The literature shows associations between maternal exposures to PM
and adverse pregnancy outcomes. There are few data from Latin America. We have examined PM
and pregnancy outcomes in Lima. The study ...included 123,034 births from 2012 to 2016, at three public hospitals. We used estimated daily PM
from a newly created model developed using ground measurements, satellite data, and a chemical transport model. Exposure was assigned based on district of residence (n = 39). Linear and logistic regression analyzes were used to estimate the associations between air pollution exposure and pregnancy outcomes. Increased exposure to PM
during the entire pregnancy and in the first trimester was inversely associated with birth weight. We found a decrease of 8.13 g (-14.0; -1.84) overall and 18.6 g (-24.4, -12.8) in the first trimester, for an interquartile range (IQR) increase (9.2 µg/m
) in PM
. PM
exposure was positively associated with low birth weight at term (TLBW) during entire pregnancy (OR: 1.11; 95% CI: 1.03-1.20), and at the first (OR: 1.11; 95% CI: 1.03-1.20), second (OR: 1.09; 95% CI: 1.01-1.17), and third trimester (OR: 1.10; 95% CI: 1.02-1.18) per IQR (9.2 µg/m
) increase. Higher exposure to PM
was also associated with increased risk of small for gestational age (SGA). There were no statistically significant associations between PM
exposure and preterm births (PTB). Exposure to higher concentrations of PM
in Lima may decrease birth weight and increase the frequency of TLBW and SGA. Our study was inconsistent with the literature in finding no associations with preterm birth.
Aims
Purple corn (Zea mays var. purple amylaceum) is a native variety of the Peruvian Andes, cultivated at 3000 m since the pre‐Inca times without N fertilization. We aimed to isolate and identify ...native plant growth‐promoting rhizobacteria (PGPR) for future microbial‐based inoculants.
Methods and Results
Eighteen strains were isolated from the rhizosphere of purple corn plants grown without N fertilization in Ayacucho (Peru). The 16S rRNA gene clustered the 18 strains into nine groups that contained species of Bacillus, Stenotrophomonas, Achromobacter, Paenibacillus, Pseudomonas and Lysinibacillus. A representative strain from each group was selected and assayed for N2 fixation, phosphate solubilization, indole acetic and siderophore production, 1‐aminocyclopropane‐1‐carboxylic acid deaminase activity and biocontrol abilities. Inoculation of purple corn plants with single and combined strains selected after a principal component analysis caused significant increases in root and shoot dry weight, total C and N contents of the plants.
Conclusions
PGPRs can support growth and crop production of purple corn in the Peruvian Andes and constitute the base for microbial‐based inoculants.
Significance and Impact of the Study
This study enlarges our knowledge on plant–microbial interactions in high altitude mountains and provides new applications for PGPR inoculation in purple amylaceum corn, which is part of the staple diet for the native Quechua communities.
Context.
The Atacama Large Millimeter/submillimeter Array (ALMA) has been in operation since 2011, but it has not yet been populated with the full suite of its planned frequency bands. In particular, ...ALMA Band 2 (67−90 GHz) is the final band in the original ALMA band definition to be approved for production.
Aims.
We aim to produce a wideband, tuneable, sideband-separating receiver with 28 GHz of instantaneous bandwidth per polarisation operating in the sky frequency range of 67−116 GHz. Our design anticipates new ALMA requirements following the recommendations of the 2030 ALMA Development Roadmap.
Methods.
The cryogenic cartridge is designed to be compatible with the ALMA Band 2 cartridge slot, where the coldest components – the feedhorns, orthomode transducers, and cryogenic low noise amplifiers – operate at a temperature of 15 K. We use multiple simulation methods and tools to optimise our designs for both the passive optics and the active components. The cryogenic cartridge is interfaced with a room-temperature (warm) cartridge hosting the local oscillator and the downconverter module. This warm cartridge is largely based on GaAs semiconductor technology and is optimised to match the cryogenic receiver bandwidth with the required instantaneous local oscillator frequency tuning range.
Results.
Our collaboration has resulted in the design, fabrication, and testing of multiple technical solutions for each of the receiver components, producing a state-of-the-art receiver covering the full ALMA Band 2 and 3 atmospheric window. The receiver is suitable for deployment on ALMA in the coming years and it is capable of dual-polarisation, sideband-separating observations in intermediate frequency bands spanning 4−18 GHz for a total of 28 GHz on-sky bandwidth per polarisation channel.
