Long-term climate changes related with urbanization in Tokyo, Japan, and recent temperature and heavy rainfall distribution in the Tokyo metropolitan area are reviewed. A relatively high temperature increase in annual...Long-term climate changes related with urbanization in Tokyo, Japan, and recent temperature and heavy rainfall distribution in the Tokyo metropolitan area are reviewed. A relatively high temperature increase in annual mean temperature at the rate of 3.0°C/century was detected in Tokyo for the period 1901–2015. Some observational evidence showed the existence of both thermal and mechanical effects of urbanization on recent heavy rainfall occurrences, and modeling studies also support precipitation enhancement. Urban influences were recognized in other climatological elements, such as number of fog days, relative humidity, and wind circulation.展开更多
The present study describes a river channel management method for restoring riverine environments degraded by sand mining in rivers.Specifically,three conditions that must be met for a restored river channel in the lo...The present study describes a river channel management method for restoring riverine environments degraded by sand mining in rivers.Specifically,three conditions that must be met for a restored river channel in the lower reach of the Kelani River in Sri Lanka were proposed:(1)flood discharge capacity of the channel for a given flood,(2)prevention of saltwater intrusion,and(3)creation of a diverse physical environment.The allowable mining volume satisfies the three conditions,while continuing to mine sand was discussed based on the sediment budget calculations in the target river reach.In this case,the amount of sediment stored in the target reach and its variation are determined by the amount of sediment supplied to the target reach,the amount of sediment discharged from the target reach to the sea,and the amount of sediment excavated.This means that the dynamic equilibrium channel of the target reach is determined by the amount of sediment supplied and the amount of sediment excavated.The amount of sand mined when the dynamic equilibrium channel meets the three conditions of the restored channel is a candidate for the allowable amount of sand mined.One of these,the most desirable one,is set as the allowable mining volume.As described above,we proposed a method to develop a restoring reach taking the sediment budget and associated hydraulic and hydro morphological conditions in the target reach into consideration.展开更多
This study aims to clarify the conceptual characteristics of artifact utilization in nursing practice instruction. Five selected articles were analyzed using the concept analysis method by Walker and Avant. The attrib...This study aims to clarify the conceptual characteristics of artifact utilization in nursing practice instruction. Five selected articles were analyzed using the concept analysis method by Walker and Avant. The attributes, antecedents, and consequences of the concept were extracted from the target literature. The analysis revealed two attributes (“connecting people to people” and “connecting people to objects”);two antecedents (“recognition of artifacts” and “selection of artifacts”);and two consequences (“designing a fulfilling learning environment” and “improving the quality of education”). The concept was defined as “promoting the utilization of artifacts by recognizing and selecting them, connecting people to people and people to objects, designing a fulfilling learning environment, and improving the quality of education”.展开更多
Multimodal ultrasonic vibration(UV)assisted micro-forming has been widely investigated for its advantages of further reducing forming loads and improving forming quality.However,the influence mechanism of different UV...Multimodal ultrasonic vibration(UV)assisted micro-forming has been widely investigated for its advantages of further reducing forming loads and improving forming quality.However,the influence mechanism of different UV modes on microstructure evolution and mechanical properties was still unclear.Mul-timodal UV assisted micro-compression tests on T2 copper with different grains and sample sizes were conducted in this study.The microstructure evolution for different UV modes was observed by EBSD.The results showed that the true stress reduction caused by UV was increased sequentially with tool ultrasonic vibration(TV),mold ultrasonic vibration(MV)and compound ultrasonic vibration(CV).The region of grain deformation was shifted along the direction of UV,and the MV promoted the uniform distribution of deformation stress.The grain refinement,fiber streamline density,grain deformation and rotation degree were further enhanced under CV,due to the synergistic effect of TV and MV.Additionally,a coupled theoretical model considering both acoustic softening effect and size effect was proposed for describing the mechanical properties.And a physical model of dislocation motion in different UV modes was developed for describing the microstructure evolution.The maximum error between the theoretical and experimental results was only 2.39%.This study provides a theoretical basis for the optimization of UV assisted micro-forming process.展开更多
Precise manipulation of the catalytic spin configuration and delineation of the relationship between spin related properties and oxidation pathways remain significant challenges in Fenton-like processes.Herein,encapsu...Precise manipulation of the catalytic spin configuration and delineation of the relationship between spin related properties and oxidation pathways remain significant challenges in Fenton-like processes.Herein,encapsulated cobalt nanoparticles and cobalt-nitrogen-doped carbon moieties,endowed with confinement effects and variations in shell curvature were constructed via straightforward pyrolysis strategies,inducing alterations in magnetic anisotropy,electronic energy levels and spin polarization.The enhanced spin polarization at cobalt sites leads to a reduction in crystal field splitting energy and an increase in electronic spin density.This phenomenon facilitated electron transfer from cobalt orbitals to pz orbitals of oxygen species within peroxymonosulfate molecules,thereby promoting the formation of high-valent cobalt species.The encapsulation effectively stabilized cobalt nanoparticles,mitigating their dissolution or deactivation during reactions,which in turn enhances stability and durability in continuous flow processes.The high-valent cobalt species within the shell exhibit increased exposure and generate localized high concentrations,thereby intensifying interactions with migrating pollutants and enabling efficient and selective oxidation of emerging compounds with elevated redox potentials.This work underscores the profound impact of confined encapsulation curvature and spin polarization characteristics of metal sites on catalytic oxidation pathways and performance,opening novel avenues for spin engineering in practical environmental catalysis.展开更多
