Behavioral diversity assisting obstacle navigation during group transportation in ant

2017 ◽  
Author(s):  
Shohei Utsunomiya ◽  
Atsuko Takamatsu
Keyword(s):  
Success Rate ◽  
Group Size ◽  
Food Item ◽  
Inconsistent Result ◽  
Behavioral Diversity ◽  
Wide Range ◽  
Pulling Forces ◽  
Transportation Behavior ◽  
Rigid Rod ◽  
Transportation Speed

AbstractCooperative transportation behavior in ants has attracted attention from a wide range of researchers, from behavioral biologists to roboticists. Ants can accomplish complex tasks as a group whereas individual ants are not intelligent (in the context of thisstudy’s tasks). In this study, group transportation and obstacle navigation in Formica japonica, an ant species exhibiting ‘uncoordinated transportation’ (primitive group transportation), are observed using two differently conditioned colonies. Analysesfocus on the effect of group size on two key quantities: transportation speed and obstacle navigation period. Additionally, this study examines how these relationships differ between colonies. The tendencies in transportation speed differ between colonies whereas the obstacle navigation period is consistently reduced irrespective of the colony. To explain this seemingly inconsistent result in transportation speed, we focus on behavioral diversity in ‘directivity’, defined as the tendency of individual ants totransport a food item toward their own preferential direction. Directivity is not always toward the nest, but rather is distributed around it. The diversity of the first colony is less than that of the second colony. Based on the above results, a mechanical model is constructed. Using the translational and rotational motion equations of a rigid rod, the model mimics a food item being pulled by single or multiple ants. The directions of pulling forces exerted by individual ants are assumed to be distributed around the direction pointing toward the nest. The simulation results suggest that, as diversity in directivity increases, so does the success rate in more complicated obstacle navigation. In contrast, depending on group size, the speed of group transportation increases in the case of lower diversity while it is almost constant in the case of higher diversity. Transportation speed and obstacle navigation success rate are in a trade-off relationship.

scholarly journals Online Food Ordering Management System

2021 ◽  
Vol 9 (VII) ◽  
pp. 2096-2107
Author(s):  
Karan Dhiman
Keyword(s):  
User Interface ◽  
Real Time ◽  
Management System ◽  
Food Item ◽  
Service Industry ◽  
Food Service ◽  
Wide Range ◽  
Ordering Systems

The main purpose of the Online Food Ordering Management System is to use it in the food-service industry. This feature helps hotels and restaurants to increase their online food ordering systems. Customers can choose from a wide range of food menu items within just a few minutes. In today’s modern food business, it's also able to deliver fast and easily to a customer’s place. The work presented as Online Food Ordering Management System simplifies the ordering process. The proposed solution presents a user interface and changes the menu to include all available options, creating customer work easier. Allows customers to order any item that they like and adjust the quantity of the food item. The order confirmation is displayed to the customer on the Homepage of the website. The order is put to the queue, updated across both the database and the admin panel, and provided in real-time. This system aids the staff with checking over orders in real-time and executing them effectively and easily with few errors. Here, the customer can also reserve a table at a restaurant of his/her choice and will get the confirmation of their reserved table on the homepage of our website.

scholarly journals Sewer and drain swabbing as a means of investigating salmonellosis

1970 ◽  
Vol 68 (4) ◽  
pp. 611-624 ◽  
Author(s):  
R. W. S. Harvey ◽  
T. H. Price
Keyword(s):  
Food Item ◽  
Infected Animal ◽  
Animal Feed ◽  
Marked Change ◽  
Human Infection ◽  
Food Handlers ◽  
Economical Method ◽  
Wide Range ◽  
Frequent Finding ◽  
Industrial Sources

