Search

Introduction. Fecal incontinence of various origins still remains a complex medical and social problem that reduces both the quality of life and the chance of child’s full integration into the modern society. Antegrade enema, originally described by Malone, consists of creating an appendicostomy or neoappendicostomy of the ileum, which allows to irrigate the entire colon in order to empty the colon and rectum. As a result, children stay clean from 24 to 72 hours. Thus, surgical intervention can significantly improve the quality of life of children suffering of incontinence. Laparoscopic access minimizes surgical trauma and shortens rehabilitation period.Purpose. To analyze the obtained outcomes after treating children with laparoscopic umbilical appendicostomy.Material and methods. We report our own results obtained after performing laparoscopic umbilical appendicostomy in 3 children at the Federal Scientific and Clinical Center for Children and Adolescents, FMBA of Russia. Two children had neurological disorders of the pelvic organ; the third child suffered a severe combined injury, which led to the development of gross scarring changes in the sphincter area with a complete loss of its contractility. All children underwent laparoscopic umbilical appendicostomy. The article describes in detail all the stages of preoperative preparation and surgical intervention.Results. The duration of surgery ranged from 60 to 80 minutes. An appendicostomy intubator was left for 1 month in all cases. Hospital stay ranged from 8 to 11 days. The catamnesis was traced for 3–7 months. Therapeutic effect was assessed by children’s parents as satisfactory; the child remained clean for 12–18 hours, which contributed to socialization and significantly improved the quality of life. Conclusion. Performing laparoscopic umbilical appendicostomy is a relatively affordable technique. Our own experience has proven its effectiveness. Laparoscopic access minimizes surgical trauma, reduces rehabilitation time, and brings excellent cosmetic results. Malone surgery in children should be considered as a method of choice.

Aim: to demonstrate a child with early ileocecal resection in stenosing Crohn’s disease, taking into account the risk factors of surgical intervention. Crohn’s disease (CD) is a chronic recurrent segmental granulomatous lesion of any part of the gastrointestinal tract, with a wide range of manifestations and various phenotypes of the disease. Despite the great diagnostic and therapeutic possibilities today, there is an increase in primary and secondary resistance to therapy, largely associated with an incorrect assessment of the CD phenotype, patient management strategy. In the above observation of CD in a teenager, clinical signs of ileocecal stenosis were observed 3 months after the supposed onset of the disease, which caused a planned laparoscopic ileocecal resection with the formation of a ileo-colon anastomosis. The start of CD in adolescence, positive ASCA-status are regarded as risk factors for surgical intervention in this child. Timely diagnosis did not allow to avoid surgery. It is necessary to make individual algorithms for the management of a child with CD, taking into account the predictors of surgical intervention, complications and unfavorable course of the disease already at the time of diagnosis.

Introduction. Nephroblastoma is the third most common solid tumor in childhood, accounting for 7–8% of the total number of solid tumors in children. Currently, there is no unequivocal position of oncosurgeons regarding laparoscopic nephrectomy in patients with nephroblastomas; the cases described in the world literature are rare.Purpose. To find out the effectiveness of laparoscopic kidney resection in children with nephroblastoma.Materials and methods. The authors describe two clinical cases of laparoscopic nephrectomy in patients with nephroblastoma, including one-stage bilateral laparoscopic nephrectomy for bilateral nephroblastoma.Results. At the time of article writing, the two patients were in clinical and instrumental remission for 6 and 11 months, respectively.Conclusion. Indications for laparoscopic kidney resections in nephroblastoma: stage I, peripheral location of the tumor node with predominant extrarenal growth, response to chemotherapy, absence of the cystic component of the tumor.

