The response wavelength of the blocked-impurity-band(BIB)structured infrared detector can reach 200µm,which is the most important very long wavelength infrared astronomical detector.The ion implantation method gr...The response wavelength of the blocked-impurity-band(BIB)structured infrared detector can reach 200µm,which is the most important very long wavelength infrared astronomical detector.The ion implantation method greatly simplifies the fabrication process of the device,but it is easy to cause lattice damage,introduce crystalline defects,and lead to the increase of the dark current of detectors.Herein,the boron-doped germanium ion implantation process was studied,and the involved lattice damage mechanism was discussed.Experimental conditions involved using 80 keV energy for boron ion implantation,with doses ranging from 1×10^(13)cm^(-2)to 3×10^(15)cm^(-2).After implantation,thermal annealing at 450℃was implemented to optimize dopant activation and mitigate the effects of ion implantation.Various sophisticated characterization techniques,including X-ray dif⁃fraction(XRD),Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),and secondary ion mass spec⁃trometry(SIMS)were used to clarify lattice damage.At lower doses,no notable structural alterations were ob⁃served.However,as the dosage increased,specific micro distortions became apparent,which could be attributed to point defects and residual strain.The created lattice damage was recovered by thermal treatment,however,an irreversible strain induced by implantation still existed at heavily dosed samples.展开更多
Nanocomposite multilayer TiBN coatings were prepared on Si(100) and 9Cr18Mo substrates using TiBN composite cathode plasma immersion ion implantation and deposition technique(PIIID). Synthesis of TiBN composite cathod...Nanocomposite multilayer TiBN coatings were prepared on Si(100) and 9Cr18Mo substrates using TiBN composite cathode plasma immersion ion implantation and deposition technique(PIIID). Synthesis of TiBN composite cathodes was conducted by powder metallurgy technology and the content of hexagonal boron nitride(h-BN) was changed from 8% to 40%(mass fraction). The as-deposited coatings were characterized by energy dispersive spectrometer(EDS), grazing incidence X-ray diffraction(GIXRD), Fourier Transform Infrared Spectroscopy(FTIR) and high resolution transmission electron microcopy(HRTEM). EDS results show that the B content of the coatings was varied from 3.71% to 13.84%(molar fraction) when the composition of the h-BN in the composited cathodes was changed from 8 % to 40%(mass fraction). GIXRD results reveal that the TiBN coatings with a B content of 8% has the main diffraction peak of TiN(200),(220) and(311), and these peaks disappear when the B content is increased. FTIR analysis of the multilayer coatings showed the presence of h-BN in all coatings. TEM images reveal that all coatings have the characteristics of self-forming nanocomposite multilayers, where the nanocomposites are composed of face-centered cubic Ti N or h-BN nanocrystalline embedded in amorphous matrix. The tribological tests reveal that the Ti BN coatings exhibit a marked decrease of coefficient at room temperature(~0.25). The improved properties were found to be derived from the comprehensiveness of the self-forming multilayers structure and the h-BN solid lubrication effects in the coatings.展开更多
To investigate the expression of Prominin-1(Prom-1)in mouse uterus during peri-implantation.In situ hybridization and immunohistochemical staining were used to detect the mRNA and protein expression level of Prom-1 in...To investigate the expression of Prominin-1(Prom-1)in mouse uterus during peri-implantation.In situ hybridization and immunohistochemical staining were used to detect the mRNA and protein expression level of Prom-1 in mice uterus in early pregnancy,pseudopregnancy,estrous cycle,treated with hormone,delayed implantation and activation models.The results showed that Prom-1 was gradually weakened in uterine luminal epithelium(LE)and glandular epithelium(GE)during days 1-4 of pregnancy.During days 5-8,Prom-1 was strongly expressed in GE,and signal of Prom-1 protein was detected in matrix and decidua around the embryo.Similar to pregnancy,Prom-1 was strongly expressed in LE and GE on the 1st day and weakly expressed on the 4th day of pseudopregnancy.In addition,Prom-1 was highly expressed in LE and GE on estrus.Expression of Prom-1 was observed in the LE and the GE of delayed-implantation uterus.In activated-implantation animal model,Prom-1 was strongly expressed in the GE.In the hormone-treated model,Prom-1 expression levels were higher in the uterus of the 17β-estradiol-treated group than those in the control group.These results indicated that Prom-1 might promote the proliferation of mouse endometrial epithelium and participate in the establishment of uterine receptivity.Meanwhile,the expression of Prom-1 was up-regulated by the 17β-estradiol,indicating that Prom-1 might involve in the process of decidua development regulated by uterine glands,and Prom-1 might play an important role in mice early pregnancy.展开更多
