A new method for estimating the pattern speed of spiral structure in the Milky Way

In the last few decades many efforts have been made to understand the effect of spiral arms on the gas and stellar dynamics in the Milky Way disc. One of the fundamental parameters of the spiral structure is its angular velocity, or pattern speed $\Omega_p$, which determines the location of resonances in the disc and the spirals' radial extent. The most direct method for estimating the pattern speed relies on backward integration techniques, trying to locate the stellar birthplace of open clusters. Here we propose a new method based on the interaction between the spiral arms and the stars in the disc. Using a sample of around 500 open clusters from the {\it New Catalogue of Optically Visible Open Clusters and Candidates}, and a sample of 500 giant stars observed by APOGEE, we find $\Omega_p = 23.0\pm0.5$ km s$^{-1}$ kpc$^{-1}$, for a local standard of rest rotation $V_0=220$~km s$^{-1}$ and solar radius $R_0=8.0$~kpc. Exploring a range in $V_0$ and $R_0$ within the acceptable values, 200-240 km s$^{-1}$ and 7.5-8.5 kpc, respectively, results only in a small change in our estimate of $\Omega_p$, that is within the error. Our result is in close agreement with a number of studies which suggest values in the range 20-25 km s$^{-1}$ kpc$^{-1}$. An advantage of our method is that we do not need knowledge of the stellar age, unlike in the case of the birthplace method, which allows us to use data from large Galactic surveys. The precision of our method will be improved once larger samples of disk stars with spectroscopic information will become available thanks to future surveys such as 4MOST.Comment: 10 pages, 6 figures, 4 tables, accepted for publication in MNRA

The Universal Cut Function and Type II Metrics

In analogy with classical electromagnetic theory, where one determines the total charge and both electric and magnetic multipole moments of a source from certain surface integrals of the asymptotic (or far) fields, it has been known for many years - from the work of Hermann Bondi - that energy and momentum of gravitational sources could be determined by similar integrals of the asymptotic Weyl tensor. Recently we observed that there were certain overlooked structures, {defined at future null infinity,} that allowed one to determine (or define) further properties of both electromagnetic and gravitating sources. These structures, families of {complex} `slices' or `cuts' of Penrose's null infinity, are referred to as Universal Cut Functions, (UCF). In particular, one can define from these structures a (complex) center of mass (and center of charge) and its equations of motion - with rather surprising consequences. It appears as if these asymptotic structures contain in their imaginary part, a well defined total spin-angular momentum of the source. We apply these ideas to the type II algebraically special metrics, both twisting and twist-free.Comment: 32 page

A case of infliximab-induced lupus in a patient with ankylosing spondylitis: is it safe switch to another anti-TNF-α agent?

Anti-TNF-α therapies are the latest class of medications found to be associated with drug-induced lupus, a distinctive entity known as anti-TNF-α-induced lupus (ATIL) (Williams et al., Rheumatology (Oxford) 48:716-20, 2009; De Rycke et al., Lupus 14:931-7, 2005; De Bandt et al., Clin Rheumatol 22:56-61, 2003). With the widespread use of these agents, it is likely that the incidence of ATIL will increase. The onset of ATIL in patients with rheumatoid arthritis and Crohn's disease has been described, but the literature regarding the occurrence of this entity in patients with ankylosing spondylitis (AS) is scarce (De Bandt et al., Clin Rheumatol 22:56-61, 2003; Ramos-Casals et al., Autoimmun Rev 9:188-93, 2010; Perez-Garcia et al., Rheumatology 45:114-116, 2006). To our knowledge, few reports of switching anti-TNF-α therapy after ATIL in AS have been reported (Akgül et al., Rheumatol Int, 2012). Therefore, it is not clear whether the development of ATIL should prohibit switch to another therapy, since patients may respond to another anti-TNF-α agent (Akgül et al., Rheumatol Int, 2012; Bodur et al., Rheumatol Int 29:451-454, 2009; Mounach et al., Clin Exp Rheumatol 26:1116-8, 2008; Williams and Cohen, Int J Dermatol 50:619-625, 2011; Ye et al., J Rheumatol 38:1216, 2011; Wetter and Davis, Mayo Clin Proc 84:979-984, 2009; Cush, Clin Exp Rheumatol 22:S141-147, 2004; Kocharla and Mongey, Lupus 18:169-7, 2009). A lack of published experience of successful anti-TNF-α switching is a cause of concern for rheumatologists faced with this challenging clinical scenario. We report the case of a 69-year-old woman with AS who developed infliximab-induced lupus, which did not recur despite the subsequent institution of etanercept. The authors review and discuss ATIL and the possible implications for subsequent treatment with alternative anti-TNF-α agents

