The tidal triggering of earthquakes has been studied for many years.The discovery of slow earthquakes in the early 2000s,including slow slip,has urged scientists to investigate the tidal responses of these earthquakes...The tidal triggering of earthquakes has been studied for many years.The discovery of slow earthquakes in the early 2000s,including slow slip,has urged scientists to investigate the tidal responses of these earthquakes due to their sensitivity to weak stress perturbations.Previous studies have shown that slow earthquakes correlate with diurnal and semidiurnal tides and seasonal variations in surface loads more clearly than ordinary earthquakes.However,little is known about long-term responses to external stresses.In this paper,based on a widely accepted frictional law for faults,a mechanism is proposed by which nontidal variations in ocean bottom pressure,when combined with tides,pro mote the occurrence of slow earthquakes.Because slow earthquakes accompany a slip on the plate interface,this mechanism allows one to estimate slip modulations.A one-degree-of-freedom slip model is constructed and applied to Ise Bay in the Tonankai region of southwestern Japan,where large-scale ocean mass redistributions have occurred.The model calculated with parameters determined from the observation of tectonic tremors is quantitatively consistent with the slip during 1997-2013 inferred from GNSS data,suggesting that the decrease in the sea-level change in approximately 2006 could cause the accele ration of a slip observed after that.This result implies that the decreases in sea level in approximately 1996 and 2014 could also cause subsequent slip accelerations.These three slip acceleration periods temporally coincide with the increases in background seismicity in a shallower portion of the plate interface.These changes in seismicity are common to shallow earthquakes in the Tokai area,and a similar model can reproduce them.Further studies are expected to reveal causality between shallow earthquakes and long-term slip fluctuations based on modeling that considers changes in the frictional property along the plate interface.展开更多
Three industry-supplied,well-shaped Mo/HZSM-5 catalysts,two binder-added and one binder-free,were tested for the first time in methane dehydroaromatization to benzene at 1073 K and 10000 mL/(g h)in periodic CH4-H2 swi...Three industry-supplied,well-shaped Mo/HZSM-5 catalysts,two binder-added and one binder-free,were tested for the first time in methane dehydroaromatization to benzene at 1073 K and 10000 mL/(g h)in periodic CH4-H2 switch operation mode,and their catalytic performances were compared with those of three self-prepared,binder-free powder Mo/HZSM-5 catalysts.XRD,27Al NMR,SEM,BET and NH3-TPD characterizations of all the catalysts show that the zeolites in the two binder-added catalysts are comparable to those in the three binder-free powder catalysts in crystallinity,crystal size,micropore volume and Brnsted acidity.The test results,on the other hand,show that the catalytic performances of the two binder-added catalysts are worse than those of the four binder-free catalysts on both catalyst mass and zeolite mass bases.Then,TPO and BET measurements of all spent samples were conducted to get a deep insight into the negative effects of binder addition, and the results suggest that the binder additives functioned mainly to enhance the polyaromatization of formed aromatics to coke on their external surfaces and consequently lower the benzene formation activity and selectivity of the catalyst.展开更多
To understand the evolution of stress-induced elastic wave anisotropy,three triaxial experiments were performed on sandstone specimens with bedding orientations parallel,perpendicular,and oblique to the maximum princi...To understand the evolution of stress-induced elastic wave anisotropy,three triaxial experiments were performed on sandstone specimens with bedding orientations parallel,perpendicular,and oblique to the maximum principal stress.P-wave velocities along 64 different directions on each specimen were monitored frequently to understand the anisotropy change at various stress levels by fitting Thomsen’s anisotropy equation.The results show that the elastic wave anisotropy is very sensitive to mechanical loading.Under hydrostatic loading,the magnitude of anisotropy is reduced in all three specimens.However,under deviatoric stress loading,the evolution of anisotropic characteristics(magnitude and orientation of the symmetry axis)is bedding orientation dependent.Anisotropy reversal occurs in specimens with bedding normal/oblique to the maximum principal stress.P-wave anisotropyε0 is linearly related to volumetric strain Sv and dilatancy,indicating that stress-induced redistribution of microcracks has a significant effect on P-wave velocity anisotropy.The closure of initial cracks and pores aligned in the bedding direction contributes to the decrease of the anisotropy.However,opening of new cracks,aligned in the maximum principal direction,accounts for the increase of the anisotropy.The experimental results provide some insights into the microstructural behavior under loading and provide an experimental basis for seismic data interpretation and parameter selection in engineering applications.展开更多
Surface-enhanced resonance Raman scattering(SERRS)has recently attracted great interest in analytical science due toenormous enhancement factors that have decreased the detec-tionli mits of a wide variety of molecules...Surface-enhanced resonance Raman scattering(SERRS)has recently attracted great interest in analytical science due toenormous enhancement factors that have decreased the detec-tionli mits of a wide variety of molecules to the single moleculelevel.The SERRS-electromagnetic(EM)model describessingle-molecule SERRS展开更多
The Earth's sustainable development is threatened by the increasing atmospheric CO_2 level which can be attributed to the imbalance of CO_2 due to the rapid consumption of fossil fuels caused by human activities a...The Earth's sustainable development is threatened by the increasing atmospheric CO_2 level which can be attributed to the imbalance of CO_2 due to the rapid consumption of fossil fuels caused by human activities and the slow absorption and conversion of CO_2 by nature. One of the efficient methods for reconstructing the balance of CO_2 should involve the rapid conversion of CO_2 into fuels and chemicals.The hydrogenation of CO_2 with gaseous hydrogen is currently considered to be the most commercially feasible synthetic route, however, the supply of safe and economical hydrogen sources poses a significant challenge to up-scaling application. Direct utilization of hydrogen from dissociation of water, the most abundant, cheap and clean hydrogen resource, for the reduction of CO_2 would be one of the most promising approaches for CO_2 utilization. This paper provides an overview of the current advances in research on highly efficient reduction of CO_2 or NaHCO_3, a representative compound of CO_2, into formic acid/formate by in situ hydrogen from water dissociation with a metal/metal oxide redox cycle under mild hydrothermal conditions.展开更多
