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Pregnancies ending before 26 weeks contribute 1% of births but 40% of infant deaths in the United States. The rate of these periviable births to non-Hispanic (NH) Black women exceeds four times that for NH whites. Small male periviable infants remain most likely to die. NH white periviable males weigh more than their NH Black counterparts. We argue that male infants born from twin gestations, in which one fetus died in utero (i.e., the vanishing twin syndrome), contribute to the disparity. We cannot directly test our argument because vanishing typically occurs before clinical recognition of pregnancy. We, however, describe and find associations that would emerge in vital statistics were our argument correct. Among male periviable singleton births from 288 monthly conception cohorts (January 1995 through December 2018), we found an average NH white advantage of 30 grams (759 grams versus 729 grams). Consistent with our argument, however, cohorts signaling relatively few survivors of the vanishing twin syndrome showed no disparity.

ObjectiveDespite an increase in twin pregnancies in recent decades, the Institute of Medicine twin weight gain recommendations remain provisional and provide no guidance for the pattern or timing of weight change. We sought to characterize gestational weight change trajectory patterns and examine associations with birth outcomes in a cohort of twin pregnancies.Study designPrenatal and delivery records were examined for 320 twin pregnancies from a maternal-fetal medicine practice in Austin, TX 2011-2019. Prenatal weights for those with >1 measured weight in the first trimester and ≥3 prenatal weights were included in analyses. Trajectories were estimated to 32 weeks (mean delivery: 33.7 ± 3.3 weeks) using flexible latent class mixed models with low-rank thin-plate splines. Associations between trajectory classes and infant outcomes were analyzed using multivariable Poisson or linear regression.ResultsWeight change from prepregnancy to delivery was 15.4 ± 6.3 kg for people with an underweight body mass index, 15.4 ± 5.8 kg for healthy weight, 14.7 ± 6.9 kg for overweight, and 12.5 ± 6.4 kg for obesity. Three trajectory classes were identified: low (Class 1), moderate (Class 2), or high gain (Class 3). Class 1 (24.7%) maintained weight for 15 weeks and then gained an estimated 6.6 kg at 32 weeks. Class 2 (60.9%) exhibited steady gain with 13.5 kg predicted total gain, and Class 3 (14.4%) showed rapid gain across pregnancy with 21.3 kg predicted gain. Compared to Class 1, Class 3 was associated with higher birth weight z-score (β = 0.63, 95% confidence interval [CI]: 0.31,0.96), increased risk for large for gestational age (IRR = 5.60, 95% CI: 1.59, 19.67), and birth

The sleep homeostatic process in adults is moderately stable over time and unique to an individual. Work in transgenic mice has suggested a role of genes in sleep homeostasis. The current study quantified the genetic contribution to sleep homeostasis in adolescence. We use slow wave energy (SWE) as a metric for sleep pressure dissipation during sleep. This measure reflects both sleep intensity and duration. High‐density (58 derivations) sleep electroencephalogram (EEG) was recorded in 14 monozygotic and 12 dizygotic adolescent twin pairs (mean age = 13.2 years; standard deviation [SD] = 1.1; 20 females). SWE at the end of sleep was quantified as the cumulative delta power (1–4.6 Hz) over the night. We also examined the time constant of the decay and the level of slow wave activity (SWA) at the beginning of the sleep episode. Structural equation modelling was used to quantify the amount of variance in SWE and the dissipation of sleep pressure due to genes. We found that most (mean = 76% across EEG derivations) of the variance in SWE was due to genes. In contrast, genes had a small (mean = 33%) influence on the rate of dissipation of sleep pressure, and this measure was largely (mean = 67%) driven by environmental factors unique to each twin. Our results show that the amount of dissipated sleep pressure is largely under genetic control; however, the rate of sleep pressure dissipation is largely due to unique environmental factors. Our findings are in line with research in animals and suggest that the heritability of the rate of sleep pressure dissipation is limited. [ABSTRACT FROM AUTHOR]

Hypertrophic cardiomyopathy (HCM) is a prevalent genetic cardiovascular disease characterized by asymmetric thickening of the left ventricular wall, frequently occurring in families predisposed genetically. While HCM in twins is rare, it presents a unique opportunity to explore the disease's genetic and epigenetic underpinnings due to the phenotypic heterogeneity observed even among genetically identical individuals. This review collates and analyzes global clinical studies that focus on the twin phenomena in HCM. It explores the genetic foundations of HCM, examines the influence of environmental and epigenetic factors on disease expression, and emphasizes the crucial role of genetic screening in the early and differential diagnosis of HCM. By focusing on twin cases in HCM, this review aims to enhance our understanding of HCM's complex genetic background, which could lead to more personalized approaches in the management and treatment of this condition, thus drawing significant interest from researchers and clinicians alike. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Objectives: Twin pregnancies are at higher risk of stillbirth compared to singletons. Fetal growth restriction (FGR) is a major cause of perinatal mortality, but its impact on twins vs singletons remains unclear. The primary objective of this study was to investigate the association of FGR and small‐for‐gestational age (SGA) with stillbirth in twin compared with singleton pregnancies. A secondary objective was to assess these associations stratified by gestational age at delivery. Furthermore, we aimed to compare the associations of FGR and SGA with stillbirth in twin pregnancies using twin‐specific vs singleton birth‐weight charts, stratified by chorionicity. Methods: This was a retrospective cross‐sectional study of pregnancies receiving obstetric care and giving birth between 1999 and 2022 at St George's Hospital, London, UK. The exclusion criteria included triplet and higher‐order pregnancies, those resulting in miscarriage or live birth at ≤ 23 + 6 weeks, termination of pregnancy and missing data regarding birth weight or gestational age at birth. Birth‐weight data were collected and FGR and SGA were defined as birth weight <5th and <10th centiles, respectively. While standard logistic regression was used for singleton pregnancies, the association of FGR and SGA with stillbirth in twin pregnancies was investigated using mixed‐effects logistic regression models. For twin pregnancies, intercepts were allowed to vary for twin pairs to account for intertwin dependency. Analyses were stratified by gestational age at delivery and chorionicity. Statistical significance was set at P ≤ 0.001. Results: The study included 95 342 singleton and 3576 twin pregnancies. There were 494 (0.52%) stillbirths in singleton and 41 (1.15%) stillbirths in twin pregnancies (17 dichorionic and 24 monochorionic). SGA and FGR were associated significantly with stillbirth in singleton pregnancies across all gestational ages at delivery: the odds ratios (ORs) for SGA and FGR were 2.36 ((95% CI, 1.78–3.13), P < 0.001) and 2.67 ((95% CI, 2.02–3.55), P < 0.001), respectively, for delivery before 32 weeks; 2.70 ((95% CI, 1.71–4.31), P < 0.001) and 2.82 ((95% CI, 1.78–4.47), P < 0.001), respectively, for delivery between 32 and 36 weeks; and 3.85 ((95% CI, 2.83–5.21), P < 0.001) and 4.43 ((95% CI, 3.16–6.12), P < 0.001), respectively, for delivery after 36 weeks. In twin pregnancies, when stratified by gestational age at delivery, both SGA and FGR determined by twin‐specific birth‐weight charts were associated with increased odds of stillbirth for those delivered before 32 weeks (SGA: OR, 3.87 (95% CI, 1.56–9.50), P = 0.003 and FGR: OR, 5.26 (95% CI, 2.11–13.01), P = 0.001), those delivered between 32 and 36 weeks (SGA: OR, 6.67 (95% CI, 2.11–20.41), P = 0.001 and FGR: OR, 9.54 (95% CI, 3.01–29.40), P < 0.001) and those delivered beyond 36 weeks (SGA: OR, 12.68 (95% CI, 2.47–58.15), P = 0.001 and FGR: OR, 23.84 (95% CI, 4.62–110.25), P < 0.001). However, the association of stillbirth with SGA and FGR in twin pregnancies was non‐significant when diagnosis was based on singleton charts (before 32 weeks: SGA, P = 0.014 and FGR, P = 0.005; 32–36 weeks: SGA, P = 0.036 and FGR, P = 0.008; after 36 weeks: SGA, P = 0.080 and FGR, P = 0.063). Conclusion: Our study demonstrates that SGA and, especially, FGR are associated significantly with an increased risk of stillbirth across all gestational ages in singleton pregnancies, and in twin pregnancies when twin‐specific birth‐weight charts are used. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. Linked article: There is a comment on this article by Nicolaides et al. Click here to view the Correspondence. [ABSTRACT FROM AUTHOR]

