bluuebunny/crossref_metadata_2025 huggingface dataset:
Maize seedling performance as a potential index for drought tolerance
Authors: Kravic Natalija , Hadzi-Taskovic Sukalovic , Babic Vojka , Srdic Jelena , Mesarovic Jelena , Andjelkovic Violeta
Published: October 2017

Twenty-six maize landraces were tested in order to evaluate maize seedling performance as an index for drought tolerance in adult plants. Samples were subjected to polyethylene glycol-induced osmotic stress at the early seedling stage. Grain yield was obtained in field experiments under well-watered (OC) and a combination of drought and high plant density (HD) conditions. Osmotic stress caused a reduction in seedling growth (length, fresh and dry weight), and increase in the shoot and in particular the root proline contents in the majority of landraces, and variations in root peroxidase (POD) activity. Genotypes displaying more pronounced root growth reduction and higher proline contents exhibited decreased POD activity under osmotic stress. Direct positive correlations between the proline content and growth inhibition, and between the proline and soluble protein content were established. Correlations between the changes in POD activity and growth parameters were significant and positive, and significant but negative with the changes in the proline content. In the field, water stress led to a reduction in grain yield in all of the tested landraces. Correlations between grain yield from both experimental sets (OC and HD) and osmotic-induced changes in seedling root growth were negative, which was opposite to the highly significant and positive correlations between the changes in the seedling root proline content and yield. Also, genotypes with the highest seedling root proline content increase under osmotic stress, exhibited the highest stress tolerance index (STI) based on grain yield achieved under both field conditions. Our results indicate that lower changes in POD activity and especially an increased proline content after exposure to osmotic stress during the early seedling stage could be considered as useful indices to facilitate selection efficiency for drought tolerance in adult plants.
The effects of β-lactam antibiotics and hygromycin B on de novo shoot organogenesis in apple cv. Golden Delicious
Authors: Stanisic Mariana , Ninkovic Slavica , Savic Jelena , Cosic Tatjana , Mitic Nevena
Published: October 2017

Since the genetic transformation of the apple is strongly genotype-dependent and generally inefficient, the evaluation of factors affecting shoot regeneration are crucial for the establishment of a successful transformation process. In this report, we evaluated the effects of the ?-lactam antibiotics meropenem and timentin on in vitro regeneration via de novo shoot organogenesis from leaf explants of apple cv. Golden Delicious, as well as on the growth of the Agrobacterium tumefaciens strain EHA 105, and compared them with the commonly used ?-lactam cefotaxime. Also, we report for the first time the effect of hygromycin B as a selective agent in the domesticated apple, as regards shoot regeneration and shoot multiplication efficiency. We observed that cefotaxime and timentin at concentrations higher than 100 mg L-1 were sufficient to prevent Agrobacterium growth during a two-week period, while meropenem exhibited an inhibitory effect on bacterial growth at all tested concentrations (25-150 mg L-1). Cefotaxime at a concentration of 300 mg L-1 increased the number of regenerated shoots per explant (9.39) in comparison with the control (7.67). In contrast to cefotaxime, meropenem and timentin caused a decrease in shoot regeneration efficiency, but larger and more developed shoots were obtained on meropenem (25-125 mg L-1) after the same period of cultivation. Hygromycin B at a concentration of 5 mg L-1 or higher completely inhibited shoot regeneration and induced explant tissue necrosis. Therefore, the selection procedure with a final concentration of 4 mg L-1 throughout organogenesis and 10 mg L-1 for further shoot growth and multiplication is recommended for an efficient transformation process in apple cv. Golden Delicious.
Stress Distribution, Tooth Remaining Strain, and Fracture Resistance of Endodontically Treated Molars Restored Without or With One or Two Fiberglass Posts And Direct Composite Resin
Authors: Barcelos LM , Bicalho AA , Veríssimo C , Rodrigues MP , Soares CJ
Published: October 2017

Objectives:

To evaluate the effects of direct composite resin without a post or with one or two fiberglass posts on the restoration of severely compromised endodontically treated molars.

Methods and Materials:

Forty-five molars with 2 mm of “remaining tooth structure” were divided into three groups: Wfgp, restored with Filtek Z350XT without a fiberglass post; 1fgp, restored with Z350XT with one fiberglass post in the distal root canal; and 2fgp, restored with Z350XT with two fiberglass posts, one in the distal root canal and the other in the mesial-buccal root canal. The teeth were load cycled. Tooth remaining strain was measured using strain gauges (n=10) at two moments: TrSt-100 N, during 100 N occlusal loading, and TrSt-Fr, at fracture load. Fracture resistance was calculated, and fracture mode was classified. The elastic modulus and Vickers hardness were calculated using dynamic indentation (n=5). Stress distribution was analyzed by three-dimensional finite element analysis.

Results:

The use of two fiberglass posts resulted in lower fracture resistance than was noted in the groups with one fiberglass post and without fiberglass posts. The lingual surface of the remaining tooth had higher strain values than the buccal surface, regardless of the restorative technique and moment of evaluation. The absence of a fiberglass post resulted in significantly higher strain values and more irreparable fracture modes than were noted in the other groups. The use of one fiberglass post had a better strain/fracture resistance ratio. Stresses were concentrated in the occlusal portion of the post and in the furcation region. The presence of one fiberglass post resulted in better stress distribution in the entire distal root dentin, reducing stress on the critical areas.

