Objective:To evaluate the basic appearance and variation of the venous sinuses and veins in healthy individuals.Methods:Prospectively-recruited healthy volunteers completed a questionnaire and underwent magnetic reson...Objective:To evaluate the basic appearance and variation of the venous sinuses and veins in healthy individuals.Methods:Prospectively-recruited healthy volunteers completed a questionnaire and underwent magnetic resonance imaging plus contrast-enhanced magnetic resonance venography(CE-MRV)to measure their sinus diameters.Anatomical variations of cerebral venous sinuses were evaluated.Results:Fifty-eight individuals were included.The mean diameter of the left transverse sinus(LTS)(5.37±1.35 mm)was significantly smaller than that of the right transverse sinus(RTS)(6.65±1.57 mm)(P<0.001),and the average discrepancy was 19.2%.RTS dominance was noted in 55.1%of cases.Four superior sagittal sinus(SSS)anatomical variations were found.Type A was the most common and was present in 43 participants(74.1%).The SSS preferentially drained into the RTS in 32 patients(55.2%),and arachnoid granulation was observed in the transverse sinus(TS)and SSS in patients.According to our reclassification combined with Osborn’s previous research,we found that the SSS commonly drained into the RTS and that the straight sinus(StS)branched into both TSs.Conclusions:A 19%difference between the LTS and RTS provides a threshold for TS lateral dominance instead of a TS abnormality.Clinicians and radiologists should not ignore the influence of acquired pathology when the SSS drains in a non-RTS-dominant manner.Anatomical variations of the torcular herophili are frequent;the most commonly observed was the StS branching into both TSs,with the SSS draining into the RTS.展开更多
The robotics industry has seen rapid development in recent years due to the Corona Virus Disease 2019.With the development of sensors and smart devices,factories and enterprises have accumulated a large amount of data...The robotics industry has seen rapid development in recent years due to the Corona Virus Disease 2019.With the development of sensors and smart devices,factories and enterprises have accumulated a large amount of data in their daily production,which creates extremely favorable conditions for robots to perform machine learning.However,in recent years,people’s awareness of data privacy has been increasing,leading to the inability to circulate data between different enterprises,resulting in the emergence of data silos.The emergence of federated learning provides a feasible solution to this problem,and the combination of federated learning and multi-robot systems can break down data silos and improve the overall performance of robots.However,as scholars have studied more deeply,they found that federated learning has very limited privacy protection.Therefore,how to protect data privacy from infringement remains an important issue.In this paper,we first give a brief introduction to the current development of multi-robot and federated learning;second,we review three aspects of privacy protection methods commonly used,privacy protection methods for multi-robot,and Other Problems Faced by Multi-robot Systems,focusing on method comparisons and challenges;and finally draw conclusions and predict possible future research directions.展开更多
A yearlong monitoring program in the backwater area of Xiaojiang River(XBA)was launched in order to investigate the eutrophication of backwater areas in tributaries of the Yangtze River in the Three Gorges Reservoir(T...A yearlong monitoring program in the backwater area of Xiaojiang River(XBA)was launched in order to investigate the eutrophication of backwater areas in tributaries of the Yangtze River in the Three Gorges Reservoir(TGR)in China,starting after the impoundment water level of the TGR reached 156 m.From March 2007 to March 2008,the average concentration of total nitrogen(TN)and total phosphorus(TP)were(1553484)μg·L^(–1)and(6231)μg·L^(–1),respectively.The mean value of chlorophyll was(9.070.91)μg·L^(–1).The trophic level of XBA was meso-eutrophic,while the general nutrient limitation was phosphorus.The results indicated that XBA has a strong ability to purify itself and has non-point source pollution from terrestrial runoff.The variation of TN/TP ratio was caused by a variation in TN rather than in TP when TN/TP<22.N-fixation from cyanobacteria occurred and became an important process in overcoming the nitrogen deficit under a low TN/TP ratio.When TN/TP≥22,the variation of TP affected the TN/TP ratio more significantly than TN.The increase of TP in XBA was caused mainly by particulate phosphorus,which could originate from a non-point source as adsorptive inorganic forms after heavy rainfall and surface runoff.An increase in the river’s flow could also contribute to an unstable environment for the growth of phytoplankton.展开更多
