Multiple Comparisons Of Means Research Articles

Bioestimulante Liplant®: su efecto en Solanum lycopersicum (L.) cultivado en suelos ligeramente salinos

La aplicación de sustancias húmicas, estimula mecanismos bioquímicos, fisiológicos, se han realizado investigaciones que revelan las propiedades y funciones de estas sustancias. El objetivo de esta investigación fue evaluar el efecto de diferentes concentraciones de Liplant® aplicadas vía foliar (1/10, 1/20, 1/30 v/v y un control-agua destilada-) en el crecimiento, producción y calidad de fruto de tomate, y factibilidad económica. Realizándose bajo condiciones de campo y utilizando un diseño de bloques completos al azar, 5 días después del trasplante se midió altura, diámetro de tallo; 65 días después, se consideró peso fresco y seco de frutos, diámetro polar y ecuatorial, número de frutos, rendimiento, acidez titulable, sólidos solubles totales, índice madurez, contenido de vitamina C, pH del jugo del fruto, pérdida de humedad y firmeza de frutos. La factibilidad económica se realizó considerando rendimiento, valor y costo de producción, beneficio neto, costo y la relación beneficio/costo. Se realizaron análisis de varianza y comparaciones múltiples de medias (Tukey HSD p= 0.05). El pH de jugo no mostró diferencias significativas entre concentraciones de Liplant®. Altura, diámetro del tallo, número de frutos, diámetro polar y ecuatorial, peso fresco y seco de frutos, rendimiento, firmeza de fruto, sólidos solubles totales, vitamina C y pérdida de humedad de fruto mostraron valores superiores cuando las plantas se asperjaron con la dilución de Liplant® de 1/30 (v/v). La dilución de 1/30 (v/v) de Liplant® generó un beneficio de $36 753.9 miles de pesos Cubanos por hectárea, un beneficio/costo de $3.60 pesos cubanos y un costo por peso de $0.21.

Effects of crystal refining on wear behaviors and mechanical properties of lithium disilicate glass-ceramics.

The purpose of this study is to improve wear resistance and mechanical properties of lithium disilicate glass-ceramics by refining their crystal sizes. After lithium disilicate glass-ceramics (LD) were melted to form precursory glass blocks, bar (N = 40, n = 10) and plate (N = 32, n = 8) specimens were prepared. According to the differential scanning calorimetry (DSC) of precursory glass, specimens G1-G4 were designed to form lithium disilicate glass-ceramics with different crystal sizes using a two-step thermal treatment. In the meantime, heat-pressed lithium disilicate glass-ceramics (GC-P) and original ingots (GC-O) were used as control groups. Glass-ceramics were characterized using X-ray diffraction (XRD) and were tested using flexural strength test, nanoindentation test and toughness measurements. The plate specimens were dynamically loaded in a chewing simulator with 350 N up to 2.4 × 106 loading cycles. The wear analysis of glass-ceramics was performed using a 3D profilometer after every 300,000 wear cycles. Wear morphologies and microstructures were analyzed by scanning electron microscopy (SEM). One-way analysis of variance (ANOVA) was used to analyze the data. Multiple pairwise comparisons of means were performed by Tukey's post-hoc test. Materials with different crystal sizes (p < 0.05) exhibited different properties. Specifically, G3 with medium-sized crystals presented the highest flexural strength, hardness, elastic modulus and fracture toughness. G1 and G2 with small-sized crystals showed lower flexural strength, whereas G4, GC-P, and GC-O with large-sized crystals exhibited lower hardness and elastic modulus. The wear behaviors of all six groups showed running-in wear stage and steady wear stage. G3 showed the best wear resistance while GC-P and GC-O exhibited the highest wear volume loss. After crystal refining, lithium disilicate glass-ceramic with medium-sized crystals showed the highest wear resistance and mechanical properties.

Accuracy and reliability of tooth length measurements on conventional and CBCT images: An in vitro comparative study.

