factorized asymptotic Bayesian inference hierarchical mixture of experts(FAB/HMEs).Based on prior knowledge of material science and physics,we were able to extract from the interpretable machine learning some surprising correlations and new knowledge about spin-driven thermoelectric materials.Guided by this,we carried out an actual material synthesis that led to the identification of a novel spin-driven thermoelectric material.This material shows the largest thermopower to date.展开更多
Magnetically recyclable Au/Co/Fe core-shell nanoparticles (NPs) have been successfully synthesized via a one-step in situ procedure. Transmission electron microscope (TEM), energy dispersive X-ray spectroscopic (...Magnetically recyclable Au/Co/Fe core-shell nanoparticles (NPs) have been successfully synthesized via a one-step in situ procedure. Transmission electron microscope (TEM), energy dispersive X-ray spectroscopic (EDS), and electron energy-loss spectroscopic (EELS) measurements revealed that the trimetallic Au/Co/Fe NPs have a triple-layered core-shell structure composed of a Au core, a Co-rich inter-layer, and a Fe-rich shell. The Au/Co/Fe core-shell NPs exhibit much higher catalytic activities for hydrolytic dehydrogenation of ammonia borane (NHBBH3, AB) than the monometallic (Au, Co, Fe) or bimetallic (AuCo, AuFe, CoFe) counterparts.展开更多
Entanglement has been recognized as being crucial when implementing various quantum information tasks.Nevertheless, quantifying entanglement for an unknown quantum state requires nonphysical operations or post-process...Entanglement has been recognized as being crucial when implementing various quantum information tasks.Nevertheless, quantifying entanglement for an unknown quantum state requires nonphysical operations or post-processing measurement data. For example, evaluation methods via quantum state tomography require vast amounts of measurement data and likely estimation.展开更多
γ-Butyrolactone structures are commonly found in various natural products and serve as crucial building blocks in organic synthesis.Consequently,the development of methods for synthesizingγ-butyrolactones has garner...γ-Butyrolactone structures are commonly found in various natural products and serve as crucial building blocks in organic synthesis.Consequently,the development of methods for synthesizingγ-butyrolactones has garnered significant interest within the organic synthesis community.In this study,we present a direct and highly efficient approach for the synthesis ofγ-butyrolactones from allylic alcohols.Notably,this study represents the first instance ofγ-butyrolactone synthesis initiated by radical hydrocarboxylation using CO_(2)^(•–),generated from metal formates,followed by cyclization.This two-step process is achieved through the synergistic interaction of photoredox and hydrogen atom transfer(HAT)catalysis,resulting in the production ofγ-butyrolactones with exceptional efficiency.Additionally,when employingα,α-diaryl allylic alcohol derivatives as substrates,the reaction involves 1,2-aryl migration,which occurs concomitantly with CO_(2)^(•–)addition,leading to the formation of 4,5-substituted lactones in a good yield.The artificial force induced reaction(AFIR)method identified the preferred 1,2-aryl migration pathway along with potential byproduct pathways,in which the targeted 1,2-migration was found to be the most plausible pathway.展开更多
Heat treatment of metal-organic frameworks(MOFs)has provided a wide variety of functional carbons coordinated with metal compounds.In this study,two kinds of zinc-based MOF(ZMOF),C_(16)H_(10)O_(4)Zn(ZMOF1)and C_(8)H_(...Heat treatment of metal-organic frameworks(MOFs)has provided a wide variety of functional carbons coordinated with metal compounds.In this study,two kinds of zinc-based MOF(ZMOF),C_(16)H_(10)O_(4)Zn(ZMOF1)and C_(8)H_(4)O_(4)Zn(ZMOF2),were prepared.ZMOF1 and ZMOF2 were carbonized at 1000℃,forming CZMOF1 and CZMOF2,respectively.The specific surface area(S_(BET))of CZMOF2 was~2700 m^(2)g^(−1),much higher than that of CZMOF1(~1300 m^(2)g^(−1)).A supercapacitor electrode based on CZMOF2 achieved specific capacitances of 360,278,and 221 F g^(−1)at 50,250,and 1000 mA g^(−1)in an aqueous electrolyte(H2SO_(4)),respectively,the highest values reported to date for ZMOF-derived electrodes under identical conditions.The practical applicability of the CZMOF-based supercapacitor was verified in non-aqueous electrolytes.The initial capacitance retention was 78%after 100000 charge/discharge cycles at 10 A g^(−1).Crucially,the high capacitance of CZMOF2 arises from pore generation during carbonization.Below 1000℃,pore generation is dominated by the Zn/C ratio of ZMOFs,as carbon atoms reduce the zinc oxides formed during carbonization.Above 1000℃,a high O/C ratio becomes essential for pore generation because the oxygen functional groups are pyrolyzed.These findings will provide insightful information for other metal-based MOFderived multifunctional carbons.展开更多
