Let R_1 and R_2 be two rings with unit I. We give some characterizations of ring homomorphisms and ring isomorphisms between R_1 and R_2 in term of complete preservers of fixed points of multipliers, under some mild a...Let R_1 and R_2 be two rings with unit I. We give some characterizations of ring homomorphisms and ring isomorphisms between R_1 and R_2 in term of complete preservers of fixed points of multipliers, under some mild assumption on R_1. Applications to several kinds of operator algebras such as Banach algebras, nest algebras, matrix algebras and standard operator algebras are presented.展开更多
Suppose R is an idempotence-diagonalizable ring. Let n and m be two arbitrary positive integers with n ≥ 3. We denote by Mn(R) the ring of all n x n matrices over R. Let (Jn(R)) be the additive subgroup of Mn(...Suppose R is an idempotence-diagonalizable ring. Let n and m be two arbitrary positive integers with n ≥ 3. We denote by Mn(R) the ring of all n x n matrices over R. Let (Jn(R)) be the additive subgroup of Mn(R) generated additively by all idempotent matrices. Let JJ = (Jn(R)) or Mn(R). We describe the additive preservers of idempotence from JJ to Mm(R) when 2 is a unit of R. Thereby, we also characterize the Jordan (respectively, ring and ring anti-) homomorphisms from Mn (R) to Mm (R) when 2 is a unit of R.展开更多
Let B(X) be the algebra of all bounded linear operators on an infinite-dimensional complex or real Banach space X. Given an integer n 〉 1, we show that an additive surjective map Ф on B(X) preserves Drazin inver...Let B(X) be the algebra of all bounded linear operators on an infinite-dimensional complex or real Banach space X. Given an integer n 〉 1, we show that an additive surjective map Ф on B(X) preserves Drazin invertible operators of index non-greater than n in both directions if and only if Ф is either of the form Ф(T) = aATA-1 or of the form Ф(T) = aBT*B-1 where a is a non-zero scalar, A : X → X and B : X* → X are two bounded invertible linear or conjugate linear operators.展开更多
Let H be a complex Hilbert space of dimension greater than 2, and B(H) denote the Banach algebra of all bounded linear operators on H. For A, B C B(H), define the binary relation A ≤ B by A*A = A*B and AA* = A...Let H be a complex Hilbert space of dimension greater than 2, and B(H) denote the Banach algebra of all bounded linear operators on H. For A, B C B(H), define the binary relation A ≤ B by A*A = A*B and AA* = AB*. Then (B(H), "〈.") is a partially ordered set and the relation "≤" is called the star order on B(H). Denote by Bs(H) the set of all self-adjoint operators in B(H). In this paper, we first characterize nonlinear continuous bijective maps on Bs(H) which preserve the star order in both directions. We characterize also additive maps (or linear maps) on B(H) (or nest algebras) which are multiplicative at some invertible operator.展开更多
The spatiotemporal characterization of plume sedimentation and microorganisms is critical for developing plume ecological monitoring model.To address the limitations of traditional methods in obtaining high-quality se...The spatiotemporal characterization of plume sedimentation and microorganisms is critical for developing plume ecological monitoring model.To address the limitations of traditional methods in obtaining high-quality sediment,a novel sampling system with 6000 m operational capability and three-month endurance was developed.It is equipped with three sediment samplers,a set of formaldehyde preservation solution injection devices.The system is controlled by a low-power,timing-triggered controllers.To investigate low-disturbance rheological mechanisms,gap controlled rheological tests were conducted to optimize the structural design of the sampling and sealing assembly.Stress-controlled shear rheological tests were employed to investigate the mechanisms governing yield stress in sediments under varying temperature conditions and boundary roughness.Additionally,the coupled Eulerian-Lagrangian(CEL)method and sediment rheological constitutive models were employed to simulate tube-soil interaction dynamics and sediment disturbance.The radial heterogeneity of sediment disturbance and friction variation of the sampling tube were revealed.The tube was completely“plugged”at a penetration depth of 261 mm,providing critical data support to the penetration depth parameters.The deep-sea pressure test and South China Sea field trials demonstrated the system’s capability to collect and preserve quantitative time-series sediment samples with high fidelity.展开更多
Instrument separation is a critical complication during root canal therapy,impacting treatment success and long-term tooth preservation.The etiology of instrument separation is multifactorial,involving the intricate a...Instrument separation is a critical complication during root canal therapy,impacting treatment success and long-term tooth preservation.The etiology of instrument separation is multifactorial,involving the intricate anatomy of the root canal system,instrument-related factors,and instrumentation techniques.Instrument separation can hinder thorough cleaning,shaping,and obturation of the root canal,posing challenges to successful treatment outcomes.Although retrieval of separated instrument is often feasible,it carries risks including perforation,excessive removal of tooth structure and root fractures.Effective management of separated instruments requires a comprehensive understanding of the contributing factors,meticulous preoperative assessment,and precise evaluation of the retrieval difficulty.The application of appropriate retrieval techniques is essential to minimize complications and optimize clinical outcomes.The current manuscript provides a framework for understanding the causes,risk factors,and clinical management principles of instrument separation.By integrating effective strategies,endodontists can enhance decision-making,improve endodontic treatment success and ensure the preservation of natural dentition.展开更多
