The Euclid-Mullin graph

We introduce the Euclid-Mullin graph, which encodes all instances of Euclid's proof of the infinitude of primes. We investigate structural properties of the graph both theoretically and numerically; in particular, we prove that it is not a tree.Comment: 24 pages, 2 figures, to appear in Journal of Number Theor

Model-based meta-analysis to optimise S. aureus-targeted therapies for atopic dermatitis

Several clinical trials of Staphylococcus aureus (S. aureus)-targeted therapies for atopic dermatitis (AD) have demonstrated conflicting results regarding whether they improve AD severity scores. This study performs a model-based meta-analysis to investigate possible causes of these conflicting results and suggests how to improve the efficacies of S. aureus-targeted therapies. We developed a mathematical model that describes systems-level AD pathogenesis involving dynamic interactions between S. aureus and Coagulase Negative Staphylococcus (CoNS). Our model simulation reproduced the clinically observed detrimental effects of application of S. hominis A9 (ShA9) and flucloxacillin on AD severity and showed that these effects disappeared if the bactericidal activity against CoNS was removed. A hypothetical (modelled) eradication of S. aureus by 3.0 log10 CFU/cm2, without killing CoNS, achieved comparable EASI-75 to dupilumab. This efficacy was potentiated if dupilumab was administered in conjunction with S. aureus eradication (EASI-75 at week 16; S. aureus eradication: 66.7%, dupilumab 61.6% and combination: 87.8%). The improved efficacy was also seen for virtual dupilumab poor responders. Our model simulation suggests that killing CoNS worsens AD severity and that S. aureus-specific eradication without killing CoNS could be effective for AD patients, including dupilumab poor responders. This study will contribute to design promising S. aureus-targeted therapy

Isolating Triggered Star Formation

Galaxy pairs provide a potentially powerful means of studying triggered star formation from galaxy interactions. We use a large cosmological N-body simulation coupled with a well-tested semi-analytic substructure model to demonstrate that the majority of galaxies in close pairs reside within cluster or group-size halos and therefore represent a biased population, poorly suited for direct comparison to ``field'' galaxies. Thus, the frequent observation that some types of galaxies in pairs have redder colors than ``field'' galaxies is primarily a selection effect. We select galaxy pairs that are isolated in their dark matter halos with respect to other massive subhalos (N=2 halos) and a control sample of isolated galaxies (N=1 halos) for comparison. We then apply these selection criteria to a volume-limited subset of the 2dF Galaxy Redshift Survey with M_Bj <= -19 and obtain the first clean measure of the typical fraction of galaxies affected by triggered star formation and the average elevation in the star formation rate. We find that 24% (30.5%) of these L^\star and sub-L^{\star} galaxies in isolated 50 (30) kpc/h pairs exhibit star formation that is boosted by a factor of >~ 5 above their average past value, while only 10% of isolated galaxies in the control sample show this level of enhancement. Thus, 14% (20 %) of the galaxies in these close pairs show clear triggered star formation. The isolation criteria we develop provide a means to constrain star formation and feedback prescriptions in hydrodynamic simulations and a very general method of understanding the importance of triggered star formation in a cosmological context. (Abridged.)Comment: 12 pages, 10 figures, emulateapj format, accepted by Ap

Spin gating electrical current

We use an aluminium single electron transistor with a magnetic gate to directly quantify the chemical potential anisotropy of GaMnAs materials. Uniaxial and cubic contributions to the chemical potential anisotropy are determined from field rotation experiments. In performing magnetic field sweeps we observe additional isotropic magnetic field dependence of the chemical potential which shows a non-monotonic behavior. The observed effects are explained by calculations based on the $\mathbf{k}\cdot\mathbf{p}$ kinetic exchange model of ferromagnetism in GaMnAs. Our device inverts the conventional approach for constructing spin transistors: instead of spin-transport controlled by ordinary gates we spin-gate ordinary charge transport.Comment: 5 pages, 4 figure

Observations of mortality of fur seals between 1998 and 2005 in Tasmania, Australia

Because of their often close relationship with the human environment, the deaths of marine mammals are often documented, particularly if there are links to anthropogenic influences. Between 1998 and 2005 a total of 504 dead Australian Fur Seals, Arctocephalus pusillus doriferus, and New Zealand Fur Seals, Arctocephalus forsteri, were reported in Tasmanian waters. Ninety individuals (18%) were dependent unweaned pups that had been displaced from their natal colonies. Of the 209 adult or subadult seals for which the cause of death could be ascertained,anthropogenic activities were identified as being responsible for the deaths of 172 individuals (82%), with 112 (53%) associated with fish farms. Most fish farm-related deaths occurred during the winter when adult and subadult seals were away from breeding colonies and seal numbers are highest around farms. The next most common cause of death was from firearms (41 individuals - 20%). Death of adults and subadults by natural causes accounted for 37 animals, or 18% of all deaths for which the cause was identified. Excluding pups, most seals were identified as Australian (80%) or New Zealand fur seals (3%). The remainder (17%) were identified as fur seals but not to species. Males were most common (58%), with only 6% identified as females; the sex of 36% could not be determined. Of the males, 106 (26%) were adults and 98 (24%) were subadults or juveniles

