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Polaritons are light-matter quasiparticles that govern the optical response of quantum materials at the nanoscale, enabling on-chip communication and local sensing. Here, we report Landau-phonon polaritons (LPPs) in magnetized charge-neutral graphene encapsulated in hexagonal boron nitride (hBN). These quasiparticles emerge from the interaction of Dirac magnetoexciton modes in graphene with the hyperbolic phonon polariton modes in hBN. Using infrared magneto-nanoscopy, we reveal the ability to completely halt the LPP propagation in real space at quantized magnetic fields, defying the conventional optical selection rules. The LPP-based nanoscopy also tells apart two fundamental many-body phenomena: the Fermi velocity renormalization and field-dependent magnetoexciton binding energies. Our results highlight the potential of magnetically tuned Dirac heterostructures for precise nanoscale control and sensing of light-matter interaction.

Magnetic fields can have profound effects on the motion of electrons in quantum materials. Two-dimensional electron systems subject to strong magnetic fields are expected to exhibit quantized Hall conductivity, chiral edge currents and distinctive collective modes referred to as magnetoplasmons and magnetoexcitons. Generating these propagating collective modes in charge-neutral samples and imaging them at their native nanometre length scales have thus far been experimentally elusive. Here we visualize propagating magnetoexciton polaritons at their native length scales and report their magnetic-field-tunable dispersion in near-charge-neutral graphene. Imaging these collective modes and their associated nano-electro-optical responses allows us to identify polariton-modulated optical and photo-thermal electric effects at the sample edges, which are the most pronounced near charge neutrality. Our work is enabled by innovations in cryogenic near-field optical microscopy techniques that allow for the nano-imaging of the near-field responses of two-dimensional materials under magnetic fields up to 7 T. This nano-magneto-optics approach allows us to explore and manipulate magnetopolaritons in specimens with low carrier doping via harnessing high magnetic fields.

FeSe1-xSx remains one of the most enigmatic systems of Fe-based superconductors. While much is known about the orthorhombic parent compound, FeSe, the tetragonal samples, FeSe1-xSx with x > 0.17, remain relatively unexplored. Here, we provide an in-depth investigation of the electronic states of tetragonal FeSe0.81S0.19, using scanning tunneling microscopy and spectroscopy (STM/S) measurements, supported by angle-resolved photoemission spectroscopy (ARPES) and theoretical modeling. We analyze modulations of the local density of states (LDOS) near and away from Fe vacancy defects separately and identify quasiparticle interference (QPI) signals originating from multiple regions of the Brillouin zone, including the bands at the zone corners. We also observe that QPI signals coexist with a much stronger LDOS modulation for states near the Fermi level whose period is independent of energy. Our measurements further reveal that this strong pattern appears in the STS measurements as short range stripe patterns that are locally two-fold symmetric. Since these stripe patterns coexist with four-fold symmetric QPI around Fe-vacancies, the origin of their local two-fold symmetry must be distinct from that of nematic states in orthorhombic samples. We explore several aspects related to the stripes, such as the role of S and Fe-vacancy defects, and whether they can be explained by QPI. We consider the possibility that the observed stripe patterns may represent incipient charge order correlations, similar to those observed in the cuprates.

