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[en] The research compares the degree to which four organizations use evaluations to identify outcomes and to improve their practice. The studied organizations (a nonprofit organization (NGO), a federal agency, a local government and a public university) implement natural resource management projects in a terrestrial biosphere reserve of Mexico. Framed in a case study, an analysis of institutional documents was combined with semi-structured interviews to gain access to the information. The NGO has the most appropriate evaluation system to identify compliance with conservation and development objectives. In contrast, the local government completely lacks evaluative procedures.
[en] The principal objective of this research is to analyze the impact of the earthquake of September 05, 2012 on a set of sixteen Global Navigation Satellite System (GNSS) stations located in Costa Rica. This is an explanatory investigation based on the calculation of weekly free solutions, which were later combined to obtain a final solution which was in turn used to generate time series that show variations in the position of the stations. It was observed that GNSS stations located at a maximum distance of 140 km from the epicenter of the earthquake experienced changes in both their position and in the magnitude of their speed, with the stations located in the Peninsula de Nicoya being the most affected. It is concluded that the event studied produced significant changes in the position of thirteen of the analyzed stations, while three stations were not affected by the earthquake. (author)
[es]El objetivo de esta investigacion es determinar el impacto en un conjunto de dieciseis estaciones GNSS localizadas en Costa Rica, tras el terremoto del 05 de septiembre de 2012. La investigacion es de tipo explicativa y el enfoque que se utilizo es el calculo de soluciones semanales libres, las cuales fueron luego combinadas para estimar la solucion final. Basado en esta, se generaron series temporales que muestran la variacion en el tiempo de la posicion de las estaciones. Como resultado, se observa que las estaciones GNSS, localizadas a una distancia maxima de 140 km con respecto al epicentro del evento, sufrieron cambios tanto en su ubicacion como en la direccion del movimiento y en la magnitud de su velocidad, siendo las estaciones ubicadas en la peninsula de Nicoya las que presentan los mayores cambios. Se concluye que el evento estudiado modifico de forma significativa la posicion de trece de las estaciones analizadas, mientras que tres no fueron afectadas. (autor)
[en] Polymers are known to improve the fatigue resistance of sphalt mastics. However, undesirable results can be obtained if the polymer is not successfully integrated into the bitumen binder. The goal of this work is to evaluate the effect of the addition of three selected polyolefins on their mastic’s fatigue performance. Low and high density polyethylenes (LDPE and HDPE) and polypropylene (PP) were chosen and used at the concentration of 4 wt.%. A dissipated energy approach was used in order to analyze the fatigue resistance, at 25 ºC, of the three composites studied. Dynamic time sweeps at and above the linear viscoelastic threshold were carried out. Based on that, the results demonstrated a better improvement when the LDPE was considered. For that binder, fluorescence optical microscopy observations at 25 ºC provided morphological evidence of a more homogeneous bitumen-polymer distribution which could be behind the improved fatigue behavior.
[es]El uso de polímeros mejora la resistencia a la fatiga de los másticos asfálticos. Sin embargo, se pueden obtener resultados no esperados si el polímero no se integra eficientemente en el ligante bituminoso. El objetivo de este trabajo es evaluar el efecto de la adición de 3 poliolefinas sobre el comportamiento a la fatiga. Se seleccionaron polietilenos de baja y alta densidad (PEBD y PEAD) y polipropileno (PP) que se usaron al 4 % en peso. Se empleó una metodología basada en la energía disipada, a 25 ºC. Se realizaron ensayos dinámicos de barrido de tiempo en el límite y por encima del intervalo de viscoelasticidad lineal, que demostraron un mejor comportamiento para el mástico que contenía PEBD. Para él, se observó a través de microscopía óptica de fluorescencia que la distribución de polímero en el betún era mucho más homogénea, y éste podría ser el motivo del comportamiento mejorado.