Introduction: 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). Material and 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. [ABSTRACT FROM AUTHOR]

Objective: To compare the risk of intrapartum cesarean delivery (CD) between patients with twin and singleton pregnancies undergoing a trial of labor and identify risk factors for intrapartum CD in twin pregnancies. Methods: The present study was a retrospective cohort study of patients with a twin or singleton pregnancy who underwent a trial of labor at ≥340/7 weeks in a single center (2015–2022). The primary outcome was the rate of intrapartum CD. In twin pregnancies, this outcome was limited to CD of both twins. The association of plurality with intrapartum CD was estimated using multivariable Poisson regression. Results: A total of 20 754 patients met the study criteria, 669 of whom had a twin pregnancy. Patients with twins had a greater risk of intrapartum CD (of both twins) than those with singleton pregnancies (22.1% vs 15.9%, respectively; aRR 1.38 [95% CI: 1.15–1.66]), primarily due to a greater risk of failure to progress. In addition, 4.1% of the twin pregnancies had a CD for the second twin, resulting in an overall CD rate in twin pregnancies of 26.2%. Variables associated with intrapartum CD in twin pregnancies included nulliparity (aOR 3.50, 95% CI: 2.34–5.25), birthweight discordance >20% (aOR 2.47, 95% CI: 1.27–4.78), and labor induction (aOR 1.64, 95% CI: 1.07–2.53). The rate of intrapartum CD was highest when all three risk factors were present (67% [95% CI: 41%–87%]). Conclusion: Twin pregnancies are associated with a greater risk of intrapartum CD than singleton pregnancies. Information on the individualized risk of intrapartum CD may be valuable when counseling patients with twins regarding mode of delivery. Synopsis: Twin pregnancies are associated with a greater risk of intrapartum cesarean delivery, primarily due to a greater risk of failure of labor to progress. [ABSTRACT FROM AUTHOR]

This article proposes a methodology for the design of digital twins applicable to various systems (pneumatic, hydraulic, electrical/electronic circuits). The methodology allows representing the operation of these systems through an active digital twin, enabling the simulation, control, and monitoring through a more suitable and powerful computer-aided design. Furthermore, this methodology enables the detection of a system's actions on its own inputs (for instance, in pneumatics: backflow of gases trapped in parts of a fluidic system into its own inputs). During the simulation or monitoring phase, the approach also facilitates real-time diagnosis of the physical system. The outputs of the controlled physical system or its digital twin do not depend only on the current inputs but also on the history of the inputs and the history of internal states and variables. In other words, the underlying sequential behavior logic has a memory while an combinational logic approach alone has not. These modeling capabilities can contribute to the digital transformation of the design, control, simulation, and manufacturing systems. [ABSTRACT FROM AUTHOR]

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Heteropagus, also known as parasitic twining, is the asymmetric twinning of conjoined identical or monozygotic twins. One severely deficient twin (the parasite) relies on the other twin's heart (the autosite) to survive. The circumstance only arises when parts of the body of the developed and delivered twin are joined to the undeveloped or underdeveloped twin. Very few case reports of this uncommon congenital defect have been published in the literature. Here, we describe a case of this atypical entity in a neonate in which the rudimentary pelvis and thigh of the parasite were attached to the autosite of the twin.

Abstract Background Diagnosis of umbilical cord entanglement (UCE) by ultrasound (US) in monochorionic monoamniotic (MCMA) twins in the second and third trimesters is common. However, only a few cases have been reported on the diagnosis of UCE as early as the first trimester. Herein, we report a case of the earliest-ever sonographic diagnosis of UCE and demonstrate the feasibility of its diagnosis by US. Case presentation A 32-year-old gravida 2 para 1 woman conceived after assisted reproductive technology (ART) treatment. In transvaginal US examination at 8.5 gestational weeks, two embryos with regular heartbeats in the same amniotic sac and with only one yolk sac were demonstrated. The fetal crown-rump lengths were 20 and 21 mm, appropriate for 8.4 and 8.5 gestational weeks, respectively. HD-flow power Doppler 2D and 3D US demonstrated two tightly entangled umbilical cords of the two fetuses. Spectral Doppler US showed two different heart rates (162 and 167 beats per minute) and blood flow in opposite directions from the point of entanglement of the two umbilical cords. This was consistent with a diagnosis of a first-trimester MCMA pregnancy with UCE. Missed abortion of the two embryos was diagnosed by US examination at 10.5 weeks, and the pregnancy was terminated by dilatation and curettage without further complications. Conclusions UCE in the first trimester may occur as early as eight gestational weeks, and its diagnosis by ultrasound is feasible. UCE diagnosed in the first trimester may be a poor prognostic factor.

