11 research outputs found

    Fluid-transport evaluation of lateral condensation, GuttaCore™ and continuous wave of obturation techniques

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    To achieve success in endodontic treatment, the root canal system should be as sealed as possible with suitable material such as gutta-percha and sealer. Objective: This study compare the apical leakage of roots obturated with GuttaCore™, lateral condensation, and continuous wave obturation through a computerized fluid-transport system. Material and methods: Fifty-two freshlyextracted upper molars were used. The disto-buccal roots were cut and standardized to 10 mm long. The root canals were prepared at working length with WaveOne primary reciprocating files. The specimens were randomly divided and filled by one of the following obturation techniques: GuttaCore™, lateral condensation or continuous wave obturation, using SILCO sealer. The positive controls were left unfilled and the negative controls were totally coated with cyanoacrylate and three layers of nail polish. The roots were stored in relative humidity for 72 h at 37°C, allowing the sealer to set. After this period, the roots were connected to a computerized fluid-transport system, and the apical leakage was analyzed. Results: The results were expressed in µL.cmH2O-1.min-1 x10-4 1.36 atm. The data were statistically analyzed using one-way ANOVA and Tukey´s tests. The specimens of the positive control group showed extreme amounts of apical leakage. There was no leakage in the negative ontrols. The statistical analysis indicated that continuous wave obturation and GuttaCore™ showed lower leakage than the lateral condensation technique (p0.05). Conclusion: Continuous wave obturation and GuttaCore™ showed lower leakage than the lateral condensation technique. There was no difference between the continuous wave obturation and GuttaCore™. The fluid-transport system used in this study allowed an accurate quantitative measurement of leakage using simpler equipment.To achieve success in endodontic treatment, the root canal system should be as sealed as possible with suitable material such as gutta-percha and sealer. Objective: This study compare the apical leakage of roots obturated with GuttaCore™, lateral condensation, and continuous wave obturation through a computerized fluid-transport system. Material and methods: Fifty-two freshlyextracted upper molars were used. The disto-buccal roots were cut and standardized to 10 mm long. The root canals were prepared at working length with WaveOne primary reciprocating files. The specimens were randomly divided and filled by one of the following obturation techniques: GuttaCore™, lateral condensation or continuous wave obturation, using SILCO sealer. The positive controls were left unfilled and the negative controls were totally coated with cyanoacrylate and three layers of nail polish. The roots were stored in relative humidity for 72 h at 37°C, allowing the sealer to set. After this period, the roots were connected to a computerized fluid-transport system, and the apical leakage was analyzed. Results: The results were expressed in µL.cmH2O-1.min-1 x10-4 1.36 atm. The data were statistically analyzed using one-way ANOVA and Tukey´s tests. The specimens of the positive control group showed extreme amounts of apical leakage. There was no leakage in the negative ontrols. The statistical analysis indicated that continuous wave obturation and GuttaCore™ showed lower leakage than the lateral condensation technique (p0.05). Conclusion: Continuous wave obturation and GuttaCore™ showed lower leakage than the lateral condensation technique. There was no difference between the continuous wave obturation and GuttaCore™. The fluid-transport system used in this study allowed an accurate quantitative measurement of leakage using simpler equipment

    Internal inspection of semi-transparent objects by digital holographic micro-tomography

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    The combined use of digital holographic microscopy and computer tomography, here named digital holographic micro-tomography, is used to examine the interior of transparent channels. The proposed method is used to identify internal obstacles inside of transparent troughs having slightly different refractive index. The method is based in the acquisition of a set of digital holograms of the specimen whereas it is axially rotated from 0° to 180°. The phase differences retrieved from the obtained holograms are the inputs to a computerised axial tomography procedure. The technique has been numerically modelled in order to find the optimal tomographic conditions and also to realise the minimum difference of refractive index the method could detect. The obtained results show the feasibility of the proposed method for the non-destructive evaluation of transparent micro-objects.Fil: Monroy Ramirez, F. A.. Universidad Nacional de Colombia; ColombiaFil: Dolinko, Andrés Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Garcia Sucerquia, J.. Universidad Nacional de Colombia; Colombi

    Análisis de Costos en la Producción de Quesos Artesanales. Estudio de Caso: Quesería el Bejucal