Three-dimensional fluorescence spectroscopy was used to investigate the fluorescent properties of soil dissolved organic matter(DOM)in the water-levelfluctuation zone(WLFZ)of Kai County,Three Gorges Reservoir(TGR).Mos...Three-dimensional fluorescence spectroscopy was used to investigate the fluorescent properties of soil dissolved organic matter(DOM)in the water-levelfluctuation zone(WLFZ)of Kai County,Three Gorges Reservoir(TGR).Most of the soil DOM analyzed in this study was found to contain four fluorescence peaks.Peaks A and C represent humic-like fluorescence,whereas peaks B and D represent tryptophan-like fluorescence.Peaks E and F,which represent tyrosine-like fluorescence,only appeared in certain soils.Soil humus was the main source of DOM in soil,and higher concentration of soil DOM was found in the exposed soil than submerged soil.Compared to the peaks A and B,the fluorescence intensities of peaks C and D were strongly influenced by the fluctuating water level.Analysis of fluorescence intensities of different peaks in soil DOM showed that WLFZ soil was not contaminated significantly.Soil DOM contained at least two types of humic-like fluorescence groups and two types of protein-like fluorescence groups.The proportion of the content of peak A in soil organic matter was quite stable.The soil DOM in exposed soil had relatively high humification and aromaticity,and periodic submerging and exposure of soil had an impact on the humification of soil DOM.展开更多
Excess nitrogenous compounds are detrimental to natural water systems and to human health. To completely realize autohy- drogenotrophic nitrogen removal, a novel 3-dimensional biofilm-electrode reactor was designed. T...Excess nitrogenous compounds are detrimental to natural water systems and to human health. To completely realize autohy- drogenotrophic nitrogen removal, a novel 3-dimensional biofilm-electrode reactor was designed. Titanium was electroplated with ruthenium and used as the anode. Activated carbon fiber felt was used as the cathode. The reactor was separated into two chambers by a permeable membrane. The cathode chamber was filled with granular graphite and glass beads. The cathode and cathode chamber were inhabited with domesticated biofilm. In the absence of organic substances, a nitrogen removal efficiency of up to 91% was achieved at DO levels of 3.42 ± 0.37 mg/L when the applied current density was only 0.02 mA/cm^2. The oxidation of ammonium in biofilmelectrode reactors was also investigated. It was found that ammonium could be oxidized not only on the anode but also on particle electrodes in the cathode chamber of the biofilm-electrode reactor. Oxidation rates of ammonium and nitrogen removal efficiency were found to be affected by the electric current loading on the biofilm-electrode reactor. The kinetic model of ammonium at different electric currents was analyzed by a first-order reaction kinetics equation. The regression analysis implied that when the current density was less than 0.02 mA/cm^2, ammonium removal was positively correlated to the current density. However, when the current density was more than 0.02 mA/cm^2, the electric current became a limiting factor for the oxidation rate of ammonium and nitrogen removal efficiency.展开更多
In this study,three sequential batch biofilm reactors(SBBRs)were operated for 155 days to evaluate the performance of completely autotrophic nitrogen removal over nitrite(CANON)process under different aeration modes a...In this study,three sequential batch biofilm reactors(SBBRs)were operated for 155 days to evaluate the performance of completely autotrophic nitrogen removal over nitrite(CANON)process under different aeration modes and dissolved oxygen(DO).Synthetic wastewater with 160-mg NH_(4)^(+)-N/L was fed into the reactors.In the continuously-aerated reactor,the efficiency of the ammonium nitrogen conversion and total nitrogen(TN)removal reached 80% and 70%,respectively,with DO between 0.8–1.0 mg/L.Whereas in the intermittently-aerated reactor,at the aeration/non-aeration ratio of 1.0,ammonium was always under the detection limit and 86% of TN was removed with DO between 2.0–2.5 mg/L during the aeration time.Results show that CANON could be achieved in both continuous and intermittent aeration pattern.However,to achieve the same nitrogen removal efficiency,the DO needed in the intermittently-aerated sequential batch biofilm reactor(SBBR)during the aeration period was higher than that in the continuously-aerated SBBR.In addition,the DO in the CANON system should be adjusted to the aeration mode,and low DO was not a prerequisite to CANON process.展开更多