Conclusions:

The use of one fiberglass post for restoring molars with direct composite resin resulted in higher fracture resistance than did the use of two fiberglass posts; it also resulted in better tooth remaining strain and stress distribution and more reparable fracture modes than were seen in the group without a fiberglass post.
Effect of Oxygen Inhibition Layer of Universal Adhesives on Enamel Bond Fatigue Durability and Interfacial Characteristics With Different Etching Modes
Authors: Ouchi H , Tsujimoto A , Nojiri K , Hirai K , Takamizawa T , Barkmeier WW , Latta MA , Miyazaki M
Published: October 2017

Objective:

The purpose of this study was to evaluate the effect of the oxygen inhibition layer of universal adhesive on enamel bond fatigue durability and interfacial characteristics with different etching modes.

Methods:

The three universal adhesives used were Scotchbond Universal Adhesive (3M ESPE, St Paul, MN, USA), Adhese Universal (Ivoclar Vivadent, Schaan, Lichtenstein), and G-Premio Bond (GC, Tokyo, Japan). The initial shear bond strength and shear fatigue strength to enamel was determined in the presence and absence of the oxygen inhibition layer, with and without phosphoric acid pre-etching. The water contact angle was also measured in all groups using the sessile drop method.

Results:

The enamel bonding specimens with an oxygen inhibition layer showed significantly higher (p<0.05) initial shear bond strengths and shear fatigue strengths than those without, regardless of the adhesive type and etching mode. Moreover, the water contact angles on the specimens with an oxygen inhibition layer were significantly lower (p<0.05) than on those without, regardless of etching mode.

Conclusion:

The results of this study suggest that the oxygen inhibition layer of universal adhesives significantly increases the enamel bond fatigue durability and greatly changes interfacial characteristics, suggesting that the bond fatigue durability and interfacial characteristics of these adhesives strongly rely on its presence.
Caracterización fisicoquímica del suero dulce obtenido de la producción de queso casero en el municipio de Pasto.
Authors: Alava Viteri Clemencia , Gómez de Illera Margarita , Maya Pantoja Jorge Aníbal
Published: October 2017

La industria láctea en el municipio de Pasto se cataloga como polo de desarrollo local, con posibilidades de consolidarse en uno de los ejes estratégicos dentro del marco de Nariño productivo y competitivo.La producción de un tipo de queso fresco, denominado casero, que trae consigo la producción de suero; puede considerarse como un problema ambiental debido a la descarga de este producto al medio ambiente.El suero obtenido de la fabricación de queso fresco es factible de utilizarse en la elaboración de nuevos productos y la caracterización fisicoquímica del suero que se produce en el municipio de Pasto, procedente del queso casero, contribuye a plantear opciones de industrialización del mismo y evitar que sea desechado de manera inadecuada. Los parámetros que se determinaron fueron acidez, pH, grasa, densidad, lactosa, proteína y sólidos totales. Para ello se tomaron tres plantas dedicadas al procesamiento de queso fresco tipo casero, ubicadas en el municipio de Pasto.Los resultados promedios de las muestras analizadas arrojaron que el suero es dulce, con un pH promedio de 6.52, valores de acidez en promedio de 0.08% de ácido láctico; destacándose los contenidos de proteína con 1.2% y grasa con 0.42% en promedio. En cuanto a la lactosa, se encontró por debajo de lo establecido en la resolución 02310 de 1986 del Ministerio de Salud de Colombia, en lo que tiene que ver con los componentes fisicoquímicos de suero líquido.
Efecto de la roca fosfórica parcialmente acidulada y calcinada en la producción de maíz
Authors: Torrente Trujillo Armando
Published: October 2017

Se evaluó el efecto de la roca fosfórica (RF) de la mina Media Luna - Huila y los productos de los procesos de acidulación y calcinación, como fuentes de fósforo aprovechable sobre la producción de maíz variedad ICA V-305, y su asimilación en el sistema suelo-planta. Las unidades experimentales se constituyeron con mezcla de suelo arenoso franco, 15% compost de porquinaza y 10% de cascarilla de arroz, distribuidas en tratamientos así: T1 - sin fósforo, T2 - 100 g/planta de Fosforita- 30P, T3 - 100 g/planta de RF parcialmente acidulada malla 20, T4 - 100 g/planta de RF parcialmente acidulada malla 100, T5 - 100 g/planta de RF calcinada, T6 - 100 g/planta de RF calcinada con serpentina y T7 - 100 g/planta de DAP. Se aplicó un diseño experimental completamente al azar con 7 tratamientos y 9 repeticiones cuyas variables de respuesta fueron: rendimiento de materia seca (MS), altura de plantas (AP), diámetro medio de tallo (DT), contenido de fósforo en tejido foliar de maíz (CFM) y contenido de fósforo en el suelo (CFS). Las mejores características morfológicas y desarrollo vegetativo en maíz, se presentaron con Fosforita-30P y RF parcialmente acidulada, los mayores rendimientos en cosecha se dieron con RF parcialmente acidulada malla 100 y DAP con promedio de 7.8 ton/ha y sin diferencias significativas al 5%. Se observaron rendimientos menores y diferencias significativas con aplicación de Fosforita 30P, roca fosfórica calcinada y el testigo.
Cambio climático y agrobiodiversidad
Authors: Cardozo Conde Carlos Iván
Published: October 2017