Lipopolysaccharide-binding protein(LBP)functions as an acute phase protein and plays a role in the innate immune response to bacterial challenge.To investigate the uterine expression of LBP during peri-implantation in...Lipopolysaccharide-binding protein(LBP)functions as an acute phase protein and plays a role in the innate immune response to bacterial challenge.To investigate the uterine expression of LBP during peri-implantation in mice,in situ hybridization and immunohistochemical staining were used to detect the mRNA and protein expression of LBP in mouse uteri in the early pregnancy,pseudopregnancy,artificial decidualization and hormone-treated mice.The results showed that LBP was expressed in uterine luminal epithelium(LE)and glandular epithelium(GE)during days 1-4 of pregnancy.During days 5-8,LBP was weakly expressed in the decidual cells around the embryo on the 5th day of pregnancy(implantation occurred),then gradually increased,LBP was strongly expressed in the decidual zone on the 8th day of pregnancy.The expression of LBP in pseudopregnancy was similar with pregnancy on days 1-4.In artificial decidualization mice,LBP was observed in uterine LE and GE in the control horn,whereas LBP expression was significantly higher in decidua of mouse uteri under artificial decidualization.In hormone-treated mice,the expression of LBP wasup-regulated by 17β-estradiol(E2)and progesterone(P4).In addition,the cultured mouse endometrial stromal cells(mESCs)were induced for in vitro decidualization with 10 nmol·L-1 E2 and 1μmol·L-1 P4.Real-time PCR results showed that LBP mRNA expression was highly induced in mESCs after decidual stimulus.In vivo and in vitro experiments showed that LBP was expressed in the decidual cells,indicating that LBP involved in decidualization of mouse uteri.展开更多
The surface layer of beryllium, specimen, has been strengthened by ion implantation. Its microhardness was measured. The hardness of surface layer has been calculated from the microhardness. The experimental data of t...The surface layer of beryllium, specimen, has been strengthened by ion implantation. Its microhardness was measured. The hardness of surface layer has been calculated from the microhardness. The experimental data of the wear rate indirectly Confirmed the reasonableness of the result of calculation. It is shown that the hardness of the surface layer strengthened, by ion implantation is nine times higher than that of beryllium itself. The relation between hardness and implantation dose was analysed and the best dose was obtained.展开更多
Objective To compare the efficacy of toric implantable collamer lens(Toric-ICL)and femtosecond laser-assisted in situ keratomileusis(FS-LASIK)for myopia correction in patients with moderate to high myopia complicated ...Objective To compare the efficacy of toric implantable collamer lens(Toric-ICL)and femtosecond laser-assisted in situ keratomileusis(FS-LASIK)for myopia correction in patients with moderate to high myopia complicated with astigmatism.Methods We retrospectively collected data from 64 patients(aged 18-42 years)with moderate to high myopia complicated with astigmatism(128 eyes)undergoing either Toric-ICL(28 patients/56 eyes)or FS-LASIK(36 patients/72 eyes)at our department between January,2019 and December,2020.The changes of uncorrected distance visual acuity(UCVA),spherical equivalent(SE),mean astigmatism correction index(CI),corneal endothelial cell density(ECD)and intraocular pressure(IOP)following the procedures were compared between the two groups.Results In FS-LASIK group,all the eyes(72/72)achieved an UCVA≥1.0,similar to the rate in Toric-ICL group(55/56 eyes;P=0.2374).The postoperative SE was also comparable between FS-LASIK and Toric-ICL groups[0.43±0.06 D(range:-1.0 to 1.50 D)vs 0.38±0.05 D(range:-0.75 to 1.00 D);P=0.56].The mean astigmatism CI was significantly higher in FS-LASIK group than in Toric-ICL group(0.8561 vs 0.7176;P<0.0001),and 88.89%of the eyes in FS-LASIK group and 69.64%in Toric-ICL group had postoperative astigmatism≤0.50 D.No significant changes were observed in postoperative corneal ECD in FS-LASIK group,whereas ECD decreased significantly after the procedure in Toric-ICL group(P=0.0057).The patients undergoing Toric-ICL exhibited no significant changes of postoperative IOP,but the patients receiving FS-LASIK had significantly reduced IOP after the procedure(P<0.001).Conclusion Although the patients included in Toric-ICL group had higher myopia and astigmatism,Toric-ICL still showed better predictability and efficacy for astigmatic correction in Toric-ICL group.Toric-ICL is an effective and safe equivalent of FS-LASIK for correcting moderate myopia but can be more advantageous for correcting high myopia with astigmatism.展开更多
