BACKGROUND Among patients with cirrhosis and pre-malignant or early malignant mucosal lesions,surgical intervention carries a much higher bleeding risk.When such lesions are discovered,endoscopic submucosal dissection...BACKGROUND Among patients with cirrhosis and pre-malignant or early malignant mucosal lesions,surgical intervention carries a much higher bleeding risk.When such lesions are discovered,endoscopic submucosal dissection(ESD)may offer curative therapy with lower risks than surgery and improved outcomes compared to traditional endoscopic resection.AIM To evaluate the outcomes of ESD in patients with cirrhosis.METHODS Patients with cirrhosis undergoing ESD between July 2015 and August 2022 were retrospectively matched in 1:2 fashion to controls based on lesion location,size,and anticoagulation use.Procedural outcomes were compared between groups.RESULTS A total of 64 Lesions from 59 patients were included(16 cirrhosis,43 control).There were no differences in patient or lesion characteristics between groups.En bloc and curative resection was achieved in 84.21%,78.94%of the cirrhosis group and 88.89%,68.89%of controls,respectively,with no significant differences.Cirrhotic patients had significantly higher rates of intra-procedural coagulation grasper use for control of bleeding(47.37%vs 20%;P=0.02).There were otherwise no significant differences in adverse event rates.In the 29 patients with follow up,we found higher rates of recurrence in the cirrhosis group compared to controls(40%vs 5.26%;P=0.019),however this effect did not persist on multivariable analysis controlling for known confounders.CONCLUSION ESD may be safe and effective in patients with cirrhosis.Most procedure related outcomes were not significantly different between groups.Intra-procedural bleeding requiring use of the coagulation grasper use was expectedly higher in the cirrhosis group given the known effects of liver disease on hemostasis.展开更多
Background:In vitro production of bovine embryos is a well-established technology,but the in vitro culture(IVC)system still warrants improvements,especially regarding embryo quality.This study aimed to evaluate the ef...Background:In vitro production of bovine embryos is a well-established technology,but the in vitro culture(IVC)system still warrants improvements,especially regarding embryo quality.This study aimed to evaluate the effect of extracellular vesicles(EVs)isolated from oviductal(OF)and uterine fluid(UF)in sequential IVC on the development and quality of bovine embryos.Zygotes were cultured in SOF supplemented with either BSA or EVs-depleted fetal calf serum(dFCS)in the presence(BSA-EV and dFCS-EV)or absence of EVs from OF(D1 to D4)and UF(D5 to D8),mimicking in vivo conditions.EVs from oviducts(early luteal phase)and uterine horns(mid-luteal phase)from slaughtered heifers were isolated by size exclusion chromatography.Blastocyst rate was recorded on days 7-8 and their quality was assessed based on lipid contents,mitochondrial activity and total cell numbers,as well as survival rate after vitrification.Relative mRNA abundance for lipid metabolism-related transcripts and levels of phosphorylated hormonesensitive lipase(pHSL)proteins were also determined.Additionally,the expression levels of 383 miRNA in OF-and UF-EVs were assessed by qRT-PCR.Results:Blastocyst yield was lower(P<0.05)in BSA treatments compared with dFCS treatments.Survival rates after vitrification/warming were improved in dFCS-EVs(P<0.05).EVs increased(P<0.05)blastocysts total cell number in dFCS-EV and BSA-EV compared with respective controls(dFCS and BSA),while lipid content was decreased in dFCSEV(P<0.05)and mitochondrial activity did not change(P>0.05).Lipid metabolism transcripts were affected by EVs and showed interaction with type of protein source in medium(PPARGC1B,LDLR,CD36,FASN and PNPLA2,P<0.05).Levels of pHSL were lower in dFCS(P<0.05).Twenty miRNA were differentially expressed between OF-and UF-EVs and only bta-miR-148b was increased in OF-EVs(P<0.05).Conclusions:Mimicking physiological conditions using EVs from OF and UF in sequential IVC does not affect embryo development but improves blastocyst quality regarding survival rate after vitrification/warming,total cell number,lipid content,and relative changes in expression of lipid metabolism transcripts and lipase activation.Finally,EVs miRNA contents may contribute to the observed effects.展开更多
The influence of annealing cycles up to 650 °C on the specific conductivity and hardness(HV) of hot-rolled sheets of Al alloys containing up to 0.5% Zr(mass fraction) was studied.Using analytical calculations...The influence of annealing cycles up to 650 °C on the specific conductivity and hardness(HV) of hot-rolled sheets of Al alloys containing up to 0.5% Zr(mass fraction) was studied.Using analytical calculations of phase composition and experimental methods(scanning electron microscopy,transmission electron microscopy,electron microprobe analysis,etc),it is demonstrated that the conductivity depends on the content of Zr in the Al solid solution which is the minimum after holding at 450 °C for 3 h.On the other hand,the hardness of the alloy is mainly caused by the amount of nanoparticles of the L12(Al3Zr) phase that defines the retention of strain hardening.It is shown that the best combination of electrical conductivity and hardness values can be reached within an acceptable holding time at the temperature about 450 °C.展开更多
This paper summarizes the research on non-structural elements and building contents being conducted at University of Canterbury in New Zealand. Since the 2010-2011 series of Canterbury earthquakes, in which damage to ...This paper summarizes the research on non-structural elements and building contents being conducted at University of Canterbury in New Zealand. Since the 2010-2011 series of Canterbury earthquakes, in which damage to non-structural components and contents contributed heavily to downtime and overall financial loss, attention to seismic performance and design of non-structural components and contents in buildings has increased exponentially in NZ. This has resulted in an increased allocation of resources to research leading to development of more resilient non-structural systems in buildings that would incur substantially less damage and cause little downtime during earthquakes. In the last few years, NZ researchers have made important developments in understanding and improving the seismic performance of secondary building elements such as partitions, facades, ceilings and contents.展开更多