SUMMARYThe use of gauze swabs in drains or sewers to clarify the path followed by a salmonella from source to human host has been reviewed in the light of experience gained in Cardiff over 15 years. This period has seen a marked change in attitudes to salmonella epidemiology in that infected food is now regarded as of greater importance than infected food handlers. In these 15 years, butchers, abattoirs and knackers' yards, markets and bakehouses have been monitored. In the bakehouse survey the existence of staff infection was demonstrated by sewage examination. Sewage investigation has also been used to show frequent entry of salmonellas into households in a residential estate. The estate was carefully chosen to exclude salmonellas from industrial sources and shops. The frequent finding of infection in this sewage implies that a commonly consumed heavily infected food item is involved. The wide range of serotypes isolated suggests an animal usually fed on infected animal feed. Poultry and pigs are put forward as animals liable to spread salmonellosis to man.It is hoped that clarification of the salmonella pathway may eventually lead to measures likely to prevent the transmission of infection to man. It is also suggested that swabs placed in abattoir drains serve as an economical method of obtaining warning of a persistent build-up of contamination. The persistence of a serotype in an abattoir is not infrequently followed by human infection.

scholarly journals Should Vascular Surgery Patients Be Screened Preoperatively for Methicillin-Resistant Staphylococcus aureus?

2009 ◽  
Vol 30 (12) ◽  
pp. 1158-1165 ◽  
Author(s):  
Bruce Y. Lee ◽  
Becky Y. Tsui ◽  
Rachel R. Bailey ◽  
Kenneth J. Smith ◽  
Robert R. Muder ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Vascular Surgery ◽  
Success Rate ◽  
Economic Value ◽  
Cost Effective ◽  
Third Party ◽  
Computer Simulation Model ◽  
Success Rates ◽  
Methicillin Resistant ◽  
Wide Range

Background.Methicillin-resistant Staphylococcus aureus (MRSA) can cause severe infection in patients who are undergoing vascular surgical operations. Testing all vascular surgery patients preoperatively for MRSA and attempting to decolonize those who have positive results may be a strategy to prevent MRSA infection. The economic value of such a strategy has not yet been determined.Methods.We developed a decision-analytic computer simulation model to determine the economic value of using such a strategy before all vascular surgical procedures from the societal and third-party payer perspectives at different MRSA prevalence and decolonization success rates.Results.The model showed preoperative MRSA testing to be cost-effective (incremental cost-effectiveness ratio, <$50,000 per quality-adjusted life year) when the MRSA prevalence is ≥0.01 and the decolonization success rate is ≥0.25. In fact, this strategy was dominant (ie, less costly and more effective) at the following thresholds: MRSA prevalence ≥0.01 and decolonization success rate ≥0.5, and MRSA prevalence ≥0.025 and decolonization success rate ≥0.25.Conclusion.Testing and decolonizing patients for MRSA before vascular surgery may be a cost-effective strategy over a wide range of MRSA prevalence and decolonization success rates.

A Numerical Method for Coupling Nano-Scale Molecular Binding With Mesoscale Cellular Deformation

2009 ◽  
Author(s):  
Vijay K. Gupta ◽  
Charles D. Eggleton
Keyword(s):  
Cell Adhesion ◽  
Hydrodynamic Forces ◽  
Scale Model ◽  
Immersed Boundary ◽  
Molecular Binding ◽  
Nano Scale ◽  
Threshold Phenomenon ◽  
Model Combining ◽  
Wide Range ◽  
Pulling Forces

