The Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis,Pilleri&Gihr,1972;YFP)is an exclusively freshwater cetacean species inhabiting the Yangtze River and its connecting large lakes.As the prima...The Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis,Pilleri&Gihr,1972;YFP)is an exclusively freshwater cetacean species inhabiting the Yangtze River and its connecting large lakes.As the primary line of defense in maintaining physiological equilibrium,the epidermis of the porpoise is expected to have undergone structural adaptations due to the shift from the marine to the freshwater environment.This study compared the microstructural and ultrastructural features of the epidermis of YFP and its marine counterpart,the East Asian finless porpoise(Neophocaena asiaeorientalis sunameri,Pilleri&Gihr,1975;EAFP).Microscopic structural observations and statistical analyses of the epidermal thickness demonstrated no significant differences in the cell structure or distribution between the two porpoise species.However,the epidermis of the YFP contained more abundant stratum basale cells.The outermost lipid stratum corneum exhibited a thinner cell layer with wider neutral lipid droplets to resist the passive entry of water molecules in the hypotonic environment.In contrast,for the EAFp,a more uniformly arranged stratum basale in the epidermis led to denser keratin fibers and robust desmosomes within each epidermal layer at the ultrastructural level.This tight arrangement of cells can reduce transepidermal water loss(TEWL)in an environment with higher osmotic pressure.In conclusion,the 2 finless porpoise species appear to employ different epidermal mechanisms to adapt to their distinct osmotic environments.The YFP appears to possess a"lipid waterproofing"epidermal structure,while the EAFP possesses a"thick and compact water-retaining"epidermal structure to copewithpotentialwaterloss.展开更多
Harvesting the immense and renewable osmotic energy with reverse electrodialysis(RED)technology shows great promise in dealing with the ever-growing energy crisis.One key challenge is to improve the output power densi...Harvesting the immense and renewable osmotic energy with reverse electrodialysis(RED)technology shows great promise in dealing with the ever-growing energy crisis.One key challenge is to improve the output power density with improved trade-off between membrane permeability and selectivity.Herein,polyelectrolyte hydrogels(channel width,2.2 nm)with inherent high ion conductivity have been demonstrated to enable excellent selective ion transfer when confined in cylindrical anodized aluminum pore with lateral size even up to the submillimeter scale(radius,0.1 mm).The membrane permeability of the anti-swelling hydrogel can also be further increased with cellulose nanofibers.With real seawater and river water,the output power density of a three-chamber cell on behalf of repeat unit of RED system can reach up to 8.99 W m^(-2)(per unit total membrane area),much better than state-of-the-art membranes.This work provides a new strategy for the preparation of polyelectrolyte hydrogel-based ion-selective membranes,owning broad application prospects in the fields of osmotic energy collection,electrodialysis,flow battery and so on.展开更多
With the global advancement of the circular economy,integrating reverse osmosis(RO)or forward osmosis(FO)with anaerobic membrane bioreactor(AnMBR)offers a promising approach to simultaneously generate high-grade recla...With the global advancement of the circular economy,integrating reverse osmosis(RO)or forward osmosis(FO)with anaerobic membrane bioreactor(AnMBR)offers a promising approach to simultaneously generate high-grade reclaimed water,produce energy,and preserve valuable nutrients from municipal wastewater.However,the selectivity of these osmotic membranes towards ammonia nitrogen,a major component in municipal wastewater and anaerobic effluent,remains unsatisfactory due to its similar polarity and hydraulic radius to water molecules.Therefore,enhancing the ammonia nitrogen rejection of osmotic membranes is imperative to maximize the quality of reclaimed water and minimize the loss of ammonia nitrogen resources.Unfortunately,the current understanding of the mapping relationship between ammonia nitrogen transmembrane diffusion and the micro/nano-structure of osmotic membranes is not systematic,making precise optimization of the membranes challenging.Hence,this review comprehensively analyzed the diffusion behavior of ammonia nitrogen through osmotic membranes to lay the foundation for targeted regulation of membrane fine structure.Initially,the desire for ammonia/ammonium-rejecting membranes was highlighted by introducing current and promising osmotic membrane-based applications in municipal wastewater reclamation processes.Subsequently,the connection between the micro/nano-structure of osmotic membranes and the transmembrane diffusion behavior of ammonia nitrogen was explored by analyzing the effects of membrane characteristics on ammonia nitrogen transport using the DSPM-DE model.Finally,precise methods for modifying membranes to enhance ammonia nitrogen rejection were proposed.This review aims to offer theoretical insights guiding the development of RO and FO membranes with superior ammonia nitrogen rejection for efficient reclamation of municipal wastewater.展开更多
Cronobacter spp.has strong resistance to desiccation and high permeability in Enterobacteriaceae,and powdered infant formula(PIF)is one of the main contamination routes.In recent years,the contamination of Cronobacter...Cronobacter spp.has strong resistance to desiccation and high permeability in Enterobacteriaceae,and powdered infant formula(PIF)is one of the main contamination routes.In recent years,the contamination of Cronobacter spp.in PIF incidents occurs from time to time,causing infant serious diseases or death.In this investigation,matrix-assisted laser desorption/ionization time of flight mass spectrometry was used to identify the phenotypes of 35 Cronobacter strains isolated from PIF and its processing environment.Subsequently,the isolates were evaluated for drying and osmotic pressure tolerance.The results showed that the deactivation rate of the strains ranged from 9.01%to 77.57%,and the highest osmotic pressure condition the strains could tolerate was 6 g/100 mL Na Cl.In addition,there was a positive correlation between biofilm formation ability and desiccation resistance.Combined with transcriptomics,Cronobacter spp.could activate biofilm synthesis,produce more trehalose,accumulate betaine and electrolytes to stabilize intracellular structure under the two treatment conditions.A total of 31 and 43 genes were found related to desiccation and permeability resistance,respectively.And some genes(cysM,thuF,ycjO,etc.)were found to be associated with two tolerances for the first time.展开更多
