Актуальные проблемы гидрологических расчетов в арктической зоне Российской Федерации и сопредельных территориях распространения многолетней мерзлоты

The article reveals the main problems facing hydrologists in engineering design in the Arctic zone of Russia and adjacent territories of permafrost. Climate warming and degradation of permafrost cause a significant transformation of the hydrological cycle. The retrospective observations of runoff cannot be considered therefore in modern conditions. The density of the hydrological network in the permafrost zone of Russia has decreased by more than 1.5 times, and on small rivers – more than three times in recent decades. Thus, the use of standard calculation methods (SP 33-101-2003) to assess the runoff characteristics in the Arctic regions is practically impossible. It is shown that in the developed Arctic countries where the size of the territories and their inaccessibility could be compared with withRussia, the low density of the standard observation network is compensated by the organization of small scientific research stations for studying hydrological processes in various physical and geographical conditions and the development of mathematical modeling methods. It is shown that historicallyRussiawas the leader of hydrological research in cold regions. It is stated that there is an urgent need to create a state program aimed at restoring the previously operating in the cryolithоzone and organizing new research hydrological watersheds, improving the standard hydrological network, and developing complex modeling systems and methods for their parameterization.В статье раскрыты основные проблемы, стоящие перед гидрологами при инженерном проектировании в Арктической зоне России и прилегающих территориях распространения многолетней мерзлоты. Основной из них является практическая невозможность использования стандартных методов расчета (СП 33-101-2003) для оценки характеристик стока в регионах с крайне ограниченными данными наблюдений гидрометрической сети в современных условиях изменений климата. Констатируется срочная необходимость создания государственной программы, направленной на восстановление ранее действовавших в криолитозоне и организацию новых научно-исследовательских гидрологических стационаров, совершенствование стандартной гидрологической сети, а также развитие комплексных моделирующих систем и методов их параметризации

The dynamic model of enterprise revenue management

The article presents the dynamic model of enterprise revenue management. This model is based on the quadratic criterion and linear control law. The model is founded on multiple regression that links revenues with the financial performance of the enterprise. As a result, optimal management is obtained so as to provide the given enterprise revenue, namely, the values of financial indicators that ensure the planned profit of the organization are acquired

Многолетняя динамика гигантской Анмангындинской наледи на Северо-Востоке России (1962–2021 гг.)

The huge Anmangynda aufeis is located in the valley of the river of the same name in the Magadan region in North-East of Russia. This is the only in the world aufeis site with a 30-years period of ground-based observations (1962–1991). The materials of these observations were supplemented with data obtained from the analysis of Landsat and Sentinel satellite images for the period 2000–2021, as well as the results of field investigations carried out in 2020–2021. The long-term variability of the maximum area, volume and average thickness of ice, the dynamics of formation and destruction of the aufeis ice in the cold and warm periods of the year were analyzed. It was found that the maximum values of the area and volume of ice on the dates before the start of ablation decreased by 25 and 33%, respectively. In 2000–2021, the average values of the aufeis characteristics are estimated as 4.7 km2 and 7.1 million m3, while in 1962–1991 – 5.5 km2 and 8.5 million m3. The analysis of the intra-annual dynamics revealed that the Anmangynda aufeis being earlier the perennial formation has transformed to the seasonal one. Further researches of the Anmangynda aufeis will make possible to assess the influence of various factors, including climatic ones, on the processes of an aufeis formation and to forecast their changes in the future for the cryolitic zone of the North-East of our country.Приводятся материалы о многолетней и сезонной изменчивости морфометрических характеристик гигантской наледи в долине реки Анмангында на Северо-Востоке России. Показано, что за последние 60 лет максимальная площадь тарына сократилась на 25%, а объём на 33%. Период абляции ледяного массива уменьшился на 34 дня, наледь из разряда перелетовывающей перешла в категорию сезонных образований

Геофизические признаки источников гигантской наледи на р. Анмангында (Магаданская область)