In this study,Mg-based composites,by the addition of ZnO,Ca_(2)ZnSi_(2)O_(7),Ca_(2)MgSi_(2)O_(7),and CaSiO_(3)as bioactive agents,were fabricated using friction stir processing.The microstructure and in vitro assessme...In this study,Mg-based composites,by the addition of ZnO,Ca_(2)ZnSi_(2)O_(7),Ca_(2)MgSi_(2)O_(7),and CaSiO_(3)as bioactive agents,were fabricated using friction stir processing.The microstructure and in vitro assessment of bioactivity,biodegradation rate,and corrosion behavior of the resultant composites were investigated in simulated body fluid(SBF).The results showed that during the immersion of composites in SBF for 28 d,due to the release of Ca^(2+)and PO_(4)^(3-)ions,hydroxyapatite(HA)crystals with cauliflower shaped morphology were deposited on the surface of composites,confirming good bioactivity of composites.In addition,due to the uniform distribution of bioceramic powders throughout Mg matrix,grain refinement of the Mg matrix,and uniform redistribution of secondary phase particles,the polarization resistance increased,and the biodegradation rate of composites significantly reduced compared to monolithic Mg matrix.The polarization corrosion resistance of Mg-ZnO increased from 0.216 to 2.499 kΩ/cm^(2)compared to monolithic Mg alloy.Additionally,Mg-ZnO composite with the weight loss of 0.0217 g after 28 d immersion showed lower weight loss compared to other samples with increasing immersion time.Moreover,Mg-ZnO composite with the biodegradation rate of 37.71 mm/a exhibited lower biodegradation rate compared to other samples with increasing immersion time.展开更多
Nanocrystalline Fe-doped TiO2 with size of 6070 nm was prepared by a sol-gel technique, followed by freeze-drying treatment for 2 h. Thermogravimetric and differential thermal analyses, X-ray diffraction, scanning （e...Nanocrystalline Fe-doped TiO2 with size of 6070 nm was prepared by a sol-gel technique, followed by freeze-drying treatment for 2 h. Thermogravimetric and differential thermal analyses, X-ray diffraction, scanning （electron） microscope, laser diffraction particle size analyzer and UV-Vis spectrophotometer technologies were used to characterize the product. The photocatalytic activities of the samples were evaluated by the degradation of wastewater of paper-making. The effects of Fe ion implantation on the photocatalytic activity of TiO2 were also discussed. The results show that the iron content plays an essential role in affecting the photocatalytic activity of the Fe-doped TiO2 and the optimum content of Fe-doped is 0.05% （mass fraction）. The photocatalytic activity of samples with lower content of Fe-doped is higher than that of pure TiO2 in the treatment of paper-making wastewater. The photo-degradation effect of paper-making effluent is the best by means of Fe-doped TiO2 with 0.05% Fe.展开更多
Secondary ion mass spectrometry (SIMS) is a standard technique for characterization of dopant distribution in semiconductor industry. In the ultra-shallow junction (USJ) application, the interested depth scale was ext...Secondary ion mass spectrometry (SIMS) is a standard technique for characterization of dopant distribution in semiconductor industry. In the ultra-shallow junction (USJ) application, the interested depth scale was extended into the surface transient area of SIMS. There is several improved approach reviewed in this paper that can meet the requirements for the USJ characterization. Sputtering with a low energy primary ion beam incident at a large angle respect to the simple surface normal can effectively minimize the depth of the surface transient area, as well as the length of the profile tail. Oxygen leak can reduce the transient ion yield change, but induces lower depth resolution. Quadrupole SIMS can be used in B profile. As and P profiles, however, need magnetic analyzer with higher mass resolution.展开更多
Effects of fibroblast-mediated IL-2 and IL-3 genetherapy on recovery of bone marrow depression in tumor-bearing mice treated with cyclophosphamide (300 mg/kg) and syngeneic BMT were investigated in the presentreport. ...Effects of fibroblast-mediated IL-2 and IL-3 genetherapy on recovery of bone marrow depression in tumor-bearing mice treated with cyclophosphamide (300 mg/kg) and syngeneic BMT were investigated in the presentreport. BALB/c mice were inoculated with J558Lplasmacytoma cells s. c. and 3 days later IL-2 secretingNIH3T3-IL-2, IL-3 secreting NIH3T3-IL-3 fibroblastcells were implanted into the tumor-bearing mice展开更多
bHLH transcript factor superfamily members involve in various bio-events in mice. According to existing researches, there are six members of bHLH superfamily likely to participate in the uterine development during ear...bHLH transcript factor superfamily members involve in various bio-events in mice. According to existing researches, there are six members of bHLH superfamily likely to participate in the uterine development during early pregnancy in mice. Expression of six members of bHLH superfamily Hes6, Tcf23, Twist1, Twist2, Mitf and Tead4 in mouse uterus in early pregnancy was detected by RT-qPCR. All the six genes were expressed in early pregnancy mouse uterus, and expression pattern of each one was different from others. In situ hybridization results showed that Tead4 was expressed in decidual tissues of the 8th day pregnancy mouse. Tead4 might be involved in the regulation of embryo implantation in mice.展开更多
