The tensile strength at the rock-concrete interface is one of the crucial factors controlling the failure mechanisms of structures,such as concrete gravity dams.Despite the critical importance of the failure mechanism...The tensile strength at the rock-concrete interface is one of the crucial factors controlling the failure mechanisms of structures,such as concrete gravity dams.Despite the critical importance of the failure mechanism and tensile strength of rock-concrete interfaces,understanding of these factors remains very limited.This study investigated the tensile strength and fracturing processes at rock-mortar interfaces subjected to direct and indirect tensile loadings.Digital image correlation(DIC)and acoustic emission(AE)techniques were used to monitor the failure mechanisms of specimens subjected to direct tension and indirect loading(Brazilian tests).The results indicated that the direct tensile strength of the rock-mortar specimens was lower than their indirect tensile strength,with a direct/indirect tensile strength ratio of 65%.DIC strain field data and moment tensor inversions(MTI)of AE events indicated that a significant number of shear microcracks occurred in the specimens subjected to the Brazilian test.The presence of these shear microcracks,which require more energy to break,resulted in a higher tensile strength during the Brazilian tests.In contrast,microcracks were predominantly tensile in specimens subjected to direct tension,leading to a lower tensile strength.Spatiotemporal monitoring of the cracking processes in the rock-mortar interfaces revealed that they show AE precursors before failure under the Brazilian test,whereas they show a minimal number of AE events before failure under direct tension.Due to different microcracking mechanisms,specimens tested under Brazilian tests showed lower roughness with flatter fracture surfaces than those tested under direct tension with jagged and rough fracture surfaces.The results of this study shed light on better understanding the micromechanics of damage in the rock-concrete interfaces for a safer design of engineering structures.展开更多
We investigate the accuracy and robustness of moment tensor(MT)and stress inversion solutions derived from acoustic emissions(AEs)during the laboratory fracturing of prismatic Barre granite specimens.Pre-cut flaws in ...We investigate the accuracy and robustness of moment tensor(MT)and stress inversion solutions derived from acoustic emissions(AEs)during the laboratory fracturing of prismatic Barre granite specimens.Pre-cut flaws in the specimens introduce a complex stress field,resulting in a spatial and temporal variation of focal mechanisms.Specifically,we consider two experimental setups:(1)where the rock is loaded in compression to generate primarily shear-type fractures and(2)where the material is loaded in indirect tension to generate predominantly tensile-type fractures.In each test,we first decompose AE moment tensors into double-couple(DC)and non-DC terms and then derive unambiguous normal and slip vectors using k-means clustering and an unstructured damped stress inversion algorithm.We explore temporal and spatial distributions of DC and non-DC events at different loading levels.The majority of the DC and the tensile non-DC events cluster around the pre-cut flaws,where macro-cracks later develop.Results of stress inversion are verified against the stress field from finite element(FE)modeling.A good agreement is found between the experimentally derived and numerically simulated stress orientations.To the best of the authors’knowledge,this work presents the first case where stress inversion methodologies are validated by numerical simulations at laboratory scale and under highly heterogeneous stress distributions.展开更多
Attiéké is fermented cassava semolina steamed and consumed with proteins and vegetables. From Ivorian traditional origin, its popularity is increasing in Africa and production networks are developing. Howeve...Attiéké is fermented cassava semolina steamed and consumed with proteins and vegetables. From Ivorian traditional origin, its popularity is increasing in Africa and production networks are developing. However, the growth of attiéké industry is still curbed by lack of technical skills of producers and irregular quality, depending on cassava variety, processing and inoculum. In the present study, a traditional inoculum and four cassava varieties (two improved local (IAC and Bonoua) and two improved sweet ones from Nigeria (Olekanga and TMS 4 (2) 1425)) were used for producing attiéké Ebrié. For the sensorial evaluation of prepared attiéké, qualitative sensory profiling was used. The sensory quality descriptors where quantitatively measured by a trained sensory panel. With this method the most important quality criteria of attiéké were judged. These quality criteria were selected with the aid of surveys on its production and consumption. The relationships between sensory attributes of the four attiéké prepared of the different cassava varieties and biochemical characteristics were studied. Sensory analysis revealed that the four attiéké were cream-colored products with sweet and/or sour tastes, made of cohesive and well-formed grains of different sizes, with an odor of fermentation specific to attiéké and showing a firm texture. The differences between sensory profiles of the four attiéké produced from four cassava varieties (12 months growth) concern only some descriptors of quality. Pearson correlation coefficients between physicochemical descriptors of quality showed that biochemical parameters may help predict organoleptic characteristics of attiéké Ebrié (pH-size of grains: r = 0.99;pH-acidity: r = ?0.92;acidity-rounded grains: r = ?0.98: starch-cohesion between grains: r = ?0.96;starch-sweet: r = ?0.95;starch-granulous: r = 0.97, total sugar-yellow color: r = 0.96;total sugar-aroma of attiéké: r = 0.96;reducing sugar-odor of attiéké: r = 0.95;cyanide-fibrous: r = 0.95).展开更多
