In this paper, we investigate the properties of an alternative material for use in marine engineering, namely a rigid and light sandwich-structured composite made of expanded polystyrene and fiberglass. Not only does ...In this paper, we investigate the properties of an alternative material for use in marine engineering, namely a rigid and light sandwich-structured composite made of expanded polystyrene and fiberglass. Not only does this material have an improved section modulus, but it is also inexpensive, light, easy to manipulate, and commercially available in various sizes. Using a computer program based on the finite element method, we calculated the hogging and sagging stresses and strains acting on a prismatic boat model composed of this material, and determined the minimum sizes and maximum permissible stresses to avoid deformation. Finally, we calculated the structural weight of the resulting vessel for comparison with another structure of comparable dimensions constructed from the commonly used core material Divinycell.展开更多
Objective:Bone metastasis occurs in up to 90%of men with advanced prostate cancer and leads to fractures,severe pain and therapy-resistance.Bone metastases induce a spectrum of types of bone lesions which can respond ...Objective:Bone metastasis occurs in up to 90%of men with advanced prostate cancer and leads to fractures,severe pain and therapy-resistance.Bone metastases induce a spectrum of types of bone lesions which can respond differently to therapy even within individual prostate cancer patients.Thus,the special environment of the bone makes the disease more complicated and incurable.A model in which bone lesions are reproducibly induced that mirrors the complexity seen in patients would be invaluable for pre-clinical testing of novel treatments.The microstructural changes in the femurs of mice implanted with PCSD1,a new patient-derived xenograft from a surgical prostate cancer bone metastasis specimen,were determined.Methods:Quantitative micro-computed tomography(micro-CT)and histological analyses were performed to evaluate the effects of direct injection of PCSD1 cells or media alone(Control)into the right femurs of Rag2/gc/male mice.Results:Bone lesions formed only in femurs of mice injected with PCSD1 cells.Bone volume(BV)was significantly decreased at the proximal and distal ends of the femurs(p<0.01)whereas BV(p<0.05)and bone shaft diameter(p<0.01)were significantly increased along the femur shaft.Conclusion:PCSD1 cells reproducibly induced bone loss leading to osteolytic lesions at the ends of the femur,and,in contrast,induced aberrant bone formation leading to osteoblastic lesions along the femur shaft.Therefore,the interaction of PCSD1 cells with different bone region-specific microenvironments specified the type of bone lesion.Our approach can be used to determine if different bone regions support more therapy resistant tumor growth,thus,requiring novel treatments.展开更多
The incorporation of interface passivation structures in ultrathin Cu(In,Ga)Se_(2)based solar cells is shown.The fabrication used an industry scalable lithography technique—nanoimprint lithography(NIL)—for a 15×...The incorporation of interface passivation structures in ultrathin Cu(In,Ga)Se_(2)based solar cells is shown.The fabrication used an industry scalable lithography technique—nanoimprint lithography(NIL)—for a 15×15 cm^(2)dielectric layer patterning.Devices with a NIL nanopatterned dielectric layer are benchmarked against electron-beam lithography(EBL)patterning,using rigid substrates.The NIL patterned device shows similar performance to the EBL patterned device.The impact of the lithographic processes in the rigid solar cells’performance were evaluated via X-ray Photoelectron Spectroscopy and through a Solar Cell Capacitance Simulator.The device on stainless-steel showed a slightly lower performance than the rigid approach,due to additional challenges of processing steel substrates,even though scanning transmission electron microscopy did not show clear evidence of impurity diffusion.Notwithstanding,time-resolved photoluminescence results strongly suggested elemental diffusion from the flexible substrate.Nevertheless,bending tests on the stainless-steel device demonstrated the mechanical stability of the CIGS-based device.展开更多
High compression ratio,high decoding performance,and progressive data transmission are the most important require-ments of vector data compression algorithms for WebGIS.To meet these requirements,we present a new comp...High compression ratio,high decoding performance,and progressive data transmission are the most important require-ments of vector data compression algorithms for WebGIS.To meet these requirements,we present a new compression approach.This paper begins with the generation of multiscale data by converting float coordinates to integer coordinates.It is proved that the distance between the converted point and the original point on screen is within 2 pixels,and therefore,our approach is suitable for the visualization of vector data on the client side.Integer coordinates are passed to an Integer Wavelet Transformer,and the high-frequency coefficients produced by the transformer are encoded by Canonical Huffman codes.The experimental results on river data and road data demonstrate the effectiveness of the proposed approach:compression ratio can reach 10% for river data and 20% for road data,respectively.We conclude that more attention needs be paid to correlation between curves that contain a few points.展开更多
