Aspects of thionitrites and nitric oxide in chemistry and biology

This thesis is divided into three parts: Part one is comprised of six chapters and provides a topical review of the main aspects of the chemistry and biology of nitric oxide and of thionitrites. The first chapter is a general introduction to the topic. The second chapter reviews the biology of nitric oxide. The third chapter provides a survey of some of the known chemistry of nitric oxide, with particular emphasis on those aspects which might be relevant in biological systems. The fourth chapter describes the biology of thionitrites in relation to NO. The fifth chapter describes in detail the chemistry of thionitrites, emphasising both those aspects which might be of biological importance and those which make the compounds of potential use in organic synthesis. The sixth chapter states the aims of the present project in the context of the current state of the field, as discussed in the preceding sections of the review. Part two describes the work that has been carried out during this thesis and is divided into 6 chapters. The first three chapters describe the initial results of our studies aimed at finding novel potential uses of thionitrites in organic synthesis, focusing on the thermal or photochemically induced addition of thionitrites onto olefins. Chapter 1 describes the synthesis of unsaturated thionitrites. Chapter 2 reports on the intramolecular cyclisation of thionitrites onto alkenes and its applications for the synthesis of episulfides and thiofuran compounds. Chapter 3 examines the inter-molecular version of this reaction, with particular emphasis on reactions involving trityl thionitrite, which was chosen as a model of a stable tertiary thionitrite. This thionitrite has been shown to add very efficiently to alkenes which contain an electron withdrawing or aromatic group and to conjugated dienes. The products obtained are the corresponding α-oximino sulfides. Chapters 4 and 5 describe the results obtained in studies towards achieving a better understanding of the reactivity of thionitrites in biological systems. Chapter 4 provides additional insight into the possible mechanism of NO release from bio-active thionitrites in vivo, by comparison of the biological activity of enantiomeric pairs of thionitrites in simple rat-artery models. On the other hand, the results discussed in Chapter 5 seem to indicate that a direct thionitrite-disulfide exchange reaction in solution systems which model physiological conditions does not take place. Finally, in Chapter 6, a series of overall conclusions have been drawn. Part three provides a formal description of the experimental results and procedures employed throughout this work and is divided into 6 chapters. The first chapter describes the general procedures. The remaining five chapters describe the experimental details corresponding to the work described in Chapters 1 to 5 of the second part

External localization system for mobile robotics

We present a fast and precise vision-based software intended for multiple robot localization. The core component of the proposed localization system is an efficient method for black and white circular pattern detection. The method is robust to variable lighting conditions, achieves sub-pixel precision, and its computational complexity is independent of the processed image size. With off-the-shelf computational equipment and low-cost camera, its core algorithm is able to process hundreds of images per second while tracking hundreds of objects with millimeter precision. We propose a mathematical model of the method that allows to calculate its precision, area of coverage, and processing speed from the camera’s intrinsic parameters and hardware’s processing capacity. The correctness of the presented model and performance of the algorithm in real-world conditions are verified in several experiments. Apart from the method description, we also publish its source code; so, it can be used as an enabling technology for various mobile robotics problems

Ukrainians' EU migration prospects. OSW Commentary No. 128, 10.03.2014.

The political crisis in Ukraine, particularly the bloodshed seen on 18–20 February and the subsequent Russian intervention in Crimea, has sparked fears of another possible wave of immigrants heading to the EU. However, the country was partially politically stabilised (at least in its central and western parts), and this has made the scenario of a mass migration of people from Ukraine rather unlikely. If there is no civil war in Ukraine, any further development of the political situation in Ukraine may have only an indirect impact on the actual migration. Should the political instability continue, the Ukrainian economy remain in recession while jobs are available for Ukrainian immigrants in the EU, then an increase in the migration of Ukrainian citizens to the EU, including Poland, would be possible. In the short term there may be two characteristic groups of immigrants: (1) young people who will attempt to leave Ukraine for good due to the lack of job opportunities; (2) circulating migrants, mainly from western Ukraine, who will be looking for temporary jobs. Only if the economic downturn trend and political turmoil in Ukraine continues for a longer time, will settlement migration increase

WhyCon: an efficient, marker-based localization system

We present an open-source marker-based localization system intended as a low-cost easy-to-deploy solution for aerial and swarm robotics. The main advantage of the presented method is its high computational efficiency, which allows its deployment on small robots with limited computational resources. Even on low-end computers, the core component of the system can detect and estimate 3D positions of hundreds of black and white markers at the maximum frame-rate of standard cameras. The method is robust to changing lighting conditions and achieves accuracy in the order of millimeters to centimeters. Due to its reliability, simplicity of use and availability as an open-source ROS module (http://purl.org/robotics/whycon), the system is now used in a number of aerial robotics projects where fast and precise relative localization is required

