AIM: To evaluate the efficacy and safety of active removal of silicone oil with low and high viscosity through a 23-gauge transconjunctival cannula using an external vacuum pump.METHODS: This study was conducted as a ...AIM: To evaluate the efficacy and safety of active removal of silicone oil with low and high viscosity through a 23-gauge transconjunctival cannula using an external vacuum pump.METHODS: This study was conducted as a prospective, interventional case series. A total of 22 eyes of 21 patients [1000 centistokes(c St): 17 eyes, 5700 c St:5 eyes] were included in this study. All patients underwent active silicone oil removal via the entire lumen of a 23-gauge microcannula with suction pressure of a650-700 mm Hg vacuum using an external vacuum pump. A tubing adaptor from the Total Plus Pak誖(Alcon,Fort Worth, USA) was used to join the microcannula and silicone vacuum tube connected to an external vacuum pump. Main outcome measures were mean removal time,changes of intraocular pressure(IOP) and visual acuity,and intraoperative and postoperative complications.RESULTS: Mean removal time(min) was 1.49±0.43 for1000 c St and 7. 12 ± 1. 27 for 5700 c St. The IOP was18.57±7.48 mm Hg at baseline, 11.68 ±4.55 mm Hg at day1 postoperatively(P <0.001), and 15.95±4.92, 16.82±3.81,17.41 ±3.50, and 17.09 ±3.01 mm Hg after one week, one month, three months, and six months, respectively. All patients showed improved or stabilized visual acuity.There was no occurrence of intraoperative or postoperative complications during the follow up period.CONCLUSION: This technique for active removal of silicone oil through a 23-gauge cannula using an external vacuum pump is fast, effective, and safe as well as economical for silicone oil with both low and high viscosity in all eyes with pseudophakia, aphakia, or phakia.展开更多
Recent studies of the space debris environment in Low Earth Orbit(LEO)have shown that the critical density of space debris has been reached in certain regions.The Active Debris Removal(ADR)mission,to mitigate the spac...Recent studies of the space debris environment in Low Earth Orbit(LEO)have shown that the critical density of space debris has been reached in certain regions.The Active Debris Removal(ADR)mission,to mitigate the space debris density and stabilize the space debris environment,has been considered as a most effective method.In this paper,a novel two-level optimization strategy for multi-debris removal mission in LEO is proposed,which includes the low-level and high-level optimization process.To improve the overall performance of the multi-debris active removal mission and obtain multiple Pareto-optimal solutions,the ADR mission is seen as a Time-Dependant Traveling Salesman Problem(TDTSP)with two objective functions to minimize the total mission duration and the total propellant consumption.The problem includes the sequence optimization to determine the sequence of removal of space debris and the transferring optimization to define the orbital maneuvers.Two optimization models for the two-level optimization strategy are built in solving the multi-debris removal mission,and the optimal Pareto solution is successfully obtained by using the non-dominated sorting genetic algorithm II(NSGA-II).Two test cases are presented,which show that the low level optimization strategy can successfully obtain the optimal sequences and the initial solution of the ADR mission and the high level optimization strategy can efficiently and robustly find the feasible optimal solution for long duration perturbed rendezvous problem.展开更多
Denitrification is an important process of nitrogen removal in lake ecosystems.However,the importance of denitrification across the entire soil-depth gradients including subsurface layers remains poorly understood.Thi...Denitrification is an important process of nitrogen removal in lake ecosystems.However,the importance of denitrification across the entire soil-depth gradients including subsurface layers remains poorly understood.This study aims to determine the spatial pattern of soil denitrification enzyme activity(DEA) and its environmental determinants across the entire soil depth gradients in the raised fields in Baiyang Lake,North China.In two different zones of the raised fields(i.e.,water boundary vs.main body of the raised fields),the soil samples from 1.0 m to 1.1 m depth were collected,and the DEA and following environmental determinants were quantified:soil moisture,p H,total nitrogen(TN),ammonia nitrogen(NH4+-N),nitrate nitrogen(NO3–-N),total organic carbon(TOC),and rhizome biomass of Phragmites australis.The results showed that the soil DEA and environmental factors had a striking zonal distribution across the entire soil depth gradients.The soil DEA reached two peak values in the upper and middle soil layers,indicating that denitrification are important in both topsoil and subsurface of the raised fields.The correlation analysis showed that the DEA is negatively correlated with the soil depth(p < 0.05).However,this phenomenon did not occur in the distance to the water edge,except in the upper layers(from 0.2 m to 0.7 m) of the boundary zone of the raised fields.In the main body of the raised fields,the DEA level remained high;however,it showed no significant relationship with the distance to the water edge.The linear regression analysis showed significant positive correlation of the DEA with the soil TN,NO3–-N,NH4+-N,and TOC;whereas it showed negative correlation with soil p H.No significant correlations with soil moisture and temperature were observed.A positive correlation was also found between the DEA and rhizome biomass of P.australis.展开更多
In this study,hierarchical Ag/La2 O2 CO3 micro/nanostructures(MNSs)were synthesized by in situ loading Ag nanoparticles(NPs)on the surface of the La2 O2 CO3 MNSs.The prepared La2 O2 CO3 MNSs present flower-like shape ...In this study,hierarchical Ag/La2 O2 CO3 micro/nanostructures(MNSs)were synthesized by in situ loading Ag nanoparticles(NPs)on the surface of the La2 O2 CO3 MNSs.The prepared La2 O2 CO3 MNSs present flower-like shape and can be tuned by the molar ratio of La(NO3)3 and CO(NH2)2.In the molar ratio of 1:2 to 1:55,the La2 O2 CO3 MNSs mainly consist of polyhedral rods,irregular rods and irregular spindles and their size is about 10,8 and 7μm,respectively.After loading Ag NPs,the spindle-like Ag/La2 O2 CO3 MNSs were used for phosphate removal and antibacterial activity.At the initial phosphate concentration of20 mg/L,the removal rate is 59.6%.The Ag/La2 O2 CO3 MNSs have significant antibacterial activity and their MIC values for S.aureus and E.coli are 31.3 and 15.6μg/mL,respectively.The results indicate that Ag/La2 O2 CO3 MNSs may have good application prospects in open water to inhibit bacterial growth.展开更多
