Objective:In many countries,the cervical cancer prevalence has declined but less information about the changes is available in China.This study aims to understand the epidemiological characteristics and trend of cerv...Objective:In many countries,the cervical cancer prevalence has declined but less information about the changes is available in China.This study aims to understand the epidemiological characteristics and trend of cervical cancer in China.Methods:Cervical cancer data of 11 cancer registries during 1988-2002 in China were analyzed.The age and urban/rural differences and trend of cervical cancer incidence and mortality were described and discussed.Results:During 1988-2002,a total of 6007 incidence cases and 3749 mortality cases of cervical cancer were reported in the 11 cancer registries.The incidence crude rate of cervical cancer was 3.80/100,000 and the world age adjusted rate was 2.78/100,000.In the same period,the mortality crude rate was 2.37/100,000 and the world age adjusted rate was 1.66/100,000.Declined incidence and mortality trends were observed during this period in urban as well as in rural areas.When calculating the rates by age group,we found that the declining trends were only for older women and increasing trends for younger women,especially for women in the rural areas.Conclusion:The incidence and mortality rates declined during the period of 1988-2002 in China for older women.The younger women showed an increasing trend during the same period,especially for women in rural area.展开更多
AIM:To clarify the association between Helicobacter pylori(H.pylori)infection and the risk of esophageal carcinoma through a meta-analysis of published data.METHODS:Studies which reported the association between H.pyl...AIM:To clarify the association between Helicobacter pylori(H.pylori)infection and the risk of esophageal carcinoma through a meta-analysis of published data.METHODS:Studies which reported the association between H.pylori infection and esophageal cancer published up to June 2013 were included.The odds ratios(ORs)and corresponding 95%CIs of H.pyloriinfection on esophageal cancer with respect to health control groups were evaluated.Data were extracted independently by two investigators and discrepancies were resolved by discussion with a third investigator.The statistical software,STATA(version 12.0),was applied to investigate heterogeneity among individual studies and to summarize the studies.A meta-analysis was performed using a fixed-effect or random-effect method,depending on the absence or presence of significant heterogeneity.RESULTS:No significant association between H.pylori infection and esophageal squamous cell carcinoma(ESCC)risk was found in the pooled overall population(OR=0.97,95%CI:0.76-1.24).However,significant associations between H.pylori infection and ESCC risk were found in Eastern subjects(OR=0.66,95%CI:0.43-0.89).Similarly,cytotoxin-associated gene-A(CagA)positive strains of infection may decrease the risk of ESCC in Eastern subjects(OR=0.77,95%CI:0.65-0.92),however,these associations were not statistically significant in Western subjects(OR=1.26,95%CI:0.97-1.63).For esophageal adenocarcinoma(EAC)the summary OR for H.pylori infection and CagA positive strains of infection were 0.59(95%CI:0.51-0.68)and 0.56(95%CI:0.45-0.70),respectively.CONCLUSION:H.pylori infection is associated with a decreased risk of ESCC in Eastern populations and a decreased risk of EAC in the overall population.展开更多
Brain metastasis from esophageal carcinoma(BMEC) is very rare, but its incidence has increased in the United States, Japan, China and other counties. Reports on BMEC have largely been focused on examining whether adju...Brain metastasis from esophageal carcinoma(BMEC) is very rare, but its incidence has increased in the United States, Japan, China and other counties. Reports on BMEC have largely been focused on examining whether adjuvant therapy for esophageal cancer influences the survival duration of BMEC patients and on the imaging characteristics of BMEC determined using new medical equipment. The difference between different pathological types of esophageal cancer, especially adenocarcinoma and squamous cell carcinoma, is one important factor used to assess the influence of BMEC. Adjuvant therapy, including radiotherapy and chemotherapy, for esophageal cancer with different characteristics in different countries may affect BMEC treatment outcomes. The degree of popularization of advanced medical equipment is a major concern related to the prevalence of BMEC. Furthermore,targeted BMEC treatment is under development in developed countries. In this article, we reviewed the debate surrounding BMEC and analyzed BMEC studies from different perspectives.展开更多
The rheo-diecasting mold filling capacity and the microstructure of the semi-solid A380 aluminum alloy slurry were investigated. The results show that the mold filling capacity was strengthened with increasing pouring...The rheo-diecasting mold filling capacity and the microstructure of the semi-solid A380 aluminum alloy slurry were investigated. The results show that the mold filling capacity was strengthened with increasing pouring temperature or increasing injection pressure. Under certain process parameters, the mold cavity was fully filled. However, the mold filling capacity decreased with increasing holding time. The mold filling capacity was improved with increasing shape factor of primary α(Al) grains; however, the solid fraction and the grain size significantly increased at the same time. In addition, the microstructures along the route of the spiral samples obviously differed. The grain size decreased gradually from the near-end to the far-end, whereas the shape factor increased gradually.展开更多
The effects of pouring temperature,vibration frequency,and the number of curves in a serpentine channel,on themicrostructure and mechanical properties of Al-30%Si alloy processed by rheo-diecasting(RDC)were investigat...The effects of pouring temperature,vibration frequency,and the number of curves in a serpentine channel,on themicrostructure and mechanical properties of Al-30%Si alloy processed by rheo-diecasting(RDC)were investigated.The semisolidAl-30%Si alloy slurry was prepared by vibration serpentine channel pouring(VSCP)process in the RDC process.The results showthat the pouring temperature,the vibration frequency,and the number of the curves strongly affect the microstructure and mechanicalproperties of Al-30%Si alloy.Under experimental conditions of a pouring temperature of850°C,a twelve-curve copper channel anda vibration frequency of80Hz,the primary Si grains are refined into fine compact grains with average grain size of about24.6μm inthe RDC samples assisted with VSCP.Moreover,the ultimate tensile strength(UTS),elongation and hardness of the RDC sample are296MPa,0.87%and HB155,respectively.It is concluded that the VSCP process can effectively refine the primary Si grains.Therefinement of primary Si grains is the major cause for the improvement of the mechanical properties of the RDC sample.展开更多