Cloud forest ecosystems of the Latin American tropics are highly threatened by changes in land-use such as expanding croplands and livestock pastures that promote shifts in the structure and composition of plant commu...Cloud forest ecosystems of the Latin American tropics are highly threatened by changes in land-use such as expanding croplands and livestock pastures that promote shifts in the structure and composition of plant communities in these forests.However,shade coffee plantations represent a forest management alternative that has been shown to maintain biodiversity in these ecosystems.In this study,we evaluated changes in the composition,diversity,and structure of Mexican cloud-forest woody species for three land use categories:cattle pastures,shade coffee plantations and advanced succession forests.For each category,fifteen 0.28-ha plots were established and the composition and diversity of vegetation was noted.Composition of species was analyzed using ordination methods,and alpha diversity was compared using Hill numbers.Seventy-seven woody species belonging to 40 families were recorded.Species richness and diversity was high in both the advanced successional forest and coffee plantations compared to cattle pastures.Vegetation composition and structure was similar between late succession forests and coffee plantations with both land uses also being more structurally complex than cattle pastures.Our results show how shade coffee cultivation is a land-use activity that maintains woody plant communities in a manner that aligns with biodiversity conservation.展开更多
BACKGROUND A previous study showed that irrigation with 100 mL saline reduced residual common bile duct(CBD)stones,which potentially cause recurrent stones after endoscopic retrograde cholangiopancreatography.AIM To d...BACKGROUND A previous study showed that irrigation with 100 mL saline reduced residual common bile duct(CBD)stones,which potentially cause recurrent stones after endoscopic retrograde cholangiopancreatography.AIM To determine whether saline irrigation can improve CBD clearance after lithotripsy.METHODS This prospective self-controlled study enrolled patients receiving mechanical lithotripsy for large(>1.2 cm)CBD stones.After occlusion cholangiography confirmed CBD stone clearance,peroral cholangioscopy(POC)was performed to determine clearance scores based on the number of residual stones.The amounts of residual stones spotted via POC were graded on a 5-point scale(score 1,worst;score 5,best).Scores were documented after only stone removal(control)and after irrigation with 50 mL and 100 mL saline,respectively.The stone composition was analyzed using infrared spectroscopy.RESULTS Between October 2018 and January 2020,47 patients had CBD clearance scores of 2.4±1.1 without saline irrigation,3.5±0.7 with 50 mL irrigation,and 4.6±0.6 with 100 mL irrigation(P<0.001).Multivariate analysis showed that CBD diameter>15 mm[odds ratio(OR)=0.08,95%confidence interval(CI):0.01-0.49;P=0.007]and periampullary diverticula(PAD)(OR=6.51,95%CI:1.08-39.21;P=0.041)were independent risk factors for residual stones.Bilirubin pigment stones constituted the main residual stones found in patients with PAD(P=0.004).CONCLUSION Irrigation with 100 mL of saline may not clear all residual CBD stones after lithotripsy,especially in patients with PAD and/or a dilated(>15 mm)CBD.Pigment residual stones are soft and commonly found in patients with PAD.Additional saline irrigation may be required to remove retained stones.展开更多
The challenge in the practical application of rocking foundations is the estimation of its performance,particularly the rotation angle,during a strong earthquake.In this study,the dynamic rocking behavior for a shallo...The challenge in the practical application of rocking foundations is the estimation of its performance,particularly the rotation angle,during a strong earthquake.In this study,the dynamic rocking behavior for a shallow foundation considering structural response was evaluated through two analytical approaches:the conventional soil-foundation-structure interaction(SFSI)governing equation of a single-degree-of-freedom(SDOF)structure on a rocking shallow foundation,and the Housner rocking model(i.e.,a rocking rigid block on a rigid base).Both approaches were validated with dynamic centrifuge tests.The test models consisted of a soft soil deposit,a shallow rectangular foundation,and an SDOF structure dominated by a bending behavior.A total of 11 foundation-structure systems and six seismic waves,including recorded earthquake signals and sinusoidal waves,were utilized.The results showed that the conventional SFSI equation well predicted the maximum rotation during strong earthquakes.However,this method was less accurate regarding the rotational phase information and maximum rotation of the foundation during weak earthquakes.On the other hand,although the modified Housner′s rocking model required five parameters relevant to a soil-foundation-structure system,it overestimated the maximum rotation of the foundation when compared with the results from dynamic centrifuge tests.展开更多
In order to test the reliability of γ-GT foci(γ-glutamyltranspeptidase positive hepatocyticfoci) as a preneoplastic marker in AFB-inducedhepatocarcinogenesis, this experiment was car-ried out for a long period after...In order to test the reliability of γ-GT foci(γ-glutamyltranspeptidase positive hepatocyticfoci) as a preneoplastic marker in AFB-inducedhepatocarcinogenesis, this experiment was car-ried out for a long period after a short-term invivo test model of AFB-induced hepatocarcino-展开更多
