3,038 research outputs found
Assessing the influence of the carbon oxidation-reduction state on organic pollutant biodegradation in algal-bacterial photobioreactors
The influence of the carbon oxidation-reduction state (CORS) of organic pollutants on their biodegradation in enclosed algal-bacterial photobioreactors was evaluated using a consortium of enriched wild-type methanotrophic bacteria and microalgae. Methane, methanol and glucose (with CORS -4, -2 and 0, respectively) were chosen as model organic pollutants. In the absence of external oxygen supply, microalgal photosynthesis was not capable of supporting a significant methane and methanol biodegradation due to their high oxygen demands per carbon unit, while glucose was fully oxidized by photosynthetic oxygenation. When bicarbonate was added, removal efficiencies of 37¿±¿4% (20 days), 65¿±¿4% (11 days) and 100% (2 days) were recorded for CH(4,) CH(3)OH and C(6)H(12)O(6), respectively due to the additional oxygen generated from photosynthetic bicarbonate assimilation. The use of NO(3)(-) instead of NH(4)(+) as nitrogen source (N oxidation-reduction state of +5 vs. -3) resulted in an increase in CH(4) degradation from 0 to 33¿±¿3% in the absence of bicarbonate and from 37¿±¿4% to 100% in the presence of bicarbonate, likely due to a decrease in the stoichiometric oxygen requirements and the higher photosynthetic oxygen production. Hypothetically, the CORS of the substrates might affect the CORS of the microalgal biomass composition (higher lipid content). However, the total lipid content of the algal-bacterial biomass was 19¿±¿7% in the absence and 16¿±¿2% in the presence of bicarbonat
Current challenges in chronic bronchial infection in patients with chronic obstructive pulmonary disease
Currently, chronic obstructive pulmonary disease (COPD) patients and their physicians face a number of significant clinical challenges, one of which is the high degree of uncertainty related to chronic bronchial infection (CBI). By reviewing the current literature, several challenges can be identified, which should be considered as goals for research. One of these is to establish the bases for identifying the biological and clinical implications of the presence of potentially pathogenic microorganisms in the airways that should be more clearly elucidated according to the COPD phenotype. Another urgent area of research is the role of long-term preventive antibiotics. Clinical trials need to be carried out with inhaled antibiotic therapy to help clarify the profile of those antibiotics. The role of inhaled corticosteroids in patients with COPD and CBI needs to be studied to instruct the clinical management of these patients. Finally, it should be explored and confirmed whether a suitable antimicrobial treatment during exacerbations may contribute to breaking the vicious circle of CBI in COPD. The present review addresses the current state of the art in these areas to provide evidence which will enable us to progressively plan better healthcare for these patients
Ages and Metallicities of Hickson Compact Group Galaxies
Hickson Compact Groups (HCGs) constitute an interesting extreme in the range
of environments in which galaxies are located, as the space density of galaxies
in these small groups are otherwise only found in the centres of much larger
clusters. The work presented here uses Lick indices to make a comparison of
ages and chemical compositions of galaxies in HCGs with those in other
environments (clusters, loose groups and the field). The metallicity and
relative abundance of `-elements' show strong correlations with galaxy
age and central velocity dispersion, with similar trends found in all
environments. However, we show that the previously reported correlation between
-element abundance ratios and velocity dispersion disappears when a
full account is taken of the the abundance ratio pattern in the calibration
stars. This correlation is thus found to be an artifact of incomplete
calibration to the Lick system.
Variations are seen in the ranges and average values of age, metallicity and
-element abundance ratios for galaxies in different environments. Age
distributions support the hierarchical formation prediction that field galaxies
are on average younger than their cluster counterparts. However, the ages of
HCG galaxies are shown to be more similar to those of cluster galaxies than
those in the field, contrary to the expectations of current hierarchical
models. A trend for lower velocity dispersion galaxies to be younger was also
seen. This is again inconsistent with hierarchical collapse models, but is
qualitatively consistent with the latest N-body-SPH models based on monolithic
collapse in which star formation continues for many Gyr in low mass halos.Comment: 18 pages. Submitted for publication in MNRA
The role of PKD1 in aging-related neurodegeneration: Structural and functional imaging studies
Trabajo presentado en el Second Spanish Molecular Imaging Network (SMIN) Meeting, celebrado en Madrid (España) el 26 de febrero de 2018
Predicting high risk of exacerbations in bronchiectasis: the E-FACED score
BACKGROUND: Although the FACED score has demonstrated a great prognostic capacity in bronchiectasis, it does not include the number or severity of exacerbations as a separate variable, which is important in the natural history of these patients. OBJECTIVE: Construction and external validation of a new index, the E-FACED, to evaluate the predictive capacity of exacerbations and mortality. METHODS: The new score was constructed on the basis of the complete cohort for the construction of the original FACED score, while the external validation was undertaken with six cohorts from three countries (Brazil, Argentina, and Chile). The main outcome was the number of annual exacerbations/hospitalizations, with all-cause and respiratory-related deaths as the secondary outcomes. A statistical evaluation comprised the relative weight and ideal cut-off point for the number or severity of the exacerbations and was incorporated into the FACED score (E-FACED). The results obtained after the application of FACED and E-FACED were compared