scholarly journals Extreme Effects of Season on the Foraging Activities and Colony Productivity of a Stingless Bee (Melipona asilvaiMoure, 1971) in Northeast Brazil

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Daniela Lima do Nascimento ◽  
Fabio Santos Nascimento
Keyword(s):  
Atlantic Forest ◽  
Stingless Bee ◽  
Forest Area ◽  
Northeast Brazil ◽  
Rainy Period ◽  
Video Cameras ◽  
Factors Influencing ◽  
Temperature And Humidity ◽  
Main Factors ◽  
Colony Productivity

This study reports the influence of season on foraging activities and internal colonial parameters ofMelipona asilvaiin an Atlantic forest area of northeast Brazil. We used video cameras connected to a PC to monitor all departures and returns of foragers and the types of materials they carried. Foraging activities decreased almost 90% from dry to rainy seasons, but temperature and humidity were not the main factors influencing departures. Observed honey storage and an extreme cutback in activities during the rainy period suggest a seasonal diapause in this species.

scholarly journals N:Si:P atomic ratio in the Santa Cruz Channel, Itamaracá-PE (Northeast Brazil): a nyctemeral variation

2002 ◽  
Vol 45 (2) ◽  
pp. 115-124 ◽  
Author(s):  
Manuel de Jesús Flores Montes ◽  
Silvio José de Macêdo ◽  
Maria Luise Koening
Keyword(s):  
Rainy Season ◽  
Meteorological Parameters ◽  
Atomic Ratio ◽  
Northeast Brazil ◽  
Santa Cruz ◽  
Factors Influencing ◽  
Nitrate N ◽  
Physical Chemical ◽  
Dry Seasons ◽  
Main Factors

Studies were carried out on the Inlets of Orange and Catuama at the Santa Cruz Channel, Itamaracá-PE, in the rainy and dry seasons, in a nyctemeral cycle, and in a transversal profile, with intervals of three hours between collections. The objective was to determine the spacial and temporal variation of the N:Si:P atomic ratio, and its possible inter-relations and dependencies, as well as the influence of the hydrodynamism provoked by the variation of the tides at different times of the year. Nitrite-N and nitrate-N were higher in the rainy season, while ammonia-N, phosphate-P and silicate-Si were higher in the dry season, which indicated different results than previous studies. The N:P atomic ratio was lower than 16:1, in all seasons and stations, being highest in the rainy season at Inlet Orange. The Si:P atomic ratio was always high. During the observed nyctemeral cycles, the main factors influencing the composition of the physical, chemical and biological parameters were the tide cycles and the meteorological parameters.

Reproduction potential-based differentiation of Russian regions

2020 ◽  
Vol 18 (7) ◽  
pp. 1304-1319
Author(s):  
M.V. Moroshkina
Keyword(s):  
Spatial Development ◽  
Uneven Development ◽  
Regional Differentiation ◽  
Russian Regions ◽  
Policy Documents ◽  
Factors Influencing ◽  
Strategic Policy ◽  
Main Factors ◽  
Per Capita ◽  
Research Period

Subject. This article examines the issues related to changes in reproduction capacity and heterogeneity of the development of Russian regions. Objectives. The article aims to assess regional differentiation and investigate the main factors influencing the uneven development of the areas. Methods. For the study, we used the methods of comparative and correlation analyses. Results. The article identifies groups of leading and lagging Russian regions and assesses the possibility of convergence of Russian regions according to the analyzed indicators, such as GRP, GRP per capita, and the output of industry. Conclusions. The results obtained can be used when preparing strategic policy documents, spatial development programmes and concepts. The observed heterogeneity suggests that the regions maintain their positions throughout the research period.

Polymer composites as sensing materials for liquid organic solvents – preliminary results

e-Polymers ◽  
2011 ◽  
Vol 11 (1) ◽  
Author(s):  
Stanislaw Frackowiak ◽  
Monika Maciejewska ◽  
Andrzej Szczurek ◽  
Marek Kozlowski
Keyword(s):  
Electrical Resistivity ◽  
Carbon Black ◽  
Polymer Composites ◽  
Percolation Theory ◽  
Liquid Mixtures ◽  
Organic Liquids ◽  
Volumetric Fraction ◽  
Factors Influencing ◽  
Benzene Toluene ◽  
Main Factors

AbstractCarbon black-filled polymer composites were investigated as sensing materials for organic liquids. Polypropylene and polystyrene which were selected as matrices and various amounts of carbon black were considered as the main factors influencing sensitivity of the composites in view of the percolation theory. Disposable filaments were produced of these materials. Change in their electrical resistivity was measured upon immersion in benzene, toluene, xylene, ethylbenzene and their mixtures. It has been found that studied materials were sensitive to the composition of liquid mixtures of organic solvent. Relationships between the filament response and volumetric fraction of the components were presented. The studied materials have shown promising sensing properties, which suggest their applicability for identification and quantification of multicomponent organic liquids.

Do vegetal communities dominated by invasive exotic plant species affect the structure of bird communities in an Atlantic Forest area?