Metal-based core-shell nanostructures have garnered enduring interest due to their unique properties and functionalities.However,their growth and transformation mechanisms in liquid media remain largely unknown becaus...Metal-based core-shell nanostructures have garnered enduring interest due to their unique properties and functionalities.However,their growth and transformation mechanisms in liquid media remain largely unknown because they lack direct observation of the dynamic growth process with high spatial and temporal resolution.Developing the in situ liquid cell transmission electron microscopy(TEM)technique offers unprecedented real-time imaging and spectroscopy capabilities to directly track the evolution of structural and chemical transformation of metal-based core–shell nanostructures in liquid media under their working condition.Here,this review highlights recent progress in utilizing in situ liquid cell TEM characterization technique in investigating the dynamic evolution of material structure and morphology of metal-based core–shell nanostructures at the nano/atomic scale in real-time.A brief introduction of the development of liquid cells for in situ TEM is first given.Subsequently,recent advances in in situ liquid cell TEM for the fundamental study of growth mechanisms of metal based core–shell nanostructures are discussed.Finally,the challenge and future developments of metalbased core–shell nanostructures for in situ liquid cell TEM are proposed.Our review is anticipated to inspire ongoing interest in revealing unseen growth dynamics of core–shell nanostructures by in situ liquid cell TEM technique.展开更多
Ecotourism is a tourism modality intricately linked to the principles of sustainability,due to its natural offer component and environmental education.The objective of this research is to evaluate the perception of ec...Ecotourism is a tourism modality intricately linked to the principles of sustainability,due to its natural offer component and environmental education.The objective of this research is to evaluate the perception of ecotourists present on the coast of Yucatan.From a regional approach,the author selected twenty-five community-based ecotourism ventures(CBET)present in the area and analysed the perception of ecotourists through a questionnaire and its respective statistical analysis with non-parametric tests,and developed a general profile of the ecotourist applying a sociodemographic segmentation and based on a geographical segmentation the author compared the perceptions of two populations:national ecotourists and international ecotourists.The data reveal that the profile of the ecotourist on the coast of Yucatan is similar to that postulated in the literature.In terms of environmental perception the author found a significant difference in both populations,and believed that this difference is because the international market is more critical and demanding.In addition,areas of opportunity were documented in the CBETs in the way they carry out their environmental communication.The author concluded that ecotourism in the region is still an activity in consolidation and although it presents great achievements.It is still not possible to qualify it as a sustainable activity.We call for continuing deepening the studies of ecotourism demand and evaluation of perception,through comparative,longitudinal studies and with new variables that allow new test statistics,to contribute new elements to the ecotourism debate.展开更多
Hybrid simulation can be a cost effective approach for dynamic testing of structural components at full scale while capturing the system level response through interactions with a numerical model.The dynamic response ...Hybrid simulation can be a cost effective approach for dynamic testing of structural components at full scale while capturing the system level response through interactions with a numerical model.The dynamic response of a seismically isolated structure depends on the combined characteristics of the ground motion,bearings,and superstructure.Therefore,dynamic full-scale system level tests of isolated structures under realistic dynamic loading conditions are desirable towards a holistic validation of this earthquake protection strategy.Moreover,bearing properties and their ultimate behavior have been shown to be highly dependent on rate-of-loading and scale size effects,especially under extreme loading conditions.Few laboratory facilities can test full-scale seismic isolation bearings under prescribed displacement and/or loading protocols.The adaptation of a full-scale bearing test machine for the implementation of real-time hybrid simulation is presented here with a focus on the challenges encountered in attaining reliable simulation results for large scale dynamic tests.These advanced real-time hybrid simulations of large and complex hybrid models with several thousands of degrees of freedom are some of the first to use high performance parallel computing to rapidly execute the numerical analyses.Challenges in the experimental setup included measured forces contaminated by delay and other systematic control errors in applying desired displacements.Friction and inertial forces generated by the large-scale loading apparatus can affect the accuracy of measured force feedbacks.Reliable results from real-time hybrid simulation requires implementation of compensation algorithms and correction of these various sources of errors.Overall,this research program confirms that real-time hybrid simulation is a viable testing method to experimentally assess the behavior of full-scale isolators while capturing interactions with the numerical models of the superstructure to evaluate system level and in-structure response.展开更多
The OpenSees computational platform has allowed unprecedented opportunities for conducting seismic nonlinear soil-structure interaction simulations.On the geotechnical side,capabilities such as coupled solid-fluid for...The OpenSees computational platform has allowed unprecedented opportunities for conducting seismic nonlinear soil-structure interaction simulations.On the geotechnical side,capabilities such as coupled solid-fluid formulations and nonlinear incrementalplasticity approaches allow for representation of the involved dynamic/seismic responses.This paper presents recent research that facilitated such endeavors in terms of response of ground-foundation-structure systems using advanced material modeling techniques and high-performance computing resources.Representative numerical results are shown for large-scale soil-structure systems,and ground modification liquefaction countermeasures.In addition,graphical user interface enabling tools for routine usage of such 3D simulation environments are presented,as an important element in support of wider adoption and practical applications.In this context,Performance-Based Earthquake Engineering(PBEE)analysis of bridge-ground systems is highlighted as an important topical application.展开更多