miRNAs are important regulators of gene expression and play key roles in the development of cancer, including osteosarcoma. During the development of osteosarcoma, the expression of miR-22 is significantly downregulat...miRNAs are important regulators of gene expression and play key roles in the development of cancer, including osteosarcoma. During the development of osteosarcoma, the expression of miR-22 is significantly downregulated, making miR-22 as a promising therapeutic target against osteosarcoma. To design and fabricate efficient delivery carriers of miR-22 into osteosarcoma cells, a hydroxyl-rich reduction-responsive cationic polymeric nanoparticle, TGIC-CA (TC), was developed in this work, which also enhanced the therapeutic effects of Volasertib on osteosarcoma. TC was prepared by the ring-opening reaction between amino and epoxy groups by one-pot method, which had the good complexing ability with nucleic acids, reduction-responsive degradability and gene transfection performance. TC/miR-22 combined with volasertib could inhibit proliferation, migration and promote apoptosis of osteosarcoma cells in vitro. The anti-tumor mechanisms were revealed as TC/ miR-22 and volasertib could inhibit the PI3K/Akt signaling pathway synergistically. Furthermore, this strategy showed outstanding tumor suppression performance in animal models of orthotopic osteosarcoma, especially in patient-derived chemo-resistant and chemo-intolerant patient-derived xenograft (PDX) models, which reduced the risk of tumor lung metastasis and overcame drug resistance. Therefore, it has great potential for efficient treatment of metastasis and drug resistance of osteosarcoma by the strategy of localized, sustained delivery of miR-22 using the cationic nanocarriers combined with non-traditional chemotherapy drugs.展开更多
The development of reliable catalysts with both excellent activity and recyclability for carbon dioxide(CO_(2))hydrogenation is challenging.Herein,a ternary hybrid heterogeneous catalyst,involving mononuclear Ru compl...The development of reliable catalysts with both excellent activity and recyclability for carbon dioxide(CO_(2))hydrogenation is challenging.Herein,a ternary hybrid heterogeneous catalyst,involving mononuclear Ru complex,N,P-containing porous organic polymers(POPs),and mesoporous hollow carbon spheres(Ru^(3+)-POPs@MHCS)is reported for CO_(2)hydrogenation to formate.Based on comprehensive structural analyses,we demonstrated that Ru^(3+)-POPs were successfully immobilized within MHCS.The optimized Ru^(3+)-0.5POPs@MHCS catalyst,which was obtained with about 5 wt.%Ru^(3+)and 0.5 mmol POPs polymers confined into 0.3 g MHCS,exhibited high catalytic activity for CO_(2)hydrogenation to formate(turnover number(TON)>1,200 for 24 h under mild reaction conditions(4.0 MPa,120℃))and improved durability,compared to Ru^(3+)catalysts without POPs polymers(Ru^(3+)-MHCS)and unencapsulated MHCS(Ru^(3+)-0.5POPs)catalysts.The improved catalytic performance is attributed to the high surface area and large pore volume of MHCS which favors dispersion and stabilization of Ru^(3+)-POPs.Furthermore,the MHCS and POPs showed high CO_(2)adsorption ability.Ru^(3+)-POPs encapsulated into MHCS reduces the activation energy barrier for CO_(2)hydrogenation to formate.展开更多
Dislocation-mediated plasticity in inorganic semiconductors and oxides has attracted increasing research interest because of the promising mechanical and functional properties tuned by dislocations.In this study,we in...Dislocation-mediated plasticity in inorganic semiconductors and oxides has attracted increasing research interest because of the promising mechanical and functional properties tuned by dislocations.In this study,we investigated the effects of light illumination on the dislocation-mediated plasticity in hexagonal wurtzite ZnO,a representative third-generation semiconductor material.A(0001)45o off sample was specially designed to preferentially activate the basal slip on(0001)plane.Three types of nanoindentation tests were performed under four different light conditions(550 nm,334 nm,405 nm,and darkness),including low-load(60μN)pop-in tests,high-load(500μN)nanoindentation tests,and nanoindentation creep tests.The maximum shear stresses at pop-in were found to approximate the theoretical shear strength regardless of the light conditions.The activation volume at pop-ins was calculated to be larger in light than in darkness.Cross-sectional transmission electron microscope images taken from beneath the indentation imprints showed that all indentation-induced dislocations were located beneath the indentation imprint in a thin-plate shape along one basal slip plane.These indentation-induced dislocations could spread much deeper in darkness than in light,revealing the suppressive effect of light on dislocation behavior.An analytical model was adopted to estimate the elastoplastic stress field beneath the indenter.It was found that dislocation glide ceased at a higher stress level in light,indicating the increase in the Peierls barrier under light illumination.Furthermore,nanoindentation creep tests showed the suppression of both indentation depth and creep rate by light.Nanoindentation creep also yielded a larger activation volume in light than in darkness.展开更多
Pollen tube guidance is controlled by multiple complex interactions with the female tissues. Here, we show that pollen tubes of Torenia fournieri are regulated by a stylar tissue in a length-dependent manner to receiv...Pollen tube guidance is controlled by multiple complex interactions with the female tissues. Here, we show that pollen tubes of Torenia fournieri are regulated by a stylar tissue in a length-dependent manner to receive and respond to attractant LURE peptides secreted from synergid cells. We developed an immunostaining method to visualize LURE peptides bound at the plasma membrane of the tip region of the pollen tube. Using this method, we found that LURE peptides bound specifically to pollen tubes growing through a cut style. The peptides also bound to pollen tubes growing through a shorter style, which were not competent to respond to these peptides. These observations suggested a possibility that acquisition of the LURE peptide reception ability and acquisition of full competency are separable pro- cesses. RNA-Seq suggested that the transcription profile of pollen tubes was affected by both the length of the style and the cultivation period, consistently with physiological changes in binding activity and LURE response ability. The data- base generated from de novo RNA-Seq of Torenia pollen tubes was shown to be useful to identify pollen tube proteins by mass spectrometry. Our studies provide insight and an effective platform for protein identification to understand pollen tube guidance.展开更多
