New PC and LabVIEW Based Robot Control System

This paper presents a new economical solution of robot control system for different sophisticated robot applications. The control system is based on PC controlled servo motor control card and an intelligent control software, which has been developed using high level graphical programming language (LabVIEW). The basic development is an interface software for making connection between the control card and LabVIEW. LabVIEW gives a wide range of opportunity of utilisation of the developed control system at different robot applications. This paper shows a complete solution of robot control system for a ZIM 15 (KUKA license) type 6-axis robot. The DDA (Digital Differential Analysis) method and the closed loop control system of the servo motor control card are described. The programming of the control card and the time optimal trajectory planning method are presented, too

Szabadgyök-felszabadulás vizsgálata femtoszekundum lézerrel asszisztált capsulotomiát követően | Evaluation of free radical quantity in the anterior chamber following femtosecond laser-assisted capsulotomy

Absztrakt Bevezetés: A femtoszekundum lézer alkalmazása forradalmi, innovatív kezelési eljárás a szürkehályog-sebészetben. Célkitűzés: Tanulmányunk célja a femtoszekundum lézeres capsulotomia során az elülső csarnokban képződő szabad gyök mennyiségének meghatározása sertésszemben. Módszer: Hetven friss sertésszemet vontunk be a vizsgálatba, amelyeket post mortem 2 órán belül 4 ºC hőmérsékleten szállítottunk, a kezelést pedig 7 órán belül végeztük el. Harmincöt szemet vizsgáltunk a kontroll- és a femtoszekundum lézeres capsulotomia csoportban is. Luminoldependens kemilumineszcens módszer segítségével vizsgáltuk a csarnokvíz szabadgyök-fogó kapacitását, mint a szabadgyök-termelődés indikátorát. Az emittált fotonok mennyiségét relatív fényegység százalékban fejeztük ki. Eredmények: A relatív fényegység százalék alacsonyabb volt a kontrollcsoportban (medián 1%, interkvartilis tartomány 0,4–3%), mint a femtoszekundum lézeres capsulotomia csoportban (medián 4,4%, interkvartilis tartomány 1,5–21%) (p = 0,01). Következtetések: A femtoszekundum lézeres capsulotomia gyengíti a csarnokvíz antioxidáns védelmét, amely a femtoszekundum lézeres capsulotomia során felszabaduló szabad gyökök hatására utal. Orv. Hetil., 2016, 157(47), 1880–1883. | Abstract Introduction: Femtosecond laser is a revolutionary, innovative treatment method used in cataract surgery. Aim: To evaluate free radical quantity in the anterior chamber of the eye, during femtosecond laser assisted capsulotomy, in a porcine eye model. Method: Seventy fresh porcine eyes were collected within 2 hours post mortem, were transported at 4 ºC and treated within 7 hours. Thirty-five eyes were used as control and 35 as femtosecond laser assisted capsulotomy group. A simple luminol-dependent chemiluminescence method was used to measure the total scavenger capacity in the aqueous humour, as an indicator of free radical production. The emitted photons were expressed in relative light unit %. Results: The relative light unit % was lower in the control group (median 1%, interquartile range [0.4–3%]) than in the femtosecond laser assisted capsulotomy group (median 4.4%, interquartile range [1.5%–21%]) (p = 0.01). Conclusions: Femtosecond laser assisted capsulotomy decreases the antioxidant defense of the anterior chamber, which refers to a significant free radical production during femtosecond laser assisted capsulotomy. Orv. Hetil., 2016, 157(47), 1880–1883

Unconventional magnetism in the 4d4^{4} based (S=1S=1) honeycomb system Ag3_{3}LiRu2_{2}O6_{6}

