147 research outputs found
Vibratory Neurostimulator for Patients with Essential Tremor
The present research shows a prototype that seeks the suppression of essential tremor in a neuroprosthesis that emits vibrations to saturate the channels of communication of this pathology, initially presents a general concept of the disease, and the treatments that seek to correct this symptom known as tremor. It was essential to follow the general outlines of the design and development of the device, and subsequently the results obtained and conclusions that validate the hypotheses raised, the authors propose a series of works that validate the system and the hypotheses itself.
 
Methodology of Construction of an Algorithm for the Systemic Learning of First Semester Students of the TICs Subject
Algorithms have become the primary source to start programming. Particularly, making an algorithm from a given problem and converting it into a program is of great importance for analysts, technologists, and computer engineers, that is why this article aims to give a clear idea of how to develop an algorithm for any given problem. The objective of this work was to develop a methodology that is not so complex and that allows our students to perform the algorithm, pseudo-code, flow diagram and finally be able to carry out the program. The tests carried out show that the methodology used gives good results, achieving a significant improvement in the learning of students in the first semester of industrial engineering.
Keywords: algorithms, flow diagrams, program, programming, software engineerin
Effect of Threonine and the Bioactive Component of Saccharomyces Cerevisiae on the Productive Performance of the Broiler Cobb 500
This study was conducted in Chimborazo province, Riobamba Canton to evaluate the effect of threonine and the bioactive component of Saccharomyces cerevisiae on the productive performance of the broiler Cobb 500. A total of 270 one-day-old broiler chicken of both sexes were included, which corresponded to an experimental unit size of 15 birds. Two growth promoters were used for the treatments -- T1: Threonine (aminoacid) 200 g/Tn; and T2: bioactive oligosaccharides, obtained from the cell wall of selected strains of S. Cerevisiae (probiotic) 750 g/Tn. These were compared to a control group. The data were analyzed through Analysis of Variance (ADEVA). The separation of means was performed using the Tukey statistic at a level of significance of p < 0.05 and p < 0.01. The data were processed using the Infostat software version 2010. The results showed that the best productive yields were with treatment 2; the values for this treatment were: weight at 28 days: 1369.42 g; weight gain at 28 days: 48.90 g; food conversion at 28 days: 1.39 points; carcass weight: 2527.05 g; and yield to the carcass: 83.85%. Through the economic analysis, it was determined that the highest cost-benefit index was 1.30 USD with the application of T2. So according to the results, a better use of the nutrients that are present in the feed is achieved when bioactive components of S. cerevisiae are supplied in the diet of broiler chickens.
Keywords: Threonine, Saccharomyces cerevisiae, productive performance, broiler, Cobb 500.
RESUMEN
Se realizó un experimento en la provincia de Chimborazo, Cantón Riobamba, para evaluar los efectos de treonina y componentes bioactivos de Saccharomyces cerevisiae sobre el comportamiento productivo en aves Cobb 500. Se utilizaron 270 pollitos mixtos Cobb 500 de un día de edad de ambos sexos, con un tamaño de unidad experimental de 15 aves. Para los tratamientos se manejaron dos promotores de crecimiento, T1: Treonina (aminoácido) 200 g/Tn y T2: Oligosacáridos bioactivos, obtenidos a partir de la pared celular de cepas seleccionadas de S. Cerevisiae750 g/Tn; frente a un testigo (T0). Los datos obtenidos fueron sometidos a Análisis de Varianza (ADEVA); la separación de medias se realizó mediante el estadístico Tukey a un nivel de significancia (p < 0,05) y (p < 0,01); los datos se procesaron mediante el software Infostat versión 2010. Los resultados muestran los mejores rendimientos productivos con el Tratamiento 2, para los parámetros: peso a los 28 días 1369,42 g; ganancia de peso a los 28 días 48,90 g; y conversión alimenticia a los 28 días con 1,39 puntos; así como peso a la canal 2527,05 g; y rendimiento a la canal 83,85%. Mediante el análisis económico se determinó que el mayor índice beneficio costo fue de 1,30 USD con la aplicación del T2. Lo que brinda un indicativo que mediante el suministro de componentes bioactivos de S. cerevisiae en la dieta de pollos broiler, se logra un mejor aprovechamiento de los nutrientes que se encuentran presentes en el alimento, lo que se refleja en los parámetros productivos.