A large number of 3D models are created on computers and available for networks. Some content-based retrieval technologies are indispensable to find out particular data from such anonymous datasets. Though several sha...A large number of 3D models are created on computers and available for networks. Some content-based retrieval technologies are indispensable to find out particular data from such anonymous datasets. Though several shape retrieval technologies have been developed, little attention has been given to the points on human's sense and impression (as known as Kansei) in the conventional techniques, In this paper, the authors propose a novel method of shape retrieval based on shape impression of human's Kansei. The key to the method is the Gaussian curvature distribution from 3D models as features for shape retrieval. Then it classifies the 3D models by extracted feature and measures similarity among models in storage.展开更多
The fabrication of heterostructures of two-dimensional semiconductors with specific bandgaps is an important approach to realizing the full potential of these materials in electronic and optoelectronic devices. Severa...The fabrication of heterostructures of two-dimensional semiconductors with specific bandgaps is an important approach to realizing the full potential of these materials in electronic and optoelectronic devices. Several groups have recently reported the direct growth of lateral and vertical heterostructures based on monolayers of typical semiconducting transition metal dichalcogenides (TMDCs) such as WSe2, MoSe2, WS2, and MoS2. Here, we demonstrate the single-step direct growth of lateral and vertical heterostructures based on bandgap-tunable Mo1-xWxS2 alloy monolayers by the sulfurization of patterned thin films of WO3 and MoO3. These patterned films are capable of generating a wide variety of concentration gradients by the diffusion of transition metals during the crystal growth phase. Under high temperatures, this leads to the formation of monolayer crystals of Mo1-xWxS2 alloys with various compositions and bandgaps, depending on the positions of the crystals on the substrates. Heterostructures of these alloys are obtained through stepwise changes in the ratio of W/Mo within a single domain during low-temperature growth. The stabilization of the monolayer Mo1-xWxS2 alloys, which often degrade even under gentle conditions, was accomplished by coating the alloys with other monolayers. The present findings demonstrate an efficient means of both studying and optimizing the optical and electrical properties of TMDC-based heterostructures to allow use of the materials in future device applications.展开更多
Relaxation of electronic excited-state and vibrational dynamics in the electronic excited state in Ru II(TPP)(CO) [TPP=tetraphenylporphyrin] dissolved in N2 bubbled benzene,O2 bubbled benzene,N2 bubbled chloroform and...Relaxation of electronic excited-state and vibrational dynamics in the electronic excited state in Ru II(TPP)(CO) [TPP=tetraphenylporphyrin] dissolved in N2 bubbled benzene,O2 bubbled benzene,N2 bubbled chloroform and N2 bubbled acetone were clarified using a sub-5fs laser pulse. The result showed that the transition energy from the 1Q x states,consisting of the 1Q x(1,0)(π,π*) state(existing at 18800 cm-1 ) and 1Q x(0,0)(π,π*) state(existing at 17800 cm-1 ),to the 1M state of six-coordinated ruthenium complex is lower than that of the five-coordinated ruthenium complex. The intersystem crossing 1Q x(0,0)(π,π*)→ 3(d,π*) in the five-coordinate Ru II(TPP)(CO) in the solution was found to take place in about 1 ps.展开更多
基金by Grant-in-Aid for Scientif ic Research (Category B, No. 18390168) for K Tsukamoto by the Ministry of Education, Culture, Sports, Science and Technology of Japan
文摘AIM: To investigate an association between N -acetyltransferase 2 (NAT2 )-haplotypes/diplotypes and adverse effects in Japanese pulmonary tuberculosis patients. METHODS: We studied 100 patients with pulmonary TB treated with anti-TB drugs including INH. The frequencies and distributions of single nucleotide polymorphisms, haplotypes, and diplotypes of NAT2 were determined by the PCR-restriction fragment length polymorphism method, and the results were compared between TB patients with and without adverse effect, using multivariate logistic regression analysis.RESULTS: Statistical analysis revealed that the frequency of a variant haplotype, NAT2*6A , was signifi cantly increased in TB patients with hepatotoxicity, compared with those without hepatotoxicity [P = 0.001, odds ratio (OR) = 3.535]. By contrast, the frequency of a wild-type (major) haplotype, "NAT2*4", was signif icantly lower in TB patients with hepatotoxicity than those without hepatotoxicity (P < 0.001, OR = 0.265). There was no association between NAT2-haplotypes and skin rash or eosinophilia. CONCLUSION: The present study shows that NAT2 is one of the determinants of anti-TB drug-induced hepatotoxicity. Moreover, the haplotypes, NAT2*4 and NAT2*6A, are useful new biomarkers for predicting anti- TB drug-induced hepatotoxicity.