Uno de los principales retos de la humanidad es garantizar la seguridad alimentaria global. Desde los años 60 ́s se han venido realizando esfuerzos por aumentar la producción de alimentos para una población creciente. Los programas de mejoramiento juegan un papel importante, al igual que las comunidades de medianos y pequeños agricultores quienes conservan un alto porcentaje de la variabilidad genética de los principales cultivos mediante sistemas locales de producción. Nuevas tecnologías se han incorporado, como la biotecnología, la agricultura eco-eficiente, la agricultura inteligente, con el fin de desarrollar sistemas productivos sostenibles. Si bien, el suministro de alimentos se ha incrementado, los fenómenos del Calentamiento Global -CG y el Cambio climático -CC aparecen como una amenaza, pues sus efectos sobre aspectos fenológicos y fisiológicos de los cultivos, estimados mediante modelación, pronostican una fuerte reducción en la biodiversidad y en los rendimientos de los cultivos a nivel mundial, con variaciones según las regiones. En este sentido, es necesario iniciar planes de adaptación oportunos y acordes con los niveles de vulnerabilidad según los diferentes países. Ante esta situación, una estrategia para adaptarse a los escenarios futuros que plantea el Calentamiento Global, es incorporar la mayor biodiversidad posible y disponible en programas de mejoramiento. En este contexto se requiere de gran creatividad, para no solo mantener sino aumentar los rendimientos de los cultivos y mitigar la pérdida de recursos naturales con el fin de garantizar la seguridad alimentaria mundial.
Hydration kinetics of four quinoa (Chenopodium quinoa Willd.) varieties
Authors: Pumacahua Ramos Augusto , Limaylla Guerrero Katherine Milusca , Telis Romero Javier , Lopes Filho Jose Francisco
Published: October 2017

The effect of time, temperature and varieties were analyzed during kinetics hydration of quinoa grains and some physical properties were determined. Quinoa grain varieties Kancolla, Salcedo Inia, Blanca de Juli and Pasankalla were used in the study. The hydration was performed in triplicate with 25 g of grain immersed into a solution with 0.55% lactic acid and 0.2% SO2, three temperatures (30, 40 and 50
Respuesta del ají (Capsicum annuum L. Var. Cayena) a concentraciones de N, P, K, Ca y Mg en Palmira, Valle Del Cauca, Colombia
Authors: Mejìa de Tafur Marìa Sara , Martínez Marulanda Adriana Carolina , Ibarra Espinosa Dora Mònica , García Dávila Mario Augusto , Cayon Salinas Daniel Gerardo
Published: October 2017

En la Universidad Nacional de Colombia, Sede Palmira, se estableció un experimento para determinar los requerimientos nutricionales (N, P, K, Ca y Mg) del ají Capsicum Annuum L., con 16 tratamientos (soluciones nutritivas), cuatro repeticiones, y cinco muestreos a los 20, 40, 70, 100 y 140 días después del trasplante. Los semilleros se establecieron en paneles con arena de río esterilizada, las plántulas fueron regadas con las soluciones nutritivas correspondientes a cada tratamiento y trasplantadas 20 días después de la siembra (dds) amacetas de 6 Kg de capacidad, se empleó arena de cuarzo como sustrato. Se tomó como referencia la solución de Hoagland y Arnon; los demás tratamientos se obtuvieron variando las concentraciones de N, P, K, Ca, y Mg. La concentración alta correspondió a la del testigo más 50% de la misma; la media, el 25% de la concentración alta y la baja, un cuarto de la concentración media. El nivel crítico de los elementos nutritivos se determinó mediante la construcción de curvas de calibración, relacionando la concentración de cada uno de ellos con la producción de biomasa. Se trazó una línea paralela al eje de las X, tomado como referencia el 95% de la biomasa máxima. Los puntos que cortan la curva de respuesta corresponden al nivel crítico o rango de concentración adecuada de cada elemento nutritivo. Los rangos de concentración adecuados en la solución nutritiva para el ají variedad cayena son: N 16,2 - 21,5 mmol.L-1. P 1,1 – 1,4 mmol.L-1, K 4,4 – 8,2 mmol.L-1. No se encontraron los requerimientos para Ca y Mg.
Impacto del fenómeno MOOC: la personalización en la educación superior / MOOC phenomenon impact: Personalization in higher education
Authors: Escudero Nahón Alexandro , Núñez Urbina Alicia Angélica
Published: October 2017

Desde su aparición en 2008, los cursos en línea masivos y abiertos (MOOC, por sus siglas en inglés) llegaron a ser catalogados como un fenómeno con alto impacto en la educación universitaria; sin embargo, a través de los años se ha hecho evidente que la concepción inicial de estos ha sufrido transformaciones. Los MOOC se encuentran en plena evolución y su creciente diversificación muestra un alejamiento de la noción de masivo. Este trabajo presenta resultados preliminares de una investigación en curso, basada en la Metodología de la Teoría Fundamentada. A partir del análisis de datos cualitativos, fue posible identificar las categorías de un MOOC personalizable y cómo se ha reflejado este concepto en la educación superior, desde la experiencia y perspectiva de usuarios que ya han sido consumidores y/o productores de este tipo de cursos. Los datos sugieren que, los usuarios de MOOC experimentan cuatro fases: Consumo indiscriminado, Discriminación inteligente, Tropicalización y Personalización. En instituciones de educación superior, los MOOC están siendo utilizados como estrategia para resolver problemas específicos: semestre cero, complemento a clases presenciales, divulgación, entre otros. La diversificación que están sufriendo los MOOC pone en evidencia la necesidad de un alejamiento de la noción de masivo. Pensar en proponer metodologías para el diseño de MOOC que vayan de lo masivo a lo personalizable facilitará la producción de MOOC para atender necesidades de grupos de usuarios específicos en contextos educativos con objetivos particulares.
Consumer Online Brand Trust and Determinants in Qatar
Authors: Bhuian Shahid Nakib
Published: October 2017

