Solid-state bonding between pure titanium and Ti6Al4V(TC4)alloy was conducted by a new bonding method named as rigid restraint thermal self-compressing bonding.Effects of heating time on bonding interface,atom diffusi...Solid-state bonding between pure titanium and Ti6Al4V(TC4)alloy was conducted by a new bonding method named as rigid restraint thermal self-compressing bonding.Effects of heating time on bonding interface,atom diffusion and mechanical properties of the joints were studied.Results show that atom diffusion between pure titanium and TC4 alloy significantly takes place during bonding.The diffusion depths of Al and V in pure titanium side are increased with increasing heating time.Due to the enhancement of atom diffusion,bond quality of the bonding interface is improved along with the increase of heating time.The heating time seems to have little effect on microhardness distribution across the joint.However,the tensile strength and ductility of the joint have close relation to heating time.Prolonging heating time can improve the tensile strength and ductility of the joint,especially the latter.When the heating time increases to 450 s,solid-state joint with good combination of strength and ductility is attained.展开更多
Thermal self-compressing bonding(TSCB) is a new solid-state bonding method pioneered by the authors. With electron beam as the non-melted heat source, previous experimental study performed on titanium alloys has prove...Thermal self-compressing bonding(TSCB) is a new solid-state bonding method pioneered by the authors. With electron beam as the non-melted heat source, previous experimental study performed on titanium alloys has proved the feasibility of TSCB. However, the thermal stress–strain process during bonding, which is of very important significance in revealing the mechanism of TSCB, was not analysed. In this paper, finite element analysis method is adopted to numerically study the thermal elasto-plastic stress–strain cycle of thermal self-compressing bonding. It is found that due to the localized heating, a non-uniform temperature distribution is formed during bonding, with the highest temperature existed on the bond interface. The expansion of high temperature materials adjacent to the bond interface are restrained by surrounding cool materials and rigid restraints, and thus an internal elasto-plastic stress–strain field is developed by itself which makes the bond interface subjected to thermal compressive action. This thermal self-compressing action combined with the high temperature on the bond interface promotes the atom diffusion across the bond interface to produce solid-state joints. Due to the relatively large plastic deformation, rigid restraint TSCB obtains sound joints in relatively short time compared to diffusion bonding.展开更多
Objective:Conversion of normal cells to cancer cells is often accompanied by abnormal synthesis of serum enzymes.Both alkaline phosphatase(ALP)and lactate dehydrogenase(LDH)have been reported to have prognostic value ...Objective:Conversion of normal cells to cancer cells is often accompanied by abnormal synthesis of serum enzymes.Both alkaline phosphatase(ALP)and lactate dehydrogenase(LDH)have been reported to have prognostic value in a variety of malignancies.The aim of this study was to investigate the effect of preoperative serum ALP and LDH levels on the prognosis of patients with periampullary carcinoma who underwent pancreatoduodenectomy(PD).展开更多
Objective Melanoblasts are the cell source of regeneration for pigment restoration.The ability to differentiate into mature melanocytes is the essential feature of melanoblasts in depigmentation diseases.Cold atmosphe...Objective Melanoblasts are the cell source of regeneration for pigment restoration.The ability to differentiate into mature melanocytes is the essential feature of melanoblasts in depigmentation diseases.Cold atmospheric plasma is an ionized gas with near-room temperature and highly reactive species that has been shown to induce stem cell differentiation.The aim of the study was to explore the effect of cold atmospheric plasma on the differentiation of melanoblast progenitor cells.Methods In this study,melanoblasts were exposed to the plasma jet and the cell morphology was observed.The cell cycle and cell proliferation were detected.Furthermore,the cell immunofluorescence and the detection of melanin particle and nitric oxide were carried out to investigate the differentiation of melanoblast progenitor cells.Results Cells that were treated with the plasma had longer and more synaptic structures,and the G1 phase of cell cycle was prolonged in the treated group.More melanin synthesis-related proteins and melanin particles were produced after plasma treatment.Nitric oxide was one of the active components generated by the plasma jet,and the nitric oxide content in the cell culture medium of the treated group increased.Conclusion These results indicate that an increase in nitric oxide production caused by a plasma jet can promote cell differentiation.The application of plasma provides an innovative strategy for the treatment of depigmentation diseases.展开更多