Artificial bone with porous structure is crucial for tissue scaffold and clinic implants.Scaffold provides structure support for cells and guides tissues regeneration for final tissue structure.A computational aided p...Artificial bone with porous structure is crucial for tissue scaffold and clinic implants.Scaffold provides structure support for cells and guides tissues regeneration for final tissue structure.A computational aided process of porous bone modeling was developed which described the design and fabrication of tissue scaffolds by considering intricate architecture,porosity and pore size.To simulate intricate bone structure,different constructive units were presented.In modeling process,bone contour was gotten from computed tomography(CT)images and was divided into two levels.Each level was represented by relatively reconstructive process.Pore size distribution was controlled by using mesh generation.The whole hexahedral mesh was reduced by unit structure,when a 3D mesh with various hexahedral elements was provided.The simulation results show that constructive structure of porous scaffold can meet the needs of clinic implants in accurate and controlled way.展开更多
Functionalized implants demonstrate an upgraded approach in orthopedic implants,aiming to achieve long term success through improved bio integration.Bioceramic coatings with multifunctionality have arisen as an effect...Functionalized implants demonstrate an upgraded approach in orthopedic implants,aiming to achieve long term success through improved bio integration.Bioceramic coatings with multifunctionality have arisen as an effective substitute for conventional coatings,owing to their combination of various properties that are essential for bio-implants,such as osteointegration and antibacterial character.In the present study,thin hopeite coatings were produced by Pulsed laser deposition(PLD)and radio frequency magnetron sputtering(RFMS)on Ti64 substrates.The obtained hopeite coatings were annealed at 500°C in ambient air and studied in terms of surface morphology,phase composition,surface roughness,adhesion strength,antibacterial efficacy,apatite forming ability,and surface wettability by scanning electron microscope(SEM),X-ray diffraction(XRD),atomic force microscope(AFM),tensometer,fluorescence-activated cell sorting(FACS),simulated body fluid(SBF)immersion test and contact angle goniometer,respectively.Furthermore,based on promising results obtained in the present work it can be summarized that the new generation multifunctional hopeite coating synthesized by two alternative new process routes of PLD and RFMS on Ti64 substrates,provides effective alternatives to conventional coatings,largely attributed to strong osteointegration and antibacterial character of deposited hopeite coating ensuring the overall stability of metallic orthopedic implants.展开更多
DMR-249 A is an indigenously developed high strength low alloy steel for Indian ship building industry for making ship-hull and is extensively used in the construction of war ships and submarines. Welding electrodes c...DMR-249 A is an indigenously developed high strength low alloy steel for Indian ship building industry for making ship-hull and is extensively used in the construction of war ships and submarines. Welding electrodes conforming to SFA 5.5 AWS E8018 C1 has been indigenously developed for welding of this steel using shielded metal arc welding process. In the present study, susceptibility to hydrogen assisted cracking of DMR-249 A steel welds made using this electrode has been assessed using implant test. Implant tests were conducted using this electrode at two different levels of diffusible hydrogen, measured using gas chromatography technique. It is observed that both the steel and the welding consumable are not susceptible to hydrogen assisted cracking even with a high diffusible hydrogen level of 9 m L/100 g of weld metal. In implant tests, specimen did not fracture even after loading to stress levels higher than the yield strength of the base metal. The good resistance of this steel and the welding consumable, even with high levels of diffusible hydrogen, is attributed to absence of a susceptible microstructure in both the weld metal and heat affected zone. Hence, this study shows that, in the absence of a susceptible microstructure, hydrogen assisted cracking is unlikely to occur even if hydrogen level is high. It also confirms that in welding of DMR-249 A with indigenously developed E8018 C1 electrode, hydrogen assisted cracking is not a concern and no preheating is required to avoid it during welding.展开更多
