To explore the response law of non-lethal large-size kinetic energy projectiles to blunt attack on skin tissue,and to evaluate the skin injury characteristics of the attacked personnel and the use safety of kinetic en...To explore the response law of non-lethal large-size kinetic energy projectiles to blunt attack on skin tissue,and to evaluate the skin injury characteristics of the attacked personnel and the use safety of kinetic energy projectiles.Based on the LS-DYNA simulation software,a three-layer skin simulation model and a Flash-Ball rubber bullet model are established,and the force-time and deformation-time biomechanical corridors of the Flash-Ball rubber bullet impacting human skin tissue are obtained.The corridor curve and the energy transfer and diffusion are analyzed and compared.The safety evaluation of the damage caused by the rubber bullet shooting a human body at different distances is carried out using the empirical formula of the penetration limit.Finally,the safe shooting distance is obtained.The results show that the model used in the simulation has a good correlation with the experimental data,its biomechanical corridor characteristics are different from those of conventional vehicle impact and smallsize projectile response characteristics.The energy transfer and action time of medium and low-speed impact may cause greater damage.The fat layer is the largest energy absorption unit.The minimum safe shooting distance to ensure skin tissue from penetrating damage is 15.8 m,and the limit specific kinetic energy of skin damage is 7.88 J/cm^(2).This study can be extended to the study of biomechanical response law and safety evaluation under the impact of the same type of large kinetic energy projectile,which provides an important theoretical reference for the police to use large kinetic energy projectiles to conduct safe shooting in peacekeeping operations.展开更多
Elevated serum cholesterol metabolism is associated with a reduced risk of lung cancer.Disrupted cholesterol metabolism is evident in both lung cancer patients and tumor cells.Inhibiting tumor cell cholesterol uptake ...Elevated serum cholesterol metabolism is associated with a reduced risk of lung cancer.Disrupted cholesterol metabolism is evident in both lung cancer patients and tumor cells.Inhibiting tumor cell cholesterol uptake or biosynthesis pathways,through the modulation of receptors and enzymes such as liver X receptor and sterolregulatory element binding protein 2,effectively restrains lung tumor growth.Similarly,promoting cholesterol excretion yields comparable effects.Cholesterol metabolites,including oxysterols and isoprenoids,play a crucial role in regulating cholesterol metabolism within tumor cells,consequently impacting cancer progression.In lung cancer patients,both the cholesterol levels in the tumor microenvironment and within tumor cells significantly influence cell growth,proliferation,and metastasis.The effects of cholesterol metabolism are further mediated by the reprogramming of immune cells such as T cells,B cells,macrophages,myeloid-derived suppressor cells,among others.Ongoing research is investigating drugs targeting cholesterol metabolism for clinical treatments.Statins,targeting the cholesterol biosynthesis pathway,are widely employed in lung cancer treatment,either as standalone agents or in combination with other drugs.Additionally,drugs focusing on cholesterol transportation have shown promise as effective therapies for lung cancer.In this review,we summarized current research regarding the rule of cholesterol metabolism and therapeutic advances in lung cancer.展开更多
Lead-zinc sulphide ore contains lead sulphide (galena), and zinc sulphide (sphalerite). In the first flotation stage, galena is rendered hydrophobic with an organic collector such as xanthate, while sphalerite is kept...Lead-zinc sulphide ore contains lead sulphide (galena), and zinc sulphide (sphalerite). In the first flotation stage, galena is rendered hydrophobic with an organic collector such as xanthate, while sphalerite is kept from floating by depressants, and in the second flotation stage, activator was used to activated zinc flotation. Since the organic regent used are different in the two flotation stage, wastewater from the second zinc flotation stage can’t be directly recycled to the first lead flotation stage. Wastewater from flotation process for concentrating lead-zinc sulphide ore often containing organic compounds such as diethyldithiocarbamate(DDTC), xanthate, terpenic oil(2# oil) and thionocarbamate esters (Z-200), are environmentally hazardous. Their removal from contaminated water and the reuse of the water is one of the main challenges facing lead-zinc sulphide ore processing plants. In this study, synthetic wastewater containing DDTC, xanthate, 2# oil and Z-200 at concentrations ranging from 21 to 42 mg/L was fed into an Ozone/Biological activated carbon (BAC) reactor. Analyses of the effluent indicated a chemical oxygen demand (COD) removal over 86.21% and Total organic carbon (TOC) removal over 90.00% were achieved under Hydraulic retention time (HRT) of 4h and O3 feeding concentration of 33.3mg/L. The effluent was further recycled to the lab scale lead concentrating process and no significant difference was found in compare with fresh water. Furthermore, lead-zinc sulphide mineral concentrating process was carried out at lab scale. The produced wastewater was treated by Ozone/BAC reactor at O3 feeding concentration of 16.7mg/L and HRT of 4h. The effluent analysis showed that TOC removal was 74.58%. This effluent was recycled to the lab scale lead-zinc sulphide mineral concentrating process and the recovery of lead was not affected. The results showed that by using Ozone/BAC technology, the lead-zinc sulphide mineral processing wastewater could be recycled.展开更多