To address the challenges in studying the pore formation and evolution processes,and unclear preservation mechanisms of deep to ultra-deep carbonate rocks,a high-temperature and high-pressure visualization simulation ...To address the challenges in studying the pore formation and evolution processes,and unclear preservation mechanisms of deep to ultra-deep carbonate rocks,a high-temperature and high-pressure visualization simulation experimental device was developed for ultra-deep carbonate reservoirs.Carbonate rock samples from the Sichuan Basin and Tarim Basin were used to simulate the dissolution-precipitation process of deep to ultra-deep carbonate reservoirs in an analogous geological setting.This unit comprises four core modules:an ultra-high temperature,high pressure triaxial stress core holder module(temperature higher than 300°C,pressure higher than 150 MPa),a multi-stage continuous flow module with temperature-pressure regulation,an ultra-high temperature-pressure sapphire window cell and an in-situ high-temperature-pressure fluid property measurement module and real-time ultra-high temperature-pressure permeability detection module.The new experimental device was used for simulation experiment,the geological insights were obtained in three aspects.First,the pore-throat structure of carbonate is controlled by lithology and initial pore-throat structure,and fluid type,concentration and dissolution duration determine the degree of dissolution.The dissolution process exhibits two evolution patterns.The dissolution scale is positively correlated to the temperature and pressure,and the pore-forming peak period aligns well with the hydrocarbon generation peak period.Second,the dissolution potential of dolomite in an open flow system is greater than that of limestone,and secondary dissolved pores formed continuously are controlled by the type and concentration of acidic fluids and the initial physical properties.These pores predominantly distribute along pre-existing pore/fracture zones.Third,in a nearly closed diagenetic system,after the chemical reaction between acidic fluids and carbonate rock reaches saturation and dynamic equilibrium,the pore structure no longer changes,keeping pre-existing pores well-preserved.These findings have important guiding significance for the evaluation of pore-throat structure and development potential of deep to ultra-deep carbonate reservoirs,and the prediction of main controlling factors and distribution of high-quality carbonate reservoirs.展开更多
The umbrella term"neurodege ne rative disorders"(NDDs) refers to several conditions characterized by a progressive loss of structure and function of cells belonging to the nervous system.Such diseases affect...The umbrella term"neurodege ne rative disorders"(NDDs) refers to several conditions characterized by a progressive loss of structure and function of cells belonging to the nervous system.Such diseases affect more than 50million people worldwide.Neurodegenerative disorders are characterized by sundry factors and pathophysiological mechanisms that a re challenging to be fully profiled.Many of these rely on cell signaling pathways to preserve homeostasis,involving second messengers such as cyclic adenosine monophosphate (cAMP)and cyclic guanosine 3',5'-monophosphate(cGMP).Their ability to control the duration and amplitude of the signaling cascade is given by the presence of several common and uncommon effectors.Protein kinases A and G (PKA and PKG),phosphodiesterases (PDEs),and scaffold proteins are among them.展开更多
In addition to the organic matter type,abundance,thermal maturity,and shale reservoir space,the preservation conditions of source rocks play a key factor in affecting the quantity and quality of retained hydrocarbons ...In addition to the organic matter type,abundance,thermal maturity,and shale reservoir space,the preservation conditions of source rocks play a key factor in affecting the quantity and quality of retained hydrocarbons in source rocks of lacustrine shale,yet this aspect has received little attention.This paper,based on the case analysis,explores how preservation conditions influence the enrichment of mobile hydrocarbons in shale oil.Research showns that good preservation conditions play three key roles.(1)Ensure the retention of sufficient light hydrocarbons(C_(1)–C_(13)),medium hydrocarbons(C_(14)–C_(25))and small molecular aromatics(including 1–2 benzene rings)in the formation,which enhances the fluidity and flow of shale oil;(2)Maintain a high energy field(abnormally high pressure),thus facilitating the maximum outflow of shale oil;(3)Ensure that the retained hydrocarbons have the miscible flow condition of multi-component hydrocarbons(light hydrocarbons,medium hydrocarbons,heavy hydrocarbons,and heteroatomic compounds),so that the heavy hydrocarbons(C_(25+))and heavy components(non-hydrocarbons and asphaltenes)have improved fluidity and maximum flow capacity.In conclusion,in addition to the advantages of organic matter type,abundance,thermal maturity,and reservoir space,good preservation conditions of shale layers are essential for the formation of economically viable shale oil reservoirs,which should be incorporated into the evaluation criteria of shale oil-rich areas/segments and considered a necessary factor when selecting favorable exploration targets.展开更多