基金This work was supported in part by the“Materials Research by Information Integration”Initiative(MI2I)project of the Support Program for Starting Up Innovation Hub from Japan Science and Technology Agency(JST)and a Grant-in-Aid for Scientific Research(B)15H02672 from the Japan Society for the Promotion of Science(JSPS)S.W.gratefully acknowledges financial support from JSPS KAKENHI Grant Number JP18K18017+3 种基金K.H.gratefully acknowledges financial support from JSPS KAKENHI Grant Number JP17K17762a Grant-in-Aid for Scientific Research on Innovative Areas(16H06439)and PRESTO(JPMJPR16NA)C.S.gratefully acknowledges financial support from the Ministry of Education and Science of the Russian Federation(Grant 14.Y26.31.0019)J.M.acknowledges partial financial support by JSPS KAKENHI Grant Number JP16K06768.
文摘The use of machine learning in computational molecular design has great potential to accelerate the discovery of innovative materials.However,its practical benefits still remain unproven in real-world applications,particularly in polymer science.We demonstrate the successful discovery of new polymers with high thermal conductivity,inspired by machine-learning-assisted polymer chemistry.This discovery was made by the interplay between machine intelligence trained on a substantially limited amount of polymeric properties data,expertise from laboratory synthesis and advanced technologies for thermophysical property measurements.Using a molecular design algorithm trained to recognize quantitative structure—property relationships with respect to thermal conductivity and other targeted polymeric properties,we identified thousands of promising hypothetical polymers.From these candidates,three were selected for monomer synthesis and polymerization because of their synthetic accessibility and their potential for ease of processing in further applications.The synthesized polymers reached thermal conductivities of 0.18–0.41 W/mK,which are comparable to those of state-of-the-art polymers in non-composite thermo-plastics.
基金supported by a grant from the United States-Israel Binational Science Foundation(BSF 2007052,to W.J.L.and S.W.)by a Postdoctoral Fellowship for Research Abroad from the Japanese Society for the Promotion of Science(awarded to Michitaka Notaguchi).
文摘In plants, the phloem is the component of the vascular system that delivers nutrients and transmits signals from mature leaves to developing sink tissues. Recent studies have identified proteins, mRNA, and small RNA within the phloem sap of several plant species. It is now of considerable interest to elucidate the biological functions of these potential long-distance signal agents, to further our understanding of how plants coordinate their developmental programs at the whole-plant level. In this study, we developed a strategy for the functional analysis of phloem-mobile mRNA by focusing on IAA transcripts, whose mobility has previously been reported in melon (Cucumis melo cv. Hale's Best Jumbo). Indoleacetic acid (IAA) proteins are key transcriptional regulators of auxin signaling, and are involved in a broad range of developmental processes including root development. We used a combination of vasculature-enriched sampling and hetero-grafting techniques to identify IAA18 and IAA28 as phloemmobile transcripts in the model plant Arabidopsis thaliana. Micro-grafting experiments were used to confirm that these IAA transcripts, which are generated in vascular tissues of mature leaves, are then transported into the root system where they negatively regulate lateral root formation. Based on these findings, we present a model in which auxin distribution, in combination with phloem-mobile Aux/IAA transcripts, can determine the sites of auxin action.
基金This study was partially funded by the“Collaboration Research Program of IDEAS”,Chubu University(IDEAS 201603 and IDEAS201702)the CREST Program“Knowledge Discovery by Constructing AgriBigData”(JPMJCR1512)the SICORP Program“Data Science-based Farming Support System for Sustainable Crop Production under Climatic Change”of the Japan Science and Technology Agency.