BACKGROUND Pancreatic neuroendocrine microtumors(PNEMTs)are small(<5 mm),nonfunctioning,well-differentiated neuroendocrine neoplasms.Although they are rare,they are not invariably benign.PNEMTs are typically discov...BACKGROUND Pancreatic neuroendocrine microtumors(PNEMTs)are small(<5 mm),nonfunctioning,well-differentiated neuroendocrine neoplasms.Although they are rare,they are not invariably benign.PNEMTs are typically discovered incidentally during autopsy.However,data regarding the occurrence of PNEMTs in the elderly population,particularly those identified incidentally in cadaveric studies,remain limited.AIM To investigate the prevalence and histopathological characteristics of PNEMTs in elderly individuals by analyzing cadaveric pancreatic tissues.METHODS We conducted a retrospective analysis of 85 pancreatic specimens(age range:58-109 years)obtained from cadavers for anatomical education and research at the Department of Life Dentistry,Nippon Dental University.Paraffin sections of the pancreatic head,body,and tail were prepared for histological and immunohistochemical analysis.RESULTS Five cases with PNEMTs(5/85,5.9%;male,n=33;female,n=52;mean age:85.8±12.1 years)were identified.The tumors were solitary,well circumscribed,and located within the pancreatic parenchyma(body:n=4;tail:n=1),and all were<5 mm(range:0.54-2.20 mm)in size.All tumors showed strong chromogranin A and synaptophysin positivity,and were predominantly glucagon(GLU)-positive.Ki-67 immunostaining indicated minimal proliferative activity;therefore,these tumors were considered non-functioning,GLU-producing,well-differentiated grade 1 PNEMTs.CONCLUSION Small,predominantly low-grade,GLU-secreting PNEMTs were present in 5.9%of elderly individuals,highlighting the prevalence of subclinical PNEMTs and the need for careful follow-up.展开更多
A series of scaled-model shaking table tests and its simulation analyses using dynamic finite element method were performed to clarify the dynamic behaviors and the seismic stability of embedded corrugated steel culve...A series of scaled-model shaking table tests and its simulation analyses using dynamic finite element method were performed to clarify the dynamic behaviors and the seismic stability of embedded corrugated steel culverts due to strong earth-quakes like the 1995 Hyogoken-nanbu earthquake. The dynamic strains of the embedded culvert models and the seismic soil pressure acting on the models due to sinusoidal and random strong motions were investigated. This study verified that the cor-rugated culvert model was subjected to dynamic horizontal forces (lateral seismic soil pressure) from the surrounding ground, which caused the large bending strains on the structure; and that the structures do not exceed the allowable plastic deformation and do not collapse completely during strong earthquake like Hyogoken-nanbu earthquake. The results obtained are useful for design and construction of embedded long span corrugated steel culverts in seismic regions.展开更多
The controlled cooling technology following hot rolling process is a vital factor that affects the final micro- structure and mechanical properties of the hot-rolled transformation induced plasticity (TRIP) steels. ...The controlled cooling technology following hot rolling process is a vital factor that affects the final micro- structure and mechanical properties of the hot-rolled transformation induced plasticity (TRIP) steels. In the present study, low alloy C-Si-Mn TRIP steel was successfully fabricated by hot rolling process with a 4450 hot roiling mill. To maximize the volume fraction and stability of retained austenite of the steel, two different cooling methods (aircooling and ultra-fast cooling "AC-UFC" and ultrmfast cooling, air cooling and ultra-fast cooling "UFC-AC-UFC") were conducted. The effects of the cooling method on the microstructure of hot-rolled TRIP steel were investigated via optical microscope, transmission electron microscope and conversion electron Mossbauer spectroscope. The mechanical properties of the steel were also evaluated by conventional tensile test. The results indicated that ferrite and bainite in the microstructure were refined with the cooling method of UFC-AC-UFC. The morphology of retained austenite was also changed from small islands distributing in bainite district (obtained with AC-UFC) to granular shape locating at the triple junction of the ferrite grain boundaries (obtained with UFC-AC-UFC). As a result, the TRIP steel with a content of retained austenite of 11. 52%, total elongation of 32% and product of tensile strength and total elongation of 27 552 MPa·% was obtained.展开更多
BACKGROUND Tamarix chinensis Lour(TCL)is a shrub that usually grows in arid or semiarid desert areas and saline-alkali fields.It is a traditional Chinese herbal medicine with hepatoprotective,antioxidant,antibacterial...BACKGROUND Tamarix chinensis Lour(TCL)is a shrub that usually grows in arid or semiarid desert areas and saline-alkali fields.It is a traditional Chinese herbal medicine with hepatoprotective,antioxidant,antibacterial,and antitumor activities.AIM To investigate the possible protective effects of TCL against liver injury induced by chronic ethanol intake.METHODS C57BL/6J male mice were fed a Lieber-DeCarli lipid diet containing alcohol and received(by gavage)a water-alcohol extract(80%)of TCL(100 and 200 mg/kg BW)or distilled water for 4 wk.After euthanasia,liver tissues were observed histologically with hematoxylin and eosin staining and Oil red O staining,and the levels of alanine aminotransferase,aspartate transaminase,hepatic lipids,reactive oxygen species,malondialdehyde,and superoxide dismutase were measured.In addition,expression of the NOD-like receptor family,pyrin domain-containing 3(NLRP3)inflammasome and downstream proinflammatory cytokines were determined.RESULTS Compared with the ethanol group,mice in the TCL-treated group(200 mg/kg)had significantly lower serum levels of alanine aminotransferase(mean,34.1 IU/L vs 45.3 IU/L,P<0.01)and aspartate transaminase(mean,89.6 IU/L vs 115.7 IU/L,P<0.01),as well as marked reduction of hepatic tissue reactive oxygen species(decreased by 27.5%,P<0.01)and malondialdehyde(decreased by 76.6%,P<0.01)levels,with a significant increase of superoxide dismutase(Increased by 73.2%,P<0.01).Expression of the NLRP3 inflammasome and its downstream cytokines[interleukin(IL)-1β,tumor necrosis factor-α,and IL-6],and recruitment of natural killer T cells to the liver,were reduced in the TCLtreated incubation with a Lieber-DeCaril ethanol lipid diet group.CONCLUSION These findings suggest that a TCL extract(200 mg/kg)protects against chronic ethanol-induced liver injury,probably by inhibiting the NLRP3-caspase-1-IL-1βsignaling pathway and suppressing oxidative stress.展开更多
