Polymer dielectrics capable of operating efficiently at high electric fields and elevated temperatures are urgently demanded by next-generation electronics and electrical power systems.While inorganic fillers have bee...Polymer dielectrics capable of operating efficiently at high electric fields and elevated temperatures are urgently demanded by next-generation electronics and electrical power systems.While inorganic fillers have been extensively utilized to improved high-temperature capacitive performance of dielectric polymers,the presence of thermodynamically incompatible organic and inorganic components may lead to concern about the long-term stability and also complicate film processing.Herein,zero-dimensional polymer dots with high electron affinity are introduced into photoactive allyl-containing poly(aryl ether sulfone)to form the all-organic polymer composites for hightemperature capacitive energy storage.Upon ultraviolet irradiation,the crosslinked polymer composites with polymer dots are efficient in suppressing electrical conduction at high electric fields and elevated temperatures,which significantly reduces the high-field energy loss of the composites at 200℃.Accordingly,the ultraviolet-irradiated composite film exhibits a discharged energy density of 4.2 J cm^(−3)at 200℃.Along with outstanding cyclic stability of capacitive performance at 200℃,this work provides a promising class of dielectric materials for robust high-performance all-organic dielectric nanocomposites.展开更多
Despite continuous efforts to improve the robustness of cardiac valve implants,neither bioprosthetic nor mechanical valves fulfill both hemodynamic and durability requirements.This study discussed novel flexible leafl...Despite continuous efforts to improve the robustness of cardiac valve implants,neither bioprosthetic nor mechanical valves fulfill both hemodynamic and durability requirements.This study discussed novel flexible leaflet designs,focusing on polymeric materials with proven hemocompatibility,such as polyether ether ketone,of much higher stiffness than native tissue,aiming at optimal valve implants.A biomimetic valve with a single-curvature belly-curve(B-C)was used as a reference for new design variants with a double-curvature B-C with varying radii.Soft(13.2 MPa)and stiff(2.4 GPa)leaflet materials and different thicknesses were studied using lean simulations and in vitro experiments under physiologic hemodynamic conditions.The performance was assessed using opening pressure(OP)and orifice area(OA).The latter was determined by a newly developed automatized image processing tool.Experimental trends are in agreement with simulations and demonstrated that a buckling-inspired double-curvature leaflet design significantly enhances the trileaflet valve opening behavior,which is particularly advantageous for stiffer leaflet materials.Compared to the reference,the best-performing variant showed an OP improvement of 47%and 44%based on simulations and experiments,respectively.In contrast,the achieved mean pressure differential was directly comparable to state-of-the-art bioprosthetic valves.The OA was slightly reduced for new variants but still in the satisfying range.展开更多
Photocatalytic H_(2) evolution from seawater splitting presents a promising approach to tackle the fossil energy crisis and mitigate carbon emission due to the abundant source of seawater and sunlight on the earth.How...Photocatalytic H_(2) evolution from seawater splitting presents a promising approach to tackle the fossil energy crisis and mitigate carbon emission due to the abundant source of seawater and sunlight on the earth.However,the development of efficient photocatalysts for seawater splitting remains a formidable challenge.Herein,a 2D/2D ZnIn_(2)S_(4)/WO_(3)(ZIS/WO_(3))heterojunction nanostructure is fabricated to efficiently separate the photoinduced carriers by steering electron transfer from the conduction band minimum of WO_(3) to the valence band maximum of ZIS via constructing internal electric field.Subsequently,plasmonic Au nanoparticles(NPs)as a novel photosensitizer and a reduction cocatalyst are anchored on ZIS/WO_(3) surface to further enhance the optical absorption of ZIS/WO_(3) heterojunction and accelerate the catalytic conversion.The obtained Au/ZIS/WO_(3) photocatalyst exhibits an outstanding H_(2) evolution rate of 2610.6 or 3566.3μmol g^(-1)h~(-1)from seawater splitting under visible or full-spectrum light irradiation,respectively.These rates represent an impressive increase of approximately 7.3-and 6,6-fold compared to those of ZIS under the illumination of the same light source.The unique 2D/2D structure,internal electric field,and plasmonic metal modification together boost the photocatalytic H_(2) evolution rate of Au/ZIS/WO_(3),making it even comparable to H_(2) evolution from pure water splitting.The present work sheds light on the development of efficient photocatalysts for seawater splitting.展开更多