To alleviate the quality deterioration and extend the shelf life of crucian carp fillets,a bio-based active composite film integrating eugenol(EG)-loaded mesoporous silica nanoparticles(MSNs)modified with caffeic acid...To alleviate the quality deterioration and extend the shelf life of crucian carp fillets,a bio-based active composite film integrating eugenol(EG)-loaded mesoporous silica nanoparticles(MSNs)modified with caffeic acid(CA)within the zein matrix(EG/CA-MSN/Zein)was developed.This study compared the effects of EG/CA-MSN/Zein,polyethylene(PE),and zein films on the quality of fish fillets during refrigerated storage.The results showed that the EG/CA-MSN/Zein film significantly retarded the increase in pH and microbial growth.Moreover,the film had higher water-holding capacity(WHC),better texture,and color stability,as indicated by low-field nuclear magnetic resonance(LF-NMR),magnetic resonance imaging(MRI),and sensory evaluation.The EG/CA-MSN/Zein composite film extended the shelf life of crucian carp fillets by 3-4 days,highlighting its potential as an environmentally friendly and efficient packaging material for aquatic products.展开更多
In this study,composite films consisting of polylactic acid(PLA),ethyl cellulose(EC),and zein were prepared by solution casting method,and their performance and application in chilled fresh meat preservation were inve...In this study,composite films consisting of polylactic acid(PLA),ethyl cellulose(EC),and zein were prepared by solution casting method,and their performance and application in chilled fresh meat preservation were investigated.The results showed that the three materials had satisfactory compatibility in the composite film.Addition of EC and zein effectively improved the mechanical properties,thermodynamic properties,surface hydrophilicity,oxygen permeability,and degradation properties of PLA films.When the ratio of PLA to EC was 3:7,the tensile strength and elongation at break reached maximum values of 16.6 MPa and 30.5%,respectively.Moreover,under different conditions,the composite film exhibited better degradability than the PLA film.The composite film with a 3:7 ratio of PLA to EC had the best performance,with a degradation rate of 21.75%after 84 days.Chilled fresh meat wrapped with the composite film showed significantly improved antioxidant,antibacterial,and water-holding properties.展开更多
Chinese President Xi Jinping calls for honoring history to preserve peace,as the country commemorates the 80th anniversary of its hard-won victory in WWII.
In Maizhokunggar County of Lhasa City,the Xizang Autonomous Region,a precious intangible cultural heritage is preserved-the traditional craft of Zaxoi drum making,which carries profound historical and cultural signifi...In Maizhokunggar County of Lhasa City,the Xizang Autonomous Region,a precious intangible cultural heritage is preserved-the traditional craft of Zaxoi drum making,which carries profound historical and cultural significance.After hundreds of years,its unique value continues to shine through the passage of time.For more than 40 years,Kongcho Dondrup,an inheritor of this craftsmanship,has poured his heart into preserving and promoting this ancient art.展开更多
Recent advances in organ transplantation,regenerative medicine,and drug discovery have emphasized the critical importance of effective preservation techniques for organs.Despite these advances,current preservation tec...Recent advances in organ transplantation,regenerative medicine,and drug discovery have emphasized the critical importance of effective preservation techniques for organs.Despite these advances,current preservation techniques have significant limitations in maintaining the viability and functional efficacy of organs over the long term.As a result,there is a pressing need to develop reliable and efficient preservation strategies for organs.Currently,the clinical standard for organ preservation involves the use of static cold storage and organ machine perfusion,but these methods can only preserve organs for a couple of days or even a few hours.Notably,the development of cryobiology has yielded promising alternatives.In this review,we aim to provide a comprehensive overview of the progression of organ preservation methods,while emphasizing the limitations of traditional approaches.Moreover,we evaluate advanced preservation techniques for organs,including kidneys,livers,hearts,lungs,and intestines.Furthermore,we share a progress perspective on the future of organ preservation,with the ultimate goal of achieving viable long-term preservation to address the pressing issue of organ shortage.展开更多
A precious heritage from ancient times,the Beijing-Hangzhou Grand Canal has renewed its former glory through ecological rehabilitation and cultural preservation over the past decades.
