32 research outputs found
ОСОБЕННОСТИ ВОСПРОИЗВОДСТВА РЫБ РЕКИ ОБИ В ЧЕРТЕ ГОРОДА НОВОСИБИРСКА
After constructing Hydro Power Station on the Ob in the area of Novosibirsk, the authors observed that the conditions for reproduction of sturgeons and whitefish were kept. Species and number of young fish in the dam basin was formed by means of young fish migration from the basin. The researchers observed pike perch larvae and bream larvae in the years when low level of water was observed. When high level of water was observed, the authors found the species located in the upper layers of the basin. Nerfling species dominated in the Ob gulfs near the dam. Due to these fish migrating from the reservoir of juveniles and pike-perch larvae from river spawning temporary communities of juveniles are created in the riverbed with the duration of existence from 14 to 33 days. Young fish communities with livability from 14 to 33 days are formed by means of young fish and pike perch migrating from the basin. The maximum number of larvae in the river (0.617-0.703 EQ/m)3 was observed in the 1990s at maximum fish yield in the river and basin. Bream and pike-perch made more than 90% of fish yield. The number of young fish was much higher and equal to 29.9 – 102.7 samples/ m3 in the coastal shallow waters in the area of the spawning grounds. Carp species were mostly observed. The duration of young fish communities livability in the coastal area was 4-5 days more in comparison with that in the basal places. In the last decade, the conditions for fish reproduction in the Ob of Novosibirsk area are getting worse. Lower migration of the young fish from the basin influences its quantitative and specific composition in the river. The authors revealed reducing of young fish in the Ob basin, especially pike perch which is the most valuable commercial species. Low part of young fish migrating from spawning areas is supposed to reduce livability due to lack of conditions for feeding on shallow waters where the larvae are absorbed by pumps and die in the basins of the water consumed.После сооружения ГЭС на р. Оби на её акватории в черте г. Новосибирска сохранились условия для воспроизводства осетровых и сиговых рыб. Видовой и количественный состав молоди на речном участке возле плотины формируется за счет ее миграции из водохранилища. В годы с низким уровнем воды личинки представлены судаком и лещом, при высоком уровне – видами, обитающими в верховьях водохранилища. В заливах р. Оби возле плотины воспроизводятся аборигенные виды с преобладанием язя. За счет этих рыб, мигрирующей из водохранилища молоди и личинок судака от речного нереста создаются временные сообщества молоди в русле реки с продолжительностью существования от 14 до 33 дней. Максимальная численность личинок в реке (0,617–0,703 экз/м) 3 наблюдалась в 1990-х гг. при максимальных уловах рыбы в реке и водохранилище. Более 90 % уловов составляли лещ и судак. На прибрежных мелководьях в районе нерестилищ численность молоди была значительно выше и составляла 29,9–102,7 экз/м 3. Обычно доминировали карповые виды рыб. Длительность существования скоплений молоди в прибрежье, по сравнению с русловыми участками, увеличивается на 4–5 дней. В последнее десятилетие условия воспроизводства рыб на акватории р. Оби в районе г. Новосибирска ухудшаются. На количественный и видовой состав молоди в реке оказывает влияние сокращение ее миграций из водохранилища. Выявлено многократное снижение численности молоди рыб в русле Оби самого ценного промыслового вида – судака. У немногочисленной молоди, покидающей нерестилища, снижается выживаемость из-за отсутствия условий для питания на преобразованных мелководьях, личинки засасываются в насосные агрегаты и массово погибают в объемах потребленной воды
ADAPTIVE MAJORITY PROBLEMS FOR RESTRICTED QUERY GRAPHS AND FOR WEIGHTED SETS
Suppose that the vertices of a graph G are colored with two colors in an unknown way. The color that occurs on more than half of the vertices is called the majority color (if it exists), and any vertex of this color is called a majority vertex. We study the problem of finding a majority vertex (or show that none exists), if we can query edges to learn whether their endpoints have the same or different colors. Denote the least number of queries needed in the worst case by m(G). It was shown by Saks and Werman that m(K-n) = n - b(n) where b(n) is the number of 1's in the binary representation of n. In this paper we initiate the study of the problem for general graphs. The obvious bounds for a connected graph G on n vertices are n - b(n) <= m(G) <= n - 1. We show that for any tree T on an even number of vertices we have m(T) = n - 1, and that for any tree T on an odd number of vertices, we have n - 65 <= m (T) <= n - 2. Our proof uses results about the weighted version of the problem for K-n, which may be of independent interest. We also exhibit a sequence G(n) of graphs with m(G(n)) = n - b(n) such that the number of edges in G(n) is O(nb(n))
Edge Ordered Turan Problems
We introduce the Turan problem for edge ordered graphs. We call a simple graph edge ordered, if its edges are linearly ordered. An isomorphism between edge ordered graphs must respect the edge order. A subgraph of an edge ordered graph is itself an edge ordered graph with the induced edge order. We say that an edge ordered graph G avoids another edge ordered graph H, if no subgraph of G is isomorphic to H. The Turan number ex(<)'(n, H) of a family H of edge ordered graphs is the maximum number of edges in an edge ordered graph on n vertices that avoids all elements of H.We examine this parameter in general and also for several singleton families of edge orders of certain small specific graphs, like star forests, short paths and the cycle of length four
On the possibility to increase sensitivity of diagnostic tests for fixed pulmonary hypertension in heart transplant candidates