Mg-Y-Zn-Al alloys processed by rapidly solidified ribbon consolidation(RSRC)technique exhibit an exceptional mechanical performance indicating promising application potential.This material has a bimodal microstructure...Mg-Y-Zn-Al alloys processed by rapidly solidified ribbon consolidation(RSRC)technique exhibit an exceptional mechanical performance indicating promising application potential.This material has a bimodal microstructure consisting of fine recrystallized and coarse non-recrystallized grains with solute-rich stacking faults forming cluster arranged layers(CALs)and nanoplates(CANaPs),or complete long period stacking ordered(LPSO)phase.In order to reveal the deformation mechanisms,in-situ synchrotron X-ray diffraction line profile analysis was employed for a detailed study of the dislocation arrangement created during tension in Mg-0.9%Zn-2.05%Y-0.15%Al(at%)alloy.For uncovering the effect of the initial microstructure on the mechanical performance,additional samples were obtained by annealing of the as-consolidated specimen at 300 and 400℃ for 2 h.The heat treatment at 300℃ had no significant effect on the initial microstructure,its evolution during tension and,thus,the overall deformation behavior under tensile loading.On the other hand,annealing at 400℃ resulted in a significant increase of the recrystallized grains fraction and a decrease of the dislocation density,leading to only minor degradation of the mechanical strength.The maximum dislocation density at the failure of the samples corresponding to the plastic strain of 10-25% was estimated to be about 16-20×10^(14)m^(-2).The diffraction profile analysis indicated that most dislocations formed during tension were of non-basal and pyramidal types,what was also in agreement with the Schmid factor values revealed independently from orientation maps.It was also shown that the dislocation-induced Taylor hardening was much lower below the plastic strain of 3% than above this value,which was explained by a model of the interaction between prismatic dislocations and CANaPs/LPSO plates.展开更多
Efficient cellular fusion of mononuclear precursors is the prerequisite for the generation of fully functional multinucleated bone-resorbing osteoclasts.However,the exact molecular factors and mechanisms controlling o...Efficient cellular fusion of mononuclear precursors is the prerequisite for the generation of fully functional multinucleated bone-resorbing osteoclasts.However,the exact molecular factors and mechanisms controlling osteoclast fusion remain incompletely understood.Here we identify RANKL-mediated activation of caspase-8 as early key event during osteoclast fusion.展开更多
The reconstruction of images from their corresponding noisy Radon transform is a typical example of an ill-posed linear inverse problem as arising in the application of computerized tomography(CT).As the(naive)solutio...The reconstruction of images from their corresponding noisy Radon transform is a typical example of an ill-posed linear inverse problem as arising in the application of computerized tomography(CT).As the(naive)solution does not depend on the measured data continuously,regularization is needed to reestablish a continuous dependence.In this work,we investigate simple,but yet still provably convergent approaches to learning linear regularization methods from data.More specifically,we analyze two approaches:one generic linear regularization that learns how to manipulate the singular values of the linear operator in an extension of our previous work,and one tailored approach in the Fourier domain that is specific to CT-reconstruction.We prove that such approaches become convergent regularization methods as well as the fact that the reconstructions they provide are typically much smoother than the training data they were trained on.Finally,we compare the spectral as well as the Fourier-based approaches for CT-reconstruction numerically,discuss their advantages and disadvantages and investigate the effect of discretization errors at differentresolutions.展开更多