This study investigates the strain rate-dependent deformation behavior of cost-effective twinning-induced plasticity (TWIP) steel, Fe–26Mn-0.4C, at 15 K and reveals intriguing insights into its mechanical properties. The serration type changes from type A to type C with decreasing strain rate, resulting in a quasi-cleavage fracture at the crack initiation site. Microstructural analysis unveils a correlation between strain rate and the evolution of bundle twins, nano-twins, and ε-martensites. These denser networks of deformation twins (DTs) and ε-martensites contribute to impacting the mechanical properties. The mechanism behind the formation of serrations involves a rate-dependent thermal instability effect and the intricate interactions between dislocations and dislocations/Mn–C couples. The distinct findings enhance our understanding of the complex deformation behavior of high-Mn steel at cryogenic temperatures and provide valuable insights into the broader field of high-Mn steel applications in dynamic environments.

Abstract 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.

Objective: This study aimed to assess selenium status in South Korean pregnant women and its impact on maternal thyroid function and pregnancy outcomes. Methods: ‘Ideal Breast Milk (IBM) Cohort Study’ included 367 pregnant women out of 442 participants and categorized into three groups based on plasma selenium levels: deficient (< 70 μg/L), suboptimal (70–99 μg/L), and optimal (≥ 100 μg/L). During the second or third trimester, various blood parameters, including selenium, thyroid-stimulating hormone, free T4, free T3, and anti-thyroid peroxidase antibody levels, were measured. Thyroid parenchymal echogenicity was assessed as another surrogate marker for thyroid autoimmunity using ultrasonography. Results: The median plasma selenium was 98.8 (range: 46.7–206.4) μg/L, and 30 individuals (8%) were categorized as deficient, while 164 (45%) were classified in the suboptimal group. Selenium deficiency was associated with markers of autoimmune thyroiditis, including positive anti-thyroid peroxidase antibody results (13.3 (deficient) vs 4.6 (optimal) %, P = 0.031) and thyroid parenchymal heterogeneity on ultrasound (33.3 (deficient) vs 14.6 (suboptimal) vs 17.3 (optimal) %, P = 0.042), independently of gestational age. The incidence of severe preeclampsia was higher in the group not taking selenium supplements, particularly among those with twin pregnancies, compared to the group taking selenium supplements (0 (selenium supplement) vs 9.0 (no supplement) %, P = 0.015). Conclusion: Pregnant women experience mild selenium deficiency, which can lead to significant health issues including maternal thyroid autoimmunity and obstetrical complications during pregnancy. Guidelines for appropriate selenium intake according to the stage of pregnancy and the number of fetuses are needed.

Copper as one of the major electronic metals will experience electric current stressing during electronics application. The study comprehensively investigated microhardness and electrical resistivity variations of copper under current stressing at current densities 1.4 x 104 and 1.7 × 104 A/cm2 for up to 8 h. The variations in these properties were correlated with dislocation density and twin fraction. The dislocation density and twin fraction were estimated, respectively, with high resolution transmission electron microscope and Electron Backscatter Diffraction. The twin boundary acts as obstacle to dislocation movement as revealed by high resolution transmission electron microscopy. The twin boundary predominates over dislocation in governing the microhardness and electrical resistivity of copper under current stressing.

Enstatite (Mg2Si2O6) is a member of the pyroxene group and an important mineral in the lower crust and upper mantle. Enstatite has three phases at ambient pressure: protoenstatite, orthoenstatite, and clinoenstatite. Previously, the polymorphic transformation of pyroxene has been characterized using bulk techniques such as X-ray diffraction of powders. Given that rocks are crystal aggregates, it is important to use aggregates to understand phase transformations. We therefore conducted grain growth and deformation experiments using aggregates of enstatite to investigate phase transformations. Grain growth experiments were conducted at temperatures (T) of 1345 and 1360 °C under a vacuum of ≈ 10 Pa using an alumina tube furnace. Deformation experiments were conducted at T = 1310 °C and room pressure, a strain rate of ≈ 10–4 s–1, and a resulting stress of ≈ 150 MPa. The samples were analyzed using a scanning electron microscope, electron backscatter diffraction (EBSD), and X-ray diffraction. The results indicate that the grain size affects the transformation from protoenstatite to clinoenstatite, whereas deformation by diffusion creep does not. The EBSD analyses show that the volume fraction of clinoenstatite increases with increasing grain size. The samples underwent diffusion creep during the deformation experiments, and there were no distinct microstructural differences between deformed and undeformed samples. The EBSD analyses show that the transformed clinoenstatite has a characteristic twin structure with a misorientation angle of 180° and a rotation axis of [100] or [001]. Grain sizes become smaller during the phase transformation, even if the mechanism can be characterized as a second-order transformation.Highlights: Grain growth and deformation experiments using aggregates of enstatite crystals were conducted to understand the microstructural developments due to the phase transformation from protoenstatite to clinoenstatite. Grain size influences the transformation, whereas deformation by diffusion creep does not. Grain sizes become smaller during the phase transformation, even if the mechanism can be characterized as a second-order transformation. [ABSTRACT FROM AUTHOR]

Understanding background factors is beneficial for interpreting general movements (GMs). This study examines the factors involved in preterm-writhing GMs by comparing twins and singletons. The subjects were 107 infants cared for at Oita University. The cohort consisted of very-low-birth-weight infants, including twins with a birth weight < 2000 g. The median gestational age (GA) was 29 weeks 1 day. The subjects consisted of 75 singletons, 32 twins (16 pairs), 20 monochorionic twins (M−twins), and 12 dichorionic twins (D-twins). GMs were scored according to the GMs optimality score (GMOS) and integrated into 6 items: the quality, neck-trunk and space, amplitude-speed, rotation, onset-offset and cramped, and tremulous score at 32–34 weeks, 35–36 weeks, and 37–42 weeks' GA. A hierarchical cluster analysis was performed using integrated GMOS, and the characteristics of clusters were examined according to clinical backgrounds. Three clusters were identified. Cluster 1 was characterized by good-quality GMs, cluster 2 by a poor repertoire but optimal space and rotatory components, and cluster 3 by overall poor-quality GMs, respectively. The mean GMOSs were 36.6, 31.8 and 24.3 in clusters 1, 2, and 3, respectively. There were no marked differences in proportions within clusters with respect to sex and twins. Small-for-gestational age (SGA) was significantly more frequent in cluster 3 at 32–34 weeks' GA than in other clusters. Perinatal brain injury had a significantly lower proportion in cluster 1 and a higher proportion in cluster 3 at 35–36 weeks' GA and 37–42 weeks' GA. M−twin pairs tended to belong to the same clusters at 35–36 weeks' GA. Preterm writhing GMs are associated with SGA and perinatal brain injury. Cluster matching in M−twins suggests that certain genetic factors may substantially influence GMs. [ABSTRACT FROM AUTHOR]