Background:The application of cryopreservation and artificial insemination technology have contributed to the advancement of animal reproduction.However,a substantial proportion of spermatozoa undergoes alterations an...Background:The application of cryopreservation and artificial insemination technology have contributed to the advancement of animal reproduction.However,a substantial proportion of spermatozoa undergoes alterations and loses their fertility during cryopreservation,rendering the frozen-thawed semen impractical for routine use.Cryopreservation is known to reduce sperm lifespan and fertility.Variation in cryosurvival of spermatozoa from different sires and even with the individual sire is common in artificial insemination(AI)centers.Our goal is to improve post-thawed semen quality by optimization of cryopreservation technique through sperm selection prior to cryopreservation process.Results:Our strategy of sperm selection based on rheotaxis and thermotaxis(SSRT)on macrosale in a rotating fluid flow demonstrated the ability to maintain the original pre-freezing structural integrity,viability and biological function related to fertilization competence.This strategy has a positive effect on the cryosurvival and fertilizing abilities of spermatozoa as supported by the improvement on pregnancy rate of Japanese Black heifers and Holstein repeat breeders.This technique protected further sublethal damage to bovine spermatozoa(higher%cryosurvival than the control)and resulted in the improvement of DNA integrity.Prefreeze selected spermatozoa demonstrated slower and controlled capacitation than unprocessed control which is thought to be related to sperm longevity and consequently to appropriate timing during in vivo fertilization.Conclusions:These results provide solid evidence that improvement of post-thawed semen quality by SSRT method is beneficial in terms of cryosurvival,longevity of post-thawed sperm,and optimization of in vivo fertilization,embryo development and calving as supported by the favorable results of field fertility study.展开更多
It is a challenge to thoroughly understand the astonishing difference in catalytic activity between nanogold and bulk gold for some oxidation reactions. In this work,the Au–O interactions in various surroundings were...It is a challenge to thoroughly understand the astonishing difference in catalytic activity between nanogold and bulk gold for some oxidation reactions. In this work,the Au–O interactions in various surroundings were investigated by DFT calculations and compared with the Ag–O interactions. We have found the three points.First,only Au–O bond can be significantly strengthened by the linear O–Au–O structure. Second,the Au–O bond is always stronger than the Ag–O bond when the bonds are embedded in common surroundings. Third,the Au–O bond becomes weaker than the Ag–O bond when the number of neighboring Au atoms becomes large,because the Au–O interactions are suppressed by the presence of neighboring gold atoms. The origin of these three points can be attributed to wider spatial extension of d orbitals of gold,induced by strong relativistic effects. The strong relativistic effects make nanogold with smaller coordinate numbers highly active due to the ease in forming strong Au–O bonds,especially for the O–Au–O bond,whereas gold atoms in bulk with larger coordination numbers chemically inert due to the strong suppression by neighboring gold atoms destabilizing the O–Au–O bond.展开更多
Ti-Cu films with different Cu concentrations were fabricated by high-power pulsed magnetron sputtering(HPPMS) to release copper ions and catalyze NO to improve the blood compatibility. The Cu concentrations of films w...Ti-Cu films with different Cu concentrations were fabricated by high-power pulsed magnetron sputtering(HPPMS) to release copper ions and catalyze NO to improve the blood compatibility. The Cu concentrations of films were 25.7 at% and 68.8 at%. Pure Ti films were also fabricated. Copper release, catalytic release of nitric oxide(NO), and blood platelet adhesion of Ti-Cu films were studied. Ti-Cu films released copper ions in PBS solution and more Cu ions were released from films with 68.8 at% Cu. Ti-Cu films had excellent ability of catalytical decomposition of exogenous donor S-nitroso-N-acetyl-DL-penicillamine(SNAP) and as a result, nitric oxide(NO) was generated. The NO generation catalyzed by Ti-Cu films was significantly higher than that by pure Ti films. This was more eminent in the Ti-Cu films with 68.8 at% Cu. The platelet adhesion and activation of Ti-Cu films were significantly inhibited compared to that of pure Ti films in the presence of SNAP. The Ti-Cu film fabricated by HPPMS showed the ability of releasing Cu ions to catalyze SNAP to generate NO to inhibit platelet adhesion and activation.展开更多
This paper described the use of fy ash for soil amelioration of acidic soils to promote plant growth.In mining sites,acid sulfate soils/rocks,which contain sulfde minerals(e.g.pyrite FeS_(2)),have appeared as a result...This paper described the use of fy ash for soil amelioration of acidic soils to promote plant growth.In mining sites,acid sulfate soils/rocks,which contain sulfde minerals(e.g.pyrite FeS_(2)),have appeared as a result of overburden excavation.The excessively acidic condition inhibits plant growth due to the dissolution of harmful elements,such as Al,Fe,and Mn.Fly ash,an alkaline byproduct of coal combustion generated in thermal power plants is expected to be adopted to ameliorate acidic soils.However,the mixing ratio of fy ash must be considered because excessive addition of fy ash can have a negative impact on plant growth due to its physical/chemical properties.The pot trials using Acacia mangium demonstrate the evolution of plant growth with a 5%–10%addition of fy ash into acidic soil.When the acidic soil has a high potential for metal dissolution,the metal ions leached from the acidic soil are large,making it difcult to improve plant growth due to osmotic and ionic stress.This work suggests that the efects of fy ash on metal ions leached from the soil have to be considered for the amelioration of acidic soil.展开更多