A water-cooled serpentine channel pouring process was invented to produce semi-solid A356 aluminum alloy slurry for rheocast ing, and the effects of pouring temperature and circulating cooling water flux on the micros...A water-cooled serpentine channel pouring process was invented to produce semi-solid A356 aluminum alloy slurry for rheocast ing, and the effects of pouring temperature and circulating cooling water flux on the microstmcture of the slurry were investigated. The results show that at the pouring temperature of 640-680~C and the circulating cooling water flux of 0.9 m3/h, the semi-solid A356 aluminum alloy slurry with spherical primary a(A1) grains can be obtained, whose shape factors are between 0.78 and 0.86 and the grain diameter can reach 48-68 ~am. When the pouring temperatures are at 660-680~C, only a very thin solidified shell remains inside the serpentine channel and can be removed easily. When the serpentine channel is cooled with circulating water, the microstructure of the semi-solid slurry can be improved, and the serpentine channel is quickly cooled to room temperature after the completion of one pouring. In terms of the productivity of the special equipment, the water-cooled serpentine channel is economical and efficient.展开更多
Fine spheroidal and equiaxed nondendritic microstructures required for semisolid casting can be formed through a serpentine pouting channel. Effects of the pouring temperature and the vertical section length of the se...Fine spheroidal and equiaxed nondendritic microstructures required for semisolid casting can be formed through a serpentine pouting channel. Effects of the pouring temperature and the vertical section length of the serpentine pouring channel were studied. The results indicate that both favorable semisolid microstructures of A356 aluminum alloy can be generated by a serpentine pouring channel, and the solid shell inside the channel can be avoided when the pouting temperature is in the range from 660 to 680℃. It is also shown that the vertical section length of the serpentine pouting channel has a significant influence on the microstructure of the feedstock, namely both the microstructure of the feedstock and the microstructure uniformity in the radial direction get worse when the vertical section length is shortened; moreover, the pouring temperature for obtaining the feedstock with suitable microstructure decreases. The relevant mechanisms were discussed.展开更多
A semisolid slurry of 7075 aluminum alloy was prepared by means of a serpentine channel process(SCP) and rheo-diecasting. The influences of pouring temperature during slurry preparation,the injection pressure and die ...A semisolid slurry of 7075 aluminum alloy was prepared by means of a serpentine channel process(SCP) and rheo-diecasting. The influences of pouring temperature during slurry preparation,the injection pressure and die preheat temperature on the mechanical properties and microstructure of a rheo-diecast 7075 aluminum alloy were investigated. The results show that the as-cast strength and elongation of the tensile samples were 210-260 MPa and 0.2%-1.7%,respectively,with an injection pressure of 130 MPa,a pouring temperature of 700-720 oC,a preheat temperature of 280-350 oC,and a plunger speed of 0.5 m·s-1. The results also show that the aged strength and elongation of the tensile samples were 420-453 MPa and 1.0%-1.4%,respectively,when the alloy solution was treated at 470 oC for 12 h and aged at 120 oC for 24 h. The substantial shrinkage porosity in the 7075 aluminum alloy tensile samples was the main cause of low elongation.展开更多
The cooling control of the melt during the casting process is of great significance. A comprehensive closed-loop cooling control of castings by adopting a skeletal sand mold design was proposed. The skeletal sand mold...The cooling control of the melt during the casting process is of great significance. A comprehensive closed-loop cooling control of castings by adopting a skeletal sand mold design was proposed. The skeletal sand mold consisting of an adaptive shell, functional cavities and a support was designed and created based on the finite difference meshes of a casting. It was applied to a round wall test casting. Two kinds of skeletal sand molds, one with lattice support and the other with enforcing ribs for this casting were designed and printed out by the 3 D printing(3 DP) method. Aluminum alloy A356 was cast by using these two sand molds. The first mold was cooled by natural convection, the other one by water spray cooling. Two sound castings were obtained. The sand mold temperature, cooling curves, microstructures, mechanical properties, residual stress and deformation were measured, compared and discussed. Water spray cooling hastened the cooling rate by 62%, increased the content of Mg and Cu in the α-Al matrix, improved the mechanical properties, and altered the surface residual stress state.展开更多
The semi-solid 6061 aluminum alloy slurry was prepared by a serpentine channel pouring process. The effects of pouring temperature, bend number and bend diameter on the microstructures were investigated. Microstructur...The semi-solid 6061 aluminum alloy slurry was prepared by a serpentine channel pouring process. The effects of pouring temperature, bend number and bend diameter on the microstructures were investigated. Microstructural evolution mechanism of the semi-solid slurry during the pouring process was also analyzed. The results show that the grain is refined and the grain roundness is improved by controlling the pouring temperature close to the liquidus temperature, and the nucleation rate of primary α(Al) grains is effectively increased via increasing the bend number and decreasing the bend diameter. The primary grains are not only formed directly from the alloy melt via chilling nucleation and heterogeneous nucleation, but also evolved from the fractured dendrite fragments. Meanwhile, the heat exchange between the melt and the serpentine channel is increased by the “self-stirring” effect in the melt, which also promotes the refinement and spheroidization of primary α(Al) grains.展开更多
In this paper, the microstructure evolution of the rapidly solidified (RS) Mg61.7Zn34Gd4.3 (at%, atomic ratio) alloy at high temperatures was investigated. The hardness and elastic modulus of the main precipitated pha...In this paper, the microstructure evolution of the rapidly solidified (RS) Mg61.7Zn34Gd4.3 (at%, atomic ratio) alloy at high temperatures was investigated. The hardness and elastic modulus of the main precipitated phases were also analyzed and compared with those of the α-Mg matrix on the basis of nanoindentation tests. The results show that the RS alloy consists of either a petal-like icosahedral quasicrystal (IQC) phase (~20 μm) and block-shaped H1 phase (~15 μm) or IQC particles with an average grain size of ~107 nm as well as a small proportion of amorphous phase, which mainly depends on the holding time at the liquid temperature and the thickness of the ribbons. The IQC phase gradually transforms at 400?C to a short-rod-shaped μ-phase (Mg28.6Zn63.8Gd7.7) with a hexagonal structure. The hardness of the IQC phase is higher than that of H1 phase, and both phases exhibit a higher hardness than the α-Mg matrix and the μ-phase. The elasticity of the H1 phase is superior to that of the α-Mg matrix. The IQC phase possesses a higher elastic modulus than H1 phase. The easily formed H1 phase exhibits the poorest plastic deformation capacity among these phases but a higher elastic modulus than the α-Mg matrix.展开更多