Enhanced osteoclastogenesis and osteoclast activity contribute to the development of osteoporosis,which is characterized by increased bone resorption and inadequate bone formation.As novel antiosteoporotic therapeutic...Enhanced osteoclastogenesis and osteoclast activity contribute to the development of osteoporosis,which is characterized by increased bone resorption and inadequate bone formation.As novel antiosteoporotic therapeutics are needed,understanding the genetic regulation of human osteoclastogenesis could help identify potential treatment targets.This study aimed to provide an overview of transcriptional reprogramming during human osteoclast differentiation.Osteoclasts were differentiated from CD14+monocytes from eight female donors.RNA sequencing during differentiation revealed 8980 differentially expressed genes grouped into eight temporal patterns conserved across donors.These patterns revealed distinct molecular functions associated with postmenopausal osteoporosis susceptibility genes based on RNA from iliac crest biopsies and bone mineral density SNPs.Network analyses revealed mutual dependencies between temporal expression patterns and provided insight into subtype-specific transcriptional networks.The donor-specific expression patterns revealed genes at the monocyte stage,such as filamin B(FLNB)and oxidized low-density lipoprotein receptor 1(OLR1,encoding LOX-1),that are predictive of the resorptive activity of mature osteoclasts.The expression of differentially expressed G-protein coupled receptors was strong during osteoclast differentiation,and these receptors are associated with bone mineral density SNPs,suggesting that they play a pivotal role in osteoclast differentiation and activity.The regulatory effects of three differentially expressed G-protein coupled receptors were exemplified by in vitro pharmacological modulation of complement 5 A receptor 1(C5AR1),somatostatin receptor 2(SSTR2),and free fatty acid receptor 4(FFAR4/GPR120).Activating C5AR1 enhanced osteoclast formation,while activating SSTR2 decreased the resorptive activity of mature osteoclasts,and activating FFAR4 decreased both the number and resorptive activity of mature osteoclasts.In conclusion,we report the occurrence of transcriptional reprogramming during human osteoclast differentiation and identified SSTR2 and FFAR4 as antiresorptive G-protein coupled receptors and FLNB and LOX-1 as potential molecular markers of osteoclast activity.These data can help future investigations identify molecular regulators of osteoclast differentiation and activity and provide the basis for novel antiosteoporotic targets.展开更多
The stem barks of Prunus africana are used in the treatment of the benign prostate. Cameroon is one of the important exporters of the barks. Despite the important measures adopted in Cameroon for sustaining its harves...The stem barks of Prunus africana are used in the treatment of the benign prostate. Cameroon is one of the important exporters of the barks. Despite the important measures adopted in Cameroon for sustaining its harvesting, some many chalenges still remain. The objective of this work is to refine the forest management parameters in relation to P. africana in the regions of Adamaoua and the South-West by developing a volume rate which makes it possible to estimate the production for a new stem. The work took place in two phases: in the South-West in 2010 and in Adamaoua in 2011. Data collection used the semi-direct method, while the cubing equation was deduced by the multiple linear regression method. Two models for volume estimation and three models for mass prediction were developed. The predictive parameters retained are diameter, height of the bole and thickness of the bark. Results show that the average mass of the dry bark for a given P. africana tree species is 27.55 ± 14.44 kg and this varies according to the site. The strong adjusted coefficient of determination (adjusted R2) observed illustrates the reliability of the proposed models. These models provide a reliable tool that can be adopted as a standard in Cameroon for P. africana.展开更多
在城市地区发生的大地震可以造成重大人员伤亡,引发社会和经济灾难。地震预警(Earthquake Early Warning,EEW)可以提供秒到分钟的警报,让人们转移到安全区,使工厂停工,车辆减速和刹车。目前世界上只在少数国家使用传统的地震台网和大地...在城市地区发生的大地震可以造成重大人员伤亡,引发社会和经济灾难。地震预警(Earthquake Early Warning,EEW)可以提供秒到分钟的警报,让人们转移到安全区,使工厂停工,车辆减速和刹车。目前世界上只在少数国家使用传统的地震台网和大地测量观测网运行EEW系统。智能手机比传统地震台网更为广泛和普及,它内置了可检测地震的加速度计。我们开发了一种新的测震系统称为MyShake,它利用智能手机内置传感器来收集数据并分析地震。智能手机MyShake系统可以从日常的各种震动中检测到距手机10km或以内的5级地震。这些数据汇集到观测中心,经过一定的算法处理,可以实时测定地震的位置和震级,发出地震预警信息,证明我们的理念是可行的。对没有地震预警系统的区域,MyShake系统可提供地震预警,而对有预警系统的区域,MyShake系统是对原系统预警能力的补充和增强。此外,该系统地震波形记录可以用来提供快速地震烈度图,以评估地震对建筑物的影响,还可以获取地球内部浅层结构图像和地震破裂过程。展开更多
Although acupuncture theory is a fundamental part of the Huangdi Neijing, the clinical application of the needle therapy in ancient China was always a limited one. From early times there have been warnings that acupun...Although acupuncture theory is a fundamental part of the Huangdi Neijing, the clinical application of the needle therapy in ancient China was always a limited one. From early times there have been warnings that acupuncture might do harm. In books like Zhang Zhongjing＇s Shanghanlun it plays only a marginal role. Among the 400 emperors in Chinese history, acupuncture was hardly ever applied. After Xu Dachun called acupuncture a ＂lost tradition＂ in 1757, the abolition of acupuncture and moxibustion from the Imperial Medical Academy in 1822 was a radical, but consequent act. When traditional Chinese medicine was revived after 1954, the ＂New Acupuncture＂ was completely different from what it had been in ancient China. The conclusion, however, is a positive one： The best time acupuncture ever had was not the Song dynasty or Yuan dynasty, but is now - and the future of acupuncture does not lie in old scripts, but in ourselves.展开更多
