Score twice before you cut once: a clinical case of reconstructive bariatric surgery after obesity surgery in a patient with postoperative hypothyroidism and hypoparathyroidism

Hundreds of thousands of bariatric surgeries are performed worldwide every year. Th ey have long been proven to be safe and eff ective in treating obesity and type 2 diabetes. Along with an unconditional positive eff ect, these interventions, especially shunting ones, are characterized by specifi c complications. In the absence of proper correction, they can become fatal for patients. One of these complications is malabsorption leading to a defi ciency of vitamins and microelements, which in most cases, is amenable to timely correction in the postoperative period. However, there are situations when it is not possible to carry out an eff ective correction and it becomes necessary to perform reconstructive interventions with the reverse inclusion of the small intestine in the digestion, which is associated with great diffi culties. Th e authors demonstrated this situation in the description of clinical observation of a patient with postoperative hypothyroidism and history of postoperative hypoparathyroidism, who underwent bariatric surgery. Impaired absorption of drugs (L-thyroxine, calcium, and vitamin D), and therefore, uncompensated hypothyroidism and hypocalcemia was an indication for reconstructive surgery

Flat surfaces machining by the magneto-abrasive method with permanent magnet end-type heads 2. The influence of the design of the working surfaces of the heads on the effectiveness of the magneto-abrasive machining

Виконано дослідження процесу магнітно-абразивного оброблення плоских поверхонь деталей з феромагнітного матеріалу сталь 45 торцевими головками на базі високопотужних постійних магнітів, які формують магнітно-абразивний інструмент типу «щітка». Для забезпечення високої ефективності процесу магнітно-абразивного оброблення виконано аналіз оброблення головками на робочих поверхнях яких виконані виступи різної форми, розмірів і конфігурації. Досліджено дванадцять типів робочих поверхонь. Контроль ефективності процесу магнітно-абразивного оброблення виконували за зміною параметра Ra, величини відносної шорсткості і швидкості її зміни, величини опорної поверхні формуючогося мікро-профілю та параметра геометричної спадковості, отриманої при обробленні. Встановлено, що найбільш раціональною конструкцією робочої поверхні торцевої головки з магнітно-абразивним інструментом типу «щітка» буде поверхня, з нанесеними на неї 9 - 12 променеподібними виступами трикутної форми. Використання таких головок забезпечує високоефективне формування шорсткості оброблених поверхонь з Ra <0,03 мкм при початковій Ra на рівні 0,8 мкм, отриманій після торцевого фрезерування. При цьому практично повністю усувається мікрохвилястість, що формується при фрезеруванні. За характером зміни величини відносної опорної поверхні мікропрофілю проаналізована кінетика його формування. Показано, що на початковому етапі відбувається переважне видалення мікровиступів, в подальшому активно обробляються мікровпадини з подальшим вигладжуванням мікропрофілю.Investigation of the magneto-abrasive machining process of flat surfaces of parts made of ferromagnetic material steel 45 by the end heads based on high-power permanent magnets, which form the magneto-abrasive tool of the "brush" type, was carried out. For ensuring the high efficiency of the magneto-abrasive machining process, an analysis of the machining by heads on the working surfaces of which located protrusions of various shapes, sizes and configurations was carried out. Twelve types of working surfaces were investigated. The control of magneto-abrasive machining process efficiency was curried for the changing of the parameter Ra, the value of the relative roughness and the rate of its change, the size of the surface's relative reference profile length from the section level of the formed microprofile and the parameter of geometric heredity obtained during the machining. It has been determined that the most rational design of the working surface of the end head with the magneto-abrasive tool of the “brush” type was the surface with 9–12 radial triangular protrusions located on it. Using of such heads provides a highly efficient form of the roughness of machined surfaces with Ra < 0.03 m with an initial Ra of 0.8 m obtained after face milling. At the same time, microwaves had been formed after milling was almost eliminated. The kinetics formation of the relative reference profile length from the section level was analyzed by the nature of its size change. It was shown that at the initial stage, the predominant removal of micro peaks had occurred, and then micro valleys were actively machined with further smoothing of the microprofile.Выполнены исследования процесса магнитно-абразивной обработки плоских поверхностей деталей из ферро-магнитного материала сталь 45 торцевыми головками на базе высокомощных постоянных магнитов, формирующих магнитно-абразивный инструмент типа «щетка». Для обеспечения высокой эффективности процесса магнитно-абразивной обработки выполнено анализ обработки головками на рабочих поверхностях которых выполнены выступы разной формы, размеров и конфигурации. Исследовано двенадцать типов рабочих поверхностей. Контроль эффективности процесса магнитно-абразивной обработки выполняли по изменению параметра Ra, величины относительной шероховатости и скорости ее изменения, величины опорной поверхности формируемого микропрофиля и параметра геометрической наследственности, полученной прио бработке. Установлено, что наиболее рациональной конструкцией рабочей поверхности торцевой головки с магнитно-абразивным инструментом типа «щетка» будет поверхность, с нанесенными на нее 9 - 12 лучеобразными вы-ступами треугольной формы. Использованиетакихголовокобеспечиваетвысокоэффективноеформированиешероховато-стиобработанныхповерхностейс Ra < 0,03 мкм при исходной Ra науровне 0,8 мкм, полученной после торцевого фрезеро-вания. При этом практически полностью устраняется микроволнистость, формирующаяся при фрезеровании. По характеру изменения величины относительной опорной поверхности микропрофиля проанализирована кинетика его формирования. Показано, что на начальном этапе происходит преимущественное удаление микровыступов, в последующем активно обрабатываются микровпадины с дальнейшим выглаживанием микропрофиля