Interposers with through-silicon vias(TSVs)play a key role in the three-dimensional integration and packaging of integrated circuits and microelectromechanical systems.In the current practice of fabricating interposer...Interposers with through-silicon vias(TSVs)play a key role in the three-dimensional integration and packaging of integrated circuits and microelectromechanical systems.In the current practice of fabricating interposers,solder balls are placed next to the vias;however,this approach requires a large foot print for the input/output(I/O)connections.Therefore,in this study,we investigate the possibility of placing the solder balls directly on top of the vias,thereby enabling a smaller pitch between the solder balls and an increased density of the I/O connections.To reach this goal,inkjet printing(that is,piezo and super inkjet)was used to successfully fill and planarize hollow metal TSVs with a dielectric polymer.The under bump metallization(UBM)pads were also successfully printed with inkjet technology on top of the polymer-filled vias,using either Ag or Au inks.The reliability of the TSV interposers was investigated by a temperature cycling stress test(−40℃ to+125℃).The stress test showed no impact on DC resistance of the TSVs;however,shrinkage and delamination of the polymer was observed,along with some micro-cracks in the UBM pads.For proof of concept,SnAgCu-based solder balls were jetted on the UBM pads.展开更多
Graphene’s unparalleled strength,chemical stability,ultimate surface-to-volume ratio and excellent electronic properties make it an ideal candidate as a material for membranes in micro-and nanoelectromechanical syste...Graphene’s unparalleled strength,chemical stability,ultimate surface-to-volume ratio and excellent electronic properties make it an ideal candidate as a material for membranes in micro-and nanoelectromechanical systems(MEMS and NEMS).However,the integration of graphene into MEMS or NEMS devices and suspended structures such as proof masses on graphene membranes raises several technological challenges,including collapse and rupture of the graphene.We have developed a robust route for realizing membranes made of double-layer CVD graphene and suspending large silicon proof masses on membranes with high yields.We have demonstrated the manufacture of square graphene membranes with side lengths from 7µm to 110µm,and suspended proof masses consisting of solid silicon cubes that are from 5µm×5µm×16.4µm to 100µm×100µm×16.4µm in size.Our approach is compatible with wafer-scale MEMS and semiconductor manufacturing technologies,and the manufacturing yields of the graphene membranes with suspended proof masses were>90%,with>70%of the graphene membranes having>90%graphene area without visible defects.The measured resonance frequencies of the realized structures ranged from tens to hundreds of kHz,with quality factors ranging from 63 to 148.The graphene membranes with suspended proof masses were extremely robust,and were able to withstand indentation forces from an atomic force microscope(AFM)tip of up to~7000nN.The proposed approach for the reliable and large-scale manufacture of graphene membranes with suspended proof masses will enable the development and study of innovative NEMS devices with new functionalities and improved performances.展开更多
Fungal endophytes are receiving increasing attention as resources to improve crop production and ecosystem management.However,the biology and ecological significance of these symbionts remains poorly understood,due to...Fungal endophytes are receiving increasing attention as resources to improve crop production and ecosystem management.However,the biology and ecological significance of these symbionts remains poorly understood,due to a lack of model systems for more efficient research.In this work,we have analyzed the culturable endophytic mycobiota associated,in the wild,with leaves and siliques of the model plant A.thaliana.We have studied the effect of biotic and abiotic factors in the frequency of fungal endophytes in plant specimens,and in the species composition of the endophytic community.Our results indicate that the frequency of Arabidopsis plants hosting endophytes depends on the time of the year and the phenological stage of the plant,and that the probability of endophyte colonization increases as the life cycle of the plant progresses.The diversity of the endophytic assemblages of natural A.thaliana populations was high,and precipitation and temperature were the two main factors determining the diversity and species composition of the communities.We propose A.thaliana and its endophytes as a model system for an integral approach to the principles governing the endophytic lifestyle,taking advantage of the molecular tools and the abundant knowledge accessible from the host plant.展开更多
文摘In this paper, we investigate the properties of an alternative material for use in marine engineering, namely a rigid and light sandwich-structured composite made of expanded polystyrene and fiberglass. Not only does this material have an improved section modulus, but it is also inexpensive, light, easy to manipulate, and commercially available in various sizes. Using a computer program based on the finite element method, we calculated the hogging and sagging stresses and strains acting on a prismatic boat model composed of this material, and determined the minimum sizes and maximum permissible stresses to avoid deformation. Finally, we calculated the structural weight of the resulting vessel for comparison with another structure of comparable dimensions constructed from the commonly used core material Divinycell.
