Corresponding author’s name was incorrectly written as“Dadang Guo”instead of“Dagang Guo”.The correct author name should be“Dagang Guo”.The authors would like to apologise for any inconvenience caused.
Diabetic wounds represent a significant challenge in the medical field,significantly impacting patient quality of life and imposing a heavy burden on healthcare systems.Intelligent hydrogel dressings have attracted si...Diabetic wounds represent a significant challenge in the medical field,significantly impacting patient quality of life and imposing a heavy burden on healthcare systems.Intelligent hydrogel dressings have attracted significant attention in diabetic wound treatment due to their unique properties.This review systematically explores the three main categories of intelligent hydrogels(natural,synthetic,and composite),dissecting their composition,structure,and the mechanisms that enable their intelligent responses.The crucial roles of these dressings in maintaining a moist wound environment,efficiently absorbing exudate,and precisely delivering drugs are expounded.Moreover,their application advantages in combating bacteria and infections,regulating inflammation and immunity,promoting angiogenesis and tissue regeneration,as well as enabling real-time monitoring and personalized treatment,are explored in depth.Additionally,we discuss future research directions and the prospects for personalized precision medicine in diabetic wound care,aiming to inspire innovation and provide a comprehensive theoretical basis for the development of nextgeneration intelligent dressings.展开更多
Chronic wounds resulting from diabetes are among the most common complications in diabetic patients.Attributable to poor local blood circulation and an increased risk of infection,these wounds heal slowly and are diff...Chronic wounds resulting from diabetes are among the most common complications in diabetic patients.Attributable to poor local blood circulation and an increased risk of infection,these wounds heal slowly and are difficult to treat,posing a significant global health challenge.Herein,we achieved the green valorization of waste liquid from the natural clay-derived zeolite synthesis process and utilized it to fabricate metal-loaded aluminosilicate dressings with pronounced wrinkled structures(wrinkled Cu–AS,Ga–AS,and Ce–AS)through simple procedures.展开更多
The healing of diabetic wounds poses a significant healthcare burden due to persistent inflammation,M1 macrophage aggregation,and high glucose levels in the microenvironment.Previous studies have demonstrated that imm...The healing of diabetic wounds poses a significant healthcare burden due to persistent inflammation,M1 macrophage aggregation,and high glucose levels in the microenvironment.Previous studies have demonstrated that immunomodulatory hydrogel dressings can facilitate diabetic wound healing.However,current immunomodulatory hydrogels require costly and complex treatments such as cell therapy and cytokines.Herein,a hierarchical hydrogel dressing with continuous biochemical gradient based on glycyrrhizic acid(GA) was constructed to modulate immunomodulatory processes in diabetic wounds.The hydrogels present many desirable features,such as tunable mechanical properties,broad antibacterial ability,outstanding conductive,transparent,and self-adhesive properties.The resultant hydrogel can promote diabetic wound healing by preventing bacterial infection,promoting macrophage polarization,improving the inflammatory microenvironment,and inducing angiogenesis and neurogenesis.Furthermore,electrical stimulation(ES) can further promote the healing of chronic diabetic wounds,providing valuable guidance for relevant clinical practice.展开更多
Mimicking the hierarchical structure of the skin is one of the most important strategies in skin tissue engineering.Monolayer wound dressings are usually not able to provide several functions at the same time and cann...Mimicking the hierarchical structure of the skin is one of the most important strategies in skin tissue engineering.Monolayer wound dressings are usually not able to provide several functions at the same time and cannot meet all clinical needs.In order to maximize therapeutic efficiency,herein,we fabricated a Tri-layer wound dressing,where the middle layer was fabricated via 3D-printing and composed of alginate,tragacanth and zinc oxide nanoparticles(ZnO NPs).Both upper and bottom layers were constructed using electrospinning technique;the upper layer was made of hydrophobic polycaprolactone to mimic epidermis,while the bottom layer consisted of Soluplus■ and insulin-like growth factor-1(IGF-1)to promote cell behavior.Swelling,water vapor permeability and tensile properties of the dressings were evaluated and the Tri-layer dressing exhibited impressive antibacterial activity and cell stimulation following by the release of ZnO NPs and IGF-1.Additionally,the Tri-layer dressing led to faster healing of full-thicknesswound in ratmodel compared to monolayer and Bilayer dressings.Overall,the evidence confirmed that the Trilayer wound dressing is extremely effective for full-thickness wound healing.展开更多