IntroductionUrethral multiplicity is a rare congenital anomaly characterized by the presence of two or more urethral channels. It is more common in males and can cause double urinary stream, incontinence, obstruction, and recurrent urinary infections. Diagnosis is difficult due to diverse clinical manifestations. Implementing an evidence-based treatment plan is challenging due to the need for more concise and informative summary publications. Our paper provides a comprehensive review of the management of this pathology and might serve as a valuable resource for pediatric urologists and specialists in the field.MethodsA comprehensive search in four electronic databases, PubMed®, PubMed Central® (PMC), Scopus, and Clarivate Analytics's Web of Science (WoS), was conducted to identify case reports and series published between 2008 and 2023 on urethral multiplicities. The quality of the articles was assessed using qualified instruments. Covidence® tool-guided synthesis was followed by individual patient data extraction. Further classifications and analysis were made using Microsoft Excel®.ResultsOut of the 90 papers included in the review, 62 were case presentations, and 28 were case series. We found 250 boys with urethral multiplicity. Based on Effman's classification, there were 38 cases of type I (15.3%), 21 type IIA1 (8.4%), 55 type IIA2 (22.1%), 91 type IIA2Y (36.5%), 4 type IIB (1.6%), and 6 type III (2.4%) urethral duplications. There were 19 cases of prepubic sinuses (7.6%), 9 triplications (3.6%), and 6 unknown forms (2.4%). We have provided data for each type, including clinical presentation, investigations, surgical management, and outcomes.ConclusionsUrethral multiplicities are a rare and varied group of malformations that require high-quality imaging examination for successful management. Treatment is specific to each patient and may depend on the surgeon's preference or skill.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?ID = CRD42023471685, identifier (CRD42023471685).

Abstract FeSe1−x S x remains one of the most enigmatic systems of Fe-based superconductors. While much is known about the orthorhombic parent compound, FeSe, the tetragonal samples, FeSe1−x S x with x > 0.17, remain relatively unexplored. Here, we provide an in-depth investigation of the electronic states of tetragonal FeSe0.81S0.19, using scanning tunneling microscopy and spectroscopy (STM/S) measurements, supported by angle-resolved photoemission spectroscopy (ARPES) and theoretical modeling. We analyze modulations of the local density of states (LDOS) near and away from Fe vacancy defects separately and identify quasiparticle interference (QPI) signals originating from multiple regions of the Brillouin zone, including the bands at the zone corners. We also observe that QPI signals coexist with a much stronger LDOS modulation for states near the Fermi level whose period is independent of energy. Our measurements further reveal that this strong pattern appears in the STS measurements as short range stripe patterns that are locally two-fold symmetric. Since these stripe patterns coexist with four-fold symmetric QPI around Fe-vacancies, the origin of their local two-fold symmetry must be distinct from that of nematic states in orthorhombic samples. We explore several aspects related to the stripes, such as the role of S and Fe-vacancy defects, and whether they can be explained by QPI. We consider the possibility that the observed stripe patterns may represent incipient charge order correlations, similar to those observed in the cuprates.

IntroductionAssessment of myocardial function through speckle tracking echocardiography (STE) can bring benefits to conventional echocardiography in premature newborns, a particular vulnerable group in terms of adaptation to extra-uterine life. Furthermore, it represents a non-invasive imagistic method which can guide therapeutic approach in the hemodynamically unstable newborn. This study aims to highlight the particularities of myocardial function in late premature newborns, by conducting a comparison with a group of healthy neonates, by using STE.MethodsConducted over a timespan of two years, this prospective study enrolled 64 term neonates and 21 premature newborns, with gestational ages ranging between 28 and 36 weeks, who prior to discharge underwent a cardiac ultrasound, involving two-dimensional image acquisitions of the apical four-chamber view of both ventricles. Afterwards, the images were offline analyzed, by using the autostrain function.ResultsAfter segmental strain analysis, no significant discrepancies between the two groups in terms of interventricular values were found. However, left ventricle and right ventricle strain measurements differed significantly (p

The La-based "214"cuprates host several symmetry-breaking phases, including superconductivity, charge and spin order in the form of stripes, and a structural orthorhombic-to-tetragonal phase transition. Therefore these materials are an ideal system to study the effects of uniaxial stress onto the various correlations that pervade the cuprate phase diagram. We report resonant x-ray scattering experiments on La1.475Nd0.4Sr0.125CuO4(LNSCO-125) that reveal a significant response of charge stripes to uniaxial tensile stress of ∼0.1GPa. These effects include a reduction of the onset temperature of stripes by ∼50K, a 29-K reduction of the low-temperature orthorhombic-to-tetragonal transition, competition between charge order and superconductivity, and a preference for stripes to form along the direction of applied stress. Altogether, we observe a dramatic response of the electronic properties of LNSCO-125 to a modest amount of uniaxial stress.