As space technology advances,thermal control systems must effectively collect and dissipate heat from distributed,multi-source environments.Loop heat pipe is a highly reliable two-phase heat transfer component,but it ...As space technology advances,thermal control systems must effectively collect and dissipate heat from distributed,multi-source environments.Loop heat pipe is a highly reliable two-phase heat transfer component,but it has several limitations when addressing multi-source heat dissipation.Inspired by the transport and heat dissipation system of plants,large trees achieve stable and efficient liquid supply under the influence of two driving forces:capillary force during transpiration in the leaves(pull)and root pressure generated by osmotic pressure in the roots(push).The root pressure provides an effective liquid supply with a driving force exceeding 2 MPa,far greater than the driving force in conventional capillary-pumped two-phase loops.Research has shown that osmotic heat pipes offer a powerful driving force,and combining osmotic pressure with capillary force has significant advantages.Therefore,this paper designs a multi-evaporator,dual-drive two-phase loop,using both osmotic pressure and capillary force to solve the multi-source heat dissipation challenge.First,a transmembrane water flux model for the osmotic pressure-driven device was established to predict the maximum heat transfer capacity of the dual-drive two-phase loop.Then,an experimental setup for a multi-evaporator“osmotic pressure+capillary force”dual-drive two-phase loop was constructed,capable of transferring at least 235 W of power under a reverse gravity condition of 20 m.The study also analyzed the effects of reverse gravity height,heat load distribution among the three evaporators,startup sequence,and varying branch resistances on the performance of the dual-drive two-phase loop.展开更多
Nanofluidic channels inspired by electric eels open a new era of efficient harvesting of clean blue osmotic energy from salinity gradients.Limited by less charge and weak ion selectivity of the raw material itself,ene...Nanofluidic channels inspired by electric eels open a new era of efficient harvesting of clean blue osmotic energy from salinity gradients.Limited by less charge and weak ion selectivity of the raw material itself,energy conversion through nanofluidic channels is still facing considerable challenges.Here,a facile and efficient strategy to enhance osmotic energy harvesting based on drastically increasing surface charge density of MXenes subnanochannels via oxygen plasma is proposed.This plasma could break Ti–C bonds in the MXenes subnanochannels and effectively facilitate the formation of more Ti–O,C═O,O–OH,and rutile with a stronger negative charge and work function,which leads the surface potential of MXenes membrane to increase from 205 to 430 mV.This significant rise of surface charge endows the MXenes membrane with high cation selectivity,which could make the output power density of the MXenes membrane increase by 248.2%,reaching a high value of 5.92Wm^(−2) in the artificial sea‐river water system.Furthermore,with the assistance of low‐quality heat at 50℃,the osmotic power is enhanced to an ultrahigh value of 9.68Wm^(−2),which outperforms those of the state‐of‐the‐art two‐dimensional(2D)nanochannel membranes.This exciting breakthrough demonstrates the enormous potential of the facile plasma‐treated 2D membranes for osmotic energy harvesting.展开更多
Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drou...Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple(Malus×domestica Borkh.)remain unclear.Here,we functionally characterized the apple GroupⅢWRKY gene MdWRKY115.qRT-PCR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic stresses.GUS activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic stress.Subcellular localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal region.Transgenic analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic stresses.DNA affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene MdRD22.This binding was further verified by an electrophoretic mobility shift assay.Collectively,these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple.展开更多
Osmotic stress caused by low-temperature,drought and salinity was a prevalent abiotic stress in plant that severely inhibited plant development and agricultural yield,particularly in tea plant.Jasmonic acid(JA)is an i...Osmotic stress caused by low-temperature,drought and salinity was a prevalent abiotic stress in plant that severely inhibited plant development and agricultural yield,particularly in tea plant.Jasmonic acid(JA)is an important phytohormone involving in plant stress.However,underlying molecular mechanisms of JA modulated osmotic stress response remains unclear.In this study,high concentration of mannitol induced JA accumulation and increase of peroxidase activity in tea plant.Integrated transcriptome mined a JA signaling master,MYC2 transcription factor is shown as a hub regulator that induced by mannitol,expression of which positively correlated with JA biosynthetic genes(LOX and AOS)and peroxidase genes(PER).CsMYC2 was determined as a nuclei-localized transcription activator,furthermore,ProteinDNA interaction analysis indicated that CsMYC2 was positive regulator that activated the transcription of CsLOX7,CsAOS2,CsPER1 and CsPER3via bound with their promoters,respectively.Suppression of CsMYC2 expression resulted in a reduced JA content and peroxidase activity and osmotic stress tolerance of tea plant.Overexpression of CsMYC2 in Arabidopsis improved JA content,peroxidase activity and plants tolerance against mannitol stress.Together,we proposed a positive feedback loop mediated by CsMYC2,CsLOX7 and CsAOS2 which constituted to increase the tolerance of osmotic stress through fine-tuning the accumulation of JA levels and increase of POD activity in tea plant.展开更多
SubclassⅢsucrose nonfermenting1-related protein kinase 2s(SnRK2s)function in ABA and abiotic stress responses by unknown mechanisms.We found that osmotic stress/ABA-activated protein kinase 10(SAPK10),a member of ric...SubclassⅢsucrose nonfermenting1-related protein kinase 2s(SnRK2s)function in ABA and abiotic stress responses by unknown mechanisms.We found that osmotic stress/ABA-activated protein kinase 10(SAPK10),a member of rice SnRK2s,physically interacted with CBL-interacting protein kinase 1(OsCIPK1).OsCIPK1 expression was up-regulated by ABA and PEG treatment,and overexpression increased the ABA sensitivity of seed germination and root growth and plant osmotic stress tolerance.Osmotic stress or ABA-induced activation of OsCIPK1 is dependent on SAPK10.SAPK10 phosphorylates Thr-24 of OsCIPK1 in vitro,and this phosphorylation increases the activity of OsCIPK1 and positively regulates the function of OsCIPK1 in ABA responses and plant osmotic stress tolerance.This study suggests that OsCIPK1 is a direct phosphorylated substrate of SAPK10,and SAPK10-mediated phosphorylation of OsCIPK1 functions in ABA signaling and increases rice osmotic stress tolerance.展开更多
Following large-scale volume fracturing in shale oil reservoirs,well shut-in measures are generally employed.Laboratory tests and field trials have underscored the efficacy of fracturing fluid imbibition during the sh...Following large-scale volume fracturing in shale oil reservoirs,well shut-in measures are generally employed.Laboratory tests and field trials have underscored the efficacy of fracturing fluid imbibition during the shut-in phase in augmenting shale oil productivity.Unlike conventional reservoirs,shale oil reservoirs exhibit characteristics such as low porosity,low permeability,and rich content of organic matter and clay minerals.Notably,the osmotic pressure effects occurring between high-salinity formation water and low-salinity fracturing fluids are significant.The current understanding of the mobilization patterns of crude oil in micro-pores during the imbibition process remains nebulous,and the mechanisms underpinning osmotic pressure effects are not fully understood.This study introduces a theoretical approach,by which a salt ion migration control equation is derived and a mathematical model for spontaneous imbibition in shale is introduced,which is able to account for both capillary and osmotic pressures.Results indicate that during the spontaneous imbibition of low-salinity fluids,osmotic effects facilitate the migration of external fluids into shale pores,thereby complementing capillary forces in displacing shale oil.When considering both capillary and osmotic pressures,the calculated imbibition depth increases by 12%compared to the case where only capillary forces are present.The salinity difference between the reservoir and the fracturing fluids significantly influences the imbibition depth.Calculations for the shutin phase reveal that the pressure between the matrix and fractures reaches a dynamic equilibrium after 28 days of shut-in.During the production phase,the maximum seepage distance in the target block is approximately 6.02 m.展开更多
