Length-weight Relationships and Condition Factor of Parachanna Obscura Gunther 1861 in Epe Lagoon, Lagos, Nigeria

Background: The study of the length-weight relationship (LWR) and condition factor (K) are critical in fisheries research and management. However, there is currently a dearth of information on the growth pattern and state of health of Parachanna obscura in Epe lagoon Methods: A total of 252 species of P. obscura ranging from 19.50 to 36.70 cm (standard length = 28.22 ± 4.95 cm) and 58.80 to 331.00 g (total weight = 267.69 ± 72.16 g) were obtained from the catches of local fishermen at the chief market fish landing station monthly for six months (January – June, 2018) at Epe lagoon, Lagos, Nigeria. Standard Length (SL) and Body Weight (BW) were measured to the nearest 0.1 cm and 0.01 g using digital Vernier calliper and electronic precision balance, respectively. Length-Weight Relationships and condition factor (K) were calculated using standard formula. Data were analysed using descriptive statistics and ANOVA at α 0.05. Results: The LWRs for males, females and combined sexes were 2.60, 2.70, and 2.65, respectively, indicating a negative allometric growth pattern. The mean K value in females (1.36±0.70) was higher than in males (1.18±0.48). Conclusion: The findings indicated that Parachanna obscura in Epe lagoon, Nigeria were heavy and in good health within the study period

SEASONALITY IN LITTERFALL PRODUCTION IN A NATIVE FOREST IN THE CENTRAL REGION OF RS, BRAZIL

Studies on litter deposition are considered an important indicator of environmental quality of forest ecosystems. It is the main route of entry of organic matter and nutrients to forests. The objective of this study was to quantify the annual litterfall and seasonality in a fragment of native forest located in São Sepé in the Central Depression of Rio Grande do Sul. The experiment was conducted in a fragment of a Seasonal Semideciduous Forest. Inside this forest, in a place with homogeneous conditions, five plots of 20 m x 15 m length were systematically allocated 30 meters away from each other, where five litterfall traps were distributed in each plot (0,1963 m2 each trap), totaling 25 traps. The collection of all plant material deposited by the trees in the collectors was performed monthly in a four-year period. In the laboratory, the samples were separated into leaves, small twigs (diameter < 0.5 cm) and miscellaneous, and after they were oven dried and weighed on a precision balance. Higher litterfall was observed in the spring, with the highest return peaks mainly in October, indicating a seasonal deposition behavior. The mean litterfall was 6.56 Mg ha-1 year-1; of this total, the leaves were responsible for 67.61%, followed by the miscellaneous with 19.04% and the small twigs with 13.29%. Only a high significant correlation was obtained between the miscellaneous fraction and the temperature.

Open-Source Digitally Replicable Lab-Grade Scales

This study provides designs for a low-cost, easily replicable open-source lab-grade digital scale that can be used as a precision balance. The design is such that it can be manufactured for use in most labs throughout the world with open-source RepRap-class material extrusion-based 3-D printers for the mechanical components and readily available open-source electronics including the Arduino Nano. Several versions of the design were fabricated and tested for precision and accuracy for a range of load cells. The results showed the open-source scale was found to be repeatable within 0.05 g with multiple load cells, with even better precision (0.005 g) depending on load cell range and style. The scale tracks linearly with proprietary lab-grade scales, meeting the performance specified in the load cell data sheets, indicating that it is accurate across the range of the load cell installed. The smallest load cell tested (100 g) offers precision on the order of a commercial digital mass balance. The scale can be produced at significant cost savings compared to scales of comparable range and precision when serial capability is present. The cost savings increase significantly as the range of the scale increases and are particularly well-suited for resource-constrained medical and scientific facilities.

Open Source Digitally Replicable Lab-Grade Scales

This study provides designs for a low-cost, easily replicable open source lab-grade digital scale that can be used as a precision balance. The design is such that it can be manufactured for use in most labs throughout the world with open source RepRap-class material extrusion-based 3-D printers for the mechanical components and readily available open source electronics including the Arduino Nano. Several versions of the design were fabricated and tested for precision and accuracy for a range of load cells. The results showed the open source scale was found to be repeatable within 0.1g with multiple load cells, with even better precision (0.01g) depending on load cell range and style. The scale tracks linearly with proprietary lab-grade scales, meeting the performance specified in the load cell data sheets, indicating that it is accurate across the range of the load cell installed. The smallest loadcell tested(100g) offers precision on the order of a commercial digital mass balance. The scale can be produced at significant cost savings compared to scales of comparable range and precision when serial capability is present. The cost savings increase significantly as the range of the scale increases and are particularly well-suited for resource-constrained medical and scientific facilities.

