Advanced hardware control for seven DOFs robotic arm-neuro arm

In this paper we will implement new hardware control for 7 DOFs (Degrees of freedom) advanced robotic arm research platform (NeuroArm) equipped with various sensors. New hardware platform consists of Nano Pi platform which is used as a PC platform for standard PLC (programmable logic controller's) unit and will replace old system that consists of 7 16-bit ATmega processors. The goal of new PLC which is based on Linux operating system (Debian distribution) that is patched by Xenomai real time system for reducing control response time and better entire system control. Robotic arm is powered by 7 DC motors which are controlled by two PWM4 (Pulse Width Modulation) modules. Position data is acquired from 1kΩ resistive sensors using RI8 (Resistive module) module and from optical quadrature encoders using one DI16 (Digital Input) module. Also other modules PWM4, RI8 and DI16 communicate with PikoAtlas CPU module by I2C bus

Advanced hardware control for seven DOFs robotic arm-neuro arm

In this paper we will implement new hardware control for 7 DOFs (Degrees of freedom) advanced robotic arm research platform (NeuroArm) equipped with various sensors. New hardware platform consists of Nano Pi platform which is used as a PC platform for standard PLC (programmable logic controller's) unit and will replace old system that consists of 7 16-bit ATmega processors. The goal of new PLC which is based on Linux operating system (Debian distribution) that is patched by Xenomai real time system for reducing control response time and better entire system control. Robotic arm is powered by 7 DC motors which are controlled by two PWM4 (Pulse Width Modulation) modules. Position data is acquired from 1kΩ resistive sensors using RI8 (Resistive module) module and from optical quadrature encoders using one DI16 (Digital Input) module. Also other modules PWM4, RI8 and DI16 communicate with PikoAtlas CPU module by I2C bus

Frustrated spin order and stripe fluctuations in FeSe

The charge and spin dynamics of the structurally simplest iron-based superconductor, FeSe, may hold the key to understanding the physics of high temperature superconductors in general. Unlike the iron pnictides, FeSe lacks long range magnetic order in spite of a similar structural transition around 90\,K. Here, we report results of Raman scattering experiments as a function of temperature and polarization and simulations based on exact diagonalization of a frustrated spin model. Both experiment and theory find a persistent low energy peak close to 500cm$^{-1}$ in $B_{1g}$ symmetry, which softens slightly around 100\,K, that we assign to spin excitations. By comparing with results from neutron scattering, this study provides evidence for nearly frustrated stripe order in FeSe.Comment: 12 pages, 12 figure

Contamination of the Šar Mountains Aquatorium – Kosovo with Depleted Uranium

The main objective of this study was to estimate the environmental and health risk of the Šar Mountains (Kosovo) for depleted uranium contamination. The risk assessment of the contamination is needed since, in the spring of 1999, conflict with bombarding took place in the territory of the Western Balkans, during which depleted uranium ammunition was used. In Serbia and Montenegro, such tests were performed; based on them, some territories were decontaminated. Šar Mountains is particularly important as it is one of the few water-rich areas in Kosovo. Therefore, soil and water samples were taken from characteristic places in the Šar Mountains aquatorium. Tests of the samples were performed under well-controlled conditions. The measurement uncertainty was less than 5%. Based on the obtained results, it was concluded that there was no contamination of the Šar Mountains with depleted uranium. This conclusion can be extended to the broader area around the Šar Mountains, as it is a safe area surrounded by high mountains

Managing rail service life

The service life of rails depends especially on the operational loads and speeds on the railway lines, as well as on the rail maintenance policy. There are multiple aspects of rail maintenance optimization. The following article considers optimisation of rail maintenance activities relating to rail head surface condition in order to reduce corrective work on track geometry, as well as to minimize the overall costs for track maintenance. The objects of this research are issues and challenges related to rail and track maintenance in curves on modern conventional railway lines for mixed traffic

Epidemiological, clinical and laboratory characteristics of the measles resurgence in the Republic of Serbia in 2014-2015

The Republic of Serbia is a country with ongoing endemic transmission of measles. The aim of this study is to summarize the main characteristics of the measles resurgence that occurred in Serbia in 2014-2015. The national surveillance data on measles was analysed in relation to the clinical, epidemiological and laboratory data. Between November 2014 and December 2015 a measles resurgence with 420 cases was observed in Serbia. Measles virus was initially introduced by and spread among citizens of Bosnia and Herzegovina with temporary residence in Serbia, before spreading to the resident population. Of the 223 patients with available medical records, 173 (77.6%) were unvaccinated. The overall measles incidence during the outbreak was 5.8/100.000. The highest age-specific incidence rate was recorded in children aged lt = 4 years (25.9/100.000), but most cases (67.9%) were gt = 20 years old. Hospitalization rate was high (32.9%) and included two cases of encephalitis associated with measles. In total, 42 health-care workers and 22 related cases including hospitalized patients (n = 13) contracted measles. The overall percentage of laboratory confirmed cases was 81.7% (n = 343/420). All measles virus sequences except one (D9) belonged to genotype D8, suggesting interruption of transmission after the previous outbreak in 2010-2011 caused by genotype D4 viruses. The growing number of adult patients as compared to previous epidemics, suggests an urgent need for supplementary immunization activities targeting susceptible health care workers, unvaccinated or incompletely vaccinated adults as well as people without vaccination records. The comprehensive investigation of the 2014/2015 measles resurgence will contribute to decisions about appropriate countermeasures to stop the future measles resurgences in Serbia

