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The predictive value of NLR and SII in anti⁃MDA5 antibody⁃positive dermatomyositis with rapidly progressive interstitial lung disease
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作者 CAI Qingqing YOU Hanxiao +7 位作者 WANG Lei LÜChengyin SHI Yumeng QIU Yulu WU Lingyun WANG Fang ZHANG Miaojia TAN Wenfeng 《南京医科大学学报(自然科学版)》 北大核心 2025年第2期196-207,共12页
Objective:To evaluate the predictive value of the neutrophil⁃to⁃lymphocyte ratio(NLR)and the systemic immune⁃inflammation index(SII)in predicting patients with anti⁃melanoma differentiation⁃associated gene 5⁃positive(... Objective:To evaluate the predictive value of the neutrophil⁃to⁃lymphocyte ratio(NLR)and the systemic immune⁃inflammation index(SII)in predicting patients with anti⁃melanoma differentiation⁃associated gene 5⁃positive(anti⁃MDA5+)dermatomyositis(DM)develop into the rapidly progressive interstitial lung disease(RPILD).Methods:We retrospectively analyzed the clinical and laboratory data of 124 anti⁃MDA5+DM patients from the First Affiliated Hospital of Nanjing Medical University between March 2019 and September 2023.We identified independent risk factors associated with the development and mortality of RPILD with the Cox regression analysis,and determined the optimal cut⁃off values for predicting adverse outcomes with the receiver operating characteristic(ROC)curve analysis.Results:Among the 124 patients,36 patients(29.03%)developed RPILD,and 39 patients(31.45%)died during the follow⁃up period.The results of multivariate Cox regression analysis showed that the elevated NLR was an independent risk factor for RPILD development,while the elevated SII expression was independently associated with the increased mortality of RPILD.Based on the ROC curve analysis,NLR>6.12 was a predictor for RPILD,and SII>875.79 was associated with increased mortality risk of RPILD.Conclusion:Both NLR and SII are accessible,cost⁃effective,and reliable prognostic indicators for the prognosis of patients with anti⁃MDA5^(+)DM,providing a valuable guidance for clinical management and risk stratification of the disease. 展开更多
关键词 anti⁃melanoma differentiation⁃associated gene 5⁃positive dermatomyositis neutrophil⁃to⁃lymphocyte ratio rapidly pro⁃gressive interstitial lung disease systemic immune⁃inflammation index
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Early diagnosis and targeted intervention based on the pathogenesis of rapidly progressive osteoarthritis of the hip
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作者 Tadashi Yasuda 《World Journal of Orthopedics》 2025年第10期5-20,共16页
Early diagnosis of rapidly progressive osteoarthritis of the hip(RPOH)remains clinically challenging due to the lack of unified guidelines and standardized diagnostic criteria.Current diagnostic criteria(chondrolysis&... Early diagnosis of rapidly progressive osteoarthritis of the hip(RPOH)remains clinically challenging due to the lack of unified guidelines and standardized diagnostic criteria.Current diagnostic criteria(chondrolysis>2 mm/year)require follow-up for at least 12 months.This review characterizes two types of earlystage RPOH progression:Chondrolysis with or without subsequent femoral head destruction within 12 months of onset.Based on their association with early disease progression in RPOH,elevated serum matrix metalloproteinase-3 levels and spinopelvic malalignment may serve as predictive factors for subsequent bone destruction when only joint space narrowing is observed.This review also proposes potential mechanisms of pathogenesis and intervention strategies for RPOH at its initial stage.Cartilage matrix fragments generated by stress concentrations on the hip joint,resulting from spinopelvic malalignment,may trigger inflammatory pathways involving proinflammatory cytokines and inflammasome activation,ultimately leading to joint destruction in the initial phase of RPOH.Suppression of these early pathological events may prevent joint destruction caused by RPOH.However,further elucidation of the cellular and molecular pathways involved in rapid joint destruction is necessary to identify specific biomarkers for early diagnosis and to facilitate the development of targeted therapies in the initial phase of RPOH. 展开更多
关键词 rapidly progressive osteoarthritis Hip joint Classification Early diagnosis Early intervention Imaging Matrix metalloproteinase-3 Spinopelvic alignment PATHOPHYSIOLOGY
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IgA vasculitis in an adult diabetic male with rapidly progressive glomerulonephritis:A case study