CONTEXT:The purpose of this study was to evaluate the accuracy and reliability of tooth length measurements using conventional and cone-beam computed tomography (CBCT) imaging techniques.AIM:The aim of this study was to assess the accuracy and reliability of various tooth length measurements made on CBCT scans and conventional imaging techniques [intraoral periapical radiograph (IOPA) and orthopantomogram (OPG)].SETTINGS AND DESIGN:This is an in-vitro comparative study.SUBJECTS AND METHODS:In total, 50 extracted single-rooted premolar teeth were mounted on the dry human mandible. For each extracted tooth, measurements for tooth length, crown length, and root lengths were taken with a Vernier caliper and using three imaging modalities: CBCT, OPG, and IOPA radiographs. The measurements were compared with the gold standard (Vernier caliper).STATISTICAL ANALYSIS USED:One-way analysis of variance was used to compare mean values between the groups that are Vernier caliper, CBCT, IOPA, and OPG. The multiple comparisons of means of tooth length, root length, and crown length were done by Bonferroni test.RESULTS:A significant difference in the tooth length measurements was seen between the measurements taken by CBCT and IOPA and between IOPA and OPG. But, no significant difference was seen between any other groups. The highly significant difference was seen between the root length measurements taken by IOPA and OPG and by CBCT and OPG. However, no significant difference was seen between any other groups. No significant difference was seen in between the crown length measurements taken by Vernier caliper and CBCT and between IOPA and OPG. However, a significant difference was seen between all the groups.CONCLUSIONS:Among the radiographic techniques, CBCT was found to be the most accurate in measuring the tooth, root, and crown lengths.

Alignment efficiency and esthetic performance of 4 coated nickel-titanium archwires in orthodontic patients over 8weeks: A multicenter randomized clinical trial.

The objective of this 4-arm parallel study was to evaluate the alignment efficiency and esthetic performance of 4 coated nickel-titanium archwires over an 8-week period. Patients in the permanent dentition requiring maxillary and mandibular fixed orthodontic treatment with a preadjusted edgewise appliance were eligible for inclusion. Patients attending 4 hospital departments (United Kingdom and Italy) were randomly allocated to 1 of 4 treatment interventions: (1) BioCosmetic (Forestadent, Pforzheim, Germany), 0.017 in; (2) Titanol (Forestadent), 0.016 in; (3) TP Aesthetic (TP Orthodontics, La Porte, Ind), 0.014 in; and (4) Tooth Tone (Ortho Organizers, Calsbad, Calif) 0.016 in. Block randomization with block sizes of 4 and 8 was used to ensure an allocation ratio of 1:1:1:1. The primary outcome was alignment efficiency determined by the reduction in Little's irregularity index (mm). Secondary outcomes were color change using the Commission Internationale de L'Eclairage L*a*b* system and percentage of coating loss. Blinding was only applicable to outcome assessment of alignment efficiency. Regression models with Sidak's multiple comparison of means were used to analyze the data. One hundred fifty patients (300 dental arches) were allocated to the treatment interventions, including 61 male and 89 female subjects with a mean age of 16.60years. The average duration of follow-up was 63.65days. Baseline characteristics for the archwire groups were similar. One patient was lost to follow-up. Five percent (n=15) of the archwires fractured: BioCosmetic, 5.3% (n=4); Titanol, 6.8% (n=5); TP Aesthetic, 5.3% (n=4); and Tooth Tone, 2.7% (n=2). We analyzed 283 dental arches for alignment efficiency. There was no statistically significant difference for mean reduction in irregularity between the archwire groups (P=0.627): BioCosmetic (n=71), 3.86mm (95% CI, 3.31-4.41); Titanol (n=69), 4.51mm (95% CI, 4.00-5.02); TP Aesthetic (n=71), 4.13mm (95% CI, 3.49-4.78); and Tooth Tone (n=72), 4.21mm (95% CI, 3.89-4.46). There was a statistically significant difference between archwire groups for color change (P=0.001) and percentage of coating loss (P=0.001), with BioCosmetic performing best in both parameters. There was no difference between the archwires for alignment efficiency. BioCosmetic performed statistically significantly better than did the other groups for both color change and coating loss. This trial was registered with the East Midlands NHS Research Ethics Committee (12/EM/0190). The protocol was not published before trial commencement.

Brazil nut meal and spray-dried egg powders as alternatives to synthetic methionine in organic laying hen diets

The United States organic poultry industry is currently facing a limitation on dietary inclusion of synthetic methionine (Met). This study investigated Brazil nut protein powder (BNPP), spray-dried egg white (SDEW), and spray-dried egg blend (70:30 albumen: yolk) (SDEB) as alternatives to synthetic Met in organic laying hen diets. A total of 270 Hy-Line Brown laying hens was fed 5 diets from 22 to 38 wk of age, with 6 replicates of 3 adjacent cages per diet and 3 hens per cage. Diets included a commercial control (COM) (non-organic with standard CP and synthetic Met), an organic control (ORG) (with no synthetic Met, but higher CP to meet Met requirements), and 3 organic treatment diets with no synthetic Met, but including BNPP, SDEW, or SDEB at levels to meet Met requirements. Egg production and quality, body weight (BW), feed intake, and manure nutrients and ammonia were assessed. Data were analyzed using the PROC MIXED procedure of SAS, with Tukey's test used for multiple mean comparisons, and P ≤ 0.05 was deemed statistically significant. Body weight was greatest for the COM diet, and feed conversion improved for hens fed egg-based diets compared to controls. Egg weight and production did not differ between COM and treatment diets. The SDEW diet had greater albumen height and Haugh units compared to ORG and BNPP diets and greater percent albumen compared to COM and BNPP diets. Specific gravity was greatest for BNPP fed hens. Manure DM and potash were highest from COM and BNPP diets, respectively. Both egg-based diets increased ammonia flux relative to the COM diet. The BNPP and egg-based diets were lower in cost for $/metric tonne, $/dozen eggs, and $/kg of eggs compared to the ORG diet. The ingredients assessed herein could, therefore, cost-effectively replace synthetic Met in organic hen diets without negatively impacting egg production.