The effect of injection pressure, piston velocity, and the forming temperature of semisolid slurry on the filling behavior of the semi-solid A356 aluminum alloy was investigated by simulation methods. The simulation r...The effect of injection pressure, piston velocity, and the forming temperature of semisolid slurry on the filling behavior of the semi-solid A356 aluminum alloy was investigated by simulation methods. The simulation results show that these processing parameters have an important effect on the filling behavior of the semi-solid A356 aluminum alloy. The slurry flows steadily in the cavity when the injection pressure, the piston velocity, and the forming temperature are low, but it is prone to turbulent flow when the injection pressure, the piston velocity, and the forming temperature are much higher. Therefore it is necessary to determine the appropriate processing parameters to get a steady flow of the slurry in the cavity.展开更多
In this study, a serpentine channel pouring process was used to prepare the semi-solid A1-20%Si alloy slurry and refine primary Si grains in the alloy. The effects of the pouring temperature, number of curves in the s...In this study, a serpentine channel pouring process was used to prepare the semi-solid A1-20%Si alloy slurry and refine primary Si grains in the alloy. The effects of the pouring temperature, number of curves in the serpentine channel, and material of the serpentine channel on the size of primary Si grains in the semi-solid A1-20%Si alloy slurry were investigated. The results showed that the pouting temperature, number of the curves, and material of the channel strongly affected the size and distribution of the primary Si grains. The pouring tempera- ture exerted the strongest effect, followed by the number of the curves and then the material of the channel. Under experimental conditions of a four-curve copper channel and a pouring temperature of 701℃, primary Si grains in the semi-solid A1-20%Si alloy slurry were refined to the greatest extent, and the lath-like grains were changed into granular grains. Moreover, the equivalent grain diameter and the average shape coefficient of primary Si grains in the satisfactory semi-solid A1-20%Si alloy slurry were 24.4 μm and 0.89, respectively. Finally, the re- finement mechanism and distribution rule of primary Si grains in the slurry prepared through the serpentine channel pouring process were analyzed and discussed.展开更多
In this paper, the serpentine channel pouring process for preparing a semi-solid A390 alloy slurry and refining the primary Si grains of the A390 alloy, was used. The effects of the pouring temperature, the cooling wa...In this paper, the serpentine channel pouring process for preparing a semi-solid A390 alloy slurry and refining the primary Si grains of the A390 alloy, was used. The effects of the pouring temperature, the cooling water flow and the number of the curves on the size of the primary Si grains in the semi-solid A390 alloy slurry were investigated. The results show that the pouring temperature, the cooling water flow and the number of the curves have a major effect on the size and the distribution of primary Si grains. Under the experimental condition of the four-curve copper channel whose cooling water flow was 500 L·h-1 and the pouring temperature was 690 oC, the primary Si grains of the semi-solid A390 alloy slurry were refined to the greatest extent and the lath-like grains were changed into granular ones. Additionally, the equivalent grain diameter and the average shape factor of the primary Si grains of the satisfactory semi-solid A390 alloy slurry are 18.6 μm and 0.8, respectively. Further, the refinement mechanism of the primary Si grains through the serpentine channel pouring process was analyzed and discussed. In summary, the primary Si nuclei could be easily precipitated due to the chilling effect of the channel inner wall, thus the primary Si grains were greatly refined. Meanwhile, the subsequent alloy melt fluid also promoted the separation of primary Si grains from the inner wall, further refining the primary Si grains.展开更多
The semisolid slurry of Al-Zn-Mg-Cu alloy was prepared through a self-designed water-cooled copper serpentine pouring channel(WSPC) machine. Influences of pouring temperature, the number of turns and the cooling water...The semisolid slurry of Al-Zn-Mg-Cu alloy was prepared through a self-designed water-cooled copper serpentine pouring channel(WSPC) machine. Influences of pouring temperature, the number of turns and the cooling water flow rate on the microstructure of the semisolid Al-Zn-Mg-Cu alloy slurry were investigated. The results show that the semisolid Al-Zn-Mg-Cu alloy slurry with satisfactory quality can be generated by the WSPC when the pouring temperature is in the range between 680 ℃ and 700 ℃. At a given pouring temperature, the average grain size of primary α-Al decreases and the shape factor increases with the increase of the number of turns. When the cooling water flow rate is 450 L·h^(-1), the obtained semisolid slurry is optimal. During the preparation of the semisolid Al-Zn-Mg-Cu alloy slurry with low superheat pouring, the alloy melt has mixed inhibition and convection flow characteristics by "self-stirring". When the alloy melt flows through the serpentine channel, the chilling effect of the inner wall of the channel, the convection and mixed inhibition of the alloy melt greatly promote the heterogeneous nucleation and grain segregation. This effect destroys the dendrite growth mode under traditional solidification conditions, and the primary nuclei gradually evolve into spherical or nearspherical grains.展开更多
An apparent viscosity model of semi-solid A356 aluminum alloy has been developed and the software Castsofl6.0 coupled with the model has been used to simulate the mould filling of an automobile master brake cylinder w...An apparent viscosity model of semi-solid A356 aluminum alloy has been developed and the software Castsofl6.0 coupled with the model has been used to simulate the mould filling of an automobile master brake cylinder with the semi-solid A356 aluminum alloy slurry. The simulation results are in agreement with the practical filling process, indicating that the apparent viscosity model is feasible and can be used to simulate the mould filling of the semisolid A356 aluminum alloy slurry and can be used to optimize the filling process and the design of dies. A higher injection pressure, a higher ingate flow velocity of the semi-solid slurry, and a higher slurry temperature are advantageous to the mould filling of the automobile master brake cylinder.展开更多
In this paper, the effects of rheo-diecast process parameters and T6 heat treatment on the microstructure and mechanical properties of the rheo-diecasting(RDC) semi-solid A390 alloy prepared through pure copper serp...In this paper, the effects of rheo-diecast process parameters and T6 heat treatment on the microstructure and mechanical properties of the rheo-diecasting(RDC) semi-solid A390 alloy prepared through pure copper serpentine channel were investigated. The results indicate that the mechanical properties of the RDC samples change with the pouring temperature and injection pressure. In this case, a lower pouring temperature results in better tensile strength and elongation of the RDC A390 alloy; however, the tensile strength and elongation decrease when the pouring temperature decreases to 660°C. Higher injection pressures result in the improved mechanical properties of the RDC A390 alloy. To some extent, T6 heat treatment improves the tensile strength and ductility of the RDC A390 alloy compared to those of the non-heat treated alloy. However, when the pouring temperature and injection pressure are greater than 670°C and 70 MPa, respectively, the mechanical properties are sharply diminished.展开更多
