Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the ...Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). However, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimization of the macroscopic holes silk^(+) tNGC approach containing macroscopic holes might result in improved grafting technology suitable for future clinical use.展开更多
On-time mapping dynamics of crop area,yield,and production is important for global food security.Such information,however,is often not available.Here,we used satellite information,a spectral-phenology integration appr...On-time mapping dynamics of crop area,yield,and production is important for global food security.Such information,however,is often not available.Here,we used satellite information,a spectral-phenology integration approach for mapping crop area,and a machine learning model for predicting yield in the war-stricken Ukraine.We found that in Ukraine crop area and production declined in 2022 relative to 2017–2021 and 2021 for wintertriticeae crops,which was invaded before the cropping season in February of that year.At the same time,crop area and production for rapeseed increased in Ukraine,with yields consistently lower by 6.5%relative to 2021.The low precipitation and the Russian-Ukrainian conflict-related factors contributed to such yield variations by-1.3%and-0.9%for winter-triticeae crops and-4.2%and-0.5%for rapeseed in 2022.We demonstrate a robust framework for monitoring country-wide crop production dynamics in near real-time,serving as an early-foodsecurity-warning system.展开更多
Imaging technologies based on chemiluminescence(CL)and bioluminescence(BL)have seen a tremendous growth in the past decade due to their extensive contributions to biochemical analysis and biomedical science.CL and BL ...Imaging technologies based on chemiluminescence(CL)and bioluminescence(BL)have seen a tremendous growth in the past decade due to their extensive contributions to biochemical analysis and biomedical science.CL and BL imaging technologies have many advantages over commonly used imaging techniques(such as fluorescence and electrochemical systems).CL and BL proceed without an external light source,thus avoiding photobleaching,high interference of background signal,and autofluorescence.Furthermore,CL and BL analytical techniques are characterized by their low detection limit,high selectivity,short assay time,and simple instrumentation.Recently,CL-based imaging technology has been applied successfully for the determination and in vivo imaging of several significant analytes.Meanwhile,an innovative BL imaging technology has been established for the noninvasive real-time tracking of different biomolecules relying on the interaction between luciferase and its substrate.In the current review,we discuss the recent applications of CL and BL imaging approaches over the past five years.Finally,we also discuss the current state of progress and the prospects for CL and BL imaging systems.展开更多
基金supported by the Lorenz B?hler Fonds,#2/19 (obtained by the Neuroregeneration Group,Ludwig Boltzmann Institute for Traumatology)the City of Vienna project ImmunTissue,MA23#30-11 (obtained by the Department Life Science Engineering,University of Applied Sciences Technikum Wien)。
文摘Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). However, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimization of the macroscopic holes silk^(+) tNGC approach containing macroscopic holes might result in improved grafting technology suitable for future clinical use.
基金supported by the National Natural Science Foundation of China(Grant No.42061144003).
文摘On-time mapping dynamics of crop area,yield,and production is important for global food security.Such information,however,is often not available.Here,we used satellite information,a spectral-phenology integration approach for mapping crop area,and a machine learning model for predicting yield in the war-stricken Ukraine.We found that in Ukraine crop area and production declined in 2022 relative to 2017–2021 and 2021 for wintertriticeae crops,which was invaded before the cropping season in February of that year.At the same time,crop area and production for rapeseed increased in Ukraine,with yields consistently lower by 6.5%relative to 2021.The low precipitation and the Russian-Ukrainian conflict-related factors contributed to such yield variations by-1.3%and-0.9%for winter-triticeae crops and-4.2%and-0.5%for rapeseed in 2022.We demonstrate a robust framework for monitoring country-wide crop production dynamics in near real-time,serving as an early-foodsecurity-warning system.
基金support by National Natural Science Foundation of China(22174136,22004116,and 21874126)Department of Science and Technology of Jilin Province(L202234)+3 种基金Chinese Academy of Sciences(CAS),Iran National Science Foundation(CAS-VPST Silk Road Science Fund 2021 Nos.GJHZ202125 and INSF99008701)the Ministry of Education and Science of Ukraine(M/109-2019,M/97-2020,0122U001533)National Research Foundation of Ukraine(2020.02/0390)the Ministry of Science and Technology of the People’s Republic of China(CU03-02).
文摘Imaging technologies based on chemiluminescence(CL)and bioluminescence(BL)have seen a tremendous growth in the past decade due to their extensive contributions to biochemical analysis and biomedical science.CL and BL imaging technologies have many advantages over commonly used imaging techniques(such as fluorescence and electrochemical systems).CL and BL proceed without an external light source,thus avoiding photobleaching,high interference of background signal,and autofluorescence.Furthermore,CL and BL analytical techniques are characterized by their low detection limit,high selectivity,short assay time,and simple instrumentation.Recently,CL-based imaging technology has been applied successfully for the determination and in vivo imaging of several significant analytes.Meanwhile,an innovative BL imaging technology has been established for the noninvasive real-time tracking of different biomolecules relying on the interaction between luciferase and its substrate.In the current review,we discuss the recent applications of CL and BL imaging approaches over the past five years.Finally,we also discuss the current state of progress and the prospects for CL and BL imaging systems.
