On March 1 and 5, 1982, experiments in television photography instrumented by the landers VENERA-13 and 14 returned panoramas of the Venus surface at the landing site. Over the past 31 years, no similar missions have ...On March 1 and 5, 1982, experiments in television photography instrumented by the landers VENERA-13 and 14 returned panoramas of the Venus surface at the landing site. Over the past 31 years, no similar missions have been sent to Venus. In connection with the renewed interest in what was occurring during the experiment and to the discovery of manifestations of possible life revealed on some of the pictures, the panoramas were re-examined.?Analysis of treated once again VENERA-14 panoramic images revealed a?“snake”?object about 40 cm in size possessing apparent terramorphic features. The snake’s body stands out with its honeycomb, spotty surface against the stone plates close by. The “snake”?can be included into the list of the most significant findings of the hypothetical Venusian fauna. Apart from that, of interest is a?“dove”?object, although details of its structure cannot be discerned. The snake’s body show slow movements, which is another evidence of the Venusian fauna’s very slow style of activity, which appears to be associated with its energy constraints, and that is more likely, with the properties of its internal medium. The terramorphic features of the fauna, if they are confirmed, may point out outstandingly important and yet undiscovered general laws of the animated nature.展开更多
BACKGROUND: No retrievable and repositionable second generation transcatheter aortic valve is available in China. Here, we report the first-in-man implantation of the retrievable and repositionable VenusA-Plus valve. ...BACKGROUND: No retrievable and repositionable second generation transcatheter aortic valve is available in China. Here, we report the first-in-man implantation of the retrievable and repositionable VenusA-Plus valve. METHODS: A 76-year-old patient with symptomatic severe aortic stenosis and high surgical risk(STS 13.8%) was recommended for transcatheter aortic valve replacement(TAVR) by heart valve team. Type 0 bicuspid aortic valve with asymmetric calcification was identified by dual source computed tomography, and the unfavorable anatomies increased the possibility of malposition and paravalvular leakage during TAVR. Therefore, we used the retrievable and repositionable Venus APlus valve for the patient.RESULTS: Transfemoral TAVR was performed under local anesthesia with sedation, and a 26-mm VenusA-Plus valve was successfully implanted. No transvalvular pressure gradient and trace paravalvular leakage were found. CONCLUSION: The successful first-in-man implantation indicates the retrievable and repositionable Venus A-Plus valve is feasible in complicated TAVR cases such as bicuspid aortic valve.展开更多
With Venus Express magnetic field measurements at 32 Hz from 2006 to 2012, we investigate statistically the magnetic fluctuations in the near-Venusian space. The global spatial distribution of their spectral scaling f...With Venus Express magnetic field measurements at 32 Hz from 2006 to 2012, we investigate statistically the magnetic fluctuations in the near-Venusian space. The global spatial distribution of their spectral scaling features is presented in MHD and kinetic regimes. It can be observed that turbulence is a common phenomenon in the solar wind in both regimes. The solar wind MHD turbulence is modified at the Venusian bow shock;MHD turbulence is absent in the Venusian magnetosheath but present at the magnetosheath boundary layer. Pre-existing kinetic turbulence from the far upstream solar wind is modified in the near solar wind region, while kinetic turbulence can be extensively observed throughout the Venusian magnetosheath and in some regions of the induced magnetosphere. Our results reveal that, in the near-Venusian space, energy cascade can be developed at the boundary between magnetosheath and wake, and the turbulence-related dissipation of magnetic energy occurs extensively in the magnetosheath and the induced magnetosphere.展开更多
Venusian coronae are large(60-2600 km diameter)tectono-magmatic features characterized by quasi-circular graben-fissure systems and topographic features such as a central dome,central depression,circular rim or circular
The Pre-Raphaelite painter Edward Burne-Jones(1833-1898)conceived the subject of The Mirror of Venus between 1865 and 1867.He painted two versions:a small version in gouache and oil and a larger version in oil on canv...The Pre-Raphaelite painter Edward Burne-Jones(1833-1898)conceived the subject of The Mirror of Venus between 1865 and 1867.He painted two versions:a small version in gouache and oil and a larger version in oil on canvas.In composing this subject Burne-Jones was inspired by the poetic and chromatic description of a lyrical stanza on“The Hill of Venus”in the long epic poem Earthly Paradise,written by his close friend and collaborator William Morris.1 This study comprises three parts:Burne-Jones’s history of the paintings,his iconographical sources,and an iconological interpretation of The Mirror of Venus.展开更多