Propellant gas flow has an important impact on the ionization and acceleration process of Hall effect thrusters (HETs). In this paper, a particle-in-cell numerical method is used to study the effect of the anode tem...Propellant gas flow has an important impact on the ionization and acceleration process of Hall effect thrusters (HETs). In this paper, a particle-in-cell numerical method is used to study the effect of the anode temperature, i.e., the flow speed of the propellant gas, on the discharge characteristics of a HET. The simulation results show that, no matter the magnitude of the discharge voltage, the calculated variation trends of performance parameters with the anode temperature are in good agreement with the experimental ones presented in the literature. Further mechanism analysis indicates that the magnitude of the electron temperature is responsible for the two opposing variation laws found under different discharge voltages. When the discharge voltage is low, the electron temperature is low, and so is the intensity of the propellant ionization; the variation of the thruster performance with the anode temperature is thereby determined by the variation of the neutral density that affects the propellant utilization efficiency. When the discharge voltage is high, the electron temperature is large enough to guarantee a high degree of the propellant utilization no matter the magnitude of the anode temperature. The change of the thruster performance with the anode temperature is thus dominated by the change of the electron temperature and consequently the electron-neutral collisions as well as the electron cross-field mobility that affect the current utilization efficiency.展开更多
Over the last decades,the species distribution model(SDM)has become an essential tool for studying the potential eff ects of climate change on species distribution.In this study,an ensemble SDM was developed to predic...Over the last decades,the species distribution model(SDM)has become an essential tool for studying the potential eff ects of climate change on species distribution.In this study,an ensemble SDM was developed to predict the changes in species distribution of swimming crab Portunus trituberculatus across diff erent seasons in the future(2050s and 2100s)under the climate scenarios of Representative Concentration Pathway(RCP)4.5 and RCP8.5.Results of the ensemble SDM indicate that the distribution of this species will move northward and exhibit evident seasonal variations.Among the four seasons,the suitable habitat for this species will be signifi cantly reduced in summer,with loss rates ranging from 45.23%(RCP4.5)to 88.26%(RCP.8.5)by the 2100s.The loss of habitat will mostly occur in the East China Sea and the southern part of the Yellow Sea,while a slight increase in habitat will occur in the northern part of the Bohai Sea.These fi ndings provide an information forecast for this species in the future.Such forecast will be helpful in improving fi shery management under climate change.展开更多
Comprehensive Summary Pd-mediated bioorthogonal cleavage reactions have been extensively utilized in the activation of prodrug molecules,precise regulation of protein function,and cellular engineering.However,the avai...Comprehensive Summary Pd-mediated bioorthogonal cleavage reactions have been extensively utilized in the activation of prodrug molecules,precise regulation of protein function,and cellular engineering.However,the availability of cleavable"caging"groups is quite limited,and their application in nucleic acid modification has seldom been reported.Herein,we introduce a method based on Pd-catalyzed reduction amination of azides as a decaging strategy to activate the activity of biomolecules.We designed modifications on the bioactive sites with azides or their derivatives to mask the related biological function,followed by the release of biological activity through Pd-catalyzed NaBH4 reduction amination reaction.This study has demonstrated that the strategy can effectively be used to activate bioactive molecules such as fluorescent probes,prodrugs,and to regulate the biological function of RNA,including reverse transcription extension,binding to ligands,and cleavage activity of the CRISPR-Cas system.All results confirm that this strategy provides an efficient and controllable"OFF to ON"biological switch,capable of achieving significant regulatory effects substoichiometrically,and is expected to be extended to other biological applications.展开更多
Comprehensive Summary Currently,CRISPR/Cas9 technology has found widespread applications across various domains.However,the utility of CRISPR/Cas9 is encumbered by issues pertaining to its reliability and safety,prima...Comprehensive Summary Currently,CRISPR/Cas9 technology has found widespread applications across various domains.However,the utility of CRISPR/Cas9 is encumbered by issues pertaining to its reliability and safety,primarily stemming from the uncontrolled activity of the system.Therefore,the design and development of CRISPR/Cas9 systems with controllable activity is of paramount importance.Biotin,characterized by its small molecular weight,and streptavidin,distinguished by its substantial spatial steric hindrance,can be harnessed as an ideal OFF switch(termed a"bioactivity brake")due to their interaction characteristics.In this work,we present a strategy that employs the streptavidin-biotin interaction as a"brake system"for CRISPR/Cas9,effectively allowing for the shutdown of the enzymatic activity of CRISPR/Cas9.展开更多
In order to analyze the influence of the addition of yttrium and manganese on the soot combustion performance and high temperature stability of CeO_(2) catalyst,a series of Y/Mn-modified CeO_(2) catalysts were prepare...In order to analyze the influence of the addition of yttrium and manganese on the soot combustion performance and high temperature stability of CeO_(2) catalyst,a series of Y/Mn-modified CeO_(2) catalysts were prepared.The effects of structural properties,textural properties,oxygen vacancies,Ce^(3+),surface adsorbed oxygen species,reduction properties and desorption properties of oxygen species on the activity were analyzed by various characterization methods.The results of the activity test show that the addition of manganese is beneficial to enhancement of the activity,while the addition of yttrium increases the amount of reactive oxygen species,but decreases the activity.After aging at 700℃,the activity of the CeMn catalyst decreases most sharply,while the catalytic activity of the CeY catalyst can be maintained to a certain extent.Interestingly,the addition of yttrium and manganese at the same time can stabilize the activity.The fundamental reason is that yttrium and manganese move to the surface of the solid solution after aging,which increases the reduction performance of the catalyst,thus contributing to the increase of activity.Although the activity of CeYMn catalyst decreases after aging at 800℃,it is still higher than that of other catalysts aged at 700℃.展开更多