1. Introduction Tokyo, one of the largest cities in the world, is the capital of Japan, a heavily earthquake-prone country. The Japanese population and much of its functionality are highly concentrated in Tokyo. The e...1. Introduction Tokyo, one of the largest cities in the world, is the capital of Japan, a heavily earthquake-prone country. The Japanese population and much of its functionality are highly concentrated in Tokyo. The estimated damage to Tokyo as a result of future large earthquakes with a magnitude greater than the Japanese scale 7 is extremely high. The number of casualties could exceed 20 000 due to both the shaking itself and post-earthquake fires.展开更多
CO_(x)(x=1,2)and O_(2) chemistry play key roles in tackling global severe environmental challenges and energy issues.To date,the efficient selective electrocatalytic transformations of COx-carbon chemicals,and O_(2)-h...CO_(x)(x=1,2)and O_(2) chemistry play key roles in tackling global severe environmental challenges and energy issues.To date,the efficient selective electrocatalytic transformations of COx-carbon chemicals,and O_(2)-hydrogenated products are still huge challenges.Single-atom catalysts(SACs)as atomic-scale novel catalysts in which only isolated metal atoms are dispersed on supports shed new insights in overcome these obstacles in CO_(x) and O_(2) chemistry,including CO oxidation,CO_(2) reduction reaction(CO_(2)RR),oxygen reduction reaction(ORR),and oxygen evolution reaction(OER).In this review,the unique features and advanced synthesis strategies of SACs from a viewpoint of fundamental synthesis design are first highlighted to guide future strategy design for controllable SAC synthesis.Then,the to-date reported CO_(2)RR,CO oxidation,OER,and ORR mechanism are included and summarized.More importantly,the design principles and design strategies of improving the intrinsic activity,selectivity,and stability are extensively discussed and the engineering strategy is classified as neighbor coordination engineering,metal-atom engineering,and substrate engineering.Via the comprehensive review and summary of state-of-the-art SACs,the synthesis–structure–property–mechanism–design principle relation can be revealed to shed lights into the structural construction of SACs.Finally,we present an outlook on current challenges and future directions for SACs in CO_(x) and O_(2) chemistry.展开更多
(Imido)vanadium(V)-alkylidene complexes of type V(CHSiMe3)(NR)(OR?)(PMe3)2 [R = Ad, C6H5, 2,6-Me2C6H3, 2,6-Cl2C6H3;R?= 2,6-Me2C6H3, 2,6-i Pr2C6H3, 2,6-F2C6H3, C6F5, C6Cl5] exhibited from moderate to remarkable catalyt...(Imido)vanadium(V)-alkylidene complexes of type V(CHSiMe3)(NR)(OR?)(PMe3)2 [R = Ad, C6H5, 2,6-Me2C6H3, 2,6-Cl2C6H3;R?= 2,6-Me2C6H3, 2,6-i Pr2C6H3, 2,6-F2C6H3, C6F5, C6Cl5] exhibited from moderate to remarkable catalytic activities for ringopening metathesis polymerization(ROMP) of norbornene(NBE). The catalytic activities were affected by the ligand substituents, and V(CHSiMe3)(N-2,6-Cl2C6H3)(OC6X5)(PMe3)2(X = F, Cl) demonstrated the exceptionally high catalytic activities for ROMP of NBE.The complexes polymerized cycloheptene(CHPE) and cis-cyclooctene(COE), and ROMP of COE by the OC6 Cl5 analogue proceeded in a living manner even at 80℃, and the activity increased with increasing the temperature up to 120 ℃. Highly active catalysts for ROMP of cyclic olefins(NBE, cyclopentene, and CHPE) can be generated in situ by premixing isolated V(CHSiMe3)(NC6F5)(O-2,6-iPr2C6H3)(PMe3)2 with 1.0 equiv. of C6F5OH or C6Cl5OH via immediate phenoxy exchange;the activity was affected by the kind of phenol added [TOF in the ROMPs of NBE: 4.62 × 10^4 min^–1(upon addition of C6F5OH) versus 37.3 min^–1(none)].展开更多
A new FAGE setup has recently been built at the University of Lille,France.It permits the quantification of OH and HO 2 in the atmosphere with a detection limit of 3×10 5 molecules/(cm 3 ·min) for OH and 1...A new FAGE setup has recently been built at the University of Lille,France.It permits the quantification of OH and HO 2 in the atmosphere with a detection limit of 3×10 5 molecules/(cm 3 ·min) for OH and 1×10 6 molecules/(cm 3 ·min) for HO 2.Its coupling to a photolysis cell enables the measurement of the total reactivity of the hydroxyl radical in ambient air and kinetic studies in laboratory.Two configurations have been considered:one with the photolysis cell at 90° to the FAGE nozzle,the other on line with the FAGE nozzle.The two configurations have been tested and validated by measuring the well known rate constants of OH with CH 4,C 3 H 8 and CO.The advantages and drawbacks of each configuration have been evaluated.The "on line" configuration limits losses and permits measurements over a larger reactivity range but is affected by OH formation from the laser beam striking the FAGE nozzle,thus limiting the ability to carry out energy dependence studies which can,in contrast,be successfully performed in the 90° configuration.展开更多
A simply fabricated microfluidic device integrated with a fluorescence detection system has been developed for on-line determination of ammonium in aqueous samples. A 365-nm light-emitting diode (LED) as an excitati...A simply fabricated microfluidic device integrated with a fluorescence detection system has been developed for on-line determination of ammonium in aqueous samples. A 365-nm light-emitting diode (LED) as an excitation source and a minor band pass filter were mounted into a polydimethylsiloxane (PDMS)-based microchip for the purpose of miniaturization of the entire analytical system. The ammonium sample reacted with o-phthaldialdehyde (OPA) on-chip with sodium sulfite as reducing reagent to produce a fluorescent isoindole derivative, which can emit fluorescence signal at about 425 nm when excited at 365 nm. Effects of pH, flow rate of solutions, concentrations of OPA-reagent, phosphate and sulfite salt were investigated. The calibration curve of ammonium in the range of 0.018- 1.8 μg/mL showed a good linear relationship with R2 = 0.9985, and the detection limit was (S /N = 3) 3.6 × 10 4 μg/mL. The relative standard deviation was 2.8% (n = 11) by calculating at 0.18 μg/mL ammonium for repeated detection. The system was applied to determine the ammonium concentration in rain and river waters, even extent to other analytes fluorescence detection by the presented device.展开更多