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作者 Varsha Luthra Aprajita Garg +2 位作者 Anjali Yadav Tarun Chaudhary Monica Gupta 《Journal of Acute Disease》 2025年第5期1-4,共4页
Rationale:IgA vasculitis or Henoch-Schonlein purpura is an immune complex mediated small vessel vasculitis characterized by clinical triad of arthritis,palpable purpura and gastrointestinal symptoms.It is commonly see... Rationale:IgA vasculitis or Henoch-Schonlein purpura is an immune complex mediated small vessel vasculitis characterized by clinical triad of arthritis,palpable purpura and gastrointestinal symptoms.It is commonly seen in children below 10-year-old,though adults may be affected.Patient’s Concern:A 40-year-old man with type-2 diabetes mellitus presented with fever,melena,palpable purpuric rash and hematuria with acute kidney injury,associated with nephrotic range proteinuria.Skin biopsy revealed leukocytoclastic vasculitis and renal biopsy showed IgA deposits in the mesangium and capillary loops with fibro cellular crescents confirming the diagnosis of IgA vasculitis with crescentic rapidly progressive glomerulonephritis.Diagnosis:IgA vasculitis with rapidly progressive glomerulonephritis.Interventions:The patient was treated with pulse intravenous methylprednisolone 500 mg/day for 3 days with tapering doses of oral prednisolone and intravenous cyclophosphamide(0.5 gm/m^(2) body surface area)under the cover of intravenous antibiotics for diabetic foot ulcer.Outcomes:Patient improved gradually with return to baseline creatinine after 3 months of follow up.Lessons:Rapidly progressive glomerulonephritis is a rare manifestation of IgA vasculitis and warrants special care and early treatment.The incidence of rapidly progressive glomerulonephritis in IgA vasculitis is unknown.It carries a high risk of progression to chronic kidney disease and thus should be treated as soon as feasible after diagnosis. 展开更多
关键词 Henoch-Schonlein purpura IgA vasculitis Crescentic rapidly progressive glomerulonephritis Type-2 diabetes mellitus
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Microstructural Evolution of Rapidly Solidified Ni-Cu Alloys
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作者 QU Shuwei LI Zejun +4 位作者 WANG Hongfu TIAN Xiaoguang QIAN Zhike LI Ruiqin YAO Wei 《Journal of Wuhan University of Technology(Materials Science)》 2025年第6期1759-1765,共7页
This study systematically investigated the microstructural evolution of binary Ni-Cu alloys(Cu55Ni45,Cu60Ni40,and Ni65Cu35)under deep undercooling conditions.The controlled rapid solidification experiments combined wi... This study systematically investigated the microstructural evolution of binary Ni-Cu alloys(Cu55Ni45,Cu60Ni40,and Ni65Cu35)under deep undercooling conditions.The controlled rapid solidification experiments combined with optical microscopy and electron backscatter diffraction(EBSD)analysis demonstrate that increasing undercooling(ΔT)can induce a consistent sequence of microstructural transitions:coarse dendrites,fine equiaxed grains(first refinement),oriented fine dendrites,and fine equiaxed grains(second refinement).Two distinct grain refinement events are identified,with critical undercooling thresholds(ΔT)dependent on composition:increasing Cu content increases the critical undercoolingΔT*required for the second refinement(Cu55Ni45:227 K;Cu60Ni40:217 K;Ni65Cu35:200 K).The BCT(Bridgman Crystal Growth)model quantitatively elucidates this behavior,revealing a shift from solute-diffusion-dominated growth at low undercooling to thermally dominated diffusion at high undercooling(ΔT).Crucially,refined grains at high undercooling exhibit smaller sizes(10μm)and higher uniformity than those at low undercooling(20μm).These findings provide fundamental insights into non-equilibrium solidification mechanisms and establish a foundation for designing high-performance Ni-Cu alloys via deep undercooling processing. 展开更多
关键词 deep undercooling Ni-Cu alloys microstructural evolution grain refinement BCT model rapid solidification
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Design and implementation of an integrated and rapidly assembled infrared three-band optical system
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作者 Shuanglong Tan Yulin Wang +3 位作者 Guangwei Shi Shuaiwei Mu Xin Zhang Lin Ma 《Astronomical Techniques and Instruments》 2025年第2期88-99,共12页
