scholarly journals Path tortuosity changes the transport cost paradigm in terrestrial animals

Ecography ◽  
2021 ◽  
Author(s):  
Rory P. Wilson ◽  
Kayleigh A. R. Rose ◽  
Richard S. Metcalfe ◽  
Mark D. Holton ◽  
James Redcliffe ◽  
...  
Keyword(s):  
Transport Cost ◽  
Path Tortuosity

scholarly journals Path tortuosity changes the transport cost paradigm in terrestrial animals

2020 ◽  
Author(s):  
R. P. Wilson ◽  
K. A. R. Rose ◽  
R. S. Metcalfe ◽  
M. D. Holton ◽  
J. Redcliffe ◽  
...  
Keyword(s):  
Animal Movement ◽  
Transport Cost ◽  
Movement Speed ◽  
Maximum Speed ◽  
Cost Of Transport ◽  
Environment And Behavior ◽  
Full Speed ◽  
Path Tortuosity ◽  
And Behavior ◽  
Free Ranging

AbstractAnimal movement paths are variously tortuous, with high turn rates predicted to be energetically costly, especially at high speeds. Animals travel most efficiently at the speed that gives the lowest cost of transport (COT), a well-defined point for movement in fluid media. However, theoretically, land animals should travel at their maximum speed to minimize COT, which they do not, instead travelling at walking pace. We measured oxygen consumption in humans to demonstrate that the energetic costs of turning increase disproportionately with both speed and angular velocity. This resulted in the minimum COT speed occurring at very low speeds, which reduced with increased path tortuosity. Data on turn rates from six free-ranging terrestrial species underpinned this because all individuals turned faster at the slowest speeds across the full speed range. The optimum movement speed for minimum COT in land animals thus depends on the environment and behavior since both affect track tortuosity.

scholarly journals Transport Cost Estimation Model of the Agroforestry Biomass in a Small-Scale Energy Chain

2020 ◽  
Vol 3 (1) ◽  
pp. 22
Author(s):  
Giulio Sperandio ◽  
Andrea Acampora ◽  
Vincenzo Civitarese ◽  
Sofia Bajocco ◽  
Marco Bascietto
Keyword(s):  
Supply Chain ◽  
Power Plant ◽  
Central Italy ◽  
Biomass Energy ◽  
Transport Cost ◽  
Small Scale ◽  
Economic Sustainability ◽  
Transport Costs ◽  
Energy Chain ◽  
Biomass Power Plant

The delivery of biomass products from the production place to the point of final use is of fundamental importance within the constitution of energy chains based on biomass use as renewable energy source. In fact, transport can be one of the most economically expensive operations of the entire biomass energy production process. In this work, a geographic identification, through remote sensing and photo-interpretation, of the different biomass sources was used to estimate the potential available biomass for energy in a small-scale supply chain. The economic sustainability of transport costs was calculated for different types of biomass sources available close to a biomass power plant of a small-scale energy supply chain, in central Italy. The proposed analysis allows us to highlight and visualize on the map the areas of the territory characterized by greater economic sustainability in terms of lower transport costs of residual agroforestry biomass from the collection point to the final point identified with the biomass power plant. The higher transport cost was around € 40 Mg−1, compared to the lowest of € 12 Mg−1.

scholarly journals Understanding health-seeking and adherence to treatment by patients with esophageal cancer at the Uganda cancer Institute: a qualitative study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Nakimuli Esther ◽  
Ssentongo Julius ◽  
Mwaka Amos Deogratius
Keyword(s):  
Esophageal Cancer ◽  
Data Collection ◽  
Qualitative Study ◽  
Cancer Patients ◽  
Healthcare Professionals ◽  
Transport Cost ◽  
Adherence To Treatment ◽  
Health Seeking ◽  
Long Distance ◽  
Cancer Symptoms

Abstract Background In the low- and middle-income countries, most patients with esophageal cancer present with advanced stage disease and experience poor survival. There is inadequate understanding of the factors that influence decisions to and actual health-seeking, and adherence to treatment regimens among esophageal cancer patients in Uganda, yet this knowledge is critical in informing interventions to promote prompt health-seeking, diagnosis at early stage and access to appropriate cancer therapy to improve survival. We explored health-seeking experiences and adherence to treatment among esophageal cancer patients attending the Uganda Cancer Institute. Methods We conducted an interview based qualitative study at the Uganda Cancer Institute (UCI). Participants included patients with established histology diagnosis of esophageal cancer and healthcare professionals involved in the care of these patients. We used purposive sampling approach to select study participants. In-depth and key informant interviews were used in data collection. Data collection was conducted till point of data saturation was reached. Thematic content analysis approach was used in data analyses and interpretations. Themes and subthemes were identified deductively. Results Sixteen patients and 17 healthcare professionals were included in the study. Delayed health-seeking and poor adherence to treatment were related to (i) emotional and psychosocial factors including stress of cancer diagnosis, stigma related to esophageal cancer symptoms, and fear of loss of jobs and livelihood, (ii) limited knowledge and recognition of esophageal cancer symptoms by both patients and primary healthcare professionals, and (iii) limited access to specialized cancer care, mainly because of long distance to the facility and associated high transport cost. Patients were generally enthused with patient – provider relationships at the UCI. While inadequate communication and some degree of incivility were reported, majority of patients thought the healthcare professionals were empathetic and supportive. Conclusion Health system and individual patient factors influence health-seeking for symptoms of esophageal cancer and adherence to treatment schedule for the disease. Interventions to improve access to and acceptability of esophageal cancer services, as well as increase public awareness of esophageal cancer risk factors and symptoms could lead to earlier diagnosis and potentially better survival from the disease in Uganda.

Flume experimental evaluation of the effect of rill flow path tortuosity on rill roughness based on the Manning–Strickler equation

CATENA ◽  
2014 ◽  
Vol 118 ◽  
pp. 226-233 ◽  
Author(s):  
Stefan Martin Strohmeier ◽  
Sayjro Kossi Nouwakpo ◽  
Chi-Hua Huang ◽  
Andreas Klik
Keyword(s):  
Experimental Evaluation ◽  
Flow Path ◽  
Path Tortuosity ◽  
Rill Flow
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