The development of colorimetric analysis technologies for the commercial cellphone platform has attracted great attention in environmental monitoring due to the low cost,high versatility,easy miniaturization,and wides...The development of colorimetric analysis technologies for the commercial cellphone platform has attracted great attention in environmental monitoring due to the low cost,high versatility,easy miniaturization,and widespread ownership of cellphones.This work demonstrates a cellphone-based colorimetric multi-channel sensor for quantifying multiple environmental contaminants simultaneously with high sensitivity and stability.To improve the sensitivity of the sensor,a delicate optical path system was created by using a diffraction grating to split six white beams transmitting through the multiple colored samples,which allows the cellphone CMOS camera to capture the diffracted light for image analysis.The proposed sensor is a universal colorimetric detection platform for a variety of environmental contaminants with the colorimetry assay in the range of 400–700 nm.By introducing the diffraction grating for splitting light,the sensitivity was improved by over six folds compared with a system that directly photographed transmitted light.As a successful proof-of-concept,the sensor was used to detect turbidity,orthophosphate,ammonia nitrogen and three heavy metals simultaneously with high sensitivity(turbidity:detection limit of 1.3 NTU,linear range of 5–400 NTU;ammonia nitrogen:0.014 mg/L,0.05–5 mg/L;orthophosphate:0.028 mg/L,0.1–10 mg/L;Cr(VI):0.0069 mg/L,0.01–0.5 mg/L;Fe:0.025 mg/L,0.1–2 mg/L;Zn:0.032 mg/L,0.05–2 mg/L)and reliability(relative standard deviations of six parallel measurements of 0.37%–1.60%and recoveries of 95.5%–106.0%in surface water).The miniature sensor demonstrated in-field sensing ability in environmental monitoring,which can be extended to point-of-care diagnosis and food safety control.展开更多
While David Pankenier has since the early 1980s made outstanding contributionsto the scholarship of ancient Chinese cosmology, astrology, and their politico-cultural consequences with his many fruitful articles, this ...While David Pankenier has since the early 1980s made outstanding contributionsto the scholarship of ancient Chinese cosmology, astrology, and their politico-cultural consequences with his many fruitful articles, this is his first single-authored monograph incorporating major discoveries and insights accumulated over the decades. The book is groundbreaking, not only in the sense that the particular topic is examined with unprecedented intensity and profoundness, but also because it provides ＂an introduction to diverse aspects of an understudied field＂ （p. 5）, making the frameworks, terminologies and sources of early astral sciences in China more accessible.展开更多
基金supported by the National Natural Science Foundation of China(82027802)the Pharmaceutical Collaboration Project of the Beijing Science and Technology Commission(Z181100001918026)the Talents Gathering Project of Xuanwu Hospital,Capital Medical University.
文摘Objective:To evaluate the basic appearance and variation of the venous sinuses and veins in healthy individuals.Methods:Prospectively-recruited healthy volunteers completed a questionnaire and underwent magnetic resonance imaging plus contrast-enhanced magnetic resonance venography(CE-MRV)to measure their sinus diameters.Anatomical variations of cerebral venous sinuses were evaluated.Results:Fifty-eight individuals were included.The mean diameter of the left transverse sinus(LTS)(5.37±1.35 mm)was significantly smaller than that of the right transverse sinus(RTS)(6.65±1.57 mm)(P<0.001),and the average discrepancy was 19.2%.RTS dominance was noted in 55.1%of cases.Four superior sagittal sinus(SSS)anatomical variations were found.Type A was the most common and was present in 43 participants(74.1%).The SSS preferentially drained into the RTS in 32 patients(55.2%),and arachnoid granulation was observed in the transverse sinus(TS)and SSS in patients.According to our reclassification combined with Osborn’s previous research,we found that the SSS commonly drained into the RTS and that the straight sinus(StS)branched into both TSs.Conclusions:A 19%difference between the LTS and RTS provides a threshold for TS lateral dominance instead of a TS abnormality.Clinicians and radiologists should not ignore the influence of acquired pathology when the SSS drains in a non-RTS-dominant manner.Anatomical variations of the torcular herophili are frequent;the most commonly observed was the StS branching into both TSs,with the SSS draining into the RTS.
基金the National Natural Science Foundation of China(No.62063006)to the Natural Science Foundation of Guangxi Province(No.2023GXNSFAA026025)+2 种基金to the Innovation Fund of Chinese Universities Industry-University-Research(ID:2021RYC06005)to the Research Project for Young and Middle-Aged Teachers in Guangxi Universities(ID:2020KY15013)to the Special Research Project of Hechi University(ID:2021GCC028).
