Mass accretion rates of clusters of galaxies: CIRS and HeCS

We use a new spherical accretion recipe tested on N-body simulations to measure the observed mass accretion rate (MAR) of 129 clusters in the Cluster Infall Regions in the Sloan Digital Sky Survey (CIRS) and in the Hectospec Cluster Survey (HeCS). The observed clusters cover the redshift range of $0.01<z<0.30$ and the mass range of $\sim 10^{14}-10^{15} {h^{-1}~\rm{M_\odot}}$. Based on three-dimensional mass profiles of simulated clusters reaching beyond the virial radius, our recipe returns MARs that agree with MARs based on merger trees. We adopt this recipe to estimate the MAR of real clusters based on measurements of the mass profile out to $\sim 3R_{200}$. We use the caustic method to measure the mass profiles to these large radii. We demonstrate the validity of our estimates by applying the same approach to a set of mock redshift surveys of a sample of 2000 simulated clusters with a median mass of $M_{200}= 10^{14} {h^{-1}~\rm{M_{\odot}}}$ as well as a sample of 50 simulated clusters with a median mass of $M_{200}= 10^{15} {h^{-1}~\rm{M_{\odot}}}$: the median MARs based on the caustic mass profiles of the simulated clusters are unbiased and agree within $19\%$ with the median MARs based on the real mass profile of the clusters. The MAR of the CIRS and HeCS clusters increases with the mass and the redshift of the accreting cluster, which is in excellent agreement with the growth of clusters in the $\Lambda$CDM model.Comment: 25 pages, 19 figures, 7 table

Skyrmion Lattice in a Chiral Magnet

Skyrmions represent topologically stable field configurations with particle-like properties. We used neutron scattering to observe the spontaneous formation of a two-dimensional lattice of skyrmion lines, a type of magnetic vortices, in the chiral itinerant-electron magnet MnSi. The skyrmion lattice stabilizes at the border between paramagnetism and long-range helimagnetic order perpendicular to a small applied magnetic field regardless of the direction of the magnetic field relative to the atomic lattice. Our study experimentally establishes magnetic materials lacking inversion symmetry as an arena for new forms of crystalline order composed of topologically stable spin states

Komunikasi Antarpribadi Pimpinan dan Pegawai dalam Meningkatkan Motivasi Kerja di Kantor Desa Dayun Kabupaten Siak

A process that will always happen in an institution is a communication process. Through communication process information exchange, ideas and experiences. Communication between leaders and employees must always be honest and built based on trust and open attitude between each other to build spirit dan motivation in work.The purpose of this study to know the openness, empathy, positive behavior, supportive attitude and equality of interpersonal communication of leaders and employees in improving work motivation in the office of Dayun village. This research uses qualitative research method with self disclosure. Subject of research consists of one person leadership, three employees and two people as a supporting informant selected by using purposive sampling technique. This study uses data collection techniques interviews, observation and documentation research.Research results show that (a) openness, leadership and employees always emphasize that every existing and involved line must be open to each other without being covered by each other. (b) empathy, leaders always closer, give attention and feel that is being felt by employees so that employees feel cared for and can improve work motivation. (c) positive behavior, either employees or leaders never arise sespicion. Leaders always apply positive thinking to employees, so that employees can work well and comfortable. (d) supportive attitude, leadership and employees always support each other in any case for the achievement of the goal of providing the best service for community, and (e) equality, the leadership never distinguishes caste any degree between him and his servants. He imposed the same thing to improve work motivation and actieve goals

Postoperative laryngoscopy in thyroid surgery: proper timing to detect recurrent laryngeal nerve injury

BACKGROUND: There is currently a lack of consensus to support the proper timing for postoperative laryngoscopy that is reliable to diagnose recurrent laryngeal nerve palsy (RLNP) after thyroid surgery. The purpose of this study was to investigate the impact of different time intervals of fiber-optic nasolaryngoscopy (FNL) on the diagnosis of RLNP. METHOD: FNL was performed postoperatively at day 0 (T1), at second day post-op (T2), and +2 weeks (T3). For patients with RLNP, repeated examinations were performed at +2 (T4), +6 (T5), and +12 months (T6). RESULTS: Four hundred thirty-four patients appear for postoperative FNL, providing 825 nerves at risk. Permanent RLNP occurred in 0.7%, temporary RLNP in 6.7%. RLNP rate was 6.4% at T1, 6.7% at T2, 4.8% at T3, 2.5% at T4, 0.8% at T5, and 0.7% at T6. Full recovery of vocal cord function was confirmed after rehabilitation in 87.5% of cases at T5 and 89% in T6. T2 was significantly superior to T3 in terms of diagnosis of RLNP (P < 0.05). Of patients at T2, 10.7% did not see any reason to FNL because of their normal voice register. CONCLUSION: FNL is essential for the detection of vocal cord paralysis after thyroidectomy. We report different time evaluation criteria of vocal cord motility with great and significant variability of results. Second day post-op inspection of the larynx (T2) is suggested. Symptomatic voice assessment is insufficient

Ocean Planet or Thick Atmosphere: On the Mass-Radius Relationship for Solid Exoplanets with Massive Atmospheres

The bulk composition of an exoplanet is commonly inferred from its average density. For small planets, however, the average density is not unique within the range of compositions. Variations of a number of important planetary parameters--which are difficult or impossible to constrain from measurements alone--produce planets with the same average densities but widely varying bulk compositions. We find that adding a gas envelope equivalent to 0.1%-10% of the mass of a solid planet causes the radius to increase 5-60% above its gas-free value. A planet with a given mass and radius might have substantial water ice content (a so-called ocean planet) or alternatively a large rocky-iron core and some H and/or He. For example, a wide variety of compositions can explain the observed radius of GJ 436b, although all models require some H/He. We conclude that the identification of water worlds based on the mass-radius relationship alone is impossible unless a significant gas layer can be ruled out by other means.Comment: 5 pages, 3 figures, accepted to Ap

Meiosis progression and donor age affect expression profile of DNA repair genes in bovine oocytes

Several genetic and physiological factors increase the risk of DNA damage in mammalian oocytes. Two critical events are meiosis progression, from maturation to fertilization, due to the extensive chromatin remodelling during genome decondensation and aging which is associated to a progressive oxidative stress. In this work, we studied the transcriptional patterns of three genes, RAD51, APEX-1 and MLH1, involved in DNA repair mechanisms. The analyses were performed by Real-Time quantitative PCR (RT-qPCR) in immature and in vitro matured oocytes collected from 17 ± 3 mo old heifers and 94 ± 20 mo old cows. Batches of 30-50 oocytes for each group (three replicates) were collected from ovarian follicles of slaughtered animals. The oocytes were freed from cumulus cells at the time of follicle removal, or after IVM carried out in M199 supplemented with 10% foetal calf serum, 10 IU LH /ml, 0.1 IU FSH /ml and 1 µg 17β-oestradiol/ml. Total RNA was extracted by Trizol method. The expression of bovine GAPDH gene was used as internal standard, while primers for bovine RAD51, APEX-1 and MLH1 genes were designed from DNA sequences retrieved from GeneBank. Results obtained indicate a clear up-regulation of RAD51, APEX-1 and MLH1 genes after IVM ranging between 2- and 4-fold compared to GV oocytes. However, only RAD51 showed a significant transcript increase between the immature oocytes collected from young and old individuals. This finding candidates RAD51 as gene marker for discriminating bovine immature oocytes in relation to the donor age