Twin

双床
  • 文章类型: Journal Article
    背景:虽然环境空气污染与单胎胎儿的生长有关,由于该领域的研究有限,其在双胞胎之间的相关性尚不明确。
    方法:在上海市第九人民医院生殖医学中心(上海,中国)2007年至2021年。其他与出生体重相关的结果包括巨大儿,低出生体重,出生体重很低,小于胎龄(SGA)。使用线性混合效应模型和随机效应逻辑回归模型分析了PM2.5暴露与出生体重的关系。结合分布式滞后模型(DLM)来估计时变关联。
    结果:研究结果表明,整个怀孕期间PM2.5暴露的四分位数间距(IQR)增加(18μg/m3)与显着增加有关(57.06g,双胞胎总出生体重的95%置信区间[CI]:30.91,83.22)。在较大的胎儿(34.93g,95%CI:21.13,48.72)与较小的胎儿(21.77g,95%CI:6.94,36.60)双胎妊娠。此外,整个怀孕期间PM2.5暴露的IQR增加与LGA风险增加34%相关(95%CI:11%,63%)。此外,PM2.5的特定化学成分,如硫酸盐(SO42-),表现出与PM2.5总质量相当的效果估计。
    结论:总体而言,研究结果表明,暴露于PM2.5及其特定成分与双胞胎胎儿过度生长有关。
    BACKGROUND: While ambient air pollution has been associated with fetal growth in singletons, its correlation among twins is not well-established due to limited research in this area.
    METHODS: The effects of exposure to PM2.5 particulate matter and its main components during pregnancy on birth weight and the incidence of large for gestational age (LGA) were investigated in 6177 twins born after in vitro fertilization at the Center for Reproductive Medicine of Shanghai Ninth People\'s Hospital (Shanghai, China) between 2007 and 2021. Other birth weight-related outcomes included macrosomia, low birth weight, very low birth weight, and small for gestational age (SGA). The associations of PM2.5 exposure with birth weight outcomes were analyzed using linear mixed-effect models and random-effect logistic regression models. Distributed lag models were incorporated to estimate the time-varying associations.
    RESULTS: The findings revealed that an interquartile range (IQR) increase (18 μg/m3) in PM2.5 exposure over the entire pregnancy was associated with a significant increase (57.06 g, 95 % confidence interval [CI]: 30.91, 83.22) in the total birth weight of twins. The effect was more pronounced in larger fetuses (34.93 g, 95 % CI: 21.13, 48.72) compared to smaller fetuses (21.77 g, 95 % CI: 6.94, 36.60) within twin pregnancies. Additionally, an IQR increase in PM2.5 exposure over the entire pregnancy was associated with a 34 % increase in the risk of LGA (95 % CI: 11 %, 63 %). Furthermore, specific chemical components of PM2.5, such as sulfate (SO42-), exhibited effect estimates comparable to the PM2.5 total mass.
    CONCLUSIONS: Overall, the findings indicate that exposures to PM2.5 and its specific components are associated with fetal overgrowth in twins.
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  • 文章类型: Case Reports
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  • 文章类型: Journal Article
    背景:淀粉样蛋白级联假说预测淀粉样蛋白-β(Aβ)聚集驱动tau缠结的积累。我们测试了关于Aβ40和Aβ42与总Tau(t-Tau)血浆生物标志物之间因果关系方向的竞争性因果和非因果假设。
    方法:血浆Aβ40,Aβ42,t-Tau,使用Simoa免疫测定法对1,035名男性(平均67.0岁)进行了神经丝轻链(NFL)测量。遗传信息孪生模型测试了Aβs和t-Tau之间因果关系的方向。
    结果:没有观察到Aβ40或Aβ42直接导致t-Tau变化的明确证据;替代因果假设也很好地拟合了数据。相比之下,探索性分析表明Aβ生物标志物对NFL的因果影响。分别,t-Tau和NFL之间存在相互因果关系。
    结论:血浆Aβ40或Aβ42似乎对t-Tau没有直接的因果关系。相比之下,Aβ聚集可能会对60多岁的认知未受损男性的NFL产生因果关系。
    BACKGROUND: The amyloid cascade hypothesis predicts that amyloid-beta (Aβ) aggregation drives tau tangle accumulation. We tested competing causal and non-causal hypotheses regarding the direction of causation between Aβ40 and Aβ42 and total Tau (t-Tau) plasma biomarkers.