Zeolites are a promising support for Pd catalysts in leanmethane(CH_(4))combustion.Herein,three types of zeolites(H-MOR,H-ZSM-5 and H-Y)were selected to estimate their structural effects and deactivation mechanisms in...Zeolites are a promising support for Pd catalysts in leanmethane(CH_(4))combustion.Herein,three types of zeolites(H-MOR,H-ZSM-5 and H-Y)were selected to estimate their structural effects and deactivation mechanisms in CH_(4)combustion.We show that variations in zeolite structure and surface acidity led to distinct changes in Pd states.Pd/H-MOR with external high-dispersing Pd nanoparticles exhibited the best apparent activity,with activation energy(Ea)at 73 kJ/mol,while Pd/H-ZSM-5 displayed the highest turnover frequency(TOF)at 19.6×10^(−3)sec^(−1),presumably owing to its large particles with more step sites providing active sites in one particle for CH_(4)activation.Pd/H-Y with dispersed PdO within pore channels and/or Pd2+ions on ion-exchange sites yielded the lowest apparent activity and TOF.Furthermore,Pd/H-MOR and Pd/H-ZSM-5 were both stable under a dry condition,but introducing 3 vol.%H_(2)O caused the CH_(4)conversion rate on Pd/H-MOR drop from 100%to 63%and that on Pd/H-ZSM-5 decreased remarkably from 82%to 36%.The former was shown to originate fromzeolite structural dealumination,and the latter principally owed to Pd aggregation and the loss of active PdO.展开更多
Phytoplankton play an irreplaceable role as producers in maintaining lake ecosystems.Nevertheless,scant attention has been given to investigating the dispersion of phytoplankton communities and the factors influencing...Phytoplankton play an irreplaceable role as producers in maintaining lake ecosystems.Nevertheless,scant attention has been given to investigating the dispersion of phytoplankton communities and the factors influencing them across expansive areas.In this study,we present the results of a survey on the distribution of phytoplankton community and the effects of different driving factors in 11 lakes along Inner Mongolia in July–August 2020.Non-metric multidimensional scaling analysis and variance decomposition(VPA)were used to elucidate the distribution of phytoplankton communities and the response of drivers.A total of 169 species of phytoplankton from 8 phyla were detected.Both the abundance and diversity of phytoplankton in the Inner Mongolia lakes showed a trend of high in the east and low in the west(with Daihai Lake as the boundary).The Margalef index of phytoplankton significantly negatively correlated with salinity(r=−0.707,P<0.05)and total dissolved solids(r=−0.720,P<0.05),and both density and biomass highly significantly positively correlated with the suspended solids,Chlorophyll a and trophic level index.The VPA explained 38.9%of the changes in the phytoplankton community with the highest rate of explanation of land use.Therefore,preventing anthropogenic impacts,as well as reducing nutrient loads,can effectively ensure the ecological diversity of lake phytoplankton in lake populations with large geographical spans and varying levels of nutrients.展开更多
The produced water from the oilfield was purified with filter material and then injected back into the ground.The serpentine filter material was easy to harden with the increase in filtration amount,which affected the...The produced water from the oilfield was purified with filter material and then injected back into the ground.The serpentine filter material was easy to harden with the increase in filtration amount,which affected the water quality.A superhydrophilic/underwater oleophobic serpentine filter material was successfully prepared by a simple method of coating modification,which exhibited long-lasting filtration of oily water,good filtration and anti-fouling properties,and resistance to harden.The film-forming material of the superhydrophilic/underwater oleophobic coating was composed of SiO_(2) particles with small size,which could completely and evenly cover the filter particle.The weight loss was only 7.6%after mechanical stirring for 90 min.Compared with the original filter material,the superhydrophilic/underwater oleophobic serpentine filter material showed a better anti-fouling ability and resistance to harden.The filtration of crude oil emulsion and oil slick sewage showed a better backwashing performance.After 35 cycles of continuous filtration of suspended solids in wastewater,the backwashing rate reached 78.4%.The results provided an effective method for the filtration of oily wastewater in the oilfield.展开更多
Ammonia has garnered recognition as a zero-carbon fuel due to its high-density hydrogen storage capacity and its convenience for storage and transportation.To address the challenges associated with the direct usage of...Ammonia has garnered recognition as a zero-carbon fuel due to its high-density hydrogen storage capacity and its convenience for storage and transportation.To address the challenges associated with the direct usage of ammonia,the development of NH_(3)-to-H_(2)conversion technologies has emerged as a promising and effective approach.Herein,we present for the first time that crystallized Sm_(2)O_(3−x)electrodes demonstrate high and stable electrocatalytic activities,including N_(2)evolution rate and Faradaic efficiency,for ammonia electrolysis in a non-aqueous electrolyte.It was observed that Sm^(2+)ions in samarium oxide play an indispensable role in the ammonia electrooxidation reaction on the anodes.Furthermore,the mechanism of ammonia electrooxidation has also been elucidated,laying the foundation for a better understanding of the relationship between local structure and electrochemical properties in order to facilitate research on Pt-free electrocatalysts for the electrolysis of ammonia into H_(2).展开更多
