Long-Wave Instability of Advective Flows in Inclined Layer with Solid Heat Conductive Boundaries

We investigate the stability of the steady convective flow in a plane tilted layer with ideal thermal conductivity of solid boundaries in the presence of uniform longitudinal temperature gradient. Analytically found the stability boundary with respect to the long-wave perturbations, find the critical Grashof number for the most dangerous among them of even spiral perturbation.Comment: in Russian, 18 pages, 5 figures, submited to Appl. mechanics and physics, RAS Siberian brunch, Novosibirsk, Russia; Key words: advective flow, oblique layer, a longitudinal temperature gradient, long-wave instabilit

Acute Adhesive Small Bowel Obstruction: a Comparative Analysis of Open and Laparoscopic Surgery

Background. Acute adhesive small bowel obstruction (AASBO) is a common surgical emergency requiring immediate interventions. AASBO is a usual indication for both small bowel resection and adhesiolysis. Postoperative adhesions cause 60% of small bowel obstructions.Materials and methods. An analysis of treatment outcomes is presented for 197 acute adhesive small bowel obstruction patients; 63 patients had urgent laparotomy, and 134 were scheduled for laparoscopy. The examination included physical, laboratory, radiological methods (abdominal radiography, ultrasound, CT scan), laparoscopy and intra-abdominal pressure monitoring.Results and discussion. Of 134 patients scheduled for laparoscopic adhesiolysis, only 46.2% had laparoscopy completed, and 53.8% required conversion to laparotomy. The main rationale for conversion were massive adhesions, intraoperative haemodynamic instability, a need for intestinal decompression, as well as rare complications. Laparoscopic operations were reported with the lower vs. laparotomy rates of surgical complications (6.4  vs. 12.69%), mortality (6  vs. 6.3%), shorter hospital stays (6.5 vs. 12 days) and operation times (75 vs. 118 min, respectively).Conclusion. Laparoscopic surgery in acute adhesive small bowel obstruction was feasible in 31.47% patients and in 46.2% — after a diagnostic laparoscopy; however, a thorough patients selection for laparoscopic adhesiolysis is necessary. The first estimated should be the patient’s haemodynamic stability, the severities of condition, adhesions and comorbid cardiorespiratory pathology. Grade I—II adhesions are an indication for laparoscopic surgery

Synthesis of Carboxymethyl Starch for increasing drilling mud quality in drilling oil and gas wells

This paper describes the impact of carboxymethyl starch preparation conditions on physicochemical properties of polysaccharide reagent, widely used as fluid loss reducing agent in drilling mud. Variation of the main parameters of carboxymethylation is researched in the experiment. The following conditions such as temperature and reaction time, amount of water, as well as ratio of NaOH to monochloracetic acid define the characteristics of carboxymethyl starch. The degree of substitution is defined for polysaccharides, as well as the characteristics of samples have been studied by infrared spectroscopy. Rheological characteristics and fluid loss indicator have been investigated to study the impact of the reagents on drilling mud quality

Başkortostan Cumhuriyeti Toratau Jeoparki bal arısı (apis mellifera) popülasyonunda tergit rengi değişimi