As a diagnostic method,magnetic resonance imaging(MRI)is not allowed to be used in patients with medical implants,including both active implants(such as cardiac defibrillators or deep brain stimulators)and passive imp...As a diagnostic method,magnetic resonance imaging(MRI)is not allowed to be used in patients with medical implants,including both active implants(such as cardiac defibrillators or deep brain stimulators)and passive implants(such as orthopedics implants and support).MRI imaging scanning can produce magnetic fields,which will produce concentrated electromagnetic induction on metal edges of the implants,such as electrodes.The magnetic field can also significantly increase the temperature of surrounding tissues.Besides,the currents and voltage produced by active implants when exposed to MRI scanning can lead to damage and malfunction of pulse generators.Therefore,patients with medical implants cannot receive MRI as a diagnostic method.This safety protocol prevents a large group of patients from receiving MRI diagnosis.This leads to the conclusion that the safety evaluation of implants under MRI environment requires the combination of accurate data analysis and experimental techniques so as to establish the standard testing program.展开更多
Annual precipitation,evaporation,and calculated accumulation from reanalysis model outputs have been investigated for the Greenland Ice Sheet (GrIS),based on the common period of 1989-2001.The ERA-40 and ERA-interim r...Annual precipitation,evaporation,and calculated accumulation from reanalysis model outputs have been investigated for the Greenland Ice Sheet (GrIS),based on the common period of 1989-2001.The ERA-40 and ERA-interim reanalysis data showed better agreement with observations than do NCEP-1 and NCEP-2 reanalyses.Further,ERA-interim showed the closest spatial distribution of accumulation to the observation.Concerning temporal variations,ERA-interim showed the best correlation with precipitation observations at five synoptic stations,and the best correlation with in situ measurements of accumulation at nine ice core sites.The mean annual precipitation averaged over the whole GrIS from ERA-interim (363 mm yr 1) and mean annual accumulation (319 mm yr 1) are very close to the observations.The validation of accumulation calculated from reanalysis data against ice-core measurements suggests that further improvements to reanalysis models are needed.展开更多
As one of Qo S(Quality of Service) metrics, delay is critical important to delay sensitive applications, such as interactive video, network game and online surgery. In this paper, we exploit SDN(Software Defined Netwo...As one of Qo S(Quality of Service) metrics, delay is critical important to delay sensitive applications, such as interactive video, network game and online surgery. In this paper, we exploit SDN(Software Defined Networking) advantages to solve delay Qo S problem. Our work mainly focuses on SDN based queuing delay estimation with real traffic and end-to-end delay control. First, we propose a queuing estimation model and extended it for end-to-end delay of the whole path. It is proved to be feasible and accurate with experimental results in SDN environment. Second, in order to demonstrate the use of our proposed model, we also implement an end-to-end delay control application in SDN. It fulfills specific delay Qo S requirements by dynamically switching flows to a suitable queue based on estimation results and delay requirements.展开更多
A review of three-phase PWM converter topologies which do show a low complexity/high reliability and high efficiency and power density and are therefore of main interest for a future industrial application is presente...A review of three-phase PWM converter topologies which do show a low complexity/high reliability and high efficiency and power density and are therefore of main interest for a future industrial application is presented.A three-switch/level Boost-type PWM rectifier(VIENNA Rectifier),a Buck+Boost-type PWM rectifier with wide output voltage range and the AC/AC Sparse Matrix Converter concept are discussed in detail and topics to be treated in the course of further research are identified.Finally,it is shown how the aspects being relevant for the realization of highly compact converter systems could be integrated into education in the field.展开更多
The Action Group called‘Standardized methods across Permafrost Landscapes:from Arctic Soils to Hydrosystems’(SPLASH)is a community-driven effort aiming to provide a suite of standardized field strategies for samplin...The Action Group called‘Standardized methods across Permafrost Landscapes:from Arctic Soils to Hydrosystems’(SPLASH)is a community-driven effort aiming to provide a suite of standardized field strategies for sampling mineral and organic components in soils,sediments,and water across permafrost landscapes.This unified approach will allow data from different landscape interfaces,field locations and seasons to be shared and compared,thus improving our understanding of the processes occurring during lateral transport in circumpolar Arctic watersheds.展开更多