EMERGING-CTONG 1103 showed improved progression-free survival(PFS)with neoadjuvant erlotinib vs.chemotherapy for patients harbouring EGFR sensibility mutations and R0 resected stage IIIA-N2 non-small cell lung cancer(...EMERGING-CTONG 1103 showed improved progression-free survival(PFS)with neoadjuvant erlotinib vs.chemotherapy for patients harbouring EGFR sensibility mutations and R0 resected stage IIIA-N2 non-small cell lung cancer(NSCLC)(NCT01407822).Herein,we report the final results.Recruited patients were randomly allocated 1:1 to the erlotinib group(150 mg/day orally;neoadjuvant phase for 42 days and adjuvant phase to 12 months)or to the GC group(gemcitabine 1250 mg/m2 plus cisplatin 75 mg/m2 intravenously;2 cycles in neoadjuvant phase and 2 cycles in adjuvant phase).Objective response rate(ORR),complete pathologic response(pCR),PFS,and overall survival(OS)were assessed along with safety.Post hoc analysis was performed for subsequent treatments after disease recurrence.Among investigated 72 patients(erlotinib,n=37;GC,n=35),the median follow-up was 62.5 months.The median OS was 42.2 months(erlotinib)and 36.9 months(GC)(hazard ratio[HR],0.83;95%confidence interval[CI],0.47-1.47;p=0.513).The 3-and_(5-y)ear OS rates were 58.6%and 40.8%with erlotinib and 55.9%and 27.6%with GC(p_(3-y)=0.819,p_(5-y)=0.252).Subsequent treatment was administered in 71.9%and 81.8%of patients receiving erlotinib and GC,respectively;targeted therapy contributed mostly to OS(HR,0.35;95%CI,0.18-0.70).After disease progression,the ORR was 53.3%,and the median PFS was 10.9 months during the EGFR-TKI rechallenge.During postoperative therapy,grade 3 or 4 adverse events(AEs)were 13.5%in the erlotinib group and 29.4%in the GC group.No serious adverse events were observed.Erlotinib exhibited clinical feasibility for resectable IIIA-N2 NSCLC over chemotherapy in the neoadjuvant setting.展开更多
Low-temperature slab-reheated grain-oriented silicon steel is characterized by a sharp {411}〈148〉 primary recrystallization texture. To date, the influence of this texture on secondary recrystallization is not clear...Low-temperature slab-reheated grain-oriented silicon steel is characterized by a sharp {411}〈148〉 primary recrystallization texture. To date, the influence of this texture on secondary recrystallization is not clear. Microtextures in primary and secondary reerystallized sheets of low-temperature reheated grain-oriented silicon steel were examined using electron backscatter diffraction. By comparing the textures and microstructures of specific primary reerystallized grains neighboring secondary grains with those of other primary grains, the influences of primary re- crystallization textures and microstructures on the orientations of secondary grains were investigated. Results show that for low-temperature reheated graiworiented silicon steel, the primary recrystallization sheet comprises { 411 } 〈148〉, {111}〈112〉, and {001}〈120〉 texture componems. During secondary recrystallization, the {111}〈112〉 primary recrystallized grains were easily consumed by abnormally grown Goss, deviated Goss, Brass, or {210}〈001〉grains ;the { 411 }〈148〉 primary recrystallized grains were more resistant to being swallowed; and the {001} 〈120 grains were the most resistant to being consumed. For a particular primary grain, the distribution of its surrounding grain boundaries determined how easily it is consumed during secondary recrystallization. Primary grains surrounded by 20°- 45° grain boundaries were consumed much earlier than those having grain boundaries above 45°, which is in accordance with high-energy grain boundary theory. In addition, special ∑9 boundaries between {411}〈148〉 and Goss grains move more slowly than ∑9 boundaries between {111 }〈112〉 and Goss grains, which is attributed to the different positions of 〈110〉 rotation axis with respect to the normals of grain boundaries.展开更多
In this study, high- and low-grade grain-oriented electrical steels were used as the initial materials to produce 0.08-mm-thick sheet with one-step cold-rolling method. Electron backscattering diffraction analysis tec...In this study, high- and low-grade grain-oriented electrical steels were used as the initial materials to produce 0.08-mm-thick sheet with one-step cold-rolling method. Electron backscattering diffraction analysis technique and X-ray diffraction texture analysis technique were adopted to investigate the effect of initial Goss texture sharpness on texture evolution and magnetic properties of ultra-thin grain-oriented electrical steel. The results showed that primary recrystal- lization and secondary recrystallization were the main processes that occurred during annealing. The induced factors for secondary recrystallization of two grades samples were not Consistent. The high-grade samples presented texture induction mechanism, while the low-grade samples revealed strong surface-energy induction mechanism. The initial Goss texture sharpness had a great impact on texture evolution and magnetic properties of ultra-thin grain-oriented electrical steel. The Goss texture component formed after primary recrystallization was stronger, and better magnetic properties were obtained at low frequencies. For low-grade samples, secondary recrystallization enhanced the intensity of Goss texture, and both grain size and texture contributed to better high-frequency magnetic properties after secondary recrystallization. By controlling the annealing process, the magnetic properties of low-grade products could be significantly improved, thus achieving conversion from low-grade to high-grade products.展开更多
基金supported by the Eleventh Five Years Grant from the Ministry of Civil Affairs of China (No. 2008-47-2-10)
文摘Objective:In many countries,the cervical cancer prevalence has declined but less information about the changes is available in China.This study aims to understand the epidemiological characteristics and trend of cervical cancer in China.Methods:Cervical cancer data of 11 cancer registries during 1988-2002 in China were analyzed.The age and urban/rural differences and trend of cervical cancer incidence and mortality were described and discussed.Results:During 1988-2002,a total of 6007 incidence cases and 3749 mortality cases of cervical cancer were reported in the 11 cancer registries.The incidence crude rate of cervical cancer was 3.80/100,000 and the world age adjusted rate was 2.78/100,000.In the same period,the mortality crude rate was 2.37/100,000 and the world age adjusted rate was 1.66/100,000.Declined incidence and mortality trends were observed during this period in urban as well as in rural areas.When calculating the rates by age group,we found that the declining trends were only for older women and increasing trends for younger women,especially for women in the rural areas.Conclusion:The incidence and mortality rates declined during the period of 1988-2002 in China for older women.The younger women showed an increasing trend during the same period,especially for women in rural area.