The Venusian dayside ionosphere, similar to other planetary ionospheres, is produced primarily by ionization of its neutral upper atmosphere due to solar extreme ultraviolet (EUV) radiation. It has become clear that t...The Venusian dayside ionosphere, similar to other planetary ionospheres, is produced primarily by ionization of its neutral upper atmosphere due to solar extreme ultraviolet (EUV) radiation. It has become clear that the expansion of the ionosphere may be strongly controlled by the EUV level, as exhibited in data collected by the Pioneer Venus Orbiter (PVO) during one solar cycle (1978 1992). However, the EUV-dependence of the Venusian dayside ionopause altitude, which defines the outer boundary of the ionosphere, remains obscure because the PVO crossed the dayside ionopause only during the solar maximum;its periapsis lifted too high during the solar minimum. Recently, during the period 2006 2014, which included the longest and quietest solar minimum of the past several decades, Venus Express (VEX) provided measurements of the photoelectron boundary (PEB) over the northern high-latitude region. Since the photoelectron boundary is closely related to the ionopause, we have an opportunity to analyze the EUV effect on the dayside ionopause by combining PVO and VEX observations. We have evaluated and then reduced the orbit bias effect in data from both PVO and VEX, and then used the results to derive a relationship between solar EUV level and the dayside ionopause altitude. We find that the dayside ionopause altitude increases as the solar EUV level increases, which is consistent with theoretical expectations.展开更多
This paper is devoted to the development and testing of the optimal procedures for retrieving biophysical crop variables by exploiting the spectral information of current multispectral optical satellite Sentinel-2 and...This paper is devoted to the development and testing of the optimal procedures for retrieving biophysical crop variables by exploiting the spectral information of current multispectral optical satellite Sentinel-2 and Venus and in view of the advent of the new Sino-EU hyperspectral satellite(e.g.,PRISMA,EnMAP,and GF-5).Two different methodologies devoted to the estimation of biophysical crop variables Leaf area index(LAI)and Leaf chlorophyll content(Cab)were evaluated:non-kernel-based and kernel-based Machine Learning Regression Algorithms(MLRA);Sentinel-2 and Venus data comparison for the analysis of the durum wheat-growing season.Results show that for Sentinel-2 data,Gaussian Process Regression(GPR)was the best performing algorithm for both LAI(R 2=0.89 and RMSE=0.59)and Cab(R 2=0.70 and RMSE=8.31).Whereas,for PRISMA simulated data the Kernel Ridge Regression(KRR)was the best performing algorithm among all the other MLRA(R 2=0.91 and RMSE=0.51)for LAI and(R 2=0.83 and RMSE=6.09)for Cab,respectively.Results of Sentinel-2 and Venus data for durum wheat-growing season were consistent with ground truth data and confirm also that SWIR bands,which are used as tie-points in the PROSAIL inversion,are extremely useful for an accurate retrieving of crop biophysical parameters.展开更多
The Beta-Atla-Themis(BAT)region on Venus is characterized by large volcanic rises,major rift zones(chasmata),radiating,linear,and circumferential grabenfissure systems,and coronae.Its most prominent features
Pits are circular to elliptical,steep-sided,flat-bottomed depressions interpreted to form from collapse into a cavity.They occur on Earth,Venus and Mars and range in diameter from;00 m to several kilometres(e.g.
It is possible, the question on the existence of extraterrestrial life will be answered not as a result of its search for in other worlds removed by distances of dozens of parsecs but on the surface of Venus, i.e., of...It is possible, the question on the existence of extraterrestrial life will be answered not as a result of its search for in other worlds removed by distances of dozens of parsecs but on the surface of Venus, i.e., of the nearest planet of the Solar system. The search for “habitable zones” in extrasolar planetary systems is based on the postulate on “normal” physical conditions, i.e., the pressure, temperature, and maybe atmospheric composition similar to those on Earth. But could not such an approach be a kind of “terrestrial chauvinism”? Considering the conditions on Venus as a possible analogue of physical conditions on low-orbiting exoplanets of the “super-Earths” type, a new analysis of Venusian surface panoramas’ details has been made. These images were produced by the VENERA landers in 1975 and 1982. A few relatively large objects were found with size ranging from a decimeter to half meter and with unusual morphology. The objects were observed in some images, but were absent in the other or altered their shape. The article presents the obtained results and analyzes the evidence of reality of these objects.展开更多
文摘On March 1 and 5, 1982, experiments in television photography instrumented by the landers VENERA-13 and 14 returned panoramas of the Venus surface at the landing site. Over the past 31 years, no similar missions have been sent to Venus. In connection with the renewed interest in what was occurring during the experiment and to the discovery of manifestations of possible life revealed on some of the pictures, the panoramas were re-examined.?Analysis of treated once again VENERA-14 panoramic images revealed a?“snake”?object about 40 cm in size possessing apparent terramorphic features. The snake’s body stands out with its honeycomb, spotty surface against the stone plates close by. The “snake”?can be included into the list of the most significant findings of the hypothetical Venusian fauna. Apart from that, of interest is a?“dove”?object, although details of its structure cannot be discerned. The snake’s body show slow movements, which is another evidence of the Venusian fauna’s very slow style of activity, which appears to be associated with its energy constraints, and that is more likely, with the properties of its internal medium. The terramorphic features of the fauna, if they are confirmed, may point out outstandingly important and yet undiscovered general laws of the animated nature.