This study was designed to analyze the effect of the mitochondrial respiratory pathways of Candida albicans （C. albicans） on the biofilm formation. The 2, 3-bis （2-methoxy- 4-nitro-5-sulfophenyl）-2H-tetrazolium-5-...This study was designed to analyze the effect of the mitochondrial respiratory pathways of Candida albicans （C. albicans） on the biofilm formation. The 2, 3-bis （2-methoxy- 4-nitro-5-sulfophenyl）-2H-tetrazolium-5-carboxanilide （XTT） reduction assay was used to measure the metabolic activities of biofilms formed by the C. albicans which were cultured in the presence of respiratory pathways inhibitors. The biofilms formed by the wide type （WT）, GOA1-deleted （GOA31）, GOAl-reconstituted （GOA32）, AOXla-deleted （AOX1） and AOX1b- deleted （AOX2） C. albicans strains were examined by the XTT reduction assay and fluorescence microscopy. The expression of adhesion-related genes BCR1, ALS1, ALS3, ECEI and HWP1 in the biofilms formed by the above five C. albicans strains was detected by real time polymerase chain reaction. It was found that the metabolic activity of biofilms formed by C. albicans was decreased in the presence of alternative oxidase inhibitor whereas it was increased in the presence of classical mitochondrial respiratory pathway complex Ⅲ or complex IV inhibitor. AOX1 strain produced scarce biofilms interspersed with few hyphal filaments. Moreover, no significant changes in the expression of BCR1 and ALS3 were observed in the AOX 1 strain, but the expression of ALS1 and ECE1 was down-regulated, and that of HWP1 was up-regulated. These results indicate that both AOX1 and AOX2 can promote the biofilm formation. However, AOX1a primarily plays a regulatory role in biofilm formation in the absence of inducers where the promoting effect is mainly achieved by promoting mycelial formation.展开更多
To the Editor:Vitiligo is an acquired chronic depigrnentation disorder of the skin resulting from selective destruction of melanocytes.Although it is not a life-threatening disease,it may lead to disfigurement and is ...To the Editor:Vitiligo is an acquired chronic depigrnentation disorder of the skin resulting from selective destruction of melanocytes.Although it is not a life-threatening disease,it may lead to disfigurement and is associated with many other autoimmune diseases.According to a recent international consensus conference,vitiIigo can be cIassified into two major forms: nonsegmental vitiligo (NSV)and segmental vitiligo (SV,accounts for 5-16% of all vitiligo cases).NSV typically evolves over time, in both distribution and extension patterns,including acrofacial, generalized,mucosal,and facial vitiligo [Figure 1a and 1b].SV is relatively rare and is characterized by unilateral or banded distribution along the ganglion segment.SV usually has an early onset and spreads rapidly in the affected dermatomal area,including single SV,double SV,and the multi-SV [Figure 1c and 1d].展开更多
To the Editor： Neurofibromatosis type 1 （NF1） is a common autosomal dominant genetic neurocutaneous disorder mainly characterized by cafe-au-lait macules （CALMs）, neurofibromas,
Oversea hydrocarbon exploration always faces some problems,such as multiple basin types,different exploration prospects,various exploration degrees,diverse data quantities and geological recognitions.This paper focuse...Oversea hydrocarbon exploration always faces some problems,such as multiple basin types,different exploration prospects,various exploration degrees,diverse data quantities and geological recognitions.This paper focuses on overseas basins with different exploration degrees and offers a new evaluation system and research method for fast evaluation and risk analysis on hydrocarbon potential.Based on the theory of probability,this new evaluation system evaluates each parameter and core accumulation factor with comprehensive and quantitative assignment,to accelerate geological evaluation.In addition,this paper suggests that source rock evaluation should be the core criterion in screening evaluation of poorexplored basins,and also proposes that both the exploration potential and geological recognition should drive the evaluation for basins with high exploration degrees.This new system and method,which is an effective system for fast basin evaluation,is suggested to be used in oversea evaluation and decision-making objectively,scientifically and efficiently.展开更多