AIM:To report a simple approach to actively remove high viscosity silicone oil through a 23-gauge cannula via pars plana.METHODS:Forty-eight eyes of 48 patients underwent silicone oil(5700 centistokes) removal(SO...AIM:To report a simple approach to actively remove high viscosity silicone oil through a 23-gauge cannula via pars plana.METHODS:Forty-eight eyes of 48 patients underwent silicone oil(5700 centistokes) removal(SOR) were enrolled.A section of blood transfusion set was prepared to connect a standard 23-gauge cannula and vitrectomy machine.Silicone oil was removed with suction of500-mm Hg vacuum through the cannula.Main outcome measures were SOR duration,number of sutured sites,intraocular pressure(IOP),best-corrected visual acuity(BCVA),and complications.RESULTS:Silicone oil was successfully removed in all cases.The mean SOR time was 5.70±0.85 min.Nine eyes(18.75%) needed suture partial sclerotomies.No intraoperative complications were noted.Transient hypotony(≤8 mm Hg) was seen in 3 eyes(6.25%) on postoperative day 1,but all resolved within 1wk.Retinal reattachment was achieved in all cases and no other postoperative complications were noted during 3-month following-up.BCVA at the final visit improved or stabilized in all patients comparing to the preoperative level.CONCLUSION:Active removal of high viscosity silicone oil through a 23-gauge instrument cannula jointed with blood transfusion set is a practical and reliable technique when considering two sides of efficacy and safety.展开更多
Objective: To study the targeted point and mechanism of the function of the blood-activating and stasis-removing Chinese drugs, Paeoniae Radix 801(PR801) in its cardiovascular protective effects and its specific bind...Objective: To study the targeted point and mechanism of the function of the blood-activating and stasis-removing Chinese drugs, Paeoniae Radix 801(PR801) in its cardiovascular protective effects and its specific binding with endothelin 1(ET-1) as well as the dynamics of the two's interactive function by means of using affinity biosensors: IAsys Plus and quartz crystal microbalance (IAQCM). Methods: ET-1 was immobilized on the surfaces of IAQCM by using the new surface modification methods. The PR801 in the solution was detected by modified substrates and the specific binding between PR801 and ET-1 was studied. Results: The curves went up or down after adding PR801.There is specific binding between PR801 and ET-1. The bound mass were 0.458 ng/mm 2 and 133.54 ng/cm 2, respectively. There exists relatively good stability with these two methods. Conclusion: The affinity biosensors: IAQCM can be used to study the interaction mechanism between PR801 and ET-1, providing a new way to study the interaction mechanism of TCM. PR801 can bind ET-1 specifically in the experiments. Therefore, ET-1 is another target that PR801 can bind specifically besides thromboxane A 2.展开更多
The treatment of hy-pertensive cerebral hemorrhage(HCH)by activatingblood circulation to removestasis(ABCRS)is a newtherapeutic approach,which is initiated by clinical specialists of TCM andintegrative Chinese andwest...The treatment of hy-pertensive cerebral hemorrhage(HCH)by activatingblood circulation to removestasis(ABCRS)is a newtherapeutic approach,which is initiated by clinical specialists of TCM andintegrative Chinese andwestern medicine.Al-though it is not a flawless展开更多
Studies have shown that traditional Chinese medicines have clear curative effects in the treatment of vitiligo with few side effects.Through literature research and clinical observation,the study summarized the etiolo...Studies have shown that traditional Chinese medicines have clear curative effects in the treatment of vitiligo with few side effects.Through literature research and clinical observation,the study summarized the etiology and pathogenesis of vitiligo in traditional Chinese medicine as"deficiency,toxin,and stasis",formulated the method of invigorating qi,promoting blood circulation and detoxification,and prescribed Fuse Hexue Jiawei Decoction for the treatment of vitiligo.展开更多
Space debris is growing dramatically with the rapid pace of human exploration of space,which seriously threatens the safety of artificial spacecraft in orbit.Therefore,the active debris removal(ADR)is important.This r...Space debris is growing dramatically with the rapid pace of human exploration of space,which seriously threatens the safety of artificial spacecraft in orbit.Therefore,the active debris removal(ADR)is important.This review aims to review the ADR methods and to advance related research in the future.The current research and development status are clearly demonstrated by mapping knowledge domain and charts.In this paper,the latest research results are classified and summarized in detail from two aspects of space debris capture and removal.The scheme comparison and evaluation of all ADR methods are performed,and the applicable scopes of various methods are summarized.Each ADR method is scored using a cobweb evaluation model based on six indicators.Future development of ADR is discussed to promote further research interest.展开更多
OBJECTIVE: To evaluate the anti-platelet aggregation effects of extracts from 31 Traditional Chinese Medicines(TCM) with the property of activating blood and resolving stasis in terms of TCM theory.METHODS: The 31 TCM...OBJECTIVE: To evaluate the anti-platelet aggregation effects of extracts from 31 Traditional Chinese Medicines(TCM) with the property of activating blood and resolving stasis in terms of TCM theory.METHODS: The 31 TCMs extracts were prepared using water, 90% ethanol and ethyl acetate., and the effects on anti-platelet aggregation were tested on a platelet aggregation analyzer in vitro with adenosine 5'-diphosphate, bovine thrombin and arachi-donic acid(AA) as aggregation inducers, respectively. Aspirin was the positive control.RESULTS: Lots of the tested TCMs had inhibitory effects with concentration-dependent manner on platelet aggregations induced by various agonists.Especially, some of the TCMs such as Chuanxiong(Rhizoma Chuanxiong), Yanhusuo(Rhizoma Corydalis Yanhusuo) and Danshen(Radix Salviae Miltiorrhizae) showed good anti-platelet aggregation effect similar or higher than that in positive control group.CONCLUSION: The study provided scientific references that several TCMs such as Chuanxiong(Rhizoma Chuanxiong), Yanhusuo(Rhizoma Corydalis Yanhusuo) and Danshen(Radix Salviae Miltiorrhizae),possess the property of anti-platelet aggregation.展开更多