The paper theorizes and examines consumer online brand trust (COBT) and its salient determinants in Qatar in the Gulf Cooperation Council (GCC) region. Results from a sample of 178 respondents in Qatar indicate consumer online brand familiarity, consumer satisfaction with the online brand and website, word-of-mouth communications between online consumers and information on the online brand are positively related to COBT, whilst web design of the brand's website and is not. The theoretical and practical implications are discussed.
How do Human Capital Planning and Employee Development Relate with Employee Retention in High Educational Institutions in Sokoto State?
Authors: Abboh Abdullahi Umar
Published: October 2017

Human capital planning is one area that has witnessed spurred development lately. Organizations regardless of motive are getting more flat and relaxed by moving far away from the known hierarchical systems. The central theme of human capital planning (HCP) is to work out modalities that will favor both the employer and employee. This paper used academic staff in higher educational institutions (HEI's) and examined the relationship among HCP, employee development and employee retention. The views of 416 respondents were analyzed using SmartPLS 2.0. It was revealed that two out of the three hypotheses were proven and there were no enough evidence to support one. The paper recommends that employee development should be revisited and accorded a requisite modification that will serve as a morale booster and more or less a retention strategy in HEI's in Sokoto State, Nigeria.
The differences of tooth density changes in the applications of 45% carbamide peroxide PF and 38% hydrogen peroxide PF as dental bleaching agents and after the application of 1.2% acidulated phosphoric fluoride
Authors: Jurnalis Devriza , Natasasmita Setiawan , Sukartini Endang
Published: October 2017

The changes of tooth density is caused by the dissolutions of mineral enamel (demineralization) by bleaching agent. The purpose of this research was intended to know tooth density changes after the application of bleaching agent using 45% carbamide peroxide potassium fluoride (PF) and 38% hydrogen peroxide potassium fluoride (PF) and after the application of 1.2% acidulated phosphoric fluoride (APF).This research was true experimental in-vitro. Sample taking was by random sampling. The sample consisted of 32 maxillary central incisive permanent teeth. The tooth density was measured using RVG (Radiovisiography). The research results were analyzed and tested in a pair and in a pair of two sample for means using t student method. The conclusion of the research was a decrease of tooth density after the application of bleaching agent with 45% carbamide peroxide PF and 38% hydrogen peroxide PF with statistically significant. After the application of 1.2% APF the density increased significantly but the density was lower than original density. There was no significant difference between bleached with 45% carbamide peroxide potassium fluoride and 38% hydrogen peroxide potassium fluoride.
Composition, tensile strength, and elastic modulus of Orden as cast post alloy
Authors: Anggraini Novi , Hasratiningsih Zulia , Subrata Gantini
Published: October 2017

Post is one element of the fixed restorations that is generally used to restore endodontically treated teeth at Prosthodontic Installation of Oral and Dental Hospital (RSGM) Faculty of Dentistry Universitas Padjadjaran, whereas Orden alloy is still used as cast post material. The faculty supplies Orden without packaging or manuals, so the information about its composition and mechanical properties are not available. This study was conducted to search the composition, tensile strength, and elastic modulus of Orden. For the composition test, a specimen with size 20x20x2 mm3 was tested with Optical Emission Spectroscopy (OES). For tensile test, 6 specimens were made according to ASTM Standard E8. While for bending test, 6 specimens were made according to ASTM Standard E855. The Universal Testing Machine Instron 1195 was used to test the tensile strength and elastic modulus. The value of tensile strength of Orden was compared to gold alloy type III and the value of elastic modulus of Orden was compared to dentin. Composition test found that Orden was a brass with the largest ingredient of copper 53.76 wt%, followed by zinc 44.94 wt%, and aluminum 1.17 wt%. The statistic calculation showed that tensile strength of Orden was lower than gold alloy type III and the elastic modulus of Orden was higher than dentin.
Standard mandibular canine index of the Malaysian Indian student used for sex prediction in forensic dentistry
Authors: Ren Beh Wee , Ardan Rachman , Rikmasari Rasmi
Published: October 2017

Identification of the unknown body is a medical, legal and humane responsibility of the forensic team to evaluate data relevant to the identification. The purpose of this research was to obtain necessary data to compute and analyze the Mandibular Canine Index (MCI) between Malaysian Indian males and females studying in Universitas Padjadjaran as well as to determine the Standard Mandibular Canine Index (Standard MCI) for the Malaysian Indian community. This research used a descriptive and analytical survey approach and was done though a stratified random proportional sampling technique. The result of this research established a statistical significant difference between males and females Mandibular Canine Index (MCI) with the level of confidence of 95% with the mean of males as 0.260±0.019 and females as 0.236±0.012. The Standard Mandibular Canine Index of the Malaysian Indian community was 0.248. The overall success to predict the sex using this Standard Mandibular Canine Index was 76.67%. It was concluded that Standard Mandibular Canine Index could be used for sex prediction as a supporting technique.
Anti-tumor agent celecoxib activity towards SP-C1 tongue cancer cells invasion (in vitro)
Authors: Achmad Harun , Satari Mieke Hemiawati , Oewen Roosje Rosita , Supriatno S.
Published: October 2017