基金financial support provided by Beijing Aeronautical Manufacturing Technology Research Institutethe help provided by Science and Technology, China, on Power Beam Processes Laboratory at Beijing Aeronautical Manufacturing Technology Research Institute, China
文摘Solid-state bonding between pure titanium and Ti6Al4V(TC4)alloy was conducted by a new bonding method named as rigid restraint thermal self-compressing bonding.Effects of heating time on bonding interface,atom diffusion and mechanical properties of the joints were studied.Results show that atom diffusion between pure titanium and TC4 alloy significantly takes place during bonding.The diffusion depths of Al and V in pure titanium side are increased with increasing heating time.Due to the enhancement of atom diffusion,bond quality of the bonding interface is improved along with the increase of heating time.The heating time seems to have little effect on microhardness distribution across the joint.However,the tensile strength and ductility of the joint have close relation to heating time.Prolonging heating time can improve the tensile strength and ductility of the joint,especially the latter.When the heating time increases to 450 s,solid-state joint with good combination of strength and ductility is attained.
基金Supported by National Natural Science Foundation of China(Grant No.51705491)
文摘Thermal self-compressing bonding(TSCB) is a new solid-state bonding method pioneered by the authors. With electron beam as the non-melted heat source, previous experimental study performed on titanium alloys has proved the feasibility of TSCB. However, the thermal stress–strain process during bonding, which is of very important significance in revealing the mechanism of TSCB, was not analysed. In this paper, finite element analysis method is adopted to numerically study the thermal elasto-plastic stress–strain cycle of thermal self-compressing bonding. It is found that due to the localized heating, a non-uniform temperature distribution is formed during bonding, with the highest temperature existed on the bond interface. The expansion of high temperature materials adjacent to the bond interface are restrained by surrounding cool materials and rigid restraints, and thus an internal elasto-plastic stress–strain field is developed by itself which makes the bond interface subjected to thermal compressive action. This thermal self-compressing action combined with the high temperature on the bond interface promotes the atom diffusion across the bond interface to produce solid-state joints. Due to the relatively large plastic deformation, rigid restraint TSCB obtains sound joints in relatively short time compared to diffusion bonding.
基金This study was supported by the National Natural Science Foundation of China(No.81772950).
文摘Objective:Conversion of normal cells to cancer cells is often accompanied by abnormal synthesis of serum enzymes.Both alkaline phosphatase(ALP)and lactate dehydrogenase(LDH)have been reported to have prognostic value in a variety of malignancies.The aim of this study was to investigate the effect of preoperative serum ALP and LDH levels on the prognosis of patients with periampullary carcinoma who underwent pancreatoduodenectomy(PD).
文摘Objective Melanoblasts are the cell source of regeneration for pigment restoration.The ability to differentiate into mature melanocytes is the essential feature of melanoblasts in depigmentation diseases.Cold atmospheric plasma is an ionized gas with near-room temperature and highly reactive species that has been shown to induce stem cell differentiation.The aim of the study was to explore the effect of cold atmospheric plasma on the differentiation of melanoblast progenitor cells.Methods In this study,melanoblasts were exposed to the plasma jet and the cell morphology was observed.The cell cycle and cell proliferation were detected.Furthermore,the cell immunofluorescence and the detection of melanin particle and nitric oxide were carried out to investigate the differentiation of melanoblast progenitor cells.Results Cells that were treated with the plasma had longer and more synaptic structures,and the G1 phase of cell cycle was prolonged in the treated group.More melanin synthesis-related proteins and melanin particles were produced after plasma treatment.Nitric oxide was one of the active components generated by the plasma jet,and the nitric oxide content in the cell culture medium of the treated group increased.Conclusion These results indicate that an increase in nitric oxide production caused by a plasma jet can promote cell differentiation.The application of plasma provides an innovative strategy for the treatment of depigmentation diseases.