When adding sufficient chlorine to achieve breakpoint chlorination to source water containing high concentration of ammonia during drinking water treatment, high concentrations of disinfection by-products(DBPs) may ...When adding sufficient chlorine to achieve breakpoint chlorination to source water containing high concentration of ammonia during drinking water treatment, high concentrations of disinfection by-products(DBPs) may form. If N-nitrosamine precursors are present, highly toxic N-nitrosamines, primarily N-nitrosodimethylamine(NDMA), may also form. Removing their precursors before disinfection should be a more effective way to minimize these DBPs formation. In this study, zeolites and activated carbon were examined for ammonia and N-nitrosamine precursor removal when incorporated into drinking water treatment processes.The test results indicate that Mordenite zeolite can remove ammonia and five of seven N-nitrosamine precursors efficiently by single step adsorption test. The practical applicability was evaluated by simulation of typical drinking water treatment processes using six-gang stirring system. The Mordenite zeolite was applied at the steps of lime softening, alum coagulation, and alum coagulation with powdered activated carbon(PAC) sorption. While the lime softening process resulted in poor zeolite performance, alum coagulation did not impact ammonia and N-nitrosamine precursor removal. During alum coagulation, more than67% ammonia and 70%–100% N-nitrosamine precursors were removed by Mordenite zeolite(except 3-(dimethylaminomethyl)indole(DMAI) and 4-dimethylaminoantipyrine(DMAP)). PAC effectively removed DMAI and DMAP when added during alum coagulation. A combination of the zeolite and PAC selected efficiently removed ammonia and all tested seven N-nitrosamine precursors(dimethylamine(DMA), ethylmethylamine(EMA), diethylamine(DEA), dipropylamine(DPA), trimethylamine(TMA), DMAP, and DMAI) during the alum coagulation process.展开更多
In this paper,a new mission model,called a multi-debris active removal mission with partial debris capture strategy,is proposed.The model assumes that a platform only captures part of the scheduled debris at a time an...In this paper,a new mission model,called a multi-debris active removal mission with partial debris capture strategy,is proposed.The model assumes that a platform only captures part of the scheduled debris at a time and then releases these debris pieces to a disposal orbit.This process is then repeated until all of the scheduled debris is removed.A genetic algorithm with a multiparameter concatenated coding method is designed to optimize the plan of a multi-debris active removal mission with a partial debris capture strategy.A set of six pieces of debris and a set of 10 pieces of debris are selected to demonstrate the proposed planning method.The result confirms the effectiveness of the genetic algorithm with the multi-parameter concatenated coding method.The new mission model provides a more comprehensive decision-making framework than the existing mission models and makes it possible to further decrease mission costs.展开更多
Active debris removal(ADR) technology is an effective approach to remediate the proliferation of space debris, which seriously threatens the operational safety of orbital spacecraft. This study aims to design a contro...Active debris removal(ADR) technology is an effective approach to remediate the proliferation of space debris, which seriously threatens the operational safety of orbital spacecraft. This study aims to design a controller for a dual-arm space robot to capture tumbling debris, including capture control and detumbling control. Typical space debris is considered as a non-cooperative target, which has no specific capture points and unknown dynamic parameters. Compliant clamping control and the adaptive backstepping-based prescribed trajectory tracking control(PTTC)method are proposed in this paper. First, the differential geometry theory is utilized to establish the constraint equations, the dynamic model of the chaser-target system is obtained by applying the Hamilton variational principle, and the compliance clamping controller is further designed to capture the non-cooperative target without contact force feedback. Next, in the post-capture phase,an adaptive backstepping-based PTTC is proposed to detumble the combined spacecraft in the presence of model uncertainties. Finally, numerical simulations are carried out to validate the feasibility of the proposed capture and detumbling control method. Simulation results indicate that the target detumbling achieved by the PTTC method can reduce propellant consumption by up to24.11%.展开更多
A system combining granular activated carbon and powdered activated carbon technologies along with shortcut biological nitrogen removal (GAC-PACT-SBNR) was developed to enhance total nitrogen (TN) removal for anae...A system combining granular activated carbon and powdered activated carbon technologies along with shortcut biological nitrogen removal (GAC-PACT-SBNR) was developed to enhance total nitrogen (TN) removal for anaerobically treated coal gasification wastewater with less need for external carbon resources. The TN removal efficiency in SBNR was significantly improved by introducing the effluent from the GAC process into SBNR during the anoxic stage, with removal percentage increasing from 43.8%49.6% to 68.8%-75.8%. However, the TN removal rate decreased with the progressive deterioration of GAC adsorption. After adding activated sludge to the GAG compartment, the granular carbon had a longer service-life and the demand for external carbon resources became lower. Eventually, the TN removal rate in SBNR was almost constant at approx. 43.3%, as compared to approx. 20.0% before seeding with sludge. In addition, the production of some alkalinity during the denitrification resulted in a net savings in alkalinity requirements for the nitrification reaction and refractory chemical oxygen demand (COD) degradation by autotrophic bacteria in SBNR under oxic conditions. PACT showed excellent resilience to increasing organic loadings. The microbial community analysis revealed that the PACT had a greater variety of bacterial taxons and the dominant species associated with the three compartments were in good agreement with the removal of typical pollutants. The study demonstrated that pre-adsorption by the GAC-sludge process could be a technically and economically feasible method to enhance TN removal in coal gasification wastewater (CGW).展开更多
Space debris have become exceedingly dangerous over the years as the number of objects in orbit continues to increase.Active debris removal(ADR)missions have gained significant interest as effective means of mitigatin...Space debris have become exceedingly dangerous over the years as the number of objects in orbit continues to increase.Active debris removal(ADR)missions have gained significant interest as effective means of mitigating the risk of collision between objects in space.This study focuses on developing a multi-ADR mission that utilizes controlled reentry and deorbiting.The mission comprises two spacecraft:a Servicer that brings debris to a low altitude and a Shepherd that rendezvous with the debris to later perform a controlled reentry.A preliminary mission design tool(PMDT)was developed to obtain time and fuel optimal trajectories for the proposed mission while considering the effect of J2,drag,eclipses,and duty cycle.The PMDT can perform such trajectory optimizations for multi-debris missions with computational time under a minute.Three guidance schemes are also studied,taking the PMDT solution as a reference to validate the design methodology and provide guidance solutions to this complex mission profile.展开更多