Basic research on pluripotent stem cells is designed to enhance understanding of embryogenesis, whereas applied research is designed to develop novel therapies and prevent diseases. Attainment of these goals has been ...Basic research on pluripotent stem cells is designed to enhance understanding of embryogenesis, whereas applied research is designed to develop novel therapies and prevent diseases. Attainment of these goals has been enhanced by the establishment of embryonic stem cell lines, the technological development of genomic reprogramming to generate induced-pluripotent stem cells, and improvements in in vitro techniques to manipulate stem cells. This review summarizes the techniques required to generate neural cells from pluripotent stem cells. In particular, this review describes current research applications of a simple neural differentiation method, the neural stem sphere method, which we developed.展开更多
Superoxide dismutase (SOD) and ascorbate peroxidase (APX) play central roles in the pathway for scavenging reactive oxygen species in plants, thereby contributing to the tolerance against abiotic stress. Here we repor...Superoxide dismutase (SOD) and ascorbate peroxidase (APX) play central roles in the pathway for scavenging reactive oxygen species in plants, thereby contributing to the tolerance against abiotic stress. Here we report the responses of cytosolic SOD (cSOD; sodCc1 and sodCc2) and cytosolic APX (cAPX; OsAPX1 and OsAPX2) genes to oxidative and abiotic stress in rice. RNA blot analyses revealed that methyl viologen treatment caused a more prominent induction of cAPXs compared with cSODs, and hydrogen peroxide treatment induced the expression of cAPXs whereas cSODs were not affected. These results suggest that cAPXs play more important roles in defense against oxidative stress compared with cSODs. It is noted that cSODs and cAPXs showed coordinate response to abscisic acid treatment which induced both sodCc1 and OsAPX2. However, cSODs and cAPXs responded differentially to drought, salt and chilling stress, which indicates that cSOD and cAPX genes are expressed differentially in response to oxidative and abiotic stress in rice.展开更多
A composting toilet using sawdust as a matrix has the potential to trap pathogens that might occasionally be contained in human feces. Therefore, care should be taken when handling the sawdust. It should also be noted...A composting toilet using sawdust as a matrix has the potential to trap pathogens that might occasionally be contained in human feces. Therefore, care should be taken when handling the sawdust. It should also be noted that pathogenic viruses tend to have stronger tolerance than pathogenic bacteria. The fates of several species of coliphages, T4, λ, Qβ and MS2, in sawdust were investigated as a viral model. The fates of coliphages were significantly different among them, and they changed in response to temperature and the water content of the sawdust. As the results, T4 coliphage had the strongest tolerance and Qβ had the weakest one in sawdust. It was estimated the days required to decrease virus to a safe level based on a risk assessment. According to the rates of Qβ and T4, 15 days and 167 days were required respectively for a safe level of infection risk based on actually operated composting toilet condition. Thus, it was significantly different depending on the species and sawdust conditions.展开更多
The effect of fluidity on open cell AZ31 metal foam samples fabricated using a solid state space holder method was investigated.Granule was fabricated by plaster powder and perlite powder.Granules were sieved which co...The effect of fluidity on open cell AZ31 metal foam samples fabricated using a solid state space holder method was investigated.Granule was fabricated by plaster powder and perlite powder.Granules were sieved which compacted layer by layer in casting mold.Preforms which made by granules were then heated to 200℃,300℃,400℃,500℃ under a rough(mechanical)vacuum before pressure infiltration with AZ31 Mg alloy.Samples were infiltrated using vacuum pressure values range of 8-14 KPa.The conditions of pressure and temperature were performed in order to get different fluidity on manufacturer of open cell AZ31 metal foam specimen quantity.It is found that the fluidity plays significant role to determine the open cell AZ31 alloy foam.The fluidity is affected by preheat temperature and infiltration vacuum pressure.The macrostructure,the distribution of the pores,microstructure,infiltration length,and porosity were investigated.展开更多
This study aimed to produce a prototype system for non-contact vital sign monitoring of the elderly using microwave radar with the intention of reducing the burdens on monitored individuals and nursing caregivers. In ...This study aimed to produce a prototype system for non-contact vital sign monitoring of the elderly using microwave radar with the intention of reducing the burdens on monitored individuals and nursing caregivers. In addition, we tested the ability of the proposed prototype system to measure the respiratory and heart rates of the elderly in a nursing home and discussed the systems effectiveness and problems by examining results of real-time monitoring. The prototype system consisted of two 24-GHz microwave radar antennas and an analysis system. The antennas were positioned below a mattress to monitor motion on the body surface for measuring cardiac and respiratory rates from the dorsal side of the subjects (23.3 ± 1.2 years) who would be lying on the mattress. The heart rates determined by the prototype system correlated significantly with those measured by electrocardiography (r = 0.92). Similarly, the respiratory rates determined by the prototype correlated with those obtained from respiration curves (r = 0.94). Next, we investigated the effectiveness of the prototype system with 7 elderly patients (93.3 ± 10.56 years) at a nursing home. The proposed system appears to be a promising tool for monitoring the vital signs of the elderly in a way that alleviates the need to attach electrodes overnight to confirm patient safety.展开更多
基金supported by the KAKENHI Grant (No. 26220202) from the Japan Society for the Promotion of Science (JSPS)the Leading Project in Japanese Fiscal Year 2015 and 2016 of Tokyo Metropolitan University
文摘Long-term climate changes related with urbanization in Tokyo, Japan, and recent temperature and heavy rainfall distribution in the Tokyo metropolitan area are reviewed. A relatively high temperature increase in annual mean temperature at the rate of 3.0°C/century was detected in Tokyo for the period 1901–2015. Some observational evidence showed the existence of both thermal and mechanical effects of urbanization on recent heavy rainfall occurrences, and modeling studies also support precipitation enhancement. Urban influences were recognized in other climatological elements, such as number of fog days, relative humidity, and wind circulation.
