Ronald Oswaldo Villamar Torres

Dr. Ronald Oswaldo Villamar Torres


Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 April 2019 in Chemosphere
Verified
Journal Article
Closed access
Naga Raju MaddelaNaga Raju Maddela
Naga Raju Maddela
BSBinbin Sheng
Binbin Sheng
SYShasha Yuan
Shasha Yuan
ZZZhongbo Zhou
Zhongbo Zhou
RTRonald Oswaldo Villamar Torres
Ronald Oswaldo Villamar Torres
FMFangang Meng
Fangang Meng

11 November 2022 in Fermentation
Verified
Journal Article
Open access
PDF file
GMGary Meza-Bone
Gary Meza-Bone
CMCarlos Meza-Bone
Carlos Meza-Bone
JAJuan Avellaneda-Cevallos
Juan Avellaneda-Cevallos
RCRonald Cabezas-Congo
Ronald Cabezas-Congo
RTRonald Oswaldo Villamar Torres
Ronald Oswaldo Villamar Torres
Marcos Barros-RodríguezMarcos Barros-Rodríguez
Marcos Barros-Rodríguez
The variability of climatic conditions throughout the year and the physiological maturity of plant material can have effects on the nutritional value of plants and the productive performance of animals. The aim was to determine the effect of three tropical forage species (Tithonia diversifolia, Erythrina poeppigiana and Cratylia argentea) harvested at four cutting ages (30, 45, 60 and 75 days), during the dry and rainy seasons on in vitro gas production, rumen pH, volatile fatty acids (VFA) and CH4 production. A completely randomized design in a factorial arrangement (three forage species, four cutting ages and two seasons) was used. Four Brahman bulls of 250.0 ± 20.5 kg of live weight were used, provided with a ruminal cannula for the extraction of ruminal fluid. The animals were kept separately in individual pens, where they were fed with P. maximum and water was provided ad libitum. Gas production among forage species was lower (p = 0.0001) in T. diversifolia and E. poeppigiana in the dry season. The cutting age had an influence on gas production, showing lower production (p = 0.0164) at 30 and 45 days in the dry season. The VFA production showed differences for the effect between forages in the rainy season, with higher values (p < 0.05) for acetic, propionic and butyric acid in the species E. poeppigiana, C. argéntea and T. diversifolia respectively. CH4 production showed differences between forage species, showing the lowest (p = 0.0001) production of CH4 in T. diversifolia for the dry and rainy seasons. It is concluded that the use of shrubby species (T. diversifolia, E. poeppigiana and C. argéntea) in ruminant production systems in the rainy and dry seasons, with an early regrowth age (30 and 45 days), present a promising alternative on the reduction of CH4.

14 January 2025 in Water
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Journal Article
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MAMaría Lorena Cadme Arévalo
María Lorena Cadme Arévalo
ACAndrade-Yucailla Verónica Cristina
Andrade-Yucailla Verónica Cristina
ALAlda Geijo Lopez
Alda Geijo Lopez
RTRonald Oswaldo Villamar Torres
Ronald Oswaldo Villamar Torres
CLCampisi Cadme Raisha Lorena
Campisi Cadme Raisha Lorena
Naga Raju MaddelaNaga Raju Maddela
Naga Raju Maddela
This study aimed to produce activated carbon from desilicated rice husks using various carbonization and activation methods, including a tube furnace, muffle furnace, and artisanal pyrolysis. The resulting activated carbons were characterized for their adsorptive capacity through the determination of iodine number and methylene blue adsorption; these are key indicators of specific surface area and adsorbent quality. Advanced characterization techniques were employed, such as scanning electron microscopy (SEM), which revealed a highly porous and irregular surface structure, and energy dispersive X-ray spectroscopy (EDS), confirming the effective removal of impurities and optimization of the elemental composition. Atomic force microscopy (AFM) demonstrated favorable surface roughness for adsorption processes. Among the samples, CaDH162-CADH53 exhibited the highest performance, with an iodine number of 1094.8 mg/g and a yield of 93.5%, signifying a high adsorption capacity. The activation treatments with phosphoric acid and calcium carbonate significantly improved the porous structure, further enhancing the material’s adsorptive properties. In conclusion, the activated carbons produced in this study demonstrated optimal physicochemical properties for water purification and contaminant treatment applications. These findings highlight the potential of using agricultural waste, such as rice husk, as a sustainable and scalable alternative for industrial-scale activated carbon production.