    METHODS: Plasma Aβ40, Aβ42, t-Tau, and neurofilament light chain (NFL) were measured in 1,035 men (mean = 67.0 years) using Simoa immunoassays. Genetically informative twin modeling tested the direction of causation between Aβs and t-Tau.
    RESULTS: No clear evidence that Aβ40 or Aβ42 directly causes changes in t-Tau was observed; the alternative causal hypotheses also fit the data well. In contrast, exploratory analyses suggested a causal impact of the Aβ biomarkers on NFL. Separately, reciprocal causation was observed between t-Tau and NFL.
    CONCLUSIONS: Plasma Aβ40 or Aβ42 do not appear to have a direct causal impact on t-Tau. In contrast, Aβ aggregation may causally impact NFL in cognitively unimpaired men in their late 60s.
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  • 文章类型: Journal Article
    背景:这项研究调查了孕妇在第一次接触颗粒物(PM10)和二氧化氮(NO2)之间的关系,出生时双胞胎的第二和第三个三个月和胎盘重量以及出生体重/胎盘重量(BW/PW)比率。
    方法:使用来自东佛兰德斯前瞻性双胞胎调查的3340对双胞胎的横截面数据。通过时空插值估算空气污染物暴露。对具有单独胎盘的双胞胎进行了随机截距的单变量和多变量混合模型分析,以考虑新生儿的亲缘关系。用线性和逻辑回归研究了具有一个胎盘质量的双胎对。
    结果:在妊娠晚期,PM10或NO2胎盘重量每增加10μm/m3,分别减少-19.7g(95%-C.I.-35.1;-4.3)和-17.7g(95%-C.I.-30.4;-0.5),中度至晚期早产双胞胎有单独的胎盘。因此,BW/PW比率随着空气污染暴露的增加而增加。妊娠最后一周的PM10暴露与“小于胎龄胎盘”(胎盘重量<10百分位数)的比值比(OR)较高,为1.20(95%-C.I.1.00;1.44)。相反,孕早期空气污染物暴露与较低的OR值相关,分别为0.55(95%-C.I.0.35;0.88)和0.60(95%-C.I.0.42;0.84).
    结论:PM10和NO2对胎盘重量的关联是妊娠特异性的,有一个胎盘的双胞胎与两个胎盘的双胞胎不同,在中度至晚期早产双胞胎中最明显。需要进行纵向研究,以更好地了解不同孕期空气污染物暴露与胎盘重量演变之间的关系。
    This study investigates the association between maternal exposure to particulate matter (PM10) and nitric dioxide (NO2) during the first, second and third trimester and placental weight and birth weight/placental weight (BW/PW) ratio in twins at birth.
    Cross-sectional data of 3340 twins from the East Flanders Prospective Twin Survey was used. Air pollutant exposure was estimated via spatial temporal interpolation. Univariable and multivariable mixed model analyses with a random intercept to account for the relatedness of newborns were conducted for twins with separate placentas. Twin pairs with one placental mass were studied with linear and logistic regression.
    In the third trimester, for each 10 μm/m3 increase in PM10 or NO2 placental weight decreased -19.7 g (95%-C.I. -35.1; -4.3) and -17.7 g (95%-C.I. -30.4; -0.5) respectively, in moderate to late preterm twins with separate placentas. Consequently, BW/PW ratio increased with higher air pollution exposure. PM10 exposure in the last week of pregnancy was associated with a higher odds ratio (OR) of 1.20 (95%-C.I. 1.00; 1.44) for a \"small for gestational age placenta\" (placental weight <10th percentile). Conversely, first trimester air pollutant exposure was associated with lower ORs of 0.55 (95%-C.I. 0.35; 0.88) and 0.60 (95%-C.I. 0.42; 0.84).
    The association of PM10 and NO2 on placental weight is trimester-specific, differs for twins with one versus two placentas and is most pronounced in moderate to late preterm twins. Longitudinal studies are needed to better understand the relationship between air pollutant exposure and placental weight evolution across different trimesters.