We herein report our studies into the effects of microwave irradiation on the solvent-free esterification of L-leucine with alcohols. In the absence of solvent, microwave irradiation accelerated the reaction compared ...We herein report our studies into the effects of microwave irradiation on the solvent-free esterification of L-leucine with alcohols. In the absence of solvent, microwave irradiation accelerated the reaction compared to conventional oil bath heating. Measurement of the dielectric properties under the reaction conditions revealed that the high dielectric loss factor of the reaction mixture containing L-leucine, n-butanol, and a p-toluene sulfonic acid catalyst could be attributed to the acceleration of the reaction. The depth of microwave penetration into the reaction mixture as derived from the in-situ measurement of the dielectric properties was ~13 mm, which suggested that a thinner reaction vessel was favorable for the esterification of L-leucine. In addition to the batch reaction using a desktop microwave reactor, two types of flow reaction were also performed using a desktop tubular reactor and a semi-bench-scale tubular reactor. These flow reactions also exhibited high performances, thus allowing the scale-up of this reaction system for industrial use.展开更多
Nanotechnology has revolutionized cancer drug delivery,and recent research continues to focus on the development of“one-size-fits-all,”i.e.,“all-in-one”delivery nanovehicles.Although nanomedicines can address sign...Nanotechnology has revolutionized cancer drug delivery,and recent research continues to focus on the development of“one-size-fits-all,”i.e.,“all-in-one”delivery nanovehicles.Although nanomedicines can address significant shortcomings of conventional therapy,biological barriers remain a challenge in their delivery and accumulation at diseased sites.To achieve long circulation time,immune evasion,and targeted accumulation,conventional nanocarriers need modifications,e.g.,PEGylation,peptide/aptamer attachment,etc.One such modification is a biomimetic coating using cell membrane(CM),which can offer long circulation or targeting,or both.This top-down CM coating process is facile and can provide some advantageous features over surface modification by synthetic polymers.Herein,an overview is provided on the engineering of CM camouflaged polymer nanoparticles.A short section on CM and the development of CM coating technology has been provided.Detailed description of the preparation and characterization of CM camouflaged polymer NPs and their applications in cancer treatment has been reported.A brief comparison between CM coating and PEGylation has been highlighted.Various targeting approaches to achieve tumor-specific delivery of CM coated NPs have been summarized here.Overall,this review will give the readers a nice picture of CM coated polymer NPs,along with their opportunities and challenges.展开更多
By using psychological and physiological indicators, the effects on the body of three-dimensional (3D) movies containing improper settings were evaluated with 139 university students. The experiment consisted of two s...By using psychological and physiological indicators, the effects on the body of three-dimensional (3D) movies containing improper settings were evaluated with 139 university students. The experiment consisted of two sessions: 1) a 3D movie containing improper 3D settings was compared with a 2D movie containing only the rightside images presented to both eyes, and 2) the original 3D movie was compared with the same 3D movie altered to contain improper 3D settings. The results of this experiment demonstrated clear deterioration of the subjective psychological indicators (degree of motion sickness after watching the movies and comfort level at 1-min intervals during the movie) with respect to the 3D movie containing improper settings. On the other hand, the physiological indicators (LF/HF ratio indicating the status of the autonomic nervous system) changed as a result of watching a 3D movie, but were unaffected by the presence or absence of improper 3D settings.展开更多
The procedure to measure liposome in aqueous solution has been examined using atomic force microscope (AFM). We concluded a chemical modified silicon wafer (substrate for AFM observation of liposome) with 3-aminopropy...The procedure to measure liposome in aqueous solution has been examined using atomic force microscope (AFM). We concluded a chemical modified silicon wafer (substrate for AFM observation of liposome) with 3-aminopropyltrieth-oxysilane (APTES) which enabled us to scan anionic liposome softly in water because they were keeping structures as vesicles and stably adsorbed on the substrate by electrostatic force. From captured AFM topographic images, we counted the amount of liposome and analyzed the distribution of mean diameters, which were corrected by an approximated curve of the tip shape. We discussed the method of effective evaluation as practical analysis and its problems for robust analysis.展开更多
Brain-derived neurotrophic factor (BDNF) is a neurotrophin that elicits neuronal survival and differentiation, synaptic transmission, and the modulation of synaptic plasticity. The biological actions of BDNF are media...Brain-derived neurotrophic factor (BDNF) is a neurotrophin that elicits neuronal survival and differentiation, synaptic transmission, and the modulation of synaptic plasticity. The biological actions of BDNF are mediated via two distinct receptors: the high-affinity tropomyosin-related kinase B (TrkB) receptor and the low-affinity p75 neurotrophin receptor (p75NTR). Recent findings regarding the actions and mechanisms of BDNF are reviewed here. Activity-dependent synaptic plasticity, as exemplified by long-term potentiation (LTP) and long-term depression (LTD), underlies the cellular mechanism of learning and memory. An accumulating body of evidence shows that BDNF modulates synaptic plasticity. This function requires extracellular neurotrophin release, synaptic activity-dependent local protein synthesis. In addition, a precursor of BDNF, proBDNF, is emerging as a new ligand with biological activities that are distinct from those of BDNF. The proteolytic cleavage of proBDNF is also proposed as a mechanism that determines the direction of BDNF actions. This review discusses the post-translational processing of proBDNF, the modulatory roles of the human BDNF polymorphism Val66Met, recent reports of the novel mechanisms of BDNF expression, and clinical reports showing the roles of BDNF in the blood. Taken together, these data provide new insights into the biological roles of BDNF and its related molecules in the central nervous system.展开更多