CEM43 thermal dose is a very common concept in thermal oncology.Thermal dose is the maximum amount of energy that can be transmitted during hyperthermia therapy conducted on temperature-sensitive tissue.Thermal dose i...CEM43 thermal dose is a very common concept in thermal oncology.Thermal dose is the maximum amount of energy that can be transmitted during hyperthermia therapy conducted on temperature-sensitive tissue.Thermal dose is also the maximum value of local energy accumulation in human bodies,which can lead to tissue injury and pain.Thermal dose can also decrease the finishing temperature and reduce the energy to the tolerable range.There are two functions of the individualized hyperthermia treatment plan:it determines the setting and location that can realize the best tumor hyperthermia therapy;at the same time,it can decrease the effect of hyperthermia therapy on healthy tissues.There are four steps in the treatment plan of hyperthermia therapy for tumors:the first step is to establish a three dimensional human body model and its corresponding an atomical structure that can be used in numerical algorithm via medical imaging resources;the second step is to determine the volume of the electromagnetic energy accumulation.Based on the peculiarity of frequency and materials,even full-wave electromagnetic wave or quasi-static technique can be used to determine the tissue distribution.Evaluation of the therapy can be conducted based on thermal dose and the corresponding tissue damage model;the third step is to use Arrhenius model to provide direct evaluation of tissues in the thermal ablation zone,solidification zone,as well as the necrotic area;the last step is the optimization of the treatment plan.展开更多
Cancer patients with advanced disease are characterized by intrinsic challenges in predicting drug response patterns,often leading to ineffective treatment.Current clinical practice for treatment decision-making is co...Cancer patients with advanced disease are characterized by intrinsic challenges in predicting drug response patterns,often leading to ineffective treatment.Current clinical practice for treatment decision-making is commonly based on primary or secondary tumour biopsies,yet when disease progression accelerates,tissue biopsies are not performed on a regular basis.It is in this context that liquid biopsies may offer a unique window to uncover key vulnerabilities,providing valuable information about previously underappreciated treatment opportunities.Here,we present MyCTC chip,a novel microfluidic device enabling the isolation,culture and drug susceptibility testing of cancer cells derived from liquid biopsies.Cancer cell capture is achieved through a label-free,antigen-agnostic enrichment method,and it is followed by cultivation in dedicated conditions,allowing on-chip expansion of captured cells.Upon growth,cancer cells are then transferred to drug screen chambers located within the same device,where multiple compounds can be tested simultaneously.We demonstrate MyCTC chip performance by means of spike-in experiments with patientderived breast circulating tumour cells,enabling>95%capture rates,as well as prospective processing of blood from breast cancer patients and ascites fluid from patients with ovarian,tubal and endometrial cancer,where sensitivity to specific chemotherapeutic agents was identified.Together,we provide evidence that MyCTC chip may be used to identify personalized drug response patterns in patients with advanced metastatic disease and with limited treatment opportunities.展开更多
First a report about present status of circulating fluidized bed reactors for coal and multi-fuel combustion in power plants is given. Thereafter the development potentials and research needs for further improvement o...First a report about present status of circulating fluidized bed reactors for coal and multi-fuel combustion in power plants is given. Thereafter the development potentials and research needs for further improvement of CFB com-bustors operating with finely grained bed materials are discussed and recommendations for direction of further research and development work are presented.展开更多
Driven by increasing global population and by growing demand for individual wealth,the consumption of energy and raw materials as well as the steadily growing CO_2 concentration in atmosphere pose great challenges to ...Driven by increasing global population and by growing demand for individual wealth,the consumption of energy and raw materials as well as the steadily growing CO_2 concentration in atmosphere pose great challenges to process engineering.This complex multi-scale discipline deals with the transformation of mass by energy to manifold products in different industrial fields under economical and ecological sustainable conditions.In growing circular economy,process engineering increasingly plays an important role in recovering valuable components from very diffuse material flows leaving the user stocks following widely variable time periods of use.As well it is engaged in thermal recovery of energy therefrom and in environmentally safe disposal of residual solid wastes whose recovery economically is not feasible.An efficient recovery of materials and energy following the laws of entropy is a must.A complex network of mass,energy,transportation and information flows has to be regarded with growing traded quantities of used goods even on global level.Important constraints in time,however,exist for a necessary realization of innovative new processes and communal mobility and industrial infrastructure on medium and large scale.Based on reasonable long term and highly reliable statistics from industrial organizations representing steel and paper industry,some limits and trends of possible developments in processing of those industries with long recycling experience will be discussed.展开更多