Continuing advancement in astronomy,space exploration,and scientific detection,has increased demand for infrared multi-band detection systems.Traditional three-band optical systems,designed to simultaneously image at ... Continuing advancement in astronomy,space exploration,and scientific detection,has increased demand for infrared multi-band detection systems.Traditional three-band optical systems,designed to simultaneously image at infrared short-wave,mid-wave,and long-wave bands typically rely on dispersive elements,leading to bulky sizes,complex system architectures,low efficiency,and challenges in rapid assembly.To overcome these obstacles,in combination with the latest third-generation infrared detectors,we propose a design for a compact and lightweight three-band optical system,with infrared capabilities in all three required bands.The core of this approach is an integrated design philosophy that emphasizes the high steepness of mirror surfaces.This design achieves uniform correction and optimization of chromatic aberration and off-axis aberration across the spectral range.We introduce a novel integration of optical and mechanical elements to replace traditional assembly,reducing manufacturing and assembly errors,and degrees of freedom,associated with high-power optical elements.Confirming the effectiveness through a combination of simulations and experimental comparisons,the measured mid-wave full-field transfer function exceeds 0.405 at 17 lp/mm,satisfying the imaging requirements of the system.The optical system is lightweight and compact,with a total mass under 408 g and a compact volume of justΦ112 mm×117 mm.This serves as a valuable reference for the engineering application of high-performance,compact multi-band infrared composite detection systems for astronomy and space exploration. 展开更多
关键词 Three-band infrared INTEGRATED Rapid assembly Modulation Transfer Function(MTF)
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Optimized new Shengmai powder(优化新生脉散方) inhibits myocardial fibrosis in heart failure by regulating the rat sarcoma/rapidly accelerated fibrosarcoma/mitogen-activated protein kinase kinase/extracellular regulated protein kinases signaling pathway
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作者 ZHANG Zeyu JIA Zhuangzhuang +7 位作者 SONG Yuwei ZHANG Xuan WANG Ci WANG Shuai ZHANG Peipei REN Qiuan WANG Xianliang MAO Jingyuan 《Journal of Traditional Chinese Medicine》 SCIE CSCD 2024年第3期448-457,共10页
OBJECTIVE: Exploring the effect of Optimized New Shengmai powder(优化新生脉散方, ONSMP) on myocardial fibrosis in heart failure(HF) based on rat sarcoma(RAS)/rapidly accelerated fibrosarcoma(RAF)/mitogen-activated pro... OBJECTIVE: Exploring the effect of Optimized New Shengmai powder(优化新生脉散方, ONSMP) on myocardial fibrosis in heart failure(HF) based on rat sarcoma(RAS)/rapidly accelerated fibrosarcoma(RAF)/mitogen-activated protein kinase kinase(MEK)/extracellular regulated protein kinases(ERK) signaling pathway. METHODS: Randomized 70 Sprague-Dawley rats into sham(n = 10) and operation(n = 60) groups, then established the HF rat by ligating the left anterior descending branch of the coronary artery. We randomly divided the operation group rats into the model, ONSMP [including low(L), medium(M), and high(H) dose], and enalapril groups. After the 4-week drug intervention, echocardiography examines the cardiac function and calculates the ratios of the whole/left heart to the rat's body weight. Finally, we observed the degree of myocardial fibrosis by pathological sections, determined myocardium collagen(COL) Ⅰ and COL Ⅲ content by enzyme-linked immunosorbent assay, detected the m RNA levels of COL Ⅰ, COL Ⅲ, α-smooth muscle actin(α-SMA), and c-Fos proto-oncogene(c-Fos) by universal real-time, and detected the protein expression of p-RAS, p-RAF, p-MEK1/2, p-ERK1/2, p-ETS-like-1 transcription factor(p-ELK1), p-c-Fos, α-SMA, COL Ⅰ, and COL Ⅲ by Western blot. RESULTS: ONSMP can effectively improve HF rat's cardiac function, decrease cardiac organ coefficient, COL volume fraction, and COL Ⅰ/Ⅲ content, down-regulate the m RNA of COL Ⅰ/Ⅲ, α-SMA and c-Fos, and the protein of p-RAS, p-RAF, p-MEK1/2, p-ERK1/2, p-ELK1, c-Fos, COL Ⅰ/Ⅲ, and α-SMA. CONCLUSIONS: ONSMP can effectively reduce myocardial fibrosis in HF rats, and the mechanism may be related to the inhibition of the RAS/RAF/MEK/ERK signaling pathway. 展开更多
关键词 myocardial fibrosis heart failure SARCOMA rapidly accelerated fibrosarcoma mitogen-activated protein kinases extracellular regulated protein kinases optimized new Shengmai powder
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Effect of dietary with Zhibai dihuang pills and gonadotropinreleasing-hormone-analogue on girls with precocious and rapidly progressive puberty