基金Supported by China Postdoctoral Science Foundation,No.2012M521189Zhejiang Provincial Postdoctoral Science Foundation,No.Bsh1202064+2 种基金National Natural Science Foundation ofChina,No.81172081Zhejiang Provincial Natural Science Foundation,No.LY13H160024Wu Jieping Medical Foundation,No.2011,3206750.11059 and 11091
文摘AIM:To clarify the association between Helicobacter pylori(H.pylori)infection and the risk of esophageal carcinoma through a meta-analysis of published data.METHODS:Studies which reported the association between H.pylori infection and esophageal cancer published up to June 2013 were included.The odds ratios(ORs)and corresponding 95%CIs of H.pyloriinfection on esophageal cancer with respect to health control groups were evaluated.Data were extracted independently by two investigators and discrepancies were resolved by discussion with a third investigator.The statistical software,STATA(version 12.0),was applied to investigate heterogeneity among individual studies and to summarize the studies.A meta-analysis was performed using a fixed-effect or random-effect method,depending on the absence or presence of significant heterogeneity.RESULTS:No significant association between H.pylori infection and esophageal squamous cell carcinoma(ESCC)risk was found in the pooled overall population(OR=0.97,95%CI:0.76-1.24).However,significant associations between H.pylori infection and ESCC risk were found in Eastern subjects(OR=0.66,95%CI:0.43-0.89).Similarly,cytotoxin-associated gene-A(CagA)positive strains of infection may decrease the risk of ESCC in Eastern subjects(OR=0.77,95%CI:0.65-0.92),however,these associations were not statistically significant in Western subjects(OR=1.26,95%CI:0.97-1.63).For esophageal adenocarcinoma(EAC)the summary OR for H.pylori infection and CagA positive strains of infection were 0.59(95%CI:0.51-0.68)and 0.56(95%CI:0.45-0.70),respectively.CONCLUSION:H.pylori infection is associated with a decreased risk of ESCC in Eastern populations and a decreased risk of EAC in the overall population.
基金Supported by Zhejiang Province Science and Technology Project of Traditional Chinese Medicine,No.2011ZB017the Talent Project of Medical and Health Sciences Fund of Zhejiang Province,No.2012RCB005
文摘Brain metastasis from esophageal carcinoma(BMEC) is very rare, but its incidence has increased in the United States, Japan, China and other counties. Reports on BMEC have largely been focused on examining whether adjuvant therapy for esophageal cancer influences the survival duration of BMEC patients and on the imaging characteristics of BMEC determined using new medical equipment. The difference between different pathological types of esophageal cancer, especially adenocarcinoma and squamous cell carcinoma, is one important factor used to assess the influence of BMEC. Adjuvant therapy, including radiotherapy and chemotherapy, for esophageal cancer with different characteristics in different countries may affect BMEC treatment outcomes. The degree of popularization of advanced medical equipment is a major concern related to the prevalence of BMEC. Furthermore,targeted BMEC treatment is under development in developed countries. In this article, we reviewed the debate surrounding BMEC and analyzed BMEC studies from different perspectives.
基金financially supported by the National Basic Research Program of China (No. 2011CB606300)the National Natural Science Foundation of China (No. 5077400)
文摘The rheo-diecasting mold filling capacity and the microstructure of the semi-solid A380 aluminum alloy slurry were investigated. The results show that the mold filling capacity was strengthened with increasing pouring temperature or increasing injection pressure. Under certain process parameters, the mold cavity was fully filled. However, the mold filling capacity decreased with increasing holding time. The mold filling capacity was improved with increasing shape factor of primary α(Al) grains; however, the solid fraction and the grain size significantly increased at the same time. In addition, the microstructures along the route of the spiral samples obviously differed. The grain size decreased gradually from the near-end to the far-end, whereas the shape factor increased gradually.
基金Project(5077400) supported by the National Natural Science Foundation of China
文摘The effects of pouring temperature,vibration frequency,and the number of curves in a serpentine channel,on themicrostructure and mechanical properties of Al-30%Si alloy processed by rheo-diecasting(RDC)were investigated.The semisolidAl-30%Si alloy slurry was prepared by vibration serpentine channel pouring(VSCP)process in the RDC process.The results showthat the pouring temperature,the vibration frequency,and the number of the curves strongly affect the microstructure and mechanicalproperties of Al-30%Si alloy.Under experimental conditions of a pouring temperature of850°C,a twelve-curve copper channel anda vibration frequency of80Hz,the primary Si grains are refined into fine compact grains with average grain size of about24.6μm inthe RDC samples assisted with VSCP.Moreover,the ultimate tensile strength(UTS),elongation and hardness of the RDC sample are296MPa,0.87%and HB155,respectively.It is concluded that the VSCP process can effectively refine the primary Si grains.Therefinement of primary Si grains is the major cause for the improvement of the mechanical properties of the RDC sample.