Ni-rich layered oxides are considered promising cathodes for advanced lithium-ion batteries(LIBs)in the future,owing to their high capacity and low cost.However,the issues on structural and interfacial stability of Ni...Ni-rich layered oxides are considered promising cathodes for advanced lithium-ion batteries(LIBs)in the future,owing to their high capacity and low cost.However,the issues on structural and interfacial stability of Ni-rich cathodes still pose substantial obstacles in the practical application of advanced LIBs.Here,we employ a one-step method to synthesize a B-doped and La_(4)NiLiO_(8)-coated LiNi_(0.82)5Co_(0.115)Mn_(0.06)O_(2)(BL-1)cathode with reliable structure and interface,for the first time.The La_(4)NiLiO_(8)coating layer can prevent cathodes from electrolyte assault and facilitate Li+diffusion kinetics.Moreover,B-doping can effectively restrain the pernicious H_(2)-H_(3) phase transition and adjust the orientation of primary particles to a radial alignment,which is obstructive to the arise of microcracks induced by the change of anisotropic volume.Specifically,when tested in pouch cells,the BL-1 cathode exhibits outstanding capacity retention of 93.49%after 500 cycles at 1 C.This dual-modification strategy dramatically enhances the stability of the structure and interface for Ni-rich cathode materials,consequently accelerating the commercialization process of high-energy–density LIBs.展开更多
BACKGROUND Metoclopramide may be used to treat people suffering from acute migraine.However,no comprehensive investigation on this issue has been recorded.This review will provide more solid evidence for the use of me...BACKGROUND Metoclopramide may be used to treat people suffering from acute migraine.However,no comprehensive investigation on this issue has been recorded.This review will provide more solid evidence for the use of metoclopramide in treating acute migraine.AIM To compare the efficacy of intravenous metoclopramide with other therapies in migraine attack treatment in an emergency department(ED).METHODS We included randomized controlled trials of participants older than 18 years with acute migraine headaches,which included at least one arm that received intravenous(IV)metoclopramide at the ED.A literature search of PubMed,Web of Science,Cochrane Collaboration,and Reference Citation Analysis on December 31,2021 retrieved other drugs or placebo-controlled studies without language limitation.The risk of bias was assessed using the Cochrane risk of bias tool.The primary endpoint was pain reduction at 60 min or closest to 1 h after treatment,as measured by the pain scale.Secondary endpoints included adverse effects or reactions resulting from metoclopramide or comparisons.RESULTS Fourteen trials with a total of 1661 individuals were eligible for review.The risk of bias ranged from low to intermediate.IV metoclopramide administration was not associated with higher pain reduction at 1 h(Standard mean difference[SMD]=-0.03,95%confidence interval[CI]:-0.33-0.28,P=0.87).However,metoclopramide was associated with better pain reduction than placebo(SMD=1.04,95%CI:0.50-1.58,P=0.0002).In addition,side effects were not significantly different between IV metoclopramide and other drugs or placebo(odds ratio[OR]=0.76,95%CI:0.48-1.19,P=0.09 and OR=0.92,95%CI:0.31-2.74,P=0.54,respectively).CONCLUSION Metoclopramide is more effective than placebo in treating migraine in the ED.Despite the observed tendency of decreased side effects,its effectiveness compared to other regimens is poorly understood.More research on this area is needed to treat migraine in acute care settings effectively.展开更多
High-temperature superconductivity in ceramic oxides is a new technology in which advances are occurring at a rapid pace. Here, the author describes some properties of a new nano crystalline ceramic Type II supercondu...High-temperature superconductivity in ceramic oxides is a new technology in which advances are occurring at a rapid pace. Here, the author describes some properties of a new nano crystalline ceramic Type II superconductor, PbSrCaCuO. Type II superconductors are usually made of metal alloys or complex oxide ceramics. The PSCCO perovskite phase structure was prepared by the conventional solid state reaction technique. In order to show the viability of the proposed method, super-conducting powder was prepared in special furnace. The sample was analyzed by X-ray Diffraction (XRD), Particle size determination, SEM and EDX. The comparison of XRD results with JCPDS files confirmed the orthorhombic structure of the sample with a ≠ b ≠ c and α = β = γ = 90°. Scanning electron microscopy (SEM) studies revealed that its particle size is in the nanometer range. It also confirmed the calculated value of particle size from Debye Scherrer’s formula. EDX spectrum shows the elements of the sample. X-ray instrumental peak broadening analysis was used to evaluate the size and lattice strain by the Williamson-Hall Plot method.展开更多
SUMMARY In many statistical applications,composite variables are constructed to reduce the number of variables and improve the performances of statistical analyses of these variables,especially when some of the variab...SUMMARY In many statistical applications,composite variables are constructed to reduce the number of variables and improve the performances of statistical analyses of these variables,especially when some of the variables are highly correlated.Principal component analysis(PCA)and factor analysis(FA)are generally used for such purposes.If the variables are used as explanatory or independent variables in linear regression analysis,partial least squares(PLS)regression is a better alternative.Unlike PCA and FA,PLS creates composite variables by also taking into account the response,or dependent variable,so that they have higher correlations with the response than composites from their PCA and FA counterparts.In this report,we provide an introduction to this useful approach and illustrate it with data from a real study.展开更多
基金reviewed and approved by the Baylor College of Medicine Institutional Review Board.