基金Tokyo Metropolitan Government,Grant/Award Number:Advanced Research Grant Number(R4-2)。
文摘The present study describes a river channel management method for restoring riverine environments degraded by sand mining in rivers.Specifically,three conditions that must be met for a restored river channel in the lower reach of the Kelani River in Sri Lanka were proposed:(1)flood discharge capacity of the channel for a given flood,(2)prevention of saltwater intrusion,and(3)creation of a diverse physical environment.The allowable mining volume satisfies the three conditions,while continuing to mine sand was discussed based on the sediment budget calculations in the target river reach.In this case,the amount of sediment stored in the target reach and its variation are determined by the amount of sediment supplied to the target reach,the amount of sediment discharged from the target reach to the sea,and the amount of sediment excavated.This means that the dynamic equilibrium channel of the target reach is determined by the amount of sediment supplied and the amount of sediment excavated.The amount of sand mined when the dynamic equilibrium channel meets the three conditions of the restored channel is a candidate for the allowable amount of sand mined.One of these,the most desirable one,is set as the allowable mining volume.As described above,we proposed a method to develop a restoring reach taking the sediment budget and associated hydraulic and hydro morphological conditions in the target reach into consideration.
文摘This study aims to clarify the conceptual characteristics of artifact utilization in nursing practice instruction. Five selected articles were analyzed using the concept analysis method by Walker and Avant. The attributes, antecedents, and consequences of the concept were extracted from the target literature. The analysis revealed two attributes (“connecting people to people” and “connecting people to objects”);two antecedents (“recognition of artifacts” and “selection of artifacts”);and two consequences (“designing a fulfilling learning environment” and “improving the quality of education”). The concept was defined as “promoting the utilization of artifacts by recognizing and selecting them, connecting people to people and people to objects, designing a fulfilling learning environment, and improving the quality of education”.
基金supported by the National Key Research and Development Program(No.2022YFB4602502)the Guangdong Basic and Applied Basic Research Foundation(No.2021A1515011991)+2 种基金the Key Research and Development Program Fund of Hubei Province(No.2022BAA057)the state Key Lab-oratory of Solidification Processing in NPU(No.SKLSP202325)the China Scholarship Council Visiting PhD Program(No.202306410136).
文摘Multimodal ultrasonic vibration(UV)assisted micro-forming has been widely investigated for its advantages of further reducing forming loads and improving forming quality.However,the influence mechanism of different UV modes on microstructure evolution and mechanical properties was still unclear.Mul-timodal UV assisted micro-compression tests on T2 copper with different grains and sample sizes were conducted in this study.The microstructure evolution for different UV modes was observed by EBSD.The results showed that the true stress reduction caused by UV was increased sequentially with tool ultrasonic vibration(TV),mold ultrasonic vibration(MV)and compound ultrasonic vibration(CV).The region of grain deformation was shifted along the direction of UV,and the MV promoted the uniform distribution of deformation stress.The grain refinement,fiber streamline density,grain deformation and rotation degree were further enhanced under CV,due to the synergistic effect of TV and MV.Additionally,a coupled theoretical model considering both acoustic softening effect and size effect was proposed for describing the mechanical properties.And a physical model of dislocation motion in different UV modes was developed for describing the microstructure evolution.The maximum error between the theoretical and experimental results was only 2.39%.This study provides a theoretical basis for the optimization of UV assisted micro-forming process.
文摘Precise manipulation of the catalytic spin configuration and delineation of the relationship between spin related properties and oxidation pathways remain significant challenges in Fenton-like processes.Herein,encapsulated cobalt nanoparticles and cobalt-nitrogen-doped carbon moieties,endowed with confinement effects and variations in shell curvature were constructed via straightforward pyrolysis strategies,inducing alterations in magnetic anisotropy,electronic energy levels and spin polarization.The enhanced spin polarization at cobalt sites leads to a reduction in crystal field splitting energy and an increase in electronic spin density.This phenomenon facilitated electron transfer from cobalt orbitals to pz orbitals of oxygen species within peroxymonosulfate molecules,thereby promoting the formation of high-valent cobalt species.The encapsulation effectively stabilized cobalt nanoparticles,mitigating their dissolution or deactivation during reactions,which in turn enhances stability and durability in continuous flow processes.The high-valent cobalt species within the shell exhibit increased exposure and generate localized high concentrations,thereby intensifying interactions with migrating pollutants and enabling efficient and selective oxidation of emerging compounds with elevated redox potentials.This work underscores the profound impact of confined encapsulation curvature and spin polarization characteristics of metal sites on catalytic oxidation pathways and performance,opening novel avenues for spin engineering in practical environmental catalysis.