Cell adhesion plays a pivotal role in diverse biological processes, including inflammation and thrombosis. Changes in cell adhesion can be the defining event in a wide range of diseases, including cancer, osteoporosis, atherosclerosis, and arthritis. Cells are exposed constantly to hemodynamic/hydrodynamic forces and the balance between the dispersive hydrodynamic forces and the adhesive forces generated by the interactions of membrane-bound receptors and their ligands determines cell adhesion. The ultimate objective of our work is to develop software that can simulate the adhesion of cells colliding under hydrodynamic forces that can be used to investigate the complex interplay among the physical mechanisms and scales involved in the adhesion process. Here, we review the development of a multi-scale model combining Monte-Carlo models of molecular binding with the Immersed Boundary Method for cellular-hydrodynamic interactions. This model predicted for the first time that the rolling of more compliant cells is relatively smoother and slower compared to cells with stiffer membranes, due to increased cell-substrate contact area. At the molecular level, we show that the average number of bonds per cell as well as per single microvillus decreases with increasing membrane stiffness. The numerical model was modified to compare the effects of different kinetic models of molecular binding on cell rolling. Simulations predict that the catch-slip bond behavior and to a lesser extent bulk cell deformation are responsible for the shear threshold phenomenon. In bulk flow, shear rate has been shown to critically affect the kinetics and receptor specificity of cell-cell interactions. We are currently simulating the adhesion of two PMN cells in quiescent conditions and the exposing the cells to external pulling forces and shear flow in order to investigate the behavior of the nano-scale molecular bonds to forces applied at the cellular scale.

Impact of instructional decisions on the effectiveness of cooperative learning in chemistry through meta-analysis

2017 ◽  
Vol 18 (1) ◽  
pp. 271-278 ◽  
Author(s):  
Andrew Apugliese ◽  
Scott E. Lewis
Keyword(s):  
Cooperative Learning ◽  
Group Size ◽  
Meta Analysis ◽  
Educational Reforms ◽  
Instructional Decisions ◽  
Wide Range ◽  
Pedagogical Interventions ◽  
Class Period ◽  
The Impact ◽  
Maximum Group

Meta-analysis can provide a robust description of the impact of educational reforms and also offer an opportunity to explore the conditions where such reforms are more or less effective. This article describes a meta-analysis on the impact of cooperative learning on students’ chemistry understanding. Modifiers in the meta-analysis are purposefully chosen to model instructors’ decisions in implementing cooperative learning. Modifiers investigated include: using cooperative learning periodically or in every class period; setting a maximum group size at four or smallerversusfive or larger; using closed-ended or open-ended assessments; and assessing a single topic or assessing the cumulative topics in the course. The results showed cooperative learning's effectiveness is robust across a wide range of instructional decisions except no evidence of effectiveness was found with cumulative assessments. The overall results from the meta-analysis provide a benchmark for evaluating future efforts to evaluate pedagogical interventions in chemistry.

Synthesis, Characterization, and Dynamics of a Rod/Sphere Organoceramic Composite Liquid

1992 ◽  
Vol 274 ◽  
Author(s):  
Mark A. Tracy ◽  
R. Pecora
Keyword(s):  
Experimental Studies ◽  
Liquid System ◽  
Organic Coating ◽  
Molecular Weights ◽  
Naturally Occurring ◽  
Wide Range ◽  
Molecular Composites ◽  
Ceramic Precursors ◽  
Rigid Rod ◽  
System 1

ABSTRACTComposite liquids – liquids composed of polymers, particles, and small molecule solvents – constitute an important class of synthetic and naturally occurring materials. Examples include molecular composites, ceramic precursors, lubricants, adhesives, and the cytoplasm in biological cells. Due to the complexity of these liquids, experimental studies of precisely defined systems are essential in developing an understanding of the interactions between all components in the liquid. Unfortunately, such fundamental studies have been relatively rare due to both the difficulty of synthesizing precisely defined composite liquids and the lack of adequate experimental methods to monitor the motions of the various constituents.We have recently reported the synthesis, characterization and some studies of the dynamics of a rod/sphere composite liquid system [1]. In our case the “polymer” constituent is a rigid rod polymer, poly(γ-benzyl-α,L-glutamate) (PBLG). Rigid rod polymers are frequently used in composite liquids as viscosity enhancers. PBLG is commercially available in a wide range of molecular weights and its static and dynamic behavior in dilute and nondilute solutions has been studied. It, in addition, forms mesophases in the concentrated regime. The ceramic “particles” in our composite liquid are coated silica spheres. These spheres are synthesized by the method of Stober et. al. [2] and coated with an organic coating (3-(trimethoxysilyl)propyl methacrylate (TPM)) following a procedure based on that of Philipse et. al. [3] to render them dispersible in organic solvents. The spheres with sizes in the range from 10 nm up to almost 1μm can be synthesized with a relatively narrow size distribution. The solvent in our studies is dimethylformamide (DMF). Both polymer and particle are dispersible as singlets (nonaggregating) in these solvents and the PBLG retains its rigid (or nearly rigid) rod conformation. The diffusion of both the polymer and the sphere in the composite liquid is measured by dynamic light scattering (DLS) [4]. In this paper, we focus on the spheres and examine the effects of rod concentration and rod length on the diffusion of different size spheres. This study suggests that the solution microstructure has an important influence on sphere diffusion.