Interfacial Fracture Toughness of Adhesive Resin Cement-Lithium-Disilicate/Resin-Composite Blocks.

Resin composite blocks (RCB) are advocated as alternative to ceramic blocks (CB). Prior to use, adherence to these materials should characterized. This study aimed to test the null hypothesis (H0 ) that material and surface treatment combinations do not influence interfacial fracture toughness (KIC ) of a self-cured adhesive resin cement [RelyX Ultimate (RXU)] to RCB or CB, under nonaged and aged conditions. Two RCB, Lava Ultimate (LU) and Enamic (EN), and one CB, IPS e.max Press (EMP) were used. Half-size [(6 × 6 × 6 × 6 mm)] specimens were prepared for EMP (n = 30), EN (n = 30), and LU (n = 60). RCB specimens were prepared by wet cutting/grinding, while CB specimens were pressed. Surfaces of EMP and EN were preconditioned with hydrofluoric acid (5%); surfaces of LU were sandblasted with either 27 μm alumina (LUS) or 30 μm silica-modified alumina Rocatec soft (LUR). All specimens were bonded with Scotchbond Universal adhesive and RXU. Additionally, twenty (4 × 4 × 4 × 8 mm) RXU specimens were prepared. All specimens were stored in water at 37°C and tested after 1 and 60 days. Interfacial KIC was determined with the notchless triangular prism specimen KIC test. Results were analyzed with two-way ANOVA and Scheffé multiple means comparisons (α = 0.05). Preconditioned and selected fractured surfaces were characterized with scanning electron microscopy. At 24 hours, LUS-RXU and LUR-RXU had significantly higher interfacial KIC than EN-RXU and EMP-RXU and were not different from KIC of RXU. Aging lead to a significant decrease in KIC of RXU and interfacial KIC of LUS-RXU, LUR-RXU, and EMP-RXU; interfacial KIC of EN-RXU was not affected. Based on the results, H0 was rejected. Under the conditions of this study, at 24 hours, interfacial KIC of LUS-RXU and LUR-RXU was superior to EMP-RXU and EN-RXU. Aging in water at 37°C did not affect interfacial KIC of EN-RXU but adversely affected KIC of RXU and the other interfacial KIC . The results suggest that RXU and its adherence to LU and EMP deteriorates upon exposure to water at 37°C. In making clinical decisions related to material selection, practitioners should consider in vitro results.

Businesswomen’s choice of professional dress: Model development for dress perception

The purpose of this study was to explore the relationships between businesswomen’s choice of professional dress and four dress perception variables (ie comfort, employment orientation, appearance labor, availability of professional dress). The choice of professional dress is viewed along the fashion continuum, which ranges from “classic dress” to “innovative dress.” A model was developed based on systems theory, and variables were selected from previous research that relate to an individual’s perception of and attitude toward their professional dress as well as an individual’s population characteristics. Data were collected via an online survey managed by a marketing research company. Results of the multiple regression analysis and mean comparisons testing indicated significant relationships between businesswomen’s choice of professional dress and comfort, appearance labor (ie effort devoted to attire), and availability of professional dress (ie limited store availability) as well as age and education. Based on the findings, academic and practical suggestions as well as recommendations for future research were provided.

Potential influence of κ-casein and β-lactoglobulin genes in genetic association studies of milk quality traits.