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  • 文章类型: Journal Article
    背景:这项回顾性研究调查了以下假设:双胎妊娠中的母体血红蛋白(Hb)水平在孕早期和中期之间下降,并且较高的下降与出生时胎龄和出生体重(BW)较高相关。
    方法:研究人群被定义为双胎妊娠的孕妇,表型正常的新生儿,妊娠24+0周后,2009年10月至2021年9月在伦敦内部产科。母体Hb和平均红细胞体积(MCV),在≤14+0孕周(Hb1)和再次在20+0-30+0孕周(Hb2)记录从医院的围产期数据库。MCV被用作缺铁性贫血的可能指标。血红蛋白下降的关联,定义为[Hb1(针对胎龄进行调整)-Hb2],和MCV值与出生时的胎龄,双胞胎的BW和小于胎龄(SGA)新生儿的分娩,定义为BW<妊娠的第10百分位数,进行了评估。
    结果:纳入923例双胎妊娠孕妇。产妇Hb1与任何测量结果无关。然而,较低的Hb2和较大的Hb下降与出生时较高的胎龄有关(p<0.001),双胞胎1和2的BW更大(两者均p<0.001),并且分娩一个或两个SGA新生儿的发生率降低(两者均p<0.001)。MCV值与这些结果没有显著相关性。
    结论:这项研究表明,在双胎妊娠中,从孕早期到孕中期,孕妇血红蛋白下降幅度较大与出生时的胎龄较高和出生时的体重较大有关.该变化可以表示更大的等离子体体积膨胀。
    BACKGROUND: This retrospective study investigated the hypothesis that maternal hemoglobin (Hb) levels in twin pregnancy fall between the first and second trimesters and that higher falls are associated with higher gestational age at birth and higher birthweight (BW).
    METHODS: The study population was defined as pregnant women with twin pregnancies delivering two live, phenotypically normal neonates, after 24+0 weeks of gestation, between October 2009 and September 2021 at an inner London maternity unit. Maternal Hb and mean corpuscular volume (MCV), at ≤14+0 weeks of gestation (Hb1) and again at 20+0-30+0 weeks gestation (Hb2) were recorded from the Hospital\'s perinatal database. MCV was used as a possible indicator of iron deficiency anemia. The association of Hb drop, defined as [Hb1(adjusted for gestational age) - Hb2], and MCV values with gestational age at birth, BW of both twins and delivery of small for gestational age (SGA) neonates, defined as BW <10th percentile for gestation, was evaluated.
    RESULTS: 923 pregnant women with twin pregnancies were included. Maternal Hb1 did not correlate with any outcomes measured. However, a lower Hb2 and a larger Hb drop was associated with a higher gestational age at birth (p < 0.001), a larger BW of twin 1 and 2 (p < 0.001 for both) and a reduction in the incidence of delivering one or two SGA neonates (p < 0.001 for both). MCV values did not correlate significantly with these outcomes.
    CONCLUSIONS: This study showed that in twin pregnancy, a larger maternal Hb drop from the first to the second trimester is associated with a higher gestational age at birth and a larger BW. This change may represent a larger plasma volume expansion.
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  • 文章类型: Journal Article
    背景:这项研究调查了认知功能与中年尖端的59个可改变和内在因素之间的关系。
    方法:我们分析了来自科罗拉多州收养/双胞胎终生行为发展和认知衰老研究的1221名参与者的数据(CATSLife;Mage=33.20,%女性=52.74)。我们使用正则化回归和共生对照模型评估了59个因素对认知功能的影响,控制早期认知功能和灰质体积。
    结果:确定了八个稳健因素,包括教育程度,认知复杂性,生活的目的,和吸烟状况。报告认知复杂性和生活目标水平较高的双胞胎比他们的双胞胎表现出更好的认知表现,而吸烟则呈负相关。使用元分析得出的效应大小阈值,我们还发现,与他们的cotwin相比,经历更多财务困难的双胞胎往往表现不佳。
    结论:研究结果强调了认知功能与生活方式/心理因素之间的早期中年联系。超越先前的认知表现,大脑状态,遗传和家族混杂因素。我们的研究结果进一步强调了成年作为针对生活方式和社会心理因素的痴呆症预防干预措施的关键窗口的潜力。
    齿轮复杂度(+),生活目的(+)与中年早期认知相关。吸烟(-)也与中年早期的认知有关。结果是对遗传和环境混淆的一致控制。EA与认知之间的关联可能主要是遗传和家族性混淆。
    BACKGROUND: This study investigates the relationship between cognitive functioning and 59 modifiable and intrinsic factors at the cusp of midlife.