A phenetic analysis of the honey bee population of the Toratau Geopark (Russia) was performed. Over 1,000 worker and drone bee samples were collected from 250 colonies in 59 apiaries on the territory of the Toratau Geopark (Gafuriysky, Ishimbaysky, Meleuzovsky, and Sterlitamaksky districts of the Republic of Bashkortostan). Six phenes in worker bees and four phenes in drone bees were recognized. The phenes E, 1R, 2R, and 3R in workers and Is, I, and O-gray in drones were predominant in the honey bee population of the Toratau Geopark, which were associated with subspecies of the Clineage. These phenes can be used as indicators of introgressive hybridization in the local dark European honey bee population. The phenes allow for quick evaluation of certain honey bee colonies hybridization states.Toratau Jeoparkı'ndaki (Rusya) bal arısı popülasyonunun fenetik analizi yapılmıştır. Toratau Jeoparkı topraklarındaki (Başkurdistan Cumhuriyeti'nin Gafuriysky, Ishimbaysky, Meleuzovsky ve Sterlitamaksky bölgeleri) 59 arılıktaki 250 koloniden 1.000'den fazla işçi ve erkek arı örneği toplanmıştır. İşçi arılarda altı fen ve erkek arılarda dört tergit rengi tespit edilmiştir. İşçilerde E, 1R, 2R ve 3R ve erkek arılarda Is, I ve O-gri fenleri Toratau Jeoparkı'ndaki bal arısı popülasyonunda baskındı ve bunlar C soyunun alt türleriyle ilişkiliydi. Bu tergit rengi, yerel koyu Avrupa bal arısı popülasyonunda içsel melezleşmenin göstergeleri olarak kullanılabilir. Bu tergit renkleri, belirli bal arısı kolonilerinin melezleşme durumlarının hızlı bir şekilde değerlendirilmesine olanak sağlamaktadır.The article was prepared with supporting the grant of the head of the Republic of Bashkortostan Radiy Khabirov, grant title "Study of the Bashkir bee population on the territory of the Toratau Geopark

Острый аппендицит: клинико-лабораторные, лапароскопические, патоморфологические параллели

Introduction. Acute appendicitis takes the first place in incidence among acute surgical disorders of the abdominal cavity organs. While many issues of the diagnosis and treatment strategy of this disease have been studied in detail, the diagnosis of acute appendicitis remains primarily a matter of clinical presentation. National guidelines on acute appendicitis also recommend additional methods for a number of stipulated situations; these methods include the Alvarado score. The key goal of this study is to analyse the results of using the Alvarado score in the diagnosis of acute appendicitis and juxtaposing these results with the laparoscopic and pathomorphological data.Materials and methods. This non-randomised prospective study presents the analysis of examination and treatment of 4,941 patients with acute appendicitis from the two periods — from 2006 to 2010 and from 2011 to 2015 — which is before and after the Alvarado score was introduced into the examination protocol. The likelihood of acute appendicitis according to the Alvarado score is evaluated as follows. A score of one to four is interpreted as appendicitis is unlikely; a score of five or six — acute appendicitis is possible, further dynamic observation is required; a score of seven to ten indicates a most probable acute appendicitis.Results and discussion. The total sensitivity of the scoring system exceeded 90%; however, it did not result in a reduction of the number of diagnostic laparoscopies.Conclusion. The authors see as the upsides of the use of the Alvarado score the improvement of the diagnostic precision and the reduced incidence of catarrhal appendicitis (down to 0.1%) and gangrenous forms of appendicitis (from 14.6% to 8.9%) due to a shorter observation period. The authors explain the failure to achieve the result planned by the healthcare funding costs and the drive to obtain a more precise diagnosis.Введение. Острый аппендицит занимает 1-е место в структуре острых хирургических заболеваний органов брюшной полости. Многие вопросы диагностики и лечебной тактики при данном заболевании хорошо разработаны, но в то же время диагностика при остром аппендиците преимущественно и первично остается клинической. В принятых национальных клинических рекомендациях по острому аппендициту дополнительные методы также рекомендованы в перечисленных ситуациях, в них включена оценка по шкале Alvarado. Основной целью настоящего исследования является анализ результатов применения шкалы Alvarado в диагностике острого аппендицита и сопоставление их с данными лапароскопического и патоморфологического исследований.Материалы и методы. Дизайн исследования — нерандомизированное проспективное исследование. Проанализированы результаты обследования и лечения 4941 больного с острым аппендицитом за два периода — с 2006 по 2010 и 2011–2015 гг.: до и после введения в протоколе обследования балльной системы оценки по шкале Alvarado. Вероятность наличия острого аппендицита по шкале Alvarado оценивается следующим образом: при сумме баллов 1–4 — аппендицит маловероятен; при 5–6 — возможен, необходимо динамическое наблюдение; при 7–10 баллах — наиболее вероятен.Результаты и обсуждение. Общая чувствительность балльной оценки составила >90 %, хотя она не привела к сокращению числа диагностической лапароскопии.Заключение. Положительными сторонами шкалы Alvarado авторы считают повышение уточненной диагностики, снижение доли катарального аппендицита (до 0,1 %), гангренозных форм (с 14,6 до 8,9 %) за счет сокращения периода наблюдения. Недостижение запланированного результата объясняют издержками финансирования медицинских услуг, стремлением к уточненной диагностике