This study involved simulations and experiments aimed at assessing the efficacy of a tether net in encapsulating space debris.The tether net was modeled as a spring–mass–damper system considering the influence of ae...This study involved simulations and experiments aimed at assessing the efficacy of a tether net in encapsulating space debris.The tether net was modeled as a spring–mass–damper system considering the influence of aerodynamic and gravitational forces and the occurrence of debris collisions.To examine the influence of collision position and size disparity between the debris and the net on debris capture status,the entanglement nodes of the net were identified.Experiments were conducted to evaluate the wrapping capabilities of the tether net,focusing specifically on debris capture.Subsequently,the results were compared with those of the numerical simulation.In the experiments,radio frequency identification was used to identify the entanglement points of the tether net.Previous studies have indicated that the ideal collision point for capturing debris using a tether net with the debris intended to be captured is located at the center of the net.However,the experimental results of this study revealed that a collision position that is slightly shifted from the center of the tether net is more advantageous for capturing debris in terms of tether net entanglement.展开更多
To control the growth of space debris in the geostationary earth orbit (GEO), a novel solution of net capture and tether-tugging reorbiting is proposed. After capture, the tug (i.e., active spacecraft), tether, ne...To control the growth of space debris in the geostationary earth orbit (GEO), a novel solution of net capture and tether-tugging reorbiting is proposed. After capture, the tug (i.e., active spacecraft), tether, net, and target (i.e., GEO debris) constitute a rig- id-flexible coupled tethered combination system (TCS), and subsequently the system is transported to the graveyard orbit by a thruster equipped on the tug. This paper attempts to study the dynamics of tether-tugging leorbiting after net capture. The net is equivalent to four flexible bridles, and the tug and target are viewed as rigid bodies. A sophisticated mathematical model is developed, taking into account the system orbital motion, relative motion of two spacecraft and spacecraft attitude motion. Given the complexity of the model, the numerical method is adopted to study the system dynamics characteristics. Particular attention is given to the investigation of the possible risks such as tether slack, spacecraft collision, tether rupture, tether-tug intertwist and destabilizing of the rug's attitude. The influence of the initial conditions and the magnitudes of the thrust are studied.展开更多
Objective: To investigate the efficacy and safety of the Chinese herbal therapeutic regimen of activating blood circulation (TRABC) in treatment of hypertensive intracerebral hemorrhage (HICH). Methods: This was...Objective: To investigate the efficacy and safety of the Chinese herbal therapeutic regimen of activating blood circulation (TRABC) in treatment of hypertensive intracerebral hemorrhage (HICH). Methods: This was a multi-center prospective randomized open-label blinded-endpoint (PROBE) trial with HICH admitted to 12 hospitals. Totally 240 participants were randomized to the treatment group treated with TRABC in addition to conventional Western treatment or the control group with conventional Western treatment equally for 3 months. Primary outcome was degree of disability as measured by modified Rankin Scale (mRS). Secondary outcomes were the absorption of hematoma and edema, National Institutes of Health Stroke Scale (NIHSS) scores and patient-reported outcome measures for stroke and Barthel activities of daily living index. Adverse events and mortality were also recorded. Results: After 3 months of treatment, the rate of mRS 0-1 and mRS 0-2 in the treatment group was 72.5% and 80.4%, respectively, and in the control group 48.1% and 63.9%, respectively, with a significant difference between groups (P〈0.01). Hematoma volume decreased significantly at day 7 of treatment in the treatment group than the control group (P=0.038). Average Barthel scores in the treatment group after treatment was 89.11 + 19.93, and in the control group 82.18 + 24.02 (P=0.003). NIHSS scores of the two groups after treatment decreased significantly compared with before treatment (P=0.001). Patient-reported outcomes in the treatment group were lower than the control group at day 21 and 3 months of treatment (P〈0.05). There were 4 deaths, 2 in each group, and 11 adverse events, 6 in the treatment group and 5 in the control group. Conclusion: The integrative therapy combined TRABC with conventional Western treatment for HICH could promote hematoma absorption thus minimize neurologic impairment, without increasing intracerebral hematoma expansion and re-bleeding.展开更多
Metastasis is one of the specificities of late stage tumor and also a lethal factor often encountered. The study of tumor metastasis has important meaning for prolonging patients' survival and elevating their quality...Metastasis is one of the specificities of late stage tumor and also a lethal factor often encountered. The study of tumor metastasis has important meaning for prolonging patients' survival and elevating their quality of life, but no really ideal prevention and treatment method has been found so far. Recent researches showed that tumor metastasis is correlated with platelet aggregation and blood hyperviscosity manner. Therefore, the early application of surgery, radiotherapy, chemotherapy and biological therapies, in combination with Chinese medicine therapy for activating blood circulation and removing stasis (ABCRS) may be, after all, an effective approach. ABCRS therapy is an important therapy of Chinese medicine, which, composed of several methods like smoothening blood flow in vessels, promoting blood circulation and dispersing stagnant blood, could influence tumor metastasis to different extents, and could coordinate with some other Chinese medicine therapeutic methods like supplementing qi, promoting qi, clearing heat, removing toxic substances, warming meridian, dispelling wind, eliminating dampness, nourishing yin, dissolving sputum, relieving stagnancy, emptying viscerals, etc. The effect and acting mechanism of ABCRS on tumor metastasis is summarized in this paper and its bi-directional regulatory effects discussed as well.展开更多
