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The east of Cali is composed of loose sand deposits with high water table levels. This condition and the high seismic hazard of the city make cyclic liquefaction one of the main hazards in the city, which may affect more than 600,000 citizens and important infrastructures such as the city’s main drinking water treatment plants. Therefore, it was decided to design and implement a seismic monitoring center to study the behavior of liquefiable soils under local seismogenic conditions, in which subduction earthquakes predominate. First, more than 130 earthquakes from two seismic monitoring centers with liquefiable layers in the USA were studied to determine the requirements for the adequate design of the monitoring center. Then, a robust geotechnical and seismic characterization of the study area including SPT, CPTu, and seismic and ambient noise tests were carried out. From this information, the specifications and location of the instruments and, in general, the characteristics of the monitoring center were defined. The monitoring center has been planned to be established in two stages, and the first one has already been built and commissioned. The implementation of the first stage allowed to adequately record 35 earthquakes from different seismogenic sources, most of them from subduction earthquakes, and to verify that the potentially liquefiable layer remains saturated throughout the year. Subsequent ground motion sensors will allow to deeply study and understand large shear strains and excess pore pressures generation in the soil deposit, as well as their relationships with different intensity measures. The experience shared herein can benefit the design, construction, and operation of other seismic monitoring centers across the world.

Pediatric patients on maintenance hemodialysis (HD) are at risk of both malnutrition and fluid overload. This pilot study aimed to assess correlates of normalized protein catabolic rate (nPCR) in adolescents on chronic HD, in particular fluid status markers. All patients aged 10–18 years on chronic HD in our center between 2017 and 2019 were enrolled. For each patient, mean nPCR was calculated and correlations with the following parameters investigated: dry body weight change in subsequent 3 months in kg (∆BW) and percentage of BW (∆BW%), change in body mass index (∆BMI), preHD systolic and diastolic blood pressure (SBP, DBP), residual urine output, biochemistry, and blood volume monitoring–derived first hour refill index (RI), calculated as ratio between ultrafiltration rate and reduction in relative blood volume in first hour of dialysis. Seventy-nine nPCR determinations were collected in 23 patients, median age 14.8 years. nPCR significantly correlated with ∆BW, ∆BW%, ∆BMI, spKT/V, and preHD serum creatinine, and negatively correlated with age, DBP SDS (r=−0.466, p=0.025) and RI (r=−0.435, p=0.043). RI was significantly higher in patients with nPCR

The capillary infiltration of the Zn-22Al-2Cu (Zinalco) alloy into NaCl packed particles of sizes 496, 687, and 945 μm was studied using centrifugal casting. The threshold pressure for infiltration of NaCl particles with Zinalco was deduced experimentally, which increased as the diameter of the particles decreased. The work of immersion was determined from the threshold pressure with a value of 2.1. The infiltration proceeded at distinctly different rates for the three particle sizes studied. An equation to predict the threshold pressure to infiltrate Zinalco alloy into NaCl particles for given particle size and volume fraction was established. The micromechanical analysis showed that the strength of the foam depended strongly on the level of infiltration of the derived foam. As the level of infiltration increased, the stress distribution in the foams produced became homogeneously distributed in all the struts that make up the cell, which increases the strength of foam. The elastic modulus of the as-produced Zinalco foams is governed by structural parameters such as the pore size and the strut length. Thinner and shorter struts in the foam increase its ability to resist elastic deformation in the foam.

The influence of hospital-related factors on outcomes following colorectal surgery is not well-established. The aim of our study was to evaluate the relationship between hospital factors on outcomes in surgically managed colorectal cancer patients. We performed a 2-year (2014–2015) analysis of the NIS database. Adult (> 18 years) patients who underwent open or laparoscopic colorectal resection were identified using ICD-9 codes. Patients were stratified based on hospital: volume (low vs. high), teaching status, and location (urban vs. rural). Outcome measures were complications and mortality. Multivariate logistic regression was performed. A total of 153,453 patients with CRC were identified of which 35.3% underwent surgical management. Mean age was 69 ± 13 years, 51.6% were female, and 67% were white. Twenty-seven percent of the patients were managed at a high-volume center, 48% at intermediate-volume center while 25% at a low-volume center. Complications and mortality rates were lower in patients who were managed at high-volume centers and urban hospitals, while no difference was noticed based on teaching status. On regression analysis, patients managed at high-volume centers (OR 0.76 [0.56–0.89]) and urban hospitals (OR 0.83 [0.64–0.91]) have lower odds of complications; similarly, high-volume centers (OR 0.79 [0.65–0.90]) and urban facility (OR 0.87 [0.70–0.92]) were associated with lower odds of mortality. However, there was no association between teaching status and outcomes. Hospital factors significantly influence outcomes in patients with CRC managed surgically. High-volume centers and urban facilities have relatively better outcomes. Regionalization of care along with the appropriate availability of resources may improve outcomes in patients with CRC. Level III, Retrospective Observational Study

The incidence in young patients has increased significantly over the last few decades. The aim of this study is to evaluate demographic and tumor characteristics of young patients and analyze the short-term surgical outcomes of patients undergoing surgery. We performed a 2-year review (2015–2016) of the ACS-NSQIP and included all patients with CC who underwent surgical management. Patients were stratified into two groups: early-onset CC (

To review the pathophysiology, presentation, and treatment of neuromyelitis optica spectrum disorder (NMOSD) and its association with systemic lupus erythematosus (SLE) and Sjogren's syndrome (SS). NMOSD is an autoimmune disorder of the central nervous system that primarily targets astrocytes. Although the prevalence is unknown, the coexistence of NMOSD and SLE/SS is well-recognized. Patients with both NMOSD and SLE or SS require may require unique approaches to diagnosis and management. Coexistence of NMOSD and SLE/SS is important for the rheumatologist and neurologist to be able to recognize. For the rheumatologist, NMOSD and its neurologic symptoms represent a distinct disease process from neurologic complications of the patient’s underlying connective tissue disease, and it requires distinct acute and chronic management. For the neurologist, the coexistence of SLE and SS can help to establish a diagnosis of NMOSD, or in some situations, the development of neurologic symptoms secondary to NMOSD can lead to the diagnosis of connective tissue disease.

