Inbreeding depression and the cost of inbreeding on seed germination

2015 ◽  
Vol 25 (4) ◽  
pp. 355-385 ◽  
Author(s):  
Jerry M. Baskin ◽  
Carol C. Baskin
Keyword(s):  
Seed Germination ◽  
Case Studies ◽  
Inbreeding Depression ◽  
Life History Traits ◽  
Seed Mass ◽  
Natural World ◽  
Dormancy Breaking ◽  
The Cost ◽  
The Relationship ◽  
Better Than

AbstractWe review the literature on effects of inbreeding depression (ID) on seed germination for 743 case studies of 233 species in 64 families. For 216 case studies, we also review the relationship between mass and germination in inbred vs. outbred seeds. Inbred seeds germinated equally well as outbred seeds in 51.1% of 743 case studies, but better than outbred seeds in only 8.1%. In c. 50.5% of 216 cases, mass of inbred seeds was equal to (38.0%) or larger than (12.5%) that of outbred seeds. The magnitude of ID spans most of the − 1 to +1 range for relative performance for germination of inbred vs. outbred seeds; in contrast to what might be expected, seed germinability often is not negatively correlated with the coefficient of inbreeding (F) or positively corrected with population genetic diversity; neither heterosis nor outbreeding depression for germination is common in crosses between populations; and ID in most endemics is low and does not differ from that of widespread congeners. Our results on the effects of ID on seed mass and germination do not agree with the limited number of comparisons Darwin (1876) made on the effects of selfing vs. outcrossing on these two life-history traits. Recommendations are made on how to improve dormancy breaking and germination procedures in order to make the results of studies on ID more relevant to the natural world.

14. Theory and Practice of Continental Warfare

2015 ◽  
Author(s):  
Stephen Biddle
Keyword(s):  
Technological Change ◽  
Case Studies ◽  
Gulf War ◽  
Theory And Practice ◽  
Actual Experience ◽  
European Theatre ◽  
The Cost ◽  
The Relationship ◽  
Second World ◽  
Tight Integration

This chapter examines the theory and practice of continental warfare, with particular emphasis on the relationship between ideas on conventional land warfare and actual experience since 1900. It considers technological change, including mechanization, as the central challenge facing modern theorists as well as tactical and doctrinal responses that emerged very quickly in reaction to modern weapons' radical lethality. These responses emphasized cover, concealment, tight integration of suppressive fire and movement, depth, and reliance on withheld reserves at the cost of lighter forward deployments. These concepts subsequently formed the foundation for most modern systems of tactics and doctrine. The chapter explores the relationship between theory and practice in continental warfare by focusing on four case studies: the European theatre in the First and Second World Wars, the Arab–Israeli War of 1973, and the Gulf War of 1991.

scholarly journals Evolution of Clustering Quantified by a Stochastic Method—Case Studies on Natural and Human Social Structures

2020 ◽  
Vol 12 (19) ◽  
pp. 7972
Author(s):  
G.-Fivos Sargentis ◽  
Theano Iliopoulou ◽  
Stavroula Sigourou ◽  
Panayiotis Dimitriadis ◽  
Demetris Koutsoyiannis
Keyword(s):  
Case Studies ◽  
Large Scale ◽  
Spatial Information ◽  
Physical World ◽  
Natural World ◽  
Social Structures ◽  
Societal Challenges ◽  
The Cost ◽  
Organizational Needs ◽  
The Universe

Clustering structures appearing from small to large scales are ubiquitous in the physical world. Interestingly, clustering structures are omnipresent in human history too, ranging from the mere organization of life in societies (e.g., urbanization) to the development of large-scale infrastructure and policies for meeting organizational needs. Indeed, in its struggle for survival and progress, mankind has perpetually sought the benefits of unions. At the same time, it is acknowledged that as the scale of the projects grows, the cost of the delivered products is reduced while their quantities are maximized. Thus, large-scale infrastructures and policies are considered advantageous and are constantly being pursued at even great scales. This work develops a general method to quantify the temporal evolution of clustering, using a stochastic computational tool called 2D-C, which is applicable for the study of both natural and human social spatial structures. As case studies, the evolution of the structure of the universe, of ecosystems and of human clustering structures such as urbanization, are investigated using novel sources of spatial information. Results suggest the clear existence both of periods of clustering and declustering in the natural world and in the human social structures; yet clustering is the general trend. In view of the ongoing COVID-19 pandemic, societal challenges arising from large-scale clustering structures are discussed.