The therapeutic effects of activating blood circulation to remove stasis of Chinese medicine (CM) in the prevention and treatment of atherosclerotic diseases such as coronary artery disease and angina are generally ...The therapeutic effects of activating blood circulation to remove stasis of Chinese medicine (CM) in the prevention and treatment of atherosclerotic diseases such as coronary artery disease and angina are generally acknowledged. In recent years, to further improve the therapeutic effects of those Chinese herbs on such diseases, we have carried out a series of studies of CM medications with the function of clearing heat and removing toxic substances combined with activating blood circulation to remove stasis.展开更多
文摘AIM: To evaluate the efficacy and safety of active removal of silicone oil with low and high viscosity through a 23-gauge transconjunctival cannula using an external vacuum pump.METHODS: This study was conducted as a prospective, interventional case series. A total of 22 eyes of 21 patients [1000 centistokes(c St): 17 eyes, 5700 c St:5 eyes] were included in this study. All patients underwent active silicone oil removal via the entire lumen of a 23-gauge microcannula with suction pressure of a650-700 mm Hg vacuum using an external vacuum pump. A tubing adaptor from the Total Plus Pak誖(Alcon,Fort Worth, USA) was used to join the microcannula and silicone vacuum tube connected to an external vacuum pump. Main outcome measures were mean removal time,changes of intraocular pressure(IOP) and visual acuity,and intraoperative and postoperative complications.RESULTS: Mean removal time(min) was 1.49±0.43 for1000 c St and 7. 12 ± 1. 27 for 5700 c St. The IOP was18.57±7.48 mm Hg at baseline, 11.68 ±4.55 mm Hg at day1 postoperatively(P <0.001), and 15.95±4.92, 16.82±3.81,17.41 ±3.50, and 17.09 ±3.01 mm Hg after one week, one month, three months, and six months, respectively. All patients showed improved or stabilized visual acuity.There was no occurrence of intraoperative or postoperative complications during the follow up period.CONCLUSION: This technique for active removal of silicone oil through a 23-gauge cannula using an external vacuum pump is fast, effective, and safe as well as economical for silicone oil with both low and high viscosity in all eyes with pseudophakia, aphakia, or phakia.
基金the Open Research Foundation of Science and Technology in Aerospace Flight Dynamics Laboratory of China(GF2018005).
文摘Recent studies of the space debris environment in Low Earth Orbit(LEO)have shown that the critical density of space debris has been reached in certain regions.The Active Debris Removal(ADR)mission,to mitigate the space debris density and stabilize the space debris environment,has been considered as a most effective method.In this paper,a novel two-level optimization strategy for multi-debris removal mission in LEO is proposed,which includes the low-level and high-level optimization process.To improve the overall performance of the multi-debris active removal mission and obtain multiple Pareto-optimal solutions,the ADR mission is seen as a Time-Dependant Traveling Salesman Problem(TDTSP)with two objective functions to minimize the total mission duration and the total propellant consumption.The problem includes the sequence optimization to determine the sequence of removal of space debris and the transferring optimization to define the orbital maneuvers.Two optimization models for the two-level optimization strategy are built in solving the multi-debris removal mission,and the optimal Pareto solution is successfully obtained by using the non-dominated sorting genetic algorithm II(NSGA-II).Two test cases are presented,which show that the low level optimization strategy can successfully obtain the optimal sequences and the initial solution of the ADR mission and the high level optimization strategy can efficiently and robustly find the feasible optimal solution for long duration perturbed rendezvous problem.
基金Under the auspices of National Science Fund for Distinguished Young Scholars(No.51125035)National Science Foundation for Innovative Research Group(No.51121003)Major Science and Technology Program for Water Pollution Control and Treatment(No.2009ZX07209-008)
文摘Denitrification is an important process of nitrogen removal in lake ecosystems.However,the importance of denitrification across the entire soil-depth gradients including subsurface layers remains poorly understood.This study aims to determine the spatial pattern of soil denitrification enzyme activity(DEA) and its environmental determinants across the entire soil depth gradients in the raised fields in Baiyang Lake,North China.In two different zones of the raised fields(i.e.,water boundary vs.main body of the raised fields),the soil samples from 1.0 m to 1.1 m depth were collected,and the DEA and following environmental determinants were quantified:soil moisture,p H,total nitrogen(TN),ammonia nitrogen(NH4+-N),nitrate nitrogen(NO3–-N),total organic carbon(TOC),and rhizome biomass of Phragmites australis.The results showed that the soil DEA and environmental factors had a striking zonal distribution across the entire soil depth gradients.The soil DEA reached two peak values in the upper and middle soil layers,indicating that denitrification are important in both topsoil and subsurface of the raised fields.The correlation analysis showed that the DEA is negatively correlated with the soil depth(p < 0.05).However,this phenomenon did not occur in the distance to the water edge,except in the upper layers(from 0.2 m to 0.7 m) of the boundary zone of the raised fields.In the main body of the raised fields,the DEA level remained high;however,it showed no significant relationship with the distance to the water edge.The linear regression analysis showed significant positive correlation of the DEA with the soil TN,NO3–-N,NH4+-N,and TOC;whereas it showed negative correlation with soil p H.No significant correlations with soil moisture and temperature were observed.A positive correlation was also found between the DEA and rhizome biomass of P.australis.
基金Project supported by the National Natural Science Foundation of China(21271062)。
文摘In this study,hierarchical Ag/La2 O2 CO3 micro/nanostructures(MNSs)were synthesized by in situ loading Ag nanoparticles(NPs)on the surface of the La2 O2 CO3 MNSs.The prepared La2 O2 CO3 MNSs present flower-like shape and can be tuned by the molar ratio of La(NO3)3 and CO(NH2)2.In the molar ratio of 1:2 to 1:55,the La2 O2 CO3 MNSs mainly consist of polyhedral rods,irregular rods and irregular spindles and their size is about 10,8 and 7μm,respectively.After loading Ag NPs,the spindle-like Ag/La2 O2 CO3 MNSs were used for phosphate removal and antibacterial activity.At the initial phosphate concentration of20 mg/L,the removal rate is 59.6%.The Ag/La2 O2 CO3 MNSs have significant antibacterial activity and their MIC values for S.aureus and E.coli are 31.3 and 15.6μg/mL,respectively.The results indicate that Ag/La2 O2 CO3 MNSs may have good application prospects in open water to inhibit bacterial growth.