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作者 Xue-Mei Wang Wei Li +2 位作者 Liu-Qing Yang Rui Luo Chen-Chen Zhang 《World Journal of Clinical Cases》 SCIE 2024年第24期5534-5541,共8页
BACKGROUND At present,the clinical mechanisms underlying precocious puberty remain unclear,making effective intervention for children experiencing this condition and rapidly progressive puberty essential.AIM To explor... BACKGROUND At present,the clinical mechanisms underlying precocious puberty remain unclear,making effective intervention for children experiencing this condition and rapidly progressive puberty essential.AIM To explore the effects of Zhibai dihuang pills and gonadotropin-releasing hormone analogue(GnRHa)on growth and ovarian function in girls with precocious puberty.METHODS The clinical data of 84 adolescent girls with precocious puberty and rapidly progressive puberty from February 2017 to August 2023 were retrospectively analyzed.Girls were divided into a control group and an observation group,with 42 cases in each group.The control group received diet intervention combined with GnRHa treatment,while the observation group received diet intervention combined with Zhibai dihuang pills+GnRHa treatment.Outcomes such as clinical efficacy,growth indicators,ovarian function,and adverse reactions were compared between the two groups.RESULTS The observation group showed superior clinical efficacy compared to the control group(P<0.05).Prior to the intervention,no significant differences were found in growth or ovarian function between the groups(P>0.05).Post-intervention,the observation group exhibited significantly lower rates in growth,height,and bone age,along with reduced levels of progesterone,testosterone,estradiol,prolactin,luteinizing hormone,and follicle-stimulating hormone compared to the control group(P<0.05).The incidence of adverse reactions was similar across both groups(P>0.05).CONCLUSION Combining Zhibai dihuang pills with GnRHa and dietary intervention effectively improves growth,enhances ovarian function,and minimizes adverse reactions in adolescent girls with precocious and rapidly progressive puberty. 展开更多
关键词 Zhibai dihuang pills Gonadotropin-releasing hormone analogue Dietary intervention Precocious puberty rapidly progressive puberty Ovarian function
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Microstructure dependence of electrochemical corrosion resistance for rapidly solidified Ti_(50)Al_(48)Mo_(2)alloy
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作者 Chonghao Sun Ruilin Xiao +2 位作者 Kelun Liu Ying Ruan Bingbo Wei 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第18期58-68,共11页
The rapid solidification of undercooled liquid Ti_(50)Al_(48)Mo_(2)alloy was achieved by the electromagnetic lev-itation(EML)technique.At small and medium undercoolings,primary(βTi)dendrite reacted with sur-rounding ... The rapid solidification of undercooled liquid Ti_(50)Al_(48)Mo_(2)alloy was achieved by the electromagnetic lev-itation(EML)technique.At small and medium undercoolings,primary(βTi)dendrite reacted with sur-rounding liquid to drive a peritectic transformation into the(αTi)phase.The solutal Mo and Al segrega-tions were located within the dendrite center and the grain boundary during peritectic transformation,consequently B2 phase in the dendrite center andγphase at the grain boundary formed.Once under-cooling exceeded 253 K,the peritectic transformation was completely inhibited,and the formation of the B2 phase andγphase was completely suppressed.The ultrafine eutectoid structure was formed and a complete solute trapping effect was realized.Homogeneous solute distribution facilitated the forma-tion of thicker passivation film with lower defect density and higher film resistance on the alloy surface.Moreover,this weakened micro-galvanic effect reduced the susceptibility to pitting corrosion,and conse-quently the corrosion resistance of the alloy was improved. 展开更多
关键词 Ti-Al based alloys Electromagnetic levitation technique UNDERCOOLING Rapid solidification Passivation film
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Quantitative imaging of dynamic myocardial blood flow using dual‐head rapidly rotating gantry single‐photon emission computed tomography to enhance coronary artery disease diagnosis
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作者 Yongli Bai Bingyue Bai +4 位作者 Gang Miao Wenzhi Wang Longmei Wang Dan Ma Wenjing Shi 《iRADIOLOGY》 2024年第3期305-317,共13页