Idiopathic achalasia is a rare primary motility disorder of the esophagus. The classical features are incomplete relaxation of a frequently hypertensive lower esophageal sphincter (LES) and a lack of peristalsis in th...Idiopathic achalasia is a rare primary motility disorder of the esophagus. The classical features are incomplete relaxation of a frequently hypertensive lower esophageal sphincter (LES) and a lack of peristalsis in the tubular esophagus. These motor abnormalities lead to dysphagia, stasis, regurgitation, weight loss, or secondary respiratory complications. Although major strides have been made in understanding the pathogenesis of this rare disorder, including a probable autoimmune mediated destruction of inhibitory neurons in response to an unknown insult in genetically susceptible individuals, a definite trigger has not been identified. The diagnosis of achalasia is suggested by clinical features and conf irmed by further diagnostic tests, such as esophagogastroduodenoscopy (EGD), manometry or barium swallow. These studies are not only used to exclude pseudoachalasia, but also might help to categorize the disease by severity or clinical subtype. Recent advances in diagnostic methods, including high resolution manometry (HRM), might allow prediction of treatment responses. The primary treatments for achieving long-term symptom relief are surgery and endoscopic methods. Although limited high-quality data exist, it appears that laparoscopic Heller myotomy with partial fundoplication is superior to endoscopic methods in achieving long-term relief of symptoms in the majority of patients. However, the current clinical approach to achalasia will depend not only on patients' characteristics and clinical subtypes of the disease, but also on local expertise and patient preferences.展开更多
The Yinyang concept and the Wuxing concept are two basic concepts of Chinese philosophy,as well as of traditional Chinese medicine(TCM).When I started studying TCM in Shanghai 30 years ago,I met the Yinyang concept an...The Yinyang concept and the Wuxing concept are two basic concepts of Chinese philosophy,as well as of traditional Chinese medicine(TCM).When I started studying TCM in Shanghai 30 years ago,I met the Yinyang concept and the展开更多
Background The Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery （SYNTAX）-score is a validated tool for risk stratification and revascularization strategy selection in patients with c...Background The Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery （SYNTAX）-score is a validated tool for risk stratification and revascularization strategy selection in patients with complex coronary artery disease. The aim of this study was to analyse its age-related prognostic value. Methods SYNTAX-score was calculated in 1331 all-comer patients undergoing percutaneous coronary intervention （PCI）： 463 patients ≥ 75 years and 868 patients 〈 75 years. Outcomes of interest were all-cause mortality at one and two years. Results A significant interaction of age and SYNTAX-score for mortality was observed at two-year （Pinteraction= 0.019） but not at one-year follow-up （Pinteraction= 0.594）. In multivariable analysis, SYNTAX-score independently predicted 1-year mortality in both age groups （〈 75 years, hazard ratio （HR）： 1.43, 95% confidence intervals （CI）： 1.03-2.00, P = 0.034; and 〉 75 years, HR： 1.37, 95% CI： 1.01-1.85, P = 0.042）, but only two-year mortality among younger patients （〈 75 years, HR： 1.33, 95% CI： 1.01-1.76, P = 0.041; and ≥ 75 years, HR： 1.11, 95% CI： 0.87-1.41, P = 0.394）. SYNTAX-score tertiles were useful to stratify 1-year mortality in both, patients 〈 75 years （SYNTAX-score 〈 9, 3.8%; 9-20, 5.3%; 〉 20, 10.3%; P = 0.004） and 〉 75 years （SYNTAX-score 〈 11, 5.7%; 11-22.5, 16.1%; 〉 22.5, 18.7%; P = 0.003）, but two-year mortality only among patients 〈 75 years （SYNTAX-score 〈 9, 6.5%; 9-20, 7.6%; ≥ 20, 15%; P 〈 0.001） and not among ≥ 75 years old patients （SYNTAX-score 〈 11, 19.4%; 11-22.5, 26.3%; _〉 22.5, 27.9%; P = 0.138）. Conclusions Age modi- fies the impact of the SYNTAX-score on longer-term mortality after PCI. Among patients 〈 75 years, the SYNTAX-score independently predicts the risk of death at one and two years after PCI, while among patients 〉 75 years its predictive role is limited to the first year after PCI. Further studies are needed to evaluate the value of SYNTAX-score for selecting the most appropriate revascularization strategy among elderly patients.展开更多
基金the National Natural Science Foundation of China(No.51973080,92066104).