基金Supported by the National Nature Science Foundation(No.81473295)Science Technology project of Zhejiang Province(No.2014C33260)Wenzhou Science and Technology Bureau(No.Y20140142)
文摘AIM:To report a simple approach to actively remove high viscosity silicone oil through a 23-gauge cannula via pars plana.METHODS:Forty-eight eyes of 48 patients underwent silicone oil(5700 centistokes) removal(SOR) were enrolled.A section of blood transfusion set was prepared to connect a standard 23-gauge cannula and vitrectomy machine.Silicone oil was removed with suction of500-mm Hg vacuum through the cannula.Main outcome measures were SOR duration,number of sutured sites,intraocular pressure(IOP),best-corrected visual acuity(BCVA),and complications.RESULTS:Silicone oil was successfully removed in all cases.The mean SOR time was 5.70±0.85 min.Nine eyes(18.75%) needed suture partial sclerotomies.No intraoperative complications were noted.Transient hypotony(≤8 mm Hg) was seen in 3 eyes(6.25%) on postoperative day 1,but all resolved within 1wk.Retinal reattachment was achieved in all cases and no other postoperative complications were noted during 3-month following-up.BCVA at the final visit improved or stabilized in all patients comparing to the preoperative level.CONCLUSION:Active removal of high viscosity silicone oil through a 23-gauge instrument cannula jointed with blood transfusion set is a practical and reliable technique when considering two sides of efficacy and safety.
基金Supported by the National Nature Science Foundation of China No. 90209054
文摘Objective: To study the targeted point and mechanism of the function of the blood-activating and stasis-removing Chinese drugs, Paeoniae Radix 801(PR801) in its cardiovascular protective effects and its specific binding with endothelin 1(ET-1) as well as the dynamics of the two's interactive function by means of using affinity biosensors: IAsys Plus and quartz crystal microbalance (IAQCM). Methods: ET-1 was immobilized on the surfaces of IAQCM by using the new surface modification methods. The PR801 in the solution was detected by modified substrates and the specific binding between PR801 and ET-1 was studied. Results: The curves went up or down after adding PR801.There is specific binding between PR801 and ET-1. The bound mass were 0.458 ng/mm 2 and 133.54 ng/cm 2, respectively. There exists relatively good stability with these two methods. Conclusion: The affinity biosensors: IAQCM can be used to study the interaction mechanism between PR801 and ET-1, providing a new way to study the interaction mechanism of TCM. PR801 can bind ET-1 specifically in the experiments. Therefore, ET-1 is another target that PR801 can bind specifically besides thromboxane A 2.
文摘The treatment of hy-pertensive cerebral hemorrhage(HCH)by activatingblood circulation to removestasis(ABCRS)is a newtherapeutic approach,which is initiated by clinical specialists of TCM andintegrative Chinese andwestern medicine.Al-though it is not a flawless
基金Supported by National Natural Youth Science Foundation of China(81804106)。
文摘Studies have shown that traditional Chinese medicines have clear curative effects in the treatment of vitiligo with few side effects.Through literature research and clinical observation,the study summarized the etiology and pathogenesis of vitiligo in traditional Chinese medicine as"deficiency,toxin,and stasis",formulated the method of invigorating qi,promoting blood circulation and detoxification,and prescribed Fuse Hexue Jiawei Decoction for the treatment of vitiligo.
基金This work was supported by the National Key R&D Program of China(Grant No.2018YFB1304600)the National Natural Science Foundation of China(Grant No.51775541)+2 种基金the CAS Interdisciplinary Innovation Team(Grant No.JCTD-2018-11)the State Key Laboratory of Robotics Foundation(Grant No.Y91Z0303)the Hundred-Talent Program(Chinese Academy of Sciences)(Grant No.Y8A3210304).
文摘Space debris is growing dramatically with the rapid pace of human exploration of space,which seriously threatens the safety of artificial spacecraft in orbit.Therefore,the active debris removal(ADR)is important.This review aims to review the ADR methods and to advance related research in the future.The current research and development status are clearly demonstrated by mapping knowledge domain and charts.In this paper,the latest research results are classified and summarized in detail from two aspects of space debris capture and removal.The scheme comparison and evaluation of all ADR methods are performed,and the applicable scopes of various methods are summarized.Each ADR method is scored using a cobweb evaluation model based on six indicators.Future development of ADR is discussed to promote further research interest.
基金the National Natural Science Foundation of China(Magnetic Nanoparticles-based Cell Affinity Capillary Electrochromatography and Its Applications,No.21275169Screening of Bioactive Compounds From Typical Huoxue Huayu Medicine by Platelet Based Capillary Electrochromatography,No.81202886)+1 种基金the Fundamental Research Funds for the Central Universities(Study on the Quality Control Method for the Animal Glue Medicine,No.CQDXWL-2012-028)the Chongqing Postdoctoral Funds(No.RC20120027)
文摘OBJECTIVE: To evaluate the anti-platelet aggregation effects of extracts from 31 Traditional Chinese Medicines(TCM) with the property of activating blood and resolving stasis in terms of TCM theory.METHODS: The 31 TCMs extracts were prepared using water, 90% ethanol and ethyl acetate., and the effects on anti-platelet aggregation were tested on a platelet aggregation analyzer in vitro with adenosine 5'-diphosphate, bovine thrombin and arachi-donic acid(AA) as aggregation inducers, respectively. Aspirin was the positive control.RESULTS: Lots of the tested TCMs had inhibitory effects with concentration-dependent manner on platelet aggregations induced by various agonists.Especially, some of the TCMs such as Chuanxiong(Rhizoma Chuanxiong), Yanhusuo(Rhizoma Corydalis Yanhusuo) and Danshen(Radix Salviae Miltiorrhizae) showed good anti-platelet aggregation effect similar or higher than that in positive control group.CONCLUSION: The study provided scientific references that several TCMs such as Chuanxiong(Rhizoma Chuanxiong), Yanhusuo(Rhizoma Corydalis Yanhusuo) and Danshen(Radix Salviae Miltiorrhizae),possess the property of anti-platelet aggregation.