The 30th Annual Congress of the International Pediatric Endosurgery Group (IPEG) was held under the theme Exploring new frontiers and innovative spaces. The Congress was held in Los Angeles, USA on June 11 and 14, 2021, in a virtual format due to the ongoing coronavirus disease-2019 pandemic. More than 600 pediatric surgeons from all regions worldwide participated in the meetings. This article provides a concise overview of the scientific and practical information presented at the forum. The Congress program included 273 scientific presentations, of which 11 were made by Russian surgeons. The priority topics covered almost all sections of pediatric surgery with a certain focus on the main directions of development of minimally invasive surgery and the consistent promotion of innovative technologies in pediatric surgery. The materials of the presented presentations contained statistical data of clinical trials, proposals for improving endosurgical techniques, and creating new surgical instruments, as well as scientific justification for the use of fundamentally new medical technologies. The scientific and practical information presented at the Congress indicates that IPEG, on a global scale, continues its progressive movement toward the search for new frontiers in improving professional skills and innovative pediatric surgery development.

We have developed a theory of parametric photon generation in the waveguides coupled to arrays of qubits with temporally modulated resonance frequencies. Such generation can be interpreted as a dynamical Casimir effect. We demonstrate numerically and analytically how the emission directionality and photon-photon correlations can be controlled by the phases of the modulation. The emission spectrum is shown to be strongly dependent on the qubit anharmonicity parameter. Single- and double-excited state resonances have been identified in the emission spectrum., Comment: 8 pages, 7 figures

Quantum correlations between distant particles remain enigmatic since the birth of quantum mechanics. Here we predict a novel kind of bound quantum state in the simplest one-dimensional setup of two interacting particles in a box. Paradoxically, two entangled particles become localized at the opposite edges of the box even though their interactions at large distance should seemingly play no role. Such states could be realized in the waveguide quantum electrodynamics platform, where an array of superconducting qubits or cold atoms is coupled to a waveguide. We demonstrate how long-range waveguide-mediated couplings enable interaction-induced quantum states separated by large distances. Similarly to Majorana fermions in the Kitaev model, such bound state of distant photons is immune to short-range interactions and could find applications in robust quantum information processing., Comment: 7 pages, 6 figures

Vortices are a hallmark of topologically nontrivial dynamics in nonlinear physics and arise in a huge variety of systems, from space and atmosphere to condensed matter and quantum gases. In optics, vortices manifest as phase twists of the electromagnetic field, commonly formed by the interaction of light and matter. Formation of vortices by effective interaction of light with itself requires strong optical nonlinearity and has therefore been confined, until now, to the classical regime. Here we report on the realization of quantum vortices resulting from a strong photon-photon interaction in a quantum nonlinear optical medium. The interaction causes faster phase accumulation for co-propagating photons. Similarly to a plate pushing water, the local phase accumulation produces a quantum vortex-antivortex pair within the two-photon wavefunction. For three photons, the formation of vortex lines and a central vortex ring attests to a genuine three-photon interaction. The wavefunction topology, governed by two- and three-photon bound states, imposes a conditional phase shift of $\pi$-per-photon, a potential resource for deterministic quantum logic operations., Comment: The first two authors contributed equally to this work

First results of the study of atmospheric aerosol samples from the Middle Urals with a time-of-flight secondary ion mass spectrometer are considered. Aerosol sampling by the aspiration method on KFBZh and AFA filters is discussed. The difficulties in carrying out mass spectrometry “directly,” that is, without preliminary sample preparation, are analyzed. The results of mass spectrometry and optical microscopy of the filter surface allow us to consider prospects of their use for sampling aerosol microparticles.

BACKGROUND Management of the patients with urachal remnants (URs) has been under discussion for a long time. The traditional approach with surgical removal of all urachal remnants, has been changed to a more conservative, which is preferred by many surgeons, especially in asymptomatic patients. AIM The purpose of this study was to optimize the treatment of patients with URs, primarily for asymptomatic children. RESULTS Our previous screening study showed that real incidence of the URs in childhood is significantly higher than it was previously stated. Based on our data and the results of literature review, we propose an algorithm for the workup and treatment of children with URs. CONCLUSION We assume that the risk of developing complications (primarily, malignancy) was previously significantly overestimated. In this regard, we recommend conservative tactics in in most asymptomatic cases.