基金This study was supported by the National Natural Science Foundation of China （No. 81371785）.
文摘This study was designed to analyze the effect of the mitochondrial respiratory pathways of Candida albicans （C. albicans） on the biofilm formation. The 2, 3-bis （2-methoxy- 4-nitro-5-sulfophenyl）-2H-tetrazolium-5-carboxanilide （XTT） reduction assay was used to measure the metabolic activities of biofilms formed by the C. albicans which were cultured in the presence of respiratory pathways inhibitors. The biofilms formed by the wide type （WT）, GOA1-deleted （GOA31）, GOAl-reconstituted （GOA32）, AOXla-deleted （AOX1） and AOX1b- deleted （AOX2） C. albicans strains were examined by the XTT reduction assay and fluorescence microscopy. The expression of adhesion-related genes BCR1, ALS1, ALS3, ECEI and HWP1 in the biofilms formed by the above five C. albicans strains was detected by real time polymerase chain reaction. It was found that the metabolic activity of biofilms formed by C. albicans was decreased in the presence of alternative oxidase inhibitor whereas it was increased in the presence of classical mitochondrial respiratory pathway complex Ⅲ or complex IV inhibitor. AOX1 strain produced scarce biofilms interspersed with few hyphal filaments. Moreover, no significant changes in the expression of BCR1 and ALS3 were observed in the AOX 1 strain, but the expression of ALS1 and ECE1 was down-regulated, and that of HWP1 was up-regulated. These results indicate that both AOX1 and AOX2 can promote the biofilm formation. However, AOX1a primarily plays a regulatory role in biofilm formation in the absence of inducers where the promoting effect is mainly achieved by promoting mycelial formation.
基金a grant from the National Natural Science Foundation of China (No.81773306).
文摘To the Editor:Vitiligo is an acquired chronic depigrnentation disorder of the skin resulting from selective destruction of melanocytes.Although it is not a life-threatening disease,it may lead to disfigurement and is associated with many other autoimmune diseases.According to a recent international consensus conference,vitiIigo can be cIassified into two major forms: nonsegmental vitiligo (NSV)and segmental vitiligo (SV,accounts for 5-16% of all vitiligo cases).NSV typically evolves over time, in both distribution and extension patterns,including acrofacial, generalized,mucosal,and facial vitiligo [Figure 1a and 1b].SV is relatively rare and is characterized by unilateral or banded distribution along the ganglion segment.SV usually has an early onset and spreads rapidly in the affected dermatomal area,including single SV,double SV,and the multi-SV [Figure 1c and 1d].
基金This study was supported by a grant from the National Natural Science Foundation of China （No. 81371728）.
文摘To the Editor： Neurofibromatosis type 1 （NF1） is a common autosomal dominant genetic neurocutaneous disorder mainly characterized by cafe-au-lait macules （CALMs）, neurofibromas,
文摘Oversea hydrocarbon exploration always faces some problems,such as multiple basin types,different exploration prospects,various exploration degrees,diverse data quantities and geological recognitions.This paper focuses on overseas basins with different exploration degrees and offers a new evaluation system and research method for fast evaluation and risk analysis on hydrocarbon potential.Based on the theory of probability,this new evaluation system evaluates each parameter and core accumulation factor with comprehensive and quantitative assignment,to accelerate geological evaluation.In addition,this paper suggests that source rock evaluation should be the core criterion in screening evaluation of poorexplored basins,and also proposes that both the exploration potential and geological recognition should drive the evaluation for basins with high exploration degrees.This new system and method,which is an effective system for fast basin evaluation,is suggested to be used in oversea evaluation and decision-making objectively,scientifically and efficiently.