1.Introduction Biodegradable polymeric biomaterials have been fabricated into various biomedical implants such as drug delivery nanoparticles,tissue engineering scaffolds and orthopedic devices.Using biodegradable pol...1.Introduction Biodegradable polymeric biomaterials have been fabricated into various biomedical implants such as drug delivery nanoparticles,tissue engineering scaffolds and orthopedic devices.Using biodegradable polymers as implant materials is beneficial as the implants are degraded and cleared by the body once their missions are complete,leaving no foreign materials in the body.Driven by the versatile needs in biomedical engineering,searching for ideal functional biodegradable polymers has been an endless effort in the past decades.Among biodegradable polymers,citrate-based biodegradable elastomeric(CABE)polymers have recently received increasing attention because their compliance under force can closely resemble the elastic展开更多
Background Dental implants have been widely used in the last few decades.However,patients with insufficient bone height need reconstructive surgeries before implant insertion.Distraction implant(Dl)has been invented t...Background Dental implants have been widely used in the last few decades.However,patients with insufficient bone height need reconstructive surgeries before implant insertion.Distraction implant(Dl)has been invented to simplify the treatment procedure,but the shortcomings of Dl have limited its clinical use.We introduced biodegradable polyester to a novel Dl,called biodegradable interference distraction implant(BIDI).The purpose of this study was to assess the radiological,histological,and biomechanical properties of BIDI in animal models.Methods BIDIs were manufactured and inserted into the atrophied mandibles of 6 dogs.展开更多
基金Supported by National Key R&D Program of China(2023YFA1608701)National Natural Science Foundation of China(62274168,11933006,U2141240)Hangzhou Leading Innovation and Entrepreneurship Team(TD2020002)。
文摘The response wavelength of the blocked-impurity-band(BIB)structured infrared detector can reach 200µm,which is the most important very long wavelength infrared astronomical detector.The ion implantation method greatly simplifies the fabrication process of the device,but it is easy to cause lattice damage,introduce crystalline defects,and lead to the increase of the dark current of detectors.Herein,the boron-doped germanium ion implantation process was studied,and the involved lattice damage mechanism was discussed.Experimental conditions involved using 80 keV energy for boron ion implantation,with doses ranging from 1×10^(13)cm^(-2)to 3×10^(15)cm^(-2).After implantation,thermal annealing at 450℃was implemented to optimize dopant activation and mitigate the effects of ion implantation.Various sophisticated characterization techniques,including X-ray dif⁃fraction(XRD),Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),and secondary ion mass spec⁃trometry(SIMS)were used to clarify lattice damage.At lower doses,no notable structural alterations were ob⁃served.However,as the dosage increased,specific micro distortions became apparent,which could be attributed to point defects and residual strain.The created lattice damage was recovered by thermal treatment,however,an irreversible strain induced by implantation still existed at heavily dosed samples.
基金Projects(21573054,21327002,51401201)supported by the National Natural Science Foundation of ChinaProject(U1537214)supported by the Joint Funds Key Project of the National Natural Science Foundation of ChinaProject(51535003)supported by the State Key Program of National Natural Science of China
文摘Nanocomposite multilayer TiBN coatings were prepared on Si(100) and 9Cr18Mo substrates using TiBN composite cathode plasma immersion ion implantation and deposition technique(PIIID). Synthesis of TiBN composite cathodes was conducted by powder metallurgy technology and the content of hexagonal boron nitride(h-BN) was changed from 8% to 40%(mass fraction). The as-deposited coatings were characterized by energy dispersive spectrometer(EDS), grazing incidence X-ray diffraction(GIXRD), Fourier Transform Infrared Spectroscopy(FTIR) and high resolution transmission electron microcopy(HRTEM). EDS results show that the B content of the coatings was varied from 3.71% to 13.84%(molar fraction) when the composition of the h-BN in the composited cathodes was changed from 8 % to 40%(mass fraction). GIXRD results reveal that the TiBN coatings with a B content of 8% has the main diffraction peak of TiN(200),(220) and(311), and these peaks disappear when the B content is increased. FTIR analysis of the multilayer coatings showed the presence of h-BN in all coatings. TEM images reveal that all coatings have the characteristics of self-forming nanocomposite multilayers, where the nanocomposites are composed of face-centered cubic Ti N or h-BN nanocrystalline embedded in amorphous matrix. The tribological tests reveal that the Ti BN coatings exhibit a marked decrease of coefficient at room temperature(~0.25). The improved properties were found to be derived from the comprehensiveness of the self-forming multilayers structure and the h-BN solid lubrication effects in the coatings.