[en] The chapter presents the methodology for evaluation, including: evaluative approach; evaluation questions; construction and validation of criteria; construction and validation of the questionnaire; study respondents; awareness and application of questionnaires and how the data was analyzed
[en] We present data and analysis of the laser-induced ablation of pure tantalum (Ta, Z=73). We have identified different physical regimes using a wide range of laser pulse durations. A comparison of the influence of strongly varying laser pulse parameters on high-Z materials is presented. The crater depth caused by three different laser systems of pulse duration Δτ = 5 ns and wavelength λ = 1064 nm, Δτ = 35 ps, λ = 355 nm and Δτ =8.5 fs, λ = 790 nm are analyzed via confocal microscopy as a function of laser fluence and intensity. The minimum laser fluence needed for ablation, called threshold fluence, decreases with shorter pulse duration from 1.10 J/cm for the nanosecond laser to 0.17 J/cm for the femtosecond laser.
[en] Objective: To assess the episodes of pneumonia and diarrhea in vaccinated and unvaccinated children under 60 months of age. Methods: This descriptive cross-sectional study was carried out at Darul Sehat Hospital and SESSI, Karachi in the Department of Pediatrics from 1st November 2018 to 3rd February 2019. An interview based questionnaire was administered and selection of participants was done by convenience sampling. Total of 196 participants were selected for interview. Results: Total 196 participants were interviewed which included mothers of children between the age group of 1- 60 months. The questions were entered on the questionnaire after taking consent from the mothers. Among them, males were 98 (52.7%) and females were 88(47.3%). One hundred seventy two (88.7%) children were vaccinated for pneumococcal and rotavirus whereas unvaccinated children were 22(11.3%). There was an incidence of 66(63.5%) for loose watery diarrhea. In vaccinated children, grading of diarrhea was found to be severe cases as 30 (34.9%), moderate cases as 27 (31.4%) and mild cases as 29(33.7%). For unvaccinated children, severe cases were 12 (66.7%) and for mild and moderate cases were (11.1%) and 04(22.2%) respectively with p value of 0.035. As compared to their unvaccinated counterparts, the frequency of severe pneumonia was far less than cough and cold in vaccinated children (p<0.001 Conclusion: There is significant reduction in cases of severe pneumonia in children receiving pneumococcal vaccine as compared to children receiving Rota vaccine there is moderate reduction in cases of severe diarrhea. The overall coverage of Pneumococcal and Rota vaccines was higher in our sample population. Efforts should be made to increase the awareness of Rotavirus vaccination in order to have better coverage in future. (author)
[en] Artichoke has been used for a long time in the traditional medicine against dyspeptic complaints and as a liver protector due to its choleretic and cholagogue effects. Chlorogenic acid, the main ingredient of artichoke is known to show hepatoprotector, anticancer, anti-obesity and antioxidant activities. In this study, antioxidant activity and chlorogenic acid quantification were performed using the samples of artichoke as fresh, boiled, frozen, boiled frozen, canned, fresh leaf and dry leaf. Potential antioxidant activity was evaluated using DPPH assay. Flavonoid and phenolic contents were determined by Aluminum chloride colorimetry and Folin-Ciocalteu methods. The amounts of colorogenic acid in the samples were determined by HPLC-DAD system. The results have shown that highest chlorogenic acid content was determined in the 10-minute frozenboiled sample (0.01441 mg/100g), followed by canned (0.01043 mg/100g), 20-minute cooked artichoke (0.001912 mg/100g), fresh artichoke (0.001519 mg/100g) and frozen artichoke (0.0004 mg/100g). The antioxidant activity results have revealed that highest % DPPH capture effect was observed in the cooked artichoke sample (ED50 =1.949 mg/ml). The total flavonoid content was equivalent to quercetin (43.859 mg QE/100g) whereas total phenolic content equalled to gallic acid (14.640 mg GAE/100g). The antioxidant activity and the amounts of colorogenic acid were found to be the highest in the cooked artichoke sample whereas the lowest antioxidant activity observed in canned artichoke. The results show that the heat treatment applied for storage can positively affect the amount of chlorogenic acid and antioxidant activity. (author)