Conclusions.
We conclude that the 67−116 GHz wideband implementation for ALMA Band 2 is now feasible and that this receiver provides a compelling instrumental upgrade for ALMA that will enhance observational capabilities and scientific reach.
The NIH Stroke Scale (NIHSS) is used to assess acute ischemic stroke severity and outcome. High NIHSS scores are usually associated with arterial occlusion but it is unknown what the effect of time ...to clinical evaluation (TTCE) in this association is. We tested the NIHSS scores as an instrument to determine vessel occlusion (VO) at different time points from symptom onset.
Patients were selected from our prospective stroke database if they had admission NIHSS scores and intracranial vessel neuroimaging studies. We dichotomized patients according to VO and TTCE. Receiver operating curves, c statistics, and odds ratios were calculated to study the validity of the NIHSS score.
Among 463 patients (mean age 70.2 years, 53.1% male, median NIHSS 4, median TTCE 3.3 hours), 22.5% had arterial occlusion. Median NIHSS scores were higher in patients with VO, 10.5 (interquartile range 5-18) vs 3 (2-7), p<0.001, and in those with TTCE<6 hours, 15 (interquartile range 7-19) vs 4 (2-8) if ≥6 hours, p<0.001. Receiver operating characteristic curves showed that the validity of NIHSS in predicting VO was higher in patients with TTCE<6 hours, p=0.03. The best cutoff point in patients evaluated before 6 hours was an NIHSS of 7 (76.2% sensitivity, specificity 70.1%), while in patients evaluated after 6 hours the best cutoff point was 4 (sensitivity 65.4%, specificity 62.0%).
Our study shows that the validity of NIHSS scores in predicting arterial occlusion is time-dependent, decreasing with increasing time from symptom onset to clinical evaluation.
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•Gold nanoparticles tune the selectivity of TiO2 for ethanol condensation.•Untreated TiO2 is selective for intra- and inter-molecular dehydration reactions.•Gold nanoparticles promote ...dehydrogenation and condensation pathways.•This effect is more marked in presence of hydrogen.
This article analyses the role of gold nanoparticles supported on TiO2 for the gas-phase ethanol condensation. Previously, the original P25 surface was modified for increasing the Au-Ti interaction, in order to minimize the thermal deactivation. Catalysts were tested both in absence and presence of hydrogen (523–673K, WHSV=7.9h−1; yEtOH=0.32; yH2=0-0.1; 0.1MPa). Parent TiO2 is mainly selective for dehydration reactions yielding diethyl ether (favoured at low temperatures) and ethylene (favoured at higher temperatures). The presence of Au in the catalyst promotes dehydrogenation pathways, yielding acetaldehyde, as well as condensation products (mainly butanol, with selectivities close to 10%). According to DRIFT spectroscopy results, the strong ethanol adsorption on the TiO2 surface justifies the low yields and the high relevance of side-reactions produced by inter- or intra- molecular dehydration routes (diethyl ether, and ethylene formation). The gold addition minimizes this adsorption and enhances the main route by a double role: an improvement in the dehydrogenation rate (yielding more acetaldehyde) and an enhancement in the hydrogenation steps.
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•Plasma and chemical functionalization allowed cellular response on dental zirconia.•Both treatments showed similar cellular adhesion and spreading.•Inert biomaterials surfaces can be ...modified to improve bioactivity.
Zirconia is an inert implantable biomaterial with poor or null cell response. To enhance this condition of inertness, surface modification can be used to induce bioactivity improving the implant-tissue interaction. For bioactivation, a zirconia surface was modified by means of two treatments, one with argon plasma and the other with calcium and phosphate ions in addition to plasma. In vitro tests were performed to determine cell response on both surfaces and on a control. The results showed similar evidence of bioactivation in the treated samples. The novelty of this paper lies in the cellular response studies carried out in zirconia treated surfaces with two different bioactivation processes and its comparative evaluation, including cell viability, morphology and spreading. To our knowledge, no prior studies have reported these experiments, which may have many applications in the field of biomaterials.
