Specific heat and magnetocaloric effect in Pr1-xAgxMnO3 manganites

The magnetocaloric effect in alternating magnetic fields has been investigated in Pr1-xAgxMnO3 manganites with x=0.05-0.25. The stepwise reversal of the sign of the magnetocaloric effect has been revealed in a weakly doped sample (x=0.05) at low temperatures (~80 K). This reversal is attributed to the coexistence of the ferromagnetic and canted antiferromagnetic phases with different critical temperatures.Comment: 4 pages, 4 figure

Argon plasma coagulation in coloproctology: clinical experience with and prospects for the technique

Background. Rectal laterally spreading tumors (LSTs) are macroscopically divided into granular (LST-G) and non-granular (LST-NG). LST-Gs have in turn two types: homogeneous and nodular mixed.Subjects and methods. The retrospective study analyzed the data of 20 patients (11 men and 9 women) in whom homogenous LSTs were removed by argon plasma coagulation (APC). The patients» mean age was 65.8 ± 6 years. Therapeutic effectiveness was evaluated by Ki-67 proliferation index and the frequency of complications and recurrences.Results. The average size of removed homogeneous LST-Gs was 12.3 ± 3.8 cm2. The average number of APC sessions to achieve a LST-G reduction was 4.4 ± 0.9. Three days before APC, Ki-67 in the neoplasia biopsy specimens amounted to as much as 67.8 ± 4.4 % on average; it reduced to an average of 33.0 ± 3.0 % at 14 days of APC initiation, 16.5 ± 1.8 and 4.2 ± 0.4 % after 21 and 180 days, respectively.Discussion. Inability to receive complete histological data on removed LST-Gs is a main pitfall in APC.Conclusion. Stepwise tumor APC may be the method of choice in elderly and senile patients with a family history of comorbidity. APC can precisely remove LSTs along the boundary of the dentate line. This technique requires no single-use tools

Social function of taxes as a toolkit for income differentiation reduction among population of the depressed republics of the North Caucasus Federal District

In the conditions of a difficult political situation, economic uncertainty and increasing unemployment in the land-poor manpower-surplus, depressive republics of the North Caucasus Federal District, the need to implement the entrepreneurial opportunities of the population is clearly manifested. It seems that small business can manifest itself in these conditions as a separate element of the economy decentralized sector. Of course, the success of small business in a depressed region depends on the state position to a large extent. And this is natural, because only the state is capable of creating the necessary conditions in market relations and various preference provision for the development of entrepreneurship, especially in the mountainous territories of the country.It should be noted that the next economic crisis and pandemic (coronavirus) not only led to the depletion of the state budget, but also collapsed the production activity of small diversified enterprises in the region. Most of the entrepreneurs of the North Caucasus Federal District declare that they are not able to independently solve the complex of this phenomenon negative consequences

Critical sound attenuation in a diluted Ising system

The field-theoretic description of dynamical critical effects of the influence of disorder on acoustic anomalies near the temperature of the second-order phase transition is considered for three-dimensional Ising-like systems. Calculations of the sound attenuation in pure and dilute Ising-like systems near the critical point are presented. The dynamical scaling function for the critical attenuation coefficient is calculated. The influence of quenched disorder on the asymptotic behaviour of the critical ultrasonic anomalies is discussed.Comment: 12 RevTeX pages, 4 figure

Аргоноплазменная коагуляция в колопроктологии: клинический опыт и перспективы метода

Background. Rectal laterally spreading tumors (LSTs) are macroscopically divided into granular (LST-G) and non-granular (LST-NG). LST-Gs have in turn two types: homogeneous and nodular mixed.Subjects and methods. The retrospective study analyzed the data of 20 patients (11 men and 9 women) in whom homogenous LSTs were removed by argon plasma coagulation (APC). The patients» mean age was 65.8 ± 6 years. Therapeutic effectiveness was evaluated by Ki-67 proliferation index and the frequency of complications and recurrences.Results. The average size of removed homogeneous LST-Gs was 12.3 ± 3.8 cm2. The average number of APC sessions to achieve a LST-G reduction was 4.4 ± 0.9. Three days before APC, Ki-67 in the neoplasia biopsy specimens amounted to as much as 67.8 ± 4.4 % on average; it reduced to an average of 33.0 ± 3.0 % at 14 days of APC initiation, 16.5 ± 1.8 and 4.2 ± 0.4 % after 21 and 180 days, respectively.Discussion. Inability to receive complete histological data on removed LST-Gs is a main pitfall in APC.Conclusion. Stepwise tumor APC may be the method of choice in elderly and senile patients with a family history of comorbidity. APC can precisely remove LSTs along the boundary of the dentate line. This technique requires no single-use tools.Введение. Горизонтально распространяющиеся стелющиеся образования (laterally spreading tumor, LST) прямой кишки макроскопически подразделяются на гранулированные (LST granular, LST-G) и негранулированные (LST non-granular, LST-NG). LST-G, в свою очередь, бывают 2 типов: однородные (homogeneous type) и однородные с узлами (nodular mixed type).Материалы и методы. Выполнено ретроспективное исследование данных 20 пациентов (11 мужчин и 9 женщин), которым за период с 2006 по 2011 г. удалили методом аргоноплазменной коагуляции (АПК, argon plasma coagulation) LST-G однородного типа. Средний возраст больных составил 65,8 ± 6 лет. Эффективность лечения оценивали по индексу пролиферации Ki-67, частоте осложнений и рецидивов.Результаты. Средний размер удаленных LST-G однородного типа был 12,3 ± 3,8 см2. Среднее количество этапов АПК для достижения редукции неоплазии типа LST-G составило 4,4 ± 0,9. Индекс пролиферации Ki-67 в биоптатах неоплазий за 3 сут до АПК достигал в среднем 67,8 ± 4,4 %, на 14-е сутки после начала АПК снижался в среднем до 33,0 ± 3,0 %, через 21 сут – до 16,5 ± 1,8 %, через 180 сут – до 4,2 ± 0,4 %.Обсуждение. Основным недостатком АПК является невозможность получения полной гистологической информации удаленных LST-G.Заключение. Этапная АПК образований может быть методом выбора у пациентов пожилого и старческого возраста с наличием отягощающей сопутствующей патологии. АПК позволяет прецизионно удалять LST, распространяющиеся по границе зубчатой линии. Применение метода не требует приобретения одноразовых инструментов