in both the cohorts. RESULTS: A total of 1,470 patients with bronchiectasis (819 from the construction cohorts and 651 from the external validation cohorts) were followed up for 5 years after diagnosis. The best cut-off point was at least two exacerbations in the previous year (two additional points), meaning that the E-FACED has nine points of growing severity. E-FACED presented an excellent prognostic capacity for exacerbations (areas under the receiver operating characteristic curve: 0.82 for at least two exacerbations in 1 year and 0.87 for at least one hospitalization in 1 year) that was statistically better than that of the FACED score (0.72 and 0.78, P<0.05, respectively). The predictive capacities for all-cause and respiratory mortality were 0.87 and 0.86, respectively, with both being similar to those of the FACED. CONCLUSION: E-FACED score significantly increases the FACED capacity to predict future yearly exacerbations while maintaining the score’s simplicity and prognostic capacity for death
Safety of switching from intravenous to subcutaneous rituximab during first-line treatment of patients with non-Hodgkin lymphoma: the Spanish population of the MabRella study
Rituximab is a standard treatment for non-Hodgkin diffuse large B-cell
(DLBCL) and follicular (FL) lymphomas. A subcutaneous formulation was
developed to improve the resource use of intravenous rituximab, with comparable efficacy and safety profiles except for increased administration-related reactions (ARRs). MabRella was a phase IIIb trial to assess the safety
of switching from intravenous to subcutaneous administration of rituximab
during first-line induction/maintenance for DLBCL or FL, focusing on
ARRs. Efficacy, satisfaction and quality of life were also assessed. Patients
received subcutaneous rituximab plus standard induction chemotherapy for
DLBCL or FL for 4–7 cycles, and/or every 2 months maintenance
monotherapy for FL for 6–12 cycles. The study included 140 patients:
DLBCL, n = 29; FL, n = 111. Ninety-five percent of patients experienced
adverse events, reaching grade ≥3 in 38 6% and were serious in 30 0%.
AARs occurred in 48 6%, mostly (84 9%) at the injection site, with only
2 1% of patients reaching grade 3. The end-of-induction complete/unconfirmed complete response rate was 69 6%. After a median follow-up of
33 5 months, median disease-/event-/progression-free and overall survivals
were not attained. The Rituximab Administration Satisfaction Questionnaire showed improvements in overall satisfaction and the EuroQoL-5D a
good quality-of-life perception at induction/maintenance end. Therefore,
switching to subcutaneous rituximab showed no new safety issues and
maintained efficacy with improved satisfaction and quality of life
The 2HWC HAWC Observatory Gamma Ray Catalog
We present the first catalog of TeV gamma-ray sources realized with the
recently completed High Altitude Water Cherenkov Observatory (HAWC). It is the
most sensitive wide field-of-view TeV telescope currently in operation, with a
1-year survey sensitivity of ~5-10% of the flux of the Crab Nebula. With an
instantaneous field of view >1.5 sr and >90% duty cycle, it continuously
surveys and monitors the sky for gamma ray energies between hundreds GeV and
tens of TeV.
HAWC is located in Mexico at a latitude of 19 degree North and was completed
in March 2015. Here, we present the 2HWC catalog, which is the result of the
first source search realized with the complete HAWC detector. Realized with 507
days of data and represents the most sensitive TeV survey to date for such a
large fraction of the sky. A total of 39 sources were detected, with an
expected contamination of 0.5 due to background fluctuation. Out of these
sources, 16 are more than one degree away from any previously reported TeV
source. The source list, including the position measurement, spectrum
measurement, and uncertainties, is reported. Seven of the detected sources may
be associated with pulsar wind nebulae, two with supernova remnants, two with
blazars, and the remaining 23 have no firm identification yet.Comment: Submitted 2017/02/09 to the Astrophysical Journa
The formation of sunspot penumbra. I. Magnetic field properties
We study the formation of a sunspot penumbra in the active region NOAA11024.
We simultaneously observed the Stokes parameters of the photospheric iron lines
at 1089.6 nm with the TIP and 617.3 nm with the GFPI spectropolarimeters along
with broad-band images using G-band and CaIIK filters at the German VTT. The
formation of the penumbra is intimately related to the inclined magnetic field.
Within 4.5 h observing time, the magnetic flux of the penumbra increases from
9.7E+20 to 18.2E+20 Mx, while the magnetic flux of the umbra remains constant
at about 3.8E+20 Mx. Magnetic flux in the immediate surroundings is
incorporated into the spot, and new flux is supplied via small flux patches
(SFPs), which on average have a flux of 2-3E+18 Mx. The spot's flux increase
rate of 4.2E+16 Mx/s corresponds to the merging of one SFP per minute. We also
find that during the formation of the spot penumbra: a) the maximum magnetic
field strength of the umbra does not change, b) the magnetic neutral line keeps
the same position relative to the umbra, c) the new flux arrives on the
emergence side of the spot while the penumbra forms on the opposite side, d)
the average LRF inclination of the light bridges decreases from 50 to 37 deg,
and e) as the penumbra develops, the mean magnetic field strength at the spot
border decreases from 1.0 to 0.8 kG. The SFPs associated with elongated
granules are the building blocks of structure formation in active regions.
During the sunspot formation, their contribution is comparable to the
coalescence of pores. A quiet environment in the surroundings is important for
penumbral formation. As remnants of trapped granulation between merging pores,
the light bridges are found to play a crucial role in the formation process.
They seem to channel the magnetic flux through the spot during its formation.
Light bridges are also the locations where the first penumbral filaments form.Comment: 14 pages, 12 figures, accepted by A&
- …