Dehydration of the subducting slab favors the melting of the surrounding mantle.Water content and melt evolution atop a spontaneously retreating subducting slab are reported in a three-dimensional(3-D) model.We find t...Dehydration of the subducting slab favors the melting of the surrounding mantle.Water content and melt evolution atop a spontaneously retreating subducting slab are reported in a three-dimensional(3-D) model.We find that fluids,including water and melts in the rocks,vary substantially along the trench,which cannot be found in two-dimensional(2-D) models.Their maxima along the subducting slab are mainly located at about 50 to 70 and 120 to 140 km.Volumetric melt production rate changes spatially and episodically atop the slab,which may reflect the intensity and variations of volcanoes.展开更多
Background:Dengue,an infectious tropical disease,has recently emerged as one of the most important mosquito-borne viral diseases in the world.We perform a retrospective analysis of the 2011 dengue fever epidemic in Pa...Background:Dengue,an infectious tropical disease,has recently emerged as one of the most important mosquito-borne viral diseases in the world.We perform a retrospective analysis of the 2011 dengue fever epidemic in Pakistan in order to assess the transmissibility of the disease.We obtain estimates of the basic reproduction number R0 from epidemic data using different methodologies applied to different epidemic models in order to evaluate the robustness of our estimate.Results:We first estimate model parameters by fitting a deterministic ODE vector-host model for the transmission dynamics of single-strain dengue to the epidemic data,using both a basic ordinary least squares(OLS)as well as a generalized least squares(GLS)scheme.Moreover,we perform the same analysis for a direct-transmission ODE model,thereby allowing us to compare our results across different models.In addition,we formulate a direct-transmission stochastic model for the transmission dynamics of dengue and obtain parameter estimates for the stochastic model using Markov chain Monte Carlo(MCMC)methods.In each of the cases we have considered,the estimate for the basic reproduction number R0 is initially greater than unity leading to an epidemic outbreak.However,control measures implemented several weeks after the initial outbreak successfully reduce R0 to less than unity,thus resulting in disease elimination.Furthermore,it is observed that there is strong agreement in our estimates for the pre-control value of R0,both across different methodologies as well across different models.However,there are also significant differences between our estimates for the post-control value of the basic reproduction number across the two different models.Conclusion:In conclusion,we have obtained robust estimates for the value of the basic reproduction number R0 associated with the 2011 dengue fever epidemic before the implementation of public health control measures.Furthermore,we have shown that there is close agreement between our estimates for the post-control value of R0 across the different methodologies.Nevertheless,there are also significant differences between the estimates for the post-control value of R0 across the two different models.展开更多
Energy-efficient electro-optic modulators are at the heart of short-reach optical interconnects,and silicon photonics is considered the leading technology for realizing such devices.However,the performance of all-sili...Energy-efficient electro-optic modulators are at the heart of short-reach optical interconnects,and silicon photonics is considered the leading technology for realizing such devices.However,the performance of all-silicon devices is limited by intrinsic material properties.In particular,the absence of linear electro-optic effects in silicon renders the integration of energy-efficient photonic–electronic interfaces challenging.Silicon–organic hybrid(SOH)integration can overcome these limitations by combining nanophotonic silicon waveguides with organic cladding materials,thereby offering the prospect of designing optical properties by molecular engineering.In this paper,we demonstrate an SOH Mach–Zehnder modulator with unprecedented efficiency:the 1-mm-long device consumes only 0.7 fJ bit^(-1) to generate a 12.5 Gbit s^(-1) data stream with a bit-error ratio below the threshold for hard-decision forward-error correction.This power consumption represents the lowest value demonstrated for a non-resonant Mach–Zehnder modulator in any material system.It is enabled by a novel class of organic electro-optic materials that are designed for high chromophore density and enhanced molecular orientation.The device features an electro-optic coefficient of r33<180 pm V^(-1) and can be operated at data rates of up to 40 Gbit s^(-1).展开更多
China has 46 377 glaciers with a total area of 59 425 km2, which accounts for 11%-14.5% of the total area of mountain glaciers in the world. As one of the largest mountain ranges in Central Asia and Northwest China, t...China has 46 377 glaciers with a total area of 59 425 km2, which accounts for 11%-14.5% of the total area of mountain glaciers in the world. As one of the largest mountain ranges in Central Asia and Northwest China, the Tianshan contains 15 935 gla-ciers with a total area of 15 416 km2. These glaciers are a vital source of water for more than 100 million people and for wildlife ecosystems in this vast arid and semi-arid land. Urumqi Glacier No. 1, the best monitored glacier in China, is located at the headwa-ters of the Urumqi River in eastern Tianshan and is within the core area of Central Asia.展开更多
