6,172 research outputs found
Gut Flora: In the Treatment of Disease
Gut flora is the largest reservoir of human flora. It is an essential factor in certain pathological disorders, including multisystem organ failure, colon cancer and inflammatory bowel diseases and extraintestinal disorders, such as allergy, asthma and even obesity. Prebiotics and probiotics are known to have a role in prevention or treatment of some diseases. Nevertheless, bacteria have been found to be useful for treating disease and thus promoting human health in a safe and natural way
Photonuclear sum rules and the tetrahedral configuration of He
Three well known photonuclear sum rules (SR), i.e. the Thomas-Reiche-Kuhn,
the bremsstrahlungs and the polarizability SR are calculated for 4He with the
realistic nucleon-nucleon potential Argonne V18 and the three-nucleon force
Urbana IX. The relation between these sum rules and the corresponding energy
weighted integrals of the cross section is discussed. Two additional
equivalences for the bremsstrahlungs SR are given, which connect it to the
proton-neutron and neutron-neutron distances. Using them, together with our
result for the bremsstrahlungs SR, we find a deviation from the tetrahedral
symmetry of the spatial configuration of 4He. The possibility to access this
deviation experimentally is discussed.Comment: 13 pages, 1 tabl
DAzLE: The Dark Ages z (redshift) Lyman-alpha Explorer
DAzLE is an near infrared narrowband differential imager being built by the
Institute of Astronomy, Cambridge, in collaboration with the Anglo-Australian
observatory. It is a special purpose instrument designed with a sole aim; the
detection of redshifted Lyman-alpha emission from star forming galaxies at z>7.
DAzLE will use pairs of high resolution (R=1000) narrowband filters to exploit
low background `windows' in the near infrared sky emission spectrum. This will
enable it to reach sensitivities of ~2E-21 W/m^2, thereby allowing the
detection of z>7 galaxies with star formation rates as low as a few solar
masses per year. The design of the instrument, and in particular the crucial
narrowband filters, are presented. The predicted performance of DAzLE,
including the sensitivity, volume coverage and expected number counts, is
discussed. The current status of the DAzLE project, and its projected timeline,
are also presented.Comment: 11 pages, 7 figures, to appear in Proceedings of SPIE Vol. 5492,
Ground-based Instrumentation for Astronom
Genetic diversity, infection prevalence, and possible transmission routes of Bartonella spp. in vampire bats
Bartonella spp. are globally distributed bacteria that cause endocarditis in humans and domestic animals. Recent work has suggested bats as zoonotic reservoirs of some human Bartonella infections; however, the ecological and spatiotemporal patterns of infection in bats remain largely unknown. Here we studied the genetic diversity, prevalence of infection across seasons and years, individual risk factors, and possible transmission routes of Bartonella in populations of common vampire bats (Desmodus rotundus) in Peru and Belize, for which high infection prevalence has previously been reported. Phylogenetic analysis of the gltA gene for a subset of PCR-positive blood samples revealed sequences that were related to Bartonella described from vampire bats from Mexico, other Neotropical bat species, and streblid bat flies. Sequences associated with vampire bats clustered significantly by country but commonly spanned Central and South America, implying limited spatial structure. Stable and nonzero Bartonella prevalence between years supported endemic transmission in all sites. The odds of Bartonella infection for individual bats was unrelated to the intensity of bat flies ectoparasitism, but nearly all infected bats were infested, which precluded conclusive assessment of support for vector-borne transmission. While metagenomic sequencing found no strong evidence of Bartonella DNA in pooled bat saliva and fecal samples, we detected PCR positivity in individual saliva and feces, suggesting the potential for bacterial transmission through both direct contact (i.e., biting) and environmental (i.e., fecal) exposures. Further investigating the relative contributions of direct contact, environmental, and vector-borne transmission for bat Bartonella is an important next step to predict infection dynamics within bats and the risks of human and livestock exposures
Financial stability, target inflation as a monetary rule and concepts of money policy: Implications for the optimal analysis
In this article, basing on offensive lecturing research articles of famous authors on financial instability and monetary policy, we propose as aim of this paper to discuss the controversial rule vs. discretion in monetary policy and the new institutional framework of inflation targeting as a remedy for inflationary pressures after the cause of the intermediate target of monetary anchors and exchange rate policy, since the year 70's of the last Century. To do this, we treated a literature review in the field, assigning the work of various economists thus handling of monetary policy favors the discretion/rule to the new inflation target strategy in 90's and 2000. We put particular emphasis on the second step of this paper on the possibility of inflation targeting as an anti-inflationary objective defended for its main defendants.Keywords: monetary policy, rule, discretion, financial instability, inflation targeting. JEL Classification: E42, E43, E52, E58
Spectroscopic survey of M--type asteroids
M-type asteroids, as defined in the Tholen taxonomy (Tholen, 1984), are
medium albedo bodies supposed to have a metallic composition and to be the
progenitors both of differentiated iron-nickel meteorites and enstatite
chondrites. We carried out a spectroscopic survey in the visible and near
infrared wavelength range (0.4-2.5 micron) of 30 asteroids chosen from the
population of asteroids initially classified as Tholen M -types, aiming to
investigate their surface composition. The data were obtained during several
observing runs during the years 2004-2007 at the TNG, NTT, and IRTF telescopes.
We computed the spectral slopes in several wavelength ranges for each observed
asteroid, and we searched for diagnostic spectral features. We confirm a large
variety of spectral behaviors for these objects as their spectra are extended
into the near-infrared, including the identification of weak absorption bands,
mainly of the 0.9 micron band tentatively attributed to orthopyroxene, and of
the 0.43 micron band that may be associated to chlorites and Mg-rich
serpentines or pyroxene minerals such us pigeonite or augite. A comparison with
previously published data indicates that the surfaces of several asteroids
belonging to the M-class may vary significantly. We attempt to constrain the
asteroid surface compositions of our sample by looking for meteorite spectral
analogues in the RELAB database and by modelling with geographical mixtures of
selected meteorites/minerals. We confirm that iron meteorites, pallasites, and
enstatite chondrites are the best matches to most objects in our sample, as
suggested for M-type asteroids. The presence of subtle absorption features on
several asteroids confirms that not all objects defined by the Tholen M-class
have a pure metallic composition.Comment: 10 figures, 6 tables; Icarus, in pres
- âŠ