基金financially supported by the National Natural Science Foundation of China (No.50774007)the National High-Tech Research and Development Program of China (No.2006AA03Z115)the National Basic Research Priorities Program of China(No.2011CB606302-1.)
文摘A water-cooled serpentine channel pouring process was invented to produce semi-solid A356 aluminum alloy slurry for rheocast ing, and the effects of pouring temperature and circulating cooling water flux on the microstmcture of the slurry were investigated. The results show that at the pouring temperature of 640-680~C and the circulating cooling water flux of 0.9 m3/h, the semi-solid A356 aluminum alloy slurry with spherical primary a(A1) grains can be obtained, whose shape factors are between 0.78 and 0.86 and the grain diameter can reach 48-68 ~am. When the pouring temperatures are at 660-680~C, only a very thin solidified shell remains inside the serpentine channel and can be removed easily. When the serpentine channel is cooled with circulating water, the microstructure of the semi-solid slurry can be improved, and the serpentine channel is quickly cooled to room temperature after the completion of one pouring. In terms of the productivity of the special equipment, the water-cooled serpentine channel is economical and efficient.
基金supported by the National Basic Research Program of China (No.2006CB605203)the National High-Tech Research and Development Program of China (No.2006AA03Z115)the National Natural Science Foundation of China (No.50774007)
文摘Fine spheroidal and equiaxed nondendritic microstructures required for semisolid casting can be formed through a serpentine pouting channel. Effects of the pouring temperature and the vertical section length of the serpentine pouring channel were studied. The results indicate that both favorable semisolid microstructures of A356 aluminum alloy can be generated by a serpentine pouring channel, and the solid shell inside the channel can be avoided when the pouting temperature is in the range from 660 to 680℃. It is also shown that the vertical section length of the serpentine pouting channel has a significant influence on the microstructure of the feedstock, namely both the microstructure of the feedstock and the microstructure uniformity in the radial direction get worse when the vertical section length is shortened; moreover, the pouring temperature for obtaining the feedstock with suitable microstructure decreases. The relevant mechanisms were discussed.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.50774007,51771032 and 51701078)China Postdoctoral Science Foundation(Grant No.2018M632846)the Scientific Research Program of Hubei Provincial Education Department(Grant No.B2016053)
文摘A semisolid slurry of 7075 aluminum alloy was prepared by means of a serpentine channel process(SCP) and rheo-diecasting. The influences of pouring temperature during slurry preparation,the injection pressure and die preheat temperature on the mechanical properties and microstructure of a rheo-diecast 7075 aluminum alloy were investigated. The results show that the as-cast strength and elongation of the tensile samples were 210-260 MPa and 0.2%-1.7%,respectively,with an injection pressure of 130 MPa,a pouring temperature of 700-720 oC,a preheat temperature of 280-350 oC,and a plunger speed of 0.5 m·s-1. The results also show that the aged strength and elongation of the tensile samples were 420-453 MPa and 1.0%-1.4%,respectively,when the alloy solution was treated at 470 oC for 12 h and aged at 120 oC for 24 h. The substantial shrinkage porosity in the 7075 aluminum alloy tensile samples was the main cause of low elongation.
基金funded by the National Natural Science Foundation of China (No. 51875308)。
文摘The cooling control of the melt during the casting process is of great significance. A comprehensive closed-loop cooling control of castings by adopting a skeletal sand mold design was proposed. The skeletal sand mold consisting of an adaptive shell, functional cavities and a support was designed and created based on the finite difference meshes of a casting. It was applied to a round wall test casting. Two kinds of skeletal sand molds, one with lattice support and the other with enforcing ribs for this casting were designed and printed out by the 3 D printing(3 DP) method. Aluminum alloy A356 was cast by using these two sand molds. The first mold was cooled by natural convection, the other one by water spray cooling. Two sound castings were obtained. The sand mold temperature, cooling curves, microstructures, mechanical properties, residual stress and deformation were measured, compared and discussed. Water spray cooling hastened the cooling rate by 62%, increased the content of Mg and Cu in the α-Al matrix, improved the mechanical properties, and altered the surface residual stress state.
文摘The semi-solid 6061 aluminum alloy slurry was prepared by a serpentine channel pouring process. The effects of pouring temperature, bend number and bend diameter on the microstructures were investigated. Microstructural evolution mechanism of the semi-solid slurry during the pouring process was also analyzed. The results show that the grain is refined and the grain roundness is improved by controlling the pouring temperature close to the liquidus temperature, and the nucleation rate of primary α(Al) grains is effectively increased via increasing the bend number and decreasing the bend diameter. The primary grains are not only formed directly from the alloy melt via chilling nucleation and heterogeneous nucleation, but also evolved from the fractured dendrite fragments. Meanwhile, the heat exchange between the melt and the serpentine channel is increased by the “self-stirring” effect in the melt, which also promotes the refinement and spheroidization of primary α(Al) grains.
基金supported by the Youth Science Fund Project of National Natural Science Fund of China (No. 51401070)
文摘In this paper, the microstructure evolution of the rapidly solidified (RS) Mg61.7Zn34Gd4.3 (at%, atomic ratio) alloy at high temperatures was investigated. The hardness and elastic modulus of the main precipitated phases were also analyzed and compared with those of the α-Mg matrix on the basis of nanoindentation tests. The results show that the RS alloy consists of either a petal-like icosahedral quasicrystal (IQC) phase (~20 μm) and block-shaped H1 phase (~15 μm) or IQC particles with an average grain size of ~107 nm as well as a small proportion of amorphous phase, which mainly depends on the holding time at the liquid temperature and the thickness of the ribbons. The IQC phase gradually transforms at 400?C to a short-rod-shaped μ-phase (Mg28.6Zn63.8Gd7.7) with a hexagonal structure. The hardness of the IQC phase is higher than that of H1 phase, and both phases exhibit a higher hardness than the α-Mg matrix and the μ-phase. The elasticity of the H1 phase is superior to that of the α-Mg matrix. The IQC phase possesses a higher elastic modulus than H1 phase. The easily formed H1 phase exhibits the poorest plastic deformation capacity among these phases but a higher elastic modulus than the α-Mg matrix.