基金supported by Advanced Technique Research of Valvular Heart Disease Treatment Project(2015C03028)
文摘BACKGROUND: No retrievable and repositionable second generation transcatheter aortic valve is available in China. Here, we report the first-in-man implantation of the retrievable and repositionable VenusA-Plus valve. METHODS: A 76-year-old patient with symptomatic severe aortic stenosis and high surgical risk(STS 13.8%) was recommended for transcatheter aortic valve replacement(TAVR) by heart valve team. Type 0 bicuspid aortic valve with asymmetric calcification was identified by dual source computed tomography, and the unfavorable anatomies increased the possibility of malposition and paravalvular leakage during TAVR. Therefore, we used the retrievable and repositionable Venus APlus valve for the patient.RESULTS: Transfemoral TAVR was performed under local anesthesia with sedation, and a 26-mm VenusA-Plus valve was successfully implanted. No transvalvular pressure gradient and trace paravalvular leakage were found. CONCLUSION: The successful first-in-man implantation indicates the retrievable and repositionable Venus A-Plus valve is feasible in complicated TAVR cases such as bicuspid aortic valve.
基金supported by NSFC grants 41904156, 41974205, 41774171, 41574173, 41774167 and 41804157the Science and Technology Development Fund of Macao SAR (008/2016/A1 and 039/2013/A2)+3 种基金the China Postdoctoral Science Foundation (2019M651271)the financial support of the Shenzhen Science and Technology Research Program (JCYJ20170811154933612 and JCYJ20180306171918617)the 111 Project (B18017)supported by CAS Center for Excellence in Comparative Planetology
文摘With Venus Express magnetic field measurements at 32 Hz from 2006 to 2012, we investigate statistically the magnetic fluctuations in the near-Venusian space. The global spatial distribution of their spectral scaling features is presented in MHD and kinetic regimes. It can be observed that turbulence is a common phenomenon in the solar wind in both regimes. The solar wind MHD turbulence is modified at the Venusian bow shock;MHD turbulence is absent in the Venusian magnetosheath but present at the magnetosheath boundary layer. Pre-existing kinetic turbulence from the far upstream solar wind is modified in the near solar wind region, while kinetic turbulence can be extensively observed throughout the Venusian magnetosheath and in some regions of the induced magnetosphere. Our results reveal that, in the near-Venusian space, energy cascade can be developed at the boundary between magnetosheath and wake, and the turbulence-related dissipation of magnetic energy occurs extensively in the magnetosheath and the induced magnetosphere.
文摘Venusian coronae are large(60-2600 km diameter)tectono-magmatic features characterized by quasi-circular graben-fissure systems and topographic features such as a central dome,central depression,circular rim or circular
基金I want to express my gratitude to the auction houses,libraries,museums,photographic collections(Wikipedia,Wiki Commons Images),and private collections here cited for their assistance in granting me permission to photograph or reproduce the images in this essay.
文摘The Pre-Raphaelite painter Edward Burne-Jones(1833-1898)conceived the subject of The Mirror of Venus between 1865 and 1867.He painted two versions:a small version in gouache and oil and a larger version in oil on canvas.In composing this subject Burne-Jones was inspired by the poetic and chromatic description of a lyrical stanza on“The Hill of Venus”in the long epic poem Earthly Paradise,written by his close friend and collaborator William Morris.1 This study comprises three parts:Burne-Jones’s history of the paintings,his iconographical sources,and an iconological interpretation of The Mirror of Venus.