1 March 2020 in Bragantia
Verified
Journal Article
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SJSeyed Mehdi Jazayeri
Seyed Mehdi Jazayeri
RTRonald Oswaldo Villamar Torres
Ronald Oswaldo Villamar Torres
Cristian Gabriel Zambrano-VegaCristian Gabriel Zambrano-Vega
Cristian Gabriel Zambrano-Vega
LCLuz Cecilia García Cruzatty
Luz Cecilia García Cruzatty
Byron Wladimir Oviedo BayasByron Wladimir Oviedo Bayas
Byron Wladimir Oviedo Bayas
CVChristopher Viot
Christopher Viot
Three Gossypium species have been used to breed cotton as they vary in their fiber production and resistance to stresses. Transcription factors (TFs) mostly are present in different copies or isoforms by which they conduct their regulation. Their copy number can determine organism behavior to a cue. Simple sequence repeats (SSRs) are one of the most informative and versatile molecular markers. Transcription factors of three Gossypium species were compared in silico. Seventy eight percent of TFs were common between the three species. Single copy for each species were 6057 TF. Gossypium hirsutum and G. raimondii shared the most common interspecific TF. Gossypium arboreum species-specific TF were the least. MYB TF family with its subfamilies is the most abundant followed by bHLH and AP2/ERF family. Gossypium hirsutum generally possesses more TF copies compared to other two species. The 2109 single-copy clusters indicate that G. hirsutum has received one copy from only one parent. The five most abundant SSR markers of TF were dinucleotides AT, TA, TC, CT and TG belonging to G. raimondii. For G. arboreum and G. hirsutum they were trinucleotides CAA, CGA, TGA, GAA (CAT: G. hirsutum) and TCA. The findings suggest that there is regulatory difference between the three Gossypium species for fiber production and insect attack response. The differences may be due to some adaptive deletion events during speciation of G. hirsutum from its parents G. arboreum and

1 October 2021 in AGRIVITA Journal of Agricultural Science
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Journal Article
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JMJulio César Muñoz-Rengifo
Julio César Muñoz-Rengifo
JRJorge Alba Rojas
Jorge Alba Rojas
RTRonald Oswaldo Villamar Torres
Ronald Oswaldo Villamar Torres
JRJuan José Reyes-Pérez
Juan José Reyes-Pérez
SJSeyed Mehdi Jazayeri
Seyed Mehdi Jazayeri
The present research was aimed to evaluate the effectiveness of attractants placed in craft traps to reduce the bit population (Hypothenemus hampei). Three different mixtures of attractants and control were used in craft traps (4 treatments, which represent the mixtures frequently used by Amazonian coffee growers), arranged in a completely random blocks design. The variable number adult coffee drill was analyzed, as well as the most economical and effective treatment in the capture of adult coffee bit. The data were processed by means of a variance analysis to determine the differences between treatments, and the Tukey media multiple comparison test, at the statistical significance of p<0.05. The results have confirmed that the use of craft traps is a good alternative for adult coffee bit control. The treatment that allowed a greater capture of the coffee bits was T1 (mixture of 2 liters of boiled water + 200 grams of ground coffee), this was also the treatment that had the lowest cost for the elaboration of the artisan trap ($ 14.30). Finally, T1 turned out to be the most effective treatment for adult coffee drill capture in Amazonian conditions of Ecuador.

24 October 2021
Verified
Book Chapter
Closed access
PDF file
SJSeyed Mehdi Jazayeri
Seyed Mehdi Jazayeri
Byron Wladimir Oviedo BayasByron Wladimir Oviedo Bayas
Byron Wladimir Oviedo Bayas
RGRaquel Guerrero-Chuez
Raquel Guerrero-Chuez
YTYenny Torres-Navarrete
Yenny Torres-Navarrete
RTRonald Oswaldo Villamar Torres
Ronald Oswaldo Villamar Torres