Calcium phosphate influences erosivity of non alcoholic beverages in vitro

Background: The effect of added calcium phosphate to non alcoholic beverages to reduce erosivity on bovine enamel and dentine was analyzed. Methods: 90 enamel and 90 dentine specimens from freshly extracted bovine incisors were randomly attributed to 9 enamel and 9 dentine groups (n=10 each). Initially, all specimens were weighted using a precision balance. They were suspended in plastic bottles containing 150ml of the following beverages: Cola, orange juice, Red Bull, Bonaqua Fruits. To all beverages 100mg (c1) or 200mg (c2) calcium hydrogen phosphate dihydrate was added. Tap water served as control. After 7 days, median mass loss was calculated in mg. Kruskal-Wallis and Mann-Whitney u-test served for comparison between groups. Results: Cola and Bonaqua Fruits lost erosivity already after addition of 100mg calcium phosphate. Red Bull after 100mg on enamel and 200mg on dentine. Only orange juice remained erosive on dentine and enamel even after the addition of 200mg calcium phosphate. Conclusion: The addition of calcium phosphate may reduce or even prevent the erosivity of some highly erosive non alcoholic beverages on bovine enamel and dentine.

Effect of Post Emergent Herbicides on Centaurea diluta Aiton Infecting Wheat in Ouazzane Region - Morocco

High infestations of Centaurea diluta (Lesser star-thistle) become a serious problem to cereal farmers in Ouazzane region of Morocco. The aim of this study is to investigate the effect of three post-emergent herbicides on C. diluta infestation in a soft wheat crop. The experimental design was Randomized Complete Block Design (RCBD) with three replications. Each block contained 4 elementary plots, 3 plots of which were treated with the three post emergent herbicides and the untreated plots serving as control. Trials were conducted in Ouazzane region of Morocco in January 2017. Treatments were carried out with a knapsack sprayer with the nozzle delivering a 3 bar jet. Calculation of reduction of biomass in C. diluta was carried out at weed research laboratory of INRA-CRRA Tangier in March 2017 using an oven at 75ºC for 48 hours. The weights were then taken using a precision balance. A quadrant of 1 m2 was used to calculate the reduction of density in C. diluta. Results showed that treatment with Aminopyralid + Florasulam at (9.9 + 4.95) g/ha and 2,4-D at 600 g/ha gave the best control of C. diluta infestations. In fact, Aminopyralid + Florasulam at (9.9+4.95) g/ha recorded 88±4.1%, 86±5.1% and 97±1.6% respectively on reduction of density, height and biomass in C. diluta. 2,4-D at 600 g/ha recorded 75±3.1%, 84±4.2% and 94±2.5% respectively on reduction of density, height and biomass in C. diluta. Tribenuron-methyl at 9.50 g/ha recorded the lowest efficacies recording 25±4.9%, 21±4.8% and 37±8.1% respectively on reduction of density, height and biomass in C. diluta. Thus, Aminopyralid + Florasulam at (9.9+4.95) g/ha and 2,4-D at 600 g/ha could be recommended to farmers in Ouazzane region when C. diluta infestation is dominant on wheat. A further assessment of Aminipyralid and Florasulam residues in soil and their phytotoxicities should be evaluated on other crops grown in rotations.

Effect of Florasulam and 2,4-D on Fineleaf Fumitory (Fumaria parviflora Lam.) Infestation in Wheat Crop