文摘Polymer dielectrics capable of operating efficiently at high electric fields and elevated temperatures are urgently demanded by next-generation electronics and electrical power systems.While inorganic fillers have been extensively utilized to improved high-temperature capacitive performance of dielectric polymers,the presence of thermodynamically incompatible organic and inorganic components may lead to concern about the long-term stability and also complicate film processing.Herein,zero-dimensional polymer dots with high electron affinity are introduced into photoactive allyl-containing poly(aryl ether sulfone)to form the all-organic polymer composites for hightemperature capacitive energy storage.Upon ultraviolet irradiation,the crosslinked polymer composites with polymer dots are efficient in suppressing electrical conduction at high electric fields and elevated temperatures,which significantly reduces the high-field energy loss of the composites at 200℃.Accordingly,the ultraviolet-irradiated composite film exhibits a discharged energy density of 4.2 J cm^(−3)at 200℃.Along with outstanding cyclic stability of capacitive performance at 200℃,this work provides a promising class of dielectric materials for robust high-performance all-organic dielectric nanocomposites.
基金provided by Board of the Swiss Federal Institutes of TechnologyUniversitat Zürichthe Laboratory of Composite Materials and Adaptive structures。
文摘Despite continuous efforts to improve the robustness of cardiac valve implants,neither bioprosthetic nor mechanical valves fulfill both hemodynamic and durability requirements.This study discussed novel flexible leaflet designs,focusing on polymeric materials with proven hemocompatibility,such as polyether ether ketone,of much higher stiffness than native tissue,aiming at optimal valve implants.A biomimetic valve with a single-curvature belly-curve(B-C)was used as a reference for new design variants with a double-curvature B-C with varying radii.Soft(13.2 MPa)and stiff(2.4 GPa)leaflet materials and different thicknesses were studied using lean simulations and in vitro experiments under physiologic hemodynamic conditions.The performance was assessed using opening pressure(OP)and orifice area(OA).The latter was determined by a newly developed automatized image processing tool.Experimental trends are in agreement with simulations and demonstrated that a buckling-inspired double-curvature leaflet design significantly enhances the trileaflet valve opening behavior,which is particularly advantageous for stiffer leaflet materials.Compared to the reference,the best-performing variant showed an OP improvement of 47%and 44%based on simulations and experiments,respectively.In contrast,the achieved mean pressure differential was directly comparable to state-of-the-art bioprosthetic valves.The OA was slightly reduced for new variants but still in the satisfying range.
基金supported by the National Natural Science Foundation of China(21872104,21501131,21978216 and 22272082)the Natural Science Foundation of Tianjin for Distinguished Young Scholar(20JCJQJC00150)the Analytical&Testing Center of Tiangong University for PL work。
文摘Photocatalytic H_(2) evolution from seawater splitting presents a promising approach to tackle the fossil energy crisis and mitigate carbon emission due to the abundant source of seawater and sunlight on the earth.However,the development of efficient photocatalysts for seawater splitting remains a formidable challenge.Herein,a 2D/2D ZnIn_(2)S_(4)/WO_(3)(ZIS/WO_(3))heterojunction nanostructure is fabricated to efficiently separate the photoinduced carriers by steering electron transfer from the conduction band minimum of WO_(3) to the valence band maximum of ZIS via constructing internal electric field.Subsequently,plasmonic Au nanoparticles(NPs)as a novel photosensitizer and a reduction cocatalyst are anchored on ZIS/WO_(3) surface to further enhance the optical absorption of ZIS/WO_(3) heterojunction and accelerate the catalytic conversion.The obtained Au/ZIS/WO_(3) photocatalyst exhibits an outstanding H_(2) evolution rate of 2610.6 or 3566.3μmol g^(-1)h~(-1)from seawater splitting under visible or full-spectrum light irradiation,respectively.These rates represent an impressive increase of approximately 7.3-and 6,6-fold compared to those of ZIS under the illumination of the same light source.The unique 2D/2D structure,internal electric field,and plasmonic metal modification together boost the photocatalytic H_(2) evolution rate of Au/ZIS/WO_(3),making it even comparable to H_(2) evolution from pure water splitting.The present work sheds light on the development of efficient photocatalysts for seawater splitting.