Linked and knotted beams of light, conservation of helicity and the flow of null electromagnetic fields

Maxwell's equations allow for some remarkable solutions consisting of pulsed beams of light which have linked and knotted field lines. The preservation of the topological structure of the field lines in these solutions has previously been ascribed to the fact that the electric and magnetic helicity, a measure of the degree of linking and knotting between field lines, are conserved. Here we show that the elegant evolution of the field is due to the stricter condition that the electric and magnetic fields be everywhere orthogonal. The field lines then satisfy a `frozen field' condition and evolve as if they were unbreakable filaments embedded in a fluid. The preservation of the orthogonality of the electric and magnetic field lines is guaranteed for null, shear-free fields such as the ones considered here by a theorem of Robinson. We calculate the flow field of a particular solution and find it to have the form of a Hopf fibration moving at the speed of light in a direction opposite to the propagation of the pulsed light beam, a familiar structure in this type of solution. The difference between smooth evolution of individual field lines and conservation of electric and magnetic helicity is illustrated by considering a further example in which the helicities are conserved, but the field lines are not everywhere orthogonal. The field line configuration at time t=0 corresponds to a nested family of torus knots but unravels upon evolution

Noncoding RNAs and gene silencing

Noncoding RNA has long been proposed to control gene expression via sequence-specific interactions with regulatory regions. Here, we review the role of noncoding RNA in heterochromatic silencing and in the silencing of transposable elements (TEs), unpaired DNA in meiosis, and developmentally excised DNA. The role of cotranscriptional processing by RNA interference and by other mechanisms is discussed, as well as parallels with RNA silencing in imprinting, paramutation, polycomb silencing, and X inactivation. Interactions with regulatory sequences may well occur, but at the RNA rather than at the DNA level

HUBUNGAN ANTARA SUPERVISI DAN KEAMANAN KERJA DENGAN KINERJA PERAWAT DI RUANG RAWAT INAP RSUD NOONGAN

Supervisi dan Keamanan kerja sangat berpengaruh terhadap kinerja dari perawat. Kinerja perawat sebagai ujung tombak pelayanan kesehatan merupakan masalah yang sangat penting untuk dikaji dalam rangka mempertahankan dan meningkatkan mutu pelayanan kesehatan. Kinerja perawat yang baik merupakan jembatan dalam menjawab jaminan kualitas pelayanan kesehatan yang di berikan terhadap pasien baik yang sakit maupun sehat.Tujuan penelitian I ni untuk mengetahui hubungan antara supervise dan keamanan kerja dengan kinerja perawat di ruang rawat inap RSUD Noongan. Metode penelitian ini adalah survei analitik dengan rancangan cross sectional study (studi potong lintang). Populasi dalam penelitian ini adalah 82 perawat.Alat ukur yang digunakan adalah kuesioner. Hasil penelitian ini menunjukkan terdapat hubungan yang signifikan dari masing-masing variable yaitu supervise dan keamanan kerja dengan kinerja perawat. Kesimpulan terdapat hubungan antara supervise dan keamanan kerja dengan kinerja perawat di ruang rawat inap RSUD Noongan. Disanrankan kepada pihak rumah sakit untuk terus meningkatkan supervise dan keamanan kerja dari perawat dan melaksanakan tugas dang tanggung jawab sesuai prosedur yang ada agar tercipta kinerja yang baik. Kata Kunci: Supervisi, Keamanan Kerja dan Kinerja Perawat ABSTRACTSupervision and job security greatly affect the performance of nurses. The performance of nurses as the spearhead of health services is a very important problem to be studied in order to maintain and improve the quality of health services. A good nurse's performance is a bridge in answering the quality assurance of health services provided to patients both sick and healthy. The purpose of this study was to determine the relationship between supervision and work security with the performance of nurses in the inpatient ward of Noongan Hospital. The method of this study was an analytical survey with a cross sectional study design. The population in this study were 82 nurses. The measuring instrument used is a questionnaire. The results of this study indicate that there is a significant relationship of each variable, namely supervision and job security with nurse performance. Conclusion there is a relationship between supervision and job security with the performance of nurses in the inpatient ward of Noongan Hospital. Disseminated to the hospital to continue to improve supervision and work security of nurses and carry out the duties and responsibilities in accordance with existing procedures in order to create good performance. Keywords: Supervision, Work Security and Nurse Performance

DESIRABILITY OF CHEMICAL DECLADDING FROM THE WASTE DISPOSAL VIEWPOINT

Chemical decladding of stainless-steel- and Zircaloyjacketed fuel elements is discussed relative to cladding activation and waste-disposal cost as compared with a total dissolution process. (C.J.G.