DNA 5-formylcytosine(5fC)is a prominent epigenetic modification within biological systems.Recent investigations have shed light on its pivotal role in governing cell fate,gene expression,and disease pathways.However,o...DNA 5-formylcytosine(5fC)is a prominent epigenetic modification within biological systems.Recent investigations have shed light on its pivotal role in governing cell fate,gene expression,and disease pathways.However,our comprehension of the precise control of the 5f site structure to influence its functionality remains limited.In this study,we have successfully achieved precise control over 5fc activity by harnessing the interaction between streptavidin and biotin.This research underscores the potential application of interactions between biomacromolecules and small molecules in advancing the field of DNA epigenetic functional regulation.展开更多
With the incredible growth of the scale and complexity of datasets,creating proper visualizations for users becomes more and more challenging in large datasets.Though several visualization recommendation systems have ...With the incredible growth of the scale and complexity of datasets,creating proper visualizations for users becomes more and more challenging in large datasets.Though several visualization recommendation systems have been proposed,so far,the lack of practical engineering inputs is still a major concern regarding the usage of visualization recommendations in the industry.In this paper,we proposed AVA,an open-sourced web-based framework for Automated Visual Analytics.AVA contains both empiric-driven and insight-driven visualization recommendation methods to meet the demands of creating aesthetic visualizations and understanding expressible insights respectively.The code is available at https://github.com/antvis/AVA.展开更多
Previous works employ the Large Language Model(LLM)like GPT-3 for knowledge-based Visual Question Answering(VQA).We argue that the inferential capacity of LLM can be enhanced through knowledge injection.Although metho...Previous works employ the Large Language Model(LLM)like GPT-3 for knowledge-based Visual Question Answering(VQA).We argue that the inferential capacity of LLM can be enhanced through knowledge injection.Although methods that utilize knowledge graphs to enhance LLM have been explored in various tasks,they may have some limitations,such as the possibility of not being able to retrieve the required knowledge.In this paper,we introduce a novel framework for knowledge-based VQA titled“Prompting Large Language Models with Knowledge-Injection”(PLLMKI).We use vanilla VQA model to inspire the LLM and further enhance the LLM with knowledge injection.Unlike earlier approaches,we adopt the LLM for knowledge enhancement instead of relying on knowledge graphs.Furthermore,we leverage open LLMs,incurring no additional costs.In comparison to existing baselines,our approach exhibits the accuracy improvement of over 1.3 and 1.7 on two knowledge-based VQA datasets,namely OK-VQA and A-OKVQA,respectively.展开更多
China has experienced rapid urbanization in recent decades along with dramatic economic growth. Previous studies have shown that urbanization has both positive and negative effects on health. However, there is a lack ...China has experienced rapid urbanization in recent decades along with dramatic economic growth. Previous studies have shown that urbanization has both positive and negative effects on health. However, there is a lack of research on the overall effects of urbanization on the epidemic transition of environmental health risks considering various pathways in China. In the present study, we studied the contributions of different aspects of urbanization in China to epidemic transitions using provincial and multi-year (1995, 2000, 2005, and 2010) panel data. Statistical models with fixed and random effects were developed to explore the impacts of different urbanization indicators on the overall epidemic tran- sition of environmental health (general model) and the changes in cause-specific mortality rates of typ- ical diseases (cause-specific models). The results show that the impacts of non-communicable diseases continue to grow during the urbanization process in China. The ratio of communicable disease-related mortality to non-communicable disease-related mortality continues to decrease over time. The general model shows that the improved medical conditions (coefficient =-0.0011, P= 0.037), the improved urban infrastructure (e.g., tap water supply) (coefficient = -0.00065, P 〈 0,001), and the rise in income (coefficient = -0.00027, P = 0.047) during the urbanization process are important factors that promote this overall epidemic transition. The cause-specific models show that the mechanisms behind the general model are complicated. More attention should be paid to non-communicable diseases in urban health management. Specific health policies for different diseases should incorporate the considerations of dif- ferent impact pathwavs of urbanization,展开更多
文摘To explore the response law of non-lethal large-size kinetic energy projectiles to blunt attack on skin tissue,and to evaluate the skin injury characteristics of the attacked personnel and the use safety of kinetic energy projectiles.Based on the LS-DYNA simulation software,a three-layer skin simulation model and a Flash-Ball rubber bullet model are established,and the force-time and deformation-time biomechanical corridors of the Flash-Ball rubber bullet impacting human skin tissue are obtained.The corridor curve and the energy transfer and diffusion are analyzed and compared.The safety evaluation of the damage caused by the rubber bullet shooting a human body at different distances is carried out using the empirical formula of the penetration limit.Finally,the safe shooting distance is obtained.The results show that the model used in the simulation has a good correlation with the experimental data,its biomechanical corridor characteristics are different from those of conventional vehicle impact and smallsize projectile response characteristics.The energy transfer and action time of medium and low-speed impact may cause greater damage.The fat layer is the largest energy absorption unit.The minimum safe shooting distance to ensure skin tissue from penetrating damage is 15.8 m,and the limit specific kinetic energy of skin damage is 7.88 J/cm^(2).This study can be extended to the study of biomechanical response law and safety evaluation under the impact of the same type of large kinetic energy projectile,which provides an important theoretical reference for the police to use large kinetic energy projectiles to conduct safe shooting in peacekeeping operations.
