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Ana Damjanovic, Ada Y Chen, R. Rosenberg, D. Roe, Xiongwu Wu, B. Brooks

The selectivity filter (SF) of bacterial voltage‐gated sodium channels consists of four glutamate residues arranged in a C4 symmetry. The protonation state population of this tetrad is unclear. To address this question, we simulate the pore domain of bacterial voltage‐gated sodium channel of Magnetococcus sp. (NavMs) through constant pH methodology in explicit solvent and free energy perturbation calculations. We find that at physiological pH the fully deprotonated as well as singly and doubly protonated states of the SF appear feasible, and that the calculated pKa decreases with each additional bound ion, suggesting that a decrease in the number of ions in the pore can lead to protonation of the SF. Previous molecular dynamics simulations have suggested that protonation can lead to a decrease in the conductance, but no pKa calculations were performed. We confirm a decreased ionic population of the pore with protonation, and also observe structural symmetry breaking triggered by protonation; the SF of the deprotonated channel is closest to the C4 symmetry observed in crystal structures of the open state, while the SF of protonated states display greater levels of asymmetry which could lead to transition to the inactivated state which possesses a C2 symmetry in the crystal structure. We speculate that the decrease in the number of ions near the mouth of the channel, due to either random fluctuations or ion depletion due to conduction, could be a self‐regulatory mechanism resulting in a nonconducting state that functionally resembles inactivated states.

G. Zhikhareva, M. Kramm, O. Bodin, R. Seepold, N. M. Madrid, A. Chernikov, Y. Kupriyanova, N. A. Zhuravleva

The actual task of electrocardiographic examinations is to increase the reliability of diagnosing the condition of the heart. Within the framework of this task, an important direction is the solution of the inverse problem of electrocardiography, based on the processing of electrocardiographic signals of multichannel cardio leads at known electrode coordinates in these leads (Titomir et al. Noninvasiv electrocardiotopography, 2003), (Macfarlane et al. Comprehensive Electrocardiology, 2nd ed. (Chapter 9), 2011). In order to obtain more detailed information about the electrical activity of the heart, we carry out a reconstruction of the distribution of equivalent electrical sources on the heart surface. In this area, we hold reconstruction of the equivalent sources during the cardiac cycle at relatively low hardware cost. ECG maps of electrical potentials on the surface of the torso (TSPM) and electrical sources on the surface of the heart (HSSM) were studied for different times of the cardiac cycle. We carried out a visual and quantitative comparison of these maps in the presence of pathological regions of different localization. For this purpose we used the model of the heart electrical activity, based on cellular automata. The model of cellular automata allows us to consider the processes of heart excitation in the presence of pathological regions of various sizes and localization. It is shown, that changes in the distribution of electrical sources on the surface of the epicardium in the presence of pathological areas with disturbances in the conduction of heart excitation are much more noticeable than changes in ECG maps on the torso surface.

M. Simić, Vladan Stojnić, V. Starčević, Z. Babić, J. Filipi

Although there are plenty of commercial systems dedicated to measuring environmental parameters, because of need for specific parameters of interest (temperature, relative humidity, atmospheric pressure, ultraviolet light level, infrared light level and visible light level, micro-sized particles concentrations, magnetic flux density, and wind speed) we proposed a multi-sensors and low-cost platform designed for remote monitoring of environmental conditions on a bee yard. The proposed system has specific features such as portability, battery-power supply, and unit for transmitting data to the remote server. Initial testing showed ability of the system to process all data on time and to perform reliable acquisition.

Drazen Brdjanin, Č. Zeljković, Nemanja Kitić, D. Banjac, Ivana Stakic, Cedomir Susnjar, Ranko Gavric, Nikola Vidovic et al.

The paper presents an online web-oriented system named SOLARS, which is aimed at calculating the feasibility of building the photovoltaic (PV) systems. SOLARS currently enables potential investors to calculate the technical and financial feasibility of building the PV systems in the Republic of Srpska (Bosnia and Herzegovina). Very intuitive GUI design enables investors to obtain feasibility calculations in three simple steps: (i) selection of a geographical location, (ii) specification of technical parameters, and (iii) specification of financial parameters. A usage scenario is illustrated by a real feasibility calculation example.

Postural orthostatic tachycardia syndrome (POTS) is a chronic, debilitating condition characterized by heterogeneous symptoms, such as lightheadedness, palpitations, pre-syncope, syncope, and weakness or heaviness, especially of the legs. It is frequently associated with hypermobile joints or conditions such as chronic fatigue syndrome, chronic abdominal pain, migraine headache, and diabetes mellitus. Described is a case of POTS, which though it is not rare, is rarely diagnosed. It can be diagnosed quickly with simple methods.

