Two-tone spectroscopy of a SQUID metamaterial in the nonlinear regime

Compact microwave resonantors made of superconducting rings containing Josephson junctions (SQUIDs) are attractive candidates for building frequency tunable metamaterials with low losses and pronounced nonlinear properties. We explore the nonlinearity of a SQUID metamaterial by performing a two-tone resonant spectroscopy. The small-amplitude response of the metamaterial under strong driving by a microwave pump tone is investigated experimentally and theoretically. The transmission coefficient $S_{21}$ of a weak probe signal is measured in the presence of the pump tone. Increasing the power of the pump, we observe pronounced oscillations of the SQUID's resonance frequency $f_{\textrm{res}}$. The shape of these oscillations varies significantly with the frequency of the pump tone $f_{\textrm{dr}}$. The response to the probe signal displays instabilities and sidebands. A state with strong second harmonic generation is observed. We provide a theoretical analysis of these observations, which is in good agreement with the experimental results

Оценка медицинских технологий в акушерстве: преимущества индивидуального консервативного ведения монохориальной беременности, осложненной синдромом обратной артериальной перфузии, перед хирургическим вмешательством

Introduction. Twin reversed arterial perfusion (TRAP) syndrome is one of the types of complications of monochorial twins (MT) with a frequency of occurrence of 1:35000 births. It is characterized by the presence of the main vessel instead of a normal 4 chambers heart and intrauterine developmental abnormalities. This pregnancy requires monitoring using dynamic ultrasound diagnostics every 7 days, in accordance with current recommendations. The treatment is intrauterine laser coagulation of blood vessels of the “acardial fetus” (AP) in order to prevent the development of a threatening condition for the “fetal pump” (PP). Aim: to demonstrate the possibilities of comprehensive conservative management of monochorial pregnancy complicated by TRAP.Materials and methods. An ultrasound examinations were performed on a weekly basis in monochorionic pregnancy, complicated by TRAP within the period 12-38 weeks. Serum concentrations of biochemical markers PAPP-A (pregnancy-associated plasma protein-A) and β-hGC (β-subunit of human chorionic gonadotropin) were studied in the first trimester to predict adverse perinatal outcomes.Results. The possibility of prolonging a pregnancy complicated by TRAP without performing intrauterine surgical intervention, during which quite serious complications can occur in this category of pregnancies, has been demonstrated. In a patient with monochorionic twins complicated by TRAP, totally 27 ultrasound examinations were performed within the period 12-38 weeks. This approach made it possible to dynamically monitor the condition of a pregnant and healthy fetus and to prolong pregnancy without surgery until the full term.Conclusions. Following the existing guidelines, without tailoring for individual risk, may lead to an unreasonable increase in surgical interventions. In turn, surgery is not only accompanied by a high risk of complications (up to 15%), but also constitute a certain financial burden on the budget, determined by the state on the level of 208,000 rubles. Performing routine ultrasound examinations according to the examination protocol for monochorionic pregnancy will contribute to avoiding the complications associated with surgery and better selection for surgery as well as reducing the government costs. Введение. Синдром обратной артериальной перфузии (СОАП) – один из видов осложнений монохориальной двойни (МХ) с частотой встречаемости 1:35000 родов, характеризующийся наличием магистрального сосуда вместо полноценного сердца у одного близнеца (акардиальный плод) и нарушениями внутриутробного развития разной степени. Данная беременность требует наблюдения с динамикой ультразвукового исследования (УЗИ) каждые 7 дней, что определено практическими рекомендациями. Операцией выбора является внутриутробная лазерная коагуляция сосудов, питающих акардиальный плод (АП) с целью не допустить развития угрожающих состояний для плода-помпы (ПП).Цель – продемонстрировать возможности успешного консервативного ведения монохориальной беременности, осложненной СОАП.Материалы и методы. УЗИ при монохориальной беременности двойней проводилось еженедельно, в течение 12-38 недель беременности. В первом триместре выполнялось исследование сывороточных концентраций биохимических маркеров PAPP-A (англ. – pregnancy-associated plasma protein-A, ассоциированный с беременностью протеин-А плазмы) и β-ХГЧ (свободная бета-субъединица хорионического гонадотропина человека) с целью прогнозирования неблагоприятных перинатальных исходов.Результаты. Продемонстрирована возможность пролонгации беременности, осложненной СОАП, без выполнения внутриутробного хирургического вмешательства (ВХ), в ходе которого в данной категории беременностей могут иметь место достаточно серьезные осложнения. У пациентки с монохориальной двойней, осложненной развитием СОАП, было выполнено 27 УЗИ в период 12-38 недель. Такой подход позволил динамически наблюдать за состоянием беременной и здорового плода и пролонгировать беременность без проведения хирургической операции до доношенного срока.Заключение. Следование регламентированным практическим рекомендациям к проведению ВХ, без учета индивидуальных особенностей каждого отдельного случая, может потенциально приводить к необоснованному увеличению оперативных вмешательств, повышая прямые затраты. ВХ не только сопровождаются высоким риском осложнений (до 15%), но и накладывают высокую финансовую нагрузку на бюджет, определенный государством на сегодняшний день квотой 208000 рублей. Выполнение рутинного УЗИ, согласно протоколу обследования для МХ, может способствовать снижению риска осложнений, ассоциированных с ВХ, более качественному отбору потенциальных кандидатов для ВХ, а также связанному с этим снижению бюджетных затрат на оказание медицинской помощи