• The use of medically assisted reproduction (MAR) has been associated with higher rates of multiple pregnancy. This is due to the use of fertility drugs to stimulate the ovaries, resulting in the release of multiple eggs during a single menstrual cycle, as well as the transfer of multiple embryos. • Changes in IVF procedure strategies, such as single embryo transfer, have contributed significantly to the decline in multiple pregnancies. However, the percentage of multiple pregnancies resulting from first line treatments has remained relatively constant over time. • Despite declining, multiple births resulting from MAR remained about one order of magnitude higher than those resulting from spontaneous pregnancies. Further efforts are needed to reduce multiple pregnancies in infertility treatment. 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. 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. 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. 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. [ABSTRACT FROM AUTHOR]

This study investigates the association between maternal exposure to particulate matter (PM 10) and nitric dioxide (NO 2) 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 PM 10 or NO 2 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. PM 10 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 PM 10 and NO 2 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. • Effects of NO 2 /PM 10 on placental weight differ for twins with one or two placentas. • The effects of air pollutants are most pronounced in twins born between 32 and 36 weeks. • Higher NO 2 /PM 10 exposure in the last trimester is linked to lower placental weight. • NO 2 /PM 10 exposure in early pregnancy is linked to a lower odds for "SGA-placenta". • NO 2 /PM 10 exposure in late pregnancy is linked to a higher odds for "SGA-placenta". [ABSTRACT FROM AUTHOR]

The effects of different deformation temperatures on the dynamic recrystallization (DRX) behavior and twinning of Incoloy 800H alloy were investigated by hot compression tests. The microstructures at different deformation temperatures were analyzed using electron backscattered diffraction. Additionally, the evolution characteristics of dislocations and twinning were observed by transmission electron microscopy (TEM). The research has found that the DRX behavior becomes more pronounced with the increase in deformation temperatures. At lower temperatures, discontinuous DRX (DDRX) promotes DRX along with continuous DRX (CDRX). As the temperature increases, the CDRX mechanism gradually weakens, and the DDRX mechanism becomes dominant. Furthermore, it can be observed through TEM that as the deformation temperature increases, the initial twins are gradually disappear and new twins formed inside the DRX grains, which promotes the microstructure's refinement. [ABSTRACT FROM AUTHOR]

Purpose: The "en caul" cesarean section (CS) is a method to keep the amnion intact during CS. This amnion protection effect may have benefits in preterm twin pregnancy. This study aimed to explore the benefits and risks of this method in preterm twin pregnancy. Methods: This study is a retrospective analysis of preterm twin pregnancies underwent CS in West China Second University Hospital of Sichuan University from January 2011 to December 2022. Data on maternal and fetal outcomes were collected. Univariable analyses and multivariate logistic regression analyses were applied. The level of significance was set at p < 0.05. Results: A total of 182 patients were included (90 in the "en caul" group, 92 in the conventional group). "en caul" CS was associated with lower incidence for respiratory distress (aOR 0.47, 95% CI 0.25–0.88, for the first fetus; aOR 0.42, 95% CI 0.21–0.82, for the second fetus). This method was proved to have beneficial effects in improving the Apgar scores at 1st minute and reducing the mechanical ventilation rate in the second neonates (aOR 0.41, 95% CI 0.19–0.88). Conclusion: "En caul" CS is an easy and safe technique to perform during CS for preterm twin pregnancy. The efficacy and safety of this method could be tested by future studies with larger sample size. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

To investigate the effects of laser peening (LP) on the surface and bending fatigue properties of carburized steel (JIS SCM420), surface roughness measurements, residual stress measurements, retained austenite measurements, and four-point bending fatigue tests were conducted. After LP, the compressive residual stress was applied on the surface, with the effect extending to a depth of more than 1 mm. Due to the high compressive residual stress, the bending fatigue strength of LP specimen was 1.46 times higher than that of the gas carburized specimen even though the surface roughness was increased by LP. Notably, the amount of retained austenite was 10.9% at the outermost surface of LP specimen, and high-density twins were observed in the lath martensite structure. This can be attributed to high strain rate deformation by LP. [ABSTRACT FROM AUTHOR]

Objective: Single intrauterine fetal death Background: One of the obstetric complications of twin pregnancy is the intrauterine death of one fetus. A death that occurs in the first trimester usually leads to fewer complications than a death in the second and third trimester. In the second and third trimesters, single fetal death of twin pregnancy was reported to increase the death, preterm birth, and neurological injury of the surviving co-twin. Although rare, it can trigger a coagulation defect in the mother as well. Neurological morbidities were also more common in monochorionic twins than in dichorionic gestation. Thus, a consideration of pregnancy termination might persist. Case Report: We present a case of a primigravida woman with a monochorionic twin pregnancy with intrauterine death of one fetus at 20-21 weeks of gestation. We treated this patient with pregnancy continuation under close monitoring for more than 12 weeks, until she delivered the surviving baby at term. The outcome of the surviving baby was a normal condition and appropriate weight, and no fetal morbidity, and there was no maternal morbidity related to coagulation disorder in the mother. Conclusions: Conservative management under close monitoring until term in monochorionic twin pregnancy with single fetal death could be the best option to obtain a favorable outcome. We recommend conservative management with close surveillance monitoring using non-stress tests after 32 weeks, biweekly ultrasound, and at least one maternal coagulation profile test. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Introduction: The initiation and continued use of tobacco products constitute an ongoing source of preventable disease that continues to pose a significant risk to global adolescent health. Scarce research has sought to explore the influences of two well‐known environmental risk factors, parental supervision and peer cigarette use, on genetic and environmental contributions to adolescent cigarette use, especially in non‐Western populations. Methods: Following 602 Chinese twin pairs (52% female, N = 1204) from early to middle adolescence at two‐time points (Mage = 12 and 15) from 2006 to 2009 and using multivariate biometric modeling, this study examined gene–environment interplay (i.e., gene‐environment correlation and interaction) between perceived parental supervision, peer cigarette use, and adolescent cigarette smoking initiation. Results: From early to middle adolescence, genetic influences on cigarette smoking initiation became more pronounced, whereas shared environmental influences that promote similarity between family members diminished. Genetic factors primarily explained the links between parental supervision and cigarette smoking initiation in mid‐adolescence. Peer cigarette use displayed stronger associations with and moderating potential in adolescent cigarette smoking initiation than parental supervision. High levels of peer cigarette use amplified genetic risk for cigarette smoking initiation in mid‐adolescence. Conclusions: Chinese adolescent cigarette smoking initiation involves dynamic gene–environment transactions primarily with peer processes over development. Mid‐adolescence constitutes a developmental period wherein underlying genetic risk for cigarette smoking initiation is particularly sensitive to peer influences. Targeted interventions aimed at reducing Chinese adolescent cigarette smoking initiation should focus on peer processes during this developmental period. [ABSTRACT FROM AUTHOR]