Background:This study aimed to evaluate the performance of myocardial blood flow(MBF)and myocardial flow reserve(MFR)for diagnosing coronary artery disease(CAD)using dynamic single‐photon emission computed to-mograph... Background:This study aimed to evaluate the performance of myocardial blood flow(MBF)and myocardial flow reserve(MFR)for diagnosing coronary artery disease(CAD)using dynamic single‐photon emission computed to-mography/computed tomography(SPECT/CT)with a dual‐head rapidly rotating gantry(RRG)and to compare this method with conventional myocardial perfusion imaging(MPI),which can be obtained in a one‐stop manner.Methods:A total of 93 patients with suspected or confirmed CAD who un-derwent RRG SPECT/CT were retrospectively enrolled.They underwent invasive coronary angiography(ICA)and conventional MPI within 3 weeks.Based on the ICA results,the performance of MBF quantitative and semi‐quantitative parameters were compared at patient and vessel levels using≥50%and≥75%stenosis as the criteria for CAD diagnosis.Receiver operating characteristic(ROC)curve was used to evaluate the diagnostic efficacy of two types of parameters.Results:For patient‐level analysis,the area under ROC curves(AUCs)for stress MBF(sMBF),MFR,summed stress score(SSS),and summed different score(SDS)were 0.971,0.939,0.612,and 0.546,respectively,for≥50%stenosis as positive,and were 0.983,0.932,0.735,and 0.509,respectively,for≥75%stenosis as positive criteria.For vessel‐level analysis,the AUCs of sMBF,MFR,SSS,and SDS were 0.981,0.933,0.636,and 0.560,respectively,for≥50%stenosis as positive and were 0.984,0.933,0.767,and 0.583,respectively,for≥75%stenosis as positive criteria.Conclusions:Compared with semi‐quantitative parameters of conventional MPI,MBF quantitative parameters of dual‐head RRG SPECT had higher diagnostic performance for CAD. 展开更多
关键词 CAD dual‐head rapid rotating GANTRY (RRG) SPECT MULTIVESSEL disease MYOCARDIAL blood FLOW MYOCARDIAL FLOW reserve MYOCARDIAL ischemia quantitative
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Formulation Study for Rotundine Rapidly Disintegrating Tablet
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作者 王小琼 柯学 +1 位作者 平其能 许伯慧 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第2期100-104,共5页
Aim The aim of the present study was to prepare tablets which can rapidlydisintegrate in saliva, containing active ingredient in high dose (37.5% W/W). Methods Rapidlydisintegrating tablets containing rotundine were p... Aim The aim of the present study was to prepare tablets which can rapidlydisintegrate in saliva, containing active ingredient in high dose (37.5% W/W). Methods Rapidlydisintegrating tablets containing rotundine were prepared by direct compression, wet granulation andmoulding, respectively . Different disintegrants and excipients were decided by single factor test.The typical disintegration time measurement and a new method of wetting time measuring wereintroduced for assessing rapidly disintegrating tablets. Results The tablets (80 mg) prepared bydirect compression have the crushing strength of 4.0 kg ?mm^(-2) and rapidly disintegratewithin 15 s in the saliva of healthy volunteers; the tablets prepared by wet granulation also havesufficient strength, a little longer but acceptable disintegration time (within 25 s in saliva) ;and the tablets obtained by moulding show disintegration within 40 s in saliva but low strength (2kg·mm^(-2)) . Disintegration time profiles of tablets are similar to those of wetting time, and thedisintegration and wetting times in vitro are similar to the disintegration time in vivo, thelatter having higher correlation with that in oral cavity. Conclusion The rapidly disintegratingtablets can be prepared by using these three techniques and excipients. Both in vitro disintegrationtime and wetting time are necessary indexes for judgment of in vitro disintegration profile. 展开更多
关键词 ROTUNDINE rapidly disintegrating tablets disintegration time wetting time
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Comparison of dendrite and dispersive structure in rapidly solidified Cu-Co immiscible alloy with different heat flow modes 被引量:3
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作者 李圣 刘峰 杨伟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第1期227-233,共7页