Lappaconitine is a water-insoluble drug, which was used as model drug in this study. Currently, two osmotically controlled delivery systems that are widely used for water-insoluble drug are monolithic osmotic tablet ...Lappaconitine is a water-insoluble drug, which was used as model drug in this study. Currently, two osmotically controlled delivery systems that are widely used for water-insoluble drug are monolithic osmotic tablet （MOT） and push-pull osmotic pump （PPOP）. In the present study, lappaconitine solid dispersion monolithic osmotic tablet （lappaconitine-SD-MOT） and lappaconitine-PPOP were developed. The prepared lappaconitine-PPOP was able to delivery drug at the rate of approximate zero-order （r = 0.9931）, and the cumulative release was above 95.0%. The lappaconitine-SD-MOT showed a comparatively poor linearity when the data were plotted according to the zero-order equation （r = 0.9798）, and the cumulative release was 84.69%. Lappaconitine-PPOP exhibited better controlled drug release （higher regression value） compared with lappaconitine-SD-MOT. The similarity index （f2） between lappaconitine-PPOP and lappaconitine-SD-MOT was 49.1 （〈50）. A clear difference of drug release characteristics between the lappaconitine-SD-MOT and lappaconitine-PPOP was revealed. It indicated that the drug release performance of lappaconitine-PPOP could gain favorable zero-order kinetics and higher cumulative release compared with lappaconitine-SD-MOT. Therefore, these results suggested that PPOP was still a very effective device for the delivery of poorly water-soluble drug with zero-order pattern.展开更多
[ Objective] The purpose was to discuss drought resistance mechanism of Chenopodium album L. and supply theoretical basis and practical guidance for artificial cultivation and popularization of C. album. [ Method] C. ...[ Objective] The purpose was to discuss drought resistance mechanism of Chenopodium album L. and supply theoretical basis and practical guidance for artificial cultivation and popularization of C. album. [ Method] C. album seedlings grown to 6th leaf stage were conducted osmotic stress treatment with PEG6000 osmotic whose concentration was set up as 0, 5%, 10% and 20% and the various physiological indices of the 3rd -5th function leaves in upper plant were determined after being treated for 0, 1,3, 5, 7 and 9 d. [ Result] Under osmotic stress with 5% PGE, the relative water content （RWC） of C. album reduced less. Under osmotic stress with 10%, the RWC in seedling leaves of C. album decreased to 62% on the fifth day and the leaves began to wither. Under osmotic stress with 20%, the RWC in seedling leaves of C. album decreased to 61.9% on the third day and the leaves appeared withering, and the RWC decreased to 48.6% on the 7th day and the leaves were dry and yellow. Proline contents in seedling leaves of C. album under osmotic stress with 5%, 10% and 20% PEG were 7.64, 10.9 and 29.4 times of CK on the 7th day. [ Conclusion] C. album hed some adaptability to moderate osmotic stress, but the PEG osmotic stress with high concentration and long time might lead to severe damage on C. album.展开更多
Effects of sodium nitroprusside (SNP), a nitric oxide (NO) donor, on the germination and metabolism of reactive oxygen species were surveyed in wheat (Triticum aestivum L.) seeds. Germination of wheat seeds and even t...Effects of sodium nitroprusside (SNP), a nitric oxide (NO) donor, on the germination and metabolism of reactive oxygen species were surveyed in wheat (Triticum aestivum L.) seeds. Germination of wheat seeds and even the elongation of radicle and plumule were dramatically promoted by SNP treatments during the germination under osmotic stress. Meanwhile, activities of amylase and EP were enhanced, thus leading to the degradation of storage reserve in seeds. After osmotic stress was removed, higher viability of wheat seeds was also maintained. In addition, the activities of CAT, APX and the content of proline were increased by SNP treatment simultaneously, but activities of LOX were inhibited, and both of which were beneficial for improving the antioxidant capacity during the germination of wheat seeds under osmotic stress. It was also shown that the increase of the activity of amylase induced by SNP in embryoless half-seeds of wheat in the beginning period of germination (6 h) might be indirectly related to GA(3).展开更多
[Objective]The research aimed to probe into the mechanism of polyamine enhancing the tolerance of plants to drought stress and provide theoretical basis for application of polyamine in process of maize drought resista...[Objective]The research aimed to probe into the mechanism of polyamine enhancing the tolerance of plants to drought stress and provide theoretical basis for application of polyamine in process of maize drought resistance. [Method]With PEG-6000 simulating natural drought,the change in content of soluble protein and relative water content were investigated in seedling leaves of two maize cultivars,Nongda 108 and Yedan 13 under osmotic stress with exogenous Spd treatment. [Result]On the 7th day,leaf relative water content and the content of soluble protein decreased more significantly in leaves of Yedan 13 （drought-sensitive） than in Nongda 108 （drought-tolerant）. Exogenous Spd treatment not only obviously inhibited the decrease of leaf relative water content,but also increased the content of soluble protein. [Conclusion]Exogenous Spd treatment could enhance the tolerance of maize seedlings to osmotic stress,via improving the content of soluble protein in seedling leaves.展开更多
The objective of this study was to prepare monolithic osmotic tablet of quercetin for controlled drug release. Quercetin-PVP solid dispersion was prepared to enhance its solubility and dissolution rate. Solid dispersi...The objective of this study was to prepare monolithic osmotic tablet of quercetin for controlled drug release. Quercetin-PVP solid dispersion was prepared to enhance its solubility and dissolution rate. Solid dispersion, suspending agents, osmotic agents and other conventional excipients were used as tablet core composition and cellulose acetate （CA） with plasticizer as release controlling membrane. Different formulation variables, the amounts of PEO （polyethylene oxide）, NaC1, plasticizer, and coating weight gain were optimized to gain the optimum formulation. The mechanism of drug release from monolithic osmotic tablet was also discussed. The optimal monolithic osmotic pump tablet could deliver quercetin at the rate of approximate zero-order up to 12 h, and the cumulative release was 90.74%. The developed monolithic osmotic system for quercetin loaded by solid dispersion was found to be a promising approach for controlled release of poorly-water soluble drug candidates.展开更多