文摘The robotics industry has seen rapid development in recent years due to the Corona Virus Disease 2019.With the development of sensors and smart devices,factories and enterprises have accumulated a large amount of data in their daily production,which creates extremely favorable conditions for robots to perform machine learning.However,in recent years,people’s awareness of data privacy has been increasing,leading to the inability to circulate data between different enterprises,resulting in the emergence of data silos.The emergence of federated learning provides a feasible solution to this problem,and the combination of federated learning and multi-robot systems can break down data silos and improve the overall performance of robots.However,as scholars have studied more deeply,they found that federated learning has very limited privacy protection.Therefore,how to protect data privacy from infringement remains an important issue.In this paper,we first give a brief introduction to the current development of multi-robot and federated learning;second,we review three aspects of privacy protection methods commonly used,privacy protection methods for multi-robot,and Other Problems Faced by Multi-robot Systems,focusing on method comparisons and challenges;and finally draw conclusions and predict possible future research directions.
基金the Western China Action Program of China Academy of Science(No.KZCX2-XB2-07-02)the Grand S&T Project of Chongqing Municipality(No.CSTC2006BA7030).
文摘A yearlong monitoring program in the backwater area of Xiaojiang River(XBA)was launched in order to investigate the eutrophication of backwater areas in tributaries of the Yangtze River in the Three Gorges Reservoir(TGR)in China,starting after the impoundment water level of the TGR reached 156 m.From March 2007 to March 2008,the average concentration of total nitrogen(TN)and total phosphorus(TP)were(1553484)μg·L^(–1)and(6231)μg·L^(–1),respectively.The mean value of chlorophyll was(9.070.91)μg·L^(–1).The trophic level of XBA was meso-eutrophic,while the general nutrient limitation was phosphorus.The results indicated that XBA has a strong ability to purify itself and has non-point source pollution from terrestrial runoff.The variation of TN/TP ratio was caused by a variation in TN rather than in TP when TN/TP<22.N-fixation from cyanobacteria occurred and became an important process in overcoming the nitrogen deficit under a low TN/TP ratio.When TN/TP≥22,the variation of TP affected the TN/TP ratio more significantly than TN.The increase of TP in XBA was caused mainly by particulate phosphorus,which could originate from a non-point source as adsorptive inorganic forms after heavy rainfall and surface runoff.An increase in the river’s flow could also contribute to an unstable environment for the growth of phytoplankton.
基金This work was supported by the National Science and Technology Support Project(Grant No.2008BAD98B04)National Mega-projects of Science Research for Water Environment improvement(Grant Nos.2009ZX07104-002,and 2009ZX07104-003).
文摘Three-dimensional fluorescence spectroscopy was used to investigate the fluorescent properties of soil dissolved organic matter(DOM)in the water-levelfluctuation zone(WLFZ)of Kai County,Three Gorges Reservoir(TGR).Most of the soil DOM analyzed in this study was found to contain four fluorescence peaks.Peaks A and C represent humic-like fluorescence,whereas peaks B and D represent tryptophan-like fluorescence.Peaks E and F,which represent tyrosine-like fluorescence,only appeared in certain soils.Soil humus was the main source of DOM in soil,and higher concentration of soil DOM was found in the exposed soil than submerged soil.Compared to the peaks A and B,the fluorescence intensities of peaks C and D were strongly influenced by the fluctuating water level.Analysis of fluorescence intensities of different peaks in soil DOM showed that WLFZ soil was not contaminated significantly.Soil DOM contained at least two types of humic-like fluorescence groups and two types of protein-like fluorescence groups.The proportion of the content of peak A in soil organic matter was quite stable.The soil DOM in exposed soil had relatively high humification and aromaticity,and periodic submerging and exposure of soil had an impact on the humification of soil DOM.
