127 research outputs found
Insights from Water Quality of High Andean Springs for Human Consumption in Perú
The headwaters of the high Andean basin in Peru accumulate water from the mist, rain,
snow, and hail, and it is transported superficially and underground to low-lying areas, mostly used
for drinkable purposes. The natural water in these areas might be altered due to legal and illegal
mining extraction. The aim of the study was to evaluate the water quality for human consumption.
Seventeen water samples were examined from Andahuaylas (A), San Jerónimo (S), Talavera (T),
and Chiara (CH) districts located between 2813 and 4004 m altitude in the Andes. We used physic ochemical, microbiological, and metal parameters, and the results were compared to permissible
levels established by the WHO and ECA-Peru to examine samples collected in the dry and rainy
seasons in 2019. Application of principal component analysis (PCA) identified areas and conditioning
parameters. Extractive mining activity influences the quality of springs due to the presence of metals,
especially antimony (Sb), arsenic (As), cadmium (Cd), and lead (Pb), values of which are higher than
values permissible for human consumption, being higher in the dry season (p < 0.05). In addition, the
presence of cations and particulate matter affects physico-chemical parameters, for example turbidity.
PCA showed that parameters for water characterization are season-independent, and water quality in
the springs would be conditioned by the presence of metals, especially in Andahuaylas and Talavera
zones, as well as the parameters that are associated with dissolved solids in the water (turbidity and
fluorides). A frequent monitoring program of springs and groundwater is recommended, with the
purpose to protect water from contamination and guarantee safe water availability in low-lying and
urbanized areas
Proposal of a water-quality index for high andean basins: application to the Chumbao river, Andahuaylas, Peru
Thewater fromthe high Andean rivers is peculiar due to its composition and the geomorphology
of its sources, and naturally or anthropogenically contamination is not discarded along its course.
This water is used for agriculture and human consumption, therefore knowing its quality is important.
This research aimed to proposing and formulate a water-quality index for high Andean basins through
the Delphimethod, and its application in the Chumbao River located in Andahuaylas-Peru. Forty-three
water-quality parameters were evaluated through the Delphi method, and the water-quality index
(WQIHA) was formulated with a weighted average of the weights of the selected parameters, it was
compared with the WQI Dinius. For this purpose, ten sampling points were considered along the
Chumbao River located between 4274 and 2572 m of altitude and theWQIHA was applied. In addition,
field and laboratory analyses were carried out in 2018, 2019, and 2021, in dry and rainy seasons. Twenty
parameters were grouped in the physicochemical sub-index (SIPC), heavy metals sub-index (SIHM),
and organic matter sub-index (SIOM). Each group contributed with weights of 0.30, 0.30, and 0.40,
respectively, for theWQIHA formulation. The SIPC and SIOM showed that the areas near the head of
the basin presented excellent and good quality, while the urbanized areas were qualified as marginal
to poor; SIHM reported good quality in all points and seasons. Regarding the WQIHA, the index
shows good quality in the zones above 3184 m of altitude, contrasting with poor quality downstream,
decreasing notably in both seasons, suggesting continuous degradation of the water body
Long-term social skills group training for children and adolescents with autism spectrum disorder: a randomized controlled trial