BACKGROUND Aloe vera has been used as a traditional herbal therapy for wound management and dermatological conditions worldwide for thousands of years.Scientific evidence has confirmed that acemannan,the bioactive com...BACKGROUND Aloe vera has been used as a traditional herbal therapy for wound management and dermatological conditions worldwide for thousands of years.Scientific evidence has confirmed that acemannan,the bioactive compound in aloe vera gel,exhibits significant anti-inflammatory and immunomodulatory properties that enhance tissue regeneration.This case report describes the successful application of an innovative acemannan-enriched glycolipid sphere dressing derived from aloe vera gel in diabetic foot ulcer(DFU)treatment,which achieved a clinically remarkable outcome.CASE SUMMARY An 80-year-old female patient with a 20-year history of type 2 diabetes mellitus experienced recurrent diabetic foot pain for 15 years.She had multiple hospitalizations due to acute infections and poorly controlled hyperglycemia.Long-term treatments included metformin and gliclazide.Upon presentation,she had a nonhealing wound on her left dorsal foot,diagnosed as a severe DFU(Texas classification:Grade II,stage D).She declined amputation and opted for conservative treatment.The medical team applied an acemannan-enriched glycolipid sphere dressing five times daily to the left calf and foot,avoiding the wound area.Frequency was reduced to three times daily after scab formation.Weight-bearing on the injured foot was avoided.Through in-person and online consultations,the team managed her lifestyle and diet,emphasizing natural foods.After 5 months,the DFU healed without significant scarring or functional loss.No recurrence was observed during the 2-year follow-up.Acemannan-enriched glycolipid sphere dressings promote DFU healing.This suggests the potential of these dressings for treating other refractory wounds.展开更多
The treatment of chronic wounds presents significant challenges due to the necessity of accelerating healing within complex microenvironments characterized by persistent inflammation and biochemical imbalances.Factors...The treatment of chronic wounds presents significant challenges due to the necessity of accelerating healing within complex microenvironments characterized by persistent inflammation and biochemical imbalances.Factors such as bacterial infections,hyperglycemia,and oxidative stress disrupt cellular functions and impair angiogenesis,substantially delaying wound repair.Nanozymes,which are engineered nanoscale materials with enzyme-like activities,offer distinct advantages over conventional enzymes and traditional nanomaterials,making them promising candidates for chronic wound treatment.To enhance their clinical potential,nanozyme-based catalytic systems are currently being optimized through formulation advancements and preclinical studies assessing their biocompatibility,anti-oxidant activity,antibacterial efficacy,and tissue repair capabilities,ensuring their safety and clinical applicability.When integrated into multifunctional wound dressings,nanozymes modulate reactive oxygen species levels,promote tissue regeneration,and simultaneously combat infections and oxidative damage,extending beyond conventional enzyme-like catalysis in chronic wound treatment.The customizable architectures of nanozymes enable precise therapeutic applications,enhancing their effectiveness in managing complex wound conditions.This review provides a comprehensive analysis of the incorporation of nanozymes into wound dressings,detailing fabrication methods and emphasizing their transformative potential in chronic wound management.By identifying and addressing key limitations,we introduce strategic advancements to drive the development of nanozyme-driven dressings,paving the way for next-generation chronic wound treatments.展开更多
Diabetic wounds(DWs)are a major complication of diabetes mellitus,characterized by a complex patho-physiological microenvironment that is associated with elevated morbidity and mortality.Conventional management strate...Diabetic wounds(DWs)are a major complication of diabetes mellitus,characterized by a complex patho-physiological microenvironment that is associated with elevated morbidity and mortality.Conventional management strategies often fail to address the multifaceted nature of these wounds effectively.Recent advancements in understanding the mechanisms of DW healing have spurred the development of a plethora of bioactive dressings designed to interact with and modulate the DW microenvironment.These innovations have culminated in the introduction of the“microenvironment-sensitive with on-demand management”paradigm aimed at delivering precision therapy responsive to dynamic changes within DW.Despite these advancements,the current literature lacks a comprehensive review that cate-gorizes and evaluates active,passive,and on-demand approaches that address the DW microenviron-ment.Herein,we describe the unique pathogenic mechanisms and microenvironmental characteristics that distinguish DW from normal acute wounds.This review provides an extensive overview of contem-porary active and passive management strategies incorporating on-demand management principles designed for DW microenvironments.Furthermore,it addresses the principal challenges faced in this therapeutic domain and outlines the potential innovations that can enhance the efficacy and specificity of bioactive dressings.The insights presented here aim to guide further research and development in the on-demand management of DW to improve patient outcomes by aligning personalized therapy modali-ties with the pathophysiological realities of DW.展开更多