There is growing concern about the concept that exposure to environmental chemicals may be contributing to the obesity epidemic.However,there is no consensus on the obesogenic effects of emerging contaminants from a t...There is growing concern about the concept that exposure to environmental chemicals may be contributing to the obesity epidemic.However,there is no consensus on the obesogenic effects of emerging contaminants from a toxicological and environmental perspective.The potential human exposure and experimental evidence for obesogenic effects of emerging contaminants need to be systematically discussed.The main objective of this review is to provide recommendations for further subsequent policy development following a critical analysis of the literature for humans and experimental animals exposed to emerging contaminants.This article reviews human exposure to emerging contaminants(with a focus on antimicrobials,preservatives,water and oil repellents,flame retardants,antibiotics and bisphenols)and the impact of emerging contaminants on obesity.These emerging contaminants have been widely detected in human biological samples.Epidemiological studies provide evidence linking exposure to emerging contaminants to the risks of obesity in humans.Studies based on animalmodels and adipose cells show the obesogenic effects of emerging contaminants and identify modes of action by which contaminants may induce changes in body fat accumulation and lipid metabolic homeostasis.Some knowledge gaps in this area and future directions for further investigation are discussed.展开更多
Decays resulting from infections by Geotrichum citri-aurantii cause a significant reduction in citrus postharvest quality and marketable yield.In the present work,0.8 mol·L^(-1)NaCl of Generally Recognized as Saf...Decays resulting from infections by Geotrichum citri-aurantii cause a significant reduction in citrus postharvest quality and marketable yield.In the present work,0.8 mol·L^(-1)NaCl of Generally Recognized as Safe(GRAS)salts were identified to have complete inhibition activity to G.citriaurantii in vitro and in vivo.An inhibitory mechanism study showed that 0.1 mol·L^(-1)NaCl changed the expression of six genes(Gci002087,Gci003354,Gci000013,Gci000394,Gci003505 and Gci004433)in target of rapamycin(TOR)pathway,thus inducing a large number of lipid droplets(LDs)accumulation with TEM observations and staining.In vivo,0.1 mol·L^(-1)NaCl could raise up the activities of CAT,PAL,PPO and cellulase which hence to strengthen the ability of resistance tolerance of citrus.In addition,NaCl not only accelerated the growth of the biocontrol yeast Kloeckera apiculata strain 34-9,but also increased the expression level of adhesin-encoding genes and biofilm-formation encoding gene(34-9-3691).Finally,the storage experiments in 3 months demonstrated that the combination of NaCl and the yeast 34-9 could keep fresh,reduce decay and prolong its shelf-life,thus implying that the combination of biocontrol strain and GRAS salts has been explored as a promising alternative to synthetic fungicides.展开更多
Premature ovarian insufficiency(POI)caused by chemotherapy is a common complication in female cancer survivors of childbearing age.Traditional methods,including mesenchymal stem cell(MSC)transplant and hormone replace...Premature ovarian insufficiency(POI)caused by chemotherapy is a common complication in female cancer survivors of childbearing age.Traditional methods,including mesenchymal stem cell(MSC)transplant and hormone replacement therapy,have limited clinical application because of their drawbacks,and more methods need to be developed.In the current study,the potential effects and underlying mechanisms of human umbilical cord MSC-derived extracellular vesicles(h UCMSC-EVs)were investigated in a cisplatin(CDDP)-induced POI mouse model and a human granulosa cell(GC)line.The results showed that h UCMSC-EVs significantly attenuated body weight loss,ovarian weight loss,ovary atrophy,and follicle loss in moderate-dose(1.5 mg/kg)CDDP-induced POI mice,similar to the effects observed with h UCMSCs.We further found that the h UCMSCEVs inhibited CDDP-induced ovarian GC apoptosis by upregulating anti-apoptotic mi RNA levels in GCs,thereby downregulating the m RNA levels of multiple pro-apoptotic genes.In general,our findings indicate that the moderate-dose chemotherapy may be a better choice for clinical oncotherapy,considering effective rescue of the oncotherapy-induced ovarian damage with h UCMSC-EVs.Additionally,multiple mi RNAs in h UCMSC-EVs may potentially be used to inhibit the chemotherapy-induced ovarian GC apoptosis,thereby restoring ovarian function and improving the life quality of female cancer patients.展开更多
Mold spoilage and nutrition enrichment are major concerns of Chinese steamed bread,and using functional lactic acid bacteria as starter to play the role of in-situ preservation and nutritional fortification was a prom...Mold spoilage and nutrition enrichment are major concerns of Chinese steamed bread,and using functional lactic acid bacteria as starter to play the role of in-situ preservation and nutritional fortification was a promising alternative.Hence,Lactiplantibacillus plantarum P10 capable of inhibiting spoilage microorganisms and producing γ-aminobutyric acid(GABA)(380 mg/L)was screened from Chinese pickle.Metabolomics analysis showed that P10 produced key antimicrobial metabolites mainly including ten organic acids,aldehyde,alkaloid.Besides,P10 might exhibit health beneficial effects such as degrading cholesterol,lowering blood glucose and reducing uric acid due to the production of deoxycholic acid and Ile-Pro-Ile,and the degradation of purine.Finally,the promising application potential of P10 was evidenced in steamed bread with extended shelf life,excellent anti-aging effect,and 24.5-fold enrichment of GABA.Conclusively,this investigation could provide scientific basis for the application of P10 as a functional starter in steamed bread.展开更多
悦读·明其义.A legacy of wilderness.荒野的遗产.In an era where urbanization and industrialization are rapidly expanding,nurturing nature has become not just a passion but a professional qualification for many envi...悦读·明其义.A legacy of wilderness.荒野的遗产.In an era where urbanization and industrialization are rapidly expanding,nurturing nature has become not just a passion but a professional qualification for many environmentalists and conservationists.Our planet is home to some of the most splendid natural scenery,yet human activities continue to disturb these delicate ecosystems.The responsibility to protect and preserve these wonders lies with each of us,as the consequences of neglect grow increasingly severe.展开更多
基金Supported by the National Natural Science Foundation of China(Grant No.11671294)
文摘Let R_1 and R_2 be two rings with unit I. We give some characterizations of ring homomorphisms and ring isomorphisms between R_1 and R_2 in term of complete preservers of fixed points of multipliers, under some mild assumption on R_1. Applications to several kinds of operator algebras such as Banach algebras, nest algebras, matrix algebras and standard operator algebras are presented.