文摘BACKGROUND Among patients with cirrhosis and pre-malignant or early malignant mucosal lesions,surgical intervention carries a much higher bleeding risk.When such lesions are discovered,endoscopic submucosal dissection(ESD)may offer curative therapy with lower risks than surgery and improved outcomes compared to traditional endoscopic resection.AIM To evaluate the outcomes of ESD in patients with cirrhosis.METHODS Patients with cirrhosis undergoing ESD between July 2015 and August 2022 were retrospectively matched in 1:2 fashion to controls based on lesion location,size,and anticoagulation use.Procedural outcomes were compared between groups.RESULTS A total of 64 Lesions from 59 patients were included(16 cirrhosis,43 control).There were no differences in patient or lesion characteristics between groups.En bloc and curative resection was achieved in 84.21%,78.94%of the cirrhosis group and 88.89%,68.89%of controls,respectively,with no significant differences.Cirrhotic patients had significantly higher rates of intra-procedural coagulation grasper use for control of bleeding(47.37%vs 20%;P=0.02).There were otherwise no significant differences in adverse event rates.In the 29 patients with follow up,we found higher rates of recurrence in the cirrhosis group compared to controls(40%vs 5.26%;P=0.019),however this effect did not persist on multivariable analysis controlling for known confounders.CONCLUSION ESD may be safe and effective in patients with cirrhosis.Most procedure related outcomes were not significantly different between groups.Intra-procedural bleeding requiring use of the coagulation grasper use was expectedly higher in the cirrhosis group given the known effects of liver disease on hemostasis.
基金supported by the Spanish Ministry of Science and Innovation (PID2019-111641RB-I00 to DR, and RTI2018-093548-B-I00 to AGA)Sáo Paulo Research Foundation,Brazil (FAPESP+4 种基金#2017/20339-3 and CNPqBrazil 304276/2018-9 to CLVL#2019/04981-2 to RM2014/22887-0 and 2015/21829-9 to JCDS)Minciencias-Colombia Postdoctoral Fellowship (848-2019) to KC-BSecretaria de Educación Superior,Ciencia y Tecnología e Innovación (SENESCYT-Ecuador) to YNC.
文摘Background:In vitro production of bovine embryos is a well-established technology,but the in vitro culture(IVC)system still warrants improvements,especially regarding embryo quality.This study aimed to evaluate the effect of extracellular vesicles(EVs)isolated from oviductal(OF)and uterine fluid(UF)in sequential IVC on the development and quality of bovine embryos.Zygotes were cultured in SOF supplemented with either BSA or EVs-depleted fetal calf serum(dFCS)in the presence(BSA-EV and dFCS-EV)or absence of EVs from OF(D1 to D4)and UF(D5 to D8),mimicking in vivo conditions.EVs from oviducts(early luteal phase)and uterine horns(mid-luteal phase)from slaughtered heifers were isolated by size exclusion chromatography.Blastocyst rate was recorded on days 7-8 and their quality was assessed based on lipid contents,mitochondrial activity and total cell numbers,as well as survival rate after vitrification.Relative mRNA abundance for lipid metabolism-related transcripts and levels of phosphorylated hormonesensitive lipase(pHSL)proteins were also determined.Additionally,the expression levels of 383 miRNA in OF-and UF-EVs were assessed by qRT-PCR.Results:Blastocyst yield was lower(P<0.05)in BSA treatments compared with dFCS treatments.Survival rates after vitrification/warming were improved in dFCS-EVs(P<0.05).EVs increased(P<0.05)blastocysts total cell number in dFCS-EV and BSA-EV compared with respective controls(dFCS and BSA),while lipid content was decreased in dFCSEV(P<0.05)and mitochondrial activity did not change(P>0.05).Lipid metabolism transcripts were affected by EVs and showed interaction with type of protein source in medium(PPARGC1B,LDLR,CD36,FASN and PNPLA2,P<0.05).Levels of pHSL were lower in dFCS(P<0.05).Twenty miRNA were differentially expressed between OF-and UF-EVs and only bta-miR-148b was increased in OF-EVs(P<0.05).Conclusions:Mimicking physiological conditions using EVs from OF and UF in sequential IVC does not affect embryo development but improves blastocyst quality regarding survival rate after vitrification/warming,total cell number,lipid content,and relative changes in expression of lipid metabolism transcripts and lipase activation.Finally,EVs miRNA contents may contribute to the observed effects.
基金Project(RMEF157814X0004)supported by the Ministry of Education and Science of the Russian Federation
文摘The influence of annealing cycles up to 650 °C on the specific conductivity and hardness(HV) of hot-rolled sheets of Al alloys containing up to 0.5% Zr(mass fraction) was studied.Using analytical calculations of phase composition and experimental methods(scanning electron microscopy,transmission electron microscopy,electron microprobe analysis,etc),it is demonstrated that the conductivity depends on the content of Zr in the Al solid solution which is the minimum after holding at 450 °C for 3 h.On the other hand,the hardness of the alloy is mainly caused by the amount of nanoparticles of the L12(Al3Zr) phase that defines the retention of strain hardening.It is shown that the best combination of electrical conductivity and hardness values can be reached within an acceptable holding time at the temperature about 450 °C.