基金Supported by Grant-in-Aid for Scientific Research from the Ministry of Education,Culture,Sports,Science and Technology of Japan,No.25K10147.
文摘BACKGROUND Pancreatic neuroendocrine microtumors(PNEMTs)are small(<5 mm),nonfunctioning,well-differentiated neuroendocrine neoplasms.Although they are rare,they are not invariably benign.PNEMTs are typically discovered incidentally during autopsy.However,data regarding the occurrence of PNEMTs in the elderly population,particularly those identified incidentally in cadaveric studies,remain limited.AIM To investigate the prevalence and histopathological characteristics of PNEMTs in elderly individuals by analyzing cadaveric pancreatic tissues.METHODS We conducted a retrospective analysis of 85 pancreatic specimens(age range:58-109 years)obtained from cadavers for anatomical education and research at the Department of Life Dentistry,Nippon Dental University.Paraffin sections of the pancreatic head,body,and tail were prepared for histological and immunohistochemical analysis.RESULTS Five cases with PNEMTs(5/85,5.9%;male,n=33;female,n=52;mean age:85.8±12.1 years)were identified.The tumors were solitary,well circumscribed,and located within the pancreatic parenchyma(body:n=4;tail:n=1),and all were<5 mm(range:0.54-2.20 mm)in size.All tumors showed strong chromogranin A and synaptophysin positivity,and were predominantly glucagon(GLU)-positive.Ki-67 immunostaining indicated minimal proliferative activity;therefore,these tumors were considered non-functioning,GLU-producing,well-differentiated grade 1 PNEMTs.CONCLUSION Small,predominantly low-grade,GLU-secreting PNEMTs were present in 5.9%of elderly individuals,highlighting the prevalence of subclinical PNEMTs and the need for careful follow-up.
文摘A series of scaled-model shaking table tests and its simulation analyses using dynamic finite element method were performed to clarify the dynamic behaviors and the seismic stability of embedded corrugated steel culverts due to strong earth-quakes like the 1995 Hyogoken-nanbu earthquake. The dynamic strains of the embedded culvert models and the seismic soil pressure acting on the models due to sinusoidal and random strong motions were investigated. This study verified that the cor-rugated culvert model was subjected to dynamic horizontal forces (lateral seismic soil pressure) from the surrounding ground, which caused the large bending strains on the structure; and that the structures do not exceed the allowable plastic deformation and do not collapse completely during strong earthquake like Hyogoken-nanbu earthquake. The results obtained are useful for design and construction of embedded long span corrugated steel culverts in seismic regions.
基金Key Projects in National Science and Technology Pillar Program During the Eleventh Five-Year Plan Period of China(2006BAE03A08)
文摘The controlled cooling technology following hot rolling process is a vital factor that affects the final micro- structure and mechanical properties of the hot-rolled transformation induced plasticity (TRIP) steels. In the present study, low alloy C-Si-Mn TRIP steel was successfully fabricated by hot rolling process with a 4450 hot roiling mill. To maximize the volume fraction and stability of retained austenite of the steel, two different cooling methods (aircooling and ultra-fast cooling "AC-UFC" and ultrmfast cooling, air cooling and ultra-fast cooling "UFC-AC-UFC") were conducted. The effects of the cooling method on the microstructure of hot-rolled TRIP steel were investigated via optical microscope, transmission electron microscope and conversion electron Mossbauer spectroscope. The mechanical properties of the steel were also evaluated by conventional tensile test. The results indicated that ferrite and bainite in the microstructure were refined with the cooling method of UFC-AC-UFC. The morphology of retained austenite was also changed from small islands distributing in bainite district (obtained with AC-UFC) to granular shape locating at the triple junction of the ferrite grain boundaries (obtained with UFC-AC-UFC). As a result, the TRIP steel with a content of retained austenite of 11. 52%, total elongation of 32% and product of tensile strength and total elongation of 27 552 MPa·% was obtained.
基金the Innovation Project of Shandong Academy of Medical Sciencethe Science and Technology Major Project of Shandong province,No.2015ZDJS03002.
文摘BACKGROUND Tamarix chinensis Lour(TCL)is a shrub that usually grows in arid or semiarid desert areas and saline-alkali fields.It is a traditional Chinese herbal medicine with hepatoprotective,antioxidant,antibacterial,and antitumor activities.AIM To investigate the possible protective effects of TCL against liver injury induced by chronic ethanol intake.METHODS C57BL/6J male mice were fed a Lieber-DeCarli lipid diet containing alcohol and received(by gavage)a water-alcohol extract(80%)of TCL(100 and 200 mg/kg BW)or distilled water for 4 wk.After euthanasia,liver tissues were observed histologically with hematoxylin and eosin staining and Oil red O staining,and the levels of alanine aminotransferase,aspartate transaminase,hepatic lipids,reactive oxygen species,malondialdehyde,and superoxide dismutase were measured.In addition,expression of the NOD-like receptor family,pyrin domain-containing 3(NLRP3)inflammasome and downstream proinflammatory cytokines were determined.RESULTS Compared with the ethanol group,mice in the TCL-treated group(200 mg/kg)had significantly lower serum levels of alanine aminotransferase(mean,34.1 IU/L vs 45.3 IU/L,P<0.01)and aspartate transaminase(mean,89.6 IU/L vs 115.7 IU/L,P<0.01),as well as marked reduction of hepatic tissue reactive oxygen species(decreased by 27.5%,P<0.01)and malondialdehyde(decreased by 76.6%,P<0.01)levels,with a significant increase of superoxide dismutase(Increased by 73.2%,P<0.01).Expression of the NLRP3 inflammasome and its downstream cytokines[interleukin(IL)-1β,tumor necrosis factor-α,and IL-6],and recruitment of natural killer T cells to the liver,were reduced in the TCLtreated incubation with a Lieber-DeCaril ethanol lipid diet group.CONCLUSION These findings suggest that a TCL extract(200 mg/kg)protects against chronic ethanol-induced liver injury,probably by inhibiting the NLRP3-caspase-1-IL-1βsignaling pathway and suppressing oxidative stress.