2020 ◽  
Vol 28 (4) ◽  
pp. 241-249
Author(s):  
Cleverton da Silva ◽  
Arleu Barbosa Viana-Junior ◽  
Cristiano Schetini de Azevedo ◽  
Juliano Ricardo Fabricante
Keyword(s):  
Plant Species ◽  
Atlantic Forest ◽  
Bird Communities ◽  
Forest Area ◽  
Exotic Plant ◽  
Exotic Plant Species ◽  
Invasive Exotic

Factors Influencing Saudi Parents’ Choice of International Schools in Saudi Arabia

2020 ◽  
Vol 19 (3) ◽  
pp. 220-232
Author(s):  
Hamdah Abdullah Alfaraidy
Keyword(s):  
Socioeconomic Status ◽  
International Education ◽  
School Quality ◽  
International Schools ◽  
Traditional Schools ◽  
Ministry Of Education ◽  
Public And Private ◽  
Mandated Curriculum ◽  
Factors Influencing ◽  
Main Factors

The Saudi Ministry of Education has recently begun to allow all Saudi families to enroll their children in international schools. The international curriculum offered by such schools represents a notably different choice compared with Saudi traditional public and private schools, both of which teach the same state-mandated curriculum. As a result of the change, there has been a surge in demand for international education; the number of schools has increased rapidly, and there has been a steady “student leak” towards them and away from traditional schools. Little is known about why Saudi parents choose to enroll their children in international schools. We explored this question by surveying 431 Saudi parents of children attending such schools to identify the main factors contributing to their choice. Although all factors examined were important to parents, curriculum and overall school quality emerged as the most important; socioeconomic status was not influential in their decisions.

scholarly journals Implementation Constraints on Israel–Palestine Water Cooperation: An Analysis Using the Water Governance Assessment Framework

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 620
Author(s):  
Liping Dai
Keyword(s):  
Water Governance ◽  
Political Environment ◽  
Assessment Framework ◽  
Foreseeable Future ◽  
Current Technology ◽  
Factors Influencing ◽  
Water Cooperation ◽  
Main Factors ◽  
Enforcement Mechanisms ◽  
Business As Usual

This study uses a diagnostic and multidisciplinary water governance assessment framework to examine the main factors influencing water cooperation on the shared Mountain Aquifer between Israel and Palestine. It finds that effective cooperation between Israel and Palestine is unlikely in the foreseeable future if both parties persist with the business-as-usual approach. What constrains the two parties from achieving consensual agreement are political tensions, the constraints of current technology, the different perceptions of the value of the shared water, the mistrust between the two parties, the lack of external enforcement mechanisms, and the impacts of the domestic political environment.

scholarly journals Determining the Main Factors Influencing the Energy Consumption of Electric Vehicles in the Usage Phase

Procedia CIRP ◽  
2016 ◽  
Vol 48 ◽  
pp. 352-357 ◽  
Author(s):  
Wen Li ◽  
Patrick Stanula ◽  
Patricia Egede ◽  
Sami Kara ◽  
Christoph Herrmann
Keyword(s):  
Energy Consumption ◽  
Electric Vehicles ◽  
Usage Phase ◽  
Factors Influencing ◽  
Main Factors

The Use of Sol-Gel Method for Obtaining Fire-Resistant Elastic Coatings on Cotton Fabrics

2021 ◽  
Vol 1038 ◽  
pp. 468-479
Author(s):  
Olga Skorodumova ◽  
Olena Tarakhno ◽  
Olena Chebotaryova ◽  
Oleg Bezuglov ◽  
Fatih Mehmet Emen
Keyword(s):  
Thin Layer ◽  
Fire Protection ◽  
Sol Gel ◽  
Fire Retardant ◽  
Cotton Fabrics ◽  
Covalent Bonds ◽  
Silica Coatings ◽  
Factors Influencing ◽  
Fire Retardant Properties ◽  
Main Factors

Based on the generalization of research results on the processes of obtaining SiO2 sols using tetraethoxysilane and ethyl silicates, the main factors influencing the elasticity of silica coatings on cotton fabrics and their fire-retardant properties are considered. The possibility of forming covalent bonds between the functional groups of cellulose, gel coating and flame retardant layer is considered, which explains the strong fixation of a thin layer of coating on the fibers of the fabric and improve its fire protection. The use of the developed compositions for fire-retardant elastic coatings based on ethyl silicate allows to increase the time of complete burning of cotton from 30s (untreated fabric) to 600s (treated with binary coating).

Investigation of the SHS Process Initiation in Base Mixture during HFC-Heating and the Combustion Rate Dependence on Various Factors

2021 ◽  
Vol 1031 ◽  
pp. 67-74
Author(s):  
Alexey V. Ishkov ◽  
Vladimir N. Malikov ◽  
Alexander Shegolev
Keyword(s):  
Combustion Rate ◽  
Coating Layer ◽  
Thin Layers ◽  
Powder Materials ◽  
Charge Composition ◽  
Powder Mixtures ◽  
Factors Influencing ◽  
Main Factors ◽  
Ignition And Combustion ◽  
Coating Layer Thickness

The paper describes the researches of the SHS process initiation in samples of powder mixtures of reagents intended for steel parts hardening with an excess of Al or B2O3 by a heat source. Mixtures of reagents with different weight ratios of components were used as samples. Thereat, the initiation of SHS process in thin layers was conducted with a coating layer thickness of no more than 6 mm for all tested compositions. The dependences of the combustion rate on various factors including particle size of powder materials and charge composition have been obtained. The main factors influencing the dependences of initiation (ignition) and combustion rate are established, and the degree of influence of these factors on the dependences is estimated. The obtained results made it possible to correct the composition of the base mixture reasonably in order to achieve the required combustion rate.

Sign in / Sign up

Export Citation Format

Share Document