ObjectiveFrom a review of published information on genetic association studies, a meta-analysis was conducted to determine the influence of the genes κ-casein (CSN3) and β-lactoglobulin (LGB) on milk yield traits in Holstein, Jersey, Brown Swiss, and Fleckvieh.MethodsThe GLIMMIX procedure was used to analyze milk production and percentage of protein and fat in milk. Models included the main effects and all their possible two-way interactions; not estimable effects and non-significant (p>0.05) two-way interactions were dropped from the models. The three traits analyzed used Poisson distribution and a log link function and were determined with the Interactive Data Analysis of SAS software. Least square means and multiple mean comparisons were obtained and performed for significant main effects and their interactions (p<0.0255).ResultsInteraction of breed by gene showed that Holstein and Fleckvieh were the breeds on which CSN3 (6.01%±0.19% and 5.98%±0.22%), and LGB (6.02%±0.19% and 5.70%±0.22%) have the greatest influence. Interaction of breed by genotype nested in the analyzed gene indicated that Holstein and Jersey showed greater influence of the CSN3 AA genotype, 6.04%±0.22% and 5.59%±0.31% than the other genotypes, while LGB AA genotype had the largest influence on the traits analyzed, 6.05%±0.20% and 5.60%±0.19%, respectively. Furthermore, interaction of type of statistical model by genotype nested in the analyzed gene indicated that CSN3 and LGB genes had similar behavior, maintaining a difference of more than 7% across analyzed genotypes. These results could indicate that both Holstein and Jersey have had lower substitution allele effect in selection programs that include CSN3 and LGB genes than Brown Swiss and Fleckvieh.ConclusionBreed determined which genotypes had the greatest association with analyzed traits. The mixed model based in Bayesian or Ridge Regression was the best alternative to analyze CSN3 and LGB gene effects on milk yield and protein and fat percentages.

WASTE WOOD OF URBAN ORIGIN FOR ENERGY USE

ABSTRACT The increasing demand for energy propels new areas of research in the search for sources that are economically viable and sustainable from an environmental point of view. In this sense, the objective of this study was to characterize a batch from urban wood waste aimed at energy use. We evaluate six different types of waste: solid wood, plywood, chipboard, MDF, OSB, and veneer. The residues were collected in a recycling plant in Piracicaba - SP and were taken to the laboratory to carry out the physical, chemical and thermogravimetric analyses. The experiment was conducted in a completely randomized design with three replicates per treatment (waste). Data analysis was performed by analysis of variance (ANOVA) and the Tukey test applied for multiple comparisons of means. Overall, there were no major differences between the results of solid wood residues and waste panels. Waste analyzed showed potential for energy use. It is recommended further studies to investigate the influence of different panels resins and coatings in its thermal degradation process.

A comparative study of progressive wear of four dental monolithic, veneered glass-ceramics

ObjectivesThis study evaluated the wear performance and wear mechanisms of four dental glass-ceramics, based on the microstructure and mechanical properties in the progressive wear process. MethodsBar (N = 40, n = 10) and disk (N = 32, n = 8) specimens were prepared from (A) lithium disilicate glass-ceramic (LD), (B) leucite reinforced glass-ceramic (LEU), (C) feldspathic glass-ceramic (FEL), and (D) fluorapatite glass-ceramic (FLU). The bar specimens were tested for three-point flexural strength, hardness, fracture toughness and elastic modulus. The disk specimens paired with steatite antagonists were tested in a pin-on-disk tribometer with 10N up to 1000,000 wear cycles. The wear analysis of glass-ceramics was performed using a 3D profilometer after every 200,000 wear cycles. Wear loss of steatite antagonists was calculated by measuring the weight and density using sensitive balance and Archimedes’ method. Wear morphologies and microstructures were analyzed by scanning electron microscopy (SEM). The crystalline phase compositions were determined using X-ray diffraction (XRD). One-way analysis of variance (ANOVA) was used to analyze the data. Multiple pair-wise comparison of means was performed by Tukey's post-hoc test. ResultsLD showed the highest fracture toughness, flexural strength, elastic modulus and crystallinity, followed by LEU and FEL, and FLU showed the lowest. However, the hardness of LD was lower than all the other three types of ceramics. For steatite antagonists, LD produced the least wear loss of antagonist, followed by LEU and FEL, and FLU had the most wear loss. For glass-ceramic materials, LD exhibited similar wear loss as LEU, but more than FLU and FEL did. Moreover, fracture occurred on the wear surface of FLU. ConclusionsIn the progressive wear process, veneering porcelains showed better wear resistance but fluorapatite veneering porcelains appeared fracture surface. Monolithic lithium disilicate glass-ceramics with higher mechanical properties showed more wear loss, however, they did not fracture and produced less wear loss of antagonists.