文摘In orchards, measuring crown characteristics is essential for monitoring the dynamics of tree growth and optimizing farm management. However, it lacks a rapid and reliable method of extracting the features of trees with an irregular crown shape such as trained peach trees. Here, we propose an efficient method of segmenting the individual trees and measuring the crown width and crown projection area (CPA) of peach trees with time-series information, based on gathered images. The images of peach trees were collected by unmanned aerial vehicles in an orchard in Okayama, Japan, and then the digital surface model was generated by using a Structure from Motion (SfM) and Multi-View Stereo (MVS) based software. After individual trees were identified through the use of an adaptive threshold and marker-controlled watershed segmentation in the digital surface model, the crown widths and CPA were calculated, and the accuracy was evaluated against manual delineation and field measurement, respectively. Taking manual delineation of 12 trees as reference, the root-mean-square errors of the proposed method were 0.08 m (R^(2) = 0.99) and 0.15 m (R^(2) = 0.93) for the two orthogonal crown widths, and 3.87 m2 for CPA (R^(2) = 0.89), while those taking field measurement of 44 trees as reference were 0.47 m (R^(2) = 0.91), 0.51 m (R^(2) = 0.74), and 4.96 m2 (R^(2) = 0.88). The change of growth rate of CPA showed that the peach trees grew faster from May to July than from July to September, with a wide variation in relative growth rates among trees. Not only can this method save labour by replacing field measurement, but also it can allow farmers to monitor the growth of orchard trees dynamically.
基金The work at Tokushima University was supported by grants for the Exploratory Research for Advanced Technology(ERATO)MINOSHIMA Intelligent Optical Synthesizer(IOS)Project(JPMJER1304)the Japanese Science and Technology Agency+3 种基金a Grant-in-Aid for Scientific Research(A)(19H00871/26246031)the Ministry of Education,Culture,Sports,Science,and Technology of JapanSubsidy for Regional University and Regional Industry Creation,Cabinet Office,Japan.The work at Beihang University was supported by NSFC(61435002/61521091/61675014/61675015)Fundamental Research Funds for the Central Universities.The authors declare no competing financial interests.
文摘Dual-comb spectroscopy(DCS)is an emerging spectroscopic tool with the potential to simultaneously achieve a broad spectral coverage and ultrahigh spectral resolution with rapid data acquisition.However,the need for two independently stabilized ultrafast lasers significantly hampers the potential application of DCS.We demonstrate mode-resolved DCS in the THz region based on a free-running singlecavity dual-comb fiber laser with the adaptive sampling method.While the use of a free-running single-cavity dual-comb fiber laser eliminates the need for two mode-locked lasers and their frequency control,the adaptive sampling method strongly prevents the degradation of spectroscopic performance caused by the residual timing jitter in the free-running dual-comb laser.Doppler-limit-approaching absorption features with linewidths down to 25 MHz are investigated for low-pressure acetonitrile/air mixed gas by comb-mode-resolved THz spectroscopy.The successful demonstration clearly indicates its great potential for the realization of lowcomplexity,Doppler-limited THz spectroscopy instrumentation.
文摘Strigolactones (SLs) are a novel class of plant hormones and rhizosphere communication signals, although the molecular mechanisms underlying their activities have not yet been fully determined. Nor is their application in agriculture well developed. The importance of plant hormone agonists has been demonstrated in both basic and applied research, and chemicals that mimic strigolactone functions should greatly facilitate strigolactone research. Here, we report our discovery of a new phenoxyfuranone compound, 4-Br debranone (4BD), that shows similar activity to that of the major strigolactone (SL) analog GR24 in many aspects of a biological assay on plants. 4BD strongly inhibited tiller bud outgrowth in the SL-deficient rice mutant d10 at the same concentration as GR24, with no adverse effects, even dur- ing prolonged cultivation. This result was also observed in the Arabidopsis thaliana SL-deficient mutants max1, max3, and max4. However, the application of 4BD to the Arabidopsis SL-insensitive mutant max2 induced no morphological changes in it. The expression of SL biosynthetic genes was also reduced by 4BD treatment, probably via negative feed- back regulation. However, in a seed germination assay on Striga hermonthica, a root parasitic plant, 4BD showed far less activity than GR24. These results suggest that 4BD is the first plant-specific strigolactone mimic.
基金This work was supported by JST-PRESTO“Advanced Materials Informatics through Comprehensive Integration among Theoretical,Experimental,Computational and Data-Centric Sciences”(Grant No.JPMJPR17N4)JST-ERATO“Spin Quantum Rectification Project”(Grant No.JPMJER1402)I.T.is supported in part by C-SPIN,one of six centers of STARnet,a Semiconductor Research Corporation program,sponsored by MARCO and DARPA.
文摘Machine learning is becoming a valuable tool for scientific discovery.Particularly attractive is the application of machine learning methods to the field of materials development,which enables innovations by discovering new and better functional materials.To apply machine learning to actual materials development,close collaboration between scientists and machine learning tools is necessary.However,such collaboration has been so far impeded by the black box nature of many machine learning algorithms.It is often difficult for scientists to interpret the data-driven models from the viewpoint of material science and physics.Here,we demonstrate the development of spin-driven thermoelectric materials with anomalous Nernst effect by using an interpretable machine learning method called factorized asymptotic Bayesian inference hierarchical mixture of experts(FAB/HMEs).Based on prior knowledge of material science and physics,we were able to extract from the interpretable machine learning some surprising correlations and new knowledge about spin-driven thermoelectric materials.Guided by this,we carried out an actual material synthesis that led to the identification of a novel spin-driven thermoelectric material.This material shows the largest thermopower to date.