A mathematical model of the dynamic process in the structurally nonlinear system «beam – two-parameter foundation», which arises as a result of a sudden change in the physical and mechanical properties of the foundation, leading to zeroing of its shear stiffness, is constructed in a structurally-nonlinear system «beam – two-parameter foundation» The solution of the static problem of bending of a beam supported on a Pasternak base serves as the initial condition for the problem of forced vibrations of a beam on a Winkler base that arose after the sudden formation of a defect. Solutions to static and dynamic problems are constructed by the method of initial parameters with the use of vectors of states of beam sections and matrices of the influence of initial parameters on the state of arbitrary sections. In the analysis of forced vibrations, the decomposition of the load and deflections of the initial static state into rows according to the forms of natural vibrations of the new state is used.

A model of a transport connection controlled by a transport protocol with the technology of forward error correction in the selective failure mode in the form of a discrete-time Markov chain is proposed. The model takes into account the influence of the protocol parameters, the level of errors in the communication channels, the round-trip delay and the technological parameters of forward error correction on the throughput of the transport connection. The analysis of the dependence of the advantages of the transport protocol with forward error correction over the classical transport protocol is carried out.

Electrophilic amination of methyl N-(hydroxyphenyl)carbamates and methyl N-(4-methoxyphenyl)carbamate with sodium azide in 86% polyphosphoric acid (PPA) at 55–60°C regioselectively afforded methyl N-(3-amino-2-hydroxyphenyl)-, N-(4-amino-3-hydroxyphenyl)-, N-(3-amino-4-hydroxyphenyl)-, and N-(3-amino-4-methoxyphenyl)carbamates, i.e., the amino group entered the ortho position with respect to the hydroxy or methoxy group. The reactions of methyl N-(4-methoxyphenyl)carbamate with nitromethane and nitroethane in 80% PPA at 95–110°C gave methyl N-(3-carbamoyl-4-methoxyphenyl)carbamate and methyl N-(3-acetamido-4-methoxyphenyl)carbamate, respectively. Methyl N-[4-(N′-hydroxyethanimidamido)phenyl]carbamate was obtained by reaction of 4-[(methoxycarbonyl)amino]benzoic acid with excess nitroethane in 86% PPA at 125°C.

Recent years have seen a tremendous interest to atomically thin membranes such as graphene or monolayers of transition metal dichalcogenides. Owing to their light mass and strong optical resonances...

—Long-term observations (1968–2019) on the dynamics of infection by the cestode Eubothrium rugosum in the burbot (Lota lota) have been performed in the Rybinsk Reservoir on the Upper Volga. The results show that a significant and consistent decrease in the prevalence of infection has occurred in the mid-to-late 1990s and is related to global warming. Because of rise in water temperature, large zones of oxygen depletion in the bottom water layer have been formed in the reservoir, leading to mass mortality of the intermediate hosts of the cestode (ruffe and copepods). This has sharply reduced the probability of transmission of its larvae to the final host (burbot). The predicted further climate warming with abnormally hot summers may provide for further decrease in the prevalence of E. rugosum infection in the burbot.

Objective: to analyze cosmetic results following reconstruction of nasal alar defects using cheek skin flaps. Material and methods. The results of 29 operations were analyzed. The reconstruction was performed with nasolabial flaps and jigsaw puzzle flaps. The cosmetic outcomes were evaluated by the five-point scale by means of patient-report and specialist-report questionnaire. Results. Acceptable overall outcomes were achieved in 22 cases according to the experts’ assessment and in 24 cases according to the patients’ assessment. The highest scores were noted for alar color and position, and the lowest scores - for alar size, shape, and nostril size. The complication rate was 11.1 %. Delayed surgical corrections were undertaken in 10 patients. Conclusion. The reconstruction of full thickness nasal alar defects using cheek skin flaps made it possible to achieve acceptable outcomes with minimal donor site damage in the majority of the patients.