文摘Elevated serum cholesterol metabolism is associated with a reduced risk of lung cancer.Disrupted cholesterol metabolism is evident in both lung cancer patients and tumor cells.Inhibiting tumor cell cholesterol uptake or biosynthesis pathways,through the modulation of receptors and enzymes such as liver X receptor and sterolregulatory element binding protein 2,effectively restrains lung tumor growth.Similarly,promoting cholesterol excretion yields comparable effects.Cholesterol metabolites,including oxysterols and isoprenoids,play a crucial role in regulating cholesterol metabolism within tumor cells,consequently impacting cancer progression.In lung cancer patients,both the cholesterol levels in the tumor microenvironment and within tumor cells significantly influence cell growth,proliferation,and metastasis.The effects of cholesterol metabolism are further mediated by the reprogramming of immune cells such as T cells,B cells,macrophages,myeloid-derived suppressor cells,among others.Ongoing research is investigating drugs targeting cholesterol metabolism for clinical treatments.Statins,targeting the cholesterol biosynthesis pathway,are widely employed in lung cancer treatment,either as standalone agents or in combination with other drugs.Additionally,drugs focusing on cholesterol transportation have shown promise as effective therapies for lung cancer.In this review,we summarized current research regarding the rule of cholesterol metabolism and therapeutic advances in lung cancer.
文摘Lead-zinc sulphide ore contains lead sulphide (galena), and zinc sulphide (sphalerite). In the first flotation stage, galena is rendered hydrophobic with an organic collector such as xanthate, while sphalerite is kept from floating by depressants, and in the second flotation stage, activator was used to activated zinc flotation. Since the organic regent used are different in the two flotation stage, wastewater from the second zinc flotation stage can’t be directly recycled to the first lead flotation stage. Wastewater from flotation process for concentrating lead-zinc sulphide ore often containing organic compounds such as diethyldithiocarbamate(DDTC), xanthate, terpenic oil(2# oil) and thionocarbamate esters (Z-200), are environmentally hazardous. Their removal from contaminated water and the reuse of the water is one of the main challenges facing lead-zinc sulphide ore processing plants. In this study, synthetic wastewater containing DDTC, xanthate, 2# oil and Z-200 at concentrations ranging from 21 to 42 mg/L was fed into an Ozone/Biological activated carbon (BAC) reactor. Analyses of the effluent indicated a chemical oxygen demand (COD) removal over 86.21% and Total organic carbon (TOC) removal over 90.00% were achieved under Hydraulic retention time (HRT) of 4h and O3 feeding concentration of 33.3mg/L. The effluent was further recycled to the lab scale lead concentrating process and no significant difference was found in compare with fresh water. Furthermore, lead-zinc sulphide mineral concentrating process was carried out at lab scale. The produced wastewater was treated by Ozone/BAC reactor at O3 feeding concentration of 16.7mg/L and HRT of 4h. The effluent analysis showed that TOC removal was 74.58%. This effluent was recycled to the lab scale lead-zinc sulphide mineral concentrating process and the recovery of lead was not affected. The results showed that by using Ozone/BAC technology, the lead-zinc sulphide mineral processing wastewater could be recycled.