We present the case of a neonatal patient with atrial tachycardia with unusual characteristics – abrupt onset and cessation, non-responsiveness to overdrive, termination by direct cardio-version – in association with an ostium secundum-type atrial septal defect and a large inter-atrial septum aneurysm. Electrocardiographic recordings showed P waves with characteristics suggesting a right low septal origin, which suggested a possible involvement of the septal aneurysm. In dealing with arrhythmias, a thorough echocardiographic evaluation is mandatory to identify underlying structural malformations and to evaluate the hemodynamic status. Further research should be made concerning mechanisms of arrhythmias in patients with an associated atrial septum aneurysm.

El presente estudio tiene como finalidad determinar las propiedades físicas y mecánicas del hormigón con virutas de acero de grado ASTM A36, y realizar un estudio comparativo con el hormigón tradicional. Se tuvo como muestra 36 probetas y se utilizó la viruta de acero en 0,6%, 1,5 y 6% como agregado fino. La viruta se obtuvo de los tornos de la empresa SMF Sagitario en la Ciudad de Lima. El diseño de la investigación es cuasi experimental y de corte longitudinal, la técnica de recolección de datos fue la observación. Se utilizó la estadística inferencial para la constatación de hipótesis, donde los resultados indicaron que hay diferencias significativas entre el hormigón tradicional y el hormigón con agregado fino (Sig.=.000). Concluyéndose que el hormigón tradicional es superior a en resistencia a la compresión y tracción realizadas a los 7, 14 y 28 días de edad

Introduction. Coarctation of the aorta (CoA) occurs in 6-8% of patients with congenital heart disease, with an incidence of 4/10,000 live births. It can be present with various clinical pictures, in an age range between newborn and adolescence. Infants with birth weights ≤ 2 kg with CoA have increased risk of severe intraventricular hemorrhage (IVH) compared to their birth weight-matched cohorts. Case presentation. We present a case of a premature, male newborn, with low birth weight, who at the age of 3 weeks developed signs and symptoms of cardiogenic shock. Clinical examination, echocardiography and angio-CT confirmed the diagnosis of a severe CoA, without any flow through the ductus arteriosus. Treatment with prostaglandin E1 was initiated, to promote ductal patency. The systolic blood pressures were above 99 percentile for his gestational age in the upper extremities, with a noninvasive pressure gradient around 86 mmHg between the arm and leg. Transfontanellar ultrasonography evaluation revealed a grade II/III bilateral IVH, in resorption, with cystic transformation. At the age of 6 weeks definitive surgical repair was performed. Postoperatively, at the 3 month follow-up, the clinical suspicion of recoarctation of the aorta arose, confirmed by echocardiography and angio-CT, with arterial hypertension and gradient around 37 mmHg between the arm and leg. Prosthetic patch aortoplasty was performed. The postoperative evolution was marked by the persistence of arterial hypertension, the infant requiring continued treatment with angiotensin-converting enzyme inhibitor. Conclusions. Premature neonates with low birth weight have always constituted a medical management challenge, with short and long term implications. A strong point in solving such cases is a multidisciplinary medical for assessment, management and outcomes.