基金supported by the National Natural Science Foundation of China (41525016, 41525015, 41661164034, 41621063)the National Important Basic Research Project (2011CB811405)supported by the Thousand Young Talents Program of China
文摘The Venusian dayside ionosphere, similar to other planetary ionospheres, is produced primarily by ionization of its neutral upper atmosphere due to solar extreme ultraviolet (EUV) radiation. It has become clear that the expansion of the ionosphere may be strongly controlled by the EUV level, as exhibited in data collected by the Pioneer Venus Orbiter (PVO) during one solar cycle (1978 1992). However, the EUV-dependence of the Venusian dayside ionopause altitude, which defines the outer boundary of the ionosphere, remains obscure because the PVO crossed the dayside ionopause only during the solar maximum;its periapsis lifted too high during the solar minimum. Recently, during the period 2006 2014, which included the longest and quietest solar minimum of the past several decades, Venus Express (VEX) provided measurements of the photoelectron boundary (PEB) over the northern high-latitude region. Since the photoelectron boundary is closely related to the ionopause, we have an opportunity to analyze the EUV effect on the dayside ionopause by combining PVO and VEX observations. We have evaluated and then reduced the orbit bias effect in data from both PVO and VEX, and then used the results to derive a relationship between solar EUV level and the dayside ionopause altitude. We find that the dayside ionopause altitude increases as the solar EUV level increases, which is consistent with theoretical expectations.
基金This paper was supported by European Space Agency(ESA)contract 4000121195-Ministry of Science and Technology(MOST),Dragon 4 cooperation(ID:32275).Specifically,Subproject1-Topic1“Algorithm Development Exploiting Multitemporal and Multi Sensor Satellite Data for Improving Crop Classification,Biophysical and Agronomic Variables Retrieval and Yield Prediction”and by the Italian Space Agency(ASI)project PRISCAV(PRISMA Calibration/Validation).
文摘This paper is devoted to the development and testing of the optimal procedures for retrieving biophysical crop variables by exploiting the spectral information of current multispectral optical satellite Sentinel-2 and Venus and in view of the advent of the new Sino-EU hyperspectral satellite(e.g.,PRISMA,EnMAP,and GF-5).Two different methodologies devoted to the estimation of biophysical crop variables Leaf area index(LAI)and Leaf chlorophyll content(Cab)were evaluated:non-kernel-based and kernel-based Machine Learning Regression Algorithms(MLRA);Sentinel-2 and Venus data comparison for the analysis of the durum wheat-growing season.Results show that for Sentinel-2 data,Gaussian Process Regression(GPR)was the best performing algorithm for both LAI(R 2=0.89 and RMSE=0.59)and Cab(R 2=0.70 and RMSE=8.31).Whereas,for PRISMA simulated data the Kernel Ridge Regression(KRR)was the best performing algorithm among all the other MLRA(R 2=0.91 and RMSE=0.51)for LAI and(R 2=0.83 and RMSE=6.09)for Cab,respectively.Results of Sentinel-2 and Venus data for durum wheat-growing season were consistent with ground truth data and confirm also that SWIR bands,which are used as tie-points in the PROSAIL inversion,are extremely useful for an accurate retrieving of crop biophysical parameters.
文摘The Beta-Atla-Themis(BAT)region on Venus is characterized by large volcanic rises,major rift zones(chasmata),radiating,linear,and circumferential grabenfissure systems,and coronae.Its most prominent features
文摘Pits are circular to elliptical,steep-sided,flat-bottomed depressions interpreted to form from collapse into a cavity.They occur on Earth,Venus and Mars and range in diameter from;00 m to several kilometres(e.g.
文摘It is possible, the question on the existence of extraterrestrial life will be answered not as a result of its search for in other worlds removed by distances of dozens of parsecs but on the surface of Venus, i.e., of the nearest planet of the Solar system. The search for “habitable zones” in extrasolar planetary systems is based on the postulate on “normal” physical conditions, i.e., the pressure, temperature, and maybe atmospheric composition similar to those on Earth. But could not such an approach be a kind of “terrestrial chauvinism”? Considering the conditions on Venus as a possible analogue of physical conditions on low-orbiting exoplanets of the “super-Earths” type, a new analysis of Venusian surface panoramas’ details has been made. These images were produced by the VENERA landers in 1975 and 1982. A few relatively large objects were found with size ranging from a decimeter to half meter and with unusual morphology. The objects were observed in some images, but were absent in the other or altered their shape. The article presents the obtained results and analyzes the evidence of reality of these objects.