Aim: Cognitive dysfunction and negative symptoms interfere social participation in patients with schizophrenia. Cognitive remediation has proven effective for cognitive deficits. While there are few effective treatmen...Aim: Cognitive dysfunction and negative symptoms interfere social participation in patients with schizophrenia. Cognitive remediation has proven effective for cognitive deficits. While there are few effective treatments for the negative symptoms of schizophrenia, music therapy is expected to ameliorate negative symptoms. With the goal of improving both cognitive dysfunction and negative symptoms, we originally developed a program of Music Therapy incorporated into Cognitive Remediation (MTCR). We introduce the MTCR program and our preliminary results of conducting MTCR in patients with schizophrenia. Methods: The program was based on the NEAR (neuropsychological educational approach to cognitive remediation) program. The MTCR program uses instrumental performances and ensemble vocal performances to train cognitive functions, which consists of 30 sessions in total, with each session being 60 minutes long (45 minutes of music, 15 minutes of verbal session). The participants attended sessions semiweekly in groups of fewer than 12 members. We measured the participants’ symptoms twice, before the intervention and after the final session. For both measurements, we used the BACS and BPRS. Thirty-six individuals (26 men, 10 women;average age of 42.4 years) with schizophrenia participated in this study. They participated in an average of 28.2 sessions. Results: BACS total scores (p Conclusions: The present study demonstrated that MTCR program can improve both cognitive dysfunction and negative symptoms of patients with schizophrenia, which implies that it can also potentially facilitate the social participation of such patients.展开更多
Crystallization of enzymes in presence of impurities is important for clarifying the role of enzymes in natural world. Although it is proposed that impurities inhibit nucleation of enzyme crystallization, details are ...Crystallization of enzymes in presence of impurities is important for clarifying the role of enzymes in natural world. Although it is proposed that impurities inhibit nucleation of enzyme crystallization, details are unclear. In this study, crystallization of cellobiohydrolase from Aspergillus niger was investigated by dynamic and time-resolved static light scattering using cellobiose as an impurity. We aimed to clarify how cellobiose inhibits cellobiohydrolase crystallization and to crystallize cellobiohydrolase in concentrated cellobiose without using seeds. The contribution of attractive forces to total intermolecular interactions of cellobiohydrolase monomers increased with the molar ratio of cellobiose/cellobiohydrolase (R(cb/ce)). Association dynamics of cellobiohydrolase using lithium sulfate, however, showed that the initial aggregation rate decreased with an increase in R(cb/ce). Because binding sites of cellobioses to cellobiohydrolase molecules differed from those for the growth of protein crystals, the binding of cellobioses would increase the chemical potential of the cellobiohydrolase monomers, which gradually reduced supersaturation for growth as the aggregate size increased. This result was in contrast with the conventional idea that cellobiose inhibits the nucleation of cellobiohydrolase crystals. Gentle agitation of cellobiose-containing cellobiohydrolase solutions during sitting-drop vapor-diffusion growth resulted in the growth of cellobiohydrolase single crystals for all R(cb/ce) conditions without using seeds.展开更多
For the assessment of the carbon dioxide (CO2) storage potential of water-filled reservoir rocks (i.e., saline aquifers), it should be first important step for a thorough understanding of the effect of water content o...For the assessment of the carbon dioxide (CO2) storage potential of water-filled reservoir rocks (i.e., saline aquifers), it should be first important step for a thorough understanding of the effect of water content on CO2/water/rock interactions during CO2 injection. The purpose of this study is to examine the CO2 sorption amount for Kimachi sandstone and Berea sandstone at different water content using the manometric method at temperature of 50?C and pressures of up to 20 MPa. Our results document that a significant quantity of CO2 was sorbed on the two types of sandstone on all water-saturated bases, which corresponded to the amount adsorbed on the air-dry basis. Also, all the wet samples had significantly higher sorption capacity than the theoretical values calculated from the solubility model based on dissolution of CO2 in pore water and the pore-filling model, which assumes that the pore volume unoccupied by water is filled with CO2. Furthermore, the observations indicated a certain degree of correlation between the sorbed amount and the water content, except at pressures below the critical point for Berea sandstone. This investigation points out that CO2 sorption is a possible mechanism in CO2 geological storage even under water-saturated conditions and that the mechanism of sorption on silica and silicate minerals plays an essential role in the reliable and accurate estimation of the CO2 storage capacity of water-saturated reservoirs.展开更多
Quantum dots are the nanoparticles that are recently emerging as an alternative to organic fluorescence probes in cell biology and biomedicine,and have several predictive advantages.These include their i)broad absorpt...Quantum dots are the nanoparticles that are recently emerging as an alternative to organic fluorescence probes in cell biology and biomedicine,and have several predictive advantages.These include their i)broad absorption spectra allowing visualization with single light source,ii)exceptional photo-stability allowing long term studies and iii)narrow and symmetrical emission spectrum that is controlled by their size and material composition.These unique properties allow simultaneous excitation of different size of quantum dots with a single excitation light source,their simultaneous resolution and visualization as different colors.At present there are only a few studies that have tested quantum dots in cellular imaging.We describe here the use of quantum dots in mortalin imaging of normal and cancer cells.Mortalin staining pattern with quantum dots in both normal and cancer cells mimicked those obtained with organic florescence probes and were considerably stable.展开更多