[Objective] This study aimed to investigate the effects of drought stress on osmotic regulation substances of Catalpa bungei clones. [Method] Potting experimental was carried out with plastic film sealing method, to d...[Objective] This study aimed to investigate the effects of drought stress on osmotic regulation substances of Catalpa bungei clones. [Method] Potting experimental was carried out with plastic film sealing method, to differentiate the degrees of drought stress based on changes in soil water content and leaf water potential and investigate variations in contents of osmotic regulation substances（free proline,soluble sugar and soluble protein） in leaves of five Catalpa bungei clones under different degrees of drought stresses. [Result] According to changes in soil water content and leaf water potential, the whole process of drought stress was divided into normal level（CK, with soil water content of 97.49% and leaf water potential of-0.54MPa）, light drought（LD with soil water content of 59.96% and leaf water potential of-1.28 MPa）, mediate drought（MD with soil water content of 34.19% and leaf water potential of-2.32 MPa） and severe drought（SD with soil water content of 14.52%and leaf water potential of-2.99 MPa）. The soil water content and leaf water potential of five Catalpa bungei clones reached the highest correlation in exponential fitting, with an average R2of 0.989 3（P0.001）. The free proline content in leaves of five Catalpa bungei clones increased rapidly with the increasing degree of drought stress（P 0.001）. To be specific, free proline contents of Catalpa bungei clones015-1 and 7080 were 34.39 and 33.41 times of the normal level under severe drought conditions, which reached an extremely significant level（P0.001）; the free proline content of Catalpa bungei clone 1-3 rapidly increased to（855.46±227.52） μg/g Fw under light drought conditions. The soluble protein content in leaves showed different variation trends. To be specific, the soluble protein content of Catalpa bungei clone 7080 was the lowest at various drought stages and reached（1.644 ±0.137）mg/g Fw under normal conditions; the soluble protein content of Catalpa bungei clone 1-3 was relatively high under normal conditions and was reduced rapidly under light drought conditions, showing different response patterns. [Conclusion] Osmotic regulation substances in leaves of five Catalpa bungei clones all have certain response to drought stress. Free proline is the most important osmotic regulation substance, followed by soluble protein, while soluble sugar makes no significant contribution. According to changes in content of osmotic regulation substances, Catalpa bungei clone 7080 has relatively high capacity and good drought resistance, while Catalpa bungei clone 1-3 has the rapidest response to drought stress.展开更多
Four rice ( Oryza sativa L.) cultivars 'IR72', 'Tesanai 2', 'Guichao 2' and 'IIyou 4480' were grown in two plastic house (15 m×3 m) with 35 μmol/mol and 60 μmol/mol CO 2 conc...Four rice ( Oryza sativa L.) cultivars 'IR72', 'Tesanai 2', 'Guichao 2' and 'IIyou 4480' were grown in two plastic house (15 m×3 m) with 35 μmol/mol and 60 μmol/mol CO 2 concentration which was controlled by computer. As compared with rice at ambient 35 μmol/mol CO 2, the changes in photosynthetic rate at elevated CO 2 showed up_regulation ('IR72' and 'Tesanai 2'), stable (unchanged) in 'Guichao 2' and down_regulation type ('IIyou 4480'). Growth rate, panicle weight, integrated water use efficiency (WUE) calculated from Δ 13 C and the capacity of scavenging DPPH · (1,1_diphenyl_2_picrylhydrazyl) free radical were increased at elevated CO 2. An increment in total biomass was observed in three cultivars by elevated CO 2, with the exception of 'IIyou 4480'. Ratios of panicle weight/total biomass were altered to different extents in tested cultivars by elevated CO 2. When leaf segments were subjected to PEG osmotic stress, the electrolyte leakage rate from leaves grown at elevated CO 2 was less than that at 35 μmol/mol CO 2. Those intraspecific variations of rice imply a possibility for selecting cultivars with maximal productivity and high tolerance to stresses adapted to elevated CO 2 in the future.展开更多
In previous studies, compound mefformin/glipizide was developed. Aim To discover the mechanism of drug release from factors influencing drug release from dosage form （the semi-permeable cry orifice） were investigate...In previous studies, compound mefformin/glipizide was developed. Aim To discover the mechanism of drug release from factors influencing drug release from dosage form （the semi-permeable cry orifice） were investigated. Results The influx of water that elementary osmotic pump tablet it. Methods Three rate-limiting membrane, tablet core and delivpassed the osmotic pump tablet was almost equal to the metformin release rate, while it was greatly less than the drug dissolution rate from tablet core. The size of orifice from 0. 4 mm to 0.8 mm had no influence on drug release. The osmotic pressure of tablet core was mainly caused by mefformin. Conclusion From the developed model of osmotic pump systems, it can be seen that only the water influx through the membrane is a rate-limiting step, not tablet core dissolution rate and solution influx, and only when the core dissolution rate is equal to the solution influx, the zero order release is seen in the osmotic pump systems.展开更多
With light and electron microscopy the substructural change and the ATPase activity of corn (Zea mays L.) root cap cells after short-term osmotic stress were studied. Some spoke-like fine strands originating from the ...With light and electron microscopy the substructural change and the ATPase activity of corn (Zea mays L.) root cap cells after short-term osmotic stress were studied. Some spoke-like fine strands originating from the departed periplasm and stretching towards cell wall could be observed even after plasmolysis. By observing the precipitation of ATPase activity product (lead phosphate) at plasma membrane and plasmodesmata, it was found that the fine strands were plasma membrane-lined channels surrounding the cytoplasm and that they still firmly connected to the plasmodesmata during plasmolysis. Compared with the control (unstressed), a sharp decrease of ATPase activity in the plasmodesmata of the stressed cells was observed. Inhibition of energy metabolism in these limited locales would affect the physiological activity, maybe including the regulation of permeability and the change of size exclusion limit (SEL) of plasmodesmata.展开更多
The clinical pharmacokinetics of osmotic pump controlled release tablets of terazosin hydrochloride in healthy volunteers was studied.A sensitive and rapid HPLC method was used to determine the terazosin plasma concen...The clinical pharmacokinetics of osmotic pump controlled release tablets of terazosin hydrochloride in healthy volunteers was studied.A sensitive and rapid HPLC method was used to determine the terazosin plasma concentrations,and single and multiple doses of terazosin hydrochloride regular tablets（reference tablets）and osmotic pump controlled release tablets were orally administrated in randomized crossover design.The results showed that the C_（max）of the reference tablets after single oral dose（（120.56±23.15）ng/mL）in 20 healthy volunteers was significantly higher than that of controlled release tablets （（95.27±16.35）ng/mL）.The T_（max）of the controlled release tablets（（2.65±0.82）h）was significantly longer than that of reference tablets（（1.27±0.61）h）（P0.05）.The relative bioavailability of the controlled release tablets was found to be（105.85±6.12）%. The multiple oral dose pharmacokinetic parameters of the regular tablets and controlled release tablets were as follows：AUC_（SS） were（1275.17±175.35）and（1382.65±205.31）ng·h/mL respectively,C_（max）were（128.15±22.37）and（98.57±18.16）ng/mL respectively,T_（max）were（1.35±0.71）and（2.76±0.85）h respectively,C_（av）were（53.13±9.12）and（57.61±9.25）ng/mL respectively, and DF were（2.25±0.26）%and（1.62±0.25）%respectively.The relative bioavailability of the controlled release tablets to the reference tablets was（108.43±6.26）%.The controlled release tablet of terazosin hydrochloride was bioequivalent to the reference tablet.The controlled release tablet exhibited a sustained-release property with a significantly longer T_（max）and lower C_（max）.展开更多
基金supported by the National Key R&D Program of China(2021YFD1200304).