Rapid solidification of Cu-Co immiscible alloy was investigated by glass-fluxing, spray casting and melt-spinning techniques. Both the transition from dendrite to dispersive structure and corresponding scale evolution... Rapid solidification of Cu-Co immiscible alloy was investigated by glass-fluxing, spray casting and melt-spinning techniques. Both the transition from dendrite to dispersive structure and corresponding scale evolution were revealed and further elucidated in terms of the heat flow mode, nucleation and growth processes under different solidification conditions. With the increase of undercooling, columnar dendrite is replaced by dispersive structure due to the immiscible effect. In contrast, equiaxed dendrite forms in spray cast alloy due to multiple nucleation events and becomes thinner for the case of higher cooling rate. Ascribed to the enhanced non-equilibrium effect and insufficient period for collision and coagulation processes between separated droplets, fine globular dispersion appears upon the diameter of spray casting reaching 4 mm. As for the melt-spun ribbon with the highest cooling rate, a single-phase solid solution microstructure with refined grain of cellular morphology can be obtained, which is attributed to the suppression of liquid phase separation by instant solidification. 展开更多
关键词 rapid solidification immiscible alloy microstructure NUCLEATION growth
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The usefulness and significance of assessing rapidly progressive spermatozoa 被引量:16
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作者 Lars Bjorndahl 《Asian Journal of Andrology》 SCIE CAS CSCD 2010年第1期33-35,共3页
It is possible and clinically relevant to distinguish between slow and rapid progressive spermatozoa in basic semen analysis. This is discussed in light of the different purposes of semen analysis for the subfertile c... It is possible and clinically relevant to distinguish between slow and rapid progressive spermatozoa in basic semen analysis. This is discussed in light of the different purposes of semen analysis for the subfertile couple and the male patient. The two groups of progressive spermatozoa should be distinguished to help ensure that pertinent information available in the semen sample is not neglected. 展开更多
关键词 male factor infertility manual sperm motility assessment quality control rapidly progressive spermatozoa referencevalues semen analysis staff training
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Effect of cooling rates on clustering towards icosahedra in rapidly solidified Cu_(56)Zr_(44) alloy 被引量:1
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作者 胡艳军 文大东 +2 位作者 蒋元祺 邓永和 彭平 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第2期533-543,共11页
The rapid solidification processes of liquid Cu56Zr44 alloys at different cooling rates (γ) were simulated by a molecular dynamics (MD) method. In order to assess the influence of cooling rate on the clustering t... The rapid solidification processes of liquid Cu56Zr44 alloys at different cooling rates (γ) were simulated by a molecular dynamics (MD) method. In order to assess the influence of cooling rate on the clustering tendency and degree towards icosahedrons, a ten-indices' cluster-type index method was suggested to characterize the local atomic structures in the super-cooled liquid and the rapidly solidified solid. And their clustering and ordering degrees as well as the packing density of ieosahedral clusters were also evaluated by an icosahedral clustering degree (fI), the chemical order parameter (ηαβ) and densification coefficients (D0, DI and DIS), respectively. Results show that the main local atomic configurations in Cu56Zr44 alloy system are Z12 clusters centered by Cu, and most of which are (12 0 12 0 0 0 0 0 0 0) standard icosahedra and (12 0 8 0 0 0 2 2 0 0) as well as (12 2 8 2 0 0 0 0 0 0) defective icosahedra. Below glass transition temperature (Tg), these icosahedral clusters will be coalesced to various icosahedral medium-range orders (IMROs) by IS linkages, namely, icosahedral bond, and their number N, size n, order parameter ηαβ as well as spatial distributions vary with y. As the cooling rate exceeds the critical value (γc) at which a glassy transition can take place, a lower cooling rate, e.g., γ1=10^1K/ns, is demonstrated to be favorable to uplift the number of icosahedra and enlarge the size of IMROs compared with the higher cooling rates, e.g., γ5=10^5 K/ns, and their packing density and clustering degree towards icosahedra in the rapidly solidified solid can also benefit from the slow cooling process. 展开更多
关键词 rapid solidification Cu-Zr alloy cooling rate CLUSTERING ICOSAHEDRON
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Microstructure and Properties of Cu-Cr-Zr Alloy after Rapidly Solidified Aging and Solid Solution Aging 被引量:14