基金supported by US EPA STAR program(No.83517301)Missouri Department of Natural Resourcesthe support from Chemistry Department,Environmental Research Center,and Center for Single Nanoparticle,Single Cell,and Single Molecule Monitoring(CS3M)at Missouri University of Science and Technology
文摘When adding sufficient chlorine to achieve breakpoint chlorination to source water containing high concentration of ammonia during drinking water treatment, high concentrations of disinfection by-products(DBPs) may form. If N-nitrosamine precursors are present, highly toxic N-nitrosamines, primarily N-nitrosodimethylamine(NDMA), may also form. Removing their precursors before disinfection should be a more effective way to minimize these DBPs formation. In this study, zeolites and activated carbon were examined for ammonia and N-nitrosamine precursor removal when incorporated into drinking water treatment processes.The test results indicate that Mordenite zeolite can remove ammonia and five of seven N-nitrosamine precursors efficiently by single step adsorption test. The practical applicability was evaluated by simulation of typical drinking water treatment processes using six-gang stirring system. The Mordenite zeolite was applied at the steps of lime softening, alum coagulation, and alum coagulation with powdered activated carbon(PAC) sorption. While the lime softening process resulted in poor zeolite performance, alum coagulation did not impact ammonia and N-nitrosamine precursor removal. During alum coagulation, more than67% ammonia and 70%–100% N-nitrosamine precursors were removed by Mordenite zeolite(except 3-(dimethylaminomethyl)indole(DMAI) and 4-dimethylaminoantipyrine(DMAP)). PAC effectively removed DMAI and DMAP when added during alum coagulation. A combination of the zeolite and PAC selected efficiently removed ammonia and all tested seven N-nitrosamine precursors(dimethylamine(DMA), ethylmethylamine(EMA), diethylamine(DEA), dipropylamine(DPA), trimethylamine(TMA), DMAP, and DMAI) during the alum coagulation process.
基金co-supported by the Open Fund Project of Space Intelligent Control Technology Laboratory(No.HTKJ2021KL502010)the Research Project of Space Debris and Near-earth Asteroid Defense Grants,China(No.KJSP 2020010303)the National Natural Science Foundation of China(No.11802130).
文摘In this paper,a new mission model,called a multi-debris active removal mission with partial debris capture strategy,is proposed.The model assumes that a platform only captures part of the scheduled debris at a time and then releases these debris pieces to a disposal orbit.This process is then repeated until all of the scheduled debris is removed.A genetic algorithm with a multiparameter concatenated coding method is designed to optimize the plan of a multi-debris active removal mission with a partial debris capture strategy.A set of six pieces of debris and a set of 10 pieces of debris are selected to demonstrate the proposed planning method.The result confirms the effectiveness of the genetic algorithm with the multi-parameter concatenated coding method.The new mission model provides a more comprehensive decision-making framework than the existing mission models and makes it possible to further decrease mission costs.
基金supported by the National Natural Science Foundation of China(Nos.61725303 and 61803312)。
文摘Active debris removal(ADR) technology is an effective approach to remediate the proliferation of space debris, which seriously threatens the operational safety of orbital spacecraft. This study aims to design a controller for a dual-arm space robot to capture tumbling debris, including capture control and detumbling control. Typical space debris is considered as a non-cooperative target, which has no specific capture points and unknown dynamic parameters. Compliant clamping control and the adaptive backstepping-based prescribed trajectory tracking control(PTTC)method are proposed in this paper. First, the differential geometry theory is utilized to establish the constraint equations, the dynamic model of the chaser-target system is obtained by applying the Hamilton variational principle, and the compliance clamping controller is further designed to capture the non-cooperative target without contact force feedback. Next, in the post-capture phase,an adaptive backstepping-based PTTC is proposed to detumble the combined spacecraft in the presence of model uncertainties. Finally, numerical simulations are carried out to validate the feasibility of the proposed capture and detumbling control method. Simulation results indicate that the target detumbling achieved by the PTTC method can reduce propellant consumption by up to24.11%.
基金supported by Sino-Dutch Research Program (SDRP2011-2015)the independent subject sponsored by State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (No. 2013DX10)
文摘A system combining granular activated carbon and powdered activated carbon technologies along with shortcut biological nitrogen removal (GAC-PACT-SBNR) was developed to enhance total nitrogen (TN) removal for anaerobically treated coal gasification wastewater with less need for external carbon resources. The TN removal efficiency in SBNR was significantly improved by introducing the effluent from the GAC process into SBNR during the anoxic stage, with removal percentage increasing from 43.8%49.6% to 68.8%-75.8%. However, the TN removal rate decreased with the progressive deterioration of GAC adsorption. After adding activated sludge to the GAG compartment, the granular carbon had a longer service-life and the demand for external carbon resources became lower. Eventually, the TN removal rate in SBNR was almost constant at approx. 43.3%, as compared to approx. 20.0% before seeding with sludge. In addition, the production of some alkalinity during the denitrification resulted in a net savings in alkalinity requirements for the nitrification reaction and refractory chemical oxygen demand (COD) degradation by autotrophic bacteria in SBNR under oxic conditions. PACT showed excellent resilience to increasing organic loadings. The microbial community analysis revealed that the PACT had a greater variety of bacterial taxons and the dominant species associated with the three compartments were in good agreement with the removal of typical pollutants. The study demonstrated that pre-adsorption by the GAC-sludge process could be a technically and economically feasible method to enhance TN removal in coal gasification wastewater (CGW).
