scholarly journals Differential Foraging of Indigenous and Exotic Honeybee (Apis mellifera L.) Races on Nectar-Rich Flow in a Subtropical Ecosystem

Insects ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 254
Author(s):  
Abdulaziz S. Alqarni
Keyword(s):  
Apis Mellifera ◽  
Weather Conditions ◽  
Field Trips ◽  
Negative Effects ◽  
Adverse Weather Conditions ◽  
Apis Mellifera Jemenitica ◽  
Adverse Weather ◽  
Windy Weather ◽  
Honeybee Subspecies ◽  
Bee Colonies

In the subtropics, agricultural activities such as beekeeping are greatly influenced by environmental challenges. In the desert of Central Arabia, honeybees forage on limited prairies that are affected by adverse weather conditions. Bee colonies reduce their field activities during extremely hot-dry-windy weather. This study investigated whether nectar-rich melliferous flora enhance the field activities of two honeybee subspecies, Apis mellifera jemenitica (indigenous) and A. m. carnica (exotic), despite the presence of severe weather conditions. The foraging and pollen-gathering activities of the two subspecies were evaluated on Acacia trees (Acacia gerrardii Benth.), a common subtropical, summery endemic bee plant, in the central desert of the Arabian Peninsula. The native colonies were significantly (p < 0.001) more active foragers than the exotic colonies (109 ± 4 and 49 ± 2 workers/colony/3 min, respectively). Similarly, the native colonies recruited significantly (p ˂ 0.01) more active pollen-gathering bees than the imported colonies (22 ± 1 and 7 ± 1 workers/colony/3 min, respectively). Furthermore, far more food was collected by the indigenous colonies than by the exotic colonies, and a higher portion of all field trips was allocated to pollen gathering by the indigenous bees than by the imported bees. The nectar-rich Acacia trees reduced the negative effects of hot-dry-windy weather. More research on honeybee colonies operating in the subtropical conditions of Central Arabia is needed, especially regarding heat tolerance mechanisms and effects on queen and drone fertility.

scholarly journals Barreiras percebidas à prática de atividades físicas em escolares do ensino médio

2016 ◽  
Vol 18 (5) ◽  
pp. 567 ◽  
Author(s):  
Kelly Christine Maccarini Pandolfo ◽  
Tatiane Minuzzi ◽  
Rafaella Righes Machado ◽  
Luís Felipe Dias Lopes ◽  
Cati Reckelberg Azambuja ◽  
...  
Keyword(s):  
High School ◽  
High School Students ◽  
Weather Conditions ◽  
Public High School ◽  
Negative Effects ◽  
School Students ◽  
Chi Square ◽  
Adverse Weather Conditions ◽  
Adverse Weather ◽  
The Difference

DOI: http://dx.doi.org/10.5007/1980-0037.2016v18n5p567 In an attempt to understand the problem of declining physical activity (PA) among adolescents, there has been an increasing interest in identifying perceived barriers (PB) that can reduce the involvement of adolescents in PA. The aim of this study was to identify PB to PA practice among public high school students. The samples was composed of 348 students aged 14-19 years, 46.8% females and 53.2% males. To investigate BP, an instrument consisting of 12 statements and validated for the study population was used. The analysis of results was carried out by descriptive statistics, Kruskal Wallis test to check the possible differences in PB throughout high school years and chi-square for the difference in proportions of barriers. Having many tasks to do, lack of time and adverse weather conditions were the most cited PB. There was no difference in the perception of barriers among high school years (males: p = 0.44; females: p = 0.23). PB “not having how to go or return” (p = 0.04), “adverse weather conditions” and “laziness” (p = 0.02), “lack of time” (p = 0.01) and “at home nobody performs PA” (p = 0.04) showed statistically significant differences between sexes. Both sexes reported similar barriers; however, girls reported higher number of PB and with greater frequency. Identifying which PB prevent the adoption of a physically active lifestyle may be the beginning of solutions to minimize the negative effects.

scholarly journals Ship Handling in Unprotected Waters: A Review of New Technologies in Escort Tugs to Improve Safety

2021 ◽  
Vol 2 (1) ◽  
pp. 46-62
Author(s):  
Santiago Iglesias-Baniela ◽  
Juan Vinagre-Ríos ◽  
José M. Pérez-Canosa
Keyword(s):  
High Performance ◽  
New Technologies ◽  
Weather Conditions ◽  
Hull Form ◽  
Best Available Technologies ◽  
Adverse Weather Conditions ◽  
Adverse Weather ◽  
New Type ◽  
Technological Challenge ◽  
And Performance

It is a well-known fact that the 1989 Exxon Valdez disaster caused the escort towing of laden tankers in many coastal areas of the world to become compulsory. In order to implement a new type of escort towing, specially designed to be employed in very adverse weather conditions, considerable changes in the hull form of escort tugs had to be made to improve their stability and performance. Since traditional winch and ropes technologies were only effective in calm waters, tugs had to be fitted with new devices. These improvements allowed the remodeled tugs to counterbalance the strong forces generated by the maneuvers in open waters. The aim of this paper is to perform a comprehensive literature review of the new high-performance automatic dynamic winches. Furthermore, a thorough analysis of the best available technologies regarding towline, essential to properly exploit the new winches, will be carried out. Through this review, the way in which the escort towing industry has faced this technological challenge is shown.

Statistical analysis and critical review of navigational accidents in adverse weather conditions

2018 ◽  
Vol 163 ◽  
pp. 502-517 ◽  
Author(s):  
N.P. Ventikos ◽  
A.D. Papanikolaou ◽  
K. Louzis ◽  
A. Koimtzoglou
Keyword(s):  
Statistical Analysis ◽  
Critical Review ◽  
Weather Conditions ◽  
Adverse Weather Conditions ◽  
Adverse Weather

Gendered Experiences of Mobility

Transfers ◽  
2013 ◽  
Vol 3 (3) ◽  
pp. 79-98 ◽  
Author(s):  
Shahnaz Huq-Hussain ◽  
Umme Habiba
Keyword(s):  
Middle Class ◽  
Travel Behavior ◽  
Weather Conditions ◽  
Capital City ◽  
Mobility Patterns ◽  
Security Issues ◽  
Adverse Weather Conditions ◽  
Adverse Weather ◽  
The City ◽  
Detailed Picture

This article examines the travel behavior of middle-class women in Dhaka, the capital city of Bangladesh and one of the world's largest and most densely populated cities. In particular, we focus on women's use of non-motorized rickshaws to understand the constraints on mobility for women in Dhaka. Primary research, in the form of an empirical study that surveyed women in six neighborhoods of Dhaka, underpins our findings. Our quantitative and qualitative data presents a detailed picture of women's mobility through the city. We argue that although over 75 percent of women surveyed chose the rickshaw as their main vehicle for travel, they did so within a complex framework of limited transport options. Women's mobility patterns have been further complicated by government action to decrease congestion by banning rickshaws from major roads in the city. Our article highlights the constraints on mobility that middle-class women in Dhaka face including inadequate services, poorly maintained roads, adverse weather conditions, safety and security issues, and the difficulty of confronting traditional views of women in public arenas.

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