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A bstract We discuss consequences of the breaking of conformal symmetry by a flat or spherical extended operator. We adapt the embedding formalism to the study of correlation functions of symmetric traceless tensors in the presence of the defect. Two-point functions of a bulk and a defect primary are fixed by conformal invariance up to a set of OPE coefficients, and we identify the allowed tensor structures. A correlator of two bulk primaries depends on two cross-ratios, and we study its conformal block decomposition in the case of external scalars. The Casimir equation in the defect channel reduces to a hypergeometric equation, while the bulk channel blocks are recursively determined in the light-cone limit. In the special case of a defect of codimension two, we map the Casimir equation in the bulk channel to the one of a four-point function without defect. Finally, we analyze the contact terms of the stress-tensor with the extended operator, and we deduce constraints on the CFT data. In two dimensions, we relate the displacement operator, which appears among the contact terms, to the reflection coefficient of a conformal interface, and we find unitarity bounds for the latter.

Atom-scale defects in semiconductors are promising building blocks for quantum devices, but our understanding of their material-dependent electronic structure, optical interactions, and dissipation mechanisms is lacking. Using picosecond resonant pulses of light, we study the coherent orbital and spin dynamics of a single nitrogen-vacancy center in diamond over time scales spanning six orders of magnitude. We develop a time-domain quantum tomography technique to precisely map the defect’s excited-state Hamiltonian and exploit the excited-state dynamics to control its ground-state spin with optical pulses alone. These techniques generalize to other optically addressable nanoscale spin systems and serve as powerful tools to characterize and control spin qubits for future applications in quantum technology.

A bstract We consider the entanglement entropy for the 2D Ising model at the conformal fixed point in the presence of interfaces. More precisely, we investigate the situation where the two subsystems are separated by a defect line that preserves conformal invariance. Using the replica trick, we compute the entanglement entropy between the two subsystems. We observe that the entropy, just like in the case without defects, shows a logarithmic scaling behavior with respect to the size of the system. Here, the prefactor of the logarithm depends on the strength of the defect encoded in the transmission coefficient. We also comment on the supersymmetric case.

Purpose – The purpose of this paper is to present a novel method for fabric defect detection. Design/methodology/approach – The method based on joint low-rank and spare matrix recovery, since patterned fabric is manufactured by a set of predefined symmetry rules, and it can be seen as the superposition of sparse defective regions and low-rank defect-free regions. A robust principal component analysis model with a noise term is designed to handle fabric images with diverse patterns robustly. The authors also estimate a defect prior and use it to guide the matrix recovery process for accurate extraction of various fabric defects. Findings – Experiments on plain and twill, dot-, box- and star-patterned fabric images with various defects demonstrate that the method is more efficient and robust than previous methods. Originality/value – The authors present a RPCA-based model for fabric defects detection, and show how to incorporate defect prior to improve the detection results. The authors also show that more robust detection and less running time can be obtained by introducing a noise term into the model.

Background. Antiretroviral (ARV) regimens during pregnancy are highly effective in preventing mother-to-child transmission of human immunodeficiency virus (HIV). Congenital heart defects (CHDs) and anomalies in cardiac function have been reported in zidovudine (ZDV)–exposed uninfected children. We explored these associations in a large observational cohort and a randomized clinical trial. Methods. Since 1986, the French Perinatal Cohort prospectively enrolled all HIV-infected women in 90 centers and collected follow-up on their children through 2 years of age. All CHDs were reviewed by a specialist blinded to exposures. Additionally, in a randomized trial (PRIMEVA ANRS 135) of 2 ARV regimens during pregnancy, 1 of which was without nucleoside reverse transcriptase inhibitors, infants had a specific follow-up including echocardiography at 1 month and 12 months. Results. Among 12 888 children included, ZDV exposure in the first trimester was significantly associated with CHD (1.5% vs 0.7%; adjusted odds ratio, 2.2 [95% confidence interval, 1.3–3.7]; P < .001). This association was significant for ventricular septal defects (1.1% vs 0.6%; P = .001) and other CHDs (0.31% vs 0.11%; P = .02). In the randomized trial, among 50 infants, girls (but not boys) exposed in utero to ZDV/lamivudine/ritonavir-boosted lopinavir (LPV/r) had a higher left ventricular shortening fraction at 1 month (40% vs 36%; P = .008), and an increased posterior wall thickness at 1 year (5.4 mm vs 4.4 mm; P = .01) than the LPV/r group. Conclusions. This study confirms a specific association between in utero exposure to ZDV and CHDs, and a longlasting postnatal myocardial remodeling in girls. A potential common mechanism, including the involvement of mitochondrial dysfunction, must be explored, and long-term consequences on cardiac function warrant specific attention. Clinical Trials Registration. NCT00424814.

