Taxonomic notes on Liptena eketi Bethune-Baker, 1926 and related species (Papilionoidea: Lycaenidae: Poritiinae)

Examination of male genitalia confirms that L. seyboui Warren-Gash & Larsen, 2003 is specifically distinct from L. eketi Bethune-Baker, 1926 and shows that L. kiellandi Congdon & Collins, 1998, whilst close to L. eketi, is also distinct. The subspecies kakamegae Congdon & Collins, 1998 of L. kiellandi is synonymised with the nominate subspecies, and the distribution of the different taxa is clarified

An acute phase protein ready to go therapeutic for sepsis

While APP are well-known inflammation biomarkers, A2MG found in sepsis patients' sera within lipid microparticles is an essential player in the host response to sepsis and has diagnostic as well as therapeutic potentials.image

CO and HI observations of an enigmatic cloud

An isolated HI cloud with peculiar properties has recently been discovered by Dedes, Dedes, & Kalberla (2008, A&A, 491, L45) with the 300-m Arecibo telescope, and subsequently imaged with the VLA. It has an angular size of ~6', and the HI emission has a narrow line profile of width ~ 3 km/s. We explore the possibility that this cloud could be associated with a circumstellar envelope ejected by an evolved star. Observations were made in the rotational lines of CO with the IRAM-30m telescope, on three positions in the cloud, and a total-power mapping in the HI line was obtained with the Nancay Radio Telescope. CO was not detected and seems too underabundant in this cloud to be a classical late-type star circumstellar envelope. On the other hand, the HI emission is compatible with the detached-shell model that we developed for representing the external environments of AGB stars. We propose that this cloud could be a fossil circumstellar shell left over from a system that is now in a post-planetary-nebula phase. Nevertheless, we cannot rule out that it is a Galactic cloud or a member of the Local Group, although the narrow line profile would be atypical in both cases.Comment: Accepted for publication in Astronomy and Astrophysic

Circumstellar HI and CO around the carbon stars V1942 Sgr and V CrB

Context. The majority of stars that leave the main sequence are undergoing extensive mass loss, in particular during the asymptotic giant branch (AGB) phase of evolution. Observations show that the rate at which this phenomenon develops differs highly from source to source, so that the time-integrated mass loss as a function of the initial conditions (mass, metallicity, etc.) and of the stage of evolution is presently not well understood. Aims. We are investigating the mass loss history of AGB stars by observing the molecular and atomic emissions of their circumstellar envelopes. Methods. In this work we have selected two stars that are on the thermally pulsing phase of the AGB (TP-AGB) and for which high quality data in the CO rotation lines and in the atomic hydrogen line at 21 cm could be obained. Results. V1942 Sgr, a carbon star of the Irregular variability type, shows a complex CO line profile that may originate from a long-lived wind at a rate of ~ 10^-7 Msol/yr, and from a young (< 10^4 years) fast outflow at a rate of ~ 5 10^-7 Msol/yr. Intense HI emission indicates a detached shell with 0.044 Msol of hydrogen. This shell probably results from the slowing-down, by surrounding matter, of the same long-lived wind observed in CO that has been active during ~ 6 10^5 years. On the other hand, the carbon Mira V CrB is presently undergoing mass loss at a rate of 2 10^-7 Msol/yr, but was not detected in HI. The wind is mostly molecular, and was active for at most 3 10^4 years, with an integrated mass loss of at most 6.5 10^-3 Msol. Conclusions. Although both sources are carbon stars on the TP-AGB, they appear to develop mass loss under very different conditions, and a high rate of mass loss may not imply a high integrated mass loss.Comment: Accepted for publication in Astron. Astrophy

HI Observations of the Asymptotic Giant Branch Star X Herculis: Discovery of an Extended Circumstellar Wake Superposed on a Compact High-Velocity Cloud

We report HI 21-cm line observations of the AGB star X Her obtained with the Green Bank Telescope (GBT) and the Very Large Array (VLA). We have detected HI emission totaling M_HI=2.1e-03 M_sun associated with the circumstellar envelope of the star. The HI distribution exhibits a head-tail morphology, similar to those previously observed around Mira and RS Cnc. The tail extends ~6.0' (0.24 pc) in the plane of the sky, along the direction of the star's space motion. We also detect a velocity gradient of ~6.5 km/s across the envelope, consistent with the HI tracing a turbulent wake that arises from the motion of a mass-losing star through the ISM. GBT mapping of a 2x2deg region around X Her reveals that the star lies (in projection) near the periphery of a much larger HI cloud that also exhibits signatures of ISM interaction. The properties of the cloud are consistent with those of compact high-velocity clouds. Using CO observations, we have placed an upper limit on its molecular gas content of N_H2<1.3e20 cm^-2. Although the distance to the cloud is poorly constrained, the probability of a chance coincidence in position, velocity, and apparent position angle of space motion between X Her and the cloud is extremely small, suggesting a possible physical association. However, the large HI mass of the cloud (~>2.4~M_sun) and the blueshift of its mean velocity relative to X Her are inconsistent with an origin tied directly to stellar ejection. (abridged)Comment: Accepted to AJ; 47 pages, 15 figures; version with full resolution figures available at http://www.haystack.mit.edu/hay/staff/lmatthew/matthews_XHer.pd