Circulating biomarkers have been proposed for early identification of aortic dilatation progression associated with bicuspid aortic valve (BAV), but matrix metalloproteinases (MMPs) are distinguished as signatures of increased extracellular matrix degradation, a landmark of aneurysm formation. The current study aims to identify the role of MMP-1, MMP-2, MMP-9, and the MMP inhibitor, TIMP-1, in identifying aortic dilation in children with BAV. We conducted a study on 73 children divided into two study groups, depending on the presence of aortic dilatation (group 1–43 BAV controls and group 2–30 children with BAV and aortic dilatation). Each patient underwent a cardiac ultrasound and, in each case, serum MMP-1, MMP-2, MMP-9, and TIMP-1 were quantified using xMAP technology. Comparison of the MMPs between the two study groups revealed significantly higher values only in the case of TIMP-1, among BAV controls. Moreover, the same TIMP-1 inversely correlated with aortic annulus absolute size and z score, as well as with ascending aorta z score. No particular correlation between the aortic phenotype and the presence of aortic dilatation was found. Future longitudinal research starting at pediatric ages could show the significance of MMPs screening in BAV individuals as predictors of aortic aneurysm formation. [ABSTRACT FROM AUTHOR]

IntroductionGeneralized arterial calcification of infancy (GACI) is a rare cause of infantile heart failure and systemic hypertension with a poor prognosis, characterized by extensive calcification and proliferation of the intimal layer of large and medium sized arteries.Case reportWe present the first case report of successful surgical treatment of severe aortic arch obstruction by calcified plaques mimicking severe coarctation of the aorta and the outcome (of bisphosphonate therapy) in a newborn with GACI. Furthermore, we report the identification of a variant in ATP Binding Cassette Subfamily C, Member 6 (ABCC6) gene, possibly associated with severe early-onset manifestations of GACI.ConclusionThis case report highlights the importance of considering GACI in an infant with heart failure, systemic hypertension, and evidence of increased echogenicity of the arterial vessels. We noted the favorable outcome in improving the aortic calcification in our patient after surgical treatment and bisphosphonates therapy. Early diagnosis and treatment improve the long-term prognosis. A better understanding of this rare genetic disease could lead to new therapeutic strategies.

Background: Raghib syndrome is a rare malformation complex consisting of the drainage of the left superior vena cava (LSVC) into the left atrium, ostial atresia of the coronary sinus and an atrial septal defect (ASD). Case Report: This report aims to present the case of a child newly diagnosed with Raghib syndrome, complicated by pulmonary arterial hypertension, and to review previously published cases with the same diagnosis. A six-year-old female patient presented with signs and symptoms of heart failure (Ross III), reduced exercise tolerance and severe delay in stature and ponderal development. The imagistic work-up included echocardiography, followed by computer tomography (CT) and magnetic resonance imaging (MRI), through which a diagnosis of Raghib syndrome was established, complicated by pulmonary hypertension. As in other cases presented in the literature, MRI allowed for an accurate diagnosis, detecting the absent coronary sinus. The decision regarding the surgical closure of the ASD was made, with the patient having a favorable clinical evolution but with the persistence of elevated pulmonary artery pressure, for which Sildenafil therapy was instituted. Conclusions: The malformation complex consisting of an atrial septal defect, ostium atresia of the coronary sinus, uncovered coronary sinus, and persistent left superior vena cava, as identified through multiple imagistic investigations, was suggestive of the rare diagnosis of Raghib syndrome in this case. Among the limited number of cases of Raghib syndrome available in the literature, the present case is distinguished by the severity of the pulmonary artery hypertension at a very young age and in the absence of other concurrent cardiac malformations. [ABSTRACT FROM AUTHOR]

Turner syndrome (TS) is the most common chromosomal abnormality affecting females and cardiac abnormalities have been described in up to 50% of patients. Although coarctation represents one of the most frequent cardiac malformation, treatment options in these patients represent an area of debate, due to associated aortopathy and risk for aortic dissection. In addition to the contradictory data found in the literature, regarding the safety profile and utility of stenting of coarctation of the aorta in TS patients, we present the case of a patient of pediatric age, who successfully underwent the procedure, being free from periprocedural and short-term complications. Beside the presentation itself, we aimed to review and summarize the data available in the literature regarding this topic. As a conclusion, we emphasise the role of minimally invasive interventional therapy and wish to underline the need of further, larger scale studies and guidelines in this patient group. Given the related aortopathy, all preventive measures should be undertaken to avoid aortic dissection during stent implantation in this vulnerable population. Although the evolution of our patient was favorable, data found in the literature is somewhat contradictory and a close follow-up is indicated to help evaluate the risk of long-term complications.