Biomechanical comparison of four coupled fixation systems for ACL reconstruction with bone socket or full-tunnel on the tibial side

BackgroundTo compare in an animal model the biomechanical properties of four coupled fixation devices currently used in ACL reconstruction. Three out of four devices used a full tibial tunnel with an interference screw, while the other one system used a tibial socket and an adjustable loop suspension device. The null hypothesis is that there are no biomechanical differences between all the techniques tested. MethodsThirty two femur–graft–tibia complexes were mounted on a tensile machine using bovine digital extensor tendons, porcine knees and four different fixation device combinations:–Group A: EndoButton CL and BioRCI–Group B: Rigidfix and Intrafix–Group C: Transfix and Deltascrew–Group D: TightRope-RT with the All-inside GraftLink technique.After a preconditioning with a tensile load of 90N for five minutes, 1000cycles between 0 and 150N were applied to the complex before the final pulled to failure. Stiffness and strength were evaluated at the final pullout, as was the displacement (slippage) at one, 100, 500, and 1000cycles. ResultsThe multiple mean comparison led to a significant difference for the case of stiffness, with worse results in group C compared to group A (p=0.037). Conversely, no differences were found in UFL and slippage between all groups (p>0.05). ConclusionAll the tested systems demonstrated in an animal model sufficient properties for a safe postoperative rehabilitation both for strength and for stiffness and slippage under cyclic loading.

LO54: A descriptive analysis of ED length of stay of admitted patients ‘boarded’ in the emergency department

Introduction: Previous studies have shown a link between Emergency Department (ED) overcrowding and worse clinical outcomes, increased risk of in-hospital mortality, higher costs, and longer times to treatment. Prolonged ED Length of Stay (LoS) of admitted patients awaiting a bed on in-patient units has been identified as a major driver of ED overcrowding. The purpose of this study is to provide a descriptive analysis of ED LoS among admitted patients, and determine the impact of prolonged ED LoS on total hospital in-patient length of stay (IP LoS). Methods: We conducted a single-site retrospective study for the period between January 1-December 31, 2015 at a very high volume community hospital. All patients aged ≥18 years admitted from the ED to acute in-patient Medicine units were identified. We carried out overall descriptive analysis (including analysis of day-of-the-week variability) on ED LoS. The mean total IP LoS for those patients with ED LoS&amp;lt;12 hours, 12-24 hours, and ≥24 hours were calculated and analyzed using ANOVA and Tukey HSD tests. Results: A total of 6,961 individuals were admitted to the medical units over the 12-month period. The median and mean ED LoS for admitted patients were 22.9 hrs (IQR: 13.9 hrs- 33.1 hrs) and 25.6 hrs respectively. Using ANOVA, there was a statistically significant difference in means of ED LoS as a function of the day of the week (p&amp;lt;0.0001), with Mondays having the highest mean ED LoS (27.6 hrs), and Fridays having the lowest (23.1 hrs). The mean IP LoS for those with ED LoS&amp;lt;12 hours, 12-24 hours, and ≥24 hours, were 6.8 days, 6.9 days, and 8.5 days respectively, with a statistically significant difference between group means (p&amp;lt;0.0001). Multiple pairwise comparisons of group means showed a statistically significant (p&amp;lt;0.05) difference between mean IP LOS of those with an EDLOS≥24 hours and those with an EDLOS&amp;lt;24 hours. Conclusion: Preliminary results indicate that ED LoS≥24 hours among admitted patients was associated with an increase in total IP LoS.*In the next 1-2 months, we intend to explore the role of other independent variables (age, sex, comorbidity, isolation status, and telemetry) on total ED LoS, and its association with IP LoS.

Improving nutritional practices in premature infants can increase their growth velocity and the breastfeeding rates.

This study analysed the changes in growth velocity (GV) of preterm infants weighing <1500 g based on different nutritional practices over a 24-year period. A retrospective study with prospectively collected data was performed in a level three Spanish neonatal intensive care unit. Data on birthweight, gestational age (GA) and GV were collected from 1990 to 2013 and breastfeeding data were gathered from 2000. A generalised linear model corrected by GA and small for gestational age was applied. Multiple mean comparisons between the levels of the variables of interest were performed using the Tukey test. We included 1651 children in the study. The average GA in 1990-1991 was 30.48 ± 2.89 and the average GA in 2012-2013 was 28.79 ± 2.58 (p < 0.01). Significant differences were found when we compared the adjusted GV between the first and last study periods. The most important differences appeared between 1990 and 2013, when the GV increased by 3.27 ± 0.5 g/kg/day (p < 0.01). The breastfeeding rate in 2000-2001 was 47.95% and in 2012-2013 it was 73.58% (p = 0.0002). Introducing nutritional practices such as the increased use of breastmilk and the breastfeeding rate improved GV over the study period.