基金supported by the Water Special Project(No.2009ZX07104 002)the Fundamental Research Funds for the Central Universities of China(No.CQDXWL2012-040)
文摘Excess nitrogenous compounds are detrimental to natural water systems and to human health. To completely realize autohy- drogenotrophic nitrogen removal, a novel 3-dimensional biofilm-electrode reactor was designed. Titanium was electroplated with ruthenium and used as the anode. Activated carbon fiber felt was used as the cathode. The reactor was separated into two chambers by a permeable membrane. The cathode chamber was filled with granular graphite and glass beads. The cathode and cathode chamber were inhabited with domesticated biofilm. In the absence of organic substances, a nitrogen removal efficiency of up to 91% was achieved at DO levels of 3.42 ± 0.37 mg/L when the applied current density was only 0.02 mA/cm^2. The oxidation of ammonium in biofilmelectrode reactors was also investigated. It was found that ammonium could be oxidized not only on the anode but also on particle electrodes in the cathode chamber of the biofilm-electrode reactor. Oxidation rates of ammonium and nitrogen removal efficiency were found to be affected by the electric current loading on the biofilm-electrode reactor. The kinetic model of ammonium at different electric currents was analyzed by a first-order reaction kinetics equation. The regression analysis implied that when the current density was less than 0.02 mA/cm^2, ammonium removal was positively correlated to the current density. However, when the current density was more than 0.02 mA/cm^2, the electric current became a limiting factor for the oxidation rate of ammonium and nitrogen removal efficiency.
基金This study was supported by the National Natural Science Foundation of China(Grant No.50608071)the Key Grant Project of Ministry of Education of China(Grant No.308020)+1 种基金Chongqing University Postgraduates’Science and Innovation Fund(No.200801A1A0180277)Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20050611010).
文摘In this study,three sequential batch biofilm reactors(SBBRs)were operated for 155 days to evaluate the performance of completely autotrophic nitrogen removal over nitrite(CANON)process under different aeration modes and dissolved oxygen(DO).Synthetic wastewater with 160-mg NH_(4)^(+)-N/L was fed into the reactors.In the continuously-aerated reactor,the efficiency of the ammonium nitrogen conversion and total nitrogen(TN)removal reached 80% and 70%,respectively,with DO between 0.8–1.0 mg/L.Whereas in the intermittently-aerated reactor,at the aeration/non-aeration ratio of 1.0,ammonium was always under the detection limit and 86% of TN was removed with DO between 2.0–2.5 mg/L during the aeration time.Results show that CANON could be achieved in both continuous and intermittent aeration pattern.However,to achieve the same nitrogen removal efficiency,the DO needed in the intermittently-aerated sequential batch biofilm reactor(SBBR)during the aeration period was higher than that in the continuously-aerated SBBR.In addition,the DO in the CANON system should be adjusted to the aeration mode,and low DO was not a prerequisite to CANON process.
基金supported by the National Key Research and Development Program of China(No.2019YFD1100501).
文摘The development of colorimetric analysis technologies for the commercial cellphone platform has attracted great attention in environmental monitoring due to the low cost,high versatility,easy miniaturization,and widespread ownership of cellphones.This work demonstrates a cellphone-based colorimetric multi-channel sensor for quantifying multiple environmental contaminants simultaneously with high sensitivity and stability.To improve the sensitivity of the sensor,a delicate optical path system was created by using a diffraction grating to split six white beams transmitting through the multiple colored samples,which allows the cellphone CMOS camera to capture the diffracted light for image analysis.The proposed sensor is a universal colorimetric detection platform for a variety of environmental contaminants with the colorimetry assay in the range of 400–700 nm.By introducing the diffraction grating for splitting light,the sensitivity was improved by over six folds compared with a system that directly photographed transmitted light.As a successful proof-of-concept,the sensor was used to detect turbidity,orthophosphate,ammonia nitrogen and three heavy metals simultaneously with high sensitivity(turbidity:detection limit of 1.3 NTU,linear range of 5–400 NTU;ammonia nitrogen:0.014 mg/L,0.05–5 mg/L;orthophosphate:0.028 mg/L,0.1–10 mg/L;Cr(VI):0.0069 mg/L,0.01–0.5 mg/L;Fe:0.025 mg/L,0.1–2 mg/L;Zn:0.032 mg/L,0.05–2 mg/L)and reliability(relative standard deviations of six parallel measurements of 0.37%–1.60%and recoveries of 95.5%–106.0%in surface water).The miniature sensor demonstrated in-field sensing ability in environmental monitoring,which can be extended to point-of-care diagnosis and food safety control.
文摘While David Pankenier has since the early 1980s made outstanding contributionsto the scholarship of ancient Chinese cosmology, astrology, and their politico-cultural consequences with his many fruitful articles, this is his first single-authored monograph incorporating major discoveries and insights accumulated over the decades. The book is groundbreaking, not only in the sense that the particular topic is examined with unprecedented intensity and profoundness, but also because it provides ＂an introduction to diverse aspects of an understudied field＂ （p. 5）, making the frameworks, terminologies and sources of early astral sciences in China more accessible.