    METHODS: We analyzed data from 1221 participants in the Colorado Adoption/Twin Study of Lifespan behavioral development and cognitive aging (CATSLife; Mage = 33.20, %Female = 52.74). We assessed the impact of 59 factors on cognitive functioning using regularized regression and co-twin control models, controlling for earlier-life cognitive functioning and gray matter volume.
    RESULTS: Eight robust factors were identified, including education attainment, cognitive complexity, purpose-in-life, and smoking status. Twins reporting higher levels of cognitive complexity and purpose-in-life showed better cognitive performance than their cotwin, while smoking was negatively associated. Using meta-analytically derived effect size threshold, we additionally identified that twins experiencing more financial difficulty tend to perform less well compared with their cotwin.
    CONCLUSIONS: The findings highlight the early midlife link between cognitive functioning and lifestyle/psychological factors, beyond prior cognitive performance, brain status, genetic and familial confounders. Our results further highlight the potential of established adulthood as a crucial window for dementia prevention interventions targeting lifestyle and psychosocial factors.
    UNASSIGNED: Cog complexity(+), purpose-in-life(+) were associated with cognition in early midlife.Smoking(-) was also associated with cognition in early midlife.Results were consistent controlling for genetic and environmental confounds.Association between EA and cognition might be mostly genetic and familial confounded.
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  • 文章类型: Journal Article
    目的:评估不同医学辅助生殖策略(MAR)的相对影响,即一线治疗(有或没有宫腔内人工授精的卵巢刺激)和体外受精(IVF)程序(常规IVF或卵胞浆内单精子注射),多胞胎的风险。
    方法:我们利用伦巴第大区的医疗保健利用数据库来确定2007年至2022年期间MAR的出生。我们收集了有关多胎分娩总数的数据,并通过将多胎分娩数除以分娩总数来计算患病率。为了研究MAR后多胎分娩比例的时间趋势,对不同类型的技术和产妇年龄阶层分别采用线性回归模型.
    结果:纳入了MAR后的30,900例分娩;4485例(14.5%)一线治疗和26,415例(85.5%)IVF技术。总的来说,确定了4823例(15.6%)多胎。研究期间多胎分娩的频率从2007年的22.0%下降到2022年的8.7%(p<0.01)。一线治疗的多胎分娩稳定,从2007-2008年的13.5%到2021-2022年的12.0%(p=0.29)。IVF手术的多胎分娩率从2007-2008年的23.8%下降到2021-2022年的8.4%(p<0.01)。对产妇年龄(即<35岁和≥35岁)进行分层,趋势保持一致。
    结论:多胎分娩的减少受到IVF策略和程序变化的影响。自2009年以来,这种下降一直是渐进但稳定的,当时意大利废除了限制胚胎冷冻的法律。相比之下,一线治疗导致的多胎分娩比例随着时间的推移保持不变.尽管下降,来自MAR的多胎分娩仍然比来自自然妊娠的多胎分娩高出约一个数量级.
    OBJECTIVE: To evaluate the relative impact of different strategies of medically assisted reproduction (MAR), i.e. first line treatment (ovarian stimulation with or without intrauterine insemination) and in vitro fertilization (IVF) procedures (conventional IVF or intracytoplasmic sperm injection), on the risk of multiple births.
    METHODS: We utilized the health care utilization databases of the Lombardy region to identify births resulting from MAR between 2007 and 2022. We gathered data on the total number of multiple births and calculated the prevalence rate by dividing the number of multiples by the total number of births. To examine the temporal trend in the proportion of multiple births after MAR over time, a linear regression model was employed separately for different types of techniques and in strata of maternal age.