Compression method of anastomosis of large intestines by implants with memory of shape: alternative to traditional sutures

Research objective. To prove experimentally the possibility of forming a compression colonic anastomoses using nickel-titanium devices in comparison with traditional methods of anastomosis. Materials and methods. In experimental studies the quality of the compression anastomosis of the colon in comparison with sutured and stapled anastomoses was performed. There were three experimental groups in mongrel dogs formed: in the 1st series (n = 30) compression anastomoses nickel-titanium implants were formed; in the 2nd (n = 25) – circular stapling anastomoses; in the 3rd (n = 25) – ligature way to Mateshuk– Lambert. In the experiment the physical durability, elasticity, and biological tightness, morphogenesis colonic anastomoses were studied. Results. Optimal sizes of compression devices are 32 × 18 and 28 × 15 mm with a wire diameter of 2.2 mm, the force of winding compression was 740 ± 180 g/mm2. Compression suture has a higher physical durability compared to stapled (W = –33.0; p < 0.05) and sutured (W = –28.0; p < 0.05), higher elasticity (p < 0.05) in all terms of tests and biological tightness since 3 days (p < 0.001) after surgery. The regularities of morphogenesis colonic anastomoses allocated by 4 periods of the regeneration of intestinal suture. Conclusion. Obtained experimental data of the use of compression anastomosis of the colon by the nickel-titanium devices are the convincing arguments for their clinical application

Morphotropic Phase Boundary Enhanced Photocatalysis in Sm Doped BiFeO3

This paper presents the results of the synthesis of samarium-doped bismuth ferrite (BFO) nanoparticles by the solution combustion method. The dependence of BFO properties on the amount of the samarium (Sm) in the composition was studied. The synthesized nanocomposites were characterized by scanning electron microscopy SEM), X-ray diffractometry (XRD), Raman, Electron Diffuse Reflectance Spectroscopy (EDRS) and Electron Magnetic Resonance (EMR). The photocatalytic (PC) measurements showed the absence of a strict correlation between the PC activity and the crystallite size and band gap. An increase in the PC activity of BFO samples with 10 and 15% doping was observed and it was concluded that in controlling the PC properties in doped BFO, the processes of interfacial polarization at the boundaries of the morphotropic phase transition are of decisive importance. It was supposed that the internal electric field formed at these boundaries contributes to the efficient separation of photogenerated charge carriers

