The optical counterpart of the bright X-ray transient Swift J1745-26

We present a 30-day monitoring campaign of the optical counterpart of the bright X-ray transient Swift J1745-26, starting only 19 minutes after the discovery of the source. We observe the system peaking at i' ~17.6 on day 6 (MJD 56192) to then decay at a rate of ~0.04 mag/day. We show that the optical peak occurs at least 3 days later than the hard X-ray (15-50 keV) flux peak. Our measurements result in an outburst amplitude greater than 4.3 magnitudes, which favours an orbital period < 21 h and a companion star with a spectral type later than ~ A0. Spectroscopic observations taken with the GTC-10.4 m telescope reveal a broad (FWHM ~ 1100 km/s), double-peaked H_alpha emission line from which we constrain the radial velocity semi-amplitude of the donor to be K_2 > 250 km/s. The breadth of the line and the observed optical and X-ray fluxes suggest that Swift J1745-26 is a new black hole candidate located closer than ~7 kpc.Comment: 5 pages, 4 figures, accepted for publication in MNRA

Richness and Current Status of Gymnosperm Communities in Aguascalientes, Mexico

The gymnosperm diversity of Aguascalientes, Mexico, is presented. Fifteen species from five genera and three families are reported, two of Coniferales (Cupressaceae and Pinaceae) and one of Gnetales (Ephedraceae). Pinus is the most diverse and abundant genus with seven species. The most abundant species is P. teocote, while P. strobiformis is the scarcest. Juniperus is the next most diverse genus, represented by four species, with J. deppeana the most abundant and J. durangensis the scarcest. Cupressus lusitanica, Taxodium mucronatum and Ephedra compacta are each the sole representatives of their genera. Most conifers occupy the mountainous part of the state, forming temperate forest; exceptions are Taxodium, which is located on the margins of permanent streams, and J. coahuilensis, which is found in the low parts of the Aguascalientes Valley over calcareous soils in the northern part of the state. Ephedra is distributed in the northeast part of Aguascalientes in microphyll desert scrub. The current status of the gymnosperm communities in the state of Aguascalientes is discussed

Microbiota characterization in Blastocystis-colonized and Blastocystis-free school-age children from Colombia

Background Blastocystis is a protist that lives in the intestinal tract of a variety of hosts, including humans. It is still unclear how Blastocystis causes disease, which presents an ongoing challenge for researchers. Despite the controversial findings on the association between Blastocystis and clinical digestive manifestations, there is currently no consensus as to whether this protozoan actually behaves as a pathogen in humans. Furthermore, the relationship between Blastocystis and the intestinal microbiota composition is not yet clear. For that reason, the aim of this study was to identify if colonization by Blastocystis is related to changes in the diversity and relative abundance of bacterial communities, compared with those of Blastocystis-free individuals in a group of Colombian children. Methods We took stool samples from 57 school-aged children attending a daycare institution in Popayán (Southwest Colombia). Whole DNA was extracted and examined by 16S-rRNA amplicon-based sequencing. Blastocystis was detected by real time PCR and other intestinal parasites were detected by microscopy. We evaluated if Blastocystis was associated with host variables and the diversity and abundance of microbial communities. Results The composition of the intestinal bacterial community was not significantly different between Blastocystis-free and Blastocystis-colonized children. Despite this, we observed a higher microbial richness in the intestines of children colonized by Blastocystis, which could, therefore, be considered a benefit to intestinal health. The phylum Firmicutes was the predominant taxonomic unit in both groups analyzed. In Blastocystis-free individuals, there was a higher proportion of Bacteroidetes; similarly, in children colonized by Blastocystis, there was a higher relative abundance of the phylum Proteobacteria; however, no statistically significant differences were found between the comparison groups. Conclusions The presence of Blastocystis showed a decrease in Bacteroides, and an increase in the relative abundance of the genus Faecalibacterium. It was also evident that the presence of Blastocystis was unrelated to dysbiosis at the intestinal level; on the contrary, its presence did not show statistically differences in the intestinal microbiota composition. Nevertheless, we believe that Blastocystis plays a role in the ecology of the intestinal microbiota through its interaction with other microbial components

Life cycle assessment of households in Santiago, Chile: Environmental hotspots and policy analysis