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作者 Ping LIU Juanhua SU +1 位作者 Qiming DONG Hejun LI 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第4期475-478,共4页
The structure and properties of Cu-Cr-Zr alloy were studied after rapidly solidified aging and solid solution aging.At the early stage of aging (500℃ for 15 rain), the hardness and the conductivity of the alloy rap... The structure and properties of Cu-Cr-Zr alloy were studied after rapidly solidified aging and solid solution aging.At the early stage of aging (500℃ for 15 rain), the hardness and the conductivity of the alloy rapidly solidified are 143 HV and 72% IACS, respectively. Under the same aging condition, the hardness and electrical conductivity of the alloy solid solution treated can reach 86 HV and 47% IACS, respectively. The microstructure was analyzed, and the grain size after rapid solidification is much smaller than that after solid solution treatment. By rapidly solidified aging the fine precipitates distribute inside the grains and along the grain boundary, while by solid solution aging there are large Cr particles along the grain boundary. 展开更多
关键词 Cu-Cr-Zr alloy PROPERTIES Solid solution aging rapidly solidified aging
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Microstructure and thermal stability behavior of a rapidly solidified Al-Ti-Fe-Cr alloy 被引量:3
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作者 CHEN Yiqing, CAO Qingping, and SU YongSchool of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China 《Rare Metals》 SCIE EI CAS CSCD 2002年第3期207-212,共6页
A rapidly solidified Al-2.5Ti-2.5Fe-2.5Cr (mass fraction in percent) alloywas prepared by melt spinning. As-quenched and as-annealed microstructures were studied by X-raydiffractometry (XRD), transmission electron mic... A rapidly solidified Al-2.5Ti-2.5Fe-2.5Cr (mass fraction in percent) alloywas prepared by melt spinning. As-quenched and as-annealed microstructures were studied by X-raydiffractometry (XRD), transmission electron microscopy (TEM), high-resolution transmission electronmicroscopy (HREM) and energy dispersive spectrum (EDS) analysis. The microhardness of the alloy atdifferent annealing temperatures was measured. The results obtained indicate that the microhardnessof the rapidly solidified Al-2.5Ti-2.5Fe-2.5Cr alloy does not vary with different annealingtemperatures. The as-quenched microstructure of the alloy includes two kinds of dispersed primaryphases: Al_3Ti and Al_(13)(Cr, Fe)_2. After annealing at 400 deg C for 10 h, the stable phaseAl_(13)Fe_4 appears in the microstructure. 展开更多
关键词 rapidly solidified Al-Ti-Fe-Cr alloy MICROHARDNESS as-quenchedmicrostructure as-annealed microstructure
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Effect of heat treatment on the microstructure and micromechanical properties of the rapidly solidified Mg61.7Zn34Gd4.3 alloy containing icosahedral phase 被引量:2
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作者 Wen-bo Luo Zhi-yong Xue Wei-min Mao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第7期869-877,共9页
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
关键词 magnesium ALLOY ICOSAHEDRAL phase rapidly SOLIDIFICATION NANOINDENTATION MICROMECHANICAL properties
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Effects of Additional Elements on Microstructure and Precipitation Behaviour in Rapidly Solidified Al-Ti Base Alloys 被引量:3
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作者 Won-Wook Park Chul-Jin Choi and Bong-Sun You (Dept. of Materials Processing, Korea Institute of Machinery and Metals, 66 Sangnam-Dong,Changwon, Kyungnam, Korea 641-010)(To whom correspondence should be addressed) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1996年第3期195-198,共4页
Rapidly solidified Al-Ti base alloys were prepared by melt spinning at the cooling rate about 107 K/s. The melt-spun ribbons were used to observe the dricrostructures after heat treatment.In the supersaturated Al-Tl-S... Rapidly solidified Al-Ti base alloys were prepared by melt spinning at the cooling rate about 107 K/s. The melt-spun ribbons were used to observe the dricrostructures after heat treatment.In the supersaturated Al-Tl-Si alloy, age hardening occurred after 1 h anneal in the temperature range of 4000~500℃, which seems to be attributed to the precipitation of metastable Ll2- (Al,Si)3Ti phase. However. the microhardness was relatively low because of the low v/o and the insufflcient stability of precipitates. Thus. Cr was added to Al-Ti-Si alloys in order to stabilize the microstructures and to increase the v/o of precipitate5. As a result. the alIoys containing Cr were evaluated to possess the improved properties at the service temperature. 展开更多