scholarly journals Article Review on Vectran-Super Fiber from Thermotropic Crystals of Rigid-Rod Polymer

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Derseh Yilie limeneh ◽  
Kelem Tiessasie Yilma
Keyword(s):  
Tensile Strength ◽  
Liquid Crystal ◽  
Melt Spinning ◽  
High Strength ◽  
Extrusion Process ◽  
Liquid Crystal Polymer ◽  
Fiber Axis ◽  
Crystal Polymer ◽  
Wide Range ◽  
Rigid Rod

According to the economic and environmental perspective, multifilament Vectran, yarn spun from liquid crystal polymer, is important because of its quite simple processing during spinning in a wide range of injection moulding, extrusion moulding, and melt spinning. Vectran fiber is an aromatic polyester spun from a liquid crystal polymer in a melt extrusion process. This process orients the molecules along the fiber axis, resulting in a high tenacity fiber, and Vectran melts at 330°C. Heat treatment can improve and vary the tensile strength of Vectran fiber. On average, tensile strength for Vectran is 26 grams/denier (grouped as a high tenacity grade) and the strength of the fiber is maintained after several flexing and bending actions. Abrasion resistance of Vectran is even higher than a similarly sized aramid yarn. In addition, the original dimensions are maintained under variance of temperature with negligible creep and shrinkage. Vectran fiber, characterized by its golden color, high strength and modulus, thermal stability at high temperatures, low creep, and good chemical stability, can be used in many various industries starting from ropes and cables to profound sea survey and military products.

scholarly journals Fluctuating survival selection explains variation in avian group size

2016 ◽  
Vol 113 (18) ◽  
pp. 5113-5118 ◽  
Author(s):  
Charles R. Brown ◽  
Mary Bomberger Brown ◽  
Erin A. Roche ◽  
Valerie A. O’Brien ◽  
Catherine E. Page
Keyword(s):  
Group Size ◽  
Colony Size ◽  
Information Transfer ◽  
Size Variation ◽  
Directional Selection ◽  
Net Benefit ◽  
First Case ◽  
Survival Selection ◽  
Wide Range ◽  
Directional Change

Most animal groups vary extensively in size. Because individuals in certain sizes of groups often have higher apparent fitness than those in other groups, why wide group size variation persists in most populations remains unexplained. We used a 30-y mark–recapture study of colonially breeding cliff swallows (Petrochelidon pyrrhonota) to show that the survival advantages of different colony sizes fluctuated among years. Colony size was under both stabilizing and directional selection in different years, and reversals in the sign of directional selection regularly occurred. Directional selection was predicted in part by drought conditions: birds in larger colonies tended to be favored in cooler and wetter years, and birds in smaller colonies in hotter and drier years. Oscillating selection on colony size likely reflected annual differences in food availability and the consequent importance of information transfer, and/or the level of ectoparasitism, with the net benefit of sociality varying under these different conditions. Averaged across years, there was no net directional change in selection on colony size. The wide range in cliff swallow group size is probably maintained by fluctuating survival selection and represents the first case, to our knowledge, in which fitness advantages of different group sizes regularly oscillate over time in a natural vertebrate population.

