Broadening of H2_2O rotational lines by collision with He atoms at low temperature

We report pressure broadening coefficients for the 21 electric-dipole transitions between the eight lowest rotational levels of ortho-H$_2$O and para-H$_2$O molecules by collisions with He at temperatures from 20 to 120 K. These coefficients are derived from recently published experimental state-to-state rate coefficients for H$_2$O:He inelastic collisions, plus an elastic contribution from close coupling calculations. The resulting coefficients are compared to the available experimental data. Mostly due to the elastic contribution, the pressure broadening coefficients differ much from line to line, and increase markedly at low temperature. The present results are meant as a guide for future experiments and astrophysical observations.Comment: 2 figures, 2 table

A Spectroscopic Study of the Near-IR [SIII] Lines in a Sample of HII Galaxies: chemical abundances

A detailed spectroscopic study, from lambda 3700 A to 1 um, was performed for a sample of 34 HII galaxies in order to derive fundamental parameters for their HII regions and ionizing sources, as well as gaseous metal abundances. All the spectra included the nebular [SIII]9069,9532 A lines, given their importance in the derivation of the S/H abundance and relevant ionization diagnostics. A systematic method was followed to correct the near-IR [SIII] line fluxes for the effects of the atmospheric transmission.A comparative analysis of the predictions of the empirical abundance indicators R23 and S23 has been performed. The relative hardness of their ionizing sources was studied using the eta parameter, and exploring the role played by metallicity. For 22 galaxies of the sample a direct value of te[SIII] was derived, along with their ionic and total S/H abundances. Their ionic and total O/H abundances were derived using direct determinations of te[OIII].For the rest of the objects, the total S/H abundance was derived using S23. The abundance range covered by our sample goes from 1/20 solar up to solar metallicity. The mean S/O ratio derived is log (S/O)=-1.68+/-0.20 dex, 1 sigma below the solar S/O value. The S/O abundance ratio shows no significant trend with O/H over the range of abundance covered in this work, in agreement with previous findings.There is a trend for HII galaxies with lower gaseous metallicity to present harder ionizing spectra. We compared the distribution of the ionic ratios O+/O++ vs. S+/S++ derived for our sample with the predictions of a grid of photoionization models performed for different stellar effective temperatures. This analysis indicates that a large fraction of galaxies in our sample seem to be ionized by extremely hard spectra.Comment: 12 pages, 8 figures, accepted for publication in the A&A, minor gramatical corrections include

Epidemiologic and Clinical Impact of Acinetobacter baumannii Colonization and Infection: A Reappraisal

Acinetobacter baumannii is one of the most important antibiotic-resistant nosocomial bacteria. We investigated changes in the clinical and molecular epidemiology of A. baumannii over a 10-year period. We compared the data from 2 prospective multicenter cohort studies in Spain, one performed in 2000 (183 patients) and one in 2010 (246 patients), which included consecutive patients infected or colonized by A. baumannii. Molecular typing was performed by repetitive extragenic palindromic polymerase chain reaction (REP-PCR), pulsed-field gel electrophoresis (PFGE), and multilocus sequence typing (MLST). The incidence density of A. baumannii colonization or infection increased significantly from 0.14 in 2000 to 0.52 in 2010 in medical services (p<0.001). The number of non-nosocomial health careassociated cases increased from 1.2% to 14.2%, respectively (p<0.001). Previous exposure to carbapenems increased in 2010 (16.9% in 2000 vs 27.3% in 2010, p¼0.03). The drugs most frequently used for definitive treatment of patients with infections were carbapenems in 2000 (45%) and colistin in 2010 (50.3%). There was molecular-typing evidence of an increase in the frequency of A. baumannii acquisition in non-intensive care unit wards in 2010 (7.6% in 2000 vs 19.2% in 2010, p¼0.01). By MSLT, the ST2 clonal group predominated and increased in 2010. This epidemic clonal group was more frequently resistant to imipenem and was associated with an increased risk of sepsis, although not with severe sepsis or mortality. Some significant changes were noted in the epidemiology of A. baumannii, which is increasingly affecting patients admitted to conventional wards and is also the cause of non-nosocomial health care-associated infections. Epidemic clones seem to combine antimicrobial resistance and the ability to spread, while maintaining their clinical virulence.Ministerio de Ciencia e InnovaciónInstituto de Salud Carlos IIIEuropean Development Regional Fund “A way to achieve Europe” ERDFSpanish Network for the Research in Infectious Diseases REIPI RD06/0008FIS PI 10/00056 and PI 11/0204

