Technical modification of the Metamax II portable metabolic analyser for operation with a breathing apparatus

The O2 uptake of firefighters working in hot and polluted environment is not known. The portable Metamax II might measure the O2 uptake of firefighters using a breathing apparatus. However, the Metamax requires an inspiration signal between two expirations to work properly. When a firefighter inspires from bottles with pressurised air, the inspired air cannot readily be passed through a metabolic analyser. Expired air is on the other hand released to the surroundings and may be sampled for further analyses. In addition, the Metamax II does not tolerate heat, and gases at the scene of fire may damage its delicate sensors. We have modified the Metamax II, producing an artificial inspiration signal after every expiration. We have also protected the instrument from heat at the scene of fire. Expired air was sampled from exercising subjects using a breathing apparatus. The Metamax II instrument was run in the normal and modified modes while the instrumentʼs reported O2 uptake was recorded. Control experiments showed that without an inspiration signal, the instrument did not work reliably. In a typical experiment the reported O2 uptake was only 50% of the true value. In further experiments an artificial inspiration signal was sent to the main unit after every expiration. Then the instrument worked properly although only expired air passed through the Metamaxʼ breathing valve. With proper modifications of the Metamax II, the instrument worked well even if only expired air passed through the breathing valve. The valve may thus be mounted on the outlet of a firefighterʼs breathing mask. The instrument can readily be protected from heat at the scene of fire and thus be used to measure the O2 uptake of smoke divers during realistic exercises in hot and polluted environments

Anomalous Behavior of the Zero Field Susceptibility of the Ising Model on the Cayley Tree

It is found that the zero field susceptibility chi of the Ising model on the Cayley tree exhibits unusually weak divergence at the critical point Tc. The susceptibility amplitude is found to diverge at Tc proportionally to the tree generation level n, while the behavior of chi is otherwise analytic in the vicinity of Tc, with the critical exponent gamma=0.Comment: 3 pages, 2 figure

Врахування фактору ризику при проведенні поточних валютних операцій

Під час проведення банками операцій поточної купівлі та продажу валюти постає проблема правильної оцінки відкритих довгих валютних позицій. В залежності від зміни курсу банк може мати різні результати від реалізації накопиченої валюти, тобто присутні елементи невизначеності і як її наслідок - валютний ризик. В практичній роботі залишки валюти кожного дня переоцінюються за курсом НБУ. Результати такої переоцінки відображаються за валютним балансом як валютний ризик. Враховуючи це, абсолютно безризиковою буде ситуація, коли кожного дня обсяги купівлі та продажу валюти будуть однакові. Але закрити довгі валютні позиції не завжди вдається. Крім того, проведення валютних операцій практично завжди пов'язане з наявністю певної суми валюти. І ці залишки необхідно враховувати в процесі оцінки ефективності операцій з валютою

Two-Photon Microscopy for Non-Invasive, Quantitative Monitoring of Stem Cell Differentiation

BACKGROUND: The engineering of functional tissues is a complex multi-stage process, the success of which depends on the careful control of culture conditions and ultimately tissue maturation. To enable the efficient optimization of tissue development protocols, techniques suitable for monitoring the effects of added stimuli and induced tissue changes are needed. METHODOLOGY/PRINCIPAL FINDINGS: Here, we present the quantitative use of two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) as a noninvasive means to monitor the differentiation of human mesenchymal stem cells (hMSCs) using entirely endogenous sources of contrast. We demonstrate that the individual fluorescence contribution from the intrinsic cellular fluorophores NAD(P)H, flavoproteins and lipofuscin can be extracted from TPEF images and monitored dynamically from the same cell population over time. Using the redox ratio, calculated from the contributions of NAD(P)H and flavoproteins, we identify distinct patterns in the evolution of the metabolic activity of hMSCs maintained in either propagation, osteogenic or adipogenic differentiation media. The differentiation of these cells is mirrored by changes in cell morphology apparent in high resolution TPEF images and by the detection of collagen production via SHG imaging. Finally, we find dramatic increases in lipofuscin levels in hMSCs maintained at 20% oxygen vs. those in 5% oxygen, establishing the use of this chromophore as a potential biomarker for oxidative stress. CONCLUSIONS/SIGNIFICANCE: In this study we demonstrate that it is possible to monitor the metabolic activity, morphology, ECM production and oxidative stress of hMSCs in a non-invasive manner. This is accomplished using generally available multiphoton microscopy equipment and simple data analysis techniques, such that the method can widely adopted by laboratories with a diversity of comparable equipment. This method therefore represents a powerful tool, which enables researchers to monitor engineered tissues and optimize culture conditions in a near real time manner

Advancing complexity-informed health promotion: a scoping review to link health promotion and co-creation

A complexity-informed approach has recently been proposed as a hopeful revolution for health promotion (HP), requesting appropriate ways of tackling the complexities of health, equity and well-being. In addition, co-creation has gained traction as an approach to tackle complexity. HP and co-creation are established concepts that have long been enacted in practice. Although each concept is premised on similar approaches to value-creation such as participation and collaboration, little has been done to link the two approaches. To advance complexity-informed HP, this scoping review presents findings from peer-reviewed articles, published in English, between 2009 and March 2020. Articles were identified through searches of academic databases. Twenty-seven articles met the inclusion criteria, explicitly linking HP and co-creation. Included articles were charted by descriptive information and main focus, and advanced by a thematic analysis. Four themes suggest a potential avenue for advancing complexity-informed HP: (i) dealing with complexity, (ii) value creation, (iii) the value of the values and (iv) benefits and challenges. While current links between HP and co-creation are scarce they are increasing and promising. Based on the findings from the review, propositions to advance complexity-informed HP is outlined and discussed. Overall it is argued that co-creation and HP are mutually beneficial concepts, providing a framework for participative, collaborative, context-sensitive and knowledge-based practice that reflects the complex nature of health. More research is needed to highlight potential and challenges of integrating co-creation in HP, especially related to health equity and sustainable development