Simulating U(1) quantum gauge theories with spatial dimensions greater than one is of great physical significance. Here we propose a simple realization of U(1) gauge theory with Rydberg and Rydberg-dressed atom arrays...Simulating U(1) quantum gauge theories with spatial dimensions greater than one is of great physical significance. Here we propose a simple realization of U(1) gauge theory with Rydberg and Rydberg-dressed atom arrays. Within the experimentally accessible range, we find that the various aspects of the U(1) gauge theory can be well simulated, such as the emergence of topological sectors, incommensurability, and the Rokhsar–Kivelson point that hosts deconfined charge excitations and degenerate topological sectors. Our proposal is promising to implement experimentally and exhibits pronounced quantum dynamics.展开更多
The aim of this study was to evaluate the cost and effectiveness of soft silicone foam dressings （SSFD, Mepilex） on the treatment of pressure ulcers. We searched electronic databases and retrieved articles to make a...The aim of this study was to evaluate the cost and effectiveness of soft silicone foam dressings （SSFD, Mepilex） on the treatment of pressure ulcers. We searched electronic databases and retrieved articles to make a systematic evaluation, and then make a cost-effectiveness analysis by decision tree model combined with data from clinical treatments. The result shows that compared with the common sterile gauze, SSFD possesses an apparent advantage. The effective ratio is 96.3% versus 77.3%, although the cost of SSFD is much higher than that of sterile gauze, Mepilex appears to be more cost-effectiveness for preventive use.展开更多
The existing studies, concerning the dressing process, focus on the major influence of the dressing conditions on the grinding response variables. However, the choice of the dressing conditions is often made, based on...The existing studies, concerning the dressing process, focus on the major influence of the dressing conditions on the grinding response variables. However, the choice of the dressing conditions is often made, based on the experience of the qualified staff or using data from reference books. The optimal dressing parameters, which are only valid for the particular methods and dressing and grinding conditions, are also used. The paper presents a methodology for optimization of the dressing parameters in cylindrical grinding. The generalized utility function has been chosen as an optimization parameter. It is a complex indicator determining the economic, dynamic and manufacturing characteristics of the grinding process. The developed methodology is implemented for the dressing of aluminium oxide grinding wheels by using experimental diamond roller dressers with different grit sizes made of medium- and high-strength synthetic diamonds type AC32 and AC80. To solve the optimization problem, a model of the generalized utility function is created which reflects the complex impact of dressing parameters. The model is built based on the results from the conducted complex study and modeling of the grinding wheel lifetime, cutting ability, production rate and cutting forces during grinding. They are closely related to the dressing conditions （dressing speed ratio, radial in-feed of the diamond roller dresser and dress-out time）, the diamond roller dresser grit size/grinding wheel grit size ratio, the type of synthetic diamonds and the direction of dressing. Some dressing parameters are determined for which the generalized utility fimction has a maximum and which guarantee an optimum combination of the following： the lifetime and cutting ability of the abrasive wheels, the tangential cutting force magnitude and the production rate of the grinding process. The results obtained prove the possibility of control and optimization of grinding by selecting particular dressing parameters.展开更多
A hydrogel dressing based on bacterial cellulose(BC),which is grafted with quaternary ammonium func-tional and crosslinked with the gelatin-heparin system,is prepared to provide the features mainly con-cerning softnes...A hydrogel dressing based on bacterial cellulose(BC),which is grafted with quaternary ammonium func-tional and crosslinked with the gelatin-heparin system,is prepared to provide the features mainly con-cerning softness,high swelling ratio,antibacterial property,and biocompatibility.An innovation of prepa-ration is that the BC is beaten into short-chain scaffolds to improve the efficiency of grafting,which not only simplifies the preparation process but also avoids the biotoxicity caused by the introduction of toxic catalyst such as dimethyl sulfoxide(DMSO)or uncertain toxic side products in long-chain graft-ing.Scanning electron microscopy(SEM)shows that the QBC/Hep/Gel composite hydrogel possesses a three-dimensional mesh structure with high porosity.The hydrogel shows outstanding water manage-ment performance indicated by the swelling ratio of 1476%,water retention ratio of more than 90%at 120 h,and moisture permeability of 3296 g m^(-2) 24 h^(-1).The antibacterial experiment is implemented with staphylococcus aureus,and the antibacterial effect is represented by an inhibition zone of 3 cm in diameter.In vivo animal experiments suggested that QBC/Hep/Gel could effectively promote epithelial reconstruction,collagen deposition,and angiogenesis in normal wounds,reduce inflammation,and ac-celerate wound healing.All these results indicate that the proposed QBC/Hep/Gel hydrogel is a potential composite for antibacterial dressing.展开更多