文摘The tensile strength at the rock-concrete interface is one of the crucial factors controlling the failure mechanisms of structures,such as concrete gravity dams.Despite the critical importance of the failure mechanism and tensile strength of rock-concrete interfaces,understanding of these factors remains very limited.This study investigated the tensile strength and fracturing processes at rock-mortar interfaces subjected to direct and indirect tensile loadings.Digital image correlation(DIC)and acoustic emission(AE)techniques were used to monitor the failure mechanisms of specimens subjected to direct tension and indirect loading(Brazilian tests).The results indicated that the direct tensile strength of the rock-mortar specimens was lower than their indirect tensile strength,with a direct/indirect tensile strength ratio of 65%.DIC strain field data and moment tensor inversions(MTI)of AE events indicated that a significant number of shear microcracks occurred in the specimens subjected to the Brazilian test.The presence of these shear microcracks,which require more energy to break,resulted in a higher tensile strength during the Brazilian tests.In contrast,microcracks were predominantly tensile in specimens subjected to direct tension,leading to a lower tensile strength.Spatiotemporal monitoring of the cracking processes in the rock-mortar interfaces revealed that they show AE precursors before failure under the Brazilian test,whereas they show a minimal number of AE events before failure under direct tension.Due to different microcracking mechanisms,specimens tested under Brazilian tests showed lower roughness with flatter fracture surfaces than those tested under direct tension with jagged and rough fracture surfaces.The results of this study shed light on better understanding the micromechanics of damage in the rock-concrete interfaces for a safer design of engineering structures.
文摘We investigate the accuracy and robustness of moment tensor(MT)and stress inversion solutions derived from acoustic emissions(AEs)during the laboratory fracturing of prismatic Barre granite specimens.Pre-cut flaws in the specimens introduce a complex stress field,resulting in a spatial and temporal variation of focal mechanisms.Specifically,we consider two experimental setups:(1)where the rock is loaded in compression to generate primarily shear-type fractures and(2)where the material is loaded in indirect tension to generate predominantly tensile-type fractures.In each test,we first decompose AE moment tensors into double-couple(DC)and non-DC terms and then derive unambiguous normal and slip vectors using k-means clustering and an unstructured damped stress inversion algorithm.We explore temporal and spatial distributions of DC and non-DC events at different loading levels.The majority of the DC and the tensile non-DC events cluster around the pre-cut flaws,where macro-cracks later develop.Results of stress inversion are verified against the stress field from finite element(FE)modeling.A good agreement is found between the experimentally derived and numerically simulated stress orientations.To the best of the authors’knowledge,this work presents the first case where stress inversion methodologies are validated by numerical simulations at laboratory scale and under highly heterogeneous stress distributions.
文摘Attiéké is fermented cassava semolina steamed and consumed with proteins and vegetables. From Ivorian traditional origin, its popularity is increasing in Africa and production networks are developing. However, the growth of attiéké industry is still curbed by lack of technical skills of producers and irregular quality, depending on cassava variety, processing and inoculum. In the present study, a traditional inoculum and four cassava varieties (two improved local (IAC and Bonoua) and two improved sweet ones from Nigeria (Olekanga and TMS 4 (2) 1425)) were used for producing attiéké Ebrié. For the sensorial evaluation of prepared attiéké, qualitative sensory profiling was used. The sensory quality descriptors where quantitatively measured by a trained sensory panel. With this method the most important quality criteria of attiéké were judged. These quality criteria were selected with the aid of surveys on its production and consumption. The relationships between sensory attributes of the four attiéké prepared of the different cassava varieties and biochemical characteristics were studied. Sensory analysis revealed that the four attiéké were cream-colored products with sweet and/or sour tastes, made of cohesive and well-formed grains of different sizes, with an odor of fermentation specific to attiéké and showing a firm texture. The differences between sensory profiles of the four attiéké produced from four cassava varieties (12 months growth) concern only some descriptors of quality. Pearson correlation coefficients between physicochemical descriptors of quality showed that biochemical parameters may help predict organoleptic characteristics of attiéké Ebrié (pH-size of grains: r = 0.99;pH-acidity: r = ?0.92;acidity-rounded grains: r = ?0.98: starch-cohesion between grains: r = ?0.96;starch-sweet: r = ?0.95;starch-granulous: r = 0.97, total sugar-yellow color: r = 0.96;total sugar-aroma of attiéké: r = 0.96;reducing sugar-odor of attiéké: r = 0.95;cyanide-fibrous: r = 0.95).