Social skills group training (SSGT) is widely used for intellectually able children and adolescents with autism spectrum disorder (ASD). Previous studies indicate small to moderate effects on social communication capacities. The duration of most available programs is relatively short, and extended training might lead to further improvement. This randomized controlled trial compared an extended 24-week version of the SSGT program KONTAKT with standard care. The weekly sessions gradually shifted in content from acquisition of new skills to real-world application of the acquired skills. A total of 50 participants with ASD (15 females; 35 males) aged 8–17 years were included. The study was conducted at two child and adolescent psychiatry outpatient units in Sweden. The primary outcome was the Social Responsiveness Scale–Second Edition (SRS-2) rated by parents and blinded teachers. Secondary outcomes included parent- and teacher-rated adaptive behaviors, trainer-rated global functioning and clinical severity, and self-reported child and caregiver stress. Assessments were made at baseline, posttreatment, and at 3-months follow-up. Parent-rated SRS-2 scores indicated large effects posttreatment [- 19.2; 95% CI - 29.9 to - 8.5; p < .001, effect size (ES) = 0.76], which were maintained at follow-up (- 20.7; 95% CI - 31.7 to - 9.7; p < .0001, ES = 0.82). These estimates indicate substantially larger improvement than previously reported for shorter SSGT. However, the effects on teacher-rated SRS-2 and most secondary outcomes did not reach statistical significance. Our results suggest added benefits of extended SSGT training, implying that service providers might reach better results by optimizing the delivery of SSGT
Residuos β-lactámicos y tetraciclinas en la leche fresca adquirida por Comités de Vaso de Leche de los distritos de San Jerónimo y Andahuaylas, Apurímac, Perú
The aim of this study was to evaluate the effect of the presence of residues of β- lactam antibiotics and tetracyclines, as well as the physicochemical properties of fresh milk acquired by the Glass of Milk Committees of two districts of Apurimac, Peru. Triplicate milk samples were analyzed from 37 and 32 committees in the districts of San Jerónimo and Andahuaylas respectively. Density, acidity, pH, total solids (TS) and alcohol test were determined and compared with the Peruvian Technical Standards (NTP) for fresh milk. The presence of β-lactam and tetracycline antibiotic compounds was determined through the Betastar® colorimetric kit. The physicochemical properties were correlated with the presence of antibiotics through the Pearson coefficient. A principal component analysis (PCA) was performed. Results showed that 10.8% of the milk samples from the San Jerónimo committees were positive for tetracycline, while 9.4 and 3.1% of the San Jerónimo and Andahuaylas committees, respectively, were positive for β-lactams. A high percentage of milk samples were outside the ranges established by the NTP for density, pH, acidity and TS. The PCA analysis shows that acidity and density are the main variables that would would determine the presence of antibiotics.El objetivo del trabajo fue evaluar el efecto de la presencia de residuos de antibióticos β-lactámicos y tetraciclinas, así como las propiedades fisicoquímicas de la leche fresca adquirida por los Comités de Vaso de Leche de dos distritos de Apurímac, Perú. Se analizaron muestras de leche por triplicado, provenientes de 37 y 32 comités de los distritos de San Jerónimo y Andahuaylas, respectivamente. Se determinaron las propiedades fisicoquímicas: densidad, acidez, pH, sólidos totales (ST) y prueba de alcohol, las cuales se compararon con las Normas Técnicas Peruanas (NTP) para leche fresca. La presencia de compuestos antibióticos β-lactámicos y tetraciclinas se determinó a través del kit colorimétrico Betastar®. Las propiedades fisicoquímicas se correlacionaron con la presencia de antibióticos a través del coeficiente de Pearson. Se realizó un análisis de componentes principales (ACP). El 10.8% de las muestras de leche provenientes de los comités de San Jerónimo fue positivo para tetraciclina, mientras que el 9.4 y 3.1% de los comités de San Jerónimo y Andahuaylas, respectivamente, fueron positivos para β- lactámicos. Un alto procentaje de las muestras de leche estuvieron fuera de los rangos establecidos por las NTP para densidad, pH, acidez y ST. Del análisis ACP se desprende que la acidez y la densidad son las principales variables que pemitirían determinar la presencia de antibioticos