基金Supported by the National Natural Science Foundation of China(31472097)
文摘To investigate the expression of Prominin-1(Prom-1)in mouse uterus during peri-implantation.In situ hybridization and immunohistochemical staining were used to detect the mRNA and protein expression level of Prom-1 in mice uterus in early pregnancy,pseudopregnancy,estrous cycle,treated with hormone,delayed implantation and activation models.The results showed that Prom-1 was gradually weakened in uterine luminal epithelium(LE)and glandular epithelium(GE)during days 1-4 of pregnancy.During days 5-8,Prom-1 was strongly expressed in GE,and signal of Prom-1 protein was detected in matrix and decidua around the embryo.Similar to pregnancy,Prom-1 was strongly expressed in LE and GE on the 1st day and weakly expressed on the 4th day of pseudopregnancy.In addition,Prom-1 was highly expressed in LE and GE on estrus.Expression of Prom-1 was observed in the LE and the GE of delayed-implantation uterus.In activated-implantation animal model,Prom-1 was strongly expressed in the GE.In the hormone-treated model,Prom-1 expression levels were higher in the uterus of the 17β-estradiol-treated group than those in the control group.These results indicated that Prom-1 might promote the proliferation of mouse endometrial epithelium and participate in the establishment of uterine receptivity.Meanwhile,the expression of Prom-1 was up-regulated by the 17β-estradiol,indicating that Prom-1 might involve in the process of decidua development regulated by uterine glands,and Prom-1 might play an important role in mice early pregnancy.
基金Supported by the National Natural Science Foundation of China(31472097)。
文摘Lipopolysaccharide-binding protein(LBP)functions as an acute phase protein and plays a role in the innate immune response to bacterial challenge.To investigate the uterine expression of LBP during peri-implantation in mice,in situ hybridization and immunohistochemical staining were used to detect the mRNA and protein expression of LBP in mouse uteri in the early pregnancy,pseudopregnancy,artificial decidualization and hormone-treated mice.The results showed that LBP was expressed in uterine luminal epithelium(LE)and glandular epithelium(GE)during days 1-4 of pregnancy.During days 5-8,LBP was weakly expressed in the decidual cells around the embryo on the 5th day of pregnancy(implantation occurred),then gradually increased,LBP was strongly expressed in the decidual zone on the 8th day of pregnancy.The expression of LBP in pseudopregnancy was similar with pregnancy on days 1-4.In artificial decidualization mice,LBP was observed in uterine LE and GE in the control horn,whereas LBP expression was significantly higher in decidua of mouse uteri under artificial decidualization.In hormone-treated mice,the expression of LBP wasup-regulated by 17β-estradiol(E2)and progesterone(P4).In addition,the cultured mouse endometrial stromal cells(mESCs)were induced for in vitro decidualization with 10 nmol·L-1 E2 and 1μmol·L-1 P4.Real-time PCR results showed that LBP mRNA expression was highly induced in mESCs after decidual stimulus.In vivo and in vitro experiments showed that LBP was expressed in the decidual cells,indicating that LBP involved in decidualization of mouse uteri.
基金This project was suportod by Reijing Zhongguancun Associated Center of Analysis and Measurement
文摘The surface layer of beryllium, specimen, has been strengthened by ion implantation. Its microhardness was measured. The hardness of surface layer has been calculated from the microhardness. The experimental data of the wear rate indirectly Confirmed the reasonableness of the result of calculation. It is shown that the hardness of the surface layer strengthened, by ion implantation is nine times higher than that of beryllium itself. The relation between hardness and implantation dose was analysed and the best dose was obtained.
文摘Objective To compare the efficacy of toric implantable collamer lens(Toric-ICL)and femtosecond laser-assisted in situ keratomileusis(FS-LASIK)for myopia correction in patients with moderate to high myopia complicated with astigmatism.Methods We retrospectively collected data from 64 patients(aged 18-42 years)with moderate to high myopia complicated with astigmatism(128 eyes)undergoing either Toric-ICL(28 patients/56 eyes)or FS-LASIK(36 patients/72 eyes)at our department between January,2019 and December,2020.The changes of uncorrected distance visual acuity(UCVA),spherical equivalent(SE),mean astigmatism correction index(CI),corneal endothelial cell density(ECD)and intraocular pressure(IOP)following the procedures were compared between the two groups.Results In FS-LASIK group,all the eyes(72/72)achieved an UCVA≥1.0,similar to the rate in Toric-ICL group(55/56 eyes;P=0.2374).The postoperative SE was also comparable between FS-LASIK and Toric-ICL groups[0.43±0.06 D(range:-1.0 to 1.50 D)vs 0.38±0.05 D(range:-0.75 to 1.00 D);P=0.56].The mean astigmatism CI was significantly higher in FS-LASIK group than in Toric-ICL group(0.8561 vs 0.7176;P<0.0001),and 88.89%of the eyes in FS-LASIK group and 69.64%in Toric-ICL group had postoperative astigmatism≤0.50 D.No significant changes were observed in postoperative corneal ECD in FS-LASIK group,whereas ECD decreased significantly after the procedure in Toric-ICL group(P=0.0057).The patients undergoing Toric-ICL exhibited no significant changes of postoperative IOP,but the patients receiving FS-LASIK had significantly reduced IOP after the procedure(P<0.001).Conclusion Although the patients included in Toric-ICL group had higher myopia and astigmatism,Toric-ICL still showed better predictability and efficacy for astigmatic correction in Toric-ICL group.Toric-ICL is an effective and safe equivalent of FS-LASIK for correcting moderate myopia but can be more advantageous for correcting high myopia with astigmatism.