基金financially supported by the International Visegrad Fund(project V4-Japan Joint Research Program,Ref.JP3936)the National Research,Development and Innovation Office(Contract No.:2019-2.1.7-ERANET-2021-00030)+1 种基金Support by the Ministry of Education,Youth and Sports of Czech Republic in the framework of Visegrad Group(V4)-Japan Joint Research Program-Advanced Materials under grant No.8F21011supported by JST SICORP Grant Number JPMJSC2109,Japan。
文摘Mg-Y-Zn-Al alloys processed by rapidly solidified ribbon consolidation(RSRC)technique exhibit an exceptional mechanical performance indicating promising application potential.This material has a bimodal microstructure consisting of fine recrystallized and coarse non-recrystallized grains with solute-rich stacking faults forming cluster arranged layers(CALs)and nanoplates(CANaPs),or complete long period stacking ordered(LPSO)phase.In order to reveal the deformation mechanisms,in-situ synchrotron X-ray diffraction line profile analysis was employed for a detailed study of the dislocation arrangement created during tension in Mg-0.9%Zn-2.05%Y-0.15%Al(at%)alloy.For uncovering the effect of the initial microstructure on the mechanical performance,additional samples were obtained by annealing of the as-consolidated specimen at 300 and 400℃ for 2 h.The heat treatment at 300℃ had no significant effect on the initial microstructure,its evolution during tension and,thus,the overall deformation behavior under tensile loading.On the other hand,annealing at 400℃ resulted in a significant increase of the recrystallized grains fraction and a decrease of the dislocation density,leading to only minor degradation of the mechanical strength.The maximum dislocation density at the failure of the samples corresponding to the plastic strain of 10-25% was estimated to be about 16-20×10^(14)m^(-2).The diffraction profile analysis indicated that most dislocations formed during tension were of non-basal and pyramidal types,what was also in agreement with the Schmid factor values revealed independently from orientation maps.It was also shown that the dislocation-induced Taylor hardening was much lower below the plastic strain of 3% than above this value,which was explained by a model of the interaction between prismatic dislocations and CANaPs/LPSO plates.
基金supported by the Bayerische Forschungsstiftung to B.K.the Deutsche Forschungsgemeinschaft (CRC1181 to G.K.and G.S.+3 种基金SCHE 2062/1-1 to C.S.)funded by the Wellcome Trust Investigator Award (107964/Z/15/Z)the UK Dementia Research Institutefunded by BBSRC Discovery Fellowship (BB/T009543/1)。
文摘Efficient cellular fusion of mononuclear precursors is the prerequisite for the generation of fully functional multinucleated bone-resorbing osteoclasts.However,the exact molecular factors and mechanisms controlling osteoclast fusion remain incompletely understood.Here we identify RANKL-mediated activation of caspase-8 as early key event during osteoclast fusion.
基金the support of the German Research Foundation,projects BU 2327/19-1 and MO 2962/7-1support from the EPSRC grant EP/R513106/1support from the Alan Turing Institute.
文摘The reconstruction of images from their corresponding noisy Radon transform is a typical example of an ill-posed linear inverse problem as arising in the application of computerized tomography(CT).As the(naive)solution does not depend on the measured data continuously,regularization is needed to reestablish a continuous dependence.In this work,we investigate simple,but yet still provably convergent approaches to learning linear regularization methods from data.More specifically,we analyze two approaches:one generic linear regularization that learns how to manipulate the singular values of the linear operator in an extension of our previous work,and one tailored approach in the Fourier domain that is specific to CT-reconstruction.We prove that such approaches become convergent regularization methods as well as the fact that the reconstructions they provide are typically much smoother than the training data they were trained on.Finally,we compare the spectral as well as the Fourier-based approaches for CT-reconstruction numerically,discuss their advantages and disadvantages and investigate the effect of discretization errors at differentresolutions.
基金funded by grants from the Novo Nordisk Foundation (NNF18OC0052699) (M.S.H.) and NNF18OC0055047 (M.F.)the Region of Southern Denmark (ref: 18/17553 (M.S.H.))+3 种基金Odense University Hospital (ref: A3147) (M.F.)a faculty fellowship from the University of Southern Denmark (K.M.), the Lundbeck Foundation (ref: R335-2019-2195) (K.M.and A.R.)an Academy of Medical Sciences Springboard Award supported by the British Heart Foundation, Diabetes UK, the Global Challenges Research Fund, the Government Department of Business, Energy and Industrial Strategy and the Wellcome Trust (ref: SBF004 | 1034, C.M.G)a Sir Henry Dale Fellowship jointly funded by the Wellcome Trust and the Royal Society (Grant Number 224155/Z/21/Z to C.M.G.).