Lung disease in people with cystic fibrosis (CF) is initiated by defective host defense that predisposes airways to bacterial infection. Advanced CF is characterized by a deficit in mucociliary transport (MCT), a process that traps and propels bacteria out of the lungs, but whether this deficit occurs first or is secondary to airway remodeling has been unclear. To assess MCT, we tracked movement of radiodense microdisks in airways of newborn piglets with CF. Cholinergic stimulation, which elicits mucus secretion, substantially reduced microdisk movement. Impaired MCT was not due to periciliary liquid depletion; rather, CF submucosal glands secreted mucus strands that remained tethered to gland ducts. Inhibiting anion secretion in non-CF airways replicated CF abnormalities. Thus, impaired MCT is a primary defect in CF, suggesting that submucosal glands and tethered mucus may be targets for early CF treatment.

Introduction: Reconstruction of soft tissue defect always poses a reconstructive challenge. The objective of this study was to evaluate the outcome of anterolateral thigh free flap as a versatile flap for soft tissue reconstruction.  Methods: In this prospective study carried out in the Department of Plastic Surgery of Dhaka Medical College and Hospital (DMC&H), Dhaka between July 2016 to June 2017, total thirty patients with soft tissue defect in different regions of the body underwent reconstruction of defects with anterolateral thigh free flap. Twenty (60%) patients had defect in lower extremity, seven (23%) in head and neck, two in the trunk, one in upper extremity. The flaps were raised as a standard subfascial flap in 56.67% cases, as suprafascial thin flap in 23% cases and in 20% cases it was raised along with part of vastus lateralis muscle. Results: Out of 30 cases, 73.3% flaps survived completely, 20% patients had total flap loss and 3.3% patients had partial flap loss and another 3.3% had marginal necrosis. Donor site complications were observed in four patients. Conclusions: The study concluded that anterolateral thigh free flap was found to be a reliable option to reconstruct soft tissue defects in different regions of the body with minimal donor site morbidity.          J Bangladesh Coll Phys Surg 2025; 43: 109-115

To evaluate perinatal outcomes and congenital heart defect (CHD) prognosis in a non-selected population. The population-based surveillance data used in this assessment of CHDs were based on birth defect surveillance data collected from 2010-2012 in Liuyang City, China. Infants living with CHDs were followed up for 5 years to determine their prognosis. Prevalence, prenatal diagnosis, perinatal outcomes, and total and type-specific prognosis data were assessed using SPSS 18.0. In total, 190 CHD cases were identified among the 53313 included perinatal infants (PIs), indicating a CHD prevalence of 35.64 per 10000 PIs in this non-selected population. The five most frequently identified types of CHDs were ventricular septal defects (VSDs, 38.95%), atrial septal defects (ASDs, 15.79%), cardiomegaly (7.89%), tetralogy of Fallot (TOF, 5.79%), and atrioventricular septal defects (AVSDs, 5.26%). Of the 190 CHD cases, 110 (57.89%) were diagnosed prenatally, 30 (15.79%) were diagnosed with associated malformations, and 69 (36.32%) resulted in termination of pregnancy (TOP). Moreover, 15 (7.89%) PIs died within 7 days after delivery, and 42 (22.10%) died within 1 year. In contrast, 79 (41.58%) were still alive after 5 years. When TOP cases were included, the 5-year survival rate of PIs with prenatally detected CHDs was lower than that of PIs with postnatally detected CHDs (25.45% vs. 63.75%). The CHD subtype associated with the highest rate of infant (less than 1 year old) mortality was transposition of the great arteries (100%). The subtypes associated with higher 5-year survival rates were patent ductus arteriosus (80%), ASD (63.33%), VSD (52.70%) and AVSD (50%). The rates of prenatal CHD detection and TOP were high in this study population, and the 5-year survival rate of PIs with CHDs was low. The government should strengthen efforts to educate pediatricians regarding this issue and provide financial assistance to improve the prognosis of infants living with CHDs, especially during the first year of life.

Congenital heart defects constitute the most common human birth defect, however understanding of how these disorders originate is limited by our ability to model the human heart accurately in vitro. Here we report a method to generate developmentally relevant human heart organoids by self-assembly using human pluripotent stem cells. Our procedure is fully defined, efficient, reproducible, and compatible with high-content approaches. Organoids are generated through a three-step Wnt signaling modulation strategy using chemical inhibitors and growth factors. Heart organoids are comparable to age-matched human fetal cardiac tissues at the transcriptomic, structural, and cellular level. They develop sophisticated internal chambers with well-organized multi-lineage cardiac cell types, recapitulate heart field formation and atrioventricular specification, develop a complex vasculature, and exhibit robust functional activity. We also show that our organoid platform can recreate complex metabolic disorders associated with congenital heart defects, as demonstrated by an in vitro model of pregestational diabetes-induced congenital heart defects. There is a pressing need to develop representative organ-like platforms recapitulating complex in vivo phenotypes to study human development and disease in vitro. Here the authors present a method to generate human heart organoids by self-assembly using pluripotent stem cells, compare these to age-matched fetal cardiac tissues and recreate a model of pregestational diabetes.

Coherent Fourier Scatterometry (CFS) is a scatterometry technique that has been applied for grating and nanoparticle detection. Here, it has been challenged to verify the detectability of the so-called killer defects on SiC samples for power electronic applications. It has been shown that CFS is able to precisely recognize these defects regardless of their shape or size. CFS could be considered as a possible alternative for this purpose.