[en] To determine the time from onset of symptoms to start of fibrinolysis and treatment in acute ST elevated myocardial infarction patients and identify the factors which cause delay in treatment. Methods: A cross sectional study was conducted at National Institute of Cardiovascular Diseases, Karachi on 360 conveniently selected patients of ST elevated myocardial infarction from July to September in the year 2017. Structured questionnaire was used to obtain detailed information on socio-demographics, factors which cause delay and timing of onset of symptoms to arrival of patient in emergency ward. Results: Overall, the total average time from the start of symptoms to initiation of treatment was 119.85±63.32 minutes. Only 5.1% patient reached within one hour while 57.7% reached within two hours. Old age group of 60 and above was positively associated with timely arrival (OR=2.75, 95% CI 1.33-5.68, p=0.006). Significant positive association of using personal car as mode of transport to reach the hospital (OR=5.25, 95% CI 2.94-9.35, p<0.001) was also found as compared to using ambulance. Distance from facility was suggestive of negative association in the model but was statistically insignificant. Conclusion: According to the findings of this study, more than one third of patients reached the hospital within two hours of initiation of symptoms while only 5.1% reached within one hour. The delay was mostly pre-hospital attributed to arranging transport, stay at first medical contact and time taken from first medical contact to the hospital. (author)
[en] Plants rely on a variety of dispersal vectors to transport their seeds, including both abiotic and biotic vectors. Distribution patterns of seedlings may be different owing to these differences in seed dispersal vectors; however, few studies have examined this assumption. In this study, we compared several seedling parameters (number, diameter, height, and distance from the mother tree) between a wind-dispersal species, Liquidambar formosana, and a rodent-dispersal species, Quercus acutissima, growing in the same bamboo forest and also examined how the type of dispersal vector influenced the spatial distribution of seedlings. One-hundred and seventy-four individual L. formosana seedlings and 84 individual Q. acutissima seedlings were recorded, and the average diameter and height of Q. acutissima seedlings were significantly larger than those of L. formosana seedlings. The seedling density of L. formosana showed a single-peak whereas Q. acutissima showed multiple peaks at different distances from the parent plant. The average dispersal distance of Q. acutissima seedlings (11.13 ± 9.45 m) was much further than that for L. formosana (7.71 ± 6.74 m). The results of this study suggest that rodent dispersed plants may have an increased chance of survival and a longer dispersal distance than wind-dispersed plants, and that animal-dispersal might be more conducive to the spread and regeneration of plant populations. (author)
[en] Objective: To compare and evaluate the relapse tendency of two types of fixed lingual retainers using Little's irregularity index for a follow-up of one year. Study Design: Randomised clinical trial. Place and Duration of Study: Department of Orthodontics, Dr. Ishrat Ul Ebad Khan Institute of Oral Health Sciences and Dow Dental College in Dow University of Health Sciences, Karachi, Pakistan, from November 2017 to March 2019. Methodology: A total of 54 patients were recruited and divided into two groups by random allocation. Subjects who have completed fixed appliance (MBT) orthodontic treatment and non extraction cases with moderate crowding in the lower arch were included. Subjects with caries, restoration, fracture or missing lower anterior teeth were excluded. Group 1 received fiber reinforced composite (FRC) retainers and group 2 received multistranded stainless steel (MSW) retainers. They were recalled after every three months interval for one year. Relapse tendency of retainers using Little's irregularity index was evaluated at each visit. Results: Comparison of relapse tendency between two retainers showed statistically significant results (p<0.05). The mean difference of CPD between two retainers at T0 was found to be 0.09 mm (p=0.01). At T1, it was determined to be 0.3 mm (p=0.022), and at T2 it was found to be 0.3 mm (p=0.008). At T3 and T4, it was found to be 0.5 mm (p<0.001) and 0.5 mm (p=0.002), respectively. All mean differences were statistically significant. Conclusion: Fiber-reinforced retainers are more effective in preventing the mandibular incisor relapse. The results of the study also suggest that the irregularity of the dentition increases with the passage of time. (author)