文摘In this study,Mg-based composites,by the addition of ZnO,Ca_(2)ZnSi_(2)O_(7),Ca_(2)MgSi_(2)O_(7),and CaSiO_(3)as bioactive agents,were fabricated using friction stir processing.The microstructure and in vitro assessment of bioactivity,biodegradation rate,and corrosion behavior of the resultant composites were investigated in simulated body fluid(SBF).The results showed that during the immersion of composites in SBF for 28 d,due to the release of Ca^(2+)and PO_(4)^(3-)ions,hydroxyapatite(HA)crystals with cauliflower shaped morphology were deposited on the surface of composites,confirming good bioactivity of composites.In addition,due to the uniform distribution of bioceramic powders throughout Mg matrix,grain refinement of the Mg matrix,and uniform redistribution of secondary phase particles,the polarization resistance increased,and the biodegradation rate of composites significantly reduced compared to monolithic Mg matrix.The polarization corrosion resistance of Mg-ZnO increased from 0.216 to 2.499 kΩ/cm^(2)compared to monolithic Mg alloy.Additionally,Mg-ZnO composite with the weight loss of 0.0217 g after 28 d immersion showed lower weight loss compared to other samples with increasing immersion time.Moreover,Mg-ZnO composite with the biodegradation rate of 37.71 mm/a exhibited lower biodegradation rate compared to other samples with increasing immersion time.
文摘Nanocrystalline Fe-doped TiO2 with size of 6070 nm was prepared by a sol-gel technique, followed by freeze-drying treatment for 2 h. Thermogravimetric and differential thermal analyses, X-ray diffraction, scanning （electron） microscope, laser diffraction particle size analyzer and UV-Vis spectrophotometer technologies were used to characterize the product. The photocatalytic activities of the samples were evaluated by the degradation of wastewater of paper-making. The effects of Fe ion implantation on the photocatalytic activity of TiO2 were also discussed. The results show that the iron content plays an essential role in affecting the photocatalytic activity of the Fe-doped TiO2 and the optimum content of Fe-doped is 0.05% （mass fraction）. The photocatalytic activity of samples with lower content of Fe-doped is higher than that of pure TiO2 in the treatment of paper-making wastewater. The photo-degradation effect of paper-making effluent is the best by means of Fe-doped TiO2 with 0.05% Fe.
文摘Secondary ion mass spectrometry (SIMS) is a standard technique for characterization of dopant distribution in semiconductor industry. In the ultra-shallow junction (USJ) application, the interested depth scale was extended into the surface transient area of SIMS. There is several improved approach reviewed in this paper that can meet the requirements for the USJ characterization. Sputtering with a low energy primary ion beam incident at a large angle respect to the simple surface normal can effectively minimize the depth of the surface transient area, as well as the length of the profile tail. Oxygen leak can reduce the transient ion yield change, but induces lower depth resolution. Quadrupole SIMS can be used in B profile. As and P profiles, however, need magnetic analyzer with higher mass resolution.
文摘Effects of fibroblast-mediated IL-2 and IL-3 genetherapy on recovery of bone marrow depression in tumor-bearing mice treated with cyclophosphamide (300 mg/kg) and syngeneic BMT were investigated in the presentreport. BALB/c mice were inoculated with J558Lplasmacytoma cells s. c. and 3 days later IL-2 secretingNIH3T3-IL-2, IL-3 secreting NIH3T3-IL-3 fibroblastcells were implanted into the tumor-bearing mice
基金Supported by the National Transgenic Major Projects of China(2011ZX08007-002)
文摘bHLH transcript factor superfamily members involve in various bio-events in mice. According to existing researches, there are six members of bHLH superfamily likely to participate in the uterine development during early pregnancy in mice. Expression of six members of bHLH superfamily Hes6, Tcf23, Twist1, Twist2, Mitf and Tead4 in mouse uterus in early pregnancy was detected by RT-qPCR. All the six genes were expressed in early pregnancy mouse uterus, and expression pattern of each one was different from others. In situ hybridization results showed that Tead4 was expressed in decidual tissues of the 8th day pregnancy mouse. Tead4 might be involved in the regulation of embryo implantation in mice.
基金Project(2011DFB70230)supported by State International Cooperation Program of ChinaProject(N110403003)supported by Basic Research Foundation of Education Ministry of China
文摘Artificial bone with porous structure is crucial for tissue scaffold and clinic implants.Scaffold provides structure support for cells and guides tissues regeneration for final tissue structure.A computational aided process of porous bone modeling was developed which described the design and fabrication of tissue scaffolds by considering intricate architecture,porosity and pore size.To simulate intricate bone structure,different constructive units were presented.In modeling process,bone contour was gotten from computed tomography(CT)images and was divided into two levels.Each level was represented by relatively reconstructive process.Pore size distribution was controlled by using mesh generation.The whole hexahedral mesh was reduced by unit structure,when a 3D mesh with various hexahedral elements was provided.The simulation results show that constructive structure of porous scaffold can meet the needs of clinic implants in accurate and controlled way.
文摘Functionalized implants demonstrate an upgraded approach in orthopedic implants,aiming to achieve long term success through improved bio integration.Bioceramic coatings with multifunctionality have arisen as an effective substitute for conventional coatings,owing to their combination of various properties that are essential for bio-implants,such as osteointegration and antibacterial character.In the present study,thin hopeite coatings were produced by Pulsed laser deposition(PLD)and radio frequency magnetron sputtering(RFMS)on Ti64 substrates.The obtained hopeite coatings were annealed at 500°C in ambient air and studied in terms of surface morphology,phase composition,surface roughness,adhesion strength,antibacterial efficacy,apatite forming ability,and surface wettability by scanning electron microscope(SEM),X-ray diffraction(XRD),atomic force microscope(AFM),tensometer,fluorescence-activated cell sorting(FACS),simulated body fluid(SBF)immersion test and contact angle goniometer,respectively.Furthermore,based on promising results obtained in the present work it can be summarized that the new generation multifunctional hopeite coating synthesized by two alternative new process routes of PLD and RFMS on Ti64 substrates,provides effective alternatives to conventional coatings,largely attributed to strong osteointegration and antibacterial character of deposited hopeite coating ensuring the overall stability of metallic orthopedic implants.
文摘DMR-249 A is an indigenously developed high strength low alloy steel for Indian ship building industry for making ship-hull and is extensively used in the construction of war ships and submarines. Welding electrodes conforming to SFA 5.5 AWS E8018 C1 has been indigenously developed for welding of this steel using shielded metal arc welding process. In the present study, susceptibility to hydrogen assisted cracking of DMR-249 A steel welds made using this electrode has been assessed using implant test. Implant tests were conducted using this electrode at two different levels of diffusible hydrogen, measured using gas chromatography technique. It is observed that both the steel and the welding consumable are not susceptible to hydrogen assisted cracking even with a high diffusible hydrogen level of 9 m L/100 g of weld metal. In implant tests, specimen did not fracture even after loading to stress levels higher than the yield strength of the base metal. The good resistance of this steel and the welding consumable, even with high levels of diffusible hydrogen, is attributed to absence of a susceptible microstructure in both the weld metal and heat affected zone. Hence, this study shows that, in the absence of a susceptible microstructure, hydrogen assisted cracking is unlikely to occur even if hydrogen level is high. It also confirms that in welding of DMR-249 A with indigenously developed E8018 C1 electrode, hydrogen assisted cracking is not a concern and no preheating is required to avoid it during welding.
基金supported in part by a NSF CAREER award(1313553)a NIH R01 award (EB012575)+2 种基金a NSF collaborative research award(1266116)a CPRIT High Impact/High Risk Research Award(RP110412)a research award from National Natural Sciences Foundation of China(31228007)
文摘1.Introduction Biodegradable polymeric biomaterials have been fabricated into various biomedical implants such as drug delivery nanoparticles,tissue engineering scaffolds and orthopedic devices.Using biodegradable polymers as implant materials is beneficial as the implants are degraded and cleared by the body once their missions are complete,leaving no foreign materials in the body.Driven by the versatile needs in biomedical engineering,searching for ideal functional biodegradable polymers has been an endless effort in the past decades.Among biodegradable polymers,citrate-based biodegradable elastomeric(CABE)polymers have recently received increasing attention because their compliance under force can closely resemble the elastic
基金supported by the National Natural Science Foundation of China(No. 30900284,No.31100668,and No.31070873)
文摘Background Dental implants have been widely used in the last few decades.However,patients with insufficient bone height need reconstructive surgeries before implant insertion.Distraction implant(Dl)has been invented to simplify the treatment procedure,but the shortcomings of Dl have limited its clinical use.We introduced biodegradable polyester to a novel Dl,called biodegradable interference distraction implant(BIDI).The purpose of this study was to assess the radiological,histological,and biomechanical properties of BIDI in animal models.Methods BIDIs were manufactured and inserted into the atrophied mandibles of 6 dogs.
