Photothermal therapy(PTT)is a desirable way to attain on-demand hyperthermia owing to the heat gen-erated by photothermal materials absorbing near-infrared light.The mild heat(42±0.5℃)can not only accelerate bon...Photothermal therapy(PTT)is a desirable way to attain on-demand hyperthermia owing to the heat gen-erated by photothermal materials absorbing near-infrared light.The mild heat(42±0.5℃)can not only accelerate bone tissue regeneration but also promote the release of bioactive ions from biomaterials.Based on this one-stone-two-birds strategy,a 3D printed PEEK-graphene composite scaffold(PG)with hydroxyapatite(HA)coating(PGH)for photothermally remote control of bone regeneration was well de-signed in this study.The results showed that the HA coating on PGH could release Ca^(2+)and PO_(4)^(3-)ions easily under NIR irradiation,which was ascribed to the mild heat generated from graphene in the com-posite scaffold.The mild heat and the boosted Ca^(2+)/PO_(4)^(3-)release could synergistically enhance the bone regeneration ability both in vitro and in vivo.The underlying mechanism was further explored and con-firmed to be closely related to the upregulation of HSP 70,by which the MAPK/ERK signaling pathway was activated selectively.The favorable results demonstrate that the 3D-printed PEEK/graphene composite scaffold is promising in the applications of bone defect repair.展开更多
Increasing consumer awareness regarding the health benefits of different nutrients in food has led to the requirement of assessing the effect of food processing approaches on the quality attributes. The present work f...Increasing consumer awareness regarding the health benefits of different nutrients in food has led to the requirement of assessing the effect of food processing approaches on the quality attributes. The present work focuses on understanding the effects of ultrasound (US) processing, mild heat pasteurization (65°C for 15 min), thermal pasteurization (80°C for 15 min) and their combination on physicochemical, microbiological properties and nutritional quality of pineapple juice through 60 days of storage at room temperature. Ultrasound treatment showed significantly lower browning degree. Ultrasound followed by ultrasound combined with mild heat pasteurization (UMP) treatments was effective in retaining the total phenolic content of pineapple juice as compared to the thermal treatment or the untreated juice sample at room temperature during 60 days of storage. Thermal pasteurization (TP) followed by ultrasound combined with mild heat pasteurization (UMP) and ultrasound (US) treatment, in increasing order, was found to be effective in delaying microbial growth in pineapple juice. This study demonstrates that ultrasound combined with mild heat pasteurization treatments could be able to effectively inactivate the microorganisms and pectin methylesterase in pineapple juice whilst preserving relatively high amount of phenols.展开更多
This study elucidated the antimicrobial effect of ammonium persulfate(PS),ultrasound(US),and 40-60℃mild heat on Staphylococcus aureus ATCC 27213 under various growth conditions,including non-adaptation,pHadaptation,a...This study elucidated the antimicrobial effect of ammonium persulfate(PS),ultrasound(US),and 40-60℃mild heat on Staphylococcus aureus ATCC 27213 under various growth conditions,including non-adaptation,pHadaptation,and aridity-adaptation,in buffered peptone water(BPW)and on orange peel surfaces.For nonadapted,pH-adapted,and aridity-adapted S.aureus,the combined treatment of PS,US,and mild heat showed a synergistic effect,with log reductions of 2.05,6.44,and 1.11 log CFU/mL in BPW after 6 min,respectively.Mechanistic experiments showed that pH-adapted S.aureus had increased SOD activity due to oxidative stress from the acidic environment,but the introduction of PS further elevated this stress,leading to greater cell death primarily through membrane damage,as confirmed by TEM,with leakage of nucleic acids and proteins.This technique was applied to an orange peel washing system,effectively inactivating aridity-adapted S.aureus,resulting in 3.51 log CFU/cm^(2)and 3.20 log CFU/mL reductions on orange peel and in BPW washing water,respectively,after a 6-min treatment,without any quality changes,including color and texture attributes.The enhanced inactivation on orange peel may be attributed to the presence of compounds such as ascorbic acid and limonene,which further activate persulfate and exhibit antimicrobial properties,thereby contributing to the increased efficacy of the treatment.The combined PS,US,and mild heat treatment provides an effective strategy for controlling resilient bacterial strains in the food industry,enhancing food safety through oxidative stress and mild thermal effects.展开更多
