166 research outputs found
Probing the ZZgamma and Zgammagamma Couplings Through the Process e+e- --> nu anti-nu gamma
We study the sensitivity for testing the anomalous triple gauge couplings
and via the process
at high energy linear colliders. For integrated luminosities of 500
and center of mass energies between 0.5 and 1.5 , we find that this
process can provide tests of the triple neutral gauge boson couplings of order
, one order of magnitude lower than the standard model prediction.Comment: 12 pages, 6 figure
Scanning Electron Microscope Study of Wohlfahrtia magnifica (Schiner, 1862) (Diptera: Sarcophagidae) I. Structures with Parasitic and Possible Taxonomic Meaning
The larval development of Wohlfahrtia magnifica (the most important dipteran causing sheep myiasis in the Palearctic region) has been studied by means of scanning electron microscopy. The ultrastructure of mouth-hooks, oral ridges, labial lobes, body spines and anterior and posterior peritremes is described for the first time. Their possible adaptations to a parasitic lifeway are also discussed. Thus, the use of new structures in the Sarcophagidae taxonomy is proposed from the point of view of their ultrastructure and adaptative morphology
Direct identification of clinical pathogens from liquid culture media by MALDI-TOF MS analysis
Objectives: We propose using MALDI-TOF MS as a tool for identifying microorganisms directly from liquid cultures after enrichment of the clinical sample in the media, to obtain a rapid microbiological diagnosis and an adequate administration of the antibiotic therapy in a clinical setting.
Methods: To evaluate this approach, a series of quality control isolates were grown in thioglycollate (TG) broth and brain heart infusion (BHI) broth and extracted under four different protocols before finally being identified by MALDI-TOF MS. After establishing the best extraction protocol, we validated the method in a total of 300 liquid cultures (150 in TG broth and 150 in BHI broth) of different types of clinical samples obtained from two tertiary Spanish hospitals.
Results: The initial evaluation showed that the extraction protocol including a 5 minute sonication step yielded 100% valid identifications, with an average score value of 2.305. In the clinical validation of the procedure, 98% of the microorganisms identified from the TG broth were correctly identified relative to 97% of those identified from the BHI broth. In 24% of the samples analysed, growth by direct sowing was only successful in the liquid medium, and no growth was observed in the direct solid agar cultures.
Conclusions: Use of MALDI-TOF MS plus the sonication-based extraction method enabled direct and accurate identification of microorganisms in liquid culture media in 15 minutes, in contrast to the 24 hours of subculture required for conventional identification, allowing the administration of a targeted antimicrobial therapy
Limits on the Dipole Moments of the -Lepton via the Process $e^{+}e^{-}\to \tau^+ \tau^- \gamma in a Left-Right Symmetric Model
Limits on the anomalous magnetic moment and the electric dipole moment of the
lepton are calculated through the reaction at the -pole and in the framework of a left-right symmetric model.
The results are based on the recent data reported by the L3 Collaboration at
CERN LEP. Due to the stringent limit of the model mixing angle , the
effect of this angle on the dipole moments is quite small.Comment: 15 pages, 3 figure
First Report of an OXA-23 Carbapenemase-Producing Acinetobacter baumannii Clinical Isolate Related to Tn2006 in Spain
A carbapenem-resistant Acinetobacter baumannii clinical isolate belonging to European clone II and sequence type 2 was recov-ered from a patient in the Son Espases hospital in Mallorca, Spain. Genetic analysis showed the presence of the bla OXA-23 gene in association with the widely disseminated transposon Tn2006. This is the first reported identification of A. baumannii carrying bla OXA-23 in Spain
Alma Survey Of Circumstellar Disks In The Young Stellar Cluster IC 348
We present a 1.3 mm continuum survey of the young (2-3 Myr) stellar cluster
IC 348, which lies at a distance of 310 pc, and is dominated by low-mass stars
(M 0.1-0.6 M). We observed 136 Class II sources
(disks that are optically thick in the infrared) at 0.8 (200 au) resolution
with a 3 sensitivity of 0.45 mJy (M 1.3
M). We detect 40 of the targets and construct a mm-continuum
luminosity function. We compare the disk mass distribution in IC 348 to those
of younger and older regions, taking into account the dependence on stellar
mass. We find a clear evolution in disk masses from 1 to 5-10 Myr. The disk
masses in IC 348 are significantly lower than those in Taurus (1-3 Myr) and
Lupus (1-3 Myr), similar to those of Chamaleon~I, (2-3 Myr) and Ori
(3-5 Myr) and significantly higher than in Upper Scorpius (510 Myr). About
20 disks in our sample (5 of the cluster members) have estimated
masses (dust gas) 1 M and hence might be the precursors of
giant planets in the cluster. Some of the most massive disks include transition
objects with inner opacity holes based on their infrared SEDs. From a stacking
analysis of the 96 non-detections, we find that these disks have a typical dust
mass of just 0.4 M, even though the vast majority of
their infrared SEDs remain optically thick and show little signs of evolution.