Острая спаечная кишечная непроходимость: сравнительный анализ открытых и лапароскопических операций

Background. Acute adhesive small bowel obstruction (AASBO) is a common surgical emergency requiring immediate interventions. AASBO is a usual indication for both small bowel resection and adhesiolysis. Postoperative adhesions cause 60% of small bowel obstructions.Materials and methods. An analysis of treatment outcomes is presented for 197 acute adhesive small bowel obstruction patients; 63 patients had urgent laparotomy, and 134 were scheduled for laparoscopy. The examination included physical, laboratory, radiological methods (abdominal radiography, ultrasound, CT scan), laparoscopy and intra-abdominal pressure monitoring.Results and discussion. Of 134 patients scheduled for laparoscopic adhesiolysis, only 46.2% had laparoscopy completed, and 53.8% required conversion to laparotomy. The main rationale for conversion were massive adhesions, intraoperative haemodynamic instability, a need for intestinal decompression, as well as rare complications. Laparoscopic operations were reported with the lower vs. laparotomy rates of surgical complications (6.4  vs. 12.69%), mortality (6  vs. 6.3%), shorter hospital stays (6.5 vs. 12 days) and operation times (75 vs. 118 min, respectively).Conclusion. Laparoscopic surgery in acute adhesive small bowel obstruction was feasible in 31.47% patients and in 46.2% — after a diagnostic laparoscopy; however, a thorough patients selection for laparoscopic adhesiolysis is necessary. The first estimated should be the patient’s haemodynamic stability, the severities of condition, adhesions and comorbid cardiorespiratory pathology. Grade I—II adhesions are an indication for laparoscopic surgery. Введение. Острая спаечная кишечная непроходимость (ОСКН) является одной из частых причин в экстренной хирургии, требующих выполнения неотложных оперативных вмешательств. ОСКН — наиболее частое показание как для резекции тонкой кишки, так и для адгезиолизиса. В 60 % причиной обструкции тонкой кишки являются послеоперационные спайки.Материалы и методы. Представлен анализ результатов лечения 197 больных с острой спаечной кишечной непроходимостью, из которых 63 пациентам была выполнена экстренная лапаротомия, 134 — планировали лапароскопические операции. В обследовании применяли физикальные, лабораторные, лучевые методы исследования (обзорная рентгенография живота, УЗИ, КТ), лапароскопию, мониторинг внутрибрюшного давления.Результаты и  обсуждение. Из 134  пациентов, запланированных на лапароскопический адгезиолизис, только у 46,2 % операция завершена лапароскопически, в 53,8 % потребовалась конверсия на лапаротомию. Основными причинами конверсии были массивный спаечный процесс, интраоперационная нестабильность гемодинамики, потребность в декомпрессии кишечника, редко — осложнения. При лапароскопических операциях отметили снижение частоты хирургических осложнений по сравнению с лапаротомией (6,4 и 12,69 %), летальности (6 и 6,3 %), сроков госпитализации (6,5 и 12 дней), сокращение продолжительности операций (75 и 118 минут соответственно).Заключение. Хирургическое лечение лапароскопическим методом больных с острой спаечной кишечной непроходимостью возможно у 31,47 % к их общему числу, в 46,2 % — после диагностической лапароскопии, но требуется тщательный отбор больных на лапароскопический адгезиолизис. Прежде всего необходимо оценить тяжесть состояния больных, стабильность гемодинамики, выраженность спаечного процесса и коморбидной кардиореспираторной патологии. Показанием к лапароскопическим операциям является спаечный процесс I– II степени.