Oliver Feeney, G. Werner-Felmayer, H. Siipi, Markus Frischhut, S. Zullo, Ursela Barteczko, Lars Øystein Ursin, S. Linn et al.

The effective collection and management of personal data of rapidly migrating populations is important for ensuring adequate healthcare and monitoring of a displaced peoples' health status. With developments in ICT data sharing capabilities, electronic personal health records (ePHRs) are increasingly replacing less transportable paper records. ePHRs offer further advantages of improving accuracy and completeness of information and seem tailored for rapidly displaced and mobile populations. Various emerging initiatives in Europe are seeking to develop migrant-centric ePHR responses. This paper highlights their importance and benefits, but also identifies a number of significant ethical, legal and social issues (ELSI) and challenges to their design and implementation, regarding (1) the kind of information that should be stored, (2) who should have access to information, and (3) potential misuse of information. These challenges need to be urgently addressed to make possible the beneficial use of ePHRs for vulnerable migrants in Europe.

B. Bebitoğlu, E. Oğuz, Ç. Nuhoğlu, Ayşe Ela Kurtdan Dalkılıç, Pelin Çirtlik, F. Temel, A. Hodzic

Aim: A large number of medications are prescribed in pediatric clinics and this leads to the development of drug–drug interactions (DDI) that may complicate the course of the disease. The aim of the study was to identify the prevalence of potential drug–drug interactions, to categorize main drug classes involved in severe drug–drug interactions and to highlight clinically relevant DDIs in a pediatric population. Material and Methods: A total of 1500 prescriptions during the 12-month study period were retrospectively reviewed; 510 prescriptions that comprised two or more drugs were included in study. The presence of potential drug–drug interactions was identified by using the Lexi-Interact database and categorized according to severity A (unknown), B (minor), C (moderate), D (major), and X (contraindicated). Results: There were 1498 drugs in 510 prescriptions; 253 of these (49.6%) included 2 drugs, 228 (44.7%) included 3–4 drugs, and 29 (5.6%) included ≥5 drugs. A total of 634 (42%) potential drug–drug interactions were idenfied. Among those, 271 (42.7%) were categorized as A, 284 (44.8%) as B, 53 (8.4%) as C, and 26 (4.1%) as D. There was no potential risk for X interaction. Anti-infectives (36%) were the most commonly prescribed drug classes involved in C and/or D categories. Clarithromycin was the most commonly interacting agent that interfered with budesonide. Conclusion: It is noteworthy that a significant number of drugs causing potential drug–drug interactions are prescribed together in pediatric clinics. Increasing the awareness of physicians on this issue will prevent potential complications and ensure patient safety.

J. Dottin, Jabrane Labidi, V. Lekić, M. Jackson, J. Farquhar

Abstract Understanding present-day mantle heterogeneity is key to understanding the geochemical evolution of our planet. The Samoan islands are the type locality for the Enriched Mantle (II) reservoir that is thought to be produced from the subduction and recycling of marine sediment from upper continental crust. In addition to hosting extreme radiogenic isotope compositions from the EM II reservoir, Samoa also exhibits contributions from other mantle reservoirs in a dilute form including the EM (I) (recycled continental material), HIMU (recycled oceanic crust), and DMM (depleted upper mantle) mantle reservoirs. The plume system feeding the Samoan islands sits above a seismically imaged Large Low Shear Velocity Province (LLSVP) and an Ultra-Low Velocity Zone (ULVZ) that is thought to contribute, in addition to recycled components, the recently discovered early-formed (primordial) components with negative μ 182 W and high 3He/4He. Recent work measuring sulfur isotopes in ocean island basalts has established that recycled oceanic and continental crust host unique S-isotope compositions that can be identified at various hotspot localities. Here we document previously unknown relationships between Δ 33 S and radiogenic tungsten, helium and lead isotopes from 7 Samoan basalts (from the islands of Ofu, Vailulu'u and Malumalu) that suggest mixing between several endmembers. One, a HIMU influence that has slight positive Δ 33 S and positive δ 34 S; another, related to EM II that has near zero Δ 33 S and positive δ 34 S; a third, which is primordial with negative μ 182 W, high 3He/4He, that has Δ 33 S = 0 and negative δ 34 S. From this, we conclude that the indistinguishable Δ 33 S of the primordial endmember from that of the convective mantle indicates that sulfur isotopes were homogenized early in Earth's history. The Vailulu'u sample with HIMU characteristics, carries a small but resolvable Δ 33 S that allows, but does not require mass-independent Archean Δ 33 S to shift the Δ 33 S. The observed correlations involving Δ 33 S support arguments linking Pb, He, and W geochemistry to a deep mantle process and places constraints on questions related to the sources of mantle geochemical heterogeneity.