The demand for efficient and environmentally-benign electrocatalysts that help availably harness the renewable energy resources is growing rapidly. In recent years, increasing insights into the design of water electro...The demand for efficient and environmentally-benign electrocatalysts that help availably harness the renewable energy resources is growing rapidly. In recent years, increasing insights into the design of water electrolysers, fuel cells, and metal–air batteries emerge in response to the need for developing sustainable energy carriers, in which the oxygen evolution reaction and the oxygen reduction reaction play key roles. However, both reactions suffer from sluggish kinetics that restricts the reactivity. Therefore, it is vital to probe into the structure of the catalysts to exploit high-performance bifunctional oxygen electrocatalysts. Spinel-type catalysts are a class of materials with advantages of versatility, low toxicity, low expense, high abundance, flexible ion arrangement, and multivalence structure. In this review, we afford a basic overview of spinel-type materials and then introduce the relevant theoretical principles for electrocatalytic activity, following that we shed light on the structure–property relationship strategies for spinel-type catalysts including electronic structure, microstructure, phase and composition regulation,and coupling with electrically conductive supports. We elaborate the relationship between structure and property, in order to provide some insights into the design of spinel-type bifunctional oxygen electrocatalysts.展开更多
基金partly supported by JSPS KAKENHI Grant Numbers JP16H02219, JP21H01187, JP21H05204, JP21K14022 and JP21H05203JST Grant Number JPMJMI18A1。
文摘The tidal triggering of earthquakes has been studied for many years.The discovery of slow earthquakes in the early 2000s,including slow slip,has urged scientists to investigate the tidal responses of these earthquakes due to their sensitivity to weak stress perturbations.Previous studies have shown that slow earthquakes correlate with diurnal and semidiurnal tides and seasonal variations in surface loads more clearly than ordinary earthquakes.However,little is known about long-term responses to external stresses.In this paper,based on a widely accepted frictional law for faults,a mechanism is proposed by which nontidal variations in ocean bottom pressure,when combined with tides,pro mote the occurrence of slow earthquakes.Because slow earthquakes accompany a slip on the plate interface,this mechanism allows one to estimate slip modulations.A one-degree-of-freedom slip model is constructed and applied to Ise Bay in the Tonankai region of southwestern Japan,where large-scale ocean mass redistributions have occurred.The model calculated with parameters determined from the observation of tectonic tremors is quantitatively consistent with the slip during 1997-2013 inferred from GNSS data,suggesting that the decrease in the sea-level change in approximately 2006 could cause the accele ration of a slip observed after that.This result implies that the decreases in sea level in approximately 1996 and 2014 could also cause subsequent slip accelerations.These three slip acceleration periods temporally coincide with the increases in background seismicity in a shallower portion of the plate interface.These changes in seismicity are common to shallow earthquakes in the Tokai area,and a similar model can reproduce them.Further studies are expected to reveal causality between shallow earthquakes and long-term slip fluctuations based on modeling that considers changes in the frictional property along the plate interface.
文摘Three industry-supplied,well-shaped Mo/HZSM-5 catalysts,two binder-added and one binder-free,were tested for the first time in methane dehydroaromatization to benzene at 1073 K and 10000 mL/(g h)in periodic CH4-H2 switch operation mode,and their catalytic performances were compared with those of three self-prepared,binder-free powder Mo/HZSM-5 catalysts.XRD,27Al NMR,SEM,BET and NH3-TPD characterizations of all the catalysts show that the zeolites in the two binder-added catalysts are comparable to those in the three binder-free powder catalysts in crystallinity,crystal size,micropore volume and Brnsted acidity.The test results,on the other hand,show that the catalytic performances of the two binder-added catalysts are worse than those of the four binder-free catalysts on both catalyst mass and zeolite mass bases.Then,TPO and BET measurements of all spent samples were conducted to get a deep insight into the negative effects of binder addition, and the results suggest that the binder additives functioned mainly to enhance the polyaromatization of formed aromatics to coke on their external surfaces and consequently lower the benzene formation activity and selectivity of the catalyst.
基金The research was partially supported by the National Natural Science Foundation of China(Grant Nos.41902297,41872210)the Natural Science Foundation of Hubei Province(Grant No.2018CFB292)Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences(Grant No.Z017006).
文摘To understand the evolution of stress-induced elastic wave anisotropy,three triaxial experiments were performed on sandstone specimens with bedding orientations parallel,perpendicular,and oblique to the maximum principal stress.P-wave velocities along 64 different directions on each specimen were monitored frequently to understand the anisotropy change at various stress levels by fitting Thomsen’s anisotropy equation.The results show that the elastic wave anisotropy is very sensitive to mechanical loading.Under hydrostatic loading,the magnitude of anisotropy is reduced in all three specimens.However,under deviatoric stress loading,the evolution of anisotropic characteristics(magnitude and orientation of the symmetry axis)is bedding orientation dependent.Anisotropy reversal occurs in specimens with bedding normal/oblique to the maximum principal stress.P-wave anisotropyε0 is linearly related to volumetric strain Sv and dilatancy,indicating that stress-induced redistribution of microcracks has a significant effect on P-wave velocity anisotropy.The closure of initial cracks and pores aligned in the bedding direction contributes to the decrease of the anisotropy.However,opening of new cracks,aligned in the maximum principal direction,accounts for the increase of the anisotropy.The experimental results provide some insights into the microstructural behavior under loading and provide an experimental basis for seismic data interpretation and parameter selection in engineering applications.