Cubic boron nitride(cBN)grinding wheels play a pivotal role in precision machining,serving as indispensable tools for achieving exceptional surface quality.Ensuring the sharpness of cBN grains and optimizing the grind...Cubic boron nitride(cBN)grinding wheels play a pivotal role in precision machining,serving as indispensable tools for achieving exceptional surface quality.Ensuring the sharpness of cBN grains and optimizing the grinding wheel’s chip storage capacity are critical factors.This paper presents a study on the metal-bonded segments and single cBN grain samples using the vacuum sintering method.It investigates the impact of blasting parameters-specifically silicon carbide(SiC)abrasive size,blasting distance,and blasting time-on the erosive wear characteristics of both the metal bond and abrasive.The findings indicate that the abrasive size and blasting distance significantly affect the erosive wear performance of the metal bond.Following a comprehensive analysis of the material removal rate of the metal bond and the erosive wear condition of cBN grains,optimal parameters for the working layer are determined:a blasting distance of 60 mm,a blasting time of 15 s,and SiC particle size of 100#.Furthermore,an advanced simulation model investigates the dressing process of abrasive blasting,revealing that the metal bond effectively inhibits crack propagation within cBN abrasive grains,thereby enhancing fracture toughness and impact resistance.Additionally,a comparative analysis is conducted between the grinding performance of porous cBN grinding wheels and vitrified cBN grinding wheels.The results demonstrate that using porous cBN grinding wheels significantly reduces grinding force,temperature,and chip adhesion,thereby enhancing the surface quality of the workpiece.展开更多
文摘Corresponding author’s name was incorrectly written as“Dadang Guo”instead of“Dagang Guo”.The correct author name should be“Dagang Guo”.The authors would like to apologise for any inconvenience caused.
文摘Diabetic wounds represent a significant challenge in the medical field,significantly impacting patient quality of life and imposing a heavy burden on healthcare systems.Intelligent hydrogel dressings have attracted significant attention in diabetic wound treatment due to their unique properties.This review systematically explores the three main categories of intelligent hydrogels(natural,synthetic,and composite),dissecting their composition,structure,and the mechanisms that enable their intelligent responses.The crucial roles of these dressings in maintaining a moist wound environment,efficiently absorbing exudate,and precisely delivering drugs are expounded.Moreover,their application advantages in combating bacteria and infections,regulating inflammation and immunity,promoting angiogenesis and tissue regeneration,as well as enabling real-time monitoring and personalized treatment,are explored in depth.Additionally,we discuss future research directions and the prospects for personalized precision medicine in diabetic wound care,aiming to inspire innovation and provide a comprehensive theoretical basis for the development of nextgeneration intelligent dressings.
基金financially supported by the start-up research grant from Wuhan University(China)。
文摘Chronic wounds resulting from diabetes are among the most common complications in diabetic patients.Attributable to poor local blood circulation and an increased risk of infection,these wounds heal slowly and are difficult to treat,posing a significant global health challenge.Herein,we achieved the green valorization of waste liquid from the natural clay-derived zeolite synthesis process and utilized it to fabricate metal-loaded aluminosilicate dressings with pronounced wrinkled structures(wrinkled Cu–AS,Ga–AS,and Ce–AS)through simple procedures.
基金supported by Natural Science Foundation of Jilin Province(No.SKL202302002)。
文摘The healing of diabetic wounds poses a significant healthcare burden due to persistent inflammation,M1 macrophage aggregation,and high glucose levels in the microenvironment.Previous studies have demonstrated that immunomodulatory hydrogel dressings can facilitate diabetic wound healing.However,current immunomodulatory hydrogels require costly and complex treatments such as cell therapy and cytokines.Herein,a hierarchical hydrogel dressing with continuous biochemical gradient based on glycyrrhizic acid(GA) was constructed to modulate immunomodulatory processes in diabetic wounds.The hydrogels present many desirable features,such as tunable mechanical properties,broad antibacterial ability,outstanding conductive,transparent,and self-adhesive properties.The resultant hydrogel can promote diabetic wound healing by preventing bacterial infection,promoting macrophage polarization,improving the inflammatory microenvironment,and inducing angiogenesis and neurogenesis.Furthermore,electrical stimulation(ES) can further promote the healing of chronic diabetic wounds,providing valuable guidance for relevant clinical practice.