Monte Carlo localization for teach-and-repeat feature-based navigation

This work presents a combination of a teach-and-replay visual navigation and Monte Carlo localization methods. It improves a reliable teach-and-replay navigation method by replacing its dependency on precise dead-reckoning by introducing Monte Carlo localization to determine robot position along the learned path. In consequence, the navigation method becomes robust to dead-reckoning errors, can be started from at any point in the map and can deal with the `kidnapped robot' problem. Furthermore, the robot is localized with MCL only along the taught path, i.e. in one dimension, which does not require a high number of particles and significantly reduces the computational cost. Thus, the combination of MCL and teach-and-replay navigation mitigates the disadvantages of both methods. The method was tested using a P3-AT ground robot and a Parrot AR.Drone aerial robot over a long indoor corridor. Experiments show the validity of the approach and establish a solid base for continuing this work

Musicians and non-musicians show different preference profiles for single chords of varying harmonic complexity

The inverted U hypothesis in music predicts that listeners prefer intermediate levels of complexity. However, the shape of the liking response to harmonic complexity and the effect of musicianship remains unclear. Here, we tested whether the relationship between liking and harmonic complexity in single chords shows an inverted U shape and whether this U shape is different for musicians and non-musicians. We recorded these groups’ liking ratings for four levels of harmonic complexity, indexed by their level of acoustic roughness, as well as several measures of inter-individual difference. Results showed that there is an inverted U-shaped relationship between harmonic complexity and liking in both musicians and non-musicians, but that the shape of the U is different for the two groups. Non-musicians’ U is more left-skewed, with peak liking for low harmonic complexity, while musicians’ U is more right-skewed, with highest ratings for medium and low complexity. Furthermore, musicians who showed greater liking for medium compared to low complexity chords reported higher levels of active musical engagement and higher levels of openness to experience. This suggests that a combination of practical musical experience and personality is reflected in musicians’ inverted U-shaped preference response to harmonic complexity in chords

Differential allergen expression in three Tyrophagus putrescentiae strains inhabited by distinct microbiome

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/152656/1/all13921.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/152656/2/all13921_am.pd

Bridging intravenous thrombolysis in patients with atrial fibrillation

Atrial fibrillation; Intravenous thrombolysis; Oral anticoagulationFibrilación auricular; Trombólisis intravenosa; Anticoagulación oralFibril·lació auricular; Trombolisi intravenosa; Anticoagulació oralBackground and purpose: 40% of acute ischemic stroke patients treated by mechanical thrombectomy (MT) have a clinical history of atrial fibrillation (AF). The safety of bridging intravenous thrombolysis (IVT) (MT + IVT) is currently being discussed. We aimed to analyze the interaction between oral anticoagulation (OAC) status or AF with bridging IVT, regarding the occurrence of symptomatic intracranial hemorrhage (sICH) and functional outcome. Materials and Methods: Multicentric observational cohort study (BEYOND-SWIFT registry) of consecutive patients undergoing MT between 2010 and 2018 (n = 2,941). Multinomial regression models were adjusted for prespecified baseline and plausible pathophysiological covariates identified on a univariate analysis to assess the association of AF and OAC status with sICH and good outcomes (90-day modified Rankin Scale score 0–2). Results: In the total cohort (median age 74, 50.6% women), 1,347 (45.8%) patients had AF. Higher admission National Institutes of Health Stroke Scale (NIHSS) score (aOR 1.04 [95% 1.02–1.06], per point of increase) and prior medication with Vitamin K antagonists (VKA) (aOR 2.19 [95% 1.27–3.66]) were associated with sICH. Neither AF itself (aOR 0.71 [95% 0.41–1.24]) nor bridging IVT (aOR 1.08 [0.67–1.75]) were significantly associated with increased sICH. Receiving bridging IVT (aOR 1.61 [95% 1.24–2.11]) was associated with good 90-day outcome, with no interaction between AF and IVT (p = 0.92). Conclusion: Bridging IVT appears to be a reasonable clinical option in selected patients with AF. Given the increased sICH risk in patients with VKA, subgroup analysis of the randomized controlled trials should analyze whether patients with VKA might benefit from withholding bridging IVT.This study was funded by the Bangerter-Rhyner Foundation and the Swiss Academy of Medical Sciences. Open access funding provided by University of Bern