文摘Surface-enhanced resonance Raman scattering(SERRS)has recently attracted great interest in analytical science due toenormous enhancement factors that have decreased the detec-tionli mits of a wide variety of molecules to the single moleculelevel.The SERRS-electromagnetic(EM)model describessingle-molecule SERRS
基金the financial support of the National Natural Science Foundation of China (Nos. 21277091 and 51472159)the State Key Program of National Natural Science Foundation of China (No. 21436007)+1 种基金the Key Basic Research Projects of Science and Technology Commission of Shanghai (No. 14JC1403100)the Chenxing-SMG Young Scholar Project of Shanghai Jiao Tong University
文摘The Earth's sustainable development is threatened by the increasing atmospheric CO_2 level which can be attributed to the imbalance of CO_2 due to the rapid consumption of fossil fuels caused by human activities and the slow absorption and conversion of CO_2 by nature. One of the efficient methods for reconstructing the balance of CO_2 should involve the rapid conversion of CO_2 into fuels and chemicals.The hydrogenation of CO_2 with gaseous hydrogen is currently considered to be the most commercially feasible synthetic route, however, the supply of safe and economical hydrogen sources poses a significant challenge to up-scaling application. Direct utilization of hydrogen from dissociation of water, the most abundant, cheap and clean hydrogen resource, for the reduction of CO_2 would be one of the most promising approaches for CO_2 utilization. This paper provides an overview of the current advances in research on highly efficient reduction of CO_2 or NaHCO_3, a representative compound of CO_2, into formic acid/formate by in situ hydrogen from water dissociation with a metal/metal oxide redox cycle under mild hydrothermal conditions.
基金supported by the Ministry of Agriculture,Forestry and Fisheries,Japan(MAFF)under the project name“Development of technology for enhancement of livestock lifetime productivity by improving fertility through assisted reproduction”the JSPS KAKENHI(15H04585).
文摘Background:The application of cryopreservation and artificial insemination technology have contributed to the advancement of animal reproduction.However,a substantial proportion of spermatozoa undergoes alterations and loses their fertility during cryopreservation,rendering the frozen-thawed semen impractical for routine use.Cryopreservation is known to reduce sperm lifespan and fertility.Variation in cryosurvival of spermatozoa from different sires and even with the individual sire is common in artificial insemination(AI)centers.Our goal is to improve post-thawed semen quality by optimization of cryopreservation technique through sperm selection prior to cryopreservation process.Results:Our strategy of sperm selection based on rheotaxis and thermotaxis(SSRT)on macrosale in a rotating fluid flow demonstrated the ability to maintain the original pre-freezing structural integrity,viability and biological function related to fertilization competence.This strategy has a positive effect on the cryosurvival and fertilizing abilities of spermatozoa as supported by the improvement on pregnancy rate of Japanese Black heifers and Holstein repeat breeders.This technique protected further sublethal damage to bovine spermatozoa(higher%cryosurvival than the control)and resulted in the improvement of DNA integrity.Prefreeze selected spermatozoa demonstrated slower and controlled capacitation than unprocessed control which is thought to be related to sperm longevity and consequently to appropriate timing during in vivo fertilization.Conclusions:These results provide solid evidence that improvement of post-thawed semen quality by SSRT method is beneficial in terms of cryosurvival,longevity of post-thawed sperm,and optimization of in vivo fertilization,embryo development and calving as supported by the favorable results of field fertility study.
基金supported by Grant-in-Aid for Specially Promoted Research Grant no.19001005 from the Ministry of Education,Culture,Sports,Science and Technology of Japan (MEXT)supported by the Management Expenses Grants for National Universities Corporations from MEXTJapan Science and Technology Agency (JST),Core Research for Evolutional Science and Technology (CREST)
文摘It is a challenge to thoroughly understand the astonishing difference in catalytic activity between nanogold and bulk gold for some oxidation reactions. In this work,the Au–O interactions in various surroundings were investigated by DFT calculations and compared with the Ag–O interactions. We have found the three points.First,only Au–O bond can be significantly strengthened by the linear O–Au–O structure. Second,the Au–O bond is always stronger than the Ag–O bond when the bonds are embedded in common surroundings. Third,the Au–O bond becomes weaker than the Ag–O bond when the number of neighboring Au atoms becomes large,because the Au–O interactions are suppressed by the presence of neighboring gold atoms. The origin of these three points can be attributed to wider spatial extension of d orbitals of gold,induced by strong relativistic effects. The strong relativistic effects make nanogold with smaller coordinate numbers highly active due to the ease in forming strong Au–O bonds,especially for the O–Au–O bond,whereas gold atoms in bulk with larger coordination numbers chemically inert due to the strong suppression by neighboring gold atoms destabilizing the O–Au–O bond.
基金Funded by the National Natural Science Foundation of China(No.31300787)the National Natural Science Foundation of China China Academy of Engineering Physics(NSAF No.U1330113)+1 种基金the Overseas Famous Teacher Program of Chinese Education Ministry(MS2010XNJT070)the Qingmiao Plan of SWJTU 2015(No.A0920502051517-6)
文摘Ti-Cu films with different Cu concentrations were fabricated by high-power pulsed magnetron sputtering(HPPMS) to release copper ions and catalyze NO to improve the blood compatibility. The Cu concentrations of films were 25.7 at% and 68.8 at%. Pure Ti films were also fabricated. Copper release, catalytic release of nitric oxide(NO), and blood platelet adhesion of Ti-Cu films were studied. Ti-Cu films released copper ions in PBS solution and more Cu ions were released from films with 68.8 at% Cu. Ti-Cu films had excellent ability of catalytical decomposition of exogenous donor S-nitroso-N-acetyl-DL-penicillamine(SNAP) and as a result, nitric oxide(NO) was generated. The NO generation catalyzed by Ti-Cu films was significantly higher than that by pure Ti films. This was more eminent in the Ti-Cu films with 68.8 at% Cu. The platelet adhesion and activation of Ti-Cu films were significantly inhibited compared to that of pure Ti films in the presence of SNAP. The Ti-Cu film fabricated by HPPMS showed the ability of releasing Cu ions to catalyze SNAP to generate NO to inhibit platelet adhesion and activation.