INTRODUCTION: 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. DISCUSSION: 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. Highlights: 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. [ABSTRACT FROM AUTHOR]

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BACKGROUND: Twin pregnancies compared to singleton pregnancies are characterized by a higher incidence of complications, particularly fetal growth retardation [1]. The main causes of discordance and fetal growth retardation are considered to be differences in the size of placental sites, leading to uneven metabolism of substances and blood, as well as disorders of fetal blood supply caused by vascular anastomoses in the placenta [2, 3]. Computed tomography with the administration of contrast agents can be an effective method to assess the angioarchitectonics and vascularization of the placenta after delivery [4]. AIM: The aim of this study is to conduct a comprehensive computed tomography and morphological evaluation of the vascularization features of monochorionic diamniotic placentas with discordant neonatal weight. MATERIALS AND METHODS: This study was based on the analysis of 33 monochorionic diamniotic placentas obtained after delivery at 27–37 weeks of gestation using the original complex computed tomography and morphological method of investigation [5]. Upon obtaining the placenta, its mass and size of placental sites were determined, as well as the type of attachment, length, diameter, and degree of cord tortuosity. Prior to the computed tomography examination, the umbilical cord and its major branches were cleared of blood clots. The placenta was then immersed in a 10% hypertonic sodium chloride solution and placed on hygroscopic material. Subsequently, contrast dye mixtures of varying colors and concentrations were gradually injected into the unpaired umbilical vein, followed by the umbilical arteries in a sequential manner. The contrast dye mixtures consisted of a water-soluble radiopaque contrast agent, iodixanol, in an aqueous solution of gouache dye. The concentration of the contrast agent in the mixture for injection into the umbilical arteries was 70%, while in the vein it was 15%. The first and second placentae were injected with red and yellow gouache dyes, respectively, into the arteries of the umbilical cord, while blue and green gouache dyes were used for the veins. Following each injection of the contrast dye mixture into the umbilical cord vessel, a visual assessment of the vessel’s branching was conducted, followed by computed tomography on a Toshiba Aquilion ONE 640 (Pediatric 0.5 software package according to the Abdomen Baby study protocol). The final stage involved a traditional macroscopic and microscopic examination of the placenta [6]. RESULTS: The study revealed that the mean value of birth weight discordance in twins was 22.7 ± 2.1%, while placental site discordance was 26.6 ± 5.0%. Vascular anastomoses were identified in 74.2% of twin placentas. Of these, 19 cases exhibited one anastomosis, three cases demonstrated two anastomoses, and one case exhibited five anastomoses. Arterio-arterial anastomoses were observed with greater frequency, while veno-venous and arteriovenous anastomoses were observed with less frequency. The average diameter was 3.7 ± 0.15 mm for arterio-arterial anastomoses, 4.2 ± 0.23 mm for arteriovenous anastomoses, and 4.6 ± 0.26 mm for venous-venous anastomoses. CONCLUSIONS: The use of the developed complex method, which includes computed tomography and the subsequent construction of three-dimensional models of placental vessels and spectral color maps, allows for the visualization of the features of placental vascularization, as well as the assessment of the type and size of existing anastomoses. In monochorionic diamniotic placentas with fetal discordance, a high frequency of abnormal umbilical cord attachment and vascular anastomoses was detected.

Inhomogeneities in the near-surface region of diffusion-doped silicon with manganese atoms were studied using the local photo-EMF method and photovoltage and photoconductivity signals were detected. It has been established that the inhomogeneous region is located at a depth of 3÷35 μm from the surface of the crystal. The magnitude of photo-EMF in these layers does not change monotonically from point to point. It was revealed that the photo-EMF spectra depend on the wavelength of the irradiated light, while the shape of the areas and their shift are related to the penetration depth of laser radiation. The photo-EMF signal increases to a depth of ~25 µm from the surface, then saturates and from ~30 µm smoothly decreases and completely disappears at a depth of ~40 µm. The magnitude of the internal electric field was determined using the Tauc method. A model of the structure of the near-surface region of diffusion-doped silicon with manganese is proposed.

The effects of precipitates at {10 1‾ 2} twin boundaries on twin stability and yield strength of a Mg-Nd-Ag-Zr alloy are investigated by transmission electron microscopy and electron back-scattered diffraction. Twin-boundary precipitates are observed in the pre-deformed alloys after subsequent ageing treatments over a temperature range of 200–450 °C. Such twin-boundary precipitates significantly enhance the thermal stability of {10 1‾ 2} twins, which remain relatively stable even at 480 °C. The stress stability of {10 1‾ 2} twins is also improved due to the pinning effect of the twin-boundary precipitates, leading to a strengthening effect on the alloy. More twin boundaries can be introduced via pre-deformation at a much higher strain rate of 1000 s−1, and such dynamic pre-compression with subsequent ageing treatments is more effective in improving the yield strength due to the formation of more stable {10 1‾ 2} twin boundaries.