文摘The Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis,Pilleri&Gihr,1972;YFP)is an exclusively freshwater cetacean species inhabiting the Yangtze River and its connecting large lakes.As the primary line of defense in maintaining physiological equilibrium,the epidermis of the porpoise is expected to have undergone structural adaptations due to the shift from the marine to the freshwater environment.This study compared the microstructural and ultrastructural features of the epidermis of YFP and its marine counterpart,the East Asian finless porpoise(Neophocaena asiaeorientalis sunameri,Pilleri&Gihr,1975;EAFP).Microscopic structural observations and statistical analyses of the epidermal thickness demonstrated no significant differences in the cell structure or distribution between the two porpoise species.However,the epidermis of the YFP contained more abundant stratum basale cells.The outermost lipid stratum corneum exhibited a thinner cell layer with wider neutral lipid droplets to resist the passive entry of water molecules in the hypotonic environment.In contrast,for the EAFp,a more uniformly arranged stratum basale in the epidermis led to denser keratin fibers and robust desmosomes within each epidermal layer at the ultrastructural level.This tight arrangement of cells can reduce transepidermal water loss(TEWL)in an environment with higher osmotic pressure.In conclusion,the 2 finless porpoise species appear to employ different epidermal mechanisms to adapt to their distinct osmotic environments.The YFP appears to possess a"lipid waterproofing"epidermal structure,while the EAFP possesses a"thick and compact water-retaining"epidermal structure to copewithpotentialwaterloss.
基金supported by The Project of“20 Items of University”of Jinan(Grant No.202228078)Innovative Research Team in Higher Educational Institutions of Shandong Province(Grant No.2023KJ107)+2 种基金Taishan Scholars Program of Shandong Province(tsqn201812085)National Natural Science Foundation of China(Grant No.51903102,Grant No.52376063,Grant No.52302256)China Postdoctoral Science Foundation(Grant No.2023MD744223).
文摘Harvesting the immense and renewable osmotic energy with reverse electrodialysis(RED)technology shows great promise in dealing with the ever-growing energy crisis.One key challenge is to improve the output power density with improved trade-off between membrane permeability and selectivity.Herein,polyelectrolyte hydrogels(channel width,2.2 nm)with inherent high ion conductivity have been demonstrated to enable excellent selective ion transfer when confined in cylindrical anodized aluminum pore with lateral size even up to the submillimeter scale(radius,0.1 mm).The membrane permeability of the anti-swelling hydrogel can also be further increased with cellulose nanofibers.With real seawater and river water,the output power density of a three-chamber cell on behalf of repeat unit of RED system can reach up to 8.99 W m^(-2)(per unit total membrane area),much better than state-of-the-art membranes.This work provides a new strategy for the preparation of polyelectrolyte hydrogel-based ion-selective membranes,owning broad application prospects in the fields of osmotic energy collection,electrodialysis,flow battery and so on.
基金supported by National Natural Science Foundation of China(No.52200051)Harbin Institute of Technology(No.HC202236)Outstanding Youth Fund of Heilongjiang Natural Science Foundation(No.YQ2023E021)。
文摘With the global advancement of the circular economy,integrating reverse osmosis(RO)or forward osmosis(FO)with anaerobic membrane bioreactor(AnMBR)offers a promising approach to simultaneously generate high-grade reclaimed water,produce energy,and preserve valuable nutrients from municipal wastewater.However,the selectivity of these osmotic membranes towards ammonia nitrogen,a major component in municipal wastewater and anaerobic effluent,remains unsatisfactory due to its similar polarity and hydraulic radius to water molecules.Therefore,enhancing the ammonia nitrogen rejection of osmotic membranes is imperative to maximize the quality of reclaimed water and minimize the loss of ammonia nitrogen resources.Unfortunately,the current understanding of the mapping relationship between ammonia nitrogen transmembrane diffusion and the micro/nano-structure of osmotic membranes is not systematic,making precise optimization of the membranes challenging.Hence,this review comprehensively analyzed the diffusion behavior of ammonia nitrogen through osmotic membranes to lay the foundation for targeted regulation of membrane fine structure.Initially,the desire for ammonia/ammonium-rejecting membranes was highlighted by introducing current and promising osmotic membrane-based applications in municipal wastewater reclamation processes.Subsequently,the connection between the micro/nano-structure of osmotic membranes and the transmembrane diffusion behavior of ammonia nitrogen was explored by analyzing the effects of membrane characteristics on ammonia nitrogen transport using the DSPM-DE model.Finally,precise methods for modifying membranes to enhance ammonia nitrogen rejection were proposed.This review aims to offer theoretical insights guiding the development of RO and FO membranes with superior ammonia nitrogen rejection for efficient reclamation of municipal wastewater.
基金supported by the Joint Funds of the National Natural Science Foundation of China(U21A20272)。
文摘Cronobacter spp.has strong resistance to desiccation and high permeability in Enterobacteriaceae,and powdered infant formula(PIF)is one of the main contamination routes.In recent years,the contamination of Cronobacter spp.in PIF incidents occurs from time to time,causing infant serious diseases or death.In this investigation,matrix-assisted laser desorption/ionization time of flight mass spectrometry was used to identify the phenotypes of 35 Cronobacter strains isolated from PIF and its processing environment.Subsequently,the isolates were evaluated for drying and osmotic pressure tolerance.The results showed that the deactivation rate of the strains ranged from 9.01%to 77.57%,and the highest osmotic pressure condition the strains could tolerate was 6 g/100 mL Na Cl.In addition,there was a positive correlation between biofilm formation ability and desiccation resistance.Combined with transcriptomics,Cronobacter spp.could activate biofilm synthesis,produce more trehalose,accumulate betaine and electrolytes to stabilize intracellular structure under the two treatment conditions.A total of 31 and 43 genes were found related to desiccation and permeability resistance,respectively.And some genes(cysM,thuF,ycjO,etc.)were found to be associated with two tolerances for the first time.
基金Science Foundation for Distinguished Young Scholars 2020-JCJQ-ZQ-042 Intelligent and Bionic Spacecraft Thermal Control Technology Inspired by Tree Sap Transport Principle.
