Десорбция кислорода в пленках ферромолибдата стронция в процессе их политермической обработки

Характер десорбции кислорода в пленках ферромолибдата стронция, синтезированных цитрат-гель методом, изучали в процессе политермического отжига в интервале температур 300–1420 К. Установлено, что величина кислородного индекса зависит от скорости нагрева и не выходит на насыщение при Т = 1420 К. На основе результатов Мёссбауэровской спектроскопии показано, что появление кислородных вакансий и их упорядочение с образованием протяженных дефектов типа плоскостей кристаллографического сдвига приводит к понижению координационного числа и образованию ассоциатов кислородных вакансий

Feasibility, safety and tolerability of accelerated dobutamine stress echocardiography

A continuous infusion of a single high dose of dobutamine has been, recently, suggested as a simple and effective protocol of stress echocardiography. The present study assesses the feasibility, safety, and tolerability of an accelerated dobutamine stress protocol performed in patients with suspected or known coronary artery disease. Two hundred sixty five consecutive patients underwent accelerated dobutamine stress echocardiography: the dobutamine was administered at a constant dose of 50 μg/kg/min for up to 10 minutes. The mean weight-adjusted cumulative dose of dobutamine used was 330 ± 105.24 μg/kg. Total duration of dobutamine infusion was 6.6 ± 2.1 min. Heart rate rose from 69.9 ± 12.1 to 123.1 ± 22.1 beats/min at peak with a concomitant change in systolic blood pressure (127.6 ± 18.1 vs. 167.6 ± 45.0 mmHg). Dobutamine administration produced a rapid increase in heart rate (9.4 ± 5.9 beats/min2). The side effects were similar to those described with the standard protocol; the most common were frequent premature ventricular complexes (21.5%), frequent premature atrial complexes (1.5%) and non sustained ventricular tachycardia (1.5%); among non cardiac symptoms the most frequent were nausea (3.4%), headache (1.1%) and symptomatic hypotension (1.1%). No major side effects were observed during the test. Our data demonstrate that a continous infusion of a single high dose of dobutamine is a safe and well tolerated method of performing stress echocardiography in patients with suspected or known coronary artery disease. This new protocol requires the administration of lower cumulative dobutamine dose than standard protocol and results in a significant reduction in test time

Headwater Streams and Wetlands are Critical for Sustaining Fish, Fisheries, and Ecosystem Services

Headwater streams and wetlands are integral components of watersheds that are critical for biodiversity, fisheries, ecosystem functions, natural resource-based economies, and human society and culture. These and other ecosystem services provided by intact and clean headwater streams and wetlands are critical for a sustainable future. Loss of legal protections for these vulnerable ecosystems would create a cascade of consequences, including reduced water quality, impaired ecosystem functioning, and loss of fish habitat for commercial and recreational fish species. Many fish species currently listed as threatened or endangered would face increased risks, and other taxa would become more vulnerable. In most regions of the USA, increased pollution and other impacts to headwaters would have negative economic consequences. Headwaters and the fishes they sustain have major cultural importance for many segments of U.S. society. Native peoples, in particular, have intimate relationships with fish and the streams that support them. Headwaters ecosystems and the natural, socio-cultural, and economic services they provide are already severely threatened, and would face even more loss under the Waters of the United States (WOTUS) rule recently proposed by the Trump administration

Vessel Shrinkage as a Sign of Atherosclerosis Progression in Type 2 Diabetes : A Serial Intravascular Ultrasound Analysis

OBJECTIVE—The aim of this study was to determine the natural history of vascular remodeling of atherosclerotic plaques in patients with type 2 diabetes and the predictors of vessel shrinkage

Using 2D hierarchical heavy hitters to investigate binary relationships

This chapter presents VHHH: a visual data mining tool to compute and investigate hierarchical heavy hitters (HHHs) for two-dimensional data. VHHH computes the HHHs for a two-dimensional categorical dataset and a given threshold, and visualizes the HHHs in the three dimensional space. The chapter evaluates VHHH on synthetic and real world data, provides an interpretation alphabet, and identifies common visualization patterns of HHHs