文摘Magnetically recyclable Au/Co/Fe core-shell nanoparticles (NPs) have been successfully synthesized via a one-step in situ procedure. Transmission electron microscope (TEM), energy dispersive X-ray spectroscopic (EDS), and electron energy-loss spectroscopic (EELS) measurements revealed that the trimetallic Au/Co/Fe NPs have a triple-layered core-shell structure composed of a Au core, a Co-rich inter-layer, and a Fe-rich shell. The Au/Co/Fe core-shell NPs exhibit much higher catalytic activities for hydrolytic dehydrogenation of ammonia borane (NHBBH3, AB) than the monometallic (Au, Co, Fe) or bimetallic (AuCo, AuFe, CoFe) counterparts.
基金National Natural Science Foundation of China (11821404, 12004358, 61725504, U19A2075)Postdoctoral Innovative Talents Support Program(BX20230349)+6 种基金Innovation Program for Quantum Science and Technology (2021ZD0301400, 2021ZD0301200)Anhui Initiative in Quantum Information Technologies(AHY060300)JSPS KAKENHI (17K05082, 18KK0079,19H05156)JSPS PRESTO (JPMJPR20M4)Fundamental Research Funds for the Central Universities(WK2030000085, 202041012, 841912027)Natural Science Foundation of Shandong Province (ZR2021ZD19)Young Talents Project at Ocean University of China(861901013107)。
文摘Entanglement has been recognized as being crucial when implementing various quantum information tasks.Nevertheless, quantifying entanglement for an unknown quantum state requires nonphysical operations or post-processing measurement data. For example, evaluation methods via quantum state tomography require vast amounts of measurement data and likely estimation.
基金This work was financially supported by JST-ERATO(JPMJER1903)Scientific Research(B)(22H02069)Transformative Research Areas(A)(Digitalization-driven Transformative Organic Synthesis(Digi-TOS))(22H05330).T.M.thanks the Naito Foundation for financial support.
文摘γ-Butyrolactone structures are commonly found in various natural products and serve as crucial building blocks in organic synthesis.Consequently,the development of methods for synthesizingγ-butyrolactones has garnered significant interest within the organic synthesis community.In this study,we present a direct and highly efficient approach for the synthesis ofγ-butyrolactones from allylic alcohols.Notably,this study represents the first instance ofγ-butyrolactone synthesis initiated by radical hydrocarboxylation using CO_(2)^(•–),generated from metal formates,followed by cyclization.This two-step process is achieved through the synergistic interaction of photoredox and hydrogen atom transfer(HAT)catalysis,resulting in the production ofγ-butyrolactones with exceptional efficiency.Additionally,when employingα,α-diaryl allylic alcohol derivatives as substrates,the reaction involves 1,2-aryl migration,which occurs concomitantly with CO_(2)^(•–)addition,leading to the formation of 4,5-substituted lactones in a good yield.The artificial force induced reaction(AFIR)method identified the preferred 1,2-aryl migration pathway along with potential byproduct pathways,in which the targeted 1,2-migration was found to be the most plausible pathway.
基金partially supported by a Grant-in-Aid for Scientific Research(KAKENHI)from the Japan Society for the Promotion of Science(JSPS)(grant number 19H05332)。
文摘Heat treatment of metal-organic frameworks(MOFs)has provided a wide variety of functional carbons coordinated with metal compounds.In this study,two kinds of zinc-based MOF(ZMOF),C_(16)H_(10)O_(4)Zn(ZMOF1)and C_(8)H_(4)O_(4)Zn(ZMOF2),were prepared.ZMOF1 and ZMOF2 were carbonized at 1000℃,forming CZMOF1 and CZMOF2,respectively.The specific surface area(S_(BET))of CZMOF2 was~2700 m^(2)g^(−1),much higher than that of CZMOF1(~1300 m^(2)g^(−1)).A supercapacitor electrode based on CZMOF2 achieved specific capacitances of 360,278,and 221 F g^(−1)at 50,250,and 1000 mA g^(−1)in an aqueous electrolyte(H2SO_(4)),respectively,the highest values reported to date for ZMOF-derived electrodes under identical conditions.The practical applicability of the CZMOF-based supercapacitor was verified in non-aqueous electrolytes.The initial capacitance retention was 78%after 100000 charge/discharge cycles at 10 A g^(−1).Crucially,the high capacitance of CZMOF2 arises from pore generation during carbonization.Below 1000℃,pore generation is dominated by the Zn/C ratio of ZMOFs,as carbon atoms reduce the zinc oxides formed during carbonization.Above 1000℃,a high O/C ratio becomes essential for pore generation because the oxygen functional groups are pyrolyzed.These findings will provide insightful information for other metal-based MOFderived multifunctional carbons.