文摘As a diagnostic method,magnetic resonance imaging(MRI)is not allowed to be used in patients with medical implants,including both active implants(such as cardiac defibrillators or deep brain stimulators)and passive implants(such as orthopedics implants and support).MRI imaging scanning can produce magnetic fields,which will produce concentrated electromagnetic induction on metal edges of the implants,such as electrodes.The magnetic field can also significantly increase the temperature of surrounding tissues.Besides,the currents and voltage produced by active implants when exposed to MRI scanning can lead to damage and malfunction of pulse generators.Therefore,patients with medical implants cannot receive MRI as a diagnostic method.This safety protocol prevents a large group of patients from receiving MRI diagnosis.This leads to the conclusion that the safety evaluation of implants under MRI environment requires the combination of accurate data analysis and experimental techniques so as to establish the standard testing program.
基金supported by the National Basic Research Program of China (Grant No. 2009CB421400)the National Science Foundation of China (Grant No. 40821092)
文摘Annual precipitation,evaporation,and calculated accumulation from reanalysis model outputs have been investigated for the Greenland Ice Sheet (GrIS),based on the common period of 1989-2001.The ERA-40 and ERA-interim reanalysis data showed better agreement with observations than do NCEP-1 and NCEP-2 reanalyses.Further,ERA-interim showed the closest spatial distribution of accumulation to the observation.Concerning temporal variations,ERA-interim showed the best correlation with precipitation observations at five synoptic stations,and the best correlation with in situ measurements of accumulation at nine ice core sites.The mean annual precipitation averaged over the whole GrIS from ERA-interim (363 mm yr 1) and mean annual accumulation (319 mm yr 1) are very close to the observations.The validation of accumulation calculated from reanalysis data against ice-core measurements suggests that further improvements to reanalysis models are needed.
基金supported by the project of 111 Intelligence Introduction for Innovation at Communication University of ChinaNSFC under grant No.61371191,No.61472389 and No.61201236ETH Zurich for the valuable discussion about H2020 MAMI project related to TCP modeling in this work
文摘As one of Qo S(Quality of Service) metrics, delay is critical important to delay sensitive applications, such as interactive video, network game and online surgery. In this paper, we exploit SDN(Software Defined Networking) advantages to solve delay Qo S problem. Our work mainly focuses on SDN based queuing delay estimation with real traffic and end-to-end delay control. First, we propose a queuing estimation model and extended it for end-to-end delay of the whole path. It is proved to be feasible and accurate with experimental results in SDN environment. Second, in order to demonstrate the use of our proposed model, we also implement an end-to-end delay control application in SDN. It fulfills specific delay Qo S requirements by dynamically switching flows to a suitable queue based on estimation results and delay requirements.
文摘A review of three-phase PWM converter topologies which do show a low complexity/high reliability and high efficiency and power density and are therefore of main interest for a future industrial application is presented.A three-switch/level Boost-type PWM rectifier(VIENNA Rectifier),a Buck+Boost-type PWM rectifier with wide output voltage range and the AC/AC Sparse Matrix Converter concept are discussed in detail and topics to be treated in the course of further research are identified.Finally,it is shown how the aspects being relevant for the realization of highly compact converter systems could be integrated into education in the field.
文摘The Action Group called‘Standardized methods across Permafrost Landscapes:from Arctic Soils to Hydrosystems’(SPLASH)is a community-driven effort aiming to provide a suite of standardized field strategies for sampling mineral and organic components in soils,sediments,and water across permafrost landscapes.This unified approach will allow data from different landscape interfaces,field locations and seasons to be shared and compared,thus improving our understanding of the processes occurring during lateral transport in circumpolar Arctic watersheds.
文摘CEM43 thermal dose is a very common concept in thermal oncology.Thermal dose is the maximum amount of energy that can be transmitted during hyperthermia therapy conducted on temperature-sensitive tissue.Thermal dose is also the maximum value of local energy accumulation in human bodies,which can lead to tissue injury and pain.Thermal dose can also decrease the finishing temperature and reduce the energy to the tolerable range.There are two functions of the individualized hyperthermia treatment plan:it determines the setting and location that can realize the best tumor hyperthermia therapy;at the same time,it can decrease the effect of hyperthermia therapy on healthy tissues.There are four steps in the treatment plan of hyperthermia therapy for tumors:the first step is to establish a three dimensional human body model and its corresponding an atomical structure that can be used in numerical algorithm via medical imaging resources;the second step is to determine the volume of the electromagnetic energy accumulation.Based on the peculiarity of frequency and materials,even full-wave electromagnetic wave or quasi-static technique can be used to determine the tissue distribution.Evaluation of the therapy can be conducted based on thermal dose and the corresponding tissue damage model;the third step is to use Arrhenius model to provide direct evaluation of tissues in the thermal ablation zone,solidification zone,as well as the necrotic area;the last step is the optimization of the treatment plan.