Indexación ScopusThe aim of this study is to assess the environmental impacts of household life cycles in Santiago, Chile, by household income level. The assessment considered scenarios associated with environmental policies. The life cycle assessment was cradle-to-grave, and the functional unit considered all the materials and energy required to meet an inhabitant’s needs for one year (1 inh/year). Using SimaPro 9.1 software, the Recipe Midpoint (H) methodology was used. The impact categories selected were global warming, fine particulate matter formation, terrestrial acidification, freshwater eutrophication, freshwater ecotoxicity, mineral resource scarcity, and fossil resource scarcity. The inventory was carried out through the application of 300 household surveys and secondary information. The main environmental sources of households were determined to be food consumption, transport, and electricity. Food consumption is the main source, responsible for 33% of the environmental impacts on global warming, 69% on terrestrial acidification, and 29% on freshwater eutrophica-tion. The second most crucial environmental hotspot is private transport, whose contribution to environmental impact increases as household income rises, while public transport impact increases in the opposite direction. In this sense, both positive and negative environmental effects can be generated by policies. Therefore, life-cycle environmental impacts, the synergy between policies, and households’ socio-economic characteristics must be considered in public policy planning and consumer decisions. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.https://www.mdpi.com/2071-1050/13/5/252

A decade of GRB follow-up by BOOTES in Spain (2003-2013)

This article covers ten years of GRB follow-ups by the Spanish BOOTES stations: 71 follow-ups providing 23 detections. Follow-ups by BOOTES-1B from 2005 to 2008 were given in the previous article, and are here reviewed, updated, and include additional detection data points as the former article merely stated their existence. The all-sky cameras CASSANDRA have not yet detected any GRB optical afterglows, but limits are reported where available

Charged Higgs in 3-3-1 Model Through e−e+e^-e^+ Collisions

In this work we present an analysis of production and signature of charged Higgs bosons $H_2^{\pm}$ in the version of the 3-3-1 model containing heavy leptons at the CLIC (Cern Linear Collider). The production rate is found to be significant for the direct production of $e^{-} e^{+} \rightarrow H_{2}^{+} H_{2}^{-}$. We also studied the possibility to identify it using their respective branching ratios.Comment: 16 pages, 9 Figures. arXiv admin note: substantial text overlap with arXiv:1408.5944; text overlap with arXiv:1311.0845, arXiv:1205.404

Percepción de empleadores sobre las competencias de graduados del Programa de Enfermería de la Fundación Universitaria del Área Andina de Pereira (Colombia)

Objective The aim of this study is to identify the perceptions of employers on the competences from graduated students from the Nursing Program at Fundación Universitaria del Área Andina in Pereira (Colombia). These students were employed between 2006 and 2010. Methodology A descriptive study was conducted with a random sample with 95% confidence level and 5,0 % error which corresponded to 61 employers who voluntarily agreed to answer the survey from the labor observatory for education, to which was added the specific competencies of nursing. The level and importance of competence assigned by the employer were measured. We searched the mean difference in the two measurements to evaluate their correspondence. Results The levels of competence followed the same curve of importance of the competence with differences of less than 25,0%. Employers perceived high levels of performance in all competences analyzed. Conclusions It was made evident that there is correspondence between the required job profile and the development of general and specific competences for the training of nurses.Objetivo Identificar la percepción de empleadores sobre las competencias de graduados del Programa de Enfermería en la Fundación Universitaria del Área Andina de Pereira (Colombia), empleados entre los años 2006 a 2010. Metodología Estudio descriptivo en una muestra aleatoria con 95% de nivel de confianza y 5,0% de error que correspondió a 61 empleadores, quienes aceptaron voluntariamente contestar la encuesta del observatorio laboral para la educación, a la cual se agregaron las competencias específicas de enfermería. Se midieron: nivel de competencia observado e importancia de la competencia asignada por el empleador y se buscó la diferencia de medias en las dos mediciones para evaluar su correspondencia. Resultados Los niveles de competencia siguieron la misma curva de la importancia de la competencia, con diferencias inferiores al 25,0%. Los empleadores percibieron altos niveles de desempeño en todas las competencias analizadas. Conclusiones Se evidenció correspondencia entre el perfil laboral requerido y el desarrollo de competencias generales y específicas durante la formación de enfermeros

Comparative evaluation of R1234yf, R1234ze(E) and R450A as alternatives to R134a in a variable speed reciprocating compressor