基金We are grateful for the funding support for this work from the Leo and Anne Albert Charitable Foundation and the Phi Beta Psi Sorority.We deeply appreciate the invaluable contributions of Dr.Nissi Varki,Director,and Laarni Gapuz,Manager,Moores Cancer Center Histology Core.
文摘Objective:Bone metastasis occurs in up to 90%of men with advanced prostate cancer and leads to fractures,severe pain and therapy-resistance.Bone metastases induce a spectrum of types of bone lesions which can respond differently to therapy even within individual prostate cancer patients.Thus,the special environment of the bone makes the disease more complicated and incurable.A model in which bone lesions are reproducibly induced that mirrors the complexity seen in patients would be invaluable for pre-clinical testing of novel treatments.The microstructural changes in the femurs of mice implanted with PCSD1,a new patient-derived xenograft from a surgical prostate cancer bone metastasis specimen,were determined.Methods:Quantitative micro-computed tomography(micro-CT)and histological analyses were performed to evaluate the effects of direct injection of PCSD1 cells or media alone(Control)into the right femurs of Rag2/gc/male mice.Results:Bone lesions formed only in femurs of mice injected with PCSD1 cells.Bone volume(BV)was significantly decreased at the proximal and distal ends of the femurs(p<0.01)whereas BV(p<0.05)and bone shaft diameter(p<0.01)were significantly increased along the femur shaft.Conclusion:PCSD1 cells reproducibly induced bone loss leading to osteolytic lesions at the ends of the femur,and,in contrast,induced aberrant bone formation leading to osteoblastic lesions along the femur shaft.Therefore,the interaction of PCSD1 cells with different bone region-specific microenvironments specified the type of bone lesion.Our approach can be used to determine if different bone regions support more therapy resistant tumor growth,thus,requiring novel treatments.
基金InovSolarCells(PTDC/FISMAC/29696/2017)co-funded by FCT and the ERDF through COMPETE2020And by the European Union’s Horizon 2020 research and innovation programme under the grants agreements N°.720887(ARCIGS-M project)+2 种基金grand agreement N°.715027(Uniting PV)P.M.P.S.and P.A.F.would like to acknowledge FCT for the support of the project FCT UIDB/04730/2020This work was developed within the scope of the project i3N,UIDB/50025/2020&UIDP/50025/2020,financed by national funds through the FCT/MEC.
文摘The incorporation of interface passivation structures in ultrathin Cu(In,Ga)Se_(2)based solar cells is shown.The fabrication used an industry scalable lithography technique—nanoimprint lithography(NIL)—for a 15×15 cm^(2)dielectric layer patterning.Devices with a NIL nanopatterned dielectric layer are benchmarked against electron-beam lithography(EBL)patterning,using rigid substrates.The NIL patterned device shows similar performance to the EBL patterned device.The impact of the lithographic processes in the rigid solar cells’performance were evaluated via X-ray Photoelectron Spectroscopy and through a Solar Cell Capacitance Simulator.The device on stainless-steel showed a slightly lower performance than the rigid approach,due to additional challenges of processing steel substrates,even though scanning transmission electron microscopy did not show clear evidence of impurity diffusion.Notwithstanding,time-resolved photoluminescence results strongly suggested elemental diffusion from the flexible substrate.Nevertheless,bending tests on the stainless-steel device demonstrated the mechanical stability of the CIGS-based device.
基金Supported by the National High-tech R&D Program of China(NO.2007AA120501)
文摘High compression ratio,high decoding performance,and progressive data transmission are the most important require-ments of vector data compression algorithms for WebGIS.To meet these requirements,we present a new compression approach.This paper begins with the generation of multiscale data by converting float coordinates to integer coordinates.It is proved that the distance between the converted point and the original point on screen is within 2 pixels,and therefore,our approach is suitable for the visualization of vector data on the client side.Integer coordinates are passed to an Integer Wavelet Transformer,and the high-frequency coefficients produced by the transformer are encoded by Canonical Huffman codes.The experimental results on river data and road data demonstrate the effectiveness of the proposed approach:compression ratio can reach 10% for river data and 20% for road data,respectively.We conclude that more attention needs be paid to correlation between curves that contain a few points.