基金This work is supported in part by the Chinese Natural Science Foundation under Grant No. 10671026 and the Postdoctoral Fund of Heilongjiang Province
文摘Suppose R is an idempotence-diagonalizable ring. Let n and m be two arbitrary positive integers with n ≥ 3. We denote by Mn(R) the ring of all n x n matrices over R. Let (Jn(R)) be the additive subgroup of Mn(R) generated additively by all idempotent matrices. Let JJ = (Jn(R)) or Mn(R). We describe the additive preservers of idempotence from JJ to Mm(R) when 2 is a unit of R. Thereby, we also characterize the Jordan (respectively, ring and ring anti-) homomorphisms from Mn (R) to Mm (R) when 2 is a unit of R.
文摘Let B(X) be the algebra of all bounded linear operators on an infinite-dimensional complex or real Banach space X. Given an integer n 〉 1, we show that an additive surjective map Ф on B(X) preserves Drazin invertible operators of index non-greater than n in both directions if and only if Ф is either of the form Ф(T) = aATA-1 or of the form Ф(T) = aBT*B-1 where a is a non-zero scalar, A : X → X and B : X* → X are two bounded invertible linear or conjugate linear operators.
基金Supported by National Natural Science Foundation of China (Grant Nos. 10871111, 10501029) and the Specialized Research Fund for Doctoral Program of Higher Education (Grant No. 200800030059)
文摘Let H be a complex Hilbert space of dimension greater than 2, and B(H) denote the Banach algebra of all bounded linear operators on H. For A, B C B(H), define the binary relation A ≤ B by A*A = A*B and AA* = AB*. Then (B(H), "〈.") is a partially ordered set and the relation "≤" is called the star order on B(H). Denote by Bs(H) the set of all self-adjoint operators in B(H). In this paper, we first characterize nonlinear continuous bijective maps on Bs(H) which preserve the star order in both directions. We characterize also additive maps (or linear maps) on B(H) (or nest algebras) which are multiplicative at some invertible operator.
基金supported by the National Key R&D Program of China(No.2022YFC2803900)the National Natural Science Foundation of China(No.42276191)Zhejiang University Students Science and Technology Innovation Activity Plan(New Talent Plan)(No.2024R401185).
文摘The spatiotemporal characterization of plume sedimentation and microorganisms is critical for developing plume ecological monitoring model.To address the limitations of traditional methods in obtaining high-quality sediment,a novel sampling system with 6000 m operational capability and three-month endurance was developed.It is equipped with three sediment samplers,a set of formaldehyde preservation solution injection devices.The system is controlled by a low-power,timing-triggered controllers.To investigate low-disturbance rheological mechanisms,gap controlled rheological tests were conducted to optimize the structural design of the sampling and sealing assembly.Stress-controlled shear rheological tests were employed to investigate the mechanisms governing yield stress in sediments under varying temperature conditions and boundary roughness.Additionally,the coupled Eulerian-Lagrangian(CEL)method and sediment rheological constitutive models were employed to simulate tube-soil interaction dynamics and sediment disturbance.The radial heterogeneity of sediment disturbance and friction variation of the sampling tube were revealed.The tube was completely“plugged”at a penetration depth of 261 mm,providing critical data support to the penetration depth parameters.The deep-sea pressure test and South China Sea field trials demonstrated the system’s capability to collect and preserve quantitative time-series sediment samples with high fidelity.