    RESULTS: A total of 30,900 births after MAR were included; 4485 (14.5 %) first line treatments and 26,415 (85.5 %) IVF techniques. Overall, 4823 (15.6 %) multiple births were identified. The frequency of multiple births over the study period decreased from 22.0 % in 2007 to 8.7 % in 2022 (p < 0.01). Multiple births from first line treatments were stable ranging from 13.5 % in 2007-2008 to 12.0 % in 2021-2022 (p = 0.29). Multiple births from IVF procedures decreased from 23.8 % in 2007-2008 to 8.4 % in 2021-2022 (p < 0.01). Stratifying for maternal age (i.e. < 35 and ≥ 35 years), the trends remained consistent.
    CONCLUSIONS: The reduction in multiple births has been influenced by changes in IVF strategy and procedures. The decline has been gradual but steady since 2009, when a law restricting embryo freezing was repealed in Italy. In contrast, the proportion of multiple births resulting from first line treatments has remained constant over time. Despite declining, multiple births from MAR remained about one order of magnitude higher than those from spontaneous pregnancies.
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  • 文章类型: Journal Article
    背景:表观遗传时钟被认为是衰老的有希望的生物标志物,包括由各个CpG站点训练的原始时钟和由CpG站点的PC训练的主成分(PC)时钟。遗传和环境因素对表观遗传时钟的影响尚不清楚。特别是PC时钟。
    方法:我们从中国国家双胞胎注册中心(CNTR)中构建了477对同性双胞胎的单变量双胞胎模型,以估计五个表观遗传钟(GrimAge,PhenoAge,DunedinPACE,PCGrimAge,和PCPhenoAge)。此外,我们调查了134对同性双胞胎5年中遗传和环境影响对表观遗传时钟的纵向变化。
    结果:表观遗传时钟的遗传力范围为0.45至0.70,PC时钟的遗传力高于原始时钟。对于五个表观遗传时钟,纵向稳定性中等到高,主要是由于遗传效应。基线和后续表观遗传时钟之间的遗传相关性中等到高。在基线和后续行动中都出现了特殊的独特环境因素。PC时钟比原始时钟显示出更高的纵向稳定性和独特的环境相关性。
    结论:对于五个表观遗传时钟,他们有可能识别衰老干预措施。高纵向稳定性主要是由于遗传因素,表观遗传时钟随时间的变化主要是由于独特环境因素的变化。考虑到遗传和环境因素的差异以及PC和原始时钟之间的纵向稳定性,原始时钟的研究结果需要用PC时钟进一步验证。
    BACKGROUND: Epigenetic clocks were known as promising biomarkers of aging, including original clocks trained by individual CpG sites and principal component (PC) clocks trained by PCs of CpG sites. The effects of genetic and environmental factors on epigenetic clocks are still unclear, especially for PC clocks.
    METHODS: We constructed univariate twin models in 477 same-sex twin pairs from the Chinese National Twin Registry (CNTR) to estimate the heritability of five epigenetic clocks (GrimAge, PhenoAge, DunedinPACE, PCGrimAge, and PCPhenoAge). Besides, we investigated the longitudinal changes of genetic and environmental influences on epigenetic clocks across 5 years in 134 same-sex twin pairs.
    RESULTS: Heritability of epigenetic clocks ranged from 0.45 to 0.70, and those for PC clocks were higher than those for original clocks. For five epigenetic clocks, the longitudinal stability was moderate to high and was largely due to genetic effects. The genetic correlations between baseline and follow-up epigenetic clocks were moderate to high. Special unique environmental factors emerged both at baseline and at follow-up. PC clocks showed higher longitudinal stability and unique environmental correlations than original clocks.
    CONCLUSIONS: For five epigenetic clocks, they have the potential to identify aging interventions. High longitudinal stability is mainly due to genetic factors, and changes of epigenetic clocks over time are primarily due to changes in unique environmental factors. Given the disparities in genetic and environmental factors as well as longitudinal stability between PC and original clocks, the results of studies with original clocks need to be further verified with PC clocks.