基金The NCCR RNA and disease funded by the Swiss National Science Foundation （SNF 51NF40_141735） for access to the Biomolecular NMR spectrometry platform at ETH ZUrich. This work was supported by an IIF Marie Curie fellowship to TI （no. 329029） and a European Research Council （ERC） advanced grant ＂Frontiers of RNAi-Ⅱ＂ to OV （no. 323071）.
基金supported by the European Research Council(101001652)the strategic focus area of Personalized Health and Related Technologies at ETH Zurich(PHRT-541)+5 种基金the Future and Emerging Technologies programme of the European Commission(801159-B2B)the Swiss National Science Foundation(310030_212183)the Swiss Cancer League(KLS-4834-08-2019)the Basel Cancer League(KLbB-4763-02-2019)and ETH Zürichthe strategic focus area of Personalized Health and Related Technologies at ETH Zurich(PHRT-541)the European Research Council(681587).
文摘Cancer patients with advanced disease are characterized by intrinsic challenges in predicting drug response patterns,often leading to ineffective treatment.Current clinical practice for treatment decision-making is commonly based on primary or secondary tumour biopsies,yet when disease progression accelerates,tissue biopsies are not performed on a regular basis.It is in this context that liquid biopsies may offer a unique window to uncover key vulnerabilities,providing valuable information about previously underappreciated treatment opportunities.Here,we present MyCTC chip,a novel microfluidic device enabling the isolation,culture and drug susceptibility testing of cancer cells derived from liquid biopsies.Cancer cell capture is achieved through a label-free,antigen-agnostic enrichment method,and it is followed by cultivation in dedicated conditions,allowing on-chip expansion of captured cells.Upon growth,cancer cells are then transferred to drug screen chambers located within the same device,where multiple compounds can be tested simultaneously.We demonstrate MyCTC chip performance by means of spike-in experiments with patientderived breast circulating tumour cells,enabling>95%capture rates,as well as prospective processing of blood from breast cancer patients and ascites fluid from patients with ovarian,tubal and endometrial cancer,where sensitivity to specific chemotherapeutic agents was identified.Together,we provide evidence that MyCTC chip may be used to identify personalized drug response patterns in patients with advanced metastatic disease and with limited treatment opportunities.
文摘First a report about present status of circulating fluidized bed reactors for coal and multi-fuel combustion in power plants is given. Thereafter the development potentials and research needs for further improvement of CFB com-bustors operating with finely grained bed materials are discussed and recommendations for direction of further research and development work are presented.
文摘Driven by increasing global population and by growing demand for individual wealth,the consumption of energy and raw materials as well as the steadily growing CO_2 concentration in atmosphere pose great challenges to process engineering.This complex multi-scale discipline deals with the transformation of mass by energy to manifold products in different industrial fields under economical and ecological sustainable conditions.In growing circular economy,process engineering increasingly plays an important role in recovering valuable components from very diffuse material flows leaving the user stocks following widely variable time periods of use.As well it is engaged in thermal recovery of energy therefrom and in environmentally safe disposal of residual solid wastes whose recovery economically is not feasible.An efficient recovery of materials and energy following the laws of entropy is a must.A complex network of mass,energy,transportation and information flows has to be regarded with growing traded quantities of used goods even on global level.Important constraints in time,however,exist for a necessary realization of innovative new processes and communal mobility and industrial infrastructure on medium and large scale.Based on reasonable long term and highly reliable statistics from industrial organizations representing steel and paper industry,some limits and trends of possible developments in processing of those industries with long recycling experience will be discussed.
基金supported by the SNF (Nos. 200021-116381/1,200020-126832/1)
文摘Dehydration of the subducting slab favors the melting of the surrounding mantle.Water content and melt evolution atop a spontaneously retreating subducting slab are reported in a three-dimensional(3-D) model.We find that fluids,including water and melts in the rocks,vary substantially along the trench,which cannot be found in two-dimensional(2-D) models.Their maxima along the subducting slab are mainly located at about 50 to 70 and 120 to 140 km.Volumetric melt production rate changes spatially and episodically atop the slab,which may reflect the intensity and variations of volcanoes.