Giant aufeis fields are the indicators of water exchange processes in the permafrost zone. The study of aufeis dynamics is relevant to assessing the state of the cryosphere in a changing climate. The Anmangynda aufeis which forms upstream of the Kolyma River basin, was as large as 6.8 km2 in the last century and is considered representative of the mountainous territories in the northeast Russia. In recent decades, there have been significant changes in the aufeis formation regime that require updating the understanding of the cryosphere processes. The historical observational data obtained in 1962-1990 for the Anmangynda aufeis allows using it as the present-day object of research.The main goal of geophysical research in 2021-2022 was to study the structure of the Anmangynda aufeis and aufeis glade to determine its genesis and development processes. The main tasks were to identify the boundary between frozen and unfrozen rocks, to reveal groundwater discharge channels, and to assess the aufeis thickness distribution. There were carried out georadar survey using an antenna unit with central frequency of 250 MHz and ground-based capacitively coupled electrical resistivity tomography. It was found that by April 5, 2021, the maximum ice thickness was 4.35 m with an average value of 1.35 m, and the volume of aufeis was 3.56 million m3. By means of georadar, there were performed identification and drilling verification of the groundwater discharge channels from alluvium to aufeis surface, located in the stream beds. There is geophysical evidence of deep bedrock groundwater sources. Based on the electrical resistivity tomography data, there were identified large and locally freezing river taliks, from which the water is squeezed onto the ice surface. It is recommended to conduct further interdisciplinary research to clarify the geophysical results obtained.Гигантские наледи являются индикаторами процессов водообмена в зоне распространения мерзлоты. Исследование динамики наледей является актуальной задачей оценки состояния криосферы в изменяющемся климате. Анмангындинская наледь, формирующаяся в верховьях бассейна р. Колымы, в прошлом веке достигала размеров 6.8 км2 и считается репрезентативной для горных территорий северо-востока России. В последние десятилетия произошли значительные изменения режима наледеобразования, требующие актуализации представлений о процессах криолитозоны. Наличие исторических данных наблюдений на Анмангындинской наледи позволяет использовать ее как объект исследований в настоящее время.Целью геофизических исследований 2021-2022 гг. являлось изучение строения Анмангындинской наледи и наледной поляны для уточнения ее генезиса и процессов формирования. Основными задачами были выявление границ мерзлых и талых пород, каналов разгрузки подземных вод и оценка распределения толщины наледного льда. Проведены георадиолокационные зондирования с антенным блоком центральной частоты 250 МГц и электротомография с заземлениями через емкостную связь. Установлено, что к 5 апреля 2021 г. максимальная толщина льда составила 4.35 м при среднем значении 1.35 м, объем наледи - 3.56 млн м3. С помощью георадара выявлены и заверены бурением каналы разгрузки подземных вод из аллювия под лед, расположенные в руслах проток. Выявлены геофизические признаки глубинных источников подземных вод в коренных породах. По данным электротомографии установлено наличие крупных и локальных промерзающих подрусловых таликов, из которых выжимается вода на поверхность льда

Twenty-three unsolved problems in hydrology (UPH) – a community perspective

This paper is the outcome of a community initiative to identify major unsolved scientific problems in hydrology motivated by a need for stronger harmonisation of research efforts. The procedure involved a public consultation through on-line media, followed by two workshops through which a large number of potential science questions were collated, prioritised, and synthesised. In spite of the diversity of the participants (230 scientists in total), the process revealed much about community priorities and the state of our science: a preference for continuity in research questions rather than radical departures or redirections from past and current work. Questions remain focussed on process-based understanding of hydrological variability and causality at all space and time scales. Increased attention to environmental change drives a new emphasis on understanding how change propagates across interfaces within the hydrological system and across disciplinary boundaries. In particular, the expansion of the human footprint raises a new set of questions related to human interactions with nature and water cycle feedbacks in the context of complex water management problems. We hope that this reflection and synthesis of the 23 unsolved problems in hydrology will help guide research efforts for some years to come

American Shoulder and Elbow Surgeons Standardized Assessment Form: Russian Cross-Cultural Adaptation and Validation