文摘Enhanced osteoclastogenesis and osteoclast activity contribute to the development of osteoporosis,which is characterized by increased bone resorption and inadequate bone formation.As novel antiosteoporotic therapeutics are needed,understanding the genetic regulation of human osteoclastogenesis could help identify potential treatment targets.This study aimed to provide an overview of transcriptional reprogramming during human osteoclast differentiation.Osteoclasts were differentiated from CD14+monocytes from eight female donors.RNA sequencing during differentiation revealed 8980 differentially expressed genes grouped into eight temporal patterns conserved across donors.These patterns revealed distinct molecular functions associated with postmenopausal osteoporosis susceptibility genes based on RNA from iliac crest biopsies and bone mineral density SNPs.Network analyses revealed mutual dependencies between temporal expression patterns and provided insight into subtype-specific transcriptional networks.The donor-specific expression patterns revealed genes at the monocyte stage,such as filamin B(FLNB)and oxidized low-density lipoprotein receptor 1(OLR1,encoding LOX-1),that are predictive of the resorptive activity of mature osteoclasts.The expression of differentially expressed G-protein coupled receptors was strong during osteoclast differentiation,and these receptors are associated with bone mineral density SNPs,suggesting that they play a pivotal role in osteoclast differentiation and activity.The regulatory effects of three differentially expressed G-protein coupled receptors were exemplified by in vitro pharmacological modulation of complement 5 A receptor 1(C5AR1),somatostatin receptor 2(SSTR2),and free fatty acid receptor 4(FFAR4/GPR120).Activating C5AR1 enhanced osteoclast formation,while activating SSTR2 decreased the resorptive activity of mature osteoclasts,and activating FFAR4 decreased both the number and resorptive activity of mature osteoclasts.In conclusion,we report the occurrence of transcriptional reprogramming during human osteoclast differentiation and identified SSTR2 and FFAR4 as antiresorptive G-protein coupled receptors and FLNB and LOX-1 as potential molecular markers of osteoclast activity.These data can help future investigations identify molecular regulators of osteoclast differentiation and activity and provide the basis for novel antiosteoporotic targets.
文摘The stem barks of Prunus africana are used in the treatment of the benign prostate. Cameroon is one of the important exporters of the barks. Despite the important measures adopted in Cameroon for sustaining its harvesting, some many chalenges still remain. The objective of this work is to refine the forest management parameters in relation to P. africana in the regions of Adamaoua and the South-West by developing a volume rate which makes it possible to estimate the production for a new stem. The work took place in two phases: in the South-West in 2010 and in Adamaoua in 2011. Data collection used the semi-direct method, while the cubing equation was deduced by the multiple linear regression method. Two models for volume estimation and three models for mass prediction were developed. The predictive parameters retained are diameter, height of the bole and thickness of the bark. Results show that the average mass of the dry bark for a given P. africana tree species is 27.55 ± 14.44 kg and this varies according to the site. The strong adjusted coefficient of determination (adjusted R2) observed illustrates the reliability of the proposed models. These models provide a reliable tool that can be adopted as a standard in Cameroon for P. africana.
文摘在城市地区发生的大地震可以造成重大人员伤亡,引发社会和经济灾难。地震预警(Earthquake Early Warning,EEW)可以提供秒到分钟的警报,让人们转移到安全区,使工厂停工,车辆减速和刹车。目前世界上只在少数国家使用传统的地震台网和大地测量观测网运行EEW系统。智能手机比传统地震台网更为广泛和普及,它内置了可检测地震的加速度计。我们开发了一种新的测震系统称为MyShake,它利用智能手机内置传感器来收集数据并分析地震。智能手机MyShake系统可以从日常的各种震动中检测到距手机10km或以内的5级地震。这些数据汇集到观测中心,经过一定的算法处理,可以实时测定地震的位置和震级,发出地震预警信息,证明我们的理念是可行的。对没有地震预警系统的区域,MyShake系统可提供地震预警,而对有预警系统的区域,MyShake系统是对原系统预警能力的补充和增强。此外,该系统地震波形记录可以用来提供快速地震烈度图,以评估地震对建筑物的影响,还可以获取地球内部浅层结构图像和地震破裂过程。
文摘Although acupuncture theory is a fundamental part of the Huangdi Neijing, the clinical application of the needle therapy in ancient China was always a limited one. From early times there have been warnings that acupuncture might do harm. In books like Zhang Zhongjing＇s Shanghanlun it plays only a marginal role. Among the 400 emperors in Chinese history, acupuncture was hardly ever applied. After Xu Dachun called acupuncture a ＂lost tradition＂ in 1757, the abolition of acupuncture and moxibustion from the Imperial Medical Academy in 1822 was a radical, but consequent act. When traditional Chinese medicine was revived after 1954, the ＂New Acupuncture＂ was completely different from what it had been in ancient China. The conclusion, however, is a positive one： The best time acupuncture ever had was not the Song dynasty or Yuan dynasty, but is now - and the future of acupuncture does not lie in old scripts, but in ourselves.