文摘Instrument separation is a critical complication during root canal therapy,impacting treatment success and long-term tooth preservation.The etiology of instrument separation is multifactorial,involving the intricate anatomy of the root canal system,instrument-related factors,and instrumentation techniques.Instrument separation can hinder thorough cleaning,shaping,and obturation of the root canal,posing challenges to successful treatment outcomes.Although retrieval of separated instrument is often feasible,it carries risks including perforation,excessive removal of tooth structure and root fractures.Effective management of separated instruments requires a comprehensive understanding of the contributing factors,meticulous preoperative assessment,and precise evaluation of the retrieval difficulty.The application of appropriate retrieval techniques is essential to minimize complications and optimize clinical outcomes.The current manuscript provides a framework for understanding the causes,risk factors,and clinical management principles of instrument separation.By integrating effective strategies,endodontists can enhance decision-making,improve endodontic treatment success and ensure the preservation of natural dentition.
基金Supported by the Joint Fund for Enterprise Innovation and Development of the National Natural Science Foundation of China(U23B20154)General Program of the National Natural Science Foundation of China(42372169)。
文摘To address the challenges in studying the pore formation and evolution processes,and unclear preservation mechanisms of deep to ultra-deep carbonate rocks,a high-temperature and high-pressure visualization simulation experimental device was developed for ultra-deep carbonate reservoirs.Carbonate rock samples from the Sichuan Basin and Tarim Basin were used to simulate the dissolution-precipitation process of deep to ultra-deep carbonate reservoirs in an analogous geological setting.This unit comprises four core modules:an ultra-high temperature,high pressure triaxial stress core holder module(temperature higher than 300°C,pressure higher than 150 MPa),a multi-stage continuous flow module with temperature-pressure regulation,an ultra-high temperature-pressure sapphire window cell and an in-situ high-temperature-pressure fluid property measurement module and real-time ultra-high temperature-pressure permeability detection module.The new experimental device was used for simulation experiment,the geological insights were obtained in three aspects.First,the pore-throat structure of carbonate is controlled by lithology and initial pore-throat structure,and fluid type,concentration and dissolution duration determine the degree of dissolution.The dissolution process exhibits two evolution patterns.The dissolution scale is positively correlated to the temperature and pressure,and the pore-forming peak period aligns well with the hydrocarbon generation peak period.Second,the dissolution potential of dolomite in an open flow system is greater than that of limestone,and secondary dissolved pores formed continuously are controlled by the type and concentration of acidic fluids and the initial physical properties.These pores predominantly distribute along pre-existing pore/fracture zones.Third,in a nearly closed diagenetic system,after the chemical reaction between acidic fluids and carbonate rock reaches saturation and dynamic equilibrium,the pore structure no longer changes,keeping pre-existing pores well-preserved.These findings have important guiding significance for the evaluation of pore-throat structure and development potential of deep to ultra-deep carbonate reservoirs,and the prediction of main controlling factors and distribution of high-quality carbonate reservoirs.
文摘The umbrella term"neurodege ne rative disorders"(NDDs) refers to several conditions characterized by a progressive loss of structure and function of cells belonging to the nervous system.Such diseases affect more than 50million people worldwide.Neurodegenerative disorders are characterized by sundry factors and pathophysiological mechanisms that a re challenging to be fully profiled.Many of these rely on cell signaling pathways to preserve homeostasis,involving second messengers such as cyclic adenosine monophosphate (cAMP)and cyclic guanosine 3',5'-monophosphate(cGMP).Their ability to control the duration and amplitude of the signaling cascade is given by the presence of several common and uncommon effectors.Protein kinases A and G (PKA and PKG),phosphodiesterases (PDEs),and scaffold proteins are among them.
基金Supported by the National Natural Science Foundation of China(U22B6004)Project of PetroChina Research Institute of Petroleum Exploration and Development(2022yjcq03)Core Technology Key Project of China Petroleum Changqing Oilfield Company(KJZX2023-01).
文摘In addition to the organic matter type,abundance,thermal maturity,and shale reservoir space,the preservation conditions of source rocks play a key factor in affecting the quantity and quality of retained hydrocarbons in source rocks of lacustrine shale,yet this aspect has received little attention.This paper,based on the case analysis,explores how preservation conditions influence the enrichment of mobile hydrocarbons in shale oil.Research showns that good preservation conditions play three key roles.(1)Ensure the retention of sufficient light hydrocarbons(C_(1)–C_(13)),medium hydrocarbons(C_(14)–C_(25))and small molecular aromatics(including 1–2 benzene rings)in the formation,which enhances the fluidity and flow of shale oil;(2)Maintain a high energy field(abnormally high pressure),thus facilitating the maximum outflow of shale oil;(3)Ensure that the retained hydrocarbons have the miscible flow condition of multi-component hydrocarbons(light hydrocarbons,medium hydrocarbons,heavy hydrocarbons,and heteroatomic compounds),so that the heavy hydrocarbons(C_(25+))and heavy components(non-hydrocarbons and asphaltenes)have improved fluidity and maximum flow capacity.In conclusion,in addition to the advantages of organic matter type,abundance,thermal maturity,and reservoir space,good preservation conditions of shale layers are essential for the formation of economically viable shale oil reservoirs,which should be incorporated into the evaluation criteria of shale oil-rich areas/segments and considered a necessary factor when selecting favorable exploration targets.