The pathology of the esophagus is diverse, therefore, disorders of the structural and functional state of the esophagus require different approaches both in the diagnosis of its pathology and in treatment. The review presents data on innovative diagnostic methods for the pathology of the cardio-esophageal transition in pediatric patients. The methods used were literature search in the databases PubMed, Medlit, RSCI, Scopus, Web of Science, EMBASE. Modern ideas about the neurophysiology of the gastroesophageal transition, the mechanisms of its antireflux function, and the pathogenesis of various pathologies of this anatomical localization, mainly gastroesophageal reflux disease (GERD), are described in both infants and school children. The features of the clinical picture of GERD depending on the age of the patient and the nature of the reflux agent are presented. The phenotypes of reflux disease are determined. The characteristics and modifications of existing original methods for studying the cardio-esophageal transition (both their advantages and disadvantages) are described in detail. The approaches to the possible optimization of management of this group of patients are proposed.

The generalizing statistical characteristics of multiyear two-point measurements of atmospheric aerosol parameters carried out in the Middle Urals are presented. The characteristics of the aerosol optical depth (AOD) and specific features of time variations in aerosol turbidity of the atmosphere in Yekaterinburg and the suburban background region are compared. The differences are determined in the mean values, interannual, annual, and daily variations in AOD and in its fine and coarse components obtained using sun photometer measurements in two regions.

The corrected dependence of the mean depth of the EAS maximum $X_{max}$ on the energy was obtained from the data of the Tunka-133 array for 7 years and the TAIGA-HiSCORE array for 2 years. The parameter $\langle\ln A\rangle$, characterizing the mean mass compositon was derived from these results. The differential energy spectrum of primary cosmic rays in the energy range of $2\cdot 10^{14}$ - $2\cdot 10^{16}$\,eV was reconstructed using the new parameter $Q_{100}$ the Cherenkov light flux at the core distance 100 m.}, Comment: 6 pages, 3 figures, Submitted to SciPost Phys.Proc

The ability to control the direction of scattered light is crucial to provide flexibility and scalability for a wide range of on-chip applications, such as integrated photonics, quantum information processing, and nonlinear optics. Tunable directionality can be achieved by applying external magnetic fields that modify optical selection rules, by using nonlinear effects, or interactions with vibrations. However, these approaches are less suitable to control microwave photon propagation inside integrated superconducting quantum devices. Here, we demonstrate on-demand tunable directional scattering based on two periodically modulated transmon qubits coupled to a transmission line at a fixed distance. By changing the relative phase between the modulation tones, we realize unidirectional forward or backward photon scattering. Such an in-situ switchable mirror represents a versatile tool for intra- and inter-chip microwave photonic processors. In the future, a lattice of qubits can be used to realize topological circuits that exhibit strong nonreciprocity or chirality.

We study theoretically driven quantum dynamics in periodic arrays of two-level qubits coupled to the waveguide. We demonstrate, that strongly subradiant eigenstates of the master equation for the density matrix emerge under strong coherent driving for arrays with the anti-Bragg periods $d=\lambda/4,3\lambda/4$... This happens even though are no such states at low driving powers. Thus, our findings show that in the quantum nonlinear regime the domain of existence of subradiant states expands beyond conventional subwavelength structures. These driven states are directly manifested in long-living quantum correlations between the qubit excitations., Comment: 5 pages, 5 figures

We reveal that strongly enhanced generation of photon pairs with narrow frequency spectra and sharp angular correlations can be realised through spontaneous parametric down-conversion in metasurfaces. This is facilitated by creating meta-gratings through nano-structuring of nonlinear films of sub-wavelength thickness to support the extended bound state in the continuum resonances, associated with ultra-high Q-factors, at the biphoton wavelengths across a wide range of emission angles. Such spectral features of photons can be beneficial for various applications, including quantum imaging. Our modelling demonstrates a pronounced enhancement, compared to unpatterned films, of the total photon-pair generation rate normalized to the pump power reaching 1.75 kHz mW−1, which is robust with respect to the angular bandwidth of the pump, supporting the feasibility of future experimental realisations.