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    Revista Iberoamericana De Bioeconomía Y Cambio Climático, 5(10), 1222–1247La actividad económica resultado de la elaboración de quesos artesanales, es de gran importancia para la economía local, no existe un estudio de este tipo que permita a los productores conocer a detalle los costos de manufactura del queso artesanal, actualmente los productores sólo tienen aproximaciones y sus precios de venta los determinan de acuerdo al comportamiento del mercado, sin tener certeza acerca del margen de utilidad. Por ello, se realizó este trabajo que consistió en determinar la estructura de costos en cada tipo de queso artesanal, que se elabora en la Quesería “El Bejucal”. Esta empresa es una de las más emblemáticas debido a su tradición y prestigio, ubicada en el municipio de Balancán, Tabasco, y cuya marca está protegida ante el Instituto Mexicano de la Propiedad Industrial (IMPI). Se realizaron cálculos basados en la clasificación de costos directos, indirectos y gastos de administración y ventas. Se encontró que el queso de poro es el producto que más alto costo de producción tiene, respecto a los demas productos, debido principalmente al elevado costo del material de empaque. Sin embargo, el ingreso por la comercialización del queso de poro corresponde al 70% y el restante a los otros quesos; el queso de poro es de pasta friable,blanda y prensada; ligeramente madurado, elaborado a partir de leche bronca, se comercializa en piezas de aproximadamente 300 gUniversidad Nacional Autónoma de Nicaragua, León. Escuela de Ciencias Agrarias y Veterinarias. Departamento de Agroecologia

    Biological Activities of Seven Medicinal Plants Used in Chiapas, Mexico

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    Seven medicinal plants from Chiapas, Mexico, used by Native Americans were analyzed, aiming to improve the understanding of their medicinal properties through the evaluation of various biological activities, i.e., bactericidal, antioxidant, α-glucosidase inhibition, and toxicity, to provide a scientific basis for the management of infectious and hyperglycemic diseases in the Mexican southeast. Plant extracts were obtained from Cordia dodecandra, Gaultheria odorata, Heliotropium angiospermum, Justicia spicigera, Leucaena collinsii spp. collinsii, Tagetes nelsonii, and Talisia oliviformis through maceration techniques using methanol and chloroform (1:1). Minimum Inhibitory Concentration (MIC) was employed to determine the antibacterial activity against Staphylococcus aureus, Enterobacter faecalis, Escherichia coli, Enterobacter aerogenes, Enterobacter cloacae, Klebsiella pneumoniae, and Pseudomonas aeuroginosa. The antiradical/antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays and antihemolytic activity using the 2,2’-Azobis(2-amidinopropane) dihydrochloride radical (APPH). The anti-α-glucosidase activity was evaluated in vitro through the chromogenic PNPG assay. The toxicity was assessed using the brine shrimp lethality assay. The highest antimicrobial activity was displayed by T. nelsonii, mainly against E. faecalis and P. aeuroginosa. The extracts of L. collinsii, J. spicigera, and T. nelsonii possess antioxidant properties with EC50 < 50 μg/mL. J. spicigera and T. nelsonii extracts showed the highest antihemolytic activity with IC50 < 14 μg/mL. T. nelsonii exhibited a remarkable inhibitor effect on the α-glucosidase enzyme and the greatest toxic effect on Artemia salina with IC50 = 193 ± 20 μg/mL and LD50 = 14 ± 1 μg/mL, respectively. According to our results, G. odorata, J. spicigera, T. nelsonii, and T. oliviformis extracts contained active antimicrobial compounds. At the same time, T. nelsonii stands to be a possible source of effective antineoplastic and antihyperglycemic compounds

    Phenolic Profiles and Biological Activities of Extracts from Edible Wild Fruits Ehretia tinifolia and Sideroxylon lanuginosum