基金co-funded by the University of Canterbury,Natural Hazards Platform (NHP)the Ministry of Business,Innovation and Employment (MBIE),New Zealand
文摘This paper summarizes the research on non-structural elements and building contents being conducted at University of Canterbury in New Zealand. Since the 2010-2011 series of Canterbury earthquakes, in which damage to non-structural components and contents contributed heavily to downtime and overall financial loss, attention to seismic performance and design of non-structural components and contents in buildings has increased exponentially in NZ. This has resulted in an increased allocation of resources to research leading to development of more resilient non-structural systems in buildings that would incur substantially less damage and cause little downtime during earthquakes. In the last few years, NZ researchers have made important developments in understanding and improving the seismic performance of secondary building elements such as partitions, facades, ceilings and contents.
基金supported by CONACYT[858464]and the American Bird Conservancy[1917D].
文摘Cloud forest ecosystems of the Latin American tropics are highly threatened by changes in land-use such as expanding croplands and livestock pastures that promote shifts in the structure and composition of plant communities in these forests.However,shade coffee plantations represent a forest management alternative that has been shown to maintain biodiversity in these ecosystems.In this study,we evaluated changes in the composition,diversity,and structure of Mexican cloud-forest woody species for three land use categories:cattle pastures,shade coffee plantations and advanced succession forests.For each category,fifteen 0.28-ha plots were established and the composition and diversity of vegetation was noted.Composition of species was analyzed using ordination methods,and alpha diversity was compared using Hill numbers.Seventy-seven woody species belonging to 40 families were recorded.Species richness and diversity was high in both the advanced successional forest and coffee plantations compared to cattle pastures.Vegetation composition and structure was similar between late succession forests and coffee plantations with both land uses also being more structurally complex than cattle pastures.Our results show how shade coffee cultivation is a land-use activity that maintains woody plant communities in a manner that aligns with biodiversity conservation.
基金Supported by National Natural Science Foundation of China,No.81872036 and No.82060551.
文摘BACKGROUND A previous study showed that irrigation with 100 mL saline reduced residual common bile duct(CBD)stones,which potentially cause recurrent stones after endoscopic retrograde cholangiopancreatography.AIM To determine whether saline irrigation can improve CBD clearance after lithotripsy.METHODS This prospective self-controlled study enrolled patients receiving mechanical lithotripsy for large(>1.2 cm)CBD stones.After occlusion cholangiography confirmed CBD stone clearance,peroral cholangioscopy(POC)was performed to determine clearance scores based on the number of residual stones.The amounts of residual stones spotted via POC were graded on a 5-point scale(score 1,worst;score 5,best).Scores were documented after only stone removal(control)and after irrigation with 50 mL and 100 mL saline,respectively.The stone composition was analyzed using infrared spectroscopy.RESULTS Between October 2018 and January 2020,47 patients had CBD clearance scores of 2.4±1.1 without saline irrigation,3.5±0.7 with 50 mL irrigation,and 4.6±0.6 with 100 mL irrigation(P<0.001).Multivariate analysis showed that CBD diameter>15 mm[odds ratio(OR)=0.08,95%confidence interval(CI):0.01-0.49;P=0.007]and periampullary diverticula(PAD)(OR=6.51,95%CI:1.08-39.21;P=0.041)were independent risk factors for residual stones.Bilirubin pigment stones constituted the main residual stones found in patients with PAD(P=0.004).CONCLUSION Irrigation with 100 mL of saline may not clear all residual CBD stones after lithotripsy,especially in patients with PAD and/or a dilated(>15 mm)CBD.Pigment residual stones are soft and commonly found in patients with PAD.Additional saline irrigation may be required to remove retained stones.
基金National Research Foundation of Korea(NRF)Grant funded by the Korean Government(Ministry of Science and ICT)under Grant No.2017R1A5A1014883。
文摘The challenge in the practical application of rocking foundations is the estimation of its performance,particularly the rotation angle,during a strong earthquake.In this study,the dynamic rocking behavior for a shallow foundation considering structural response was evaluated through two analytical approaches:the conventional soil-foundation-structure interaction(SFSI)governing equation of a single-degree-of-freedom(SDOF)structure on a rocking shallow foundation,and the Housner rocking model(i.e.,a rocking rigid block on a rigid base).Both approaches were validated with dynamic centrifuge tests.The test models consisted of a soft soil deposit,a shallow rectangular foundation,and an SDOF structure dominated by a bending behavior.A total of 11 foundation-structure systems and six seismic waves,including recorded earthquake signals and sinusoidal waves,were utilized.The results showed that the conventional SFSI equation well predicted the maximum rotation during strong earthquakes.However,this method was less accurate regarding the rotational phase information and maximum rotation of the foundation during weak earthquakes.On the other hand,although the modified Housner′s rocking model required five parameters relevant to a soil-foundation-structure system,it overestimated the maximum rotation of the foundation when compared with the results from dynamic centrifuge tests.