Invasion is a characteristic of the occurrence of cancer and indicates the cancer cells' capability to destroy and degrade the border between the epithet and basal membrane to further spread into the surrounding extra-cellular matrix. The purpose of this research was to find the existence of impediment at the SP-C1 tongue cancer cell using celecoxib chemopreventive medication. The SP-C1 tongue cancer cells were treated in vitro using celecoxib medication as a research subject at the following concentrations 5, 10, 25, 50, 75, 100, 125%; and 0 as control group (only DMEM growth medium treatment). Pure experimental testing was carried out for 24 and 48 hours, with observation and calculation of an average number of SP-C1 tongue cancer cells. The data collected were analyzed using the ANOVA test with Newman Keuls paired range test or t-test. Research results indicated that the average number of SP-C1 tongue cancer cells invasion after administration of celecoxib medication based on administration concentration and time statistically yielded significant results. The ANOVA test results were statistically significant, that is, average occurrence of the number of SP-C1 tongue cancer cells due to the use of celecoxib at certain concentrations compared to that without celecoxib was different. At celecoxib of zero (control) concentration was 24.4 with celecoxib concentration starting at 5 up to 125% experienced a decline from its average 11 to become 2.3. The conclusion of the research was that the greater the celecoxib concentration administered, the greater the effect on the impediment of SP-C1 tongue cancer cell invasion.
Rat dental pulp tissue reaction after capped with propolis derived nonflavonoid extract
Authors: Sabir Ardo
Published: October 2017

Propolis is a resinous material collected by honey bees from various plants. Many types of research have shown that it has antibacterial and anti-inflammation activities. Flavonoid is the main chemical substance in propolis that inhibits bacterial growth and reduces the release of free radicals, suggesting that this component has anti-bacterial and anti-inflammatory properties. However, there is another chemical substance in propolis that shows antibacterial dan anti-inflammatory activities. The purpose of the present study was to assess the rat dental pulp tissue reaction after capped with propolis derived non-flavonoids extract. Non-flavonoids substances were purified from an ethanol extract of propolis obtained from South Sulawesi, Indonesia. A Class I cavity was prepared on the occlusal surface of the right maxillary first molar in Spraque-Dawley rats. The dental pulp was exposed and then capped with a zinc oxide-based filler as a control (Group I), or non-flavonoids propolis (Group II). Then, each cavity was filled with glass ionomer cement. The animals were sacrificed at week 1, 2, or 4. Biopsy samples were obtained, and these were stained and viewed by light microscopy. The histological examination was based on the presence of polymorph nuclear leukocytes and macrophages. The results showed that pulp inflammation occurred in both groups as early as week 1. However, the inflammation occurred in Group II was relatively milder compared to Group I at all time period. Therefore, present results suggest that application of non-flavonoids propolis extract on rat's dental pulp tissue might inhibit inflammatory process.
The difference nanocomposite hardness level using LED photoactivation based on curing period variations
Authors: Tatian Hasiana , Fadil Moch. Richata , Armilia Milly
Published: October 2017

Polimerizatian is the critical stage to determine the quality of composites resin, this involves isolated monomer carbon double bonds being converted to an extended network of single bonds. Physical and mechanical properties of composites are influenced by the level of conversion attained during polymerization. An adequate light intensity and light curing time are important to obtain the degree of polymerization. The objective of this study is to evaluate the difference of the hardness nanocomposites which activated by LED LCU based on the variation of curing times. This study is a true experimental research. The samples were made from nanocomposites material with cylinder form of 4 mm in depth, 6 mm in diameter. This samples divided into 3 groups of curing times. Group, I was cured for 20's curing time as a control due to manufactory recommended; Group II was cured for 30's, and Group III was cured for 40's and the hardness (Rebound hardness tester) was determined using Rebound scale (RS) and converted by Mohs scale (MS). There was a very significant level of hardness rate from each group using ANOVA test. The result of the study concludes that there were the differences on the nanocomposites hardness level cured under different curing times 20, 30 and 40 sec. The longer of curing times, the higher level of hardness.
Producción Más Limpia: una revisión de aspectos generales
Authors: Bernal Figueroa Andrea Angélica , Beltrán Parada Claudia Johana , Márquez Márquez Andrés Felipe
Published: October 2017

Este artículo presenta una revisión de aspectos básicos de la Producción Más Limpia (PML) como estrategia ambiental preventiva, la cual se integra a los procesos productivos con el fin de hacerlos más eficientes ambientalmente en cuanto a la utilización de recursos y materias primas, entre otros. Se mencionan aspectos generales en cuanto al impacto ambiental en Colombia enfocado en los sistemas productivos, origen y evolución general del concepto, así como definición, aspectos generales, beneficios y dificultades para su implementación. De manera general, se concluye que la PML es una estrategia que puede contribuir en la disminución del impacto ambiental generado por los diferentes sistemas productivos; sin embargo, es necesario realizar actividades que permitan impulsar su difusión y conocimiento por parte de los diferentes actores involucrados, así como resaltar los beneficios sociales, ambientales y económicos que su aplicación podría generar. Palabras clave: impacto ambiental, producción más limpia, sistemas productivos, sistemas de gestión ambiental.
Assessing the relationship between Vocabulary Level Test (VLT) and reading comprehension
Authors: Susanto Alpino
Published: October 2017