Palabras clave: treonina, Saccharomyces cerevisiae, comportamiento productivo, broilers, Cobb 500
The Twisted Magnetic Field of the Protobinary L483
We present H-band (1.65 μm) and SOFIA HAWC+ 154 μm polarization observations of the low-mass core L483. Our H-band observations reveal a magnetic field that is overwhelmingly in the E–W direction, which is approximately parallel to the bipolar outflow that is observed in scattered IR light and in single-dish 12CO observations. From our 154 μm data, we infer a ∼45° twist in the magnetic field within the inner 5″ (1000 au) of L483. We compare these new observations with published single-dish 350 μm polarimetry and find that the 10,000 au scale H-band data match the smaller-scale 350 μm data, indicating that the collapse of L483 is magnetically regulated on these larger scales. We also present high-resolution 1.3 mm Atacama Large Millimeter/submillimeter Array data of L483 that reveals it is a close binary star with a separation of 34 au. The plane of the binary of L483 is observed to be approximately parallel to the twisted field in the inner 1000 au. Comparing this result to the ∼1000 au protostellar envelope, we find that the envelope is roughly perpendicular to the 1000 au HAWC+ field. Using the data presented, we speculate that L483 initially formed as a wide binary and the companion star migrated to its current position, causing an extreme shift in angular momentum thereby producing the twisted magnetic field morphology observed. More observations are needed to further test this scenario
Potential use of deodorised water extracts: polyphenol-rich extract of Thymus pannonicus All. as a chemopreventive agent
Deodorised water extracts of aromatic plants are obtained as by-products of essential oil isolation and usually discarded as waste. However, phytochemical composition of these extracts encourages their further utilization as food additives or functional food ingredients. In this study we investigated phytochemical composition, antioxidant and in vivo antiproliferative activity of deodorised water extract of Thymus pannonicus All. (DWE). HPLC analysis revealed rosmarinic acid (RA) (71.11 +/- 1.54 mg/g) as the most abundant constituent of the extract, followed by salvianolic acid H (14.83 +/- 0.79 mg/g, calculated as RA). DWE exhibited pronounced antioxidant activity in vitro, in FRAP and DPPH tests (FRAP value: 7.41 mmol Fe/g and SC50: 3.80 mu g/g, respectively). Using the model of Ehrlich carcinoma cells in mice that were treated with DWE prior, at the time, and after tumour cells implantation, the tumour growth suppression and redox status of malignant cells (i.e., activities of antioxidant enzymes, level of glutathione and intensity of lipid peroxidation) were followed. DWE applied as pretreatment caused disturbance of antioxidant equilibrium as well as apoptosis/necrosis of up to 90% EAC cells. Results obtained in the present study revealed chemopreventive potential and possibility of T. pannonicus DWE usage. High content of RA and other phenolic compounds explains, at least in part, the observed effects
A comparative analysis reveals weak relationships between ecological factors and beta diversity of stream insect metacommunities at two spatial levels.
The hypotheses that beta diversity should increase with decreasing latitude and increase with spatial extent of a region have rarely been tested based on a comparative analysis of multiple datasets, and no such study has focused on stream insects. We first assessed how well variability in beta diversity of stream insect metacommunities is predicted by insect group, latitude, spatial extent, altitudinal range, and dataset properties across multiple drainage basins throughout the world. Second, we assessed the relative roles of environmental and spatial factors in driving variation in assemblage composition within each drainage basin. Our analyses were based on a dataset of 95 stream insect metacommunities from 31 drainage basins distributed around the world. We used dissimilarity-based indices to quantify beta diversity for each metacommunity and, subsequently, regressed beta diversity on insect group, latitude, spatial extent, altitudinal range, and dataset properties (e.g., number of sites and percentage of presences). Within each metacommunity, we used a combination of spatial eigenfunction analyses and partial redundancy analysis to partition variation in assemblage structure into environmental, shared, spatial, and unexplained fractions. We found that dataset properties were more important predictors of beta diversity than ecological and geographical factors across multiple drainage basins. In the within-basin analyses, environmental and spatial variables were generally poor predictors of variation in assemblage composition. Our results revealed deviation from general biodiversity patterns because beta diversity did not show the expected decreasing trend with latitude. Our results also call for reconsideration of just how predictable stream assemblages are along ecological gradients, with implications for environmental assessment and conservation decisions. Our findings may also be applicable to other dynamic systems where predictability is low
Early Planet Formation in Embedded Disks (eDisk). VII. Keplerian Disk, Disk Substructure, and Accretion Streamers in the Class 0 Protostar IRAS 16544-1604 in CB 68
We present observations of the Class 0 protostar IRAS 16544-1604 in CB 68
from the ''Early Planet Formation in Embedded Disks (eDisk)'' ALMA Large
program. The ALMA observations target continuum and lines at 1.3-mm with an
angular resolution of 5 au. The continuum image reveals a dusty
protostellar disk with a radius of 30 au seen close to edge-on, and
asymmetric structures both along the major and minor axes. While the asymmetry
along the minor axis can be interpreted as the effect of the dust flaring, the
asymmetry along the major axis comes from a real non-axisymmetric structure.
The CO image cubes clearly show the gas in the disk that follows a
Keplerian rotation pattern around a 0.14 central protostar.