Upravljanje naponima u šinama na železničkim mostovima

This paper analyses the stresses in continuous welded rails on bridges including the aspect of fatigue of rail steel. Furthermore, it examines the possibility to avoid rail expansion joints, while simultaneously exploiting the permissible stress capacity of the rail profile 60E1. Accordingly, general application of permissible values of pressure and tensilestresses prescribed in the current European standards was critically analysed. Paper includes specific application aspects of the prescribed stress values for railway bridges in Serbia. General algorithm for reducing the stresses due to the vehicle/track/bridge interaction, which is presented in this paper, was developed by the authors. This algorithm includes all essential parameters of the bridge structure and railway superstructure, as well as the influence of climate conditions and railway route design.Ovaj rad analizira napone u kontiunualno zavarenim šinama na mostovima, uključujući aspekt zamora šinskog čelika. Pored toga, ispituje se mogućnost izostavljanja šinskih dilatacionih sprava, uz istovremeno iskorišćenje kapaciteta dozvoljenih napona za profil šine 60E1. U skladu sa tim, kritički je analizirana opšta primena dozvoljenih vrednosti napona pritiska i zatezanja koje su propisane u važećim evropskim standardima. Rad uključuje aspekte posebne primene propisanih vrednosti napona za železničke mostove u Srbiji. U radu je predstavljen opšti algoritam za smanjenje napona usled interakcije vozilo/kolosek/most, koji je razvijen od strane autora. Ovaj algoritam uključuje sve bitne parametre konstrukcije mosta i gornjeg stroja železničke pruge, kao i uticaj klimatskih uslova i projekta trase pruge

GC-MS ANALYSIS OF RAMALINA CAPITATA (ACH.) NYL. EXTRACT

This is the first report on the GC-MS profile of the ether-soluble fraction (ESF) of the methanol extract of the lichen Ramalina capitata (Ach.) Nyl. (Ramalinaceae). The profile was dominated by orcinol (22.9 %) and its monomethyl ether (30.9 %), which accounted for more than a half of the GC-MS analyzable fraction of ESF. Significantly lower amounts of structurally related sparassol (5.8%) and atraric acid (0.9 %) were also detected. Additionally, ESF contained methyl linoleate, methyl linolenate and methyl palmitate (17.3 %, 7.3 % and 5.0 %, respectively). GC-MS ANALIZA EKSTRAKTA LIŠAJA RAMALINA CAPITATA (ACH.) NYL.GC-MS profil etarske frakcije (EF) metanolnog ekstrakta lišaja Ramalina capitata (Ach.) Nyl. (Ramalinaceae), predstavljen je po prvi put. GC-MS profilom su dominirali orcinol (22,9%) i njegov derivat – orcinol monometil etar (30,9%), koji su zajedno sačinjavali polovinu EF isparljive/stabilne pod uslovima GC-MS analize. U značajno manjoj količini su detektovani sparasol (5,8%) i atrarna kiselina (0,9%). Takođe, EF je sadržavao metil-linoleat, metil-linolenat i metil-palmitat (17,3%, 7,3% i 5,0%, redom). HIGHLIGHTSChemical composition of the ether-soluble fraction of the methanol extract of Ramalina capitata was investigated by GC-MS for the first time.Eight compounds were identified representing 97.8%.The most abundant volatiles were orcinol (22.9%) and its monomethyl ether (30.9%).Methyl linoleate was found to be the major ester (17.3%) followed by methyl linolenate (7.3%) and methyl palmitate (5.1%).

Optical conductivity and vibrational spectra of the narrow-gap semiconductor FeGa3_3

Intermetallic narrow-gap semiconductors have been intensively explored due to their large thermoelectric power at low temperatures and a possible role of strong electronic correlations in their unusual thermodynamic and transport properties. Here we study the optical spectra and vibrational properties of $\mathrm{FeGa_3}$ single crystal. The optical conductivity indicates that $\mathrm{FeGa_3}$ has a direct band gap of $\sim 0.7$\,eV, consistent with density functional theory (DFT) calculations. Most importantly, we find a substantial spectral weight also below 0.4~eV, which is the energy of the indirect (charge) gap found in resistivity measurements and ab initio calculations. We find that the spectral weight below the gap decreases with increasing temperature, which indicates that it originates from the impurity states and not from the electronic correlations. Interestingly, we did not find any signatures of the impurity states in vibrational spectra. The infrared and Raman vibrational lines are narrow and weakly temperature dependent. The vibrational frequencies are in excellent agreement with our DFT calculations, implying a modest role of electronic correlations. Narrow M\" ossbauer spectral lines also indicate high crystallinity of the sample

“Soft Protein Corona” as the Stabilizer of the Methionine-Coated Silver Nanoparticles in the Physiological Environment: Insights into the Mechanism of the Interaction

The study of the interactions between nanoparticles (NPs) and proteins has had a pivotal role in facilitating the understanding of biological effects and safe application of NPs after exposure to the physiological environment. Herein, for the first time, the interaction between L-methionine capped silver nanoparticles (AgMet), and bovine serum albumin (BSA) is investigated in order to predict the fate of AgMet after its contact with the most abundant blood transport protein. The detailed insights into the mechanism of interaction were achieved using different physicochemical techniques. The UV/Vis, TEM, and DLS were used for the characterization of the newly formed “entity”, while the kinetic and thermodynamic parameters were utilized to describe the adsorption process. Additionally, the fluorescence quenching and synchronous fluorescence studies enabled the prediction of the binding affinity and gave us insight into the influence of the adsorption on the conformation state of the BSA. According to the best of our knowledge, for the first time, we show that BSA can be used as an external stabilizer agent which is able to induce the peptization of previously agglomerated AgMet. We believe that the obtained results could contribute to further improvement of AgNPs’ performances as well as to the understanding of their in vivo behavior, which could contribute to their potential use in preclinical research studies