Fuzzy logic foundations of optimal inference

In this paper we propose to solve the problem of the optimal fuzzy model designing for the dynamic systems controlling, to develop new mathematical models of fuzzy inference, logical schemes of hardware support based on these models, software support, intellectual system based on these models. The proposed schemes will be able to perform an entire inference process required for real--time fuzzy control. Each scheme works independently of the number of control rules in the knowledge base. The necessary accuracy of the output results can be provided. Among the advantages of suggested architectures are: gain in memory size, simplicity in architectural decisions, fast implementation. The proposed intellectual system gives the new approaches to fuzzy logics acquisitionin the ES and FLC, based on t-norms approach. The system is supplied by cognitive graphics interface. The main functions of the system are: visualization of fuzzy logics by multi-color tables, fuzzy logics acquisition, simulation the fuzzy reasoning processes of the system, testing of fuzzy logics

Antenatal fetal death in multiple pregnancy: is early prediction possible?

Introduction. Perinatal mortality in multiple pregnancies increases by 8–10 times compared to singletons. Stillbirth is a significant part of all complications of multiple pregnancies. Although the incidence of perinatal mortality in multiple pregnancies has decreased consistently compared to extremely high rates in the past, it remains relatively high, despite significant positive changes in the management of such pregnancies. Aim: to assess the diagnostic potential of the first trimester's biochemical screening in multiple pregnancies for predicting antenatal fetal death. Materials and Methods. As part of a retrospective study, a cohort of twin pregnancies after in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), or spontaneous conception underwent screening of the first trimester at 11+0–13+6 weeks of gestation as recommended by the Fetal Medicine Foundation. Determination of pregnancy-associated plasma protein-A (PAPP-A) in blood serum with subsequent calculation of the relative PAPP-A MoM (multiples of median) – a multiple of the median (an indicator of how much the individual test result deviates from the reference values) was performed. Results. Prenatal screening and outcomes of 302 multiple pregnancies showed that with PAPP-A MoM < 0.5, antenatal fetal death occurred with a frequency of 42.86 % (6/14), with PAPP-A MoM within the reference values – In 12.67 % (28/221), with PAPP-A MoM > 2.0 – in 6.7 % (2/30). Differences between patients with PAPP-A MoM < 0.5 and PAPP-A MoM within the reference values, as well as PAPP-A MoM < 0.5 and PAPP-A MoM > 2.0 were statistically significant (p = 0.002 and p = 0.004, respectively). No differences were detected between spontaneous and assisted reproductive technology (ART) pregnancies. Conclusion. In women with multiple pregnancies resulting from ART or spontaneous, PAPP-A MoM values below the reference interval (< 0.5) in the first trimester are associated with an increased risk of antenatal fetal death

Anal Incontinence after Anterior Rectum Resection in Cancer Patients

Aim. To study the functioning of the anal sphincter after performing anterior rectum resection in cancer patients.Materials and methods. The anal sphincter function was studied in 144 patients with colorectal cancer, equally in 72 men and 72 women. The study was carried out at the Rostov Cancer Research Institute. All patients underwent R0 anterior rectum resection with the total mesorectumectomy and the formation of a preventive ileostomy. An assessment of the retention function was performed by sphincterometry using a manometric complex with a nonperfusion water-filling sensor according to the generally accepted method.Results. Disturbances in the normal functioning of the sphincter were noted in 24 (16.7 %) patients. The use of sphincterometry allowed disturbances in the functioning of the internal and external anal sphincters in men and women to be identified, along with differences between the groups. The results indicate a higher incidence of anal incontinence (AI) in women compared to men (t ≥ 2, the differences are significant). In addition, patients with a lower localisation of the anastomosis demonstrated a higher incidence of AI and more pronounced AI manifestations.Conclusions. The obtained data on the functioning of the anal sphincter after anterior rectum resection in cancer patients indicate gender differences in the incidence of late complications after surgery, as well as the importance of taking into account the localisation of the tumour for selecting an adequate amount of surgical intervention