IntroductionThere have been no time-series studies of air pollution in Peru. Here we evaluate the effect of ambient PM2.5 on emergency room (ER) visits in Lima.MethodsWe estimated daily PM2.5 levels ...at a 1 km2 resolution during 2010–2016 using ground measurements, satellite data, and chemical transport model simulations. Population-weighted average daily PM2.5 levels were calculated for each district in Lima (n = 40), and assigned to patients based on residence. ER visits for respiratory and circulatory diseases were gathered from nine large public hospitals. Poisson regression was used to estimate the rate ratio for daily ER visits with change in daily PM2.5, controlling for meteorology, time trends, and district.ResultsFor each interquartile range (IQR) increase in PM2.5, respiratory disease ER visits increased 4% (95% CI: 0–5%), stroke visits 10% (3–18%), and ischemic heart disease visits (adults, 18–64 years) 11% (−1, 24%). Districts with higher poverty showed significantly stronger associations of PM2.5 and respiratory disease ER visits than districts with lower poverty. Effects were diminished 24–42% using Lima-wide instead of district-specific PM2.5 levels.ConclusionsShort-term exposure to ambient PM2.5 is associated with increases in ER visits in Lima for respiratory diseases and stroke, and among middle-aged adults, ischemic heart disease.
Aim: This study aimed to study the prevalence of vitamin D deficiency, assessing the influence of sex, age, and season of the year.
Methods: A cross-sectional study was conducted with 1329 healthy ...subjects (668 women and 661 men) aged 18-89 years in Santiago, Chile. Age (years), body mass index, medical history, working status, sex, and date of blood sample were collected.
Results: Men were slightly older than women (53.1 ± 18.2 vs. 50.0 ± 15.6 years; p < 0.01) and a higher percentage worked outside the home (73.1% vs. 51.9%, p < 0.001). The mean serum concentration of 25-hydroxyvitamin D (25(OH)-D) was 23.3 ± 9.3 ng/ml in women and 20.9 ± 9.5 ng/ml in men (p < 0.001). The levels of 25(OH)-D by season were 26.7 ± 9.0, 23.6 ± 9.7, 19.4 ± 8.5, and 19.1 ± 9.5 ng/ml (for summer, fall, winter, and spring, respectively; p < 0.05). The prevalence of vitamin D deficiency increases with age, rising from 36.5% under 40 years to 48.0% over 60 years (p < 0.004). Male sex, winter and spring, and age showed negative correlation with levels of 25(OH)-D (p < 0.05). Multivariate linear regression showed a final model that incorporates: age (coefficient: −0.06; 95% confidence interval CI: −0.09 to −0.03; p < 0.001), male sex (coefficient: −2.00; 95% CI: −2.96 to −1.05; p < 0.001), summer (coefficient: 7.30; 95% CI: 6.17 to 8.43; p < 0.001), and fall (coefficient: 4.27; 95% CI: 3.04 to 5.50; p < 0.001).
Conclusions: Vitamin D deficiency is more prevalent in men than in women, in the elderly, and during the winter and spring seasons.
The COVID-19 pandemic will likely take years to control globally, and constant epidemic surveillance will be required to limit the spread of SARS-CoV-2, especially considering the emergence of new ...variants that could hamper the effect of vaccination efforts. We developed a simple and robust –
Phone Screen Testing
(
PoST
) – method to detect SARS-CoV-2-positive individuals by RT-PCR testing of smartphone screen swab samples. We show that 81.3–100% of individuals with high-viral-load SARS-CoV-2 nasopharyngeal-positive samples also test positive for
PoST
, suggesting this method is effective in identifying COVID-19 contagious individuals. Furthermore, we successfully identified polymorphisms associated with SARS-CoV-2 Alpha, Beta, and Gamma variants, in SARS-CoV-2-positive
PoST
samples. Overall, we report that
PoST
is a new non-invasive, cost-effective, and easy-to-implement smartphone-based smart alternative for SARS-CoV-2 testing, which could help to contain COVID-19 outbreaks and identification of variants of concern in the years to come.
•Compressive strength of foamed concrete significantly depends on cement and foam content.•Increasing the volume of EPS results in lower thermal conductivity and fire resistance.•The EPS volume ...substantially affects the compressive strength of EPS concrete.
This paper deals with the contribution of expanded polystyrene (EPS) particles on fire resistance, thermal conductivity and compressive strength of foamed concrete. The foamed (FC) and polystyrene foamed (PFC) concrete were designed for densities ranging from 1200kg/m3 to 150kg/m3 with an EPS volume range of 0–82.22% and water-cement ratio of 0.33. The foamed concrete (FC) with a density of 800kg/m3 and an EPS volume of 0% was designed as reference for polystyrene foamed concrete. The results indicated that increasing the volume of EPS causes a significant reduction of thermal conductivity, fire endurance and compressive strength of concrete.
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