基金funded by National Natural Science Foundation of China(Nos.51507040,51736003 and 51777045)the Research Program(No.JSZL2016203C006)the Fundamental Research Funds for the Central Universities(No.HIT.NSRIF.2015079)
文摘Propellant gas flow has an important impact on the ionization and acceleration process of Hall effect thrusters (HETs). In this paper, a particle-in-cell numerical method is used to study the effect of the anode temperature, i.e., the flow speed of the propellant gas, on the discharge characteristics of a HET. The simulation results show that, no matter the magnitude of the discharge voltage, the calculated variation trends of performance parameters with the anode temperature are in good agreement with the experimental ones presented in the literature. Further mechanism analysis indicates that the magnitude of the electron temperature is responsible for the two opposing variation laws found under different discharge voltages. When the discharge voltage is low, the electron temperature is low, and so is the intensity of the propellant ionization; the variation of the thruster performance with the anode temperature is thereby determined by the variation of the neutral density that affects the propellant utilization efficiency. When the discharge voltage is high, the electron temperature is large enough to guarantee a high degree of the propellant utilization no matter the magnitude of the anode temperature. The change of the thruster performance with the anode temperature is thus dominated by the change of the electron temperature and consequently the electron-neutral collisions as well as the electron cross-field mobility that affect the current utilization efficiency.
基金Supported by the National Key Research and Development Program of China(Nos.2017YFA0604902,2017YFA0604904)the Zhejiang Provincial Natural Science Foundation of China(No.LR21D060003)+1 种基金the New Talent Program for College Students in Zhejiang Province(No.2016R411011)the Innovation Training Program for University students of Zhejiang Ocean University(No.2020-03)。
文摘Over the last decades,the species distribution model(SDM)has become an essential tool for studying the potential eff ects of climate change on species distribution.In this study,an ensemble SDM was developed to predict the changes in species distribution of swimming crab Portunus trituberculatus across diff erent seasons in the future(2050s and 2100s)under the climate scenarios of Representative Concentration Pathway(RCP)4.5 and RCP8.5.Results of the ensemble SDM indicate that the distribution of this species will move northward and exhibit evident seasonal variations.Among the four seasons,the suitable habitat for this species will be signifi cantly reduced in summer,with loss rates ranging from 45.23%(RCP4.5)to 88.26%(RCP.8.5)by the 2100s.The loss of habitat will mostly occur in the East China Sea and the southern part of the Yellow Sea,while a slight increase in habitat will occur in the northern part of the Bohai Sea.These fi ndings provide an information forecast for this species in the future.Such forecast will be helpful in improving fi shery management under climate change.
基金the National Natural Science Foundation of China(Nos.22177089,21721005,92153303,22037004,22177088)the Fundamental Research Funds for the Central Universities(2042021kf0211)Translational Medicine and Interdisciplinary Research Joint Fund of Zhongnan Hospital of Wuhan University(Grant No.ZNJC202309).
文摘Comprehensive Summary Pd-mediated bioorthogonal cleavage reactions have been extensively utilized in the activation of prodrug molecules,precise regulation of protein function,and cellular engineering.However,the availability of cleavable"caging"groups is quite limited,and their application in nucleic acid modification has seldom been reported.Herein,we introduce a method based on Pd-catalyzed reduction amination of azides as a decaging strategy to activate the activity of biomolecules.We designed modifications on the bioactive sites with azides or their derivatives to mask the related biological function,followed by the release of biological activity through Pd-catalyzed NaBH4 reduction amination reaction.This study has demonstrated that the strategy can effectively be used to activate bioactive molecules such as fluorescent probes,prodrugs,and to regulate the biological function of RNA,including reverse transcription extension,binding to ligands,and cleavage activity of the CRISPR-Cas system.All results confirm that this strategy provides an efficient and controllable"OFF to ON"biological switch,capable of achieving significant regulatory effects substoichiometrically,and is expected to be extended to other biological applications.
基金the National Natural Science Foundation of China(Nos.22177089,21721005,92153303,22037004,22177088)the Fundamental Research Funds for the Central Universities(2042023kf0204)Translational Medicine and Interdisciplinary Research Joint Fund of Zhongnan Hospital of Wuhan University(Grant No.ZNJC202309).
文摘Comprehensive Summary Currently,CRISPR/Cas9 technology has found widespread applications across various domains.However,the utility of CRISPR/Cas9 is encumbered by issues pertaining to its reliability and safety,primarily stemming from the uncontrolled activity of the system.Therefore,the design and development of CRISPR/Cas9 systems with controllable activity is of paramount importance.Biotin,characterized by its small molecular weight,and streptavidin,distinguished by its substantial spatial steric hindrance,can be harnessed as an ideal OFF switch(termed a"bioactivity brake")due to their interaction characteristics.In this work,we present a strategy that employs the streptavidin-biotin interaction as a"brake system"for CRISPR/Cas9,effectively allowing for the shutdown of the enzymatic activity of CRISPR/Cas9.