Роль консервативной терапии в лечении осложненного колоректального рака

Objective: to evaluate the possibilities of conservative treatment of patients with complications of colorectal cancer.Materials and methods. The study included the results of treatment of 105 patients with complications of colorectal cancer treated on the basis of the District Clinical Hospital of Surgut for the period 2012—2017. Of these, 86 (81.9 %) patients with acute obstructive intestinal obstruction, 11 (10.5 %) patients with bleeding from colon tumors, and 8 (7.6 %) patients with purulent-septic complications of colon cancer.Results. The complex of conservative measures, including colon stenting, provides restoration of the passage through the digestive tract in 79.1 % of patients, which allows preparing the patient to perform surgery, thereby reducing the risk of complications. Twenty-eight (27.6 %) patients were operated on an emergency basis: due to the lack of effect from conservative therapy for acute intestinal obstruction — 18 (17.1 %) patients, due to peritonitis — 8 (7.6 %), due to recurrent colonic bleeding — 3 (2.9 %) patients. The death rate was 13.8 % (n = 4). In the delayed order after successful conservative therapy, 70 (66.7 %) patients underwent surgical treatment in the surgical and oncology departments. Postoperative mortality was 1.4 % (n = 1).Conclusion. The complex of conservative measures, which allows avoiding emergency surgical intervention at the urgent stage of treatment, is the basis for carrying out a full-fledged surgical intervention in a delayed procedure in a specialized hospital, observing the principles of oncological radicalism.Цель исследования — оценка возможности консервативного лечения больных с осложнениями колоректального рака. Материалы и методы. Исследование обобщает результаты лечения 105 больных с осложнениями колоректального рака, пролеченных на базе Окружной клинической больницы г. Сургута за период 2012—2017 гг. В их числе 86 (81,9 %) пациентов с острой обтурационной кишечной непроходимостью, 11 (10,5 %) — с кровотечением из опухоли толстой кишки, 8 (7,6 %) — с гнойно-септическими осложнениями рака толстой кишки.Результаты. Комплекс консервативных мероприятий, включающих стентирование толстой кишки, обеспечил восстановление пассажа по пищеварительному тракту у 79,1 % пациентов, что позволило подготовить их к выполнению хирургического вмешательства, тем самым уменьшив риск развития осложнений. В экстренном порядке были оперированы 29 (27,6 %) пациентов: в связи с отсутствием эффекта от консервативной терапии при острой кишечной непроходимости — 18 (17,1 %), в связи с перитонитом — 8 (7,6 %), в связи с рецидивом толстокишечного кровотечения — 3 (2,9 %). Частота летальных исходов составила 13,8 % (п = 4). В отсроченном порядке после успешной консервативной терапии 70 (66,7 %) больных подвергнуты хирургическому лечению в условиях хирургического и онкологического отделений. Послеоперационная летальность составила 1,4% (п = 1).Выводы. Комплекс консервативных мероприятий, позволяющий избежать экстренного хирургического вмешательства на ургентном этапе лечения, обеспечивает возможность проведения полноценного хирургического вмешательства в отсроченном порядке в специализированном стационаре с соблюдением принципов онкологического радикализма

Компрессионный способ анастомозирования толстой кишки имплантатами с памятью формы - альтернатива традиционным швам

Research objective. To prove experimentally the possibility of forming a compression colonic anastomoses using nickel-titanium devices in comparison with traditional methods of anastomosis. Materials and methods. In experimental studies the quality of the compression anastomosis of the colon in comparison with sutured and stapled anastomoses was performed. There were three experimental groups in mongrel dogs formed: in the 1st series (n = 30) compression anastomoses nickel-titanium implants were formed; in the 2nd (n = 25) – circular stapling anastomoses; in the 3rd (n = 25) – ligature way to Mateshuk– Lambert. In the experiment the physical durability, elasticity, and biological tightness, morphogenesis colonic anastomoses were studied. Results. Optimal sizes of compression devices are 32 × 18 and 28 × 15 mm with a wire diameter of 2.2 mm, the force of winding compression was 740 ± 180 g/mm2. Compression suture has a higher physical durability compared to stapled (W = –33.0; p < 0.05) and sutured (W = –28.0; p < 0.05), higher elasticity (p < 0.05) in all terms of tests and biological tightness since 3 days (p < 0.001) after surgery. The regularities of morphogenesis colonic anastomoses allocated by 4 periods of the regeneration of intestinal suture. Conclusion. Obtained experimental data of the use of compression anastomosis of the colon by the nickel-titanium devices are the convincing arguments for their clinical application. Цель исследования – путем проведения эксперимента обосновать преимущества компрессионных толстокишечных анастомозов, сформированных с помощью никелид-титановых (TiNi) проволочных устройств, относительно традиционных способов анастомозирования. Материалы и методы. В ходе проведенного экспериментального исследования мы оценили качество компрессионного анастомоза толстой кишки по сравнению с лигатурным и механическим способами формирования соустья. Были созданы 3 экспериментальные группы, включающие беспородных собак: в 1-й группе (n = 30) компрессионные анастомозы формировались TiNi-имплантатами; во 2-й (n = 25) – циркулярными сшивающими аппаратами; в 3-й (n = 25) – лигатурным способом по Матешуку–Ламберу. В процессе исследования были изучены механическая прочность, эластичность и биологическая герметичность толстокишечных анастомозов, морфогенез анастомозов. Результаты. Оптимальными считаем устройства для компрессионного создания анастомозов размерами 32 × 18 и 28 × 15 мм с диаметром провода 2,2 мм, силой межвиткового сдавления тканей 740 ± 180 г/мм2. Компрессионный шов обладает более высокой физической герметичностью по сравнению с механическим (W = –33,0; p < 0,05) и ручным швами (W = –28,0; p < 0,05), а также более высокой эластичностью (р < 0,05) на протяжении всего срока исследования и более высокой биологической герметичностью (р < 0,001) с 3-х суток после операции. Установлены закономерности морфогенеза толстокишечных анастомозов, выделены 4 периода регенерации кишечного шва. Заключение. Результаты экспериментального исследования по изучению компрессионного анастомоза толстой кишки TiNi-проволочными устройствами считаем серьезным основанием для внедрения этого способа анастомозирования в клиническую практику.