Hurdle technology,which integrates multiple preservation methods,is gaining attention as a means to enhance microbiological food safety.This study investigated the synergistic antimicrobial effect of syringic acid(SA)...Hurdle technology,which integrates multiple preservation methods,is gaining attention as a means to enhance microbiological food safety.This study investigated the synergistic antimicrobial effect of syringic acid(SA)and mild heat(MH)against four major foodborne pathogens(Escherichia coli O157:H7,Salmonella enterica serovar Typhimurium,Listeria monocytogenes,and Staphylococcus aureus)in buffer and tomato juice.Treatments were performed using SA(5 mM),MH(50℃),or their combination for up to 20 min.The combined treatment resulted in at least a 5-log reduction in all tested pathogens,showing clear synergistic bactericidal activity compared with individual treatments.Mechanistic analyses revealed that the combined treatment caused greater membrane permeability and loss of metabolic activity,as evidenced by increased propidium iodide uptake,decreased iodonitrotetrazolium chloride reduction,and reduced activities of glycolytic enzymes(hexokinase,phospho-fructokinase,and pyruvate kinase).Importantly,the treatment did not significantly affect key quality parameters of tomato juice,including color and lycopene content.These findings demonstrate that the combination of SA and MH effectively inactivates diverse foodborne pathogens through multi-targeted cellular damage while preserving product quality,suggesting its potential as a practical and natural approach to improve food safety in liquid food matrices.展开更多
Heat exchanger is an important equipment used in process industries for cooling and heating purposes. Its design configuration which involves the flow of cold and hot fluids within the exchanger subjects it to corrosi...Heat exchanger is an important equipment used in process industries for cooling and heating purposes. Its design configuration which involves the flow of cold and hot fluids within the exchanger subjects it to corrosion attack. The article utilized the principle of mass and energy conservation in the development of weight and temperature models to study the effect of corrosion on mild steel coupon inside the exchanger containing water and Mono ethanol amine (MEA). The models developed were resolved analytically using Laplace Transform and simulated using Excel as simulation tool and data obtained from experiment in the laboratory to obtain profiles of weight loss and temperature as a function of time. The weight loss and performance of mild steel under various corrosive conditions were examined which indicates the effect of corrosion on the mild steel heat exchanger in water and MEA media. The result shows that water is more corrosive than MEA at higher temperatures and at lower temperatures of 35°C and 1 atm, MEA has inhibitive properties than water as indicated by the weight loss result with time. The comparative analysis between the results obtained from the model simulation and experimental results shows that the result obtained from the model is more reliable and demonstrated better performance characteristics as it clearly shows mild steel heat exchanger experiences more corrosive effect in water medium than MEA at higher temperatures. And at lower temperatures, MEA becomes more inhibitive and less corrosive than water. The model simulation results correlate with various literatures and hence, it is valid for future referencing.展开更多
The predictability of hardness of the heat affected zone (HAZ) in aluminum weldments cooled in palm oil, based on hardness of similarly cooled mild steel and cast iron weldments has been ascertained. The general mode...The predictability of hardness of the heat affected zone (HAZ) in aluminum weldments cooled in palm oil, based on hardness of similarly cooled mild steel and cast iron weldments has been ascertained. The general model: α = 1.2769? indicates that HAZ hardness of aluminium weldment is dependant on the ratio of product to sum of HAZ hardness of mild steel and cast iron weldments cooled in palm oil under the same conditions. The maximum deviations of the model-predicted HAZ hardness values α, μ and β from the corresponding experimental values αexp, μexp and βexp were less than 0.04% indicating the reliability and validity of the model.展开更多
以某一电站燃煤锅炉为例,对50%综合氧浓度煤粉MILD(Moderate and Low Oxygen Diluted)燃烧锅炉的锅炉效率、烟气辐射特性、炉膛辐射换热计算方法、受热面变化等进行了探索和分析。结果表明:相比空气燃烧方式,50%综合氧浓度煤粉MILD燃烧...以某一电站燃煤锅炉为例,对50%综合氧浓度煤粉MILD(Moderate and Low Oxygen Diluted)燃烧锅炉的锅炉效率、烟气辐射特性、炉膛辐射换热计算方法、受热面变化等进行了探索和分析。结果表明:相比空气燃烧方式,50%综合氧浓度煤粉MILD燃烧方式下的烟气量减小58.6%,锅炉效率提高4.8%,炉膛内烟气发射率提高23%,低温过热器面积和低温再热器面积分别降低82.9%和85%,其他受热面面积都有一定幅度的下降,锅炉总受热面减小58.8%。展开更多
The heat transfer in a steelmaking ladle was studied. The evaluation of heat transfer of the steel was performed by measuring steel temperature in points including all refining steel process. In the ladle, the tempera...The heat transfer in a steelmaking ladle was studied. The evaluation of heat transfer of the steel was performed by measuring steel temperature in points including all refining steel process. In the ladle, the temperatures in the refractories and the shell were also measured. To evaluate the thermal profile between the hot and cold faces of the ladle in the slag line position, an experiment which shows the importance of thermal contact resistance was carried out. Higher heat losses in the tapping and the vacuum were verified. The temperature measurements of the ladle indicate distinct thermal profiles in each stage of steel refining. Moreover, as each stage of the process depends on the previous one, the complexity of the ladle thermal control is incremental. So a complete model of heat losses in the ladle is complex.展开更多