Cerebral embolization associated with parenchymal seeding of the left atrial myxoma : Potential role of interleukin-6 and matrix metalloproteinases
Systemic embolization has been reported in up to 40% of patients with left atrial myxoma, half of them with cerebral involvement. However, development of intracerebral embolization associated with parenchymal seeding of the myxoma emboli is an extremely rare complication, with only 36 histologically diagnosed cases reported in the published literature. We describe a 69-year-old woman who arrived at the emergency service with hemiparesis associated with drug-resistant epilepsy and a medical history of resection of a left atrial myxoma 10 months previously. Cranial computed tomography revealed multiple large lesions of heterogeneous density and cystic components in the occipital lobes and posterior fossa parenchyma. Histopathological analyses after stereotactic biopsy of the occipital lesion revealed infiltrative myxoma cells with benign histological findings and uniform expression of calretinin similar to that of the primary cardiac myxoma. Additional immunohistochemical studies confirmed brain parenchymal seeding of the myxoma cells with strong expression of interleukin-6 (IL-6) and focal expression of matrix metalloproteinases-2 (MMP-2). Here, we discuss the clinicopathological features of intracerebral embolization of left atrial myxomas associated with progressive parenchymal seeding of the tumor emboli and the potential pathogenic role of IL-6 and MMPs.Peer reviewe
Evaluación de las isotermas de sorción de granos y harina de kiwicha (Amaranthus caudatus)
The main objective was to evaluate the adsorption isotherms of grain and flour amaranth (Amaranthus caudatus) varieties Oscar White, Noel Vietmeyer and CICA, it was used gravimetric method for static intervals relative humidity 10 to 90% at temperatures of were studied 11 mathematical models and they were modeled to experimental data through RNL, taking as a convergence criterion the correlation coefficient R2 and the average relative error %E, thus the model of Adam and Shove present best fit for grains of amaranth, while the flour was Peleg model. Was also observed that the storage temperature influences significantly (p value<0.05) in the equilibrium moisture (Xe) grain and flour amaranth. The heat isosteric of adsorption oscillates between 6.340 to 0.235 kJ/g for moisture content of 0.06 to 0.15 g/g m.s. for the variety grain Oscar Blanco, for variety Noel Vietmeyer oscillates between 2.556 to 0.518 kJ/g for moisture of 0.04 to 0.12 g/g m.s., and for grain CICA of 4.645 to 0.176 kJ/g for moisture of 0.06 to 0.14 g/g m.s, as for the flour of the variety Oscar Blanco is between 32.028 to 1.99 kJ/g for moisture content of 0.05 to 0.12 g /g m.s, and for variety Noel Vietmeyer of 26.992 to 0.648 kJ/g for moisture of de 0.06 to 0.20 g/g m.s.O objetivo principal foi avaliar as isotermas de sorção de grãos e farinha de amaranto (Amaranthus caudatus) das variedades Oscar Blanco, Noel Vietmeyer e CICA, utilizou-se o método estático gravimétrico para intervalos de humidade relativa de 10 a 90% a temperaturas de 18, 20, 25 e 30 °C. Estudaram-se 11 modelos matemáticos e modelaram-se a dados experimentais através de RNL tomando como critério de convergência o coeficiente de correlação R2 e o erro médio relativo %E, assim o modelo de Aldam e Shove apresento melhor ajuste para os grãos de amaranto, enquanto para a farinha foi o modelo de Peleg. Assim mesmo observou-se que a temperatura de armazenamento influi significativamente (p-value<0,05) na humidade de equilíbrio (Xe) dos grãos e farinha de amaranto. O calor isostérico de sorção varia entre 6,340 a 0,235 KJ/g para humidades de 0,06 a 0,15 g de água/g m.s. para os grãos da variedade Oscar Blanco, para a variedade Noel Vietmeyer varia entre 2,556 a 0,518 KJ/g para humidades de 0,04 a 0,12 g de água/g m.s., e para o grão CICA de 4,645 a 0,176 KJ/g para humidades de 0,06 a 0,14 g de água/g m.s., enquanto para a farinha da variedade Oscar Blanco encontra-se entre 32,028 a 1,99 KJ/g para humidades de 0,05 a 0,12 g de água/g m.s., e para a variedade Noel Vietmeyer de 26,992 a 0,648 KJ/g para humidades de 0,06 a 0,20 g de