It has been considered crucial about how vocabulary knowledge in relation with reading comprehension. This research was conducted to explore the link of Indonesian students Vocabulary Level Test (VLT) performance and their reading textbook on reading subject. Through this pilot research, it can describe the implications profile in English teaching process especially in reading. Furthermore it can give more information in how to measure the reading textbook reference for reading subject or other similar subject that involve reading activities. There were 30 undergraduate students in Universitas Putera Batam that participated in the VLT. Their English textbook (Mosaic 1) was profiled to measure the lexical vocabulary level. The results indicated that only 1% of the participants had mastered the 2000-word level which means the vocabulary textbook-level is still far from students vocabulary knowledge. From the level of comparison theoretically they would have difficulties to comprehend the reading textbook, and some additional activities would be recommended, before, during and after the reading subject.
The functions of code switching in an English language classroom
Authors: Fachriyah Eva
Published: October 2017

The aims of this research is to gain a deep understanding and to knowing  the use of code-switching that have done by students and lecturers in interaction when teaching learning in English class. Specifically or as sub-focus in this research was aimed to determine the functions for the use of code switching that is used by both  of the speaker and hearer that in this case the interaction between lecturer and students when learning takes place. This research was conducted at the campus of the State Islamic Institute "Sultan Maulana Hasanuddin Banten" at the Faculty of Education and Teaching in English department at the third semester. This study was a qualitative research by using ethnography of communication method. The techniques and procedures of data collection were used such as observation, recordings and transcripts, and interviews. Based on data analysis, the use of code switching in English classroom has got the result for functions of code switching in interaction when the learning take place. Key words: code switching, English learning, ethnography communication.
EFL reading comprehension and reading strategies of different genders
Authors: Islamiah Neneng , Aprizani Yudha , Perdana Iwan
Published: October 2017

Two of the most examined dimension of reading strategies that have an affective influence on different genders are cognitive strategy and metacognitive strategy. This study was aimed to find out whether reading comprehension using different strategies would have different result or not for the two different genders. The researchers used a quantitative causal-comparative research approach, and data were collected from two instruments: reading comprehension test and questionnaires. A number of 50 students (25 females and 25 males) from one of the universities in Banjarmasin participated in this study. The results showed that between the two types of strategies, the cognitive strategy was mostly favoured by the male students, and metacognitive strategy was favoured by the female students. Nevertheless, their metacognitive or cognitive reading strategies preference does not significantly differ in their reading comprehension score. The interaction between two independent variables did not significantly happen in this research. The choice of using certain reading strategy was not determined by the category of gender. In other words, a certain type of gender using a certain type strategy did not give better results in reading comprehension.
Model answers for Yes/No questions from EFL students in public senior high schools
Authors: Dirgeyasa I Wayan
Published: October 2017

This research aims to find out the typical categories of answers to Yes/No questions most used by students at selected Public Senior High Schools in Medan, Indonesia. These schools were classified into top favorite, medium favorite and non-favorite schools. Through a stratified clustered random sampling technique, six schools were chosen consisting of two schools from each classification. A number of 40 students were chosen from three class X, three class XI and three class XII at each of the six chosen schools, making a total sample of 720 students with 360 sets of dialogue scripts. Data was collected through documentation-recording dialogues. The data was transcribed and analyzed by descriptive analysis. The results of the research showed that: 1) the categories of the students’ answers to the Yes/No questions were distributed variously in terms of the six models. However, the distribution of the answers was not proportionally equal amongst all the models, 2) the dominant distribution of the answers was the third model with the formula Yes/No+additional information such as confirming, supporting, etc., reaching 37% of the total answers, whilst the least common models were the sixth and fourth categories respectively, which had 1% and 3% of the answers respectively, and finally 3) there was no significant difference in the distribution of the students’ answers in terms of the class of school whether top favorite, medium favorite or non-favorite. In conclusion, the ways to answer Yes/No questions need to be developed amongst students by their teachers by teaching and learning using natural, real life-like situations and in contextual ways.
Lessons from experience: ESL student teachers' reflection during practicum through reflective journals
Authors: Mohd Ariff Albakri Intan Safinas , Abdullah Mohd Hassan , Jusoh Ahmad Jazimin
Published: October 2017

Reflection is a prospective alternative in exploring student teachers’ thinking during practicum. The data gained from student teachers’ reflection are significant in informing teacher education programs on how to equip pre-service teachers to become quality teachers. It is also crucial in addressing issues and conflicts highlighted by student teachers when they interact with the real context. This study is conducted with six semester seven student teachers undergoing their Bachelor in Education with honors Teaching English as a Second Language (TESL) program. The student teachers were asked to write reflective journal entries throughout the 14 weeks of their teaching practicum experience. The aim of the study is to identify the focus of the student teachers’ reflection and the challenges faced by them during practicum. Data were gathered using the reflective journal entries and semi-structured interviews with all the participants. The data were analyzed according to emerging themes. The findings indicated that the student teachers focus on three main themes in their reflections, which are managing learning, pedagogy and teacher attributes. While the challenges highlighted were difficulty in socializing with members of the institution, lack of professional support and lack of ability to manage a classroom.
QAR: Strategy implementation for reading comprehension of recount texts
Authors: Erdiana Nira , Kasim Usman , Juwita Nadia
Published: October 2017