Characterization of source rocks and groundwater radioactivity at the Chihuahua valley

As part of a scientific research project about alpha radioactivity in groundwater for human consumption at the Chihuahua City, the charac-terization of rock sources of radioactivity around de Chihuahua valley was developed. The radioactivity of groundwater and sediments wasdetermined, too. The radioactivity of uranium- and thorium- series isotopes contained in rocks was obtained by high resolution gamma-rayspectroscopy. Some representative values are 50 Bq/kg for the mean value of Bi-214 activity, and 121.5 Bq/kg for the highest value at Westof the city. The activity of sediments, extracted during wells perforation, was determined using a NaI(Tl) detector. A non-reported beforeuranium ore was localized at the San Marcos range formation. Its outcrops are inside the Chihuahua-Sacramento valley basin and its activ-ity characterization was performed. Unusually high specific uranium activities, determined by alpha spectrometry, were obtained in water,plants, sediments and fish extracted at locations close to outcrops of uranium minerals. The activity of water of the San Marcos dam reached7.7 Bq/L. The activity of fish, trapped at San Marcos dam, is 0.99 Bq/kg. Conclusions about the contamination of groundwater at North ofChihuahua City were obtained.Como parte de un proyecto cient ́ıfico sobre actividad alfa en agua subterr ́anea de consumo humano en la ciudad de Chihuahua, se hadesarrollado la caracterizaci ́on de las rocas fuentes de la radiactividad en el valle de Chihuahua. Se determin ́o tambi ́en la actividad de muestrasde agua subterr ́anea y de sedimentos. La actividad de los is ́otopos de las series radiactivas en las rocas se obtuvo usando espectroscop ́ıagamma de alta resoluci ́on. Algunos valores representativos son 50 Bq/kg para el valor medio de la actividad del Bi-214 y 121.5 Bq/kg para elvalor m ́as alto al oeste de la ciudad. La actividad de los sedimentos extra ́ıdos durante la perforaci ́on de pozos para agua potable, se determin ́ousando un detector de NaI(Tl). En la formaci ́on monta ̃nosa de San Marcos se localiz ́o un dep ́osito de uranio no publicado. Sus afloramientosse encuentran dentro de la cuenca del valle Chihuahua-Sacramento y se realiz ́o la caracterizaci ́on de su radiactividad. Se determinaronactividades por espectrometr ́ıa alfa de agua, plantas, sedimentos y peces extra ́ıdos en emplazamientos cercanos a los afloramientos deminerales de uranio. La actividad del agua en la presa de san Marcos lleg ́o a 7.7 Bq/L. La actividad de pescados de la misma presa alcanza0.99 Bq/kg. Se obtuvieron conclusiones sobre la contaminaci ́on del agua subterr ́anea al norte de la ciudad de Chihuahua

Influence of seed layer thickness on properties of electrodeposited ZnO nanostructured films

The quality and properties of electrodeposited nanostructured ZnO films are improved when they are deposited on a crystal lattice-matching substrate. To this end, a highly conductive indium tin oxide substrate is covered with an interlayer of ZnO using direct-current magnetron sputtering. In this manuscript, we describe the effect of this interlayer on the morphological and optical properties of several nanostructured ZnO films grown by different electrodeposition methods. The thickness of the ZnO interlayer was varied starting from ultrathin layers of 10 nm all the way up to 230 nm as determined by ellipsometry. The structural and optical properties of the nanostructured ZnO films deposited on top of these interlayers were characterized using field emission scanning electron microscopy (FESEM), atomic force microscopy and UV–visible spectroscopy. Optimum properties of the nanostructured ZnO films for application in thin-film optoelectronic devices are obtained when the ZnO interlayer has a thickness of approximately 45 nm. This is the case for all the electrodeposition methods used in this work.Facultad de Ciencias ExactasInstituto de Física La Plat

Physical and chemical properties of soils irrigated with vinasses for the cultivation of sugarcane (Saccharum spp.) in the central region of Veracruz, Mexico