(The importance of) is the research to highlight a new technology that increases the life -long life of the products, which is the 'Digital twin' technology. Reducing the cost of design, testing, product samples, and reducing operating cost. Predicting the product breakdowns before it happens and reduces the cost of its maintenance. Protect the worker when using some dangerous machines. Monitor the product or the system remotely without the need to be next to it. One of the (goals) was the research to develop the method of maintenance of products to the digital technology 'digital twin' because of its great impact on prolonging the life of the product, maintaining its safety and improving its performance and protecting the user, reducing the costs of both (design, production, maintenance). Achieving safety in all product tests. Teaching that technology for students of industrial design for their experience that helps them to understand that technology, and implement it in a simplified, uncomplicated manner. As for the most important (results), it was an explanation of a new technology for the industrial designer that appeared in the world that would develop the method of maintenance of products to digital maintenance first, and to clarify the importance of that technology in prolonging the default life of the product, reducing design costs, production, maintenance, and getting rid of the problem of sudden stopping of the product during the work. Access to a methodology.

ObjectiveTwin vaginal deliveries (VDs) are often performed in the operating room (OR) given the theoretical risk of conversion to cesarean delivery (CD) for the aftercoming twin. We aim to evaluate the cost-effectiveness of performing VDs for twin gestations in the labor and delivery room (LDR) versus OR.Study designWe conducted a cost-effectiveness analysis using a decision-analysis model that compared the costs and effectiveness of two strategies of twin deliveries undergoing a trial of labor: (1) intended delivery in the LDR and 2) delivery in the OR. Sensitivity analyses were performed to assess strength and validity of the model. Primary outcome was incremental cost-effectiveness ratio (ICER) defined as cost needed to gain 1 quality-adjusted life year (QALY).ResultsIn the base-case scenario, where 7% of deliveries resulted in conversion to CD for twin B, attempting to deliver twins in the LDR was the most cost-effective strategy. For every QALY gained by delivering in the OR, 243,335 USD would need to be spent (ICER). In univariate sensitivity analyses, the most cost-effective strategy shifted to delivering in the OR when the following was true: (1) probability of successful VD was less than 86%, (2) probability of neonatal morbidity after emergent CD exceeded 3.5%, (3) cost of VD in an LDR exceeded 10,500 USD, (4) cost of CD was less than 10,000 USD, or (5) probability of neonatal death from emergent CD exceeded 2.8%. Assuming a willingness to pay of 100,000 USD per neonatal QALY gained, attempted VD in the LDR was cost effective in 51% of simulations in the Monte Carlo analysis.ConclusionTwin VDs in the LDR are cost effective based on current neonatal outcome data, taking into account gestational age and associated morbidity. Further investigation is needed to elucidate impact of cost and outcomes on optimal utilization of resources.Key points· Cost effectiveness of twin VDs in the LDR versus OR was assessed.. · Twin VDs in the LDR are cost effective based on current neonatal outcome data.. · Attempted VD in the LDR was cost effective in 51% of simulations in the Monte Carlo analysis..

(1) Background: The transition to twin parenthood is a demanding challenge with a higher risk of maternal and fetal complications during pregnancy and a postpartum period that involves caring for more than one newborn at the same time with similar and simultaneous needs. (2) Aim: To find out about parents' needs when experiencing the transition to twin parenthood and to describe the intervention of their specialized nursing support network. (3) Methodology: A descriptive exploratory study, based on a proper non-probabilistic sample of 15 nurses and 55 couples who are parents of twins, using two online questionnaires publicized on social networks. (4) Results: The couple's needs were identified through knowledge of their experiences and difficulties during pregnancy and after the twin birth. Couples' and nurses' perceptions differed on the identified needs. The specialized nursing support network focuses its intervention on providing informative guidance on twin pregnancy and postpartum period, health education, group sharing experiences, home visits, planning, and including a family support network in the management of twin care and the creation of a daily routine. (5) Conclusions: There is a need to implement a program focused on the needs of parents of twins, promoting realistic expectations for the birth and parenting of twins, preparing parents, improving their well-being, and creating a specialized nursing support network available to this population. [ABSTRACT FROM AUTHOR]

This study describes the case of a student with congenital intestinal perforations and her experience with inclusive education in the Czech Republic. She is also a sister of an identical twin with cerebral palsy. The data were gained from semi-structured interviews and bio-graphical narratives of the student during her studies at the grammar school and from her parents. Van Manen's analyses of lived experiences was used to identify important themes for each participant. The overarching themes present in their narratives concerned Lucy's future and the choice of the most appropriate educational environment. The parents' narratives focused more on barriers to inclusive education, benefits of inclusive environments, medical and educational care and family support based on close cooperation with school. For Lucy, the dominant theme was being a sister with a less severe disability and caretaking of her sister. In addition to enhancing the understanding of different needs of a student with congenital malformations and her parents' experiences with inclusive education, it helped us to explore how the specific sibling's constellation within her family and school contexts impacts her personal perspective on life, driven strongly by a wish for independence. [ABSTRACT FROM AUTHOR]

Context The risk of gestational diabetes mellitus (GDM) in twin pregnancies is more than double that of singleton pregnancies. Although twin pregnancies present unique challenges for fetal growth and prenatal management, the approach to GDM diagnosis and treatment is the same regardless of plurality. Data on pregnancy outcomes for individuals with GDM and a twin pregnancy are limited and conflicting. Objective To describe the maternal characteristics associated with GDM in twin pregnancies and to assess the associated pregnancy outcomes compared to twin pregnancies unaffected by GDM. Methods A retrospective cohort study was conducted at Mayo Clinic, Rochester, Minnesota, USA, and included predominantly Causasian women aged 18 to 45 years who received prenatal care for a twin pregnancy from 2017-2022. Maternal characteristics and a broad spectrum of pregnancy outcomes were evaluated. Universal GDM screening involved a 50 g oral glucose challenge test +/− a 100 g oral glucose tolerance test. Results GDM was diagnosed in 23% pregnancies (n = 104/452). Compared to those without, women with GDM had known risk factors including a higher prepregnancy body mass index (31.1vs 26.3 kg/m2; P <.01) and a prior history of GDM (21.7 vs 5.9%; P <.01). There were no differences in maternal pregnancy complications or neonatal outcomes between groups. Attendance at postpartum glucose testing among women with GDM was poor at 27.9% (29/104). Conclusion These data suggest that women with twin pregnancies share a similar GDM risk profile to those with singleton pregnancies and provide reassuring evidence that current management for GDM twin pregnancies produces similar outcomes to twin pregnancies without GDM. [ABSTRACT FROM AUTHOR]

To investigate factors associated with outcome of second twin during labour. The study was a retrospective cohort study in a single tertiary centre in Malaysia from 2014 until 2018 involving all twin pregnancies delivered at or more than 24 weeks of gestation. Total of 409 twin pregnancies were included. Dichorionic twin comprises of 54.5 % (n=223) and 45.5 % (n=186) are monochorionic. Women with dichorionic pregnancies are significantly older (p<0.001), have more pre-existing medical disorders (p=0.011) and fetal structural anomalies (p=0.009). Monochorionic pregnancies are significantly more amongst Malay (p=0.01) and conceived spontaneously (p<0.001). There are significantly more fetuses both in cephalic presentation (p=0.026), birthweight discrepancy more than 20 % (p=0.038) and shorter mean inter-twin delivery duration (p=0.048) in monochorionic pregnancies. Second twin delivered with Apgar score <7 is significantly more in dichorionic pregnancies (p=0.006). The second twin is associated with lower birthweight, small for gestational age and arterial cord pH<7.25. Within the group of women who delivered both fetuses vaginally, there was significantly more second twins with intertwin delivery duration less than 30 min who were delivered vaginally without instrumentation (p=0.018). There was significantly more second twin with intertwin delivery duration of 30 min and more with arterial cord pH<7.25 (p=0.045). Those who delivered spontaneously had inter-twin delivery duration within 15–29 min. The outcome of second twin is not influenced by type of twin, gestational age at delivery, inter-twin delivery duration, mode of delivery and presentation at birth. The neonatal outcome for the second twin at birth is not influenced by type of twin, gestational age at delivery, inter-twin delivery duration, mode of delivery and presentation at birth in a cohort managed with non-active management of the second twin in Malaysia. [ABSTRACT FROM AUTHOR]

Introduction: Our objective was to investigate outcomes in twin‐to‐twin transfusion syndrome (TTTS) treated with fetoscopic laser surgery (FLS) at <18 weeks vs ≥18 weeks, and to conduct subgroup analysis of TTTS with FLS at <16 weeks vs 16–18 weeks. Material and methods: PubMed, Scopus and Web of Science were searched systematically from inception until May 2023. Primary outcome was survival, and secondary outcomes included preterm premature rupture of membranes (PPROM), preterm birth and gestational age (GA) at delivery. Results: Nine studies encompassing 1691 TTTS pregnancies were included. TTTS stage III was significantly more common in TTTS pregnancies treated with FLS at <18 weeks (odds ratio [OR] 2.84, 95% confidence interval [CI] 1.24–6.54), and procedure duration was shorter at <18 weeks (MD −5.27 minutes, 95% CI −9.19 to −1.34). GA at delivery was significantly earlier in TTTS pregnancies treated with FLS at <18 weeks (MD −3.12 weeks, 95% CI −6.11 to −0.13). There were no significant differences in outcomes, including PPROM, PPROM at <7 days post‐FLS, preterm birth at <28 and <32 weeks, delivery at <7 days post‐FLS, and survival outcomes, including fetal demise, live birth and neonatal survival. Similarly, TTTS stage III was more common in TTTS with FLS at <16 weeks than at 16–18 weeks (OR 2.95, 95% CI 1.62–5.35), with no significant differences in the aforementioned outcomes. Conclusions: In early TTTS treated with FLS, outcomes were comparable between those treated at <18 weeks compared with ≥18 weeks except for GA at delivery, which was 3 weeks earlier. In the subset treated at <16 weeks vs 16–18 weeks, the procedure was feasible without an increased risk of very early preterm birth or perinatal mortality. [ABSTRACT FROM AUTHOR]

Objective To explore the clinical characteristics of multiple-birth preterm infants with necrotizing enterocolitis (NEC) and examine the effects of multiple births on clinical manifestations and outcomes of NEC infants. Methods In this retrospective study, 234 premature infants with NEC admitted to Shanghai Children's Hospital from July 2014 to June 2021 were included as research objects, among which 79 were multiple premature infants with NEC and 155 were single premature infants with NEC, According to the presence of single/multiple birth, they were divided into two groups of singleton (group A, n = 155) and multiple-birth (group B, n = 79). Twin group of vaginal delivery was divided into primary birth (group C, n = 9 and secondary birth (group D, n = 4) based upon birth order. Twin group was also assigned into two groups of higher birth weight (group E, n = 20) and lower birth weight (group F n = 45. And twin group was divided into two groups of concordant twins (CT, group G, n = 42 and discordant twins (DT, group H, n = 26). The latter group was further divided into DT with higher birth weight (group l, n = 5 and DT with lower birth weight (group J,n= 21). Demographic profiles (birth weight, gestational age & birth mode), clinical data (time of NEC onset, laboratory results & Bell stage), treatment (medical or surgical, intestinal perforation & extent of disease) and outcomes (postoperative complications & in-hospital mortality) were recorded. Results Seventy-nine cases of multiple preterm NEC infants were recruited, including 75 twins and 4 triplets. Seventy-five preterm NEC twins had a mean gestational age of 31. 60 weeks and a mean birth weight of 1 476.51 gram. Bell stage was 1 (n= 35), II (n = 21) and III n = 19 Eighteen cases (24%) underwent operation. As compared with group A, NEC infants in group B had a lower birth weight [1618.77 ± 481.30) g. (1 479.34 ±376.88) g, P = 0.016], higher rates of cesarean delivery [84(54.2%) vs. 65 (82.3%), P < 0.001 ] and assisted reproductive technology [11(7.1%) vs. 21 (26.6%) P < 0.001 ]. However, no differences existed in demographic profiles, clinical manifestations, laboratory results, Bell stage, surgery or outcomes (P > 0.05). There was no significant effect of birth order on demographic profiles, clinical manifestations, laboratory results, Bell stage, surgery or outcomes (P > 0.05) As compared with group E, group F had a lower birth weight [(1677.65 ±458.23) gus. (1382.89±300.81) g,P=0.019], lower WBC count [(12.31 ±4.22) ts. (9.13 plus/minus 4.01) * 109/L P = 0.023], greater intestinal lesion [5(45.4%) ts.0(0.0%), P = 0.002 ] and more postoperative complications [11(100%) 18. 3 (42.9%), P = 0.011 ] No difference existed in demographic profiles, clinical manifestations, other laboratory results, Bell stage, surgery or in-hospital mortality (P > 0.05). As compared with group G, group J had a greater gestational age [(30.95±2.44), (32.71 ±2.30) week, P = 0.027 ] and a higher rate of cesarean delivery [30 (71.4%) ts. 20 (95.2%) P = 0.045) rfloor. However, no differences existed in demographic profiles, clinical manifestations, laboratory results, Bell stage, surgery or outcomes (P > 0.05) Conclusions Multiple-birth NEC infants have no greater severity of Bell stage, more surgery, greater extent of intestinal lesion, more postoperative complications or higher in-hospital mortality. Twins with lower birth weight are prone to greater extent of intestinal lesion and more postoperative complications. However, birth order and discordance of twins have no significant effect on disease severity, surgery or in-hospital mortality. [ABSTRACT FROM AUTHOR]