Furthermore, there are 1500 au-scale streamer-like features of gas
connecting from North-East, North-North-West, and North-West to the disk, as
well as the bending outflow as seen in the CO (2-1) emission. At the
apparent landing point of NE streamer, there are SO (6-5) and SiO (5-4)
emission detected. The spatial and velocity structure of NE streamer can be
interpreted as a free-falling gas with a conserved specific angular momentum,
and the detection of the SO and SiO emission at the tip of the streamer implies
presence of accretion shocks. Our eDisk observations have unveiled that the
Class 0 protostar in CB 68 has a Keplerian rotating disk with flaring and
non-axisymmetric structure associated with accretion streamers and outflows.Comment: 30 pages, 24 figures, accepted for publication in The Astrophysical
Journal as one of the first-look papers of the eDisk ALMA Large Progra
Early Planet Formation in Embedded Disks (eDisk). II. Limited Dust Settling and Prominent Snow Surfaces in the Edge-on Class I Disk IRAS 04302+2247
While dust disks around optically visible, Class II protostars are found to
be vertically thin, when and how dust settles to the midplane are unclear. As
part of the Atacama Large Millimeter/submillimeter Array (ALMA) large program,
Early Planet Formation in Embedded Disks, we analyze the edge-on, embedded,
Class I protostar IRAS 04302+2247, also nicknamed the ``Butterfly Star." With a
resolution of 0.05" (8~au), the 1.3 mm continuum shows an asymmetry along the
minor axis which is evidence of an optically thick and geometrically thick disk
viewed nearly edge-on. There is no evidence of rings and gaps, which could be
due to the lack of radial substructure or the highly inclined and optically
thick view. With 0.1" (16~au) resolution, we resolve the 2D snow surfaces,
i.e., the boundary region between freeze-out and sublimation, for CO
=2--1, CO =2--1, CO =2--1, CO
=--, and SO =--, and constrain the CO
midplane snow line to au. We find Keplerian rotation around a
protostar of using CO. Through forward
ray-tracing using RADMC-3D, we find that the dust scale height is au
at a radius of 100~au from the central star and is comparable to the gas
pressure scale height. The results suggest that the dust of this Class~I source
has yet to vertically settle significantly.Comment: 33 pages, 21 figures. Accepted for publication in ApJ as one of the
first-look papers of the eDisk ALMA Large Progra
Impact of monopolar radiofrequency energy on subchondral bone viability
The purpose of this study was to analyze the impact of monopolar radiofrequency energy treatment on subchondral bone viability. The femoral grooves of six chinchilla bastard rabbits were exposed bilaterally to monopolar radiofrequency energy for 2, 4 and 8 s, creating a total of 36 defects. An intravital fluorescence bone-labeling technique characterized the process of subchondral bone mineralization within the 3 months following exposure to radiofrequency energy and was analyzed by widefield epifluorescence optical sectioning microscopy using an ApoTome. After 2 s of radiofrequency energy exposure, regular fluorescence staining of the subchondral bone was evident in all samples when compared to untreated areas. The depth of osteonecrosis after 4 and 8 s of radiofrequency energy treatment averaged 126 and 942 µm at 22 days (P < .05; P < .01). The 4 s treatment group showed no osteonecrosis after 44 days whereas the depth of osteonecrosis extended from 519 µm at 44 days (P < .01), to 281 µm at 66 days (P < .01) and to 133 µm at 88 days (P < .05) after 8 s of radiofrequency energy application. Though radiofrequency energy may induce transient osteonecrosis in the superficial zone of the subchondral bone, the results of this study suggest that post-arthroscopic osteonecrosis appears to be of only modest risk given the current clinical application in humans
A Survey of New Temperature-Sensitive, Embryonic-Lethal Mutations in C. elegans: 24 Alleles of Thirteen Genes
To study essential maternal gene requirements in the early C. elegans embryo, we have screened for temperature-sensitive, embryonic lethal mutations in an effort to bypass essential zygotic requirements for such genes during larval and adult germline development. With conditional alleles, multiple essential requirements can be examined by shifting at different times from the permissive temperature of 15°C to the restrictive temperature of 26°C. Here we describe 24 conditional mutations that affect 13 different loci and report the identity of the gene mutations responsible for the conditional lethality in 22 of the mutants. All but four are mis-sense mutations, with two mutations affecting splice sites, another creating an in-frame deletion, and one creating a premature stop codon. Almost all of the mis-sense mutations affect residues conserved in orthologs, and thus may be useful for engineering conditional mutations in other organisms. We find that 62% of the mutants display additional phenotypes when shifted to the restrictive temperature as L1 larvae, in addition to causing embryonic lethality after L4 upshifts. Remarkably, we also found that 13 out of the 24 mutations appear to be fast-acting, making them particularly useful for careful dissection of multiple essential requirements. Our findings highlight the value of C. elegans for identifying useful temperature-sensitive mutations in essential genes, and provide new insights into the requirements for some of the affected loci
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