基金support of Isfahan University of Medical Sciences(Project code No.#1401262).
文摘Mimicking the hierarchical structure of the skin is one of the most important strategies in skin tissue engineering.Monolayer wound dressings are usually not able to provide several functions at the same time and cannot meet all clinical needs.In order to maximize therapeutic efficiency,herein,we fabricated a Tri-layer wound dressing,where the middle layer was fabricated via 3D-printing and composed of alginate,tragacanth and zinc oxide nanoparticles(ZnO NPs).Both upper and bottom layers were constructed using electrospinning technique;the upper layer was made of hydrophobic polycaprolactone to mimic epidermis,while the bottom layer consisted of Soluplus■ and insulin-like growth factor-1(IGF-1)to promote cell behavior.Swelling,water vapor permeability and tensile properties of the dressings were evaluated and the Tri-layer dressing exhibited impressive antibacterial activity and cell stimulation following by the release of ZnO NPs and IGF-1.Additionally,the Tri-layer dressing led to faster healing of full-thicknesswound in ratmodel compared to monolayer and Bilayer dressings.Overall,the evidence confirmed that the Trilayer wound dressing is extremely effective for full-thickness wound healing.
文摘BACKGROUND Aloe vera has been used as a traditional herbal therapy for wound management and dermatological conditions worldwide for thousands of years.Scientific evidence has confirmed that acemannan,the bioactive compound in aloe vera gel,exhibits significant anti-inflammatory and immunomodulatory properties that enhance tissue regeneration.This case report describes the successful application of an innovative acemannan-enriched glycolipid sphere dressing derived from aloe vera gel in diabetic foot ulcer(DFU)treatment,which achieved a clinically remarkable outcome.CASE SUMMARY An 80-year-old female patient with a 20-year history of type 2 diabetes mellitus experienced recurrent diabetic foot pain for 15 years.She had multiple hospitalizations due to acute infections and poorly controlled hyperglycemia.Long-term treatments included metformin and gliclazide.Upon presentation,she had a nonhealing wound on her left dorsal foot,diagnosed as a severe DFU(Texas classification:Grade II,stage D).She declined amputation and opted for conservative treatment.The medical team applied an acemannan-enriched glycolipid sphere dressing five times daily to the left calf and foot,avoiding the wound area.Frequency was reduced to three times daily after scab formation.Weight-bearing on the injured foot was avoided.Through in-person and online consultations,the team managed her lifestyle and diet,emphasizing natural foods.After 5 months,the DFU healed without significant scarring or functional loss.No recurrence was observed during the 2-year follow-up.Acemannan-enriched glycolipid sphere dressings promote DFU healing.This suggests the potential of these dressings for treating other refractory wounds.
基金supported by the Key Project of the Joint Fund for Regional Innovation and Development of the National Natural Science Foundation of China(U23A20686)the National Natural Science Foundation of China(81901979)+2 种基金the Peking University People’s Hospital Scientific Research Development Funds(RDJP2022-07)the Joint Funds for the Innovation of Science and Technology,Fujian Province(2023Y9226)the Introduced High-Level Talent Team Project of Quanzhou City(2023CT008).
文摘The treatment of chronic wounds presents significant challenges due to the necessity of accelerating healing within complex microenvironments characterized by persistent inflammation and biochemical imbalances.Factors such as bacterial infections,hyperglycemia,and oxidative stress disrupt cellular functions and impair angiogenesis,substantially delaying wound repair.Nanozymes,which are engineered nanoscale materials with enzyme-like activities,offer distinct advantages over conventional enzymes and traditional nanomaterials,making them promising candidates for chronic wound treatment.To enhance their clinical potential,nanozyme-based catalytic systems are currently being optimized through formulation advancements and preclinical studies assessing their biocompatibility,anti-oxidant activity,antibacterial efficacy,and tissue repair capabilities,ensuring their safety and clinical applicability.When integrated into multifunctional wound dressings,nanozymes modulate reactive oxygen species levels,promote tissue regeneration,and simultaneously combat infections and oxidative damage,extending beyond conventional enzyme-like catalysis in chronic wound treatment.The customizable architectures of nanozymes enable precise therapeutic applications,enhancing their effectiveness in managing complex wound conditions.This review provides a comprehensive analysis of the incorporation of nanozymes into wound dressings,detailing fabrication methods and emphasizing their transformative potential in chronic wound management.By identifying and addressing key limitations,we introduce strategic advancements to drive the development of nanozyme-driven dressings,paving the way for next-generation chronic wound treatments.