K. Izquierdo, V. Lekić, L. Montési

S U M M A R Y Inversions of planetary gravity are aimed at constraining the mass distribution within a planet or moon. In many cases, constraints on the interior structure of the planet, such as the depth of density anomalies, must be assumed a priori, to reduce the non-uniqueness inherent in gravity inversions. Here, we propose an alternative approach that embraces the non-uniqueness of gravity inversions and provides a more complete view of related uncertainties. We developed a Transdimensional Hierarchical Bayesian (THB) inversion algorithm that provides an ensemble of mass distribution models compatible with the gravitational field of the body. Using this ensemble of models instead of only one, it is possible to quantify the range of interior parameters that produce a good fit to the gravity acceleration data. To represent the interior structure of the planet or moon, we parametrize mass excess or deficits with point masses. We test this method with synthetic data and, in each test, the algorithm is able to find models that fit the gravity data of the body very well. Three of the target or test models used contain only point mass anomalies. When all the point mass anomalies in the target model produce gravity anomalies of similar magnitudes and the signals from each anomaly are well separated, the algorithm recovers the correct location, number and magnitude of the point mass anomalies. When the gravity acceleration data of a model is produced mostly by a subset of the point mass anomalies in the target model, the algorithm only recovers the dominant anomalies. The fourth target model is composed of spherical caps representing lunar mass concentration (mascons) under major impact basins. The algorithm finds the correct location of the centre of the mascons but fails to find their correct outline or shape. Although the inversion results appear less sharp than the ones obtained by classical inversion methods, our THB algorithm provides an objective way to analyse the interior of planetary bodies that includes epistemic uncertainty.

T. Hurford, W. Henning, R. Maguire, V. Lekić, N. Schmerr, M. Panning, V. Bray, M. Manga et al.

Edvin Teskeredzic, Kenan Karahodžić, N. Nosovic

In this paper, three variants of the Floyd-Warshall (FW) All Pairs Shortest Path (APSP) algorithm are presented and compared - the sequential implementation, the parallel implementation using the Nvidia CUDA API, and the blocked parallel version of the FW algorithm. A performance analysis between these three approaches, as well as between the individual phases of the parallel algorithm is provided. The performance of these algorithms has been measured on regular as well as on embedded GPU hardware, and a significant speedup has been achieved. Additionally, this paper shows that a blocked data access results in significant energy savings of up to 72% on embedded hardware.

Summary Background/Aim: Potentially malignant oral lesions (PMOL) are lesions that have an increased risk of malignant transformation concerning healthy oral mucosa. This research aimed to assess the knowledge of students of final years of study on the potentially malignant lesions of the oral cavity. Material and Methods: 120 students of the fourth and fifth years of study participated in this research,60 respondents were fourth-year students, 60 respondents were fifth-year students. All of the respondents signed informed consent.According to the type of research, this is a cross-sectional study which was conducted by completing a 15-item questionnaire. The results were statistically analyzed and processed in the SPSS Statistics 21.0 program. Results: The results indicate that during the clinical examination the fourth and fifth-year students examine the oral mucosa as well. 61% of the students find themselves poorly informed on the PMOL. In the fourth year of study, only 5,5% of students responded that they were well informed, while in the fifth year that number totaled 28,5%. When knowledge self-assessment is concerned the difference has shown itself to be statistically significant between the fourth and fifth-year students. When asked what knowledge on the prevention of oral cancer they expect to receive during their studies, 78% of the students expected more knowledge than at that moment – 36% of which were fifth-year students, and 42% were fourth-year students. Conclusions: Even though the oral cavity is easily accessible to examination, the discovery of oral cancer occurs quite late. Ours, as well as results of other studies, impose the need for better theoretical and practical education of the students.

Nermin Hrustic, N. Prljaca

This work studies hardware and software aspects concerning the implementation and the performance evaluation of a fast real-time embedded Model Predictive Control (MPC). This study is carried out using a low cost and a low power off-the-shelf high performance embedded computing platform (ARM Cortex M) and an off-the-shelf generic embedded MPC software implementation, with a general purpose QP (quadratic programming) solver (MATLAB). As an example, two oscillating masses system subject to input and output constraints is used. Throughout MPC evaluation is done using a hardware-in-the-loop (HIL) experiments, achieving a couple of milliseconds sampling rates.

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