Abstract P041: New Biomarkers for Detecting and Subtyping Insulin Resistance

Introduction: The metabolic abnormalities that precede type 2 diabetes progress slowly and in stages. Current evidence-based diabetes prevention programs target individuals in Stage 2 (impaired glucose tolerance or prediabetes). However, by that stage, 70% of pancreatic beta-cell insulin secretory capacity has been lost irreversibly. Thus, it is imperative to identify individuals in Stage I (early insulin resistance syndrome) in order to preserve pancreatic insulin secretion and prevent both diabetes and prediabetes. Early insulin resistance syndrome is characterized by compensatory hyperinsulinemia, dyslipidemia, sub-clinical inflammation and acid-base abnormalities. The nature of the association between these elements is unclear, and different subtypes of insulin resistance syndrome may exist. Hypothesis: We have developed two novel and unconventional biomarkers for characterizing insulin resistance in non-diabetic subjects. One approach is based on dynamic light scattering (DLS) of human serum. The second approach measures the T 2 relaxation time of water in human plasma using compact time-domain NMR relaxometry (TD-NMR). We hypothesize that these methods can detect subtypes, i.e. , insulin resistance with or without inflammation, hypercholesterolemia, or acid-base abnormalities. Methods: Seventy-two asymptomatic non-diabetic human subjects were recruited through an IRB-approved biomarker discovery protocol. Medical histories, anthropomorphic measurements and fasting blood samples were obtained, and over 1300 blood biomarkers were measured on each subject along with DLS and TD-NMR parameters. Bi-variate correlation analyses and multiple regression models were used to analyze continuous variables, and categorical variables were established for insulin resistance, inflammation, acid-base abnormalities and lipid abnormalities. Multiple means comparisons were performed using one-way ANOVA and Tukey-Kramer testing. Results: Plasma water T 2 from TD-NMR was strongly correlated with markers of early insulin resistance syndrome. Multiple regression analysis showed independent contributions from markers of hyperinsulinemia, hypercholesterolemia and inflammation. Multiple means comparisons showed significant differences for insulin resistance with and without inflammation. By contrast, DLS parameters were strongly correlated with insulin markers, but could not distinguish the inflammatory subtypes. Conclusions: Both TD-NMR and DLS are able to detect early insulin resistance in individuals who do not meet the criteria for prediabetes or metabolic syndrome. However, TD-NMR has the unique ability to distinguish inflammatory vs. non-inflammatory subtypes of insulin resistance. Subtyping and risk stratification are important for the design of personalized interventions to prevent diabetes, prediabetes and cardiovascular disease.

Field spectroscopy and radiative transfer modelling to assess impacts of petroleum pollution on biophysical and biochemical parameters of the Amazon rainforest

Biophysical and biochemical plant foliage parameters play a key role in assessing vegetation health. Those plant parameters determine the spectral reflectance and transmittance properties of vegetation; therefore, hyperspectral remote sensing, particularly imaging spectroscopy, can provide estimates of leaf and canopy chemical properties. Based on the relationship between spectral response and biochemical/biophysical properties of the leaves and canopies, the PROSPECT radiative transfer model simulates the interaction of light with leaves. In this study, more than 1100 leaf samples from the Amazon forest of Ecuador were collected at several study sites, some of which are affected by petroleum pollution, and across the vertical profile of the forest. For every sample, field spectroscopy at leaf level was conducted with a spectroradiometer. The goal of this study was to assess leaf optical properties of polluted and unpolluted rainforest canopies across the vertical profile and identify vegetation stress expressed in changes of biophysical and biochemical properties of vegetation. An ANOVA followed by Holme’s multiple comparisons of means and a principal component analysis showed that photosynthetic pigments, chlorophyll and carotenoids have significantly lower levels across the vertical profile of the forest, particularly in sites affected by petroleum pollution. On the other hand, foliar water content showed significantly higher levels in the polluted site. Those findings are symptoms of vegetation stress caused by reduced photosynthetic activity and consequently decreased transpiration and water-use efficiency of the plants. Cross-comparison between SPAD-502 chlorophyll content meter index and chlorophyll content showed strong positive correlation coefficients (r = 0.71 and r2 = 0.51) which suggests that using the SPAD-502 chlorophyll index itself is sensitive enough to detect vegetation stress in a multispecies tropical forest. Therefore, the SPAD-502 can be used to assess chlorophyll content of vegetation across polluted and non-polluted sites at different canopy layers. The results presented in this paper contribute to the very limited literature on field spectroscopy and radiative transfer models applied to the vertical profile of the Amazon forest.