European Experience with a System for Bifurcated Stent-Graft Insertion

1997 ◽  
Vol 4 (1) ◽  
pp. 13-22 ◽  
Author(s):  
Timothy A.M. Chuter ◽  
George Wendt ◽  
Brian R. Hopkinson ◽  
R. Alan P. Scott ◽  
Bo Risberg ◽  
...  
Keyword(s):  
Success Rate ◽  
Stent Migration ◽  
Graft Thrombosis ◽  
European Experience ◽  
Wide Range ◽  
The Difference ◽  
Procedural Success ◽  
Current Selection

Purpose: To test an endovascular aneurysm exclusion system in the presence of a wide range of challenging anatomic features. Methods: Bifurcated endovascular stent-grafts were inserted in 52 patients and followed with serial computed tomography for up to 3 years. The device underwent several modifications during this time, the most significant of which represent the difference between the homemade (n = 42) and industry-made (n = 10) versions. Results: The initial procedural success rate was 92% in the homemade group and 100% in the industry-made group. In the 3 years of follow-up, the long-term success rate was 64% in the homemade group and 90% in the industry-made group. The primary reasons for failure in the homemade group were graft thrombosis due to kinking early in the series and proximal stent migration later in our experience. All cases of migration occurred when the neck was < 15 mm in length, the neck was lined with thrombus, or the stent was implanted > 15 mm from the renal arteries. Kinking was subsequently overcome by implanting Wallstents throughout the graft limbs. The sole failure in the industry-made group was a case in which collateral perfusion reached the aneurysm through patent lumbar arteries. Conclusions: The fruits of this experience are a better technique, a better device, and, most importantly, a better understanding of the system's limits, as reflected in the current selection criteria.

scholarly journals Endoscopic endonasal cerebrospinal fluid rhinorrhea repair: a cohort study in Iraq

2021 ◽  
Vol 37 (1) ◽  
Author(s):  
Ammar Abdulkadhim Hasan ◽  
Saad Farhan Al-Saedi ◽  
Mukhallad Mahdi Saleh ◽  
Hani Musa Al-Akbi
Keyword(s):  
Cerebrospinal Fluid ◽  
Success Rate ◽  
Fascia Lata ◽  
Csf Leak ◽  
Surgical Approaches ◽  
Tensor Fascia Lata ◽  
Endoscopic Endonasal ◽  
Csf Rhinorrhea ◽  
Cerebrospinal Fluid Rhinorrhea ◽  
Wide Range

Abstract Background Cerebrospinal fluid (CSF) rhinorrhea is a condition where the protective fluid that surrounds the brain finds its way into the nose and sinuses, often appearing as a very watery runny nose. The main surgical approaches for the surgical repair of CSF leaks are intracranial and extracranial. Over the last decade, endoscopic surgery has established itself as the most widely used technique for the repair of CSF fistula. The current study aimed to describe the use of nasal endoscopic technique in the management of cerebrospinal fluid rhinorrhea repair. Results Results of our study showed that in addition to CSF leak, 40% of the patients had headache and 17.5% had repeated meningitis. Half of the etiologies for the CSF leak were spontaneous, 35% were congenital, and 15% were traumatic. The more frequent site of leak was left cribriform plate (37.5%). In the majority of patients, 37/40 (92.5%), the type of graft was tensor fascia lata and fat, while in the remaining 3 patients, type of graft was tensor fascia lata and bone, bone and fat, and tensor fascia lata. The repair succeeded in 35 patients giving a success rate of 87.5%. Conclusion It can be concluded that wide range of age groups from 2–62 years presented as CSF rhinorrhea with female predominance, and there was high success rate of endoscopic CSF rhinorrhea repair with low morbidity.

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