Utjecaj sušenja, prešanja i antioksidansa na prinos i oksidativnu stabilnost hladno prešanih ulja

Investigated were the influence of drying and pressing parameters of rapeseed, sunflower, and safflower seeds on oil yield, as well as antioxidant addition on the oxidative stability of cold pressed oils. The parameters of the oilseeds and cold pressed oils quality (moisture content, iodine value, saponification value, peroxide value, free fatty acids, and insoluble impurities content) were determined using standard methods. In terms of oxidative stability, rosemary, green tea, and pomegranate extracts were used as natural antioxidants, and propyl gallate was used as synthetic antioxidant. The results showed that the moisture content of the oilseeds, as well as nozzle size and electromotor frequency of the press had an effect on the yield of cold pressed oil. By reducing the nozzle size and electromotor frequency, the volume of produced cold pressed oil increased. Rosemary extract effectively increased the oxidative stability of sunflower and safflower oils, and green tea extract increased the stability of rapeseed oil. Greater stabilisation of the tested oils was achieved with the addition of 0.4% of natural antioxidants compared to the addition of 0.2 %. The synthetic antioxidant, propyl gallate, failed to stabilise safflower oil, and unlike the natural antioxidants, it was less protective for rapeseed and sunflower oil.U ovom radu istražen je utjecaj parametara sušenja (temperatura) i prešanja (veličina otvora glave preše, frekvencija elektromotora) sjemena uljane repice, suncokreta i šafranike na prinos ulja te dodatka antioksidansa (prirodnog, sintetičkog) na oksidacijsku stabilnost hladno prešanih ulja. Standardnim metodama određeni su parametri kvalitete uljarica (sadržaj vlage) i hladno prešanih ulja (jodni broj, saponifikacijski broj, peroksidni broj, slobodne masne kiseline, vlaga i sadržaj netopljivih nečistoća). Što se tiče oksidacijske stabilnosti, kao prirodni antioksidansi upotrijebljeni su ekstrakti ružmarina, zelenog čaja i nara, a kao sintetski propil galat. Rezultati su pokazali da vlažnost uljarica te veličina otvora glave preše i frekvencija elektromotora utječu na iskorištenje hladno prešanog ulja. Smanjenjem veličine otvora glave preše i frekvencije elektromotora povećava se volumen proizvedenog hladno prešanog ulja. Ekstrakt ružmarina učinkovito je povećao oksidacijsku stabilnost ulja suncokreta i šafranike, a ekstrakt zelenog čaja povećao je stabilnost repičina ulja. Veća stabilizacija ispitivanih ulja postignuta je dodatkom 0,4 % prirodnih antioksidansa u odnosu na dodatak od 0,2 %. Sintetski antioksidans propil galat nije stabilizirao ulje šafranike, a za razliku od upotrijebljenih prirodnih antioksidansa, manje štiti repičino i suncokretovo ulje od oksidacije

New sensor to measure the microencapsulated active compounds released in an aqueous liquid media based in dielectric properties in radiofrequency range

[EN] In recent years, the general and scientific interest in nutrition, digestion, and what role they play in our body has increased, and there is still much work to be carried out in the field of developing sensors and techniques that are capable of identifying and quantifying the chemical species involved in these processes. Iron deficiency is the most common and widespread nutritional disorder that mainly affects the health of children and women. Iron from the diet may be available as heme or organic iron, or as non-heme or inorganic iron. The absorption of non-heme iron requires its solubilization and reduction in the ferric state to ferrous that begins in the gastric acid environment, because iron in the ferric state is very poorly absorbable. There are chemical species with reducing capacity (antioxidants) that also have the ability to reduce iron, such as ascorbic acid. This paper aims to develop a sensor for measuring the release of encapsulated active compounds, in different media, based on dielectric properties measurement in the radio frequency range. An impedance sensor able to measure the release of microencapsulated active compounds was developed. The sensor was tested with calcium alginate beads encapsulating iron ions and ascorbic acid as active compounds. The prediction and measurement potential of this sensor was improved by developing a thermodynamic model that allows obtaining kinetic parameters that will allow suitable encapsulation design for subsequent release.This research was funded by Spanish AGENCIA ESTATAL DE INVESTIGACIÓN, grant number PID2020-116816RB-I00.Tomas-Egea, JA.; Fito, PJ.; Colom Palero, RJ.; Castro Giraldez, M. (2021). New sensor to measure the microencapsulated active compounds released in an aqueous liquid media based in dielectric properties in radiofrequency range. Sensors. 21(17):1-15. https://doi.org/10.3390/s21175781S115211