The objective of this research is to find out whether QAR strategy is effective in reading comprehension of recount text. This research uses experimental research design. This research took place at Madrasah Tsanawiyah Negeri Model Banda Aceh. A second grade class was chosen as the research sample, which consisted of 36 students. The research instrument used to gather the data was a set of essay tests, which were divided to pre-test and post-test. The result of the research was analyzed by using paired t-test formula. The calculation result shows that the observed t value is less than t lower critical vaue in the t distribution table (-5.624 2.030) at the 0.05 level of significance with 35 degree of freedom. It means that null hypothesis (H0) is rejected, which proves that Question Answer Relationship strategy effectively improves the second grade students’ reading comprehension of recount text.
Implementaciones en Hardware de técnicas de Radiogoniometría
Authors: Sánchez Tibisay , Redondo Alfredo David , García Andrés Felipe , Gómez Cristina , Betancur Leonardo , Hincapié Roberto Carlos
Published: October 2017

En este artículo se presenta una revisión bibliográfica y un análisis comparativo de implementaciones en hardware de técnicas de Radiogoniometría, también conocidas como Radio Direction Finding (RDF), que permiten identificar la mejor opción para implementar estas funcionalidad en actividades de gestión del espectro en países en vía de desarrollo. Dentro de las implementaciones tratadas se incluyen técnicas clásicas como Pseudo-Doppler y técnicas avanzadas de alta resolución como MUSIC. Se presentan diferentes alternativas de hardware para realizar las implementaciones las cuales incluyen SDR (Software Defined Radio), FPGA (Field Programmable Gate Array) y DSP (Digital Signal Processor); a la vez que se incluyen algunas configuraciones híbridas dónde se mezcla el software y el hardware con el fin de optimizar recursos de tiempo y dinero. Adicionalmente se muestran algunas aplicaciones comerciales que emplean técnicas de geolocalización basadas en información de ángulos de llegada, tiempos de llegada u otros parámetros que permiten realizar el proceso de triangulación o trilateración según sea el caso.
Influencia de la presión de contacto sobre los parámetros de diseño de pavimentos asfálticos usando modelos de elementos finitos
Authors: Pallares Muñoz Myriam R. , Pulencio Díaz Julián A.
Published: October 2017

Se evalúa la influencia de la presión de contacto de una carga dual sobre los parámetros de diseño de pavimentos asfalticos por medio del modelador de elementos finitos EverStressFE 1.0 intentando reproducir de una manera más ajustada la forma de la huella y la intensidad de esfuerzo generados por las llantas de los vehículos. Para la validación se empleó el software multicapa elástico EverStress© 5.0. Los resultados de las deformaciones llevaron a concluir que los diseños de pavimentos asfálticos realizados con métodos analíticos pueden estar ligeramente sobredimensionados y en consecuencia elevar los costos de construcción de los pavimentos. Este estudio traza una ruta para analizar la sensibilidad de distintos factores que pueden afectar el diseño de pavimentos asfalticos. Se espera en próximas investigaciones integrar condiciones dinámicas introduciendo resultados obtenidos de pruebas de campo a escala real.
Regionalización de curvas IDF para el uso de modelos hidrometeorológicos en la Sabana Occidental del departamento de Cundinamarca
Authors: Becerra Oviedo Jazmín Andrea , Sánchez Mazorca Liza Fernanda , Acosta Castellano Pedro Mauricio , Díaz Arévalo José Luis
Published: October 2017

En este trabajo se presenta la regionalización de las curvas de intensidad-duración y frecuencia a partir del uso de diferentes modelos hidrometereológicos, tomando como área de estudio la Sabana Occidental del departamento de Cundinamarca-Colombia. Para esto, se realiza el respectivo cálculo de las curvas IDF a partir del análisis de las intensidades registradas en los pluviógrafos de siete estaciones meteorológicas ubicadas en la región, se utiliza el método de Gumbell y las respectivas pruebas de bondad de ajuste. Se aplican diferentes técnicas como la regresión lineal y la determinación de los coeficientes de correlación para la interpolación de las intensidades y los parámetros alfa y U. En la regionalización de las intensidades para la zona de estudio, se aplica un método estadístico basado en la correlación lineal de las intensidades en función de las variables topográficas de la región (altitud, latitud y longitud). En este caso se analizan las diferencias encontradas usando como elementos de interpolación las intensidades registradas y los parámetros Alfa y u.
Presencia de mercurio en la especie Pimelodus grosskopfii “Capaz” en el departamento del Huila
Authors: García Gómez Ángela Goretty , Parejo Pérez Andrea Ximena , Vela Bonilla Lina Margarita , Coronado Cuenca Lilia Vanesa
Published: October 2017

En el presente trabajo se realizaron mediciones para determinar la presencia de Mercurio orgánico (metilmercurio) en la especie Pimelodus grosskopfii “Capaz” en el Departamento del Huila; para ello se determinó el contenido de mercurio total de 35 muestras de peces los cuales fueron capturados entre finales de noviembre y principios de diciembre del año 2012 en los municipios de Hobo, Gigante, vereda de Puerto Seco, Yaguará y Neiva, presentando niveles de mercurio todos los especímenes capturados; adicional a esto se determinó el análisis de riesgo al cual puede estar expuesta la población sensible como son los pescadores, debido al consumo de esta especie, por medio del índice de riesgo Hazard quotient HQ reportando valores inferiores a uno.
Software de ingeniería especializado en el diseño y simulación de plantas de tratamiento de agua residual: revisión
Authors: Sánchez Ramírez J. E. , Mejía Fajardo A. , Amorocho Cruz C. M.
Published: October 2017