Biosecurity and readiness of smallholder pig farmers against potential African Swine Fever outbreak and other pig diseases in Baybay City, Leyte, Philippines

Preventing African Swine Fever (ASF) outbreaks require an active involvement of pig growers as they are in the frontline of detection, notification, and the application of strict biosecurity measures. The Eastern Visayas (Region VIII) in Central Philippines is still free of ASF but the risk can be remarkable given the high volume of pigs that enter in this region as a market hub to large pig producers both coming from Luzon (north) and Mindanao (south). This study was conducted to better understand the readiness and biosecurity practices of smallholder pig farmers who comprise most of the pig growers in the City of Baybay, Leyte. Using multiple correspondence analysis (MCA) and agglomerative hierarchical clustering (AHC) technique of data from 350 pig farmer-respondents, our study found several areas in pig raising activities that need to be highlighted. While pig farmers were generally aware of the threat posed by ASF and have relatively good biosecurity practices, only 32.90% were convinced that the City of Baybay is prepared in the case of an ASF outbreak. Moreover, the importance of vaccination, footbath, and controlling swill feeding need to be emphasized (Cluster 2, 58.29%).  More efforts should be directed towards preparing and training pig farmers on disease monitoring and surveillance and improving further its biosecurity practices with special focus on bioexclusion. Similar studies should be conducted to nearby local government units particularly those located near entry and exit borders of the Eastern Visayas region

Reaction of Capsicum peppers commercialized in the Federal District to bacterial wilt.

To verify the bacterial wilt reaction on Capsicum peppers commercialized in the Federal District (DF), fruits of several genotypes within this genus were collected from six different fairs distributed in the satellite cities of Gama, Sobradinho and Guará

Transgenic fish

Transgenic animal is defined as an animal that has been become transformed following the introduction of a novel gene in to its DNA. Gordon et al (1980) were the first to produce transgenic animals leased on the microinjection of cloned DNA into pronucleus of the fertilized eggs at the arc cell stage. Palmitev et al (1982) INTRODUCED GH gene into mice and achieve dramatic increase in growth of the animals and the successful transgenic animal has been produced

Analytic estimates for penguin operators in quenched QCD

Strong penguin operators are singlets under the right-handed flavor symmetry group SU(3)_R. However, they do not remain singlets when the operator is embedded in (partially) quenched QCD, but instead they become linear combinations of two operators with different transformation properties under the (partially) quenched symmetry group. This is an artifact of the quenched approximation. Each of these two operators is represented by a different set of low-energy constants in the chiral effective theory. In this paper, we give analytic estimates for the leading low-energy constants, in quenched and partially quenched QCD. We conclude that the effects of quenching on Q_6 are large.Comment: 6 pages. Typo fixed and an explanatory footnote adde

Transmission of viruses via our microbiomes.

BackgroundBacteria inhabiting the human body have important roles in a number of physiological processes and are known to be shared amongst genetically-related individuals. Far less is known about viruses inhabiting the human body, but their ecology suggests they may be shared between close contacts.ResultsHere, we report the ecology of viruses in the guts and mouths of a cohort and demonstrate that substantial numbers of gut and oral viruses were shared amongst genetically unrelated, cohabitating individuals. Most of these viruses were bacteriophages, and each individual had distinct oral and gut viral ecology from their housemates despite the fact that some of their bacteriophages were shared. The distribution of bacteriophages over time within households indicated that they were frequently transmitted between the microbiomes of household contacts.ConclusionsBecause bacteriophages may shape human oral and gut bacterial ecology, their transmission to household contacts suggests they could have substantial roles in shaping the microbiota within a household