文摘Background:Dengue,an infectious tropical disease,has recently emerged as one of the most important mosquito-borne viral diseases in the world.We perform a retrospective analysis of the 2011 dengue fever epidemic in Pakistan in order to assess the transmissibility of the disease.We obtain estimates of the basic reproduction number R0 from epidemic data using different methodologies applied to different epidemic models in order to evaluate the robustness of our estimate.Results:We first estimate model parameters by fitting a deterministic ODE vector-host model for the transmission dynamics of single-strain dengue to the epidemic data,using both a basic ordinary least squares(OLS)as well as a generalized least squares(GLS)scheme.Moreover,we perform the same analysis for a direct-transmission ODE model,thereby allowing us to compare our results across different models.In addition,we formulate a direct-transmission stochastic model for the transmission dynamics of dengue and obtain parameter estimates for the stochastic model using Markov chain Monte Carlo(MCMC)methods.In each of the cases we have considered,the estimate for the basic reproduction number R0 is initially greater than unity leading to an epidemic outbreak.However,control measures implemented several weeks after the initial outbreak successfully reduce R0 to less than unity,thus resulting in disease elimination.Furthermore,it is observed that there is strong agreement in our estimates for the pre-control value of R0,both across different methodologies as well across different models.However,there are also significant differences between our estimates for the post-control value of the basic reproduction number across the two different models.Conclusion:In conclusion,we have obtained robust estimates for the value of the basic reproduction number R0 associated with the 2011 dengue fever epidemic before the implementation of public health control measures.Furthermore,we have shown that there is close agreement between our estimates for the post-control value of R0 across the different methodologies.Nevertheless,there are also significant differences between the estimates for the post-control value of R0 across the two different models.
基金This work was supported by the European Research Council(ERC Starting Grant‘EnTeraPIC’,number 280145)by the Alfried Krupp von Bohlen und Halbach Foundation,and by the Initiative and Networking Fund of the Helmholtz Association+7 种基金We further acknowledge support by the DFG Center for Functional Nanostructuresby the Karlsruhe International Research School on Teratronics,by the Karlsruhe School of Optics and Photonicsby the Karlsruhe Nano-Micro Facility,by the DFG Major Research Instrumentation Programmeby the EU-FP7 projects PHOXTROT and BigPIPESby Deutsche Forschungsgemeinschaftby the Open Access Publishing Fund of Karlsruhe Institute of TechnologyFurther financial support was obtained from the National Science Foundation(DMR-0905686,DMR-0120967)the Air Force Office of Scientific Research(FA9550-09-1-0682)
文摘Energy-efficient electro-optic modulators are at the heart of short-reach optical interconnects,and silicon photonics is considered the leading technology for realizing such devices.However,the performance of all-silicon devices is limited by intrinsic material properties.In particular,the absence of linear electro-optic effects in silicon renders the integration of energy-efficient photonic–electronic interfaces challenging.Silicon–organic hybrid(SOH)integration can overcome these limitations by combining nanophotonic silicon waveguides with organic cladding materials,thereby offering the prospect of designing optical properties by molecular engineering.In this paper,we demonstrate an SOH Mach–Zehnder modulator with unprecedented efficiency:the 1-mm-long device consumes only 0.7 fJ bit^(-1) to generate a 12.5 Gbit s^(-1) data stream with a bit-error ratio below the threshold for hard-decision forward-error correction.This power consumption represents the lowest value demonstrated for a non-resonant Mach–Zehnder modulator in any material system.It is enabled by a novel class of organic electro-optic materials that are designed for high chromophore density and enhanced molecular orientation.The device features an electro-optic coefficient of r33<180 pm V^(-1) and can be operated at data rates of up to 40 Gbit s^(-1).
基金supports from the National Natural Science Foundation of China (Nos. 40631001, 91025012) are greatly appreciated
文摘China has 46 377 glaciers with a total area of 59 425 km2, which accounts for 11%-14.5% of the total area of mountain glaciers in the world. As one of the largest mountain ranges in Central Asia and Northwest China, the Tianshan contains 15 935 gla-ciers with a total area of 15 416 km2. These glaciers are a vital source of water for more than 100 million people and for wildlife ecosystems in this vast arid and semi-arid land. Urumqi Glacier No. 1, the best monitored glacier in China, is located at the headwa-ters of the Urumqi River in eastern Tianshan and is within the core area of Central Asia.