Soporte técnico de simulación Phet en la enseñanza y aprendizaje de fracciones equivalentes

Este trabajo de investigación tuvo por objetivo comparar el resultado de cada estudiante con respecto a cada nivel de dificultad con la aplicación de Simulaciones Phet, en la enseñanza y el aprendizaje de fracciones equivalentes, fracciones mixtas y reducción de fracciones. Esta Investigación es de tipo experimental - cuantitativa, con un único grupo (Prueba con el simulador Phet). La población de estudio estuvo constituido por 40 estudiantes de octavo grado de educación secundaria de la Institución Educativa General Santander de Soacha-Cundinamarca. El grupo de estudio estuvo conformado por 40 estudiantes (20 hombres y 20 mujeres). Se realizó una comparación múltiple entre medias independientes, a partir del análisis estadístico de los datos aplicando la prueba Scheffé, se pudo observar que hay evidencia para rechazar la hipótesis nula, por tanto las medias son significativamente diferentes. La nota promedio fue 9,575 para el primer nivel, de 9,710 para el segundo nivel, de 9,385 para el tercer nivel, 8,840 para el cuarto nivel, 8,370 para el quinto nivel, 7,610 para el sexto nivel, 8,478 para el séptimo nivel, 7,530 para el octavo nivel. La aplicación del simulador Phet permitió un aprendizaje activo, participativo, característico, acrecentando el nivel de participación del estudiante, cumplimiento de tareas y actividades, y el interés por el tema de estudio, lo cual quedó demostrado.

153 SUPPLEMENTATION WITH LINOLENIC ACID AND L-CARNITINE DURING IVM REDUCED THE EXPRESSION OF GENES RELATED TO LIPOGENESIS BUT DID NOT ALTER THE LIPID CONTENT AND CRYOTOLERANCE OF IN VITRO-PRODUCED EMBRYOS

This study was conducted to evaluate the impact of supplementation during in vitro maturation (IVM) with linolenic acid (ALA), l-carnitine (L-car), or the combination of both supplements on the embryo intracellular lipid content and cryotolerance, as well as in the embryo expression of genes involved in lipid metabolism (lipogenesis regulation: SCD1, FASN, and SREBP1; and β-oxidation pathway: CPT1B and CPT2). Cumulus-oocyte complexes (n = 1076) were IVM for 22 h at 38.5°C and 5% CO2 in air, in TCM-199 medium with bicarbonate, hormones, and 10% FCS (control group), supplemented with 100 μM ALA (ALA group), 5 mM L-car (L-car group), or a combination of 100 μM ALA + 5 mM L-car (ALA + L-car group). After IVF, presumptive zygotes were in vitro cultured in SOFaa medium supplemented with 5 mg mL−1 BSA and 2.5% FCS, at 38.5°C and 5% CO2 in air during 7 days. Cleavage and blastocyst rates were evaluated on Day 3 and 7, respectively (IVF = Day 0). At Day 7, the blastocysts were stained with the lipophilic dye Sudan Black B (n = 60), vitrified/warmed (n = 260; Ingámed® protocol, Maringa-PR, Brazil), or collected for analysis of gene expression (n = 180). Embryonic development were analysed by ANOVA and the multiple comparisons of means were determined by Tukey’s test. The embryonic re-expansion data were subjected to chi-square test and the differences in gene expression among groups were evaluated by Duncan’s multiple range test (P &lt; 0.05). Data are presented as means ± standard error means. There was no effect (P &gt; 0.05) of the supplements used during IVM on cleavage (79.54 ± 2.76% to 82.16 ± 1.13%) and blastocyst rates (29.03 ± 3.07% to 30.46 ± 2.01%). Similarly, the intracellular lipid content in Day-7 blastocysts (1.03 ± 0.04 to 1.15 ± 0.07 pixels) and the embryonic cryotolerance, assessed by the re-expansion rates after 24 h (67.3 to 78.3%) hatching rates after 48 h (11.5 to 25.5%) of post-warming culture, were unaffected (P &gt; 0.05) by the supplements of IVM medium. Although the treatments did not alter (P &gt; 0.05) the expression of CPT1B and CPT2 genes, the expression of FASN gene was decreased (P &lt; 0.05) in the ALA group and the expression of SREBP1 gene was decreased (P &lt; 0.05) in the ALA and L-car groups. The expression of the gene SCD1 was reduced (P &lt; 0.05) in all treatments compared with the control group. Thus, despite the lack of effects of the treatments performed during IVM on the intracellular lipid content and cryotolerance of the embryos derived from the treated oocytes, a reduction in the expression of genes related to lipogenesis was observed in Day-7 blastocysts. These results suggest that treatments performed in the oocytes during IVM may have prolonged effects, affecting the subsequent expression of genes in embryos. Further studies are needed to determine the mechanisms related to the differentiation of the oocyte machinery during maturation. Financial support was provided by FAPESP (#2012/10084–4 and #2013/07382–6).

