ASSESSMENT OF THE EFFECT OF STABILIZATION WORKS AT THE RIVER CONFLUENCE DESAGUADERO -JACHJAHUIRA, BOLIVIA

MAURICIO ROMERO M.,MARCELO HEREDIA G. 한국수자원학회 2005 한국수자원학회 학술대회 Vol.2005 No.1

Identification of geometric parameters of a parallel robot by using a camera calibration technique

Mauricio Arredondo-Soto,Mario A. García-Murillo,J. Jesús Cervantes-Sánchez,Felipe J. Torres,Hector A. Moreno-Avalos 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.2

This work reports a novel method to estimate the geometrical parameters of a 2-(3-RRPS) parallel robot intended for manufacturing tasks. The method uses camera calibration techniques, and it is based on the concept of vertex space. The advantage of this technique is that the system does not require complex electronic instrumentation, and only uses a CCD camera as a main sensor and planar patterns, which makes it portable, accurate and low cost. To ensure the quality of the measurements, a methodology for characterization of the measurement system is included. The applicability and the advantages of using the proposed method are shown by means of the estimation of the geometrical dimensions of a spatial parallel manipulator with a relatively complex kinematic architecture. Experiments are conducted and show a significant improvement in manipulator accuracy when the parameters estimated with this technique are used.

Effect of Propionic Acid in the Germination of Rice Genotypes

Mauricio Marini Kopp,Viviane Kopp da Luz,Luciano Carlos da Maia,Rogério Oliveira de Sousa,Antonio Costa de Oliveira 한국작물학회 2008 Journal of crop science and biotechnology Vol.11 No.4

The objective of this work was to evaluate the germination of 12 rice genotypes under propionic acid stress, a phytotoxic compound produced in low drainage soils with high organic matter content. The tests were conducted with the first count of germination (PCG) and germination (G) of the genotypes subjected to 0, 3, 6, and 9 mM propionic acid concentrations. The seeds of each genotype were placed in germitest paper pre-soaked in treatment solutions forming individual bags. The germination was performed at 25 °C and the counts were carried out at 7 (PCG) and 14 days (G). A factorial random block design was performed with four replications of 50 seeds per genotype. Our study revealed that doses up to 9 mM propionic acid in the pre-soaking solution were efficient for genetic variability studies involving the character germination in rice; genetic variability for germination was detected in the collection of rice genotypes when subjected to propionic acid toxic effects. The genotypes Guichow, Dawn, and Toride-1 showed germination stability when subjected to increasing levels of propionic acid, and genotypes originated from irrigated system cultivation performed better when subjected to propionic acid stress. These three genotypes will be a good biological material to for enhance the resistance to phytotoxic compounds in rice. The objective of this work was to evaluate the germination of 12 rice genotypes under propionic acid stress, a phytotoxic compound produced in low drainage soils with high organic matter content. The tests were conducted with the first count of germination (PCG) and germination (G) of the genotypes subjected to 0, 3, 6, and 9 mM propionic acid concentrations. The seeds of each genotype were placed in germitest paper pre-soaked in treatment solutions forming individual bags. The germination was performed at 25 °C and the counts were carried out at 7 (PCG) and 14 days (G). A factorial random block design was performed with four replications of 50 seeds per genotype. Our study revealed that doses up to 9 mM propionic acid in the pre-soaking solution were efficient for genetic variability studies involving the character germination in rice; genetic variability for germination was detected in the collection of rice genotypes when subjected to propionic acid toxic effects. The genotypes Guichow, Dawn, and Toride-1 showed germination stability when subjected to increasing levels of propionic acid, and genotypes originated from irrigated system cultivation performed better when subjected to propionic acid stress. These three genotypes will be a good biological material to for enhance the resistance to phytotoxic compounds in rice.

The Neighborly Relations between Middle Eastern Migrants and Indigenous People in Patagonia

Mauricio Dimant 한국라틴아메리카학회 2017 라틴아메리카연구 Vol.30 No.1

In February of 1910 the Argentine press reported the disappearance of dozens of Middle Eastern immigrants in Patagonia. According to the police department in charge of the investigation, at least several of the missing immigrants of Arab origin had been killed and eaten by local groups of indigenous people. Immigrants from the Middle East, who were vulnerable as newcomers to the region, did not respond to the crisis of murder and cannibalism as “Arabs” or as Argentineans, but as Patagonians. This kind of public behavior opens a window not only to the importance of local identities at the subnational level in Argentina, but also the role of local and negative experiences in the integration of immigrants and ethnic minorities. This article explores the complexities of the interaction between immigrants from the Middle East and the indigenous population in Patagonia in order to rethink the local experience of ethnic-migrant minorities in Argentina. It argues that Argentine identity of Arabic-speaking immigrants in Patagonia emerged mainly as a result of shared local or regional interests rather than merely through an attachment to the federal state.

Modeling and identification of a class of MR fluid foam dampers

Mauricio Zapateiro,Ningsu Luo,Ellen Taylor,Shirley J. Dyke 국제구조공학회 2010 Smart Structures and Systems, An International Jou Vol.6 No.2

This paper presents the results of a series of experiments conducted to model a magnetorheological damper operated in shear mode. The prototype MR damper consists of two parallel steel plates; a paddle covered with an MR fluid coated foam is placed between the plates. The force is generated when the paddle is in motion and the MR fluid is reached by the magnetic field of the coil in one end of the device. Two approaches were considered in this experiment: a parametric approach based on the Bingham, Bouc-Wen and Hyperbolic Tangent models and a non parametric approach based on a Neural Network model. The accuracy to reproduce the MR damper behavior is compared as well as some aspects related to performance are discussed.