文摘To alleviate the quality deterioration and extend the shelf life of crucian carp fillets,a bio-based active composite film integrating eugenol(EG)-loaded mesoporous silica nanoparticles(MSNs)modified with caffeic acid(CA)within the zein matrix(EG/CA-MSN/Zein)was developed.This study compared the effects of EG/CA-MSN/Zein,polyethylene(PE),and zein films on the quality of fish fillets during refrigerated storage.The results showed that the EG/CA-MSN/Zein film significantly retarded the increase in pH and microbial growth.Moreover,the film had higher water-holding capacity(WHC),better texture,and color stability,as indicated by low-field nuclear magnetic resonance(LF-NMR),magnetic resonance imaging(MRI),and sensory evaluation.The EG/CA-MSN/Zein composite film extended the shelf life of crucian carp fillets by 3-4 days,highlighting its potential as an environmentally friendly and efficient packaging material for aquatic products.
文摘In this study,composite films consisting of polylactic acid(PLA),ethyl cellulose(EC),and zein were prepared by solution casting method,and their performance and application in chilled fresh meat preservation were investigated.The results showed that the three materials had satisfactory compatibility in the composite film.Addition of EC and zein effectively improved the mechanical properties,thermodynamic properties,surface hydrophilicity,oxygen permeability,and degradation properties of PLA films.When the ratio of PLA to EC was 3:7,the tensile strength and elongation at break reached maximum values of 16.6 MPa and 30.5%,respectively.Moreover,under different conditions,the composite film exhibited better degradability than the PLA film.The composite film with a 3:7 ratio of PLA to EC had the best performance,with a degradation rate of 21.75%after 84 days.Chilled fresh meat wrapped with the composite film showed significantly improved antioxidant,antibacterial,and water-holding properties.
文摘Chinese President Xi Jinping calls for honoring history to preserve peace,as the country commemorates the 80th anniversary of its hard-won victory in WWII.
文摘In Maizhokunggar County of Lhasa City,the Xizang Autonomous Region,a precious intangible cultural heritage is preserved-the traditional craft of Zaxoi drum making,which carries profound historical and cultural significance.After hundreds of years,its unique value continues to shine through the passage of time.For more than 40 years,Kongcho Dondrup,an inheritor of this craftsmanship,has poured his heart into preserving and promoting this ancient art.
基金financially supported by the National Key Research and Development Program of China(2022YFC2100800)the National Natural Science Foundation of China(22478296,22078238,52373117,and U23B20121)+1 种基金the Haihe Laboratory of Sustainable Chemical Transformations(24HHWCSS00005)the Open Funding Project of the National Key Laboratory of Biochemical Engineering。
文摘Recent advances in organ transplantation,regenerative medicine,and drug discovery have emphasized the critical importance of effective preservation techniques for organs.Despite these advances,current preservation techniques have significant limitations in maintaining the viability and functional efficacy of organs over the long term.As a result,there is a pressing need to develop reliable and efficient preservation strategies for organs.Currently,the clinical standard for organ preservation involves the use of static cold storage and organ machine perfusion,but these methods can only preserve organs for a couple of days or even a few hours.Notably,the development of cryobiology has yielded promising alternatives.In this review,we aim to provide a comprehensive overview of the progression of organ preservation methods,while emphasizing the limitations of traditional approaches.Moreover,we evaluate advanced preservation techniques for organs,including kidneys,livers,hearts,lungs,and intestines.Furthermore,we share a progress perspective on the future of organ preservation,with the ultimate goal of achieving viable long-term preservation to address the pressing issue of organ shortage.
文摘A precious heritage from ancient times,the Beijing-Hangzhou Grand Canal has renewed its former glory through ecological rehabilitation and cultural preservation over the past decades.
基金supported by the National Key Research&Development Programof China,Ministry of Science and Technology(Nos.2022YFE0134900 and 2022YFC3703200)the Key Research and Development Programof Zhejiang Province,China(No.2024C03228)the National Nature Science Foundation of China(Nos.22376184 and 22076166).
文摘There is growing concern about the concept that exposure to environmental chemicals may be contributing to the obesity epidemic.However,there is no consensus on the obesogenic effects of emerging contaminants from a toxicological and environmental perspective.The potential human exposure and experimental evidence for obesogenic effects of emerging contaminants need to be systematically discussed.The main objective of this review is to provide recommendations for further subsequent policy development following a critical analysis of the literature for humans and experimental animals exposed to emerging contaminants.This article reviews human exposure to emerging contaminants(with a focus on antimicrobials,preservatives,water and oil repellents,flame retardants,antibiotics and bisphenols)and the impact of emerging contaminants on obesity.These emerging contaminants have been widely detected in human biological samples.Epidemiological studies provide evidence linking exposure to emerging contaminants to the risks of obesity in humans.Studies based on animalmodels and adipose cells show the obesogenic effects of emerging contaminants and identify modes of action by which contaminants may induce changes in body fat accumulation and lipid metabolic homeostasis.Some knowledge gaps in this area and future directions for further investigation are discussed.