Cost Effectiveness of Operator Features in Equipment Design

1981 ◽  
Vol 25 (1) ◽  
pp. 385-389
Author(s):  
Jeremy C. Williams
Keyword(s):  
Human Factors ◽  
Synthetic Data ◽  
Considerable Effect ◽  
Negotiation Process ◽  
Additional Tool ◽  
Calls For Service ◽  
Job Aids ◽  
The Cost ◽  
The Relationship ◽  
Better Than

In design negotiation, the attribution of credible values to the incorporation or deletion of operator features allows engineers the freedom to judge the overall effect of human factors recommendations in relation to the achievement of a design specification. Likewise in the development phase, product planners frequently need more precise statements about productivity, training needs and general operational performance than, “it will be greater/less, worse/better than…”. The method described utilises measured and synthetic data, learning theory and Markov processes to calculate the likelihood of operator task failure. These failure rates are then treated via filter factors derived from the application of a variation of Delphi Technique to give a global statement of the likelihood of operator failure resulting in unscheduled calls for service. Using the relationship between the cost of service calls and the overall life cost of developing, manufacturing, marketing and supporting a leased product, it is then possible to place credible values on the design features in question. Thus during the design process it becomes feasible to calculate the likely effects of human factors recommendations and modifications in relation to manufacturing costs, and thereby facilitate rational assessment of their implementation on a sound economic basis. This technique has been used to considerable effect, and represents a useful additional tool for the human factors practitioner in the design negotiation process. Further developments and refinements are planned, and it is anticipated that a similar technique will shortly be available to enable assessment of the effectiveness of product training programs and job aids.

scholarly journals Studying Learner Behavior in Online Courses With Free-Certificate Coupons: Results From Two Case Studies

2020 ◽  
Vol 21 (1) ◽  
pp. 1-22 ◽  
Author(s):  
Joshua Littenberg-Tobias ◽  
José A. Ruipérez-Valiente ◽  
Justin Reich
Keyword(s):  
Case Studies ◽  
Online Courses ◽  
Massive Open Online Courses ◽  
Completion Rates ◽  
Learning Behavior ◽  
Massive Open Online ◽  
The Cost ◽  
The Relationship ◽  
Influence Behavior

The relationship between pricing and learning behavior is an important topic in research on massive open online courses (MOOCs). We report on two case studies where cohorts of learners were offered coupons for free certificates to explore how price reductions might influence behavior in MOOC-based online learning settings. In Case Study 1, we compare participation and certification rates between courses with and without free-certificate coupons. In the courses with a free-certificate track, participants signed up for the verified-certificate track at higher rates, and completion rates among verified students were higher than in the paid-certificate track courses. In Case Study 2, we compare learner behavior within the same courses by whether they received access to a free-certificate track. Access to free certificates was associated with lower certification rates, but overall, certification rates remained high, particularly among those who viewed the courses. These findings suggest that some incentives, other than simply the cost of paying for a verified-certificate track, may motivate learners to complete MOOCs.

A Māori Girl Watches, Listens, and Learns – Coming of Age from an Indigenous Viewpoint: Mauri (Merata Mita, 1988)

2018 ◽  
Author(s):  
Alistair Fox
Keyword(s):  
Indigenous People ◽  
Coming Of Age ◽  
Natural World ◽  
Feature Film ◽  
Indigenous Woman ◽  
Spiritual Dimension ◽  
The World ◽  
Life Force ◽  
Relationship Of ◽  
The Relationship

This chapter examines Merata Mita’s Mauri, the first fiction feature film in the world to be solely written and directed by an indigenous woman, as an example of “Fourth Cinema” – that is, a form of filmmaking that aims to create, produce, and transmit the stories of indigenous people, and in their own image – showing how Mita presents the coming-of-age story of a Māori girl who grows into an understanding of the spiritual dimension of the relationship of her people to the natural world, and to the ancestors who have preceded them. The discussion demonstrates how the film adopts storytelling procedures that reflect a distinctively Māori view of time and are designed to signify the presence of the mauri (or life force) in the Māori world.

Flesh Searches in China

Asian Survey ◽  
2016 ◽  
Vol 56 (2) ◽  
pp. 325-347 ◽  
Author(s):  
Patrick Gorman
Keyword(s):  
Case Studies ◽  
Communist Party ◽  
Chinese Communist Party ◽  
Social Space ◽  
Contemporary China ◽  
Chinese State ◽  
The Chinese Communist Party ◽  
The Relationship

This article explores the relationship between netizens and the Chinese Communist Party by investigating examples of “flesh searches” targeting corrupt officials. Case studies link the initiative of netizens and the reaction of the Chinese state to the pattern of management of social space in contemporary China.

The Awareness Level of the Safety and Health of the Operational Level

2017 ◽  
Vol 3 (1) ◽  
pp. 42
Author(s):  
Roshanira Che Mohd Noor ◽  
Nur Atiqah Rochin Demong
Keyword(s):  
Health And Safety ