bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulation of a non‐linear, time‐variant circuit using the Haar wavelet transform
Authors: Roumeliotis Georgios G. , Desmet Jan , Knockaert Jos 
Published: June 2022

AbstractWavelet theory has disentangled numerous complexities, including those pertinent to transient and steady‐state responses of systems, when Laplace and Fourier transforms face insoluble obstacles. Reactive linear components (e.g. inductors and capacitors) are typically handled in the frequency plane. Non‐linear (e.g. diodes) or time‐variant components (e.g. switches) are conventionally simulated in the time plane (e.g. a diode via its I–V characteristic) and are considered open or short circuits in AC analyses (e.g. in circuit simulation software). Although translating circuits in an alternative plane, such as the Haar wavelet plane, significantly simplifies the process, a wide integration of wavelets into instruments and education is not yet realised; an underlying reason is the considerate complexity of applying wavelet theory to circuits and signals. The aim of this paper is to bridge this gap, providing a new user‐friendly, Laplace‐alike approach, utilising measurement‐based models and the Haar wavelet. The Haar wavelet transform and a numerical method for the inverse Laplace transform which uses the Haar operational matrix are applied, to calculate the total current of a non‐linear, time‐variant system, that is the total current of a voltage source which powers a non‐linear, time‐variant load.
Photochemical Activation of Sulfur Hexafluoride: A Tool for Fluorination and Pentafluorosulfanylation Reactions
Authors: Rombach David , Wagenknecht Hans-Achim 
Published: June 2022

AbstractThe photoactivation of notoriously inert sulfur hexafluoride represents a challenge for photochemistry. This short review summarizes recently published efforts and the corresponding photochemical mechanisms for switching between the fluorination and pentafluorosulfanylation reactivity of organic substrates.1	Introduction2	Sulfur Hexafluoride (SF6)3	The Pentafluorosulfanyl (SF5) Group4	Photoredox Catalytic Activation of SF6
5	Conclusions
Infective Endocarditis in Pregnancy: A Contemporary Cohort
Authors: Countouris Malamo E. , Marino Amy L. , Raymond Megan , Hauspurg Alisse , Berlacher Kathryn L. 
Published: June 2022

Objective Pregnancy-related infective endocarditis (IE) caries a high risk of morbidity and mortality. With increasing intravenous drug abuse (IVDA) amid the opioid epidemic, the risk factor profile may be shifting. In this case series, we aimed to describe risk factors and outcomes for peripartum IE in a contemporary cohort.
Study Design We identified patients with IE diagnosed during pregnancy or up to 6 weeks' postpartum from 2015 through 2018 at a single tertiary care center. We abstracted detailed medical history and clinical outcome measures from the electronic medical record. The diagnosis of IE was supported by the modified Duke Criteria.
Results Nine patients had peripartum IE: eight (89%) with a history of IVDA, one with an indwelling central venous catheter (11%), and one with prior IE (11%). None had preexisting congenital or valvular heart disease. Six (67%) had comorbid hepatitis C. Eight cases (89%) had gram-positive cocci with vegetations involving the tricuspid valve (56%) and both mitral and tricuspid valves (22%). Major complications included shock (33%), mechanical ventilation (44%), septic emboli (67%), and noncardiac abscesses (33%). Two patients underwent valve surgery, and there were two cases of postpartum maternal mortality (22%), one from septic shock and one from intracerebral hemorrhage. While four patients (44%) delivered preterm (average gestational age 35 weeks), most delivered vaginally (89%) with only one requiring an emergent caesarean section. There was no fetal mortality, although three newborns (43%) required admission to the neonatal intensive care unit. Two patients were initiated on medication-assisted treatment for opioid use disorder. Consultants included infectious disease, cardiology, cardiac surgery, maternal-fetal medicine, and psychiatry.
Conclusion These findings confirm that IVDA is a growing risk factor for pregnancy-related IE. Peripartum IE carries a high risk of complications, including maternal mortality, and warrants management with a multidisciplinary care team at a tertiary center.
Key Points
Pregnant Populations which Benefit from Vaginal Progesterone for Preventing Preterm Birth at <34 Weeks and Neonatal Morbidities: A Systematic Review and Meta-analysis
Authors: Lin Xiaobin , Nie Yu 
Published: June 2022

This study aimed to assess vaginal progesterone's effect on different populations and performed comparation between women with varied risk factors. Embase, PubMed, Cochrane library (CENTRAL) were searched without restriction to language up to February 25, 2021. Randomized controlled trials (RCTs) assessing vaginal progesterone administered to women at risk of preterm birth at <37 weeks. Two reviewers independently extracted data, and pooled relative risk (RR) with 95% confidence intervals (CIs) was calculated as well. Women with short cervix have a significantly lower risk of preterm birth at <34 weeks (pooled RR = 0.65; 95% CI: 0.55–0.77; I
2 = 0; p < 0.001; nine studies) and some neonatal morbidities; interaction tests showed that effect of vaginal progesterone differs significantly between women with short cervix and those with other risk factors (history of preterm birth, exclusive twin gestation, and vaginal bleeding). Evidences of this study showed that singleton gestations, as well as women with short cervix, benefit from vaginal progesterone in preventing preterm birth at <34 weeks and some neonatal morbidities. Women with short cervix are populations who benefit the most among other risk populations.
Key Points
DLK1: A Novel Biomarker of Placental Insufficiency in Stillbirth and Live Birth
Authors: Page Jessica M. , Allshouse Amanda A. , Gaffney Jessica E. , Roberts Victoria H. J. , Thorsten Vanessa , Gibbins Karen J. , Dudley Donald J. , Saade George , Goldenberg Robert L. , Stoll Barbara J. , Hogue Carol J. , Bukowski Radek , Parker Corette , Conway Deborah , Reddy Uma M. , Varner Michael W. , Frias Antonio E. , Silver Robert M. 
Published: June 2022

Objective Delta-like homolog 1 (DLK1) is a growth factor that is reduced in maternal sera in pregnancies with small for gestational age neonates. We sought to determine if DLK1 is associated with stillbirth (SB), with and without placental insufficiency.
Study Design A nested case-control study was performed using maternal sera from a multicenter case-control study of SB and live birth (LB). SB and LB were stratified as placental insufficiency cases (small for gestational age <5% or circulatory lesions on placental histopathology) or normal placenta controls (appropriate for gestational age and no circulatory lesions). Enzyme-linked immunosorbent assay (ELISA) was used to measure DLK1. The mean difference in DLK1 was compared on the log scale in an adjusted linear regression model with pairwise differences, stratified by term/preterm deliveries among DLK1 results in the quantifiable range. In exploratory analysis, geometric means were compared among all data and the proportion of “low DLK1” (less than the median value for gestational age) was compared between groups and modeled using linear and logistic regression, respectively.
Results Overall, 234 SB and 234 LB were analyzed; 246 DLK1 values were quantifiable within the standard curve. Pairwise comparisons of case and control DLK1 geometric means showed no significant differences between groups. In exploratory analysis of all data, adjusted analysis revealed a significant difference for the LB comparison only (SB: 71.9 vs. 99.1 pg/mL, p = 0.097; LB: 37.6 vs. 98.1 pg/mL, p = 0.005). In exploratory analysis of “low DLK1,” there was a significant difference between the odds ratio of having “low DLK1” between preterm cases and controls for both SB and LB. There were no significant differences in geometric means nor “low DLK1” between SB and LB.
Conclusion In exploratory analysis, more placental insufficiency cases in preterm SB and LB had “low DLK1.” However, low DLK1 levels were not associated with SB.
Key Points
Adverse Pregnancy Outcomes in Nondiabetic Patients with an Elevated Early Pregnancy HbA1c
Authors: Bender Whitney R. , McCarthy Clare , Elovitz Michal , Parry Samuel , Durnwald Celeste 
Published: June 2022

Objective This study aimed to evaluate the impact of elevated early hemoglobin A1c (HbA1c) values on perinatal outcomes in patients without a diagnosis of diabetes or gestational diabetes.
Study Design This is a retrospective study of patients with a singleton pregnancy who underwent universal HbA1c screening in early pregnancy at an urban tertiary care center between December 1, 2016, and December 31, 2018. Patients with pregestational diabetes mellitus (DM) and gestational DM (GDM) were excluded from analysis. The exposure of interest was HbA1c of 5.7 to 6.4% as measured on routine prenatal bloodwork at or during 16 weeks' gestation. The following pregnancy outcomes were assessed: preterm delivery <37 weeks, hypertensive disorders of pregnancy, shoulder dystocia, macrosomia (birth weight >4,000 g), small or large for gestational age neonate, operative vaginal delivery, third- or fourth-degree lacerations, cesarean delivery, neonatal intensive care unit (NICU) admission, neonatal hypoglycemia, and neonatal hyperbilirubinemia. Multivariable regression was performed to assess the relationship between HbA1c and selected adverse outcomes while controlling for potential confounders
Results Of the 2,621 patients who met inclusion criteria, 334 (12.7%) had an elevated HbA1c of 5.7 to 6.4%. Patients with an elevated HbA1c were more likely to be older, Black, multiparous, publically insured, obese, or have chronic hypertension than patients with normal HbA1c values. In the unadjusted analysis, patients with an elevated HbA1c were less likely to deliver at term (84.7 vs. 92.4%, p = 0.006), but more likely to undergo cesarean section (32.8 vs. 27.6%, p = 0.038), develop hypertensive disorders of pregnancy (31.9 vs. 23.2%, p = 0.001), or deliver a macrosomic infant (10.5 vs. 6.8%, p = 0.016) than those with a normal A1c. After adjusting for race, body mass index, insurance status, nulliparity, and age, however, only the relationship between HbA1c and spontaneous preterm birth remained significant (adjusted odds ratio [aOR] = 1.76, 95% confidence interval [CI]: 1.01–3.07).
Conclusion In our urban population, an elevated early HbA1c was associated with spontaneous preterm birth in nondiabetic patients
Key Points
Facelift Techniques: An Overview
Authors: Kaya Kerem Sami , Cakmak Ozcan 
Published: June 2022

AbstractFacelift techniques can be classified according to the depth and extent of the dissection applied. Imbrication and plication of the superficial musculoaponeurotic system (SMAS) referred to as “SMAS lifts” or “classical facelifts” are the most commonly used techniques. Plication techniques involve in-folding of the SMAS and suture suspension without any SMAS incision whereas imbrication techniques involve a SMAS incision with a portion of the SMAS either removed or transposed with or without limited sub-SMAS dissection. Aging changes in the lower face and neck can be successfully treated with SMAS lift techniques. However, there is no lifting effect at midface level or improvement in the nasolabial folds since the retaining (zygomatic cutaneous and masseteric cutaneous) ligaments that prevent the transmission of traction to the malar portion of the facelift dissection are not released. Extended facelift techniques involve surgical release of these ligaments, and produce combined, balanced, and harmonious rejuvenation of the midface, cheek, and lower face without requiring a separate midface lift procedure. There are different techniques having similar extended midface dissections with some variations: The extended SMAS technique involves a long skin flap and a distinct SMAS flap dissected and pulled separately. The high SMAS technique has a similar dissection but involves a higher SMAS flap along the superior border of the zygomatic arch. The deep plane facelift involves undermining of skin-SMAS flap as a single unit following a more limited subcutaneous dissection. In the composite plane facelift, in addition to deep plane facelift dissection, the lower part of the orbicularis oculi muscle is also dissected and included in the flap. As they have a single unit, deep and composite flap facelifts allow excellent blood supply to the overlying skin. In this article, various facelift techniques are discussed in detail in line with the relevant surgical anatomy.
Predicting Progression from Gestational Diabetes to Impaired Glucose Tolerance Using Peridelivery Data: An Observational Study
Authors: Bengtson Angela M. , Dice Ana Lucia Espinosa , Clark Melissa A. , Gutman Roee , Rouse Dwight , Werner Erika 
Published: June 2022

Objective This article aimed to develop a predictive model to identify persons with recent gestational diabetes mellitus (GDM) most likely to progress to impaired glucose tolerance postpartum.
Study Design We conducted an observational study among persons with GDM in their most recent pregnancy, defined by Carpenter-Coustan criteria. Participants were followed up from delivery through 1-year postpartum. We used lasso regression with k-fold cross validation to develop a multivariable model to predict progression to impaired glucose tolerance, defined as HbA1c≥5.7%, at 1-year postpartum. Predictive ability was assessed by the area under the curve (AUC), sensitivity, specificity, and positive and negative predictive values (PPV and NPV).
Results Of 203 participants, 71 (35%) had impaired glucose tolerance at 1-year postpartum. The final model had an AUC of 0.79 (95% confidence interval [CI]: 0.72, 0.85) and included eight indicators of weight, body mass index, family history of type 2 diabetes, GDM in a prior pregnancy, GDM diagnosis<24 weeks' gestation, and fasting and 2-hour plasma glucose at 2 days postpartum. A cutoff point of ≥ 0.25 predicted probability had sensitivity of 80% (95% CI: 69, 89), specificity of 58% (95% CI: 49, 67), PPV of 51% (95% CI: 41, 61), and NPV of 85% (95% CI: 76, 91) to identify women with impaired glucose tolerance at 1-year postpartum.
Conclusion Our predictive model had reasonable ability to predict impaired glucose tolerance around delivery for persons with recent GDM.
Key Points
Identification of Distinct Risk Factors for Antepartum and Postpartum Preeclampsia in a High-Risk Safety-Net Hospital
Authors: Picon Michelle , Stanhope Kaitlyn K. , Jamieson Denise J. , Boulet Sheree L. 
Published: June 2022

Objective Postpartum preeclampsia (PE), defined as de novo PE that develops at least 48 hours following delivery, can be particularly dangerous as many patients are already discharged at that point. The goal of our study was to identify risk factors uniquely associated with the development of late postpartum preeclampsia (PPPE).
Study Design In a retrospective cohort study of deliveries between July 1, 2016 and June 30, 2018 at a safety-net hospital in Atlanta, Georgia, we used multinomial logistic regression models to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for associations between demographic, medical, and obstetric factors and development of PE, categorized as a three-level outcome: no PE, antepartum/intrapartum preeclampsia (APE) (diagnosed prior to or < 48 hours of delivery), and late PPPE (diagnosed ≥ 48-hour postpartum).
Results Among 3,681 deliveries, women were primarily of ages 20 to 35 years (76.4%), identified as non-Hispanic Black (68.5%), and covered by public health insurance (88.6%). PE was diagnosed prior to delivery or within 48-hour postpartum in 12% (n = 477) of the study population, and 1.5% (57) developed PE greater than 48-hour postpartum. In the adjusted models, maternal age ≥ 35, race/ethnicity, nulliparity, a diagnosis of pregestational or gestational diabetes, and chronic hypertension were associated with increased odds of APE only, while maternal obesity (OR: 1.9; 95% CI: 1.0–3.5) and gestational hypertension (OR: 2.7; 95% CI: 1.5–4.8) were uniquely associated with PPPE. Multifetal gestations and cesarean delivery predicted both PPPE and APE; however, the association was stronger for PPPE.
Conclusion Patients with obesity, gestational hypertension, multifetal gestations, or cesarean delivery may benefit from additional follow-up in the early postpartum period to detect PPPE.
Key Points
Incidence of Gestational Diabetes Diagnosed on the 100-G Glucose Tolerance Test in Pregnancies with a 50-G Glucose Challenge Test Result of 200 mg/dL or Greater
Authors: Lord Megan G. , Agee Robert L. , Sood Nikki , Clark Melissa , Johnson Isaiah M. 
Published: June 2022

Objective This study aimed to assess the positive predictive value (PPV) of a 1-hour, 50-g glucose challenge test (GCT) result ≥200 mg/dL for the diagnosis of gestational diabetes mellitus (GDM) on a 3-hour, 100-g glucose tolerance test (GTT).
Study Design Pregnancies between 2008 and 2016 with a GCT result ≥200 mg/dL were identified retrospectively. GCT and GTT dates and results, demographics, and working due date (EDD) were extracted. Gestational age at testing was calculated from test date and EDD. As some clinicians presumptively diagnose GDM in such cases, if a GTT result was not available, clinic notes were reviewed to determine whether a GTT was ordered. Positive predictive values (PPV) were calculated at GCT cut-offs at and beyond 200 mg/dL. Subgroups were compared including early GCT (<16 weeks) versus routine GCT (24–28 weeks), GTT result normal versus GTT diagnostic of GDM, and GTT ordered versus GTT not ordered. Rates of use of medication for glycemic control were assessed among these groups.
Results Of 236 pregnant women with a GCT result ≥200 mg/dL, 115 (48%) GTT was ordered for 115 (49%), whereas 123 (52%) were managed as presumed GDM. Of 100 (87%) who completed the test, 81 (81%) were diagnosed with GDM with a median intertest interval of 14 days. No statistically significant differences were found between groups stratified by GTT result. Use of rates of metformin, glyburide, and insulin were similar between those diagnosed with GDM by GTT and those diagnosed with GDM by GCT alone.
Conclusion A GCT result of ≥200 mg/dL has a PPV of 81% for diagnosis of GDM by GTT in a contemporary U.S. population, with a median intertest interval of 14 days between GCT and GTT. However, those diagnosed by GCT alone were as likely as those diagnosed by GTT to require medication for glycemic control, including insulin, suggesting that requiring a GTT may result in underdiagnosis and delayed treatment of GDM.
Key Points
Population-Level Study on Fetal Deaths and Preterm Births during SARS-CoV-2 Pandemic in the State of Michigan
Authors: Bajaj Monika , Romero Roberto , Myers Lindsey , Duncan Jeffrey , Yeo Lami , Jani Sanket , Natarajan Girija 
Published: June 2022

Objective The aim of the study is to explore the effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic on preterm birth at different gestational ages and fetal death in the state of Michigan.
Study Design Data on live births and fetal deaths in the state of Michigan from March to November in the years 2017 through 2020 were obtained from Michigan Department of Health and Human Services (MDHHS). Preterm birth rate, fetal death rate (per 1,000 live births) overall and stratified by race and maternal comorbidities during the period of pandemic (March–November 2020) were compared with the same period (March–November) in the prepandemic years (2017–2019).
Results Of 328,879 live births and 1,470 fetal deaths during the study period, 77,983 live births and 242 fetal deaths were reported in 2020. Compared with prepandemic years, fetal death rate per 1,000 live births was significantly lower in 2020 (3.1 vs. 4.7 [2017], 5.2 [2018], 4.4 [2019], p-value <0.001). The adjusted risk for fetal death in 2020 was decreased (odds ratio [OR] = 0.64 [95% confidence interval (CI): 0.56–0.74], p <0.0001), compared with prepandemic years. Fetal death was significantly associated with African-American race, pregnancy hypertension and prepregnancy diabetes. No significant difference in the proportion of preterm births (<37 weeks' gestation) was noted between pandemic and prepandemic years (9.9 vs. 10.0%, p = 0.50). There was no significant difference in the risk of preterm birth across gestational age strata (<28, 28–316/7, 32–366/7, 37–416/7, and >42 weeks) between pandemic and prepandemic years on multinomial analysis. Significant associations with preterm birth across all years included African American race, lower level of maternal education, pregnancy-induced hypertension, chronic hypertension, prepregnancy diabetes, congenital anomalies, previous preterm birth, and prolonged rupture of membranes >12 hours.
Conclusion Fetal death rate was significantly lower whereas preterm births remained unchanged during pandemic in comparison with prepandemic years in the state of Michigan.
Key Points
A trace inequality of Ando, Hiai, and Okubo and a monotonicity property of the Golden–Thompson inequality
Authors: Carlen Eric A. , Lieb Elliott H. 
Published: June 2022

The Golden–Thompson trace inequality, which states that Tr eH+K ≤ Tr eHeK, has proved to be very useful in quantum statistical mechanics. Golden used it to show that the classical free energy is less than the quantum one. Here, we make this G–T inequality more explicit by proving that for some operators, notably the operators of interest in quantum mechanics, H = Δ or H=−−Δ+m and K = potential, Tr eH+(1−u)KeuK is a monotone increasing function of the parameter u for 0 ≤ u ≤ 1. Our proof utilizes an inequality of Ando, Hiai, and Okubo (AHO): Tr XsYtX1−sY1−t ≤ Tr XY for positive operators X, Y and for 12≤s,t≤1, and s+t≤32. The obvious conjecture that this inequality should hold up to s + t ≤ 1 was proved false by Plevnik [Indian J. Pure Appl. Math. 47, 491–500 (2016)]. We give a different proof of AHO and also give more counterexamples in the 32,1 range. More importantly, we show that the inequality conjectured in AHO does indeed hold in the full range if X, Y have a certain positivity property—one that does hold for quantum mechanical operators, thus enabling us to prove our G–T monotonicity theorem.