关键词 Ti BASE Al Effects of Additional Elements on Microstructure and Precipitation Behaviour in rapidly Solidified Al-Ti Base Alloys
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Rugate filters prepared by rapidly alternating deposition 被引量:1
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作者 张俊超 方明 +2 位作者 邵宇川 晋云霞 贺洪波 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期258-261,共4页
A methodology for the fabrication of composite (Nb205)l-x(SiO2)~ thin-film rugate filters by using pulsed direct current magnetron sputtering is presented. The two materials are mixed using rapidly alternating dep... A methodology for the fabrication of composite (Nb205)l-x(SiO2)~ thin-film rugate filters by using pulsed direct current magnetron sputtering is presented. The two materials are mixed using rapidly alternating deposition technol- ogy. The optical properties of the composite films varying with the composition of the material are studied in detail, Refractive indices between 1.50 and 2.14 can be realized in our coating system. Two designed rugate filters with a re- flection band at the wavelength of 532 nm are fabricated using an automatic deposition process. The microstructure of the rugate filter is investigated by using scanning electron microscopy. The calculated and the measured transmittance spectra axe in good agreement with each other, The causes of the slight differences between them are also analysed. 展开更多
关键词 rapidly alternating deposition rugate filter magnetron sputtering mixed oxides
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Positron Annihilation Study on the Microstructural Stability in Rapidly Solidified Al_(92.3)Fe_(4.3)V_(0.7)Si_(1.7)Mm_(1.0) Alloy 被引量:1
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作者 Wei JIA Meikuang Tseng and Jianqiang WANG(Dept. of Material Science, Northeastern University Shenyang 110006, China)Liangyue XIONG and Yelong CHU(International Ceoter for Materials Physics, Institute of Metal Research, Chinese Academy of Sciences,Shenyan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1998年第2期179-181,共3页
Rapidly solidified Al92.3Fe4.3V0.7Si1.7Mm1.0 alloy has been studied by positron lifetime spectroscopy and the variations on the intedecial defects with the annealing temperature were revealed by an analysis of the lif... Rapidly solidified Al92.3Fe4.3V0.7Si1.7Mm1.0 alloy has been studied by positron lifetime spectroscopy and the variations on the intedecial defects with the annealing temperature were revealed by an analysis of the lifetime results. The intedece characteristics derived from the positron-lifetime results could be used to give a satisfactory interpretation of the dependence of mechanical properties on the annealing temperature 展开更多
关键词 FE Positron Annihilation Study on the Microstructural Stability in rapidly Solidified Al MM SI
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TEM microstructure of rapidly solidified Mg-6Zn-1Y-1Ce alloy
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作者 杨文朋 郭学锋 卢正欣 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期786-792,共7页
Rapidly solidified(RS) Mg-6Zn-1Y-1Ce ribbons were prepared by single roller melt-spinning technique.Transmission electron microscopy and energy dispersive X-ray spectroscopy were employed to characterize the microst... Rapidly solidified(RS) Mg-6Zn-1Y-1Ce ribbons were prepared by single roller melt-spinning technique.Transmission electron microscopy and energy dispersive X-ray spectroscopy were employed to characterize the microstructure of RS ribbons.The results show that there is high density of particles distributed within grains and at grain boundaries in the region near wheel side.The particle density is decreased in the middle region and free surface region.The alloy is predominantly composed of supersaturated--Mg solid solution,T phase and W phase;meanwhile,a few icosahedral quasicrystalline and Mg4Zn7 particles are also observed.The T phase is confirmed having a body-centered orthorhombic structure that is transformed from the body-centered tetragonal structure Mg12Ce phase due to the partial substitution of Mg atoms by Zn. 展开更多
关键词 Mg-6Zn-1Y-1Ce alloy rapid solidification T phase icosahedral quasicrystalline Mg4Zn7 phase W phase
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