文摘1. Introduction Tokyo, one of the largest cities in the world, is the capital of Japan, a heavily earthquake-prone country. The Japanese population and much of its functionality are highly concentrated in Tokyo. The estimated damage to Tokyo as a result of future large earthquakes with a magnitude greater than the Japanese scale 7 is extremely high. The number of casualties could exceed 20 000 due to both the shaking itself and post-earthquake fires.
基金supported by the National Natural Science Foundation of China(No.51632007)the National Science and Technology Major Project(2017-VI-0007-0077)。
文摘CO_(x)(x=1,2)and O_(2) chemistry play key roles in tackling global severe environmental challenges and energy issues.To date,the efficient selective electrocatalytic transformations of COx-carbon chemicals,and O_(2)-hydrogenated products are still huge challenges.Single-atom catalysts(SACs)as atomic-scale novel catalysts in which only isolated metal atoms are dispersed on supports shed new insights in overcome these obstacles in CO_(x) and O_(2) chemistry,including CO oxidation,CO_(2) reduction reaction(CO_(2)RR),oxygen reduction reaction(ORR),and oxygen evolution reaction(OER).In this review,the unique features and advanced synthesis strategies of SACs from a viewpoint of fundamental synthesis design are first highlighted to guide future strategy design for controllable SAC synthesis.Then,the to-date reported CO_(2)RR,CO oxidation,OER,and ORR mechanism are included and summarized.More importantly,the design principles and design strategies of improving the intrinsic activity,selectivity,and stability are extensively discussed and the engineering strategy is classified as neighbor coordination engineering,metal-atom engineering,and substrate engineering.Via the comprehensive review and summary of state-of-the-art SACs,the synthesis–structure–property–mechanism–design principle relation can be revealed to shed lights into the structural construction of SACs.Finally,we present an outlook on current challenges and future directions for SACs in CO_(x) and O_(2) chemistry.
基金partly supported by Grant-in-Aid for Scientific Research on Innovative Areas ("3D Active-Site Science", No. 26105003) from The Ministry of Education, Culture, Sports, Science and Technology (MEXT), JapanGrant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (JSPS, Nos. 15H03812, 18H01982)the Tokyo Metropolitan government (Tokyo Human Resources Fund for City Diplomacy) for pre-doctoral fellowship
文摘(Imido)vanadium(V)-alkylidene complexes of type V(CHSiMe3)(NR)(OR?)(PMe3)2 [R = Ad, C6H5, 2,6-Me2C6H3, 2,6-Cl2C6H3;R?= 2,6-Me2C6H3, 2,6-i Pr2C6H3, 2,6-F2C6H3, C6F5, C6Cl5] exhibited from moderate to remarkable catalytic activities for ringopening metathesis polymerization(ROMP) of norbornene(NBE). The catalytic activities were affected by the ligand substituents, and V(CHSiMe3)(N-2,6-Cl2C6H3)(OC6X5)(PMe3)2(X = F, Cl) demonstrated the exceptionally high catalytic activities for ROMP of NBE.The complexes polymerized cycloheptene(CHPE) and cis-cyclooctene(COE), and ROMP of COE by the OC6 Cl5 analogue proceeded in a living manner even at 80℃, and the activity increased with increasing the temperature up to 120 ℃. Highly active catalysts for ROMP of cyclic olefins(NBE, cyclopentene, and CHPE) can be generated in situ by premixing isolated V(CHSiMe3)(NC6F5)(O-2,6-iPr2C6H3)(PMe3)2 with 1.0 equiv. of C6F5OH or C6Cl5OH via immediate phenoxy exchange;the activity was affected by the kind of phenol added [TOF in the ROMPs of NBE: 4.62 × 10^4 min^–1(upon addition of C6F5OH) versus 37.3 min^–1(none)].
基金supported by the Nord-Pas de Calais region in the frame of the IRENI research program,by the French Research Ministry,by the European Fund for Regional Economic Development (FEDER)the EU for financial support through project MEST-CT-2005-020659the French Government for financial aid through an EIFFEL scholarship
文摘A new FAGE setup has recently been built at the University of Lille,France.It permits the quantification of OH and HO 2 in the atmosphere with a detection limit of 3×10 5 molecules/(cm 3 ·min) for OH and 1×10 6 molecules/(cm 3 ·min) for HO 2.Its coupling to a photolysis cell enables the measurement of the total reactivity of the hydroxyl radical in ambient air and kinetic studies in laboratory.Two configurations have been considered:one with the photolysis cell at 90° to the FAGE nozzle,the other on line with the FAGE nozzle.The two configurations have been tested and validated by measuring the well known rate constants of OH with CH 4,C 3 H 8 and CO.The advantages and drawbacks of each configuration have been evaluated.The "on line" configuration limits losses and permits measurements over a larger reactivity range but is affected by OH formation from the laser beam striking the FAGE nozzle,thus limiting the ability to carry out energy dependence studies which can,in contrast,be successfully performed in the 90° configuration.