A METHOD OF FORMING A GROUP TIME SCALE BASED ON COMBINING SEPARATE STATISTICALLY EQUIVALENT FREQUENCY STANDARDS

The article describes one of the approaches to the formation of a group timeline information management systems by combining in ensembles of similar frequency standards

Methodology for Solving High-dimensional Multi-Parameter Inverse Problems of Indirect Measurements

Inverse problems (IP) of indirect measurements are a class of IP encountered in most modern nature science experiments. Unfortunately, they are characterized by a number of properties making them hard to solve: they may be ill-posed or even incorrect, non-linear, and often they are characterized by high dimension by input and/or by output. As such, IP of indirect measurements require special methods to solve them. One of the classes of such methods are methods of machine learning (ML), which however possess special properties which should be taken into account when using them. In this paper, the authors suggest an outline of a special methodology, which can become the base for a standard scenario for processing data of indirect measurement IP with ML methods. The main notions underlying this methodology are also described and explained

Design of an Universal Source for Semi-automatic Ac Welding and Induction Heating

This paper proposes a circuit solution and a power source control algorithm for semi-automatic AC welding with improved energy and weight-size characteristics. A distinctive feature of the designed source is the absence of an input rectifier: welding is carried out with a high-frequency alternating current. That has made it possible to significantly reduce power losses in the source, as well as provide the possibility of implementing induction heating by connecting an inductor to the source output. Another distinctive feature of the designed source is an increased power factor and a reduced level of higher harmonics of the current consumed. The power factor of the described source reaches 0.94 against 0.5÷0.7 for sources equipped with a conventional rectifier with capacitive smoothing. The designed source's composition includes a power supply system for the wire feed drive with speed stabilization due to positive feedback on the motor current. That has made it possible to ensure the stable operation of the drive in a wide range of speeds. A model has also been developed of a flux wire welding torch containing a feed drive and a coil with a wire (up to 100 mm in diameter), placed, in order to reduce the size, in the handle of the torch. In addition to the welding function, the source makes it possible to solve the tasks related to induction heating and/or hardening of small parts; to that end, a compact inductor is connected to its output. Tests of the source showed the feasibility of the proposed ideas and circuit solutions. The dimensions of the source are 190×107×65 mm; weight, 1.4 kg; output current, up to 120 A. The proposed technical solution enables the construction of small-sized, lightweight, universal, easy-to-use power supplies for semi-automatic welding with the option of induction heatin