基金supported by the National High-Tech Research and Development Program of China(No.2006AA03Z115)the Major State Basic Research and Development Program of China(No.2006CB605203)
文摘The effect of injection pressure, piston velocity, and the forming temperature of semisolid slurry on the filling behavior of the semi-solid A356 aluminum alloy was investigated by simulation methods. The simulation results show that these processing parameters have an important effect on the filling behavior of the semi-solid A356 aluminum alloy. The slurry flows steadily in the cavity when the injection pressure, the piston velocity, and the forming temperature are low, but it is prone to turbulent flow when the injection pressure, the piston velocity, and the forming temperature are much higher. Therefore it is necessary to determine the appropriate processing parameters to get a steady flow of the slurry in the cavity.
基金financially supported by the National Basic Research Program of China (No. 2011CB606300)the National Natural Science Foundation of China (No. 5077400)
文摘In this study, a serpentine channel pouring process was used to prepare the semi-solid A1-20%Si alloy slurry and refine primary Si grains in the alloy. The effects of the pouring temperature, number of curves in the serpentine channel, and material of the serpentine channel on the size of primary Si grains in the semi-solid A1-20%Si alloy slurry were investigated. The results showed that the pouting temperature, number of the curves, and material of the channel strongly affected the size and distribution of the primary Si grains. The pouring tempera- ture exerted the strongest effect, followed by the number of the curves and then the material of the channel. Under experimental conditions of a four-curve copper channel and a pouring temperature of 701℃, primary Si grains in the semi-solid A1-20%Si alloy slurry were refined to the greatest extent, and the lath-like grains were changed into granular grains. Moreover, the equivalent grain diameter and the average shape coefficient of primary Si grains in the satisfactory semi-solid A1-20%Si alloy slurry were 24.4 μm and 0.89, respectively. Finally, the re- finement mechanism and distribution rule of primary Si grains in the slurry prepared through the serpentine channel pouring process were analyzed and discussed.
基金supported by the National Basic Research Program of China(2011CB606300)the National Natural Science Foundation of China(5077400)
文摘In this paper, the serpentine channel pouring process for preparing a semi-solid A390 alloy slurry and refining the primary Si grains of the A390 alloy, was used. The effects of the pouring temperature, the cooling water flow and the number of the curves on the size of the primary Si grains in the semi-solid A390 alloy slurry were investigated. The results show that the pouring temperature, the cooling water flow and the number of the curves have a major effect on the size and the distribution of primary Si grains. Under the experimental condition of the four-curve copper channel whose cooling water flow was 500 L·h-1 and the pouring temperature was 690 oC, the primary Si grains of the semi-solid A390 alloy slurry were refined to the greatest extent and the lath-like grains were changed into granular ones. Additionally, the equivalent grain diameter and the average shape factor of the primary Si grains of the satisfactory semi-solid A390 alloy slurry are 18.6 μm and 0.8, respectively. Further, the refinement mechanism of the primary Si grains through the serpentine channel pouring process was analyzed and discussed. In summary, the primary Si nuclei could be easily precipitated due to the chilling effect of the channel inner wall, thus the primary Si grains were greatly refined. Meanwhile, the subsequent alloy melt fluid also promoted the separation of primary Si grains from the inner wall, further refining the primary Si grains.
基金financially supported by the National Natural Science Foundation of China(Grant No.51701078)China Postdoctoral Science Foundation(Grant Nos.2018M632846 and 2018T110756)the Scientific Research Program of Hubei Provincial Education Department(Grant No.B2016053)
文摘The semisolid slurry of Al-Zn-Mg-Cu alloy was prepared through a self-designed water-cooled copper serpentine pouring channel(WSPC) machine. Influences of pouring temperature, the number of turns and the cooling water flow rate on the microstructure of the semisolid Al-Zn-Mg-Cu alloy slurry were investigated. The results show that the semisolid Al-Zn-Mg-Cu alloy slurry with satisfactory quality can be generated by the WSPC when the pouring temperature is in the range between 680 ℃ and 700 ℃. At a given pouring temperature, the average grain size of primary α-Al decreases and the shape factor increases with the increase of the number of turns. When the cooling water flow rate is 450 L·h^(-1), the obtained semisolid slurry is optimal. During the preparation of the semisolid Al-Zn-Mg-Cu alloy slurry with low superheat pouring, the alloy melt has mixed inhibition and convection flow characteristics by "self-stirring". When the alloy melt flows through the serpentine channel, the chilling effect of the inner wall of the channel, the convection and mixed inhibition of the alloy melt greatly promote the heterogeneous nucleation and grain segregation. This effect destroys the dendrite growth mode under traditional solidification conditions, and the primary nuclei gradually evolve into spherical or nearspherical grains.
基金the National High-Tech Research and Development Program of China (No.2006AA03Z115)the Major State Basic Research Development Program of China (No.2006CB605203)the National Natural Science Foundation of China (No.50774007)
文摘An apparent viscosity model of semi-solid A356 aluminum alloy has been developed and the software Castsofl6.0 coupled with the model has been used to simulate the mould filling of an automobile master brake cylinder with the semi-solid A356 aluminum alloy slurry. The simulation results are in agreement with the practical filling process, indicating that the apparent viscosity model is feasible and can be used to simulate the mould filling of the semisolid A356 aluminum alloy slurry and can be used to optimize the filling process and the design of dies. A higher injection pressure, a higher ingate flow velocity of the semi-solid slurry, and a higher slurry temperature are advantageous to the mould filling of the automobile master brake cylinder.