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  • 文章类型: Case Reports
    CCN6的双等位基因致病变异导致进行性假性肿瘤样发育不良(PPD),一种罕见的骨骼发育不良.主要特征包括非炎性进行性关节僵硬和增大,这并不是这种情况所独有的。几乎100%的报道的变异是单核苷酸变异或小的indels,并且已经报道了第二个变体的缺失。基因组测序(GS)涵盖了各种类型的变异,深度表型(DP)提供了详细而精确的信息,有助于遗传数据解释。GS和DP的结合提高了诊断率,特别是在罕见和未诊断的疾病中。我们鉴定了一种新的复合杂合子,涉及具有单核苷酸变体的反式致病拷贝数变体(g.112057664_112064205del)(c.624dup(p。Cys209MetfsTer21))在一对单卵双胞胎中的CCN6,通过GS和DP的方法。这对双胞胎之前收到了三个非诊断结果。所有测试都错过了g.112057664_112064205del变体,记录的表型不准确甚至误导。这对双胞胎被诊断患有PPD,结束了长达13年的诊断冒险.可能还有其他PPD患者由于基因检测或表型鉴定方法不足而经历诊断不足和误诊。该病例强调了GS和DP在促进准确和及时诊断方面的关键作用。
    Biallelic pathogenic variants in CCN6 cause progressive pseudorheumatoid dysplasia (PPD), a rare skeletal dysplasia. The predominant features include noninflammatory progressive joint stiffness and enlargement, which are not unique to this condition. Nearly 100% of the reported variants are single nucleotide variants or small indels, and missing of a second variant has been reported. Genome sequencing (GS) covers various types of variants and deep phenotyping (DP) provides detailed and precise information facilitating genetic data interpretation. The combination of GS and DP improves diagnostic yield, especially in rare and undiagnosed diseases. We identified a novel compound heterozygote involving a disease-causing copy number variant (g.112057664_112064205del) in trans with a single nucleotide variant (c.624dup(p.Cys209MetfsTer21)) in CCN6 in a pair of monozygotic twins, through the methods of GS and DP. The twins had received three nondiagnostic results before. The g.112057664_112064205del variant was missed by all the tests, and the recorded phenotypes were inaccurate or even misleading. The twins were diagnosed with PPD, ending a 13-year diagnostic odyssey. There may be other patients with PPD experiencing underdiagnosis and misdiagnosis due to inadequate genetic testing or phenotyping methods. This case highlights the critical role of GS and DP in facilitating an accurate and timely diagnosis.
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  • 文章类型: Journal Article
    结合来自同一样品的粉末衍射数据,成功地进行了LaAlO3拟摩面体孪晶晶体的域分辨同步加速器单晶X射线衍射研究。从一个单晶确定从微米到纳米到原子尺度的多尺度结构信息。在低于400K的温度下,畴比几乎没有变化,表明畴壁没有运动。在450至700K的温度范围内观察到指示畴壁运动的畴比变化,这与之前的机械测量结果一致。还发现四个孪生组分的比例变得相等(25%),低于相变温度。这些发现对于与LaAlO3相关的领域工程和理论研究具有重要意义。除第一加热过程至840K外,在加热和冷却循环中保留了畴比的温度依赖性。因此,加热到840K后的畴结构是晶体固有的。通过晶胞参数校准和域分辨结构分析确定了精确的结构参数。推导了从双晶数据中校准晶胞参数的方法,并将其用于解决当前和以前研究中单晶和粉末数据之间的晶胞参数不一致的问题。
    A domain-resolved synchrotron single-crystal X-ray diffraction study of a LaAlO3 pseudo-merohedral twin crystal was successfully carried out in combination with powder diffraction data from the same sample. Multiscale structure information ranging from micro- to nano- to atomic scale was determined from one single crystal. There is almost no change of domain ratios at temperatures of less than 400 K indicating no movement of the domain wall. The changes in domain ratio indicating domain-wall movement were observed in the temperature range of 450 to 700 K, which is consistent with the result of the previous mechanical measurement. It is also found that the ratio of four twin components becomes equal (25%), just below phase transition temperature. These findings are important for domain engineering and theoretical studies related to LaAlO3. The temperature dependence of domain ratio was preserved in the heating and cooling cycle except for the first heating process to 840 K. Therefore, the domain structure after heating to 840 K is intrinsic to the crystal. Accurate structure parameters were determined through unit-cell parameter calibration and domain-resolved structure analysis. The method for calibration of unit-cell parameters from twin crystal data was derived and used to solve the inconsistent unit-cell parameters between single crystal and powder data in the present and previous studies.
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