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    Ehretia tinifolia Linnaeus (Boraginacea) and Sideroxylon lanuginosum Michaux (Sapotaceae) are wild fruits consumed in North America and are appreciated for their pleasant flavor and sweet taste. However, details regarding their composition and biological properties in the available literature are scarce. This study reports the phenolic composition, antioxidant, antiproliferative activities, and digestive enzymatic inhibition of amberlite-retained methanolic extracts from both fruits. Results revealed that these wild fruit extracts are rich in antioxidants. S. lanuginosum had lower phenolic but higher flavonoid contents (21.4 ± 1.5 mg GAE/100 g FW and 6.42 ± 0.9 mg CE/100 g FW) than E. tinifolia (64.7 ± 2.6 mg GAE/100 g FW and 5.1 ± 0.4 mg CE/100 g FW). HPLC-DAD-MS/MS analysis showed rosmarinic acid as a major polyphenol in E. tinifolia and quercetin glucoside in S. lanuginosum. Polyphenols content in E. tinifolia was related to a significant free radical scavenging ability: DPPH (EC50 = 0.32 ± 0.03 mg/mL), TEAC (4134 ± 9.7 μM TE/g dry extract), and hemolysis inhibition (IC50 = 58.55 ± 2.4 μg/mL). Both extracts were capable of inhibiting α-glucosidase, partially inhibiting α-amylase, and showed no inhibition against lipase, while showing antiproliferative activity against HeLa, HT-29 and MCF-7 cancer cell lines. Our study revealed that these wild fruit extracts are rich in health-beneficial phytochemicals and hold significant potential for elaborating functional foods

    The resilience of Triatoma dimidiata: An analysis of reinfestation in the Nicaraguan Chagas disease vector control program (2010?2016)

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    Background: The control of Triatoma dimidiata, a major vector of Chagas disease, was believed to eliminate Trypanosoma cruzi transmission in Central America. This vector was known for its ability to repeatedly reinfest human dwellings even after initial insecticide spraying. Current vector control programs assume that community-based surveillance can maintain low levels of infestation over many years, despite a lack of evidence in the literature to corroborate this assumption. This study aims to evaluate long-term reinfestation risk in the Nicaraguan vector control program from 2010 to 2016. Methods: We collected data from a cohort of 395 houses in Pueblo Nuevo, Nicaragua. Primary data were collected through a field survey to assess post-intervention levels of T. dimidiata house infestation in 2016, two years after the large-scale insecticide spraying. We obtained secondary data from the records about past infestation levels and control activities between 2010 and 2015. Multilevel mixed-effects logistic regression analyses were used to identify factors associated with post-intervention house infestation. Results: The control program effectively reduced the infestation level from 2010 to 2014. Community-based surveillance was introduced in 2013; however, post-intervention infestation in 2016 had nearly reached pre-intervention levels in rural villages. Post-intervention house infestation was positively associated with poor wall construction, roofing tiles piled in the peri-domestic areas or the presence of dogs. Interestingly, the odds of post-intervention house infestation were one-fifth less when villagers sprayed their own houses regularly. Past infestation levels and the intensity of government-led insecticide spraying did not explain post-intervention house infestation. Conclusions: The vector control program failed to offer sustained reductions in T. dimidiata house infestation. This experience would suggest that community-based surveillance is an insufficient approach to suppressing T. dimidiata house infestation over many years. This study provides evidence to suggest that control policies for T. dimidiata should be reconsidered throughout Central America

    Data from: Jaguar Movement Database: a GPS-based movement dataset of an apex predator in the Neotropics

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    The field of movement ecology has rapidly grown during the last decade, with important advancements in tracking devices and analytical tools that have provided unprecedented insights into where, when, and why species move across a landscape. Although there has been an increasing emphasis on making animal movement data publicly available, there has also been a conspicuous dearth in the availability of such data on large carnivores. Globally, large predators are of conservation concern. However, due to their secretive behavior and low densities, obtaining movement data on apex predators is expensive and logistically challenging. Consequently, the relatively small sample sizes typical of large carnivore movement studies may limit insights into the ecology and behavior of these elusive predators. The aim of this initiative is to make available to the conservation-scientific community a dataset of 134,690 locations of jaguars (Panthera onca) collected from 117 individuals (54 males and 63 females) tracked by GPS technology. Individual jaguars were monitored in five different range countries representing a large portion of the species’ distribution. This dataset may be used to answer a variety of ecological questions including but not limited to: improved models of connectivity from local to continental scales; the use of natural or human-modified landscapes by jaguars; movement behavior of jaguars in regions not represented in this dataset; intraspecific interactions; and predator-prey interactions. In making our dataset publicly available, we hope to motivate other research groups to do the same in the near future. Specifically, we aim to help inform a better understanding of jaguar movement ecology with applications towards effective decision making and maximizing long-term conservation efforts for this ecologically important species

    DataS1

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    The archive has 2 files. The first file has general information about captured animals (estimated age, weight, collar used, etc.). The second file has general information on animals' location
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