基金supported by the National Natural Science Foundation of China(22408078,82401057,32101170)the Zhejiang Province Postdoctoral Excellence Funding Program-Special Support(ZJ2024004).
文摘Diabetic wounds(DWs)are a major complication of diabetes mellitus,characterized by a complex patho-physiological microenvironment that is associated with elevated morbidity and mortality.Conventional management strategies often fail to address the multifaceted nature of these wounds effectively.Recent advancements in understanding the mechanisms of DW healing have spurred the development of a plethora of bioactive dressings designed to interact with and modulate the DW microenvironment.These innovations have culminated in the introduction of the“microenvironment-sensitive with on-demand management”paradigm aimed at delivering precision therapy responsive to dynamic changes within DW.Despite these advancements,the current literature lacks a comprehensive review that cate-gorizes and evaluates active,passive,and on-demand approaches that address the DW microenviron-ment.Herein,we describe the unique pathogenic mechanisms and microenvironmental characteristics that distinguish DW from normal acute wounds.This review provides an extensive overview of contem-porary active and passive management strategies incorporating on-demand management principles designed for DW microenvironments.Furthermore,it addresses the principal challenges faced in this therapeutic domain and outlines the potential innovations that can enhance the efficacy and specificity of bioactive dressings.The insights presented here aim to guide further research and development in the on-demand management of DW to improve patient outcomes by aligning personalized therapy modali-ties with the pathophysiological realities of DW.
基金supported by the National Key Research and Development Program of China (Grant Nos. 2022YFA1404204 and 2022YFA1403700)the National Natural Science Foundation of China (Grant Nos. 12274086, 11534001 and 11925402)+5 种基金funding from the National Science Foundation of China (Grant Nos. 12274046, 11874094, 12147102, and 12347101)Chongqing Natural Science Foundation (Grant No. CSTB2022NSCQ-JQX0018)the Fundamental Research Funds for the Central Universities (Grant No. 2021CDJZYJH-003)Xiaomi Foundation/Xiaomi Young Talents Programthe supports of the start-up funding of Westlake Universitysupport from the Natural Sciences and Engineering Research Council of Canada (NSERC) through Discovery Grants。
文摘Simulating U(1) quantum gauge theories with spatial dimensions greater than one is of great physical significance. Here we propose a simple realization of U(1) gauge theory with Rydberg and Rydberg-dressed atom arrays. Within the experimentally accessible range, we find that the various aspects of the U(1) gauge theory can be well simulated, such as the emergence of topological sectors, incommensurability, and the Rokhsar–Kivelson point that hosts deconfined charge excitations and degenerate topological sectors. Our proposal is promising to implement experimentally and exhibits pronounced quantum dynamics.
基金Mlnlycke Health Care for their assistance on this project
文摘The aim of this study was to evaluate the cost and effectiveness of soft silicone foam dressings （SSFD, Mepilex） on the treatment of pressure ulcers. We searched electronic databases and retrieved articles to make a systematic evaluation, and then make a cost-effectiveness analysis by decision tree model combined with data from clinical treatments. The result shows that compared with the common sterile gauze, SSFD possesses an apparent advantage. The effective ratio is 96.3% versus 77.3%, although the cost of SSFD is much higher than that of sterile gauze, Mepilex appears to be more cost-effectiveness for preventive use.