Background: Fixed pulmonary hypertension (PH) in heart transplant candidates is a risk factor for right ventricular failure in the postoperative period and early mortality. Patients with fixed PH are not included in the waiting list. Thus, the correct assessment of the pulmonary circulation before the operation affects both clinical management and prognosis. Aim: To reduce the risk of incorrect patient non-inclusion to the waiting list by reduction of false negative test results for PH reversibility.Materials and methods: Fourteen heart transplant candidates were included in this retrospective cohort single center study. Fixed PH with pulmonary vascular resistance (PVR) exceeding 3.5 Wood's units was found in all these patients using right heart catheterization and pulmonary vasoreactivity tests. Initially, these patients had not been put into the waiting list. Pulmonary catheterization was performed in the intensive care unit with a Swan-Ganz catheter and pre-pulmonary thermodilution technique. To perform pulmonary vasoreactivity tests, inhaled iloprost (n = 12) or nitric oxide (n = 2) were used. Subsequently all patients received levosimendan infusion at a dose of 12.5 (0.05–0.2) mg/kg/min, with repeated pulmonary artery catheterization and pulmonary vasoreactivity tests at 72 hours after the infusion. Pulmonary vasoreactivity tests results allowed 13 patients to be included into the waiting list. Heart transplantation was performed in 8 recipients, with postoperative assessment of their hemodynamic and clinical parameters. Data are presented as median [25th percentile; 75th percentile].Results: After the levosimendan infusion, there was a decrease in the pulmonary artery mean pressure from 45 [36; 47] to 29.5 [23; 37] mm Hg (p < 0.01), and in PVR from 6.9 [4.9; 8.9] to 3.6 [2.9; 5.9] Wood's units (p <0.01). In 7 patients, PVR decreased to less than 3.5 Wood's units: the rest of the patients underwent pulmonary vasoreactivity tests. As a result, 13 of 14 patients showed reversible PH and were included into the waiting list. By the date of the manuscript submission, heart transplantation has been performed in 8 patients. Their PVR 6 hours after surgery was 2.2 [2; 3.1] Wood's units; there were no cases of fixed PH and right heart failure. There was a single death associated to a hemorrhagic stroke at day 6 after heart transplantation. The sensitivity of pre-operative pulmonary vasoreactivity tests with the use of levosimendan was 87.5%.Conclusion: Levosimendan infusion may increase the sensitivity of the pulmonary vasoreactivity tests before patients' inclusion into the waiting list for heart transplantation
“It’s Not Just Technology, It’s People”: Constructing a Conceptual Model of Shared Health Informatics for Tracking in Chronic Illness Management
First finding of Baikalian amphipod Micruropus possolskii Sowinsky, 1915 (Amphipoda, Crustacea) in Lake Ladoga
Usability of a Patient Education and Motivation Tool Using Heuristic Evaluation
Background: Computer-mediated educational applications can provide a self-paced, interactive environment to deliver educational content to individuals about their health condition. These programs have been used to deliver health-related information about a variety of topics, including breast cancer screening, asthma management, and injury prevention. We have designed the Patient Education and Motivation Tool (PEMT), an interactive computer-based educational program based on behavioral, cognitive, and humanistic learning theories. The tool is designed to educate users and has three key components: screening, learning, and evaluation. Objective: The objective of this tutorial is to illustrate a heuristic evaluation using a computer-based patient education program (PEMT) as a case study. The aims were to improve the usability of PEMT through heuristic evaluation of the interface; to report the results of these usability evaluations; to make changes based on the findings of the usability experts; and to describe the benefits and limitations of applying usability evaluations to PEMT. Methods: PEMT was evaluated by three usability experts using Nielsen\u27s usability heuristics while reviewing the interface to produce a list of heuristic violations with severity ratings. The violations were sorted by heuristic and ordered from most to least severe within each heuristic. Results: A total of 127 violations were identified with a median severity of 3 (range 0 to 4 with 0 = no problem to 4 = catastrophic problem). Results showed 13 violations for visibility (median severity = 2), 38 violations for match between system and real world (median severity = 2), 6 violations for user control and freedom (median severity = 3), 34 violations for consistency and standards (median severity = 2), 11 violations for error severity (median severity = 3), 1 violation for recognition and control (median severity = 3), 7 violations for flexibility and efficiency (median severity = 2), 9 violations for aesthetic and minimalist design (median severity = 2), 4 violations for help users recognize, diagnose, and recover from errors (median severity = 3), and 4 violations for help and documentation (median severity = 4). Conclusion: We describe the heuristic evaluation method employed to assess the usability of PEMT, a method which uncovers heuristic violations in the interface design in a quick and efficient manner. Bringing together usability experts and health professionals to evaluate a computer-mediated patient education program can help to identify problems in a timely manner. This makes this method particularly well suited to the iterative design process when developing other computer-mediated health education programs. Heuristic evaluations provided a means to assess the user interface of PEMT