基金financially supported by the National Basic Research Program Priorities of China (No.2011CB606300)the National Natural Science Foundation of China (No.5077400)
文摘In this paper, the effects of rheo-diecast process parameters and T6 heat treatment on the microstructure and mechanical properties of the rheo-diecasting(RDC) semi-solid A390 alloy prepared through pure copper serpentine channel were investigated. The results indicate that the mechanical properties of the RDC samples change with the pouring temperature and injection pressure. In this case, a lower pouring temperature results in better tensile strength and elongation of the RDC A390 alloy; however, the tensile strength and elongation decrease when the pouring temperature decreases to 660°C. Higher injection pressures result in the improved mechanical properties of the RDC A390 alloy. To some extent, T6 heat treatment improves the tensile strength and ductility of the RDC A390 alloy compared to those of the non-heat treated alloy. However, when the pouring temperature and injection pressure are greater than 670°C and 70 MPa, respectively, the mechanical properties are sharply diminished.
基金The authors thank all patients and their families.The authors would like to acknowledge the editorial support provided by Keyra Martinez Dunn,MD,of Edanz(www.edanz.com),which was funded by Shanghai Roche Pharmaceutical Ltd.This study was funded by the Chinese Thoracic Oncology Group(CTONG),Shanghai Roche Pharmaceutical Ltd.
文摘EMERGING-CTONG 1103 showed improved progression-free survival(PFS)with neoadjuvant erlotinib vs.chemotherapy for patients harbouring EGFR sensibility mutations and R0 resected stage IIIA-N2 non-small cell lung cancer(NSCLC)(NCT01407822).Herein,we report the final results.Recruited patients were randomly allocated 1:1 to the erlotinib group(150 mg/day orally;neoadjuvant phase for 42 days and adjuvant phase to 12 months)or to the GC group(gemcitabine 1250 mg/m2 plus cisplatin 75 mg/m2 intravenously;2 cycles in neoadjuvant phase and 2 cycles in adjuvant phase).Objective response rate(ORR),complete pathologic response(pCR),PFS,and overall survival(OS)were assessed along with safety.Post hoc analysis was performed for subsequent treatments after disease recurrence.Among investigated 72 patients(erlotinib,n=37;GC,n=35),the median follow-up was 62.5 months.The median OS was 42.2 months(erlotinib)and 36.9 months(GC)(hazard ratio[HR],0.83;95%confidence interval[CI],0.47-1.47;p=0.513).The 3-and_(5-y)ear OS rates were 58.6%and 40.8%with erlotinib and 55.9%and 27.6%with GC(p_(3-y)=0.819,p_(5-y)=0.252).Subsequent treatment was administered in 71.9%and 81.8%of patients receiving erlotinib and GC,respectively;targeted therapy contributed mostly to OS(HR,0.35;95%CI,0.18-0.70).After disease progression,the ORR was 53.3%,and the median PFS was 10.9 months during the EGFR-TKI rechallenge.During postoperative therapy,grade 3 or 4 adverse events(AEs)were 13.5%in the erlotinib group and 29.4%in the GC group.No serious adverse events were observed.Erlotinib exhibited clinical feasibility for resectable IIIA-N2 NSCLC over chemotherapy in the neoadjuvant setting.
基金Item Sponsored by National High Technology Research and Development Program of China(2012AA03A505)
文摘Low-temperature slab-reheated grain-oriented silicon steel is characterized by a sharp {411}〈148〉 primary recrystallization texture. To date, the influence of this texture on secondary recrystallization is not clear. Microtextures in primary and secondary reerystallized sheets of low-temperature reheated grain-oriented silicon steel were examined using electron backscatter diffraction. By comparing the textures and microstructures of specific primary reerystallized grains neighboring secondary grains with those of other primary grains, the influences of primary re- crystallization textures and microstructures on the orientations of secondary grains were investigated. Results show that for low-temperature reheated graiworiented silicon steel, the primary recrystallization sheet comprises { 411 } 〈148〉, {111}〈112〉, and {001}〈120〉 texture componems. During secondary recrystallization, the {111}〈112〉 primary recrystallized grains were easily consumed by abnormally grown Goss, deviated Goss, Brass, or {210}〈001〉grains ;the { 411 }〈148〉 primary recrystallized grains were more resistant to being swallowed; and the {001} 〈120 grains were the most resistant to being consumed. For a particular primary grain, the distribution of its surrounding grain boundaries determined how easily it is consumed during secondary recrystallization. Primary grains surrounded by 20°- 45° grain boundaries were consumed much earlier than those having grain boundaries above 45°, which is in accordance with high-energy grain boundary theory. In addition, special ∑9 boundaries between {411}〈148〉 and Goss grains move more slowly than ∑9 boundaries between {111 }〈112〉 and Goss grains, which is attributed to the different positions of 〈110〉 rotation axis with respect to the normals of grain boundaries.
基金financially supported by the National High Technology Research and Development Program of China(Grant No.2012AA03A505)
文摘In this study, high- and low-grade grain-oriented electrical steels were used as the initial materials to produce 0.08-mm-thick sheet with one-step cold-rolling method. Electron backscattering diffraction analysis technique and X-ray diffraction texture analysis technique were adopted to investigate the effect of initial Goss texture sharpness on texture evolution and magnetic properties of ultra-thin grain-oriented electrical steel. The results showed that primary recrystal- lization and secondary recrystallization were the main processes that occurred during annealing. The induced factors for secondary recrystallization of two grades samples were not Consistent. The high-grade samples presented texture induction mechanism, while the low-grade samples revealed strong surface-energy induction mechanism. The initial Goss texture sharpness had a great impact on texture evolution and magnetic properties of ultra-thin grain-oriented electrical steel. The Goss texture component formed after primary recrystallization was stronger, and better magnetic properties were obtained at low frequencies. For low-grade samples, secondary recrystallization enhanced the intensity of Goss texture, and both grain size and texture contributed to better high-frequency magnetic properties after secondary recrystallization. By controlling the annealing process, the magnetic properties of low-grade products could be significantly improved, thus achieving conversion from low-grade to high-grade products.