文摘As space technology advances,thermal control systems must effectively collect and dissipate heat from distributed,multi-source environments.Loop heat pipe is a highly reliable two-phase heat transfer component,but it has several limitations when addressing multi-source heat dissipation.Inspired by the transport and heat dissipation system of plants,large trees achieve stable and efficient liquid supply under the influence of two driving forces:capillary force during transpiration in the leaves(pull)and root pressure generated by osmotic pressure in the roots(push).The root pressure provides an effective liquid supply with a driving force exceeding 2 MPa,far greater than the driving force in conventional capillary-pumped two-phase loops.Research has shown that osmotic heat pipes offer a powerful driving force,and combining osmotic pressure with capillary force has significant advantages.Therefore,this paper designs a multi-evaporator,dual-drive two-phase loop,using both osmotic pressure and capillary force to solve the multi-source heat dissipation challenge.First,a transmembrane water flux model for the osmotic pressure-driven device was established to predict the maximum heat transfer capacity of the dual-drive two-phase loop.Then,an experimental setup for a multi-evaporator“osmotic pressure+capillary force”dual-drive two-phase loop was constructed,capable of transferring at least 235 W of power under a reverse gravity condition of 20 m.The study also analyzed the effects of reverse gravity height,heat load distribution among the three evaporators,startup sequence,and varying branch resistances on the performance of the dual-drive two-phase loop.
基金National Natural Science Foundation of China,Grant/Award Number:52175174China Postdoctoral Science Foundation,Grant/Award Number:2022M721791National Key Research and Development Program of China,Grant/Award Number:2020YFA0711003。
文摘Nanofluidic channels inspired by electric eels open a new era of efficient harvesting of clean blue osmotic energy from salinity gradients.Limited by less charge and weak ion selectivity of the raw material itself,energy conversion through nanofluidic channels is still facing considerable challenges.Here,a facile and efficient strategy to enhance osmotic energy harvesting based on drastically increasing surface charge density of MXenes subnanochannels via oxygen plasma is proposed.This plasma could break Ti–C bonds in the MXenes subnanochannels and effectively facilitate the formation of more Ti–O,C═O,O–OH,and rutile with a stronger negative charge and work function,which leads the surface potential of MXenes membrane to increase from 205 to 430 mV.This significant rise of surface charge endows the MXenes membrane with high cation selectivity,which could make the output power density of the MXenes membrane increase by 248.2%,reaching a high value of 5.92Wm^(−2) in the artificial sea‐river water system.Furthermore,with the assistance of low‐quality heat at 50℃,the osmotic power is enhanced to an ultrahigh value of 9.68Wm^(−2),which outperforms those of the state‐of‐the‐art two‐dimensional(2D)nanochannel membranes.This exciting breakthrough demonstrates the enormous potential of the facile plasma‐treated 2D membranes for osmotic energy harvesting.
基金supported by grants from the Natural Science Foundation of Hebei Province(Grant No.C2022204086)the Hebei Apple Innovation Team of Modern Agricultural Industry Technology System(Grant No.HBCT2021100211)the National Natural Science Foundation of China(Grant No.32072524).
文摘Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple(Malus×domestica Borkh.)remain unclear.Here,we functionally characterized the apple GroupⅢWRKY gene MdWRKY115.qRT-PCR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic stresses.GUS activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic stress.Subcellular localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal region.Transgenic analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic stresses.DNA affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene MdRD22.This binding was further verified by an electrophoretic mobility shift assay.Collectively,these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple.
基金supported by the National Natural Science Foundation of China(Grant Nos.32202542 and U20A2045)the Project of Major Science and Technology in Anhui Province(Grant No.202003a06020021)+2 种基金the Project of Science and Technology of Yunnan Province(Grant No.202102AE090038)Anhui Provincial Natural Science Foundation(Grant No.2108085QC121)the Natural Science Projects for Colleges and Universities in the Anhui Province(Grant No.KJ2021A0145)。
文摘Osmotic stress caused by low-temperature,drought and salinity was a prevalent abiotic stress in plant that severely inhibited plant development and agricultural yield,particularly in tea plant.Jasmonic acid(JA)is an important phytohormone involving in plant stress.However,underlying molecular mechanisms of JA modulated osmotic stress response remains unclear.In this study,high concentration of mannitol induced JA accumulation and increase of peroxidase activity in tea plant.Integrated transcriptome mined a JA signaling master,MYC2 transcription factor is shown as a hub regulator that induced by mannitol,expression of which positively correlated with JA biosynthetic genes(LOX and AOS)and peroxidase genes(PER).CsMYC2 was determined as a nuclei-localized transcription activator,furthermore,ProteinDNA interaction analysis indicated that CsMYC2 was positive regulator that activated the transcription of CsLOX7,CsAOS2,CsPER1 and CsPER3via bound with their promoters,respectively.Suppression of CsMYC2 expression resulted in a reduced JA content and peroxidase activity and osmotic stress tolerance of tea plant.Overexpression of CsMYC2 in Arabidopsis improved JA content,peroxidase activity and plants tolerance against mannitol stress.Together,we proposed a positive feedback loop mediated by CsMYC2,CsLOX7 and CsAOS2 which constituted to increase the tolerance of osmotic stress through fine-tuning the accumulation of JA levels and increase of POD activity in tea plant.
基金supported by grants from the National Natural Science Foundation of China(31971824,32170316)。
文摘SubclassⅢsucrose nonfermenting1-related protein kinase 2s(SnRK2s)function in ABA and abiotic stress responses by unknown mechanisms.We found that osmotic stress/ABA-activated protein kinase 10(SAPK10),a member of rice SnRK2s,physically interacted with CBL-interacting protein kinase 1(OsCIPK1).OsCIPK1 expression was up-regulated by ABA and PEG treatment,and overexpression increased the ABA sensitivity of seed germination and root growth and plant osmotic stress tolerance.Osmotic stress or ABA-induced activation of OsCIPK1 is dependent on SAPK10.SAPK10 phosphorylates Thr-24 of OsCIPK1 in vitro,and this phosphorylation increases the activity of OsCIPK1 and positively regulates the function of OsCIPK1 in ABA responses and plant osmotic stress tolerance.This study suggests that OsCIPK1 is a direct phosphorylated substrate of SAPK10,and SAPK10-mediated phosphorylation of OsCIPK1 functions in ABA signaling and increases rice osmotic stress tolerance.
基金China National Petroleum Corporation’s Fourteenth Five-Year Plan’s Prospective Fundamental Project on‘Research on Key Technologies and Equipment for Reservoir Reconstruction’(2021DJ45).