文摘This paper described the use of fy ash for soil amelioration of acidic soils to promote plant growth.In mining sites,acid sulfate soils/rocks,which contain sulfde minerals(e.g.pyrite FeS_(2)),have appeared as a result of overburden excavation.The excessively acidic condition inhibits plant growth due to the dissolution of harmful elements,such as Al,Fe,and Mn.Fly ash,an alkaline byproduct of coal combustion generated in thermal power plants is expected to be adopted to ameliorate acidic soils.However,the mixing ratio of fy ash must be considered because excessive addition of fy ash can have a negative impact on plant growth due to its physical/chemical properties.The pot trials using Acacia mangium demonstrate the evolution of plant growth with a 5%–10%addition of fy ash into acidic soil.When the acidic soil has a high potential for metal dissolution,the metal ions leached from the acidic soil are large,making it difcult to improve plant growth due to osmotic and ionic stress.This work suggests that the efects of fy ash on metal ions leached from the soil have to be considered for the amelioration of acidic soil.
文摘We herein report our studies into the effects of microwave irradiation on the solvent-free esterification of L-leucine with alcohols. In the absence of solvent, microwave irradiation accelerated the reaction compared to conventional oil bath heating. Measurement of the dielectric properties under the reaction conditions revealed that the high dielectric loss factor of the reaction mixture containing L-leucine, n-butanol, and a p-toluene sulfonic acid catalyst could be attributed to the acceleration of the reaction. The depth of microwave penetration into the reaction mixture as derived from the in-situ measurement of the dielectric properties was ~13 mm, which suggested that a thinner reaction vessel was favorable for the esterification of L-leucine. In addition to the batch reaction using a desktop microwave reactor, two types of flow reaction were also performed using a desktop tubular reactor and a semi-bench-scale tubular reactor. These flow reactions also exhibited high performances, thus allowing the scale-up of this reaction system for industrial use.
文摘Nanotechnology has revolutionized cancer drug delivery,and recent research continues to focus on the development of“one-size-fits-all,”i.e.,“all-in-one”delivery nanovehicles.Although nanomedicines can address significant shortcomings of conventional therapy,biological barriers remain a challenge in their delivery and accumulation at diseased sites.To achieve long circulation time,immune evasion,and targeted accumulation,conventional nanocarriers need modifications,e.g.,PEGylation,peptide/aptamer attachment,etc.One such modification is a biomimetic coating using cell membrane(CM),which can offer long circulation or targeting,or both.This top-down CM coating process is facile and can provide some advantageous features over surface modification by synthetic polymers.Herein,an overview is provided on the engineering of CM camouflaged polymer nanoparticles.A short section on CM and the development of CM coating technology has been provided.Detailed description of the preparation and characterization of CM camouflaged polymer NPs and their applications in cancer treatment has been reported.A brief comparison between CM coating and PEGylation has been highlighted.Various targeting approaches to achieve tumor-specific delivery of CM coated NPs have been summarized here.Overall,this review will give the readers a nice picture of CM coated polymer NPs,along with their opportunities and challenges.
文摘By using psychological and physiological indicators, the effects on the body of three-dimensional (3D) movies containing improper settings were evaluated with 139 university students. The experiment consisted of two sessions: 1) a 3D movie containing improper 3D settings was compared with a 2D movie containing only the rightside images presented to both eyes, and 2) the original 3D movie was compared with the same 3D movie altered to contain improper 3D settings. The results of this experiment demonstrated clear deterioration of the subjective psychological indicators (degree of motion sickness after watching the movies and comfort level at 1-min intervals during the movie) with respect to the 3D movie containing improper settings. On the other hand, the physiological indicators (LF/HF ratio indicating the status of the autonomic nervous system) changed as a result of watching a 3D movie, but were unaffected by the presence or absence of improper 3D settings.
文摘The procedure to measure liposome in aqueous solution has been examined using atomic force microscope (AFM). We concluded a chemical modified silicon wafer (substrate for AFM observation of liposome) with 3-aminopropyltrieth-oxysilane (APTES) which enabled us to scan anionic liposome softly in water because they were keeping structures as vesicles and stably adsorbed on the substrate by electrostatic force. From captured AFM topographic images, we counted the amount of liposome and analyzed the distribution of mean diameters, which were corrected by an approximated curve of the tip shape. We discussed the method of effective evaluation as practical analysis and its problems for robust analysis.
文摘Brain-derived neurotrophic factor (BDNF) is a neurotrophin that elicits neuronal survival and differentiation, synaptic transmission, and the modulation of synaptic plasticity. The biological actions of BDNF are mediated via two distinct receptors: the high-affinity tropomyosin-related kinase B (TrkB) receptor and the low-affinity p75 neurotrophin receptor (p75NTR). Recent findings regarding the actions and mechanisms of BDNF are reviewed here. Activity-dependent synaptic plasticity, as exemplified by long-term potentiation (LTP) and long-term depression (LTD), underlies the cellular mechanism of learning and memory. An accumulating body of evidence shows that BDNF modulates synaptic plasticity. This function requires extracellular neurotrophin release, synaptic activity-dependent local protein synthesis. In addition, a precursor of BDNF, proBDNF, is emerging as a new ligand with biological activities that are distinct from those of BDNF. The proteolytic cleavage of proBDNF is also proposed as a mechanism that determines the direction of BDNF actions. This review discusses the post-translational processing of proBDNF, the modulatory roles of the human BDNF polymorphism Val66Met, recent reports of the novel mechanisms of BDNF expression, and clinical reports showing the roles of BDNF in the blood. Taken together, these data provide new insights into the biological roles of BDNF and its related molecules in the central nervous system.