文摘In order to test the reliability of γ-GT foci(γ-glutamyltranspeptidase positive hepatocyticfoci) as a preneoplastic marker in AFB-inducedhepatocarcinogenesis, this experiment was car-ried out for a long period after a short-term invivo test model of AFB-induced hepatocarcino-
基金financially supported by the National Natural Science Foundation of China(22001083,52072323,52122211)the“Double-First Class”Foundation of Materials and Intelligent Manufacturing Discipline of Xiamen University。
文摘Metal-based core-shell nanostructures have garnered enduring interest due to their unique properties and functionalities.However,their growth and transformation mechanisms in liquid media remain largely unknown because they lack direct observation of the dynamic growth process with high spatial and temporal resolution.Developing the in situ liquid cell transmission electron microscopy(TEM)technique offers unprecedented real-time imaging and spectroscopy capabilities to directly track the evolution of structural and chemical transformation of metal-based core–shell nanostructures in liquid media under their working condition.Here,this review highlights recent progress in utilizing in situ liquid cell TEM characterization technique in investigating the dynamic evolution of material structure and morphology of metal-based core–shell nanostructures at the nano/atomic scale in real-time.A brief introduction of the development of liquid cells for in situ TEM is first given.Subsequently,recent advances in in situ liquid cell TEM for the fundamental study of growth mechanisms of metal based core–shell nanostructures are discussed.Finally,the challenge and future developments of metalbased core–shell nanostructures for in situ liquid cell TEM are proposed.Our review is anticipated to inspire ongoing interest in revealing unseen growth dynamics of core–shell nanostructures by in situ liquid cell TEM technique.
文摘Ecotourism is a tourism modality intricately linked to the principles of sustainability,due to its natural offer component and environmental education.The objective of this research is to evaluate the perception of ecotourists present on the coast of Yucatan.From a regional approach,the author selected twenty-five community-based ecotourism ventures(CBET)present in the area and analysed the perception of ecotourists through a questionnaire and its respective statistical analysis with non-parametric tests,and developed a general profile of the ecotourist applying a sociodemographic segmentation and based on a geographical segmentation the author compared the perceptions of two populations:national ecotourists and international ecotourists.The data reveal that the profile of the ecotourist on the coast of Yucatan is similar to that postulated in the literature.In terms of environmental perception the author found a significant difference in both populations,and believed that this difference is because the international market is more critical and demanding.In addition,areas of opportunity were documented in the CBETs in the way they carry out their environmental communication.The author concluded that ecotourism in the region is still an activity in consolidation and although it presents great achievements.It is still not possible to qualify it as a sustainable activity.We call for continuing deepening the studies of ecotourism demand and evaluation of perception,through comparative,longitudinal studies and with new variables that allow new test statistics,to contribute new elements to the ecotourism debate.
文摘Hybrid simulation can be a cost effective approach for dynamic testing of structural components at full scale while capturing the system level response through interactions with a numerical model.The dynamic response of a seismically isolated structure depends on the combined characteristics of the ground motion,bearings,and superstructure.Therefore,dynamic full-scale system level tests of isolated structures under realistic dynamic loading conditions are desirable towards a holistic validation of this earthquake protection strategy.Moreover,bearing properties and their ultimate behavior have been shown to be highly dependent on rate-of-loading and scale size effects,especially under extreme loading conditions.Few laboratory facilities can test full-scale seismic isolation bearings under prescribed displacement and/or loading protocols.The adaptation of a full-scale bearing test machine for the implementation of real-time hybrid simulation is presented here with a focus on the challenges encountered in attaining reliable simulation results for large scale dynamic tests.These advanced real-time hybrid simulations of large and complex hybrid models with several thousands of degrees of freedom are some of the first to use high performance parallel computing to rapidly execute the numerical analyses.Challenges in the experimental setup included measured forces contaminated by delay and other systematic control errors in applying desired displacements.Friction and inertial forces generated by the large-scale loading apparatus can affect the accuracy of measured force feedbacks.Reliable results from real-time hybrid simulation requires implementation of compensation algorithms and correction of these various sources of errors.Overall,this research program confirms that real-time hybrid simulation is a viable testing method to experimentally assess the behavior of full-scale isolators while capturing interactions with the numerical models of the superstructure to evaluate system level and in-structure response.
基金This research was supported by the Pacific Earthquake Engineering Research(PEER)Center,Caltrans,and the National Science Foundation(Grant CMMI-1201195,OISE-1445712).Additional support was provided by National Science Foundation(NSF)through computing resources provided by San Diego Supercomputer Center(SDSC)and Texas Advanced Computing Center(TACC).The Wharf layout information was provided by Dr.Arul K.Arulmoli,Principal,Earth Mechanics,Inc.
文摘The OpenSees computational platform has allowed unprecedented opportunities for conducting seismic nonlinear soil-structure interaction simulations.On the geotechnical side,capabilities such as coupled solid-fluid formulations and nonlinear incrementalplasticity approaches allow for representation of the involved dynamic/seismic responses.This paper presents recent research that facilitated such endeavors in terms of response of ground-foundation-structure systems using advanced material modeling techniques and high-performance computing resources.Representative numerical results are shown for large-scale soil-structure systems,and ground modification liquefaction countermeasures.In addition,graphical user interface enabling tools for routine usage of such 3D simulation environments are presented,as an important element in support of wider adoption and practical applications.In this context,Performance-Based Earthquake Engineering(PBEE)analysis of bridge-ground systems is highlighted as an important topical application.