Such low-mass disks may be the precursors of the small rocky planets found by
\emph{Kepler} around M-type stars.Comment: 19 pages, 12 figure
The TWA 3 Young Triple System: Orbits, Disks, Evolution
We have characterized the spectroscopic orbit of the TWA 3A binary and
provide preliminary families of probable solutions for the TWA 3A visual orbit
as well as for the wide TWA 3A--B orbit. TWA 3 is a hierarchical triple located
at 34 pc in the 10 Myr old TW Hya association. The wide component
separation is 1."55; the close pair was first identified as a possible binary
almost 20 years ago. We initially identified the 35-day period orbital solution
using high-resolution infrared spectroscopy which angularly resolved the A and
B components. We then refined the preliminary orbit by combining the infrared
data with a re-analysis of our high-resolution optical spectroscopy. The
orbital period from the combined spectroscopic solution is 35 days, the
eccentricity is 0.63, and the mass ratio is 0.84; although this
high mass ratio would suggest that optical spectroscopy alone should be
sufficient to identify the orbital solution, the presence of the tertiary B
component likely introduced confusion in the blended optical spectra. Using
millimeter imaging from the literature, we also estimate the inclinations of
the stellar orbital planes with respect to the TWA 3A circumbinary disk
inclination and find that all three planes are likely misaligned by at least
30 degrees. The TWA 3A spectroscopic binary components have spectral
types of M4.0 and M4.5; TWA 3B is an M3. We speculate that the system formed as
a triple, is bound, and that its properties were shaped by dynamical
interactions between the inclined orbits and disk.Comment: Accepted to Ap
Bounding the magnetic and electric dipole moments of tau nu from the process e+e- --> nu bar nu gamma in E6 Superstring Models
We obtain bounds on the anomalous magnetic and electric dipole moments of the
tau-neutrino through the reaction at the
-pole in the framework of a Left-Right symmetric model and a class of
inspired models with an additional neutral vector boson . We
use the data collected by the L3 Collaboration at LEP. For the parameters of
the model we consider the mixing angle and
. We find that our bounds are of the same order of
magnitude as those obtained in other extensions of the Standard Model.Comment: 17 pages, 2 figur
A chromosome-level genome assembly enables the identification of the follicule stimulating hormone receptor as the master sex determining gene in the flatfish Solea senegalensis
Sex determination (SD) shows huge variation among fish and a high evolutionary rate, as illustrated by the Pleuronectiformes (flatfishes). This order is characterized by its adaptation to demersal life, compact genomes and diversity of SD mechanisms. Here, we assembled the Solea senegalensis genome, a flatfish of great commercial value, into 82 contigs (614 Mb) combining long- and short-read sequencing, which were next scaffolded using a highly dense genetic map (28,838 markers, 21 linkage groups), representing 98.9% of the assembly. Further, we established the correspondence between the assembly and the 21 chromosomes by using BAC-FISH. Whole genome resequencing of six males and six females enabled the identification of 41 SNP variants in the follicle stimulating hormone receptor (fshr) consistent with an XX / XY SD system. The observed sex association was validated in a broader independent sample, providing a novel molecular sexing tool. Fshr displayed differential gene expression between male and female gonads from 86 days post-fertilization, when the gonad is still an undifferentiated primordium, concomitant with the activation of amh and cyp19a1a, testis and ovary marker genes, respectively, in males and females. The Y-linked fshr allele, which included 24 non-synonymous variants and showed a highly divergent 3D protein structure, was overexpressed in males compared to the X-linked allele at all stages of gonadal differentiation. We hypothesize a mechanism hampering the action of the follicle stimulating hormone driving the undifferentiated gonad toward testis.info:eu-repo/semantics/acceptedVersio
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