文摘Aim: Cognitive dysfunction and negative symptoms interfere social participation in patients with schizophrenia. Cognitive remediation has proven effective for cognitive deficits. While there are few effective treatments for the negative symptoms of schizophrenia, music therapy is expected to ameliorate negative symptoms. With the goal of improving both cognitive dysfunction and negative symptoms, we originally developed a program of Music Therapy incorporated into Cognitive Remediation (MTCR). We introduce the MTCR program and our preliminary results of conducting MTCR in patients with schizophrenia. Methods: The program was based on the NEAR (neuropsychological educational approach to cognitive remediation) program. The MTCR program uses instrumental performances and ensemble vocal performances to train cognitive functions, which consists of 30 sessions in total, with each session being 60 minutes long (45 minutes of music, 15 minutes of verbal session). The participants attended sessions semiweekly in groups of fewer than 12 members. We measured the participants’ symptoms twice, before the intervention and after the final session. For both measurements, we used the BACS and BPRS. Thirty-six individuals (26 men, 10 women;average age of 42.4 years) with schizophrenia participated in this study. They participated in an average of 28.2 sessions. Results: BACS total scores (p Conclusions: The present study demonstrated that MTCR program can improve both cognitive dysfunction and negative symptoms of patients with schizophrenia, which implies that it can also potentially facilitate the social participation of such patients.
文摘Crystallization of enzymes in presence of impurities is important for clarifying the role of enzymes in natural world. Although it is proposed that impurities inhibit nucleation of enzyme crystallization, details are unclear. In this study, crystallization of cellobiohydrolase from Aspergillus niger was investigated by dynamic and time-resolved static light scattering using cellobiose as an impurity. We aimed to clarify how cellobiose inhibits cellobiohydrolase crystallization and to crystallize cellobiohydrolase in concentrated cellobiose without using seeds. The contribution of attractive forces to total intermolecular interactions of cellobiohydrolase monomers increased with the molar ratio of cellobiose/cellobiohydrolase (R(cb/ce)). Association dynamics of cellobiohydrolase using lithium sulfate, however, showed that the initial aggregation rate decreased with an increase in R(cb/ce). Because binding sites of cellobioses to cellobiohydrolase molecules differed from those for the growth of protein crystals, the binding of cellobioses would increase the chemical potential of the cellobiohydrolase monomers, which gradually reduced supersaturation for growth as the aggregate size increased. This result was in contrast with the conventional idea that cellobiose inhibits the nucleation of cellobiohydrolase crystals. Gentle agitation of cellobiose-containing cellobiohydrolase solutions during sitting-drop vapor-diffusion growth resulted in the growth of cellobiohydrolase single crystals for all R(cb/ce) conditions without using seeds.
文摘For the assessment of the carbon dioxide (CO2) storage potential of water-filled reservoir rocks (i.e., saline aquifers), it should be first important step for a thorough understanding of the effect of water content on CO2/water/rock interactions during CO2 injection. The purpose of this study is to examine the CO2 sorption amount for Kimachi sandstone and Berea sandstone at different water content using the manometric method at temperature of 50?C and pressures of up to 20 MPa. Our results document that a significant quantity of CO2 was sorbed on the two types of sandstone on all water-saturated bases, which corresponded to the amount adsorbed on the air-dry basis. Also, all the wet samples had significantly higher sorption capacity than the theoretical values calculated from the solubility model based on dissolution of CO2 in pore water and the pore-filling model, which assumes that the pore volume unoccupied by water is filled with CO2. Furthermore, the observations indicated a certain degree of correlation between the sorbed amount and the water content, except at pressures below the critical point for Berea sandstone. This investigation points out that CO2 sorption is a possible mechanism in CO2 geological storage even under water-saturated conditions and that the mechanism of sorption on silica and silicate minerals plays an essential role in the reliable and accurate estimation of the CO2 storage capacity of water-saturated reservoirs.
文摘Quantum dots are the nanoparticles that are recently emerging as an alternative to organic fluorescence probes in cell biology and biomedicine,and have several predictive advantages.These include their i)broad absorption spectra allowing visualization with single light source,ii)exceptional photo-stability allowing long term studies and iii)narrow and symmetrical emission spectrum that is controlled by their size and material composition.These unique properties allow simultaneous excitation of different size of quantum dots with a single excitation light source,their simultaneous resolution and visualization as different colors.At present there are only a few studies that have tested quantum dots in cellular imaging.We describe here the use of quantum dots in mortalin imaging of normal and cancer cells.Mortalin staining pattern with quantum dots in both normal and cancer cells mimicked those obtained with organic florescence probes and were considerably stable.
基金supported by the Natural Scientific Foundation of China (21825501)National Key Research and Development Program (2016YFA0202500 and 2016YFA0200102)+1 种基金Australian Research Council (DP160103107, FT170100224)Tsinghua University Initiative Scientific Research Program。
文摘The demand for efficient and environmentally-benign electrocatalysts that help availably harness the renewable energy resources is growing rapidly. In recent years, increasing insights into the design of water electrolysers, fuel cells, and metal–air batteries emerge in response to the need for developing sustainable energy carriers, in which the oxygen evolution reaction and the oxygen reduction reaction play key roles. However, both reactions suffer from sluggish kinetics that restricts the reactivity. Therefore, it is vital to probe into the structure of the catalysts to exploit high-performance bifunctional oxygen electrocatalysts. Spinel-type catalysts are a class of materials with advantages of versatility, low toxicity, low expense, high abundance, flexible ion arrangement, and multivalence structure. In this review, we afford a basic overview of spinel-type materials and then introduce the relevant theoretical principles for electrocatalytic activity, following that we shed light on the structure–property relationship strategies for spinel-type catalysts including electronic structure, microstructure, phase and composition regulation,and coupling with electrically conductive supports. We elaborate the relationship between structure and property, in order to provide some insights into the design of spinel-type bifunctional oxygen electrocatalysts.