基金This work is supported by ENIAC-JU Project Prominent Grant No 324189 and Tekes Grant No.40336/12 and Vinnova Grants Nos.2012-04301,2012-04287,and 2012-04314MM is supported by the Academy of Finland Grant Nos.288945 and 294119The work of Silex and KTH was funded in part through an Industrial Ph.D.grant from the Swedish Foundation for Strategic Research(SSF),Grant No.ID14-0033.
文摘Interposers with through-silicon vias(TSVs)play a key role in the three-dimensional integration and packaging of integrated circuits and microelectromechanical systems.In the current practice of fabricating interposers,solder balls are placed next to the vias;however,this approach requires a large foot print for the input/output(I/O)connections.Therefore,in this study,we investigate the possibility of placing the solder balls directly on top of the vias,thereby enabling a smaller pitch between the solder balls and an increased density of the I/O connections.To reach this goal,inkjet printing(that is,piezo and super inkjet)was used to successfully fill and planarize hollow metal TSVs with a dielectric polymer.The under bump metallization(UBM)pads were also successfully printed with inkjet technology on top of the polymer-filled vias,using either Ag or Au inks.The reliability of the TSV interposers was investigated by a temperature cycling stress test(−40℃ to+125℃).The stress test showed no impact on DC resistance of the TSVs;however,shrinkage and delamination of the polymer was observed,along with some micro-cracks in the UBM pads.For proof of concept,SnAgCu-based solder balls were jetted on the UBM pads.
基金We acknowledge support through a scholarship from China Scholarship Council,the Starting Grants M&M’s(277879)and InteGraDe(307311)as well as Graphene Flagship(785219)from the European Research Council,the Swedish Research Council(GEMS,2015-05112)+2 种基金the German Federal Ministry for Education and Research(NanoGraM,BMBF,03XP0006C)the German Research Foundation(DFG,LE 2440/1-2)the German Federal Ministry for Education and Research(BMBF:NanoGraM,03XP0006 and GIMMIK,03XP0210)。
文摘Graphene’s unparalleled strength,chemical stability,ultimate surface-to-volume ratio and excellent electronic properties make it an ideal candidate as a material for membranes in micro-and nanoelectromechanical systems(MEMS and NEMS).However,the integration of graphene into MEMS or NEMS devices and suspended structures such as proof masses on graphene membranes raises several technological challenges,including collapse and rupture of the graphene.We have developed a robust route for realizing membranes made of double-layer CVD graphene and suspending large silicon proof masses on membranes with high yields.We have demonstrated the manufacture of square graphene membranes with side lengths from 7µm to 110µm,and suspended proof masses consisting of solid silicon cubes that are from 5µm×5µm×16.4µm to 100µm×100µm×16.4µm in size.Our approach is compatible with wafer-scale MEMS and semiconductor manufacturing technologies,and the manufacturing yields of the graphene membranes with suspended proof masses were>90%,with>70%of the graphene membranes having>90%graphene area without visible defects.The measured resonance frequencies of the realized structures ranged from tens to hundreds of kHz,with quality factors ranging from 63 to 148.The graphene membranes with suspended proof masses were extremely robust,and were able to withstand indentation forces from an atomic force microscope(AFM)tip of up to~7000nN.The proposed approach for the reliable and large-scale manufacture of graphene membranes with suspended proof masses will enable the development and study of innovative NEMS devices with new functionalities and improved performances.
基金funded by grants CAM CCG07-UPM/GEN-1899 of DGUI of Comunidad de Madrid and UPM and AGL2008-00818 of Ministerio de Educación y Ciencia of the Spanish Government to Soledad Sacristán.
文摘Fungal endophytes are receiving increasing attention as resources to improve crop production and ecosystem management.However,the biology and ecological significance of these symbionts remains poorly understood,due to a lack of model systems for more efficient research.In this work,we have analyzed the culturable endophytic mycobiota associated,in the wild,with leaves and siliques of the model plant A.thaliana.We have studied the effect of biotic and abiotic factors in the frequency of fungal endophytes in plant specimens,and in the species composition of the endophytic community.Our results indicate that the frequency of Arabidopsis plants hosting endophytes depends on the time of the year and the phenological stage of the plant,and that the probability of endophyte colonization increases as the life cycle of the plant progresses.The diversity of the endophytic assemblages of natural A.thaliana populations was high,and precipitation and temperature were the two main factors determining the diversity and species composition of the communities.We propose A.thaliana and its endophytes as a model system for an integral approach to the principles governing the endophytic lifestyle,taking advantage of the molecular tools and the abundant knowledge accessible from the host plant.