文摘The existing studies, concerning the dressing process, focus on the major influence of the dressing conditions on the grinding response variables. However, the choice of the dressing conditions is often made, based on the experience of the qualified staff or using data from reference books. The optimal dressing parameters, which are only valid for the particular methods and dressing and grinding conditions, are also used. The paper presents a methodology for optimization of the dressing parameters in cylindrical grinding. The generalized utility function has been chosen as an optimization parameter. It is a complex indicator determining the economic, dynamic and manufacturing characteristics of the grinding process. The developed methodology is implemented for the dressing of aluminium oxide grinding wheels by using experimental diamond roller dressers with different grit sizes made of medium- and high-strength synthetic diamonds type AC32 and AC80. To solve the optimization problem, a model of the generalized utility function is created which reflects the complex impact of dressing parameters. The model is built based on the results from the conducted complex study and modeling of the grinding wheel lifetime, cutting ability, production rate and cutting forces during grinding. They are closely related to the dressing conditions （dressing speed ratio, radial in-feed of the diamond roller dresser and dress-out time）, the diamond roller dresser grit size/grinding wheel grit size ratio, the type of synthetic diamonds and the direction of dressing. Some dressing parameters are determined for which the generalized utility fimction has a maximum and which guarantee an optimum combination of the following： the lifetime and cutting ability of the abrasive wheels, the tangential cutting force magnitude and the production rate of the grinding process. The results obtained prove the possibility of control and optimization of grinding by selecting particular dressing parameters.
基金Science and Technology Program of Shaanxi Province(No.2019GY-200).
文摘A hydrogel dressing based on bacterial cellulose(BC),which is grafted with quaternary ammonium func-tional and crosslinked with the gelatin-heparin system,is prepared to provide the features mainly con-cerning softness,high swelling ratio,antibacterial property,and biocompatibility.An innovation of prepa-ration is that the BC is beaten into short-chain scaffolds to improve the efficiency of grafting,which not only simplifies the preparation process but also avoids the biotoxicity caused by the introduction of toxic catalyst such as dimethyl sulfoxide(DMSO)or uncertain toxic side products in long-chain graft-ing.Scanning electron microscopy(SEM)shows that the QBC/Hep/Gel composite hydrogel possesses a three-dimensional mesh structure with high porosity.The hydrogel shows outstanding water manage-ment performance indicated by the swelling ratio of 1476%,water retention ratio of more than 90%at 120 h,and moisture permeability of 3296 g m^(-2) 24 h^(-1).The antibacterial experiment is implemented with staphylococcus aureus,and the antibacterial effect is represented by an inhibition zone of 3 cm in diameter.In vivo animal experiments suggested that QBC/Hep/Gel could effectively promote epithelial reconstruction,collagen deposition,and angiogenesis in normal wounds,reduce inflammation,and ac-celerate wound healing.All these results indicate that the proposed QBC/Hep/Gel hydrogel is a potential composite for antibacterial dressing.
基金Supported by National Natural Science Foundation of China(Grant Nos.92160301,92060203,52175415,52205475,and 52205493)Science Center for Gas Turbine Project(Grant Nos.P2022-AB-IV-002-001 and P2023-B-IV-003-001)+3 种基金Jiangsu Provincial Natural Science Foundation(Grant No.BK20210295)the Huaqiao University Engineering Research Center of Brittle Materials Machining(Grant No.2023IME-001)Foundation of Graduate Innovation Centre in NUAA(Grant No.XCXJH20230509)Fundamental Research Funds for the Central Universities(Grant Nos.NS2023028 and NG2024015).
文摘Cubic boron nitride(cBN)grinding wheels play a pivotal role in precision machining,serving as indispensable tools for achieving exceptional surface quality.Ensuring the sharpness of cBN grains and optimizing the grinding wheel’s chip storage capacity are critical factors.This paper presents a study on the metal-bonded segments and single cBN grain samples using the vacuum sintering method.It investigates the impact of blasting parameters-specifically silicon carbide(SiC)abrasive size,blasting distance,and blasting time-on the erosive wear characteristics of both the metal bond and abrasive.The findings indicate that the abrasive size and blasting distance significantly affect the erosive wear performance of the metal bond.Following a comprehensive analysis of the material removal rate of the metal bond and the erosive wear condition of cBN grains,optimal parameters for the working layer are determined:a blasting distance of 60 mm,a blasting time of 15 s,and SiC particle size of 100#.Furthermore,an advanced simulation model investigates the dressing process of abrasive blasting,revealing that the metal bond effectively inhibits crack propagation within cBN abrasive grains,thereby enhancing fracture toughness and impact resistance.Additionally,a comparative analysis is conducted between the grinding performance of porous cBN grinding wheels and vitrified cBN grinding wheels.The results demonstrate that using porous cBN grinding wheels significantly reduces grinding force,temperature,and chip adhesion,thereby enhancing the surface quality of the workpiece.