文摘Following large-scale volume fracturing in shale oil reservoirs,well shut-in measures are generally employed.Laboratory tests and field trials have underscored the efficacy of fracturing fluid imbibition during the shut-in phase in augmenting shale oil productivity.Unlike conventional reservoirs,shale oil reservoirs exhibit characteristics such as low porosity,low permeability,and rich content of organic matter and clay minerals.Notably,the osmotic pressure effects occurring between high-salinity formation water and low-salinity fracturing fluids are significant.The current understanding of the mobilization patterns of crude oil in micro-pores during the imbibition process remains nebulous,and the mechanisms underpinning osmotic pressure effects are not fully understood.This study introduces a theoretical approach,by which a salt ion migration control equation is derived and a mathematical model for spontaneous imbibition in shale is introduced,which is able to account for both capillary and osmotic pressures.Results indicate that during the spontaneous imbibition of low-salinity fluids,osmotic effects facilitate the migration of external fluids into shale pores,thereby complementing capillary forces in displacing shale oil.When considering both capillary and osmotic pressures,the calculated imbibition depth increases by 12%compared to the case where only capillary forces are present.The salinity difference between the reservoir and the fracturing fluids significantly influences the imbibition depth.Calculations for the shutin phase reveal that the pressure between the matrix and fractures reaches a dynamic equilibrium after 28 days of shut-in.During the production phase,the maximum seepage distance in the target block is approximately 6.02 m.
基金Science and Technology Department of Henan Pro vince Fund Project(Grant No.144300510019)
文摘Lappaconitine is a water-insoluble drug, which was used as model drug in this study. Currently, two osmotically controlled delivery systems that are widely used for water-insoluble drug are monolithic osmotic tablet （MOT） and push-pull osmotic pump （PPOP）. In the present study, lappaconitine solid dispersion monolithic osmotic tablet （lappaconitine-SD-MOT） and lappaconitine-PPOP were developed. The prepared lappaconitine-PPOP was able to delivery drug at the rate of approximate zero-order （r = 0.9931）, and the cumulative release was above 95.0%. The lappaconitine-SD-MOT showed a comparatively poor linearity when the data were plotted according to the zero-order equation （r = 0.9798）, and the cumulative release was 84.69%. Lappaconitine-PPOP exhibited better controlled drug release （higher regression value） compared with lappaconitine-SD-MOT. The similarity index （f2） between lappaconitine-PPOP and lappaconitine-SD-MOT was 49.1 （〈50）. A clear difference of drug release characteristics between the lappaconitine-SD-MOT and lappaconitine-PPOP was revealed. It indicated that the drug release performance of lappaconitine-PPOP could gain favorable zero-order kinetics and higher cumulative release compared with lappaconitine-SD-MOT. Therefore, these results suggested that PPOP was still a very effective device for the delivery of poorly water-soluble drug with zero-order pattern.
基金Supported by the Natural Science Foundation of Education Department of Jiangsu Province(02KJD18007)the Key Laboratory Program of Bio-re-sources of Jiangsu Province(KJS03042)the Key Program of Natural Science Foundation of Xuzhou Normal University(06XLA11)~~
文摘[ Objective] The purpose was to discuss drought resistance mechanism of Chenopodium album L. and supply theoretical basis and practical guidance for artificial cultivation and popularization of C. album. [ Method] C. album seedlings grown to 6th leaf stage were conducted osmotic stress treatment with PEG6000 osmotic whose concentration was set up as 0, 5%, 10% and 20% and the various physiological indices of the 3rd -5th function leaves in upper plant were determined after being treated for 0, 1,3, 5, 7 and 9 d. [ Result] Under osmotic stress with 5% PGE, the relative water content （RWC） of C. album reduced less. Under osmotic stress with 10%, the RWC in seedling leaves of C. album decreased to 62% on the fifth day and the leaves began to wither. Under osmotic stress with 20%, the RWC in seedling leaves of C. album decreased to 61.9% on the third day and the leaves appeared withering, and the RWC decreased to 48.6% on the 7th day and the leaves were dry and yellow. Proline contents in seedling leaves of C. album under osmotic stress with 5%, 10% and 20% PEG were 7.64, 10.9 and 29.4 times of CK on the 7th day. [ Conclusion] C. album hed some adaptability to moderate osmotic stress, but the PEG osmotic stress with high concentration and long time might lead to severe damage on C. album.
文摘Effects of sodium nitroprusside (SNP), a nitric oxide (NO) donor, on the germination and metabolism of reactive oxygen species were surveyed in wheat (Triticum aestivum L.) seeds. Germination of wheat seeds and even the elongation of radicle and plumule were dramatically promoted by SNP treatments during the germination under osmotic stress. Meanwhile, activities of amylase and EP were enhanced, thus leading to the degradation of storage reserve in seeds. After osmotic stress was removed, higher viability of wheat seeds was also maintained. In addition, the activities of CAT, APX and the content of proline were increased by SNP treatment simultaneously, but activities of LOX were inhibited, and both of which were beneficial for improving the antioxidant capacity during the germination of wheat seeds under osmotic stress. It was also shown that the increase of the activity of amylase induced by SNP in embryoless half-seeds of wheat in the beginning period of germination (6 h) might be indirectly related to GA(3).
基金Supported by National Natural Science Foundation of China(30771296 )Basic and Front Technology Research Program of Henan Province (082300430310)Foundation of Henan Educational Committee (2007180052)~~
文摘[Objective]The research aimed to probe into the mechanism of polyamine enhancing the tolerance of plants to drought stress and provide theoretical basis for application of polyamine in process of maize drought resistance. [Method]With PEG-6000 simulating natural drought,the change in content of soluble protein and relative water content were investigated in seedling leaves of two maize cultivars,Nongda 108 and Yedan 13 under osmotic stress with exogenous Spd treatment. [Result]On the 7th day,leaf relative water content and the content of soluble protein decreased more significantly in leaves of Yedan 13 （drought-sensitive） than in Nongda 108 （drought-tolerant）. Exogenous Spd treatment not only obviously inhibited the decrease of leaf relative water content,but also increased the content of soluble protein. [Conclusion]Exogenous Spd treatment could enhance the tolerance of maize seedlings to osmotic stress,via improving the content of soluble protein in seedling leaves.
基金National Science & Technology Pillar Program during the 12~(th) Five-year Plan Period(Grant No.2012BAI29B08)
文摘The objective of this study was to prepare monolithic osmotic tablet of quercetin for controlled drug release. Quercetin-PVP solid dispersion was prepared to enhance its solubility and dissolution rate. Solid dispersion, suspending agents, osmotic agents and other conventional excipients were used as tablet core composition and cellulose acetate （CA） with plasticizer as release controlling membrane. Different formulation variables, the amounts of PEO （polyethylene oxide）, NaC1, plasticizer, and coating weight gain were optimized to gain the optimum formulation. The mechanism of drug release from monolithic osmotic tablet was also discussed. The optimal monolithic osmotic pump tablet could deliver quercetin at the rate of approximate zero-order up to 12 h, and the cumulative release was 90.74%. The developed monolithic osmotic system for quercetin loaded by solid dispersion was found to be a promising approach for controlled release of poorly-water soluble drug candidates.