Models have been derived for assessment and computational analysis of the hardness of the heat affected zone (HAZ) in aluminum weldment. The general model;γ = 1.2714[(αβ/α + β)] was found to predict the HAZ hardn...Models have been derived for assessment and computational analysis of the hardness of the heat affected zone (HAZ) in aluminum weldment. The general model;γ = 1.2714[(αβ/α + β)] was found to predict the HAZ hardness of aluminum weldment cooled in water as a function of the HAZ hardness of both mild steel and cast iron welded and cooled under the same conditions. The maximum deviations of the model-predicted HAZ hardness values γ, α and β from the corresponding experimental values γexp, αexp and βexp were less than 0.02% respectively.展开更多
Heat shock proteins (HSPs) serve to correct proteins’ conformation, send the damaged proteins for degradation (quality control function). Heat shock factors (HSFs) are their transcription factors. The protein complex...Heat shock proteins (HSPs) serve to correct proteins’ conformation, send the damaged proteins for degradation (quality control function). Heat shock factors (HSFs) are their transcription factors. The protein complexes mTOR1 and 2 (with the same core mTOR), the phosphoinositide-dependent protein kinase-1 (PDK1), the seine/threonine-specific protein kinase (Akt), HSF1, plus their associated proteins form a network participating in protein synthesis, bio-energy generation, signaling for apoptosis with the help of HSPs. A cancer cell synthesizes proteins at fast rate and needs more HSPs to work on quality control. Shutting down this network would lead to cell death. Thus inhibitors of mTOR (mTORI) and inhibitors of HSPs (HSPI) could drive cancer cell to apoptosis—a “passive approach”. On the other hand, HSPs form complexes with polypeptides characteristic of the cancer cells;on excretion from the cell, they becomes antigens for the immunity cells, eventually leading to maturation of the cytotoxic T cells, forming the basic principle of preparing cancer-specific, person-specific vaccine. Recent finding shows that HSP70 can penetrate cancer cell and expel its analog to extracellular region, giving the hope to prepare a non-person-specific vaccine covering a variety of cancers. Activation of anti-cancer immunity is the “active approach”. On the other hand, mild hyperthermia, with increase of intracellular HSPs, has been found to activate the immunity response, and demonstrate anti-cancer effects. There are certain “mysteries” behind the mechanisms of the active and passive approaches. We analyze the mechanisms involved and provide explanations to some mysteries. We also suggest future research to improve our understanding of these two approaches, in which HSPs play many roles.展开更多
基金supported by grants from the Project funded by the China Postdoctoral Science Foundation(Nos.2023M732469 and 2023M732477)the Sichuan University Postdoctoral Interdisciplinary Innovation Fund(No.JCXK2205)+3 种基金the Projects of the Science and Technology Department of Sichuan Province(Nos.24NSFSC7945,24NSFSC6493,2022ZDZX0029,2023NSFSC0659,MZGC20230019)the National Natural Science Foundation of China(No.52302351)the Sichuan Provincial Medical Association Special Research Fund(Nos.2021SAT05 and 2019HR18)the National Program for Postdoctoral Researchers(No.GZB20230485)as well as the Fundamental Research Funds for the Central Universities(No.2023SCU12116).
文摘Photothermal therapy(PTT)is a desirable way to attain on-demand hyperthermia owing to the heat gen-erated by photothermal materials absorbing near-infrared light.The mild heat(42±0.5℃)can not only accelerate bone tissue regeneration but also promote the release of bioactive ions from biomaterials.Based on this one-stone-two-birds strategy,a 3D printed PEEK-graphene composite scaffold(PG)with hydroxyapatite(HA)coating(PGH)for photothermally remote control of bone regeneration was well de-signed in this study.The results showed that the HA coating on PGH could release Ca^(2+)and PO_(4)^(3-)ions easily under NIR irradiation,which was ascribed to the mild heat generated from graphene in the com-posite scaffold.The mild heat and the boosted Ca^(2+)/PO_(4)^(3-)release could synergistically enhance the bone regeneration ability both in vitro and in vivo.The underlying mechanism was further explored and con-firmed to be closely related to the upregulation of HSP 70,by which the MAPK/ERK signaling pathway was activated selectively.The favorable results demonstrate that the 3D-printed PEEK/graphene composite scaffold is promising in the applications of bone defect repair.