文摘Idiopathic achalasia is a rare primary motility disorder of the esophagus. The classical features are incomplete relaxation of a frequently hypertensive lower esophageal sphincter (LES) and a lack of peristalsis in the tubular esophagus. These motor abnormalities lead to dysphagia, stasis, regurgitation, weight loss, or secondary respiratory complications. Although major strides have been made in understanding the pathogenesis of this rare disorder, including a probable autoimmune mediated destruction of inhibitory neurons in response to an unknown insult in genetically susceptible individuals, a definite trigger has not been identified. The diagnosis of achalasia is suggested by clinical features and conf irmed by further diagnostic tests, such as esophagogastroduodenoscopy (EGD), manometry or barium swallow. These studies are not only used to exclude pseudoachalasia, but also might help to categorize the disease by severity or clinical subtype. Recent advances in diagnostic methods, including high resolution manometry (HRM), might allow prediction of treatment responses. The primary treatments for achieving long-term symptom relief are surgery and endoscopic methods. Although limited high-quality data exist, it appears that laparoscopic Heller myotomy with partial fundoplication is superior to endoscopic methods in achieving long-term relief of symptoms in the majority of patients. However, the current clinical approach to achalasia will depend not only on patients' characteristics and clinical subtypes of the disease, but also on local expertise and patient preferences.
文摘The Yinyang concept and the Wuxing concept are two basic concepts of Chinese philosophy,as well as of traditional Chinese medicine(TCM).When I started studying TCM in Shanghai 30 years ago,I met the Yinyang concept and the
文摘Background The Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery （SYNTAX）-score is a validated tool for risk stratification and revascularization strategy selection in patients with complex coronary artery disease. The aim of this study was to analyse its age-related prognostic value. Methods SYNTAX-score was calculated in 1331 all-comer patients undergoing percutaneous coronary intervention （PCI）： 463 patients ≥ 75 years and 868 patients 〈 75 years. Outcomes of interest were all-cause mortality at one and two years. Results A significant interaction of age and SYNTAX-score for mortality was observed at two-year （Pinteraction= 0.019） but not at one-year follow-up （Pinteraction= 0.594）. In multivariable analysis, SYNTAX-score independently predicted 1-year mortality in both age groups （〈 75 years, hazard ratio （HR）： 1.43, 95% confidence intervals （CI）： 1.03-2.00, P = 0.034; and 〉 75 years, HR： 1.37, 95% CI： 1.01-1.85, P = 0.042）, but only two-year mortality among younger patients （〈 75 years, HR： 1.33, 95% CI： 1.01-1.76, P = 0.041; and ≥ 75 years, HR： 1.11, 95% CI： 0.87-1.41, P = 0.394）. SYNTAX-score tertiles were useful to stratify 1-year mortality in both, patients 〈 75 years （SYNTAX-score 〈 9, 3.8%; 9-20, 5.3%; 〉 20, 10.3%; P = 0.004） and 〉 75 years （SYNTAX-score 〈 11, 5.7%; 11-22.5, 16.1%; 〉 22.5, 18.7%; P = 0.003）, but two-year mortality only among patients 〈 75 years （SYNTAX-score 〈 9, 6.5%; 9-20, 7.6%; ≥ 20, 15%; P 〈 0.001） and not among ≥ 75 years old patients （SYNTAX-score 〈 11, 19.4%; 11-22.5, 26.3%; _〉 22.5, 27.9%; P = 0.138）. Conclusions Age modi- fies the impact of the SYNTAX-score on longer-term mortality after PCI. Among patients 〈 75 years, the SYNTAX-score independently predicts the risk of death at one and two years after PCI, while among patients 〉 75 years its predictive role is limited to the first year after PCI. Further studies are needed to evaluate the value of SYNTAX-score for selecting the most appropriate revascularization strategy among elderly patients.