água/g m.s.El objetivo principal fue evaluar las isotermas de sorción de granos y harina de kiwicha (Amaranthus caudatus) de las variedades Oscar Blanco, Noel Vietmeyer y CICA, se utilizó el método estático gravimétrico para intervalos de humedad relativa de 10 a 90% a temperaturas de 18, 20, 25 y 30 °C. Se estudiaron 11 modelos matemáticos y se modelaron a datos experimentales a través de RNL tomando como criterio de convergencia el coeficiente de correlación R2 y el error medio relativo %E, así el modelo de Adam y Shove presentó mejor ajuste para los granos de kiwicha, mientras que para la harina fue el modelo de Peleg. Asimismo, se observó que la temperatura de almacenamiento influye significativamente (p-value<0,05) en la humedad de equilibrio (Xe) de los granos y harina de kiwicha. El calor isostérico de adsorción oscila entre 6,340 a 0,235 KJ/g para humedades de 0,06 a 0,15 g de agua/g m.s. para los granos de la variedad Oscar Blanco, para la variedad Noel Vietmeyer oscila entre 2,556 a 0,518 KJ/g para humedades de 0,04 a 0,12 g de agua/g m.s., y para el grano CICA de 4,645 a 0,176 KJ/g para humedades de 0,06 a 0,14 g de agua/g m.s, en tanto que para la harina de la variedad Oscar Blanco se encuentra entre 32,028 a 1,99 KJ/g para humedades de 0,05 a 0,12 g de agua/g m.s., y para la variedad Noel Vietmeyer de 26,992 a 0,648 KJ/g para humedades de 0,06 a 0,20 g de agua/g m.s
Galaxy populations in the Hydra i cluster from the VEGAS survey:I. Optical properties of a large sample of dwarf galaxies
At ~50 Mpc, the Hydra I cluster of galaxies is among the closest cluster in
the z=0 Universe, and an ideal environment to study dwarf galaxy properties in
a cluster environment. We exploit deep imaging data of the Hydra I cluster to
construct a new photometric catalog of dwarf galaxies in the cluster core,
which is then used to derive properties of the Hydra I cluster dwarf galaxies
population as well as to compare with other clusters. Moreover, we investigate
the dependency of dwarf galaxy properties on their surrounding environment. The
new Hydra I dwarf catalog contains 317 galaxies with luminosity between
-18.5<<-11.5 mag, a semi-major axis larger than ~200 pc (a=0.84 arcsec),
of which 202 are new detections, previously unknown dwarf galaxies in the Hydra
I central region. We estimate that our detection efficiency reaches 50% at the
limiting magnitude =-11.5 mag, and at the mean effective surface
brightness =26.5 mag/. We present the standard
scaling relations for dwarf galaxies and compare them with other nearby
clusters. We find that there are no observational differences for dwarfs
scaling relations in clusters of different sizes. We study the spatial
distribution of galaxies, finding evidence for the presence of substructures
within half the virial radius. We also find that mid- and high-luminosity
dwarfs (<-14.5 mag) become on average redder toward the cluster center,
and that they have a mild increase in with increasing clustercentric
distance, similar to what is observed for the Fornax cluster. No clear
clustercentric trends are reported with surface brightness and S\'ersic index.
Considering galaxies in the same magnitude-bins, we find that for high and
mid-luminosity dwarfs (<-13.5 mag) the g-r color is redder for the
brighter surface brightness and higher S\'ersic n index objects.Comment: Accepted for publication in A&A. 25 pages, 21 figure
KONTAKT© for Australian adolescents on the autism spectrum: protocol of a randomized control trial
Slow Spin Relaxation in Two-Dimensional Electron Systems with Antidots
We report a Monte Carlo investigation of the effect of a lattice of antidots
on spin relaxation in twodimensional electron systems. The spin relaxation time
is calculated as a function of geometrical parameters describing the antidot
lattice, namely, the antidot radius and the distance between their centers. It
is shown that spin polarization relaxation can be efficiently suppressed by the
chaotic spatial motion due to the antidot lattice. This phenomenon offers a new
approach to spin coherence manipulation in spintronics devices.Comment: submitted to Phys. Rev.
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