We consider the pumping of the 63.2 mu m fine-structure line of neutral O I in the high-redshift intergalactic medium (IGM), in analogy with the Wouthuysen-Field effect for the 21 cm line of cosmic H ...I. We show that the soft UV background at similar to 1300 AA can affect the population levels, and if a significant fraction of the IGM volume is filled with "fossil H II regions" containing neutral O I, then mis can produce a nonnegligible spectral distortion in the cosmic microwave background (CMB). O I from redshift z is seen in emission at (1 + z)63.2 mu m, and in the range 7 < z < 10 produces a mean spectral distortion of the CMB with y = (10 super(-9) to 3 x 10 super(-8))(Z/10 super(-3) Z )(I sub(UV)), where Z is the mean metallicity of the IGM and I sub(UV) is the UV background at 1300 AA in units of 10 super(-20) ergs s super(-1) Hz super(-1) cm super(-2) sr super(-1). A measurement of this signature can trace the metallicity at the end of the dark ages, prior to the completion of cosmic reionization, and is complementary to cosmological 21 cm studies. While future CMB experiments such as Planck could constrain the metallicity to the 10 super(-2) Z l, specifically designed experiments could potentially achieve a detection.
Understanding the pathogenesis of infectious disease requires the examination and successful integration of parameters related to both microbial virulence and host responses. As a practical and ...powerful method to control microbial gene expression, including in vivo, the tetracycline-regulatable system has recently gained the favor of many investigative groups. However, some immunomodulatory effects of the tetracyclines, including doxycycline, could potentially limit its use to evaluate host responses during infection. Here we have used a well-established murine model of disseminated candidiasis, which is highly dependent on both the virulence displayed by the fungal cells and on the host immune status, to validate the use of this system. We demonstrate that the pathogenesis of the wild type C. albicans CAF2-1 strain, which does not contain any tet-regulatable element, is not affected by the presence of doxycycline. Moreover levels of key cytokines, chemokines and many other biomarkers, as determined by multi-analyte profiling, remain essentially unaltered by the presence of the antibiotic during infection. Our results indicate that the levels of doxycycline needed to control the tetracycline regulatable promoter gene expression system have no detectable effect on global host responses during candidiasis. Because tet-regulatable systems are now being increasingly used in a variety of pathogenic microorganisms, these observations have wide implications in the field of infectious diseases.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The synthesis, structural characterization and the successful application of a carbon centered radical derived from 1,3-bisdiphenylene-2-phenylallyl (BDPA), its benzyl alcohol derivative (BA-BDPA), ...as a polarizing agent for Dynamic Nuclear Polarization (DNP) are described. The reported BA-BDPA radical meets all the requirements to become a promising candidate for its use in
in vivo
DNP-NMR experiments: it is soluble in neat 1-
13
Cpyruvic acid, insoluble in the dissolution transfer solvent and is effective as a polarizing agent in fast dissolution DNP-NMR applications, without the need for using glassing agents. Moreover, it enables a simple but effective
in-line
radical filtration to obtain hyperpolarized solutions of 1-
13
Cpyruvic acid free of radicals that offers a better polarization performance.
A pyruvic acid soluble BDPA derivative, BA-BDPA, is a promising candidate as a polarizing agent for
in vivo
DNP.
Following a successful period of data-taking between 2006 and 2011, the Virgo gravitational-wave detector was taken offline for a major upgrade. The changes made to the instrument significantly ...increased the complexity of the control systems and meant that an extended period of commissioning was required to reach a sensitivity appropriate for science data-taking. This commissioning period was completed in July of 2017 and the second-generation Advanced Virgo detector went on to join the Advanced LIGO detectors in the O2 science run in August of the same year. The upgraded detector was approximately twice as sensitive to binary neutron star mergers as the first-generation instrument. During the August 2017 science run, Advanced Virgo detected its first gravitational wave signal, with the binary black hole merger, GW170729. This paper describes the control of the longitudinal degrees of freedom in the Advanced Virgo instrument during the O2 science run and the process that brought the detector from an uncontrolled, non-resonant state to its target working point.
Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with ...historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree species are likely to qualify as globally threatened under International Union for Conservation of Nature (IUCN) Red List criteria. If confirmed, these results would increase the number of threatened plant species on Earth by 22%. We show that the trends observed in Amazonia apply to trees throughout the tropics, and we predict that most of the world's >40,000 tropical tree species now qualify as globally threatened. A gap analysis suggests that existing Amazonian protected areas and indigenous territories will protect viable populations of most threatened species if these areas suffer no further degradation, highlighting the key roles that protected areas, indigenous peoples, and improved governance can play in preventing large-scale extinctions in the tropics in this century.
Microemulsions (MEs) were designed by an innovative rational development, characterized, and used to load up to 20 mM of Tamoxifen citrate (TMX). They were made with acceptable and well-characterized ...excipients for all the routes of administration. Some of their properties, such as nanometric mean size and long stability shelf life, make them interesting drug delivery systems. The results obtained after the in vitro inhibition of estradiol-induced proliferation in MCF-7 breast cancer cells demonstrated a significant effect in cell growth. A decreasing of at least 90% in viable cells was shown after the incubation with MEs containing 20 mM of TMX. Besides, two compositions which loaded 10 mM of drug showed a cytotoxic effect higher than 70%. These results encourage the evaluation of alternative protocols for this drug administration, not only for estrogen receptor (ER) positive tumors, but also for ER negative.
We discuss the effects on the cosmic microwave background (CMB), cosmic infrared background (CIB), and thermal Sunyaev-Zeldovich effect due to the peculiar motion of an observer with respect to the ...CMB rest frame, which induces boosting effects. After a brief review of the current observational and theoretical status, we investigate the scientific perspectives opened by future CMB space missions, focussing on the Cosmic Origins Explorer (CORE) proposal. The improvements in sensitivity offered by a mission like CORE, together with its high resolution over a wide frequency range, will provide a more accurate estimate of the CMB dipole. The extension of boosting effects to polarization and cross-correlations will enable a more robust determination of purely velocity-driven effects that are not degenerate with the intrinsic CMB dipole, allowing us to achieve an overall signal-to-noise ratio of 13; this improves on the Planck detection and essentially equals that of an ideal cosmic-variance-limited experiment up to a multipole ℓsime2000. Precise inter-frequency calibration will offer the opportunity to constrain or even detect CMB spectral distortions, particularly from the cosmological reionization epoch, because of the frequency dependence of the dipole spectrum, without resorting to precise absolute calibration. The expected improvement with respect to COBE-FIRAS in the recovery of distortion parameters (which could in principle be a factor of several hundred for an ideal experiment with the CORE configuration) ranges from a factor of several up to about 50, depending on the quality of foreground removal and relative calibration. Even in the case of sime1 % accuracy in both foreground removal and relative calibration at an angular scale of 1o, we find that dipole analyses for a mission like CORE will be able to improve the recovery of the CIB spectrum amplitude by a factor sime 17 in comparison with current results based on COBE-FIRAS. In addition to the scientific potential of a mission like CORE for these analyses, synergies with other planned and ongoing projects are also discussed.
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