We have investigated the thermodynamic and local magnetic properties of the Mott insulating system Ag$_{3}$LiRu$_{2}$O$_{6}$ containing Ru$^{4+}$ (4$d$$^{4}$) for novel magnetism. The material crystallizes in a monoclinic $C2/m$ structure with RuO$_{6}$ octahedra forming an edge-shared two-dimensional honeycomb lattice with limited stacking order along the $c$-direction. The large negative Curie-Weiss temperature ($\theta_{CW}$ = -57 K) suggests antiferromagnetic interactions among Ru$^{4+}$ ions though magnetic susceptibility and heat capacity show no indication of magnetic long-range order down to 1.8 K and 0.4 K, respectively. $^{7}$Li nuclear magnetic resonance (NMR) shift follows the bulk susceptibility between 120-300 K and levels off below 120 K. Together with a power-law behavior in the temperature dependent spin-lattice relaxation rate between 0.2 and 2 K, it suggest dynamic spin correlations with gapless excitations. Electronic structure calculations suggest an $S = 1$ description of the Ru-moments and the possible importance of further neighbour interactions as also bi-quadratic and ring-exchange terms in determining the magnetic properties. Analysis of our $\mu$SR data indicates spin freezing below 5 K but the spins remain on the borderline between static and dynamic magnetism even at 20 mK.Comment: 10 pages, 11 figures. accepted in Phys. Rev.

Minimizing the stabbing number of matchings, trees, and triangulations

The (axis-parallel) stabbing number of a given set of line segments is the maximum number of segments that can be intersected by any one (axis-parallel) line. This paper deals with finding perfect matchings, spanning trees, or triangulations of minimum stabbing number for a given set of points. The complexity of these problems has been a long-standing open question; in fact, it is one of the original 30 outstanding open problems in computational geometry on the list by Demaine, Mitchell, and O'Rourke. The answer we provide is negative for a number of minimum stabbing problems by showing them NP-hard by means of a general proof technique. It implies non-trivial lower bounds on the approximability. On the positive side we propose a cut-based integer programming formulation for minimizing the stabbing number of matchings and spanning trees. We obtain lower bounds (in polynomial time) from the corresponding linear programming relaxations, and show that an optimal fractional solution always contains an edge of at least constant weight. This result constitutes a crucial step towards a constant-factor approximation via an iterated rounding scheme. In computational experiments we demonstrate that our approach allows for actually solving problems with up to several hundred points optimally or near-optimally.Comment: 25 pages, 12 figures, Latex. To appear in "Discrete and Computational Geometry". Previous version (extended abstract) appears in SODA 2004, pp. 430-43

The clustering of gamma-ray bursts in the Hercules–Corona Borealis Great Wall: the largest structure in the Universe?

The Hercules–Corona Borealis Great Wall is a statistically significant clustering of gamma-ray bursts (GRBs) around redshift 2. Motivated by recent theoretical results indicating that a maximal Universal structure size may indeed coincide with its estimated size (2–3 Gpc), we reexamine the question of this Great Wall’s existence from both observational and theoretical perspectives. Our statistical analyses confirm the clustering’s presence in the most reliable data set currently available, and we present a video showing what this data set looks like in 3D. Cosmological explanations (i.e. having to do with the distribution of gravitating matter) and astrophysical explanations (i.e. having to do with the rate of star formation over cosmic time and space) regarding the origin of such a structure are presented and briefly discussed and the role of observational bias is also discussed at length. This, together with the scientific importance of using GRBs as unique cosmological probes, emphasises the need for future missions such as the THESEUS satellite, which will provide us with unprecedentedly homogeneous data of GRBs with measured redshifts. We conclude from all this that the Hercules–Corona Borealis Great Wall may indeed be the largest structure in the Universe – but to be able to decide conclusively whether it actually exists, we need THESEUS

EZH2 is a sensitive marker of malignancy in salivary gland tumors

BACKGROUND: The immunohistochemical detection of Enhancer of zeste homologue 2 (EZH2) proved to be a useful tool to recognize the malignant nature of tumors in a wide variety of neoplasms. The histological diagnostics of salivary gland tumors is a challenging task, and a reliable marker of malignancy would be extremely helpful. METHODS: EZH2 expression was investigated in 54 malignant and 40 benign salivary gland tumors of various histological types by standard immunohistochemistry. RESULTS: The majority (n = 52) of the malignant tumors stained positively, while all the investigated benign tumors were negative for EZH2. CONCLUSIONS: EZH2 expression in salivary gland tumors, similarly to the tumors of other organs is not characteristic for any tumor type, but is a solid marker of the malignant nature of the tumors