Discrimination of three genetically close Aspergillus species by using high resolution melting analysis applied to indoor air as case study.

peer reviewedBACKGROUND: Indoor air pollution caused by fungal contamination is suspected to have a public health impact. Monitoring of the composition of the indoor airborne fungal contaminants is therefore important. To avoid problems linked to culture-dependent protocols, molecular methods are increasingly being proposed as an alternative. Among these molecular methods, the polymerase chain reaction (PCR) and the real-time PCR are the most frequently used tools for indoor fungal detection. However, even if these tools have demonstrated their appropriate performance, some of them are not able to discriminate between species which are genetically close. A solution to this could be the use of a post-qPCR high resolution melting (HRM) analysis, which would allow the discrimination of these species based on the highly accurate determination of the difference in melting temperature of the obtained amplicon. In this study, we provide a proof-of-concept for this approach, using a dye adapted version of our previously developed qPCR SYBR(R)Green method to detect Aspergillus versicolor in indoor air, an important airborne fungus in terms of occurrence and cause of health problems. Despite the good performance observed for that qPCR method, no discrimination could previously be made between A. versicolor, Aspergillus creber and Aspergillus sydowii. METHODS: In this study, we developed and evaluated an HRM assay for the discrimination between A. versicolor, Aspergillus creber and Aspergillus sydowii. RESULTS: Using HRM analysis, the discrimination of the 3 Aspergillus species could be made. No false positive, nor false negatives were observed during the performance assessment including 20 strains of Aspergillus. The limit of detection was determined for each species i.e., 0.5 pg of gDNA for A. creber and A. sydowii, and 0.1 pg of gDNA for A. versicolor. The HRM analysis was also successfully tested on environmental samples. CONCLUSION: We reported the development of HRM tools for the discrimination of A. versicolor, A. creber and A. sydowii. However, this study could be considered as a study case demonstrating that HRM based on existing qPCR assays, allows a more accurate identification of indoor air contaminants. This contributes to an improved insight in the diversity of indoor airborne fungi and hence, eventually in the causal link with health problems

Advantages of hydrogen addition in a passive pre-chamber ignited SI engine for passenger car applications

[EN] Hydrogen is one of the most promising alternative fuels for the transportation industry. The use of hydrogen to enable lean burn in internal combustion engines is an attractive solution for reducing CO2 emissions from two points of views: the substitution of carbon-based fuels and the increased thermal efficiency due to lean operation. Combining this strategy with the passive pre-chamber ignition system with gasoline/hydrogen blends is even more interesting. The main limitations of the passive pre-chamber concept in a high compression ratio spark-ignition engine were shown through engine experiments. A numerical study was then performed to evaluate the chance of extending the dilution limit by using hydrogen along with this technology. Results show how the use of hydrogen provides considerable benefits in the main chamber combustion process by enhancing the thermo-chemical properties of the mixture, increasing the flame speed, and improving the flame structure. Using an adequate gasoline-hydrogen blend proved to enable optimum burning rates at lean conditions, leading to a relevant thermal efficiency gain.Ministerio de Economia, Industria y Competitividad, Gobierno de Espana, Grant/Award Number: TRA2017-89139-C2-1-R; Universitat Politecnica de Valencia, Grant/Award Number: FPI-S1-2019-0033Benajes, J.; Novella Rosa, R.; Gómez-Soriano, J.; Barbery-Avila, II.; Libert, C. (2021). Advantages of hydrogen addition in a passive pre-chamber ignited SI engine for passenger car applications. International Journal of Energy Research. 45(9):13219-13237. https://doi.org/10.1002/er.6648132191323745

Dynamical stability analysis of the HD202206 system and constraints to the planetary orbits

Long-term precise Doppler measurements with the CORALIE spectrograph revealed the presence of two massive companions to the solar-type star HD202206. Although the three-body fit of the system is unstable, it was shown that a 5:1 mean motion resonance exists close to the best fit, where the system is stable. We present here an extensive dynamical study of the HD202206 system aiming at constraining the inclinations of the two known companions, from which we derive possible ranges of value for the companion masses. We study the long term stability of the system in a small neighborhood of the best fit using Laskar's frequency map analysis. We also introduce a numerical method based on frequency analysis to determine the center of libration mode inside a mean motion resonance. We find that acceptable coplanar configurations are limited to inclinations to the line of sight between 30 and 90 degrees. This limits the masses of both companions to roughly twice the minimum. Non coplanar configurations are possible for a wide range of mutual inclinations from 0 to 90 degrees, although $\Delta\Omega = 0 [\pi]$ configurations seem to be favored. We also confirm the 5:1 mean motion resonance to be most likely. In the coplanar edge-on case, we provide a very good stable solution in the resonance, whose $\chi^2$ does not differ significantly from the best fit. Using our method to determine the center of libration, we further refine this solution to obtain an orbit with a very low amplitude of libration, as we expect dissipative effects to have dampened the libration.Comment: 14 pages, 18 figure

effect of continuous heat exposure on sleep during partial sleep deprivation

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