Runoff variations in Lake Balkhash Basin, Central Asia, 1779-2015, inferred from tree rings

Long highly-resolved proxies for runoff are in high demand for hydrological forecasts and water management in arid Central Asia. An accurate (R2 = 0.53) reconstruction of October-September discharge of the Ili River in Kazakhstan, 1779–2015, is developed from moisture-sensitive tree rings of spruce sampled in the Tian Shan Mountains. The fivefold extension of the gauged discharge record represents the variability of runoff in the Lake Balkhash Basin for the last 235 years. The reconstruction shows a 40 year long interval of low discharge preceded a recent high peak in the first decade of the 2000s followed by a decline to more recent levels of discharge not seen since the start of the gauged record. Most reconstructed flow extremes (± 2σ) occur outside the instrumental record (1936–2015) and predate the start of large dam construction (1969). Decadal variability of the Ili discharge corresponds well with hydrological records of other Eurasian internal drainages modeled with tree rings. Spectral analysis identifies variance peaks (highest near 42 year) consistent with main hemispheric oscillations of the Eurasian climatic system. Seasonal comparison of the Ili discharge with sea-level-pressure and geopotential height data suggests periods of high flow likely result from the increased contribution of snow to runoff associated with the interaction of Arctic air circulation with the Siberian High-Pressure System and North Atlantic Oscillation

Acute Appendicitis: Clinical Laboratory, Laparoscopic, Pathomorphological Parallels

Introduction. Acute appendicitis takes the first place in incidence among acute surgical disorders of the abdominal cavity organs. While many issues of the diagnosis and treatment strategy of this disease have been studied in detail, the diagnosis of acute appendicitis remains primarily a matter of clinical presentation. National guidelines on acute appendicitis also recommend additional methods for a number of stipulated situations; these methods include the Alvarado score. The key goal of this study is to analyse the results of using the Alvarado score in the diagnosis of acute appendicitis and juxtaposing these results with the laparoscopic and pathomorphological data.Materials and methods. This non-randomised prospective study presents the analysis of examination and treatment of 4,941 patients with acute appendicitis from the two periods — from 2006 to 2010 and from 2011 to 2015 — which is before and after the Alvarado score was introduced into the examination protocol. The likelihood of acute appendicitis according to the Alvarado score is evaluated as follows. A score of one to four is interpreted as appendicitis is unlikely; a score of five or six — acute appendicitis is possible, further dynamic observation is required; a score of seven to ten indicates a most probable acute appendicitis.Results and discussion. The total sensitivity of the scoring system exceeded 90%; however, it did not result in a reduction of the number of diagnostic laparoscopies.Conclusion. The authors see as the upsides of the use of the Alvarado score the improvement of the diagnostic precision and the reduced incidence of catarrhal appendicitis (down to 0.1%) and gangrenous forms of appendicitis (from 14.6% to 8.9%) due to a shorter observation period. The authors explain the failure to achieve the result planned by the healthcare funding costs and the drive to obtain a more precise diagnosis

ETIO-PATHOGENETIC ASPECTS AND TREATMENT POLICY OF INTRA-ABDOMINAL HYPERTENSION

The examination results  of 296 patients suffering from  severe  abdominal pathology in combination with intra-abdominal hypertension are analyzed  in the article. Physical parameters of the  abdominal space  of 30 patients during  video-laparoscopic operations are studied. 3 volume  characteristics of the  abdominal space  are given by the  article writers: reserve volume, maximal volume and physiologic volume, all of them being individual marks depending on sex, age  and  body  type.  The package of measures directed on the  3 main abdominal space components is proposed

CHOICE OF SURGICAL METHOD OF TREATMENT OF CHOLELITHIASIS

This article presents results of surgical treatment of 2963 patients with cholelithiasis. The majority of them (71,8%) had an elective surgery, though 28,2% of patients underwent an emergency operation. A comparative assessment of obligate treatment criteria was made in 2 groups. A first group consisted of 803 patients and it was before introduction of Roman selection criteria used for surgical treatment of patients. A second group included 2963 patients in the period after introduction of selection criteria. Preoperative planning of surgery with evaluation of technical complexity of all stages of intervention with prognosis for possible complications should be the base of reasonable choice of surgical method of treatment of cholelithiasis and safety protection of surgery. The study completed and results obtained allowed decrease of the rate of postoperative complications to 1,4% and lethality - to 0,3%, respectively