The loschmidt index

We study the nodes of the wavefunction overlap between ground states of a parameterdependent Hamiltonian. These nodes are topological, and we can use them to analyze in a unifying way both equilibrium and dynamical quantum phase transitions in multiband systems. We define the Loschmidt index as the number of nodes in this overlap and discuss the relationship between this index and the wrapping number of a closed auxiliary hypersurface. This relationship allows us to compute this index systematically, using an integral representation of the wrapping number. We comment on the relationship between the Loschmidt index and other well-established topological numbers. As an example, we classify the equilibrium and dynamical quantum phase transitions of the XY model by counting the nodes in the wavefunction overlaps

Boundary layer analysis for nonlinear singularly perturbed differential equations

This paper focuses on the boundary layer phenomenon arising in the study of singularly perturbed differential equations. Our tools include the method of lower and upper solutions combined with analysis of the integral equation associated with the class of nonlinear equations under consideration

Инфузия по целевой концентрации

In this article the authors present a brief review of the development of intravenous anesthesia, from its beginnings to today’s widely accepted use of the TCI technique. They explain the theory of TCI based on the pharmacokinetic properties of drugs. They point out undeniable advantages that this technique offers, compared to classical intravenous anesthesia and even inhalational anesthesia. They offer a short description of basic technological characteristics of a TCI pump. At the end of the article they present their own experiences with this technique, with the aim to bring it closer to a wider qualified public. Key words: intravenous anesthesia, total intravenous anesthesia, TCI.В этой статье авторы представляют краткий обзор развития внутривенной анестезии от его начала до сегодняшнего использования техники инфузии по целевой концентрации (ИЦК). Объясняют теорию ИЦК, основанную на фарма-кокинетических свойствах лекарственных средств. Указывают на неоспоримые преимущества, которые эта техника предлагает по сравнению с классической внутривенной анестезией и даже ингаляционной анестезией. Предлагают короткое описание базисных технологических характеристик насоса для инфузии по целевой концентрации. В конце статьи авторы представляют собственный опыт применения этой техники с целью донести ее до более широкого круга компетентных читателей. Ключевые слова: внутривенная анестезия, тотальная внутривенная анестезия, ИЦК

Multi-vessel stenting during primary percutaneous coronary intervention for acute myocardial infarction. A single-center experience

BACKGROUND: Recanalization of the culprit lesion is the main goal of primary angioplasty for acute ST-segment elevation myocardial infarction (STEMI). Patients presenting with acute myocardial infarction and multivessel disease are, therefore, usually subjected to staged procedures, with the primary percutaneous coronary intervention (PCI) confined to recanalization of the infarct-related artery (IRA). Theoretically at least, early relief of stenoses of non-infarct-related arteries could promote collateral circulation, which could help to limit the infarct size. However, the safety and feasibility of such an approach has not been adequately established. METHODS: In this single-center prospective study we examined 73 consecutive patients who had an acute STEMI and at least one or more lesions > or = 70% in a major epicardial vessel other than the infarct-related artery. In the first 28 patients, forming the multi-vessel (MV) PCI group, all lesions were treated during the primary procedure. In the following 45 patients, forming the culprit-only (CO) PCI group, only the culprit lesion was treated during the initial procedure, followed by either planned-staged or ischemia-driven revascularization of the non-culprit lesions. Fluoroscopy time and contrast dye amount were compared between both groups, and patients were followed up for one year for major adverse cardiac events (MACE) and other significant clinical events. RESULTS: The two groups were well balanced in terms of clinical characteristics, number of diseased vessels and angiographic characteristics of the culprit lesion. In the MV-PCI group, 2.51 lesions per patient were treated using 2.96 +/- 1.34 stents (1.00 lesions and 1.76 +/- 1.17 stents in the CO-PCI group, both p < 0.001). The fluoroscopy time increased from 10.3 (7.2-16.9) min in the CO-PCI group to 12.5 (8.5-19.3) min in the MV-PCI group (p = 0.22), and the amount of contrast used from 200 (180-250) ml to 250 (200-300) ml, respectively (p = 0.16). Peak CK and CK-MB were significantly lower in patients of the MV-PCI group (843 +/- 845 and 135 +/- 125 vs 1652 +/- 1550 and 207 +/- 155 U/l, p < 0.001 and 0.01, respectively). Similar rates of major adverse cardiac events at one year were observed in the two groups (24% and 28% in multi-vessel and culprit treatment groups, p = 0.73). The incidence of new revascularization in both infarct- and non-infarct-related arteries was also similar (24% and 28%, respectively, p = 0.73). CONCLUSION: We may state from this limited experience that a multi-vessel stenting approach for patients with acute STEMI and multi-vessel disease is feasible and probably safe during routine clinical practice. Our data suggest that this approach may help to limit the infarct size. However, larger studies, perhaps using drug-eluting stents, are still needed to further evaluate the safety and efficiency of this procedure, and whether it is associated with a lower need of subsequent revascularization and lower costs

Correlation between historical data of the germination test and of the tetrazolium test in coffee seeds by GAMLSS.

In the Brazilian National System of Seeds and Seedlings, coffee seeds are evaluated by the germination or tetrazolium test. However, differences have been observed between the results of these tests in various studies, especially when the seeds have a lower level of quality. Given this situation, the aim of this study was to evaluate the correlation between historical data of results of the germination test and of the tetrazolium test in samples of coffee seeds using Generalized Additive Models for Location, Scale and Shape (GAMLSS). Historical data of results of the germination test and of the tetrazolium test of coffee seeds originating from different cultivars and different crop seasons were used. The zero-or-one inflated beta GAMLSS is suitable for fitting data from the germination test and from the tetrazolium test. The estimate of viability by the tetrazolium test varies according to the germination percentage class. There are greater GAMLSS correlations between the percentages of normal seedlings and of viability in the tetrazolium test for germination values above 70%, and low correlations below this value, showing that evaluation of coffee seeds based only on the tetrazolium test may not correspond to actual physiological performance

Developments in water quality monitoring and management in large river catchments using the Danube River as an example

Effective management of water quality in large rivers requires information on the influence of activities within the catchment (urban and rural) throughout the whole river basin. However, traditional water quality monitoring programmes undertaken by individual agencies normally relate to specific objectives, such as meeting quality criteria for wastewater discharges, and fail to provide information on basin-scale impacts, especially in transboundary river basins. Ideally, monitoring in large international river basins should be harmonised to provide a basin-scale assessment of sources and impacts of human activities, and the effectiveness of management actions. This paper examines current water quality issues in the Danube River basin and evaluates the approach to water quality monitoring in the context of providing information for a basin-wide management plan. Lessons learned from the monitoring programme in the Danube are used to suggest alternative approaches that could result in more efficient generation of water quality data and provide new insights into causes and impacts of variations in water quality in other large international river basins