基金supported by National Natural Science Foundation of China(Grant Nos.51973021,52221006,52173275,51932002 and 51903013)Beijing Municipal Health Commission(BJRITO-RDP-2023,PXM 2020_026275_000002 and BMHC-2021-6)+2 种基金National Key Research and Development Program(Grant No.2021YFC2400500)Beijing Jishuitan Hospital Nova Program(Grant Nos.XKXX202115 and XKXX202114)Beijing Outstanding Young Scientist Program(Grant No.BJJWZYJH01201910010024).
文摘miRNAs are important regulators of gene expression and play key roles in the development of cancer, including osteosarcoma. During the development of osteosarcoma, the expression of miR-22 is significantly downregulated, making miR-22 as a promising therapeutic target against osteosarcoma. To design and fabricate efficient delivery carriers of miR-22 into osteosarcoma cells, a hydroxyl-rich reduction-responsive cationic polymeric nanoparticle, TGIC-CA (TC), was developed in this work, which also enhanced the therapeutic effects of Volasertib on osteosarcoma. TC was prepared by the ring-opening reaction between amino and epoxy groups by one-pot method, which had the good complexing ability with nucleic acids, reduction-responsive degradability and gene transfection performance. TC/miR-22 combined with volasertib could inhibit proliferation, migration and promote apoptosis of osteosarcoma cells in vitro. The anti-tumor mechanisms were revealed as TC/ miR-22 and volasertib could inhibit the PI3K/Akt signaling pathway synergistically. Furthermore, this strategy showed outstanding tumor suppression performance in animal models of orthotopic osteosarcoma, especially in patient-derived chemo-resistant and chemo-intolerant patient-derived xenograft (PDX) models, which reduced the risk of tumor lung metastasis and overcame drug resistance. Therefore, it has great potential for efficient treatment of metastasis and drug resistance of osteosarcoma by the strategy of localized, sustained delivery of miR-22 using the cationic nanocarriers combined with non-traditional chemotherapy drugs.
基金supported by JSPS KAKENHI(Nos.18K14056 and 19H00838)JST,PRESTO(No.JPMJPR19T3)+3 种基金Japan.A part of this work was supported by the cooperative research program of“Network Joint Research Center for Materials and Devices”(No.20211069).support of the International Joint Research Promotion Program at Osaka University.G.X.Y.gratefully acknowledges the financial support from the China Scholarship Council(No.201808310132)Y.K.,K.M.,and H.Y.thank the Elements Strategy Initiative of MEXT(No.JPMXP0112101003)Japan.The synchrotron radiation experiments for XAFS measurement were performed at the BL01B1 beamline in SPring-8 with approval from JASRI(Nos.2019B1114 and 2020A1064).
文摘The development of reliable catalysts with both excellent activity and recyclability for carbon dioxide(CO_(2))hydrogenation is challenging.Herein,a ternary hybrid heterogeneous catalyst,involving mononuclear Ru complex,N,P-containing porous organic polymers(POPs),and mesoporous hollow carbon spheres(Ru^(3+)-POPs@MHCS)is reported for CO_(2)hydrogenation to formate.Based on comprehensive structural analyses,we demonstrated that Ru^(3+)-POPs were successfully immobilized within MHCS.The optimized Ru^(3+)-0.5POPs@MHCS catalyst,which was obtained with about 5 wt.%Ru^(3+)and 0.5 mmol POPs polymers confined into 0.3 g MHCS,exhibited high catalytic activity for CO_(2)hydrogenation to formate(turnover number(TON)>1,200 for 24 h under mild reaction conditions(4.0 MPa,120℃))and improved durability,compared to Ru^(3+)catalysts without POPs polymers(Ru^(3+)-MHCS)and unencapsulated MHCS(Ru^(3+)-0.5POPs)catalysts.The improved catalytic performance is attributed to the high surface area and large pore volume of MHCS which favors dispersion and stabilization of Ru^(3+)-POPs.Furthermore,the MHCS and POPs showed high CO_(2)adsorption ability.Ru^(3+)-POPs encapsulated into MHCS reduces the activation energy barrier for CO_(2)hydrogenation to formate.
基金supported by Japan Society for the Promotion of Science KAKENHI(Grant Nos.JP19H05786,JP21H04532,JP21H04618,JP21K20484,JP20H02421,JP22K14143,JP17H01238,and JP17H06094)A.Nakamura and E.Tochigi acknowledge the financial support of JST PRESTO(Grant Nos.JPMJPR199A and JPMJPR1999)X.Fang acknowledges the financial support by the Athene Young Investigator Programme at TU Darmstadt.