Objective: To evaluate the physical and chemical properties of a soil with vinasse application (two years) (V), compared to a soil without vinasse (W/V). Design/methodology/approach: In both agroecosystems, the evaluated parameters were texture, pH, electrical conductivity (EC), organic matter (OM), phosphorus (P), potassium (K), nitrates (NO3) and total nitrogen (TN) according to standardized methods in NOM-021-SEMARNAT-2000. Results: There were no significant changes (p&gt;0.05) in the pH and electrical conductivity, however, the application of vinasse significantly increased (p˂0.05) the content of TN (1.52%), K (112.00 mg L-1) and OM (4.52%) in relation to soils W/V (0.78%, 25.60 mg L-1, 7.40 mg L-1, 2.75%, respectively). Limitations on study/implications: In Veracruz state, there are few studies that allow knowing the contributions, and physical and chemical effects on soils irrigated with vinasses. Findings/conclusions: Even though, the vinasse used showed a positive effect on the physical and chemical characteristics of the soil (V), the mineral fertilization program must be reformulated to increase the concentration of potassium and phosphorus in soils with silt loam texture. In addition, it is recommended to adjust and normalize the dose of N that vinasse can provide instead of conventional fertilizers. Keywords: Soil fertility, sugarcane, vinasses.Objective: To evaluate the physical and chemical properties of a soil irrigated with vinasse for two years (+V), compared with a soil without vinasse (-V) application.Design/Methodology/Approach: The following parameters were evaluated for both agroecosystems: texture, pH, electrical conductivity (EC), organic matter (OM), phosphorus (P), potassium (K), nitrate (NO 3 ), and total nitrogen (TN). The evaluation followed the standardized methods established in NOM-021-SEMARNAT-2000.Results: There were no significant changes (p &amp;gt; 0.05) in the soil’s pH and electrical conductivity. However, the application of vinasse significantly increased (p &amp;lt; 0.05) the concentrations of TN (1.52%), K (112.00 mg L -1 ), and OM (4.52%) in relation to soils - V (0.78%, 25.60 mg L -1 , 7.40 mg L-1 , and 2.75%, respectively). Study Limitations/Implications: There are few studies about the contributions and the physical and chemical effects of soil irrigation with vinasses in the State of Veracruz.Findings/Conclusions: Even though vinasse had a positive effect on the physical and chemical characteristics of the soil, the mineral fertilization program must be reformulated to increase the K and P concentration in soils with silt loam texture. In addition, we recommend adjusting and normalizing the dose of N that vinasse can provide to complement conventional fertilizers

Spatio-temporal tumor heterogeneity in metastatic CRC tumors: a mutational-based approach

[EN] It is well known that activating mutations in the KRAS and NRAS genes are associated with poor response to anti-EGFR therapies in patients with metastatic colorectal cancer (mCRC). Approximately half of the patients with wild-type (WT) KRAS colorectal carcinoma do not respond to these therapies. This could be because the treatment decision is determined by the mutational profile of the primary tumor, regardless of the presence of small tumor subclones harboring RAS mutations in lymph nodes or liver metastases. We analyzed the mutational profile of the KRAS, NRAS, BRAF and PI3KCA genes using low-density microarray technology in samples of 26 paired primary tumors, 16 lymph nodes and 34 liver metastases from 26 untreated mCRC patients (n=76 samples). The most frequent mutations found in primary tumors were KRAS (15%) and PI3KCA (15%), followed by NRAS (8%) and BRAF (4%). The distribution of the mutations in the 16 lymph node metastases analyzed was as follows: 4 (25%) in KRAS gene, 3 (19%) in NRAS gene and 1 mutation each in PI3KCA and BRAF genes (6%). As expected, the most prevalent mutation in liver metastasis was in the KRAS gene (35%), followed by PI3KCA (9%) and BRAF (6%). Of the 26 cases studied, 15 (58%) displayed an overall concordance in the mutation status detected in the lymph node metastases and liver metastases compared with primary tumor, suggesting no clonal evolution. In contrast, the mutation profiles differed in the primary tumor and lymph node/metastases samples of the remaining 11 patients (48%), suggesting a spatial and temporal clonal evolution. We confirm the presence of different mutational profiles among primary tumors, lymph node metastases and liver metastases. Our results suggest the need to perform mutational analysis in all available tumor samples of patients before deciding to commence anti-EGFR treatment