Aims: High infestations of Fumaria parviflora (Fineleaf fumitory) may led to cereal crops yield reduction. The aim of this study is to investigate the effect of mixture of Florasulam and 2,4-D on F. parviflora infestation in a soft wheat crop. Study Design: The experimental design was Randomized Complete Block Design (RCBD) with three replications. Each block contained 4 elementary plots, 3 plots of which were treated with three rates of application of mixture of Florasulam and 2.4-D and one untreated control plot. Place and Duration of Study: Trials were conducted in Ouazzane region of Morocco in January 2017. Calculation of dry F. parviflora biomass was carried out at weed research laboratory of INRA-CRRA Tangier in March 2017. Methodology: Treatments were carried out with a knapsack sprayer with the nozzle delivering a 3 bar jet. A quadrant of 1 m x 1 m was used to calculate percentage of F. parviflora density reduction, height reduction and biomass reduction. F. parviflora dry biomass were determined using an oven at 75ºC for 48 hours. Then, weighed with a precision balance. Results: Treatment with mixture of Florasulam and 2,4-D respectively at 5.63 and 270 g/ha gave the best control of F. parviflora infestations. In fact, “Florasulam+2,4-D” at (5.63+270) g/ha recorded 85±3.1%, 81±2.5% and 92±3.1% respectively on F. parviflora density reduction, F. parviflora height reduction and F. parviflora dry biomass reduction. “Florasulam+2,4-D” at (3.75 +180) g/ha recorded 66±5.3%, 63±4.7% and 74±2.6% respectively on F. parviflora density reduction, F. parviflora height reduction and F. parviflora dry biomass reduction. Florasulam + 2,4-D at (1.88+90) g/ha recorded the lowest efficacies 45±10.4%, 22±9.5% and 45±11.4% respectively on F. parviflora density reduction, F. parviflora height reduction and F. parviflora dry biomass reduction. Conclusion: «Florasulam+2,4-D» at (5.63+270) g/ha could be recommended to farmers in Ouazzane region when F. parviflora infestation is dominant on wheat. A further assessment of «Florasulam+2,4-D» residues in soils and their phytotoxicities should be evaluated on other crops grown in rotations.

Formation Mechanism of Aluminide Diffusion Coatings on Ti and Ti-6Al-4V Alloy at the Early Stages of Deposition by Pack Cementation

The diffusion coatings were deposited on commercially pure Ti and Ti-6Al-4V alloy at up to 1000 °C for up to 10 h using the pack cementation method. The pack powders consisted of 4 wt% Al (Al reservoir) and 4 wt% NH4Cl (activator) which were balanced with Al2O3 (inert filler). The growth kinetics of coatings were gravimetrically measured by a high precision balance. The aluminised specimens were characterised by means of scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). At the early stages of deposition, a TiO2 (rutile) scale, other than aluminide coating, was developed on both materials at <900 °C. As the experimental temperature arose above 900 °C, the rutile layer became unstable and reduced to the low oxidation state of Ti oxides. When the temperature increased to 1000 °C, the TiO2 scale dissociated almost completely and the aluminide coating began to develop. After a triple-layered coating was generated, the coating growth was governed by the outward migration of Ti species from the substrates and obeyed the parabolic law. The coating formed consisted of an outer layer of Al3Ti, a mid-layer of Al2Ti and an inner layer of AlTi. The outer layer of Al3Ti dominated the thickness of the aluminide coating.

INFLUENCE OF OBESITY ON SCHOOLGIRLS MOTOR SKILL PERFORMANCE

The aim of this study is to compare the motor skills status of girls with different nutritional status. The research sample consisted of 180 girls aged 10 and was divided into 4 subsamples: malnourished, normally nourished, pre-obese and obese girls. The assessment of the motor space was carried out with a battery of eighteen motor tests. The identification of the differences between the groups was carried out by the Univariate Analysis of Variance (ANOVA) method. The significance of the differences between the groups was tested by the Multivariate Analysis of Variance (MANOVA) method. The results of the study suggest that obese girls had problems in variables which assessed the explosive power of the lower extremities, running speed and repetitive strength. No significant differences were found for variables which evaluate segmental speed, flexibility, precision, balance, cranial body muscle explosion, and coordination.

Coating effect of micro-sized droplets impacting on low temperature spherical particles

In this paper, the effect of spray droplets on the coating of cold spherical particles was studied.The microcapsule granulator produces micron-sized droplets to coat the spherical particles in cold storage, and the high-definition camera and precision balance are used to photograph and weigh the particles before and after the spraying. The droplets are obtained by using the image and data processing technology coating area and coating quality, the droplet coating effect was evaluated by a number of dimensionless parameters such as coating ratio and mass ratio.By orthogonal design experiment and uncertainty analysis, the effects of droplet size and flow rate, spherical particle temperature and diameter on coating effect were studied, and the effect of droplet group coating on low temperature spherical particles was obtained. Keywords: Spray freeze drying; Droplets; Coating; Spherical particles.