Isolation and Molecular Characterization of Xylella fastidiosa from Coffee Plants in Costa Rica

Mauricio Montero-Astua,Carlos Chacon-Diaz,Estela Aguilar,Carlos Mario Rodriguez,Laura Garita,William Villalobos,Lisela Moreira,John S. Hartung,Carmen Rivera 한국미생물학회 2008 The journal of microbiology Vol.46 No.5

Coffee plants exhibiting a range of symptoms including mild to severe curling of leaf margins, chlorosis and deformation of leaves, stunting of plants, shortening of internodes, and dieback of branches have been reported since 1995 in several regions of Costa Rica’s Central Valley. The symptoms are referred to by coffee producers in Costa Rica as “crespera” disease and have been associated with the presence of the bacterium Xylella fastidiosa. Coffee plants determined to be infected by the bacterium by enzyme linked immunosorbent assay (ELISA), were used for both transmission electron microscopy (TEM) and for isolation of the bacterium in PW broth or agar. Petioles examined by TEM contained rod-shaped bacteria inside the xylem vessels. The bacteria measured 0.3 to 0.5 μm in width and 1.5 to 3.0 μm in length, and had rippled cell walls 10 to 40 nm in thickness, typical of X. fastidiosa. Small, circular, dome-shaped colonies were observed 7 to 26 days after plating of plant extracts on PW agar. The colonies were comprised of Gram-negative rods of variable length and a characteristic slight longitudinal bending. TEM of the isolated bacteria showed characteristic rippled cell walls, similar to those observed in plant tissue. ELISA and PCR with specific primer pairs 272-1-int/272-2-int and RST31/RST33 confirmed the identity of the isolated bacteria as X. fastidiosa. RFLP analysis of the amplification products revealed diversity within X. fastidiosa strains from Costa Rica and suggest closer genetic proximity to strains from the United States of America than to other coffee or citrus strains from Brazil.

Seed Oil Ethoxylate Adjuvants and Their Influence on Retention and Rainfastness of the Contact Fungicide Mancozeb

Mauricio Hunsche,Michaela Schmitz-Eiberger,Georg Noga 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-

Impact of Cyclodextrins on Postprandial Glycemia: Evaluation in Experimental Animal Model Using the Real-Time Continuous Glucose Monitoring System

Mauricio Fumio Sybuia,Ma´rcio Guilhermetti,Camila Sampaio Mangolim,Roberto Barbosa Bazotte,Graciette Matioli 한국식품영양과학회 2015 Journal of medicinal food Vol.18 No.6

The impact of cyclodextrins (CDs) on postprandial glycemic response employing the real-time continuous glucose monitoring system (RT-CGMS) was investigated. For this purpose, α-CD, β-CD, γ-CD, HP-β-CD, curdlan, and dextrin at doses of 10 and 100 mg/kg were orally administered in rats. The RT-CGMS was efficient to evaluate the impact of CDs on postprandial glycemia. The results showed that α-CD, β-CD, dextrin, and curdlan did not reduce the glycemic response after the administration of starch. In contrast, the HP-β-CD (100 mg/kg) attenuated the rise in glycemia. Moreover, the γ-CD blunts the postprandial glycemic excursion at doses of 10 and 100 mg/kg. Therefore, γ-CD could attenuate the rise in glycemia promoted by oral administration of starch. Considering that the treatment of postprandial hyperglycemia is necessary to prevent type 2 diabetes, this study opens the perspective of better control of postprandial glycemia by the addition of γ-CD in food.

Acute Colonic Volvulus in a Mexican Population: A Case Series

Mauricio Gonzalez-Urquijo,Mario Rodarte-Shade,Gerardo Gil-Galindo 대한대장항문학회 2020 Annals of Coloproctolgy Vol.36 No.1

Purpose: Colonic volvulus constitutes a significant cause of large bowel obstruction in adults. Most studies of colonic volvulus come from high endemic zones and are limited by the small number of patients. In our region, there is a shortage of studies concerning this disorder, and treatment of colonic volvulus remains controversial. Methods: This is a retrospective study of 34 patients who presented with colonic volvulus at a single academic institution in a 4-year period and their respective treatment and outcomes. Results: A total of 34 patients, 17 males (50%) and 17 females (50%), with a mean age of 55 ± 23.9 years underwent treatment for colonic volvulus. Twelve patients (35.3%) underwent initial decompression, followed by a Hartman procedure in 4 patients (11.7%) and sigmoid resection with primary anastomosis in 3 patients (8.8%), with 3 fatalities (8.8%) following initial decompression. Two patients (5.8%) were lost to follow-up. Twenty-two patients (64.7%) underwent emergency surgery, of whom 16 (47%) underwent a Hartman procedure, with colorectal anastomosis in 9 patients (26.4%), with 3 fatalities (8.8%) immediately after the first procedure. Four patients (11.7%) were lost to follow up after the Hartman procedure. Of the 6 remaining patients (17.6%), of the emergency surgical group, 3 patients (8.8%) had an initial sigmoidectomy and primary anastomosis, and the remaining 3 patients (8.8%) had a cecal volvulus with a right hemicolectomy performed with primary anastomosis in 2 patients (5.8%) and with a fatality in the remaining patient, on whom a terminal ileostomy was performed for damage control. The mean hospital stay was 5.7 days, with an overall mortality rate of 23.5%. Conclusion: Acute colonic volvulus in our region is not as uncommon as in other parts of the world. This disorder must be suspected when a patient presents with abdominal pain, abdominal distension, and bean sign on plain X-rays and/or a whirl sign on computed tomography scan.

Community response to urban noise in public spaces at Rio de Janeiro City, Brazil

Mauricio Pereira 한국소음진동공학회 2003 한국소음진동공학회 국제학술대회논문집 Vol.2003 No.8