Implementation of a quarterly multidisciplinary neonatal transitional care (NTC) study day to ensure all staff working in postnatal clinical environments have specific NTC training that is jointly designed and delivered by the paediatric doctors, neonatal nurses, midwives and maternity support workers. [ABSTRACT FROM AUTHOR]

Pediatric heart failure is a significant challenge in clinical practice, a global burden worldwide. Compared to adult population, heart failure in children has a variety of etiologies depending on the patients age. However, pediatric heart failure guidelines are still extrapolated from adult population. In infants and children, the pharmacological treatment is based on angiotensin-converting enzyme inhibitors, beta-blockers, aldosterone receptors antagonists, and other diuretics in the presence of congestion, with a lower use of device therapy. In end-stage heart failure, as a bridge to transplantation or recovery, ventricular assist devices or different palliative surgical interventions are used nowadays.This review focuses on the most important causes, pathophysiological mechanisms, clinical manifestation and management of pediatric heart faliure based on recent guidelines. Furthermore, it emphasize the newer pharmaco-logical or non-pharmacological therapies that have been recently approved in pediatric population.

Insuficiența cardiacă pediatrică reprezintă o provocare în practica clinică și o povară la nivel mondial. În comparație cu populația adultă, etiologia insuficienței cardiace la copii este dependentă de vârsta pacienților. Cu toate acestea, ghidurile referitoare la insuficiența cardiacă pediatrică sunt extrapolate din ghidurile pentru adulți. În cazul sugarilor și al copiilor, tratamentul farmacologic este bazat pe inhibitori de enzimă de conversie, betablocante, antagoniști ai receptorilor de aldosteron și alte diuretice (în prezența congestiei). În insuficiența cardiacă terminală, dispozitivele de asistare ventriculară sau diferite intervenții chirurgicale paliative sunt utilizate ca o punte pentru transplant sau recuperare. Prezenta lucrare se concentrează pe cele mai importante cauze, mecanisme fiziopatologice, manifestări clinice și managementul în insuficiența cardiacă pediatrică, bazate pe cele mai recente ghiduri. În plus, subliniază cele mai noi tratamente farmacologice și nonfarmacologice recent aprobate pentru populația pediatrică

Scimitar syndrome is a rare congenital cardiovascular malformation that includes a partially anomalous drainage of the pulmonary veins in the inferior vena cava, right pulmonary hypoplasia, and systemic-pulmonary collaterals originating from various segments of the aorta. We present a case of Scimitar syndrome with associated intracardiac lesions and a large arterial conduct supplying the right lung, originating from the abdominal aorta and draining in the inferior vena cava.

Introduction: The incidence of cardiac arrhythmia is approximately 1% in the neonatal period and 1–3% in late pregnancy. Atrial flutter (AF), a rhythm disorder based on the mechanism of reentry, represents approximately 32% of all neonatal cardiac arrhythmias. In the majority of cases, the flutter is converted to sinus rhythm using antiarrhythmic drugs, transesophageal overdrive pacing, or synchronized electrical cardioversion.