基金financially supported by the National Natural Science Foundation of China(51774051,52072323,52122211)the Science and Technology Planning Project of Hunan Province(2019RS2034)+1 种基金the Hunan High-tech Industry Science and Technology Innovation Leading Plan(2020GK2072)the Changsha City Fund for Distinguished and Innovative Young Scholars(KQ1707014)。
文摘Ni-rich layered oxides are considered promising cathodes for advanced lithium-ion batteries(LIBs)in the future,owing to their high capacity and low cost.However,the issues on structural and interfacial stability of Ni-rich cathodes still pose substantial obstacles in the practical application of advanced LIBs.Here,we employ a one-step method to synthesize a B-doped and La_(4)NiLiO_(8)-coated LiNi_(0.82)5Co_(0.115)Mn_(0.06)O_(2)(BL-1)cathode with reliable structure and interface,for the first time.The La_(4)NiLiO_(8)coating layer can prevent cathodes from electrolyte assault and facilitate Li+diffusion kinetics.Moreover,B-doping can effectively restrain the pernicious H_(2)-H_(3) phase transition and adjust the orientation of primary particles to a radial alignment,which is obstructive to the arise of microcracks induced by the change of anisotropic volume.Specifically,when tested in pouch cells,the BL-1 cathode exhibits outstanding capacity retention of 93.49%after 500 cycles at 1 C.This dual-modification strategy dramatically enhances the stability of the structure and interface for Ni-rich cathode materials,consequently accelerating the commercialization process of high-energy–density LIBs.
文摘BACKGROUND Metoclopramide may be used to treat people suffering from acute migraine.However,no comprehensive investigation on this issue has been recorded.This review will provide more solid evidence for the use of metoclopramide in treating acute migraine.AIM To compare the efficacy of intravenous metoclopramide with other therapies in migraine attack treatment in an emergency department(ED).METHODS We included randomized controlled trials of participants older than 18 years with acute migraine headaches,which included at least one arm that received intravenous(IV)metoclopramide at the ED.A literature search of PubMed,Web of Science,Cochrane Collaboration,and Reference Citation Analysis on December 31,2021 retrieved other drugs or placebo-controlled studies without language limitation.The risk of bias was assessed using the Cochrane risk of bias tool.The primary endpoint was pain reduction at 60 min or closest to 1 h after treatment,as measured by the pain scale.Secondary endpoints included adverse effects or reactions resulting from metoclopramide or comparisons.RESULTS Fourteen trials with a total of 1661 individuals were eligible for review.The risk of bias ranged from low to intermediate.IV metoclopramide administration was not associated with higher pain reduction at 1 h(Standard mean difference[SMD]=-0.03,95%confidence interval[CI]:-0.33-0.28,P=0.87).However,metoclopramide was associated with better pain reduction than placebo(SMD=1.04,95%CI:0.50-1.58,P=0.0002).In addition,side effects were not significantly different between IV metoclopramide and other drugs or placebo(odds ratio[OR]=0.76,95%CI:0.48-1.19,P=0.09 and OR=0.92,95%CI:0.31-2.74,P=0.54,respectively).CONCLUSION Metoclopramide is more effective than placebo in treating migraine in the ED.Despite the observed tendency of decreased side effects,its effectiveness compared to other regimens is poorly understood.More research on this area is needed to treat migraine in acute care settings effectively.
文摘High-temperature superconductivity in ceramic oxides is a new technology in which advances are occurring at a rapid pace. Here, the author describes some properties of a new nano crystalline ceramic Type II superconductor, PbSrCaCuO. Type II superconductors are usually made of metal alloys or complex oxide ceramics. The PSCCO perovskite phase structure was prepared by the conventional solid state reaction technique. In order to show the viability of the proposed method, super-conducting powder was prepared in special furnace. The sample was analyzed by X-ray Diffraction (XRD), Particle size determination, SEM and EDX. The comparison of XRD results with JCPDS files confirmed the orthorhombic structure of the sample with a ≠ b ≠ c and α = β = γ = 90°. Scanning electron microscopy (SEM) studies revealed that its particle size is in the nanometer range. It also confirmed the calculated value of particle size from Debye Scherrer’s formula. EDX spectrum shows the elements of the sample. X-ray instrumental peak broadening analysis was used to evaluate the size and lattice strain by the Williamson-Hall Plot method.
基金This study was funded by National Institutes of Health(UL1TR001442).
文摘SUMMARY In many statistical applications,composite variables are constructed to reduce the number of variables and improve the performances of statistical analyses of these variables,especially when some of the variables are highly correlated.Principal component analysis(PCA)and factor analysis(FA)are generally used for such purposes.If the variables are used as explanatory or independent variables in linear regression analysis,partial least squares(PLS)regression is a better alternative.Unlike PCA and FA,PLS creates composite variables by also taking into account the response,or dependent variable,so that they have higher correlations with the response than composites from their PCA and FA counterparts.In this report,we provide an introduction to this useful approach and illustrate it with data from a real study.