基金Supported by National Scientific and Technological Project in Rural Areas in the "Twelfth Five Year" Plan(2012BAD21B03,2012BAD21B0304)~~
文摘[Objective] This study aimed to investigate the effects of drought stress on osmotic regulation substances of Catalpa bungei clones. [Method] Potting experimental was carried out with plastic film sealing method, to differentiate the degrees of drought stress based on changes in soil water content and leaf water potential and investigate variations in contents of osmotic regulation substances（free proline,soluble sugar and soluble protein） in leaves of five Catalpa bungei clones under different degrees of drought stresses. [Result] According to changes in soil water content and leaf water potential, the whole process of drought stress was divided into normal level（CK, with soil water content of 97.49% and leaf water potential of-0.54MPa）, light drought（LD with soil water content of 59.96% and leaf water potential of-1.28 MPa）, mediate drought（MD with soil water content of 34.19% and leaf water potential of-2.32 MPa） and severe drought（SD with soil water content of 14.52%and leaf water potential of-2.99 MPa）. The soil water content and leaf water potential of five Catalpa bungei clones reached the highest correlation in exponential fitting, with an average R2of 0.989 3（P0.001）. The free proline content in leaves of five Catalpa bungei clones increased rapidly with the increasing degree of drought stress（P 0.001）. To be specific, free proline contents of Catalpa bungei clones015-1 and 7080 were 34.39 and 33.41 times of the normal level under severe drought conditions, which reached an extremely significant level（P0.001）; the free proline content of Catalpa bungei clone 1-3 rapidly increased to（855.46±227.52） μg/g Fw under light drought conditions. The soluble protein content in leaves showed different variation trends. To be specific, the soluble protein content of Catalpa bungei clone 7080 was the lowest at various drought stages and reached（1.644 ±0.137）mg/g Fw under normal conditions; the soluble protein content of Catalpa bungei clone 1-3 was relatively high under normal conditions and was reduced rapidly under light drought conditions, showing different response patterns. [Conclusion] Osmotic regulation substances in leaves of five Catalpa bungei clones all have certain response to drought stress. Free proline is the most important osmotic regulation substance, followed by soluble protein, while soluble sugar makes no significant contribution. According to changes in content of osmotic regulation substances, Catalpa bungei clone 7080 has relatively high capacity and good drought resistance, while Catalpa bungei clone 1-3 has the rapidest response to drought stress.
文摘Four rice ( Oryza sativa L.) cultivars 'IR72', 'Tesanai 2', 'Guichao 2' and 'IIyou 4480' were grown in two plastic house (15 m×3 m) with 35 μmol/mol and 60 μmol/mol CO 2 concentration which was controlled by computer. As compared with rice at ambient 35 μmol/mol CO 2, the changes in photosynthetic rate at elevated CO 2 showed up_regulation ('IR72' and 'Tesanai 2'), stable (unchanged) in 'Guichao 2' and down_regulation type ('IIyou 4480'). Growth rate, panicle weight, integrated water use efficiency (WUE) calculated from Δ 13 C and the capacity of scavenging DPPH · (1,1_diphenyl_2_picrylhydrazyl) free radical were increased at elevated CO 2. An increment in total biomass was observed in three cultivars by elevated CO 2, with the exception of 'IIyou 4480'. Ratios of panicle weight/total biomass were altered to different extents in tested cultivars by elevated CO 2. When leaf segments were subjected to PEG osmotic stress, the electrolyte leakage rate from leaves grown at elevated CO 2 was less than that at 35 μmol/mol CO 2. Those intraspecific variations of rice imply a possibility for selecting cultivars with maximal productivity and high tolerance to stresses adapted to elevated CO 2 in the future.
文摘In previous studies, compound mefformin/glipizide was developed. Aim To discover the mechanism of drug release from factors influencing drug release from dosage form （the semi-permeable cry orifice） were investigated. Results The influx of water that elementary osmotic pump tablet it. Methods Three rate-limiting membrane, tablet core and delivpassed the osmotic pump tablet was almost equal to the metformin release rate, while it was greatly less than the drug dissolution rate from tablet core. The size of orifice from 0. 4 mm to 0.8 mm had no influence on drug release. The osmotic pressure of tablet core was mainly caused by mefformin. Conclusion From the developed model of osmotic pump systems, it can be seen that only the water influx through the membrane is a rate-limiting step, not tablet core dissolution rate and solution influx, and only when the core dissolution rate is equal to the solution influx, the zero order release is seen in the osmotic pump systems.
基金Supported by the grants from the National Natural Science Foundation of China.
文摘With light and electron microscopy the substructural change and the ATPase activity of corn (Zea mays L.) root cap cells after short-term osmotic stress were studied. Some spoke-like fine strands originating from the departed periplasm and stretching towards cell wall could be observed even after plasmolysis. By observing the precipitation of ATPase activity product (lead phosphate) at plasma membrane and plasmodesmata, it was found that the fine strands were plasma membrane-lined channels surrounding the cytoplasm and that they still firmly connected to the plasmodesmata during plasmolysis. Compared with the control (unstressed), a sharp decrease of ATPase activity in the plasmodesmata of the stressed cells was observed. Inhibition of energy metabolism in these limited locales would affect the physiological activity, maybe including the regulation of permeability and the change of size exclusion limit (SEL) of plasmodesmata.
文摘The clinical pharmacokinetics of osmotic pump controlled release tablets of terazosin hydrochloride in healthy volunteers was studied.A sensitive and rapid HPLC method was used to determine the terazosin plasma concentrations,and single and multiple doses of terazosin hydrochloride regular tablets（reference tablets）and osmotic pump controlled release tablets were orally administrated in randomized crossover design.The results showed that the C_（max）of the reference tablets after single oral dose（（120.56±23.15）ng/mL）in 20 healthy volunteers was significantly higher than that of controlled release tablets （（95.27±16.35）ng/mL）.The T_（max）of the controlled release tablets（（2.65±0.82）h）was significantly longer than that of reference tablets（（1.27±0.61）h）（P0.05）.The relative bioavailability of the controlled release tablets was found to be（105.85±6.12）%. The multiple oral dose pharmacokinetic parameters of the regular tablets and controlled release tablets were as follows：AUC_（SS） were（1275.17±175.35）and（1382.65±205.31）ng·h/mL respectively,C_（max）were（128.15±22.37）and（98.57±18.16）ng/mL respectively,T_（max）were（1.35±0.71）and（2.76±0.85）h respectively,C_（av）were（53.13±9.12）and（57.61±9.25）ng/mL respectively, and DF were（2.25±0.26）%and（1.62±0.25）%respectively.The relative bioavailability of the controlled release tablets to the reference tablets was（108.43±6.26）%.The controlled release tablet of terazosin hydrochloride was bioequivalent to the reference tablet.The controlled release tablet exhibited a sustained-release property with a significantly longer T_（max）and lower C_（max）.