基金supported by the National Natural Science Foundation of China(Grant Nos.32302170&32172255)HZAU-AGIS Cooperation Fund(Grant No.SZYJY2023001)。
文摘Decays resulting from infections by Geotrichum citri-aurantii cause a significant reduction in citrus postharvest quality and marketable yield.In the present work,0.8 mol·L^(-1)NaCl of Generally Recognized as Safe(GRAS)salts were identified to have complete inhibition activity to G.citriaurantii in vitro and in vivo.An inhibitory mechanism study showed that 0.1 mol·L^(-1)NaCl changed the expression of six genes(Gci002087,Gci003354,Gci000013,Gci000394,Gci003505 and Gci004433)in target of rapamycin(TOR)pathway,thus inducing a large number of lipid droplets(LDs)accumulation with TEM observations and staining.In vivo,0.1 mol·L^(-1)NaCl could raise up the activities of CAT,PAL,PPO and cellulase which hence to strengthen the ability of resistance tolerance of citrus.In addition,NaCl not only accelerated the growth of the biocontrol yeast Kloeckera apiculata strain 34-9,but also increased the expression level of adhesin-encoding genes and biofilm-formation encoding gene(34-9-3691).Finally,the storage experiments in 3 months demonstrated that the combination of NaCl and the yeast 34-9 could keep fresh,reduce decay and prolong its shelf-life,thus implying that the combination of biocontrol strain and GRAS salts has been explored as a promising alternative to synthetic fungicides.
基金Financial support for the current study was provided by the grant from"Blue Engineering"Excellent Young Teacher Foundation in Colleges and Universities of Jiangsu Province(Grant No.KY101R202207 to Xiaojun Chen)。
文摘Premature ovarian insufficiency(POI)caused by chemotherapy is a common complication in female cancer survivors of childbearing age.Traditional methods,including mesenchymal stem cell(MSC)transplant and hormone replacement therapy,have limited clinical application because of their drawbacks,and more methods need to be developed.In the current study,the potential effects and underlying mechanisms of human umbilical cord MSC-derived extracellular vesicles(h UCMSC-EVs)were investigated in a cisplatin(CDDP)-induced POI mouse model and a human granulosa cell(GC)line.The results showed that h UCMSC-EVs significantly attenuated body weight loss,ovarian weight loss,ovary atrophy,and follicle loss in moderate-dose(1.5 mg/kg)CDDP-induced POI mice,similar to the effects observed with h UCMSCs.We further found that the h UCMSCEVs inhibited CDDP-induced ovarian GC apoptosis by upregulating anti-apoptotic mi RNA levels in GCs,thereby downregulating the m RNA levels of multiple pro-apoptotic genes.In general,our findings indicate that the moderate-dose chemotherapy may be a better choice for clinical oncotherapy,considering effective rescue of the oncotherapy-induced ovarian damage with h UCMSC-EVs.Additionally,multiple mi RNAs in h UCMSC-EVs may potentially be used to inhibit the chemotherapy-induced ovarian GC apoptosis,thereby restoring ovarian function and improving the life quality of female cancer patients.
基金financially supported by Natural Science Foundations of Hebei Province(C2022208003)Youth Top Talent Plan in Hebei Province。
文摘Mold spoilage and nutrition enrichment are major concerns of Chinese steamed bread,and using functional lactic acid bacteria as starter to play the role of in-situ preservation and nutritional fortification was a promising alternative.Hence,Lactiplantibacillus plantarum P10 capable of inhibiting spoilage microorganisms and producing γ-aminobutyric acid(GABA)(380 mg/L)was screened from Chinese pickle.Metabolomics analysis showed that P10 produced key antimicrobial metabolites mainly including ten organic acids,aldehyde,alkaloid.Besides,P10 might exhibit health beneficial effects such as degrading cholesterol,lowering blood glucose and reducing uric acid due to the production of deoxycholic acid and Ile-Pro-Ile,and the degradation of purine.Finally,the promising application potential of P10 was evidenced in steamed bread with extended shelf life,excellent anti-aging effect,and 24.5-fold enrichment of GABA.Conclusively,this investigation could provide scientific basis for the application of P10 as a functional starter in steamed bread.
文摘悦读·明其义.A legacy of wilderness.荒野的遗产.In an era where urbanization and industrialization are rapidly expanding,nurturing nature has become not just a passion but a professional qualification for many environmentalists and conservationists.Our planet is home to some of the most splendid natural scenery,yet human activities continue to disturb these delicate ecosystems.The responsibility to protect and preserve these wonders lies with each of us,as the consequences of neglect grow increasingly severe.