American Shoulder and Elbow Surgeons Standardized Assessment Form (ASES) is one of the most widely used shoulder outcome reporting measure. However, it has not been validated in the Russian language. Purpose of this study is a cross-cultural adaptation and validation of the ASES. Materials and methods. The group of 93 patients with various shoulder pathology (39 males and 54 females) with median age of 49 years was included into the study. In the first stage the authors performed language and cultural adaptation of the ASES questionnaire to obtain a Russian version maximally matching the original. Further the authors studied the psychometric properties of the questionnaire (reliability, validity, responsiveness), the effects of maximum and minimum values (floor and ceiling effects) and estimated the coefficients of internal consistency of Cronbach’s alpha and reproducibility. 20 patients were selected to assess reproducibility by test-retest method, those patients filled out the ASES questionnaire at first appointment with an orthopedic trauma surgeon and repeatedly in 7 days; the obtained data was evaluated by an intra-class correlation coefficient (ICC). In the framework of the present research the authors assessed the validity of the obtained scale, including the correlation of the scores of the examined questionnaire with the scores by the DASH questionnaire validated in the Russian Federation to check criteria validity. Results. The study resulted in obtaining the assessment scale fully matching the original ASES version with minor linguistic and cultural features. The ASES median results was Me = 68.7 [32.6; 93.8]; no maximum and minimum scores were obtained. The Russian version of the questionnaire has good psychometric properties with internal consistency of Cronbach alpha 0.72. The overall intra-class correlation coefficient (ICC) of the ASES questionnaire was 0.95 (p<0.05). There were no statistically significant differences between the general group and the test-retest group by gender, age and type of shoulder pathology. Correlation coefficient obtained in the scope of the present research between the ASES and DASH scales was 0.9, and the GRI index was 2.8. Conclusion. Russian version of the ASES questionnaire has good psychometric properties and may be recommended to evaluate functional status of patients with shoulder joint pathology and treatment dynamics

Magnetic Resonance Imaging Identification of Rotator Cuff Pathology: Inter-rater Realibilty

Background. The shoulder MRI is one of the main methods for the rotator cuff injuries diagnostics and determination of the further treatment tactics. The agreement in the MRI data interpretation among specialists regarding different types of shoulder ruptures is an integral part of diagnostic test validity evaluation. The purpose of this study was to assess the agreement in the MRI data interpretation in the patients with shoulder rotator cuff pathology among trauma surgeons, as well as between trauma surgeons and a radiologist. Materials and Methods. The study was a retrospective analysis of the MRI data and surgical reports regarding 57 patients with various shoulder pathologies undergone the shoulder MRI and arthroscopic shoulder revisions in the period from 2017 to 2019. There were 38 (67%) men and 19 (33%) women among the patients. The average age of the patients was 52.7±13.6 years. The sensitivity and specificity, as well as the shoulder MRI inter-rater reliability were assessed in the course of the study. Results. The rotator cuff pathology was revealed in 52 patients: supraspinatus tendon injury in 98% of cases, supraspinatus and infraspinatus tendon — in 26%, isolated subscapularis tendon injury — in 2%, supraspinatus and subscapularis tendon — in 39%. The maximal concordance in the MRI data interpretation was achieved in the patients with full-thickness supraspinatus tendon rupture, as well as with the supraspinatus tendon calcifications. However, significant disagreement was found between orthopedists with different work experience in determination of the presence and type of infraspinatus and subscapularis tendons pathology and supraspinatus tendon incomplete ruptures and tendinitis. Conclusion. The high agreement in the MRI data interpretation in determining the pathology of the shoulder rotator cuff among trauma surgeons, as well as between trauma surgeons and radiologists, was observed only regarding the supraspinatus tendon, calcifying tendonitis and full-thickness injury. The diagnosis of tendinitis and incomplete tendon rupture remains difficult. Their interpretation results vary greatly. It is also worth noting the heterogeneity of the results of diagnostics of the infraspinatus and subscapularis tendon pathology