Background & Objective: An unusual manifestation of prenatal trophoblastic illness is a twin molar pregnancy with a live fetus and a hydatidiform mole. Due to increased ovulation stimulation, this unusual scenario is rising. Most hydatidiform moles are complete with a fetus, while 0.005 to 0.01% of gestations have a partial mole. This report examined the clinical appearance and outcome of live fetuses with molar pregnancies. Materials & Methods: This study was done at Adiwaniyah, where the Maternity and Pediatrics Teaching Hospital has one obstetrics center. The researcher reviewed 20 years of obstetric reports and found 12 cases of hydatidiform mole pregnancies, with ultrasound reports and/or postpartum examination of the product of gestation indicating twin pregnancy with a single viable fetus. Results: The average age was 27.00 ±6.87 years, with a range of 18-37 years. The parity breakdown was eight (66.7%) primiparous and four (33.3%) multiparous. The average gestational age upon diagnosis was 19.50 ±3.09 weeks, ranging from 15 to 25 weeks. The average gestational age at delivery commencement was 26.67 ±7.09 weeks, with a range of 17-35 weeks. Seven (58.3%) amniocenteses were normal. Maternal complications included bleeding, anemia, blood transfusion, threatening miscarriage, and pre-eclampsia. End-of-gestation outcomes comprised five (41.7%) living and healthy newborns and three (25.0%) dead babies. There were five (41.7%) men and two (16.7%) women. Moreover, cesarean sections, early labor, and miscarriages were documented. Conclusion: Twin pregnancies with a live viable fetus and a molar pregnancy is rare, hence early detection and care are crucial to prevent difficulties for the mother and fetus. [ABSTRACT FROM AUTHOR]

Multiple pregnancies have a 2-3 times greater risk of developing preeclampsia and have a significant long-term effect on both mothers and babies. The underlying cause of preeclampsia in women with multiple pregnancies is higher demand on the cardiovascular system, increased exposure of the chorionic villi, increased antiangiogenic substances compared to angiogenic substances, and placental hypoperfusion. The condition of preeclampsia can worsen quickly, and without warning signs, it must be detected and managed appropriately; if the treatment is late, this condition can lead to eclampsia. The patient was referred with severe preeclampsia and multiple pregnancies with complaints of irregular contraction (+), a history of dizziness (-), nausea (-), vomiting (-), blurred vision (-), and breathlessness (-). Physical examination showed Blood pressure 188/125 mmHg with laboratory findings of proteinuria +3. Cesarean section and IUD insertion were performed. During and after surgery, there were no complications. [ABSTRACT FROM AUTHOR]

A pregnant woman with hydatidiform mole in one twin was misdiagnosed as one of the twins with embryonic arrest. She chose to terminate the pregnancy and developed distant lung metastasis. After chemotherapy, she eventually recovered. This article systematically analyzes the diagnosis and treatment of hydatidiform mole in one twin to increase the awareness and reduce misdiagnosis of the disease. [ABSTRACT FROM AUTHOR]

The current study was motivated by an interest in deepening understanding of Brazilian twin research, which is underrepresented internationally, in an effort to rectify this situation. Our aim was threefold: (1) to carry out a comprehensive investigation of Brazilian research on twins according to the area of knowledge; (2) to evaluate the representation of research in the field of psychology in comparison with other areas; (3) to evaluate characteristics of the research that may have contributed to its exclusion from the comprehensive meta-analysis of 50 years of twin research. A scoping review was performed according to PRISMA guidelines. Titles and abstracts were searched up to 2022 in six databases: CAPES, BDLTD, PePSIC, PubMed, Google Scholar, and SciELO, using selected keywords both in Portuguese and in English (e.g., 'twins' and 'Brazil'; 'twinning' and 'Brazil'; 'gemelaridade' [twinning], and 'gêmeos' [twins]). Three hundred and forty publications were included in the review. Approximately half (53.8‰) used the classic twin design to investigate the heritability of several traits, and the other half (46.2%) used other research designs. The scoping review showed that the number of publications doubled approximately every 10 years. Most publications were from the health area, with medicine accounting for approximately half of the studies, followed by psychology, odontology, and biology. We found that the interest in studying twins among Brazilian scientists is increasing over the years and there are reasons to be enthusiastic about the potential impact of this trend in the global scenario. [ABSTRACT FROM AUTHOR]

Inhomogeneities in the near-surface region of diffusion-doped silicon with manganese atoms were studied using the local photo-EMF method and photovoltage and photoconductivity signals were detected. It has been established that the inhomogeneous region is located at a depth of 3÷35 μm from the surface of the crystal. The magnitude of photo-EMF in these layers does not change monotonically from point to point. It was revealed that the photo-EMF spectra depend on the wavelength of the irradiated light, while the shape of the areas and their shift are related to the penetration depth of laser radiation. The photo-EMF signal increases to a depth of ~25 μm from the surface, then saturates and from ~30 μm smoothly decreases and completely disappears at a depth of ~40 μm. The magnitude of the internal electric field was determined using the Tauc method. A model of the structure of the near-surface region of diffusiondoped silicon with manganese is proposed. [ABSTRACT FROM AUTHOR]

Congenital malformations are structural defects that occur in all species during fetal development. Pygomelia is a type of polymelia in which the redundant legs are joined to the pelvis. This abnormality is observed in both human beings and animals. A mixed female (Shih Tzu) puppy with a rigid mass resembling two pelvic hindlimbs was referred to a pet clinic in Mashhad City, Iran. In radiographic assessments, two extra hindlimbs stemmed from malformed pelvic bones and were shorter than normal limbs. Both extra acetabula were detected on the hemipelvis, with two extra coxofemoral joints perpendicular to the regular hip joints in the caudal direction. Also, two vulvas and two anuses were seen, but only one vulva and anus were functional. The additional limbs were amputated by surgery. This case is the first report of a dog with incomplete caudal duplication and successful correction of pygomelia in Iran. [ABSTRACT FROM AUTHOR]