基金supported by the Ministry of Business,Innovation and Employment(MBIE)study:Astroscale/Rocket Lab/Te Punaha Atea-Space Institute Active Debris Removal Study。
文摘Space debris have become exceedingly dangerous over the years as the number of objects in orbit continues to increase.Active debris removal(ADR)missions have gained significant interest as effective means of mitigating the risk of collision between objects in space.This study focuses on developing a multi-ADR mission that utilizes controlled reentry and deorbiting.The mission comprises two spacecraft:a Servicer that brings debris to a low altitude and a Shepherd that rendezvous with the debris to later perform a controlled reentry.A preliminary mission design tool(PMDT)was developed to obtain time and fuel optimal trajectories for the proposed mission while considering the effect of J2,drag,eclipses,and duty cycle.The PMDT can perform such trajectory optimizations for multi-debris missions with computational time under a minute.Three guidance schemes are also studied,taking the PMDT solution as a reference to validate the design methodology and provide guidance solutions to this complex mission profile.
文摘This study involved simulations and experiments aimed at assessing the efficacy of a tether net in encapsulating space debris.The tether net was modeled as a spring–mass–damper system considering the influence of aerodynamic and gravitational forces and the occurrence of debris collisions.To examine the influence of collision position and size disparity between the debris and the net on debris capture status,the entanglement nodes of the net were identified.Experiments were conducted to evaluate the wrapping capabilities of the tether net,focusing specifically on debris capture.Subsequently,the results were compared with those of the numerical simulation.In the experiments,radio frequency identification was used to identify the entanglement points of the tether net.Previous studies have indicated that the ideal collision point for capturing debris using a tether net with the debris intended to be captured is located at the center of the net.However,the experimental results of this study revealed that a collision position that is slightly shifted from the center of the tether net is more advantageous for capturing debris in terms of tether net entanglement.
基金supported by the National Natural Science Foundation of China(Grant No.11272345)
文摘To control the growth of space debris in the geostationary earth orbit (GEO), a novel solution of net capture and tether-tugging reorbiting is proposed. After capture, the tug (i.e., active spacecraft), tether, net, and target (i.e., GEO debris) constitute a rig- id-flexible coupled tethered combination system (TCS), and subsequently the system is transported to the graveyard orbit by a thruster equipped on the tug. This paper attempts to study the dynamics of tether-tugging leorbiting after net capture. The net is equivalent to four flexible bridles, and the tug and target are viewed as rigid bodies. A sophisticated mathematical model is developed, taking into account the system orbital motion, relative motion of two spacecraft and spacecraft attitude motion. Given the complexity of the model, the numerical method is adopted to study the system dynamics characteristics. Particular attention is given to the investigation of the possible risks such as tether slack, spacecraft collision, tether rupture, tether-tug intertwist and destabilizing of the rug's attitude. The influence of the initial conditions and the magnitudes of the thrust are studied.
基金Supported by the Beijing Committee on Science and Technology,Project on Research on Two Standards of Traditional Chinese Medicine Treatment for Stroke(No.D101107049310003)
文摘Objective: To investigate the efficacy and safety of the Chinese herbal therapeutic regimen of activating blood circulation (TRABC) in treatment of hypertensive intracerebral hemorrhage (HICH). Methods: This was a multi-center prospective randomized open-label blinded-endpoint (PROBE) trial with HICH admitted to 12 hospitals. Totally 240 participants were randomized to the treatment group treated with TRABC in addition to conventional Western treatment or the control group with conventional Western treatment equally for 3 months. Primary outcome was degree of disability as measured by modified Rankin Scale (mRS). Secondary outcomes were the absorption of hematoma and edema, National Institutes of Health Stroke Scale (NIHSS) scores and patient-reported outcome measures for stroke and Barthel activities of daily living index. Adverse events and mortality were also recorded. Results: After 3 months of treatment, the rate of mRS 0-1 and mRS 0-2 in the treatment group was 72.5% and 80.4%, respectively, and in the control group 48.1% and 63.9%, respectively, with a significant difference between groups (P〈0.01). Hematoma volume decreased significantly at day 7 of treatment in the treatment group than the control group (P=0.038). Average Barthel scores in the treatment group after treatment was 89.11 + 19.93, and in the control group 82.18 + 24.02 (P=0.003). NIHSS scores of the two groups after treatment decreased significantly compared with before treatment (P=0.001). Patient-reported outcomes in the treatment group were lower than the control group at day 21 and 3 months of treatment (P〈0.05). There were 4 deaths, 2 in each group, and 11 adverse events, 6 in the treatment group and 5 in the control group. Conclusion: The integrative therapy combined TRABC with conventional Western treatment for HICH could promote hematoma absorption thus minimize neurologic impairment, without increasing intracerebral hematoma expansion and re-bleeding.
基金Supported by the 39th Post-doctoral Grant-funded Projects of China(No.20060390596)E-Institute Construction Plan Project of Shanghai Municipal Education Committee(No. E03008)
文摘Metastasis is one of the specificities of late stage tumor and also a lethal factor often encountered. The study of tumor metastasis has important meaning for prolonging patients' survival and elevating their quality of life, but no really ideal prevention and treatment method has been found so far. Recent researches showed that tumor metastasis is correlated with platelet aggregation and blood hyperviscosity manner. Therefore, the early application of surgery, radiotherapy, chemotherapy and biological therapies, in combination with Chinese medicine therapy for activating blood circulation and removing stasis (ABCRS) may be, after all, an effective approach. ABCRS therapy is an important therapy of Chinese medicine, which, composed of several methods like smoothening blood flow in vessels, promoting blood circulation and dispersing stagnant blood, could influence tumor metastasis to different extents, and could coordinate with some other Chinese medicine therapeutic methods like supplementing qi, promoting qi, clearing heat, removing toxic substances, warming meridian, dispelling wind, eliminating dampness, nourishing yin, dissolving sputum, relieving stagnancy, emptying viscerals, etc. The effect and acting mechanism of ABCRS on tumor metastasis is summarized in this paper and its bi-directional regulatory effects discussed as well.
文摘The therapeutic effects of activating blood circulation to remove stasis of Chinese medicine (CM) in the prevention and treatment of atherosclerotic diseases such as coronary artery disease and angina are generally acknowledged. In recent years, to further improve the therapeutic effects of those Chinese herbs on such diseases, we have carried out a series of studies of CM medications with the function of clearing heat and removing toxic substances combined with activating blood circulation to remove stasis.