文摘Dislocation-mediated plasticity in inorganic semiconductors and oxides has attracted increasing research interest because of the promising mechanical and functional properties tuned by dislocations.In this study,we investigated the effects of light illumination on the dislocation-mediated plasticity in hexagonal wurtzite ZnO,a representative third-generation semiconductor material.A(0001)45o off sample was specially designed to preferentially activate the basal slip on(0001)plane.Three types of nanoindentation tests were performed under four different light conditions(550 nm,334 nm,405 nm,and darkness),including low-load(60μN)pop-in tests,high-load(500μN)nanoindentation tests,and nanoindentation creep tests.The maximum shear stresses at pop-in were found to approximate the theoretical shear strength regardless of the light conditions.The activation volume at pop-ins was calculated to be larger in light than in darkness.Cross-sectional transmission electron microscope images taken from beneath the indentation imprints showed that all indentation-induced dislocations were located beneath the indentation imprint in a thin-plate shape along one basal slip plane.These indentation-induced dislocations could spread much deeper in darkness than in light,revealing the suppressive effect of light on dislocation behavior.An analytical model was adopted to estimate the elastoplastic stress field beneath the indenter.It was found that dislocation glide ceased at a higher stress level in light,indicating the increase in the Peierls barrier under light illumination.Furthermore,nanoindentation creep tests showed the suppression of both indentation depth and creep rate by light.Nanoindentation creep also yielded a larger activation volume in light than in darkness.
基金grants from the Japan Society for the Promotion of Science,the Ministry of Education,Culture,Sports,Science and Technology of Japan,the Japan Science and Technology Agency,the Yamada Science Foundation,the Mitsubishi Foundation (to T.H.).The funders had no role in study design,data collection and analysis,decision to publish,or preparation of the manuscript
文摘Pollen tube guidance is controlled by multiple complex interactions with the female tissues. Here, we show that pollen tubes of Torenia fournieri are regulated by a stylar tissue in a length-dependent manner to receive and respond to attractant LURE peptides secreted from synergid cells. We developed an immunostaining method to visualize LURE peptides bound at the plasma membrane of the tip region of the pollen tube. Using this method, we found that LURE peptides bound specifically to pollen tubes growing through a cut style. The peptides also bound to pollen tubes growing through a shorter style, which were not competent to respond to these peptides. These observations suggested a possibility that acquisition of the LURE peptide reception ability and acquisition of full competency are separable pro- cesses. RNA-Seq suggested that the transcription profile of pollen tubes was affected by both the length of the style and the cultivation period, consistently with physiological changes in binding activity and LURE response ability. The data- base generated from de novo RNA-Seq of Torenia pollen tubes was shown to be useful to identify pollen tube proteins by mass spectrometry. Our studies provide insight and an effective platform for protein identification to understand pollen tube guidance.
文摘A large number of 3D models are created on computers and available for networks. Some content-based retrieval technologies are indispensable to find out particular data from such anonymous datasets. Though several shape retrieval technologies have been developed, little attention has been given to the points on human's sense and impression (as known as Kansei) in the conventional techniques, In this paper, the authors propose a novel method of shape retrieval based on shape impression of human's Kansei. The key to the method is the Gaussian curvature distribution from 3D models as features for shape retrieval. Then it classifies the 3D models by extracted feature and measures similarity among models in storage.
文摘The fabrication of heterostructures of two-dimensional semiconductors with specific bandgaps is an important approach to realizing the full potential of these materials in electronic and optoelectronic devices. Several groups have recently reported the direct growth of lateral and vertical heterostructures based on monolayers of typical semiconducting transition metal dichalcogenides (TMDCs) such as WSe2, MoSe2, WS2, and MoS2. Here, we demonstrate the single-step direct growth of lateral and vertical heterostructures based on bandgap-tunable Mo1-xWxS2 alloy monolayers by the sulfurization of patterned thin films of WO3 and MoO3. These patterned films are capable of generating a wide variety of concentration gradients by the diffusion of transition metals during the crystal growth phase. Under high temperatures, this leads to the formation of monolayer crystals of Mo1-xWxS2 alloys with various compositions and bandgaps, depending on the positions of the crystals on the substrates. Heterostructures of these alloys are obtained through stepwise changes in the ratio of W/Mo within a single domain during low-temperature growth. The stabilization of the monolayer Mo1-xWxS2 alloys, which often degrade even under gentle conditions, was accomplished by coating the alloys with other monolayers. The present findings demonstrate an efficient means of both studying and optimizing the optical and electrical properties of TMDC-based heterostructures to allow use of the materials in future device applications.
基金supported by JST PRESTO Program,MOE ATU Program in NCTU,NSC of Taiwan (Grant No.NSC 98-2112-M-009-001-MY3)
文摘Relaxation of electronic excited-state and vibrational dynamics in the electronic excited state in Ru II(TPP)(CO) [TPP=tetraphenylporphyrin] dissolved in N2 bubbled benzene,O2 bubbled benzene,N2 bubbled chloroform and N2 bubbled acetone were clarified using a sub-5fs laser pulse. The result showed that the transition energy from the 1Q x states,consisting of the 1Q x(1,0)(π,π*) state(existing at 18800 cm-1 ) and 1Q x(0,0)(π,π*) state(existing at 17800 cm-1 ),to the 1M state of six-coordinated ruthenium complex is lower than that of the five-coordinated ruthenium complex. The intersystem crossing 1Q x(0,0)(π,π*)→ 3(d,π*) in the five-coordinate Ru II(TPP)(CO) in the solution was found to take place in about 1 ps.