Introducere. Coarctația de aortă (CoA) este prezentă la 6-8% dintre pacienții cu boală congenitală cardiacă, cu o incidență de 4/10.000 nou-născuți vii. Poate fi prezentă cu diferite tablouri clinice, de la vârsta de nou-născut până la adolescență. Nou-născuții cu greutate la naștere sub 2 kg și cu CoA au risc crescut de a dezvolta hemoragie intraventriculară (HIV) severă, comparativ cu cei din cohorta cu greutate normală la naștere. Prezentare de caz. Prezentăm cazul unui prematur de sex masculin, cu greutate mică la naștere, care la vârsta de 3 săptămâni dezvoltă semne și simptome de șoc cardiogen. Examenul clinic, ecocardiografia și examenul angio-CT confirmă diagnosticul de CoA severă, fără flux vizibil în canalul arterial. A fost inițiat imediat tratament cu prostaglandină E1, pentru permeabilizarea canalului arterial. Tensiunea arterială sistolică a fost peste percentila 99 pentru vârsta gestațională, iar gradientul nonivaziv între membrul superior și cel inferior a fost de circa 86 mmHg. Ecografia transfontanelară decelează hemoragie intraventriculară grad II/III, bilateral, în resorbție, cu transformare chistică. La vârsta de 6 săptămâni, sugarul a beneficiat de corecția chirurgicală a CoA. La reevaluarea de 3 luni postoperator, pe baza semnelor clinice, s-a ridicat suspiciunea de recoarctație de aortă, confirmată prin ecocardiografie și angio-CT. Pacientul prezenta hipertensiune arterială, cu diferență de tensiune între membrele superioare și cele inferioare de circa 37 mmHg. A fost realizată corecție chirurgicală, de această dată prin angioplastie de lărgire cu petec. Evoluția postoperatorie a fost grevată de prezența hipertensiunii arteriale, pentru care a necesitat tratament continuu cu inhibitor de enzimă de conversie. Concluzii. Prematurii cu greutate mică asociată cu CoA corectată chirurgical au un risc ridicat de recoarctare, hipertensiune arterială secundară și hemoragie cerebrală. Un punct important în soluționarea acestor cazuri îl reprezintă echipa medicală multidisciplinară, pentru evaluarea, managementul, dar și prognosticul pacienților.

Congenital aortic stenosis (AS) occurs in around 0.2–0.5% of newborns, and its clinical severity is quite variable. Some of the newborns with AS require urgent medical care: prostaglandin infusion, balloon aortic valvuloplasty, or surgical intervention. Despite having a severe clinical evolution in neonates, the prenatal diagnosis of congenital AS is quite low. We present the case of a fetus with critical AS, who had been prenatally diagnosed at 35 weeks of gestation, via fetal cardiac ultra-sound. The echocardiographic parameters revealed a severely depressed left ventricular systolic function, with dilated chambers, and a severe aortic stenosis. Offline speckle-tracking analysis was performed in order to aid in deciding the optimal methods and timing of delivery. Left ventricular analysis revealed a severely impaired global longitudinal strain of 2.1%, left ventricular ejection fraction 18.4%, increased LV volumes, while the right ventricular function was only mildly depressed. Therefore, the decision was to delay the premature delivery, and the fetus was born at a gestational age of 38 weeks, in a hospital with a neonatal cardiovascular surgery department. The patient had undergone surgical repair of the cardiac anomaly at 3 days after birth.

This paper presents a new control approach of trajectory tracking for quadrotor unmanned aerial vehicle (UAV) systems under external disturbances and parameter uncertainties. The integral fast terminal sliding mode control (IFTSMC) approach applying state-dependent Riccati equation (SDRE) observer is presented for this purpose. As a result, the nonlinear SDRE observer is designed to estimate the non-measurable states. Afterward, employing the estimated states of the SDRE observer, the proposed IFTSMC controller is designed for trajectory tracking of the perturbed quadrotor UAV. Besides, applying Lyapunov's stability theory, the finite-time convergence and robustness of the closed-loop UAV system are assured. Based on the numerical simulation results, the proposed controller successfully tracked various reference trajectories of quadrotor UAVs despite external disturbances and parametric uncertainty. [ABSTRACT FROM AUTHOR]

Background: Acute myocarditis, a primary inflammatory cardiac disease commonly caused by viral infection, is an important cause of morbidity and mortality in children. Data obtained from forensic studies found an incidence of 15–33% for acute myocarditis in sudden deaths in the pediatric age group. Currently, there is a lack of data regarding the incidence and factors associated with short-term outcomes in pediatric patients admitted for acute myocarditis.