文摘Increasing consumer awareness regarding the health benefits of different nutrients in food has led to the requirement of assessing the effect of food processing approaches on the quality attributes. The present work focuses on understanding the effects of ultrasound (US) processing, mild heat pasteurization (65°C for 15 min), thermal pasteurization (80°C for 15 min) and their combination on physicochemical, microbiological properties and nutritional quality of pineapple juice through 60 days of storage at room temperature. Ultrasound treatment showed significantly lower browning degree. Ultrasound followed by ultrasound combined with mild heat pasteurization (UMP) treatments was effective in retaining the total phenolic content of pineapple juice as compared to the thermal treatment or the untreated juice sample at room temperature during 60 days of storage. Thermal pasteurization (TP) followed by ultrasound combined with mild heat pasteurization (UMP) and ultrasound (US) treatment, in increasing order, was found to be effective in delaying microbial growth in pineapple juice. This study demonstrates that ultrasound combined with mild heat pasteurization treatments could be able to effectively inactivate the microorganisms and pectin methylesterase in pineapple juice whilst preserving relatively high amount of phenols.
基金supported by the New Faculty Startup Fund from Seoul National University.
文摘This study elucidated the antimicrobial effect of ammonium persulfate(PS),ultrasound(US),and 40-60℃mild heat on Staphylococcus aureus ATCC 27213 under various growth conditions,including non-adaptation,pHadaptation,and aridity-adaptation,in buffered peptone water(BPW)and on orange peel surfaces.For nonadapted,pH-adapted,and aridity-adapted S.aureus,the combined treatment of PS,US,and mild heat showed a synergistic effect,with log reductions of 2.05,6.44,and 1.11 log CFU/mL in BPW after 6 min,respectively.Mechanistic experiments showed that pH-adapted S.aureus had increased SOD activity due to oxidative stress from the acidic environment,but the introduction of PS further elevated this stress,leading to greater cell death primarily through membrane damage,as confirmed by TEM,with leakage of nucleic acids and proteins.This technique was applied to an orange peel washing system,effectively inactivating aridity-adapted S.aureus,resulting in 3.51 log CFU/cm^(2)and 3.20 log CFU/mL reductions on orange peel and in BPW washing water,respectively,after a 6-min treatment,without any quality changes,including color and texture attributes.The enhanced inactivation on orange peel may be attributed to the presence of compounds such as ascorbic acid and limonene,which further activate persulfate and exhibit antimicrobial properties,thereby contributing to the increased efficacy of the treatment.The combined PS,US,and mild heat treatment provides an effective strategy for controlling resilient bacterial strains in the food industry,enhancing food safety through oxidative stress and mild thermal effects.
基金supported by the New Faculty Startup Fund from Seoul National University.
文摘Hurdle technology,which integrates multiple preservation methods,is gaining attention as a means to enhance microbiological food safety.This study investigated the synergistic antimicrobial effect of syringic acid(SA)and mild heat(MH)against four major foodborne pathogens(Escherichia coli O157:H7,Salmonella enterica serovar Typhimurium,Listeria monocytogenes,and Staphylococcus aureus)in buffer and tomato juice.Treatments were performed using SA(5 mM),MH(50℃),or their combination for up to 20 min.The combined treatment resulted in at least a 5-log reduction in all tested pathogens,showing clear synergistic bactericidal activity compared with individual treatments.Mechanistic analyses revealed that the combined treatment caused greater membrane permeability and loss of metabolic activity,as evidenced by increased propidium iodide uptake,decreased iodonitrotetrazolium chloride reduction,and reduced activities of glycolytic enzymes(hexokinase,phospho-fructokinase,and pyruvate kinase).Importantly,the treatment did not significantly affect key quality parameters of tomato juice,including color and lycopene content.These findings demonstrate that the combination of SA and MH effectively inactivates diverse foodborne pathogens through multi-targeted cellular damage while preserving product quality,suggesting its potential as a practical and natural approach to improve food safety in liquid food matrices.