基金Project supported by the National Natural Science Foundation of China(21962021)the Yunnan Fundamental Research Projects(202001AU070121)+1 种基金the National Natural Science Foundation of China(51908091)the Special Basic Cooperative Research Programs of Yunnan Provincial Undergraduate Universities'Association(202101BA070001-084)。
文摘In order to analyze the influence of the addition of yttrium and manganese on the soot combustion performance and high temperature stability of CeO_(2) catalyst,a series of Y/Mn-modified CeO_(2) catalysts were prepared.The effects of structural properties,textural properties,oxygen vacancies,Ce^(3+),surface adsorbed oxygen species,reduction properties and desorption properties of oxygen species on the activity were analyzed by various characterization methods.The results of the activity test show that the addition of manganese is beneficial to enhancement of the activity,while the addition of yttrium increases the amount of reactive oxygen species,but decreases the activity.After aging at 700℃,the activity of the CeMn catalyst decreases most sharply,while the catalytic activity of the CeY catalyst can be maintained to a certain extent.Interestingly,the addition of yttrium and manganese at the same time can stabilize the activity.The fundamental reason is that yttrium and manganese move to the surface of the solid solution after aging,which increases the reduction performance of the catalyst,thus contributing to the increase of activity.Although the activity of CeYMn catalyst decreases after aging at 800℃,it is still higher than that of other catalysts aged at 700℃.
基金supported by the National Key R&D Program of China(No.2022YFC3701603)the National Natural Science Foundation of China(Nos.22106133,52070168)+1 种基金the Key R&D Plan of Zhejiang Province(No.2023C03127)the Fundamental Research Funds for the Central Universities(No.226-2022-00150).
文摘Zeolites are a promising support for Pd catalysts in leanmethane(CH_(4))combustion.Herein,three types of zeolites(H-MOR,H-ZSM-5 and H-Y)were selected to estimate their structural effects and deactivation mechanisms in CH_(4)combustion.We show that variations in zeolite structure and surface acidity led to distinct changes in Pd states.Pd/H-MOR with external high-dispersing Pd nanoparticles exhibited the best apparent activity,with activation energy(Ea)at 73 kJ/mol,while Pd/H-ZSM-5 displayed the highest turnover frequency(TOF)at 19.6×10^(−3)sec^(−1),presumably owing to its large particles with more step sites providing active sites in one particle for CH_(4)activation.Pd/H-Y with dispersed PdO within pore channels and/or Pd2+ions on ion-exchange sites yielded the lowest apparent activity and TOF.Furthermore,Pd/H-MOR and Pd/H-ZSM-5 were both stable under a dry condition,but introducing 3 vol.%H_(2)O caused the CH_(4)conversion rate on Pd/H-MOR drop from 100%to 63%and that on Pd/H-ZSM-5 decreased remarkably from 82%to 36%.The former was shown to originate fromzeolite structural dealumination,and the latter principally owed to Pd aggregation and the loss of active PdO.
基金funded by the National Natural Science Foundation of China(52279067 and 51869014)National Key Research and Development Program of China(2021YFC3201203)Open Project Program of the Ministry of Education Key Laboratory of Ecology and Resources Use of the Mongolian Plateau(KF2020006).
文摘Phytoplankton play an irreplaceable role as producers in maintaining lake ecosystems.Nevertheless,scant attention has been given to investigating the dispersion of phytoplankton communities and the factors influencing them across expansive areas.In this study,we present the results of a survey on the distribution of phytoplankton community and the effects of different driving factors in 11 lakes along Inner Mongolia in July–August 2020.Non-metric multidimensional scaling analysis and variance decomposition(VPA)were used to elucidate the distribution of phytoplankton communities and the response of drivers.A total of 169 species of phytoplankton from 8 phyla were detected.Both the abundance and diversity of phytoplankton in the Inner Mongolia lakes showed a trend of high in the east and low in the west(with Daihai Lake as the boundary).The Margalef index of phytoplankton significantly negatively correlated with salinity(r=−0.707,P<0.05)and total dissolved solids(r=−0.720,P<0.05),and both density and biomass highly significantly positively correlated with the suspended solids,Chlorophyll a and trophic level index.The VPA explained 38.9%of the changes in the phytoplankton community with the highest rate of explanation of land use.Therefore,preventing anthropogenic impacts,as well as reducing nutrient loads,can effectively ensure the ecological diversity of lake phytoplankton in lake populations with large geographical spans and varying levels of nutrients.
基金The National Natural Science Foundation of China(No.52071076)Opening Project of State Key Laboratory of Advanced Technology for Float Glass(Grant 2022KF03)are gratefully acknowledged.
文摘The produced water from the oilfield was purified with filter material and then injected back into the ground.The serpentine filter material was easy to harden with the increase in filtration amount,which affected the water quality.A superhydrophilic/underwater oleophobic serpentine filter material was successfully prepared by a simple method of coating modification,which exhibited long-lasting filtration of oily water,good filtration and anti-fouling properties,and resistance to harden.The film-forming material of the superhydrophilic/underwater oleophobic coating was composed of SiO_(2) particles with small size,which could completely and evenly cover the filter particle.The weight loss was only 7.6%after mechanical stirring for 90 min.Compared with the original filter material,the superhydrophilic/underwater oleophobic serpentine filter material showed a better anti-fouling ability and resistance to harden.The filtration of crude oil emulsion and oil slick sewage showed a better backwashing performance.After 35 cycles of continuous filtration of suspended solids in wastewater,the backwashing rate reached 78.4%.The results provided an effective method for the filtration of oily wastewater in the oilfield.
基金supported by the National Natural Science Foundation of China(No.22076081)China Postdoctoral Science Foundation(No.2022M721704).