A comparative energetic evaluation of R1234yf, R1234ze(E) and R450A as alternatives to R134a in a variable speed compressor is carried out. A compressor model based on dimensionless numbers was obtained using the Buckingham p -theorem, which was validated with experimental data; showing that the prediction error of the model is lower than ± 10% and ± 2 K for temperature. The experimental data were obtained by testing R134a, R1234yf, R1234ze(E) and R450A for a wide range of operating condi- tions. Results obtained with the validated model, show that the dimensionless approach provides a similar estimation of energy parameters compared with the experimental results, such as power con- sumption, refrigerant mass fl ow rate, cooling capacity, COP, discharge temperature and compressor ef- fi ciencies for each refrigerant tested using the dimensionless approach proposed. The comparative evaluation of the compressor predictions shows a reduction in the cooling capacity obtained with R1234yf, R450A and R1234ze(E), in comparison with R134a. Also, COP values for R1234yf, R450A, and R1234ze(E) are lower than those obtained from R134a. Finally, results shows that the dimensionless correlation compressor model can be used to predict the performance of other reciprocating compres- sors, at similar operating conditions for a wide range of compressor rotation speed, with a reasonable accuracy.The authors thankfully acknowledge to the "Consejo Nacional deCiencia y Tecnología (CONACYT)” for their support to this study, and to the “Ministerio de Educación, Cultura y Deporte” (Grant number FPU12/02841) for sponsoring this work through “Becas y Contratosde Formación de Profesorado Universitario del Programa Nacional de Formación de Recursos Humanos de Investigación del ejercicio 2012”

Prevalence, risk factors, and identification of Salmonella spp. in stray dogs of northwest Mexico

Salmonellosis has a worldwide relevance in aspects associated with public health, as only in 2009 were reported 93.8 million cases in humans. The objective of the study was to establish the prevalence, risk factors and bacteriological and molecular identification of Salmonella spp in stray dogs in urban, rural and coastal areas of Mexicali, a city in northwest Mexico. From May 2014 to February 2015, 385 dogs were tested. Sampling was performed by rectal swab and conventional bacteriological techniques were applied, for later implementation of the API 20E system and molecular identification by polymerase chain reaction (PCR). The data were analysed statistically by means of descriptive statistics and multiple logistic regression modelling. A prevalence of 6.27% was obtained in the dogs examined, the samples obtained were characterised to subspecies (Salmonella enterica subspecies enterica and Salmonella enterica subspecie arizonae). The geographical region with the highest prevalence in the study was the coast (10%), followed by the rural area (8.57%) and the urban area (5.8%), however, no significant statistical differences were detected. There was significant difference in the prevalence by age of dogs under one year (P&lt;0.05). The identification of Salmonella in dogs from northwest Mexico could correspond to serovars of zoonotic importance indicating a potential risk for the population

Efecto antiinflamatorio de la izalpinina derivada de Chromolaena leivensis: edema de la pata inducido por λ-carragenina y modelo in silico

El flavonoide izalpinina se aisló de las partes aéreas de Chromolaena leivensis. Su determinación estructural se llevó a cabo mediante técnicas espectroscópicas de EM y RMN (1H, 13C). Se evaluó el efecto antiinflamatorio de este compuesto en un modelo de edema plantar inducido por carragenina en ratas. La inflamación de la pata se midió a intervalos de una hora durante siete horas tras la administración de -carragenano. Se evaluaron los niveles séricos de creatina quinasa (CK), obteniéndose resultados estadísticamente significativos con los tratamientos a dosis de 10 mg/kg (* p < 0,01) y 20 mg/kg (** p < 0,005). El efecto antiinflamatorio del compuesto se evaluó mediante pletismografía, y los resultados mostraron diferencias significativas en las tres concentraciones (10 mg/kg, 20 mg/kg, 40 mg/kg) en la primera y tercera hora tras el tratamiento. * p < 0,05; ** p < 0,001; **** p < 0,0001 frente al grupo de control negativo tratado con vehículo (DMSO). Por último, los análisis de acoplamiento molecular revelan que la izalpinina tiene una fuerte afinidad de unión con cinco proteínas diana implicadas en el proceso inflamatorio. El análisis mediante dinámica molecular permitió demostrar que los complejos ligando-proteína presentan una estabilidad aceptable, con valores de RMSD dentro del rango permitido.The flavonoid izalpinin was isolated from the aerial parts of Chromolaena leivensis. Its structural determination was carried out using MS and NMR spectroscopic techniques (1H, 13C). This compound was evaluated for its anti-inflammatory effect in a rat model on -carrageenan-induced plantar edema. Paw inflammation was measured at one-hour intervals for seven hours following the administration of -carrageenan. Serum creatine kinase (CK) levels were evaluated, obtaining statistically significant results with the treatments at doses of 10 mg/kg (* p < 0.01) and 20 mg/kg (** p < 0.005). The anti-inflammatory effect of the compound was evaluated by using plethysmography, and the results showed significant differences at the three concentrations (10 mg/kg, 20 mg/kg, 40 mg/kg) in the first and third hours after treatment. * p < 0.05; ** p < 0.001; **** p < 0.0001 vs. the negative control group treated with vehicle (DMSO). Lastly, molecular docking analyses reveal that izalpinin has a strong binding affinity with five target proteins involved in the inflammatory process. The analysis using molecular dynamics allowed demonstrating that the ligand–protein complexes present acceptable stability, with RMSD values within the allowed range