文摘Heat exchanger is an important equipment used in process industries for cooling and heating purposes. Its design configuration which involves the flow of cold and hot fluids within the exchanger subjects it to corrosion attack. The article utilized the principle of mass and energy conservation in the development of weight and temperature models to study the effect of corrosion on mild steel coupon inside the exchanger containing water and Mono ethanol amine (MEA). The models developed were resolved analytically using Laplace Transform and simulated using Excel as simulation tool and data obtained from experiment in the laboratory to obtain profiles of weight loss and temperature as a function of time. The weight loss and performance of mild steel under various corrosive conditions were examined which indicates the effect of corrosion on the mild steel heat exchanger in water and MEA media. The result shows that water is more corrosive than MEA at higher temperatures and at lower temperatures of 35°C and 1 atm, MEA has inhibitive properties than water as indicated by the weight loss result with time. The comparative analysis between the results obtained from the model simulation and experimental results shows that the result obtained from the model is more reliable and demonstrated better performance characteristics as it clearly shows mild steel heat exchanger experiences more corrosive effect in water medium than MEA at higher temperatures. And at lower temperatures, MEA becomes more inhibitive and less corrosive than water. The model simulation results correlate with various literatures and hence, it is valid for future referencing.
文摘The predictability of hardness of the heat affected zone (HAZ) in aluminum weldments cooled in palm oil, based on hardness of similarly cooled mild steel and cast iron weldments has been ascertained. The general model: α = 1.2769? indicates that HAZ hardness of aluminium weldment is dependant on the ratio of product to sum of HAZ hardness of mild steel and cast iron weldments cooled in palm oil under the same conditions. The maximum deviations of the model-predicted HAZ hardness values α, μ and β from the corresponding experimental values αexp, μexp and βexp were less than 0.04% indicating the reliability and validity of the model.
文摘以某一电站燃煤锅炉为例,对50%综合氧浓度煤粉MILD(Moderate and Low Oxygen Diluted)燃烧锅炉的锅炉效率、烟气辐射特性、炉膛辐射换热计算方法、受热面变化等进行了探索和分析。结果表明:相比空气燃烧方式,50%综合氧浓度煤粉MILD燃烧方式下的烟气量减小58.6%,锅炉效率提高4.8%,炉膛内烟气发射率提高23%,低温过热器面积和低温再热器面积分别降低82.9%和85%,其他受热面面积都有一定幅度的下降,锅炉总受热面减小58.8%。
文摘The heat transfer in a steelmaking ladle was studied. The evaluation of heat transfer of the steel was performed by measuring steel temperature in points including all refining steel process. In the ladle, the temperatures in the refractories and the shell were also measured. To evaluate the thermal profile between the hot and cold faces of the ladle in the slag line position, an experiment which shows the importance of thermal contact resistance was carried out. Higher heat losses in the tapping and the vacuum were verified. The temperature measurements of the ladle indicate distinct thermal profiles in each stage of steel refining. Moreover, as each stage of the process depends on the previous one, the complexity of the ladle thermal control is incremental. So a complete model of heat losses in the ladle is complex.
文摘Models have been derived for assessment and computational analysis of the hardness of the heat affected zone (HAZ) in aluminum weldment. The general model;γ = 1.2714[(αβ/α + β)] was found to predict the HAZ hardness of aluminum weldment cooled in water as a function of the HAZ hardness of both mild steel and cast iron welded and cooled under the same conditions. The maximum deviations of the model-predicted HAZ hardness values γ, α and β from the corresponding experimental values γexp, αexp and βexp were less than 0.02% respectively.
文摘Heat shock proteins (HSPs) serve to correct proteins’ conformation, send the damaged proteins for degradation (quality control function). Heat shock factors (HSFs) are their transcription factors. The protein complexes mTOR1 and 2 (with the same core mTOR), the phosphoinositide-dependent protein kinase-1 (PDK1), the seine/threonine-specific protein kinase (Akt), HSF1, plus their associated proteins form a network participating in protein synthesis, bio-energy generation, signaling for apoptosis with the help of HSPs. A cancer cell synthesizes proteins at fast rate and needs more HSPs to work on quality control. Shutting down this network would lead to cell death. Thus inhibitors of mTOR (mTORI) and inhibitors of HSPs (HSPI) could drive cancer cell to apoptosis—a “passive approach”. On the other hand, HSPs form complexes with polypeptides characteristic of the cancer cells;on excretion from the cell, they becomes antigens for the immunity cells, eventually leading to maturation of the cytotoxic T cells, forming the basic principle of preparing cancer-specific, person-specific vaccine. Recent finding shows that HSP70 can penetrate cancer cell and expel its analog to extracellular region, giving the hope to prepare a non-person-specific vaccine covering a variety of cancers. Activation of anti-cancer immunity is the “active approach”. On the other hand, mild hyperthermia, with increase of intracellular HSPs, has been found to activate the immunity response, and demonstrate anti-cancer effects. There are certain “mysteries” behind the mechanisms of the active and passive approaches. We analyze the mechanisms involved and provide explanations to some mysteries. We also suggest future research to improve our understanding of these two approaches, in which HSPs play many roles.