文摘Ammonia has garnered recognition as a zero-carbon fuel due to its high-density hydrogen storage capacity and its convenience for storage and transportation.To address the challenges associated with the direct usage of ammonia,the development of NH_(3)-to-H_(2)conversion technologies has emerged as a promising and effective approach.Herein,we present for the first time that crystallized Sm_(2)O_(3−x)electrodes demonstrate high and stable electrocatalytic activities,including N_(2)evolution rate and Faradaic efficiency,for ammonia electrolysis in a non-aqueous electrolyte.It was observed that Sm^(2+)ions in samarium oxide play an indispensable role in the ammonia electrooxidation reaction on the anodes.Furthermore,the mechanism of ammonia electrooxidation has also been elucidated,laying the foundation for a better understanding of the relationship between local structure and electrochemical properties in order to facilitate research on Pt-free electrocatalysts for the electrolysis of ammonia into H_(2).
基金the National Natural Science Foundation of China(Nos.22177089,21721005,92153303,22037004,22177088)the Fundamental Research Funds for the Central Universities(2042021kf0211)Translational Medicine and Interdisciplinary Research Joint Fund of Zhongnan Hospital of Wuhan University(Grant No.ZNJC202309).
文摘DNA 5-formylcytosine(5fC)is a prominent epigenetic modification within biological systems.Recent investigations have shed light on its pivotal role in governing cell fate,gene expression,and disease pathways.However,our comprehension of the precise control of the 5f site structure to influence its functionality remains limited.In this study,we have successfully achieved precise control over 5fc activity by harnessing the interaction between streptavidin and biotin.This research underscores the potential application of interactions between biomacromolecules and small molecules in advancing the field of DNA epigenetic functional regulation.
基金National Natural Science Foundation of China(62132017)Zhejiang Provincial Natural Science Foundation of China(LD24F020011).
文摘With the incredible growth of the scale and complexity of datasets,creating proper visualizations for users becomes more and more challenging in large datasets.Though several visualization recommendation systems have been proposed,so far,the lack of practical engineering inputs is still a major concern regarding the usage of visualization recommendations in the industry.In this paper,we proposed AVA,an open-sourced web-based framework for Automated Visual Analytics.AVA contains both empiric-driven and insight-driven visualization recommendation methods to meet the demands of creating aesthetic visualizations and understanding expressible insights respectively.The code is available at https://github.com/antvis/AVA.
基金supported by the National Natural Science Foundation of China(No.62272100)Consulting Project of Chinese Academy of Engineering(No.2023-XY-09)Fundamental Research Funds for the Central Universities.
文摘Previous works employ the Large Language Model(LLM)like GPT-3 for knowledge-based Visual Question Answering(VQA).We argue that the inferential capacity of LLM can be enhanced through knowledge injection.Although methods that utilize knowledge graphs to enhance LLM have been explored in various tasks,they may have some limitations,such as the possibility of not being able to retrieve the required knowledge.In this paper,we introduce a novel framework for knowledge-based VQA titled“Prompting Large Language Models with Knowledge-Injection”(PLLMKI).We use vanilla VQA model to inspire the LLM and further enhance the LLM with knowledge injection.Unlike earlier approaches,we adopt the LLM for knowledge enhancement instead of relying on knowledge graphs.Furthermore,we leverage open LLMs,incurring no additional costs.In comparison to existing baselines,our approach exhibits the accuracy improvement of over 1.3 and 1.7 on two knowledge-based VQA datasets,namely OK-VQA and A-OKVQA,respectively.
基金supported by the National Natural Science Foundation of China(71433007)the National Key Research and Development Program of China(2016YFC0207603)supported by China Scholarship Council(CSC)under the State Scholarship Fund
文摘China has experienced rapid urbanization in recent decades along with dramatic economic growth. Previous studies have shown that urbanization has both positive and negative effects on health. However, there is a lack of research on the overall effects of urbanization on the epidemic transition of environmental health risks considering various pathways in China. In the present study, we studied the contributions of different aspects of urbanization in China to epidemic transitions using provincial and multi-year (1995, 2000, 2005, and 2010) panel data. Statistical models with fixed and random effects were developed to explore the impacts of different urbanization indicators on the overall epidemic tran- sition of environmental health (general model) and the changes in cause-specific mortality rates of typ- ical diseases (cause-specific models). The results show that the impacts of non-communicable diseases continue to grow during the urbanization process in China. The ratio of communicable disease-related mortality to non-communicable disease-related mortality continues to decrease over time. The general model shows that the improved medical conditions (coefficient =-0.0011, P= 0.037), the improved urban infrastructure (e.g., tap water supply) (coefficient = -0.00065, P 〈 0,001), and the rise in income (coefficient = -0.00027, P = 0.047) during the urbanization process are important factors that promote this overall epidemic transition. The cause-specific models show that the mechanisms behind the general model are complicated. More attention should be paid to non-communicable diseases in urban health management. Specific health policies for different diseases should incorporate the considerations of dif- ferent impact pathwavs of urbanization,