On the abundance discrepancy problem in HII regions

The origin of the abundance discrepancy is one of the key problems in the physics of photoionized nebula. In this work, we analize and discuss data for a sample of Galactic and extragalactic HII regions where this abundance discrepancy has been determined. We find that the abundance discrepancy factor (ADF) is fairly constant and of the order of 2 in all the available sample of HII regions. This is a rather different behaviour than that observed in planetary nebulae, where the ADF shows a much wider range of values. We do not find correlations between the ADF and the O/H, O++/H+ ratios, the ionization degree, Te(High), Te(Low)/ Te(High), FWHM, and the effective temperature of the main ionizing stars within the observational uncertainties. These results indicate that whatever mechanism is producing the abundance discrepancy in HII regions it does not substantially depend on those nebular parameters. On the contrary, the ADF seems to be slightly dependent on the excitation energy, a fact that is consistent with the predictions of the classical temperature fluctuations paradigm. Finally, we obtain that Te values obtained from OII recombination lines in HII regions are in agreement with those obtained from collisionally excited line ratios, a behaviour that is again different from that observed in planetary nebulae. These similar temperature determinations are in contradiction with the predictions of the model based on the presence of chemically inhomogeneous clumps but are consistent with the temperature fluctuations paradigm. We conclude that all the indications suggest that the physical mechanism responsible of the abundance discrepancy in HII regions and planetary nebulae are different.Comment: 14 pages, 8 figures, 9 tables. Accepted for publication in the Ap

Gnathostomosis, an emerging foodborne zoonotic disease in Acapulco, Mexico.

Between 1993 and 1997, 98 gnathostomosis cases were clinically identified in Acapulco, Mexico. Intermittent cutaneous migratory swellings were the commonest manifestation. Larvae were identified in 26 cases, while in 72, final diagnosis was made on the basis of epidemiologic data, food habits, and positive enzyme-linked immunosorbent assay and Western blot results

Pediatric traumatic brain injuries in war zones: a systematic literature review

BackgroundPediatric casualties in war zones are a devastating consequence of armed conflicts, causing significant challenges for affected children, especially in the context of poor access to care. This study aimed to understand traumatic brain injuries (TBIs) in this high-risk population and to identify and provide information for the stakeholders, as well as to recognize severe long-term consequences and develop strategies to prevent them, thus minimizing their burden while aiding in the management of these cases.MethodsWe carried out a systematic literature review following PRISMA guidelines to identify publications discussing traumatic brain injuries in children in the context of war zones, and we analyzed all the collected data.ResultsOur study showed that head injuries were the most common casualty in war zones; male and female children were affected, and the mean age was 8–10 years. Most children were reported to be from Afghanistan, and blasts were the most common mechanism of injury. The mortality fluctuated from 3 to 47%.ConclusionThere is a lack of evidence-based information regarding the characterization, approach, and management of children with TBI in conflict zones. While the world finds ways to live in peace, there is an urgency to research, train, and deploy enough specialists to these areas, if governments are serious about improving outcomes for this population

Tailoring the Properties of Thermo-Compressed Polylactide Films for Food Packaging Applications by Individual and Combined Additions of Lactic Acid Oligomer and Halloysite Nanotubes

[EN] In this work, films of polylactide (PLA) prepared by extrusion and thermo-compression were plasticized with oligomer of lactic acid (OLA) at contents of 5, 10, and 20 wt%. The PLA sample containing 20 wt% of OLA was also reinforced with 3, 6, and 9 parts per hundred resin (phr) of halloysite nanotubes (HNTs) to increase the mechanical strength and thermal stability of the films. Prior to melt mixing, ultrasound-assisted dispersion of the nanoclays in OLA was carried out at 100 ºC to promote the HNTs dispersion in PLA and the resultant films were characterized with the aim to ascertain their potential in food packaging. It was observed that either the individual addition of OLA or combined with 3 phr of HNTs did not significantly affect the optical properties of the PLA films, whereas higher nanoclay contents reduced lightness and induced certain green and blue tonalities. The addition of 20 wt% of OLA increased ductility of the PLA film by nearly 75% and also decreased the glass transition temperature (Tg) by over 18 ºC. The incorporation of 3 phr of HNTs into the OLA-containing PLA films delayed thermal degradation by 7 ºC and additionally reduced the permeabilities to water and limonene vapors by approximately 8% and 47%, respectively. Interestingly, the highest barrier performance was attained for the unfilled PLA film plasticized with 10 wt% of OLA, which was attributed to a crystallinity increase and an effect of ¿antiplasticization¿. However, loadings of 6 and 9 phr of HNTs resulted in the formation of small aggregates that impaired the performance of the blend films. The here-attained results demonstrates that the properties of ternary systems of PLA/OLA/HNTs can be tuned when the plasticizer and nanofiller contents are carefully chosen and the resultant nanocomposite films can be proposed as a bio-sourced alternative for compostable packaging applications.This research work was funded by the Spanish Ministry of Science and Innovation (MICI) project numbers RTI2018-097249-B-C21 and MAT2017-84909-C2-2-R. S.R.-L is a recipient of a Santiago Grisolia grant from Generalitat Valenciana (GVA) (GRISOLIAP/2019/132). L.Q.-C. wants to thank GVA for his FPI grant (ACIF/2016/182) and the Spanish Ministry of Education, Culture, and Sports (MECD) for his FPU grant (FPU15/03812), while D.G.-G. also acknowledges GVA for his postdoctoral contract (APOSTD/2019/201). B.M.-R. and S.T.-G. acknowledge MICIU for her FPI grant (BES-2016-077972) and his Juan de la Cierva¿Incorporación contract (IJCI-2016-29675), respectively.Rojas-Lema, S.; Quiles-Carrillo, L.; Garcia-Garcia, D.; Melendez-Rodriguez, B.; Balart, R.; Torres-Giner, S. (2020). Tailoring the Properties of Thermo-Compressed Polylactide Films for Food Packaging Applications by Individual and Combined Additions of Lactic Acid Oligomer and Halloysite Nanotubes. Molecules. 25(8). https://doi.org/10.3390/molecules2508197625