In this work, the effects of the slag basicity (mass ratio CaO to SiO2) and the addition of FeSO4 or FeS2 into the slag on the stability of the mineralogical species in the slag containing chromium compounds were studied. The chemical stability was evaluated by leaching the slags with an acid solution. The main Cr-compounds in slags with low basicity (CaO/SiO2 = 1) and FeSO4 were FeCr2O4 and Ca3Cr2Si3O12, while Cr3S4 and Ca3Cr2Si3O12 were formed in slags with FeS2. The slags with high basicity (CaO/SiO2 = 2) and FeSO4 contained CaCr2O4, FeCr2O4 and Ca5(SiO4)2SO4. The slags with FeS2 and high basicity produced FeS·Cr2S3, FeCr2O4 and Ca3Cr2Si3O12. The results showed that the lowest chromium concentration levels in the leaching liquors corresponded to slags with CaO/SiO2 = 1 and high FeS2 contents, owing to the stable binding of chromium in the compounds FeCr2O4, Cr3S4 and Ca3Cr2Si3O12.

Cuphea aequipetala Cav. (Lythraceae), a species highly valued for its medicinal properties, is threatened in the wild. To provide an alternative source of material for production of bioactive compounds, we established adventitious root cultures of C. aequipetala and determined their phenolic compounds contents and antioxidant activity. Cultures were initiated from root tips of in vitro C. aequipetala plantlets and were grown in B5 or SH culture medium containing either indole butyric acid (IBA) or α-naphthalene acetic acid at 0, 5 or 10 µM. The maximum root biomass (1.6 g/L dry mass (DM) per L medium) was recorded after 14 days of growth in B5 + 5 µM IBA. Roots in B5 medium remained green, whereas they tended to oxidize in SH medium. The highest contents of total phenolic compounds (9.1 ± 0.1 µg gallic acid equivalents/g DM) and flavonoids (37.5 ± 0.7 µg quercetin equivalents/g DM) were in roots grown in B5 + 5 µM IBA after 14 days of growth. Root cultures accumulated mainly flavan-3-ols, whereas roots or leaves from whole plants accumulated mainly flavonols. We analyzed the antioxidant properties of root extracts using in vitro assays. Roots grown in B5 medium showed stronger free-radical scavenging activity than that of roots grown in SH medium. Our results show that adventitious root cultures of C. aequipetala are a promising system for research on antioxidant compounds biosynthesis and for scaled-up production of useful biological materials.

In biomedical research, it is often of interest to characterize biologic processes giving rise to observations and to make predictions of future observations. Bayesian nonparametric methods provide a means for carrying out Bayesian inference making as few assumptions about restrictive parametric models as possible. There are several proposals in the literature for extending Bayesian nonparametric models to include dependence on covariates. Limited attention, however, has been directed to the following two aspects. In this article, we examine the effect on fitting and predictive performance of incorporating covariates in a class of Bayesian nonparametric models by one of two primary ways: either in the weights or in the locations of a discrete random probability measure. We show that different strategies for incorporating continuous covariates in Bayesian nonparametric models can result in big differences when used for prediction, even though they lead to otherwise similar posterior inferences. When one needs the predictive density, as in optimal design, and this density is a mixture, it is better to make the weights depend on the covariates. We demonstrate these points via a simulated data example and in an application in which one wants to determine the optimal dose of an anticancer drug used in pediatric oncology.

Smallholder farmers need information on plant diseases. Ten plant health clinics (Postas para Plantas) evolved in Bolivia after 2000 and are still operating due to the efforts of three local institutions. The plant clinics receive any problem, on any crop, and give written and verbal recommendations, immediately if possible. Many clinics are held at weekly farm fairs, where villagers from many surrounding communities can seek help. The clinic staff write fact sheets for farmers on common problems. From 2000 to early 2009 the clinics received more than 9000 queries on over 100 crops with potato comprising two thirds of the queries, followed by peach, tomato and broad bean. Potato tuber moth and potato weevil were by far the most dominant plant health problems in the high Andes, but not in lowland areas. The diversity of crops and problems are a big challenge to the clinic staff. With basic training and practical experience they learn to diagnose most problems. However, they need access to expert support to solve some of the more difficult problems and improve the quality of advice. Preliminary results show cases of poverty alleviation, reduction in pesticide abuse, increased harvests and other benefits. The plant health clinics in Bolivia enabled extension and research to reach more farmers with a timely low-cost service.

Lead is an engineering material used mainly in the manufacturing of lead-acid batteries for the automotive industry. Lead recovery from exhausted batteries is carried out by the pyrometallurgical route by injecting sulfur the powder reagent through a lance into the lead bath. In this work a mathematical simulation was carried out on the copper drossing process with the software COMSOL 3.4. A kinetic study of the injection process of the lance-kettle system was carried out. The copper concentration profiles were obtained according with the injection rate of the particles. The best conditions for the copper drossing process were an injection rate of 3.31 m/s at 380°C. The modeling results were validated with experimental results obtaining good agreement.