Chemical Scarification and Ozone in Seed Dormancy Alleviation of Wild and Domesticated Opuntia, Cactaceae

ABSTRACTProtocols for seed germination in the Opuntia genus are different and unsuitable for all their species. Dormancy of Opuntia seeds can be modified by the combination of scarification and an oxidizing agent such as O3, which could induce antioxidant and DNA-repair mechanisms or dormancy-breaking effects in hydrated seeds. The objective of this study was to evaluate the effects that the combination of mechanical and chemical scarification with exposition to sub-lethal O3 doses have on seed germination and seedling growth of O. streptacantha Lem., O. megacantha Salm-Dyck, and O. ficus-indica (L.) Mill. Our hypothesis was that O3 favors germination on scarified seeds and that the magnitude of the effect is species-dependent. Water uptake and germination were quantified in seeds every 48 h, until their roots reached a 5-mm length. The results were analyzed with an analysis of variance and multiple means comparisons with the Tukey test. Accelerated water uptake was observed during the first 48 h; the maximum average was 33.5% in all species. The combination of acid scarification and imbibition in the presence of O3 increased (P ≤ 0. 05) germination (between 17.8 and 44.4%), mainly in O. streptacantha. O3 increased germination, regardless of the species. O3 can be used in sublethal doses to increase seed germination and seedling development in Opuntia genus.

Effect of Plant Characteristics on Picking Efficiency of the Wild Blueberry Harvester

Abstract. Wild blueberry is a high value cash crop in northeastern North America. In the last two decades, improved management practices have changed crop characteristics. Currently, the wild blueberry industry is facing increased harvesting losses (15%-25%) due to changes in crop conditions. This study was designed to examine the effect of plant characteristics on picking efficiency of the wild blueberry harvester. Four wild blueberry fields were selected in Nova Scotia and New Brunswick, Atlantic Provinces of Canada. Plant height (PH) and plant density (PD) were classified into four different categories, i.e., tall plant - low plant density, tall plant - high plant density, short plant - low plant density, and short plant - high plant density, and stem thickness (ST) was used as a covariate. Nine yield plots (0.9 x 3 m) for each combination of PH and PD were selected randomly at each experimental field. The PH, PD, and ST were recorded manually from each selected plot. Factorial experiments with four replications were designed to identify the combined effect of ground speed (1.2, 1.6, and 2.0 km h-1) and header revolutions (26, 28, and 30 rpm) on berry losses at each category of PH and PD. Berry losses were collected from each plot within the selected fields. Factorial analysis of covariance (ANCOVA) using general linear model (GLM) procedure showed that the interaction of ground speed and header rpm was significant (p = 0.05) in each category of plant characteristics. Results of multiple means comparison showed that the lower ground speed and header rpm resulted in significantly lower losses when compared with higher ground speed and header rpm. The study findings also suggested a suitable combination of ground speed and header rpm for each class of plant characteristics to minimize the berry losses during harvesting.

Sensory evaluation of beef and buffalo extensively reared and its relationship to sociodemographic characteristics of consumers

Sensory characteristics of meat from different animal types, including cattle (Angus and Brangus) and buffalo raised at pasture, and information on socio-demographic determinants of consumer preference were evaluated. Samples of roasted rib eye were cut and served in a disordered and monadic manner to 188 untrained tasters. A nine-point hedonic scale was used to assess odor, color, tenderness, succulence and overall appearance. Analysis of variance was carried out using the GLM procedure of SAS®, considering animal type and socio-demographic characteristics as fixed effects and using the LSMEANS procedure for multiple mean comparisons. Differences (P &amp;lt; 0.001) between animal types were observed only for tenderness, with Brangus (7.02) and buffalo (6.82) meat being superior to Angus (6.25). Regardless of meat origin, age, income, smoking and place of purchase affected the perceived attributes (P &amp;lt; 0.05). People aged over 50 years gave higher mean scores for odor and color (P &amp;lt; 0.05), indicative of greater satisfaction and less demanding tastes when compared to other age categories. Despite the variability in the intrinsic characteristics, differentiation of meat by the consumer is not easy to determine, with little impact of sociodemographic characteristics on organoleptic perception. Meat from Brangus cattle and buffaloes raised at pasture was considered tenderer than that from Angus cattle raised under the same conditions by an untrained taste panel compared with.