Unveiling the nature of IGR J17177-3656 with X-ray, NIR and Radio observations

We report on the first broad-band (1-200 keV) simultaneous Chandra-INTEGRAL observations of the recently discovered hard X-ray transient IGR J17177-3656 that took place on 2011, March 22, about two weeks after the source discovery. The source had an average absorbed 1-200 keV flux of about 8x10^(-10) erg cm^(-2) s^(-1). We extracted a precise X-ray position of IGR J17177-3656, RA=17 17 42.62, DEC= -36 56 04.5 (90% uncertainty of 0.6"). We also report Swift, near infrared and quasi simultaneous radio follow-up observations. With the multi-wavelength information at hand, we propose IGR J17177-3656 is a low-mass X-ray binary, seen at high inclination, probably hosting a black hole.Comment: 8 pages, 8 figures, accepted for publication in Ap

"HIV therapy adherence and outcomes in Peruvian military personnel over a 30-year period"

"Objectives: We aimed to describe the sociodemographic, clinical, and therapeutic characteristics of Peruvian military personnel diagnosed with HIV. Furthermore, we determined the frequency of highly active antiretroviral therapy (HAART) adherence, the complications and mortality. Methods: We retrospectively reviewed the medical records of patients diagnosed with HIV, confirmed by Western blot at a single institution from 1989-2020. Descriptive analyses were performed for all the variables using mean and standard deviation (SD) in the case of quantitative variables, and frequency and percentage for qualitative variables. Results:Ofthe 161 patients included, 95.7% were males and the mean age was 39.59 years (SD= 16.45 years). Most had college or higher education (67.7%) and were on active duty at diagnosis (77%). 35.4% had AIDS at diagnosis; 28.6% opportunistic infections; and 8.1% tuberculosis. The median follow-up was five years. 94.4% of the patients received HAART as the principal treatment; of these, 88.8% was adherent to treatment, and death was reported in 6.8%. There were no factors associated with adherence. Conclusions: Although the sociodemographic characteristics of Peruvian military personnel are similar to those of other countries, our findings suggest that Peruvian military personnel present higher adherence to HAART compared to previous studies in other military populations from South American countries. Further studies are recommended to assess specific factors attributed to these successful outcomes in the military personnelthat can be applied in other hospitals.

In vitro and in vivo leishmanicidal studies of Peperomia galioides (Piperaceae)

Petroleum ether and methylene chloride extracts of #Peperomia galioides and three phenylated diphenols, grifolic acid, grifolin and piperogalin exhibited in vitro antileishmanial activity. During the course of infection of BALB/c mice with #Leishmania amazonensis, the treatments with each of these compounds did not influence the progression of the disease. (Résumé d'auteur

Characterizing the Cool KOIs II. The M Dwarf KOI-254 and its Hot Jupiter

We report the confirmation and characterization of a transiting gas giant planet orbiting the M dwarf KOI-254 every 2.455239 days, which was originally discovered by the Kepler mission. We use radial velocity measurements, adaptive optics imaging and near infrared spectroscopy to confirm the planetary nature of the transit events. KOI-254b is the first hot Jupiter discovered around an M-type dwarf star. We also present a new model-independent method of using broadband photometry to estimate the mass and metallicity of an M dwarf without relying on a direct distance measurement. Included in this methodology is a new photometric metallicity calibration based on J-K colors. We use this technique to measure the physical properties of KOI-254 and its planet. We measure a planet mass of Mp = 0.505 Mjup, radius Rp = 0.96 Rjup and semimajor axis a = 0.03 AU, based on our measured stellar mass Mstar = 0.59 Msun and radius Rstar = 0.55 Rsun. We also find that the host star is metal-rich, which is consistent with the sample of M-type stars known to harbor giant planets.Comment: AJ accepted (in press

Sustainable sugarcane vinasse biorefinement for trans-aconitic acid-based biopolymer synthesis and bioenergy generation

This study aimed at developing a multiproduct biorefinery scheme for vinase valorization. It involved the extraction of trans-aconitic acid, its transformation into biopolymers using microwave irradiation and the use of the raffinated-vinasse for biogas production. Each technology was assessed individually, followed by a process integration at bench scale, from which a mass balance was calculated, supporting the feasibility of the approach. As a renewable source derived from a residue, these bioproducts can replace crude-oil-based materials in various chemical industrial processes; however, a detailed techno-economic and life-cycle analysis are required to defined the sustainability of the process