Este documento presenta una revisión sobre los programas más utilizados para la simulación, diseño y control de plantas de tratamiento de agua residual. Se plantea la posibilidad de utilizar este tipo de herramientas para investigación, ambientes profesionales y de docencia. Este documento recopila el software más utilizado, teniendo en cuenta que estas herramientas permiten mejorar el rendimiento, control y la optimización de las plantas de tratamiento de agua residual.
Variabilidad espacial de las propiedades físicas de un suelo Fluventic Ustropepts en la cuenca baja del río Las Ceibas - Huila
Authors: Vargas S. Rocio Del Pilar , Serrato C. Fernando , Torrente Trujillo Armando
Published: October 2017

Se estudió la variabilidad espacial de algunas propiedades físicas del suelo asociadas a cultivos de caña, pasto y moringa en un “Fluventic Ustropepts” de la Cuenca baja del Rio Las Ceibas. Se hizo muestreo con grilla de 50 m x 50 m en 26 puntos para los análisis físicos, 8 pruebas de infiltración en muestreo aleatorio simple y 3 muestras integradas para análisis químicos en un área de 6.5 ha. El estudio consta de 5 etapas: 1) recolección de muestras y análisis de las propiedades físicas y químicas del suelo, 2) análisis estadístico y descriptivo de las variables usando los software Statgraphic Centurión XVIII y Excel 2010, 3) análisis geoestadístico basado en la interpolación por el método Kriging con software GS+10, 4) análisis multivariado de las componentes principales generando un gráfico bidimensional (biplot) con InfoStat y 5) elaboración de mapas de variabilidad espacial de las propiedades físicas del suelo por medio de software Surfer 10 para la implementación del plan de cultivos y los mapas de uso del suelo, por medio de los software ArcGis 10. La infiltración del suelo resultó extremadamente heterogénea con un coeficiente de variación del 74,5% y dependencia moderada con rango de alcance de 610,9 m. Se delimitaron tres sectores para los cultivos mencionados, basados en los análisis del suelo según el uso potencial del suelo.
Estudio multifactorial de resistencia ultima a tensión paralela a la fibra en muestras de guadua angustifolia Kunth
Authors: Takeuchi T. Caori , Duarte T. Mauricio , Alarcón G John E. , Olarte F. Jairo F.
Published: October 2017

Este artículo presenta la relación de la resistencia última a tensión paralela a la fibra de probetas de Guadua angustifolia procedentes de cuatro zonas del municipio de Pitalito-Huila, con factores como sección inferior, medio o superior y zona, determinada mediante un análisis de varianza multifactorial. La metodología para el corte de los culmos, obtención de las probetas y pruebas de resistencia a tensión, se basó en las normas NTC5300, NTC5525, NSR10 e ISO/TC 165N315, y en los protocolos para corte de culmos, probetas y determinación de la resistencia a tensión paralela a la fibra de la Universidad Nacional de Colombia sede Bogotá. Fueron ensayadas 120 probetas en la Universidad Nacional de Colombia sede Bogotá. El promedio de resistencia a la tensión paralela fue de 61,0 Mpa. El análisis multifactorial del diseño experimental, permitió identificar la significancia estadística de los factores sección y zona sobre la resistencia a la tensión con un valor-p inferior a 0,05 y un nivel de confianza del 95%, la interacción de segundo orden no fue significativo.
Evaluación sensorial en Café Espresso. Una Comparación entre Jueces Internacionales
Authors: Gutiérrez Guzmán Nelson , Murgueitio Cortes Javier , Peña Gómez Nataly
Published: October 2017

Se evaluaron sensorialmente tres tipos de cafés especiales comerciales y un café de procedencia Huila recién tostado, las muestras se prepararon como café espresso y se evaluaron como bebida de consumo; el panel sensorial estuvo compuesto por tres catadores de Estados Unidos, tres cata- dores Europeos y cuatro catadores colombianos. Las muestras fueron evaluadas sensorialmente de acuerdo a la metodología de la Asociación Americana de Cafés Especiales (SCAA). Los resultados mostraron diferencias estadísticamente significativas (P < 0,05) para la evaluación de las muestras, según la procedencia del evaluador; en cuanto a las notas reportadas por los tres tipos de evaluado- res, los catadores estadounidenses reportaron notas asociadas a madera y cacao, mientras que los catadores colombianos reportaron notas asociadas a frutos rojos y amarillos.
LEPIDOSTROMA TERRICOLENS N.G.N.SP., EINE BASIDIOLICHENE DER SIERRA NEVADA DE SANTA MARTA (KOLUMBIEN)
Authors: Mágdefrau Karl , Winkler Sieghard
Published: October 2017

Describimos el Basidioliquen Lepidostroma terricolens n.g.n.sp. Está compuesta de la Cloroficea Coccomyxa y el hongo Clavulinopsis.
ECOLOGIA MARINA Y EL FUTURO DE LA HUMANIDAD
Authors: Noodt Wolfram
Published: October 2017

Hoy haré un intento de ordenar y presentar para la discusión conceptos y puntos de vista ya conocidos. No hace más de 10 años comenzó a divulgarse una nueva forma de visualizar hechos tradicionales, la que debería conducir a corto plazo un bien común para la humanidad. Diferentes causas, entre las cuales juegan un papel las posibilidades de observar desde el exterior a "nuestro pequeño planeta celeste"; ello induce en cada vez más gente una nueva convicción, que yo deseo denominar "sentimiento de una comunidad en un espacio reducido" .