基金supported by the National Natural Science Foundation of China (No. 90813015, 30772006)the National Basic Research Program (973) of China (No.2007CB714507)
文摘A simply fabricated microfluidic device integrated with a fluorescence detection system has been developed for on-line determination of ammonium in aqueous samples. A 365-nm light-emitting diode (LED) as an excitation source and a minor band pass filter were mounted into a polydimethylsiloxane (PDMS)-based microchip for the purpose of miniaturization of the entire analytical system. The ammonium sample reacted with o-phthaldialdehyde (OPA) on-chip with sodium sulfite as reducing reagent to produce a fluorescent isoindole derivative, which can emit fluorescence signal at about 425 nm when excited at 365 nm. Effects of pH, flow rate of solutions, concentrations of OPA-reagent, phosphate and sulfite salt were investigated. The calibration curve of ammonium in the range of 0.018- 1.8 μg/mL showed a good linear relationship with R2 = 0.9985, and the detection limit was (S /N = 3) 3.6 × 10 4 μg/mL. The relative standard deviation was 2.8% (n = 11) by calculating at 0.18 μg/mL ammonium for repeated detection. The system was applied to determine the ammonium concentration in rain and river waters, even extent to other analytes fluorescence detection by the presented device.
基金Supported by Grant-in-Aid for Young Scientists(B),No.24791230Research Grant for long-range research initiative from JCIA+1 种基金Selective Research Fund of Tokyo Metropolitan Universitya Grant-in-Aid for Scientific Research,No.20500339
文摘Basic research on pluripotent stem cells is designed to enhance understanding of embryogenesis, whereas applied research is designed to develop novel therapies and prevent diseases. Attainment of these goals has been enhanced by the establishment of embryonic stem cell lines, the technological development of genomic reprogramming to generate induced-pluripotent stem cells, and improvements in in vitro techniques to manipulate stem cells. This review summarizes the techniques required to generate neural cells from pluripotent stem cells. In particular, this review describes current research applications of a simple neural differentiation method, the neural stem sphere method, which we developed.
基金supported by the Grants-in-Aid for Scientific Research (Grant No. 10460149 to K.T. and Grant No. 11740448 to S.M.) from the Ministry of Education, Culture, Sports, Science and Technology of Japana grant from the Rice Genome Research Program (Grant No. MP2106 to K.T.) from the Ministry of Agriculture, Forestry and Fisheries of Japan
文摘Superoxide dismutase (SOD) and ascorbate peroxidase (APX) play central roles in the pathway for scavenging reactive oxygen species in plants, thereby contributing to the tolerance against abiotic stress. Here we report the responses of cytosolic SOD (cSOD; sodCc1 and sodCc2) and cytosolic APX (cAPX; OsAPX1 and OsAPX2) genes to oxidative and abiotic stress in rice. RNA blot analyses revealed that methyl viologen treatment caused a more prominent induction of cAPXs compared with cSODs, and hydrogen peroxide treatment induced the expression of cAPXs whereas cSODs were not affected. These results suggest that cAPXs play more important roles in defense against oxidative stress compared with cSODs. It is noted that cSODs and cAPXs showed coordinate response to abscisic acid treatment which induced both sodCc1 and OsAPX2. However, cSODs and cAPXs responded differentially to drought, salt and chilling stress, which indicates that cSOD and cAPX genes are expressed differentially in response to oxidative and abiotic stress in rice.
基金supported by Grants-in-Aid for Scientific Research (S) project of JSPS (Japan Society for the Promotion of Science)
文摘A composting toilet using sawdust as a matrix has the potential to trap pathogens that might occasionally be contained in human feces. Therefore, care should be taken when handling the sawdust. It should also be noted that pathogenic viruses tend to have stronger tolerance than pathogenic bacteria. The fates of several species of coliphages, T4, λ, Qβ and MS2, in sawdust were investigated as a viral model. The fates of coliphages were significantly different among them, and they changed in response to temperature and the water content of the sawdust. As the results, T4 coliphage had the strongest tolerance and Qβ had the weakest one in sawdust. It was estimated the days required to decrease virus to a safe level based on a risk assessment. According to the rates of Qβ and T4, 15 days and 167 days were required respectively for a safe level of infection risk based on actually operated composting toilet condition. Thus, it was significantly different depending on the species and sawdust conditions.
文摘The effect of fluidity on open cell AZ31 metal foam samples fabricated using a solid state space holder method was investigated.Granule was fabricated by plaster powder and perlite powder.Granules were sieved which compacted layer by layer in casting mold.Preforms which made by granules were then heated to 200℃,300℃,400℃,500℃ under a rough(mechanical)vacuum before pressure infiltration with AZ31 Mg alloy.Samples were infiltrated using vacuum pressure values range of 8-14 KPa.The conditions of pressure and temperature were performed in order to get different fluidity on manufacturer of open cell AZ31 metal foam specimen quantity.It is found that the fluidity plays significant role to determine the open cell AZ31 alloy foam.The fluidity is affected by preheat temperature and infiltration vacuum pressure.The macrostructure,the distribution of the pores,microstructure,infiltration length,and porosity were investigated.
文摘This study aimed to produce a prototype system for non-contact vital sign monitoring of the elderly using microwave radar with the intention of reducing the burdens on monitored individuals and nursing caregivers. In addition, we tested the ability of the proposed prototype system to measure the respiratory and heart rates of the elderly in a nursing home and discussed the systems effectiveness and problems by examining results of real-time monitoring. The prototype system consisted of two 24-GHz microwave radar antennas and an analysis system. The antennas were positioned below a mattress to monitor motion on the body surface for measuring cardiac and respiratory rates from the dorsal side of the subjects (23.3 ± 1.2 years) who would be lying on the mattress. The heart rates determined by the prototype system correlated significantly with those measured by electrocardiography (r = 0.92). Similarly, the respiratory rates determined by the prototype correlated with those obtained from respiration curves (r = 0.94). Next, we investigated the effectiveness of the prototype system with 7 elderly patients (93.3 ± 10.56 years) at a nursing home. The proposed system appears to be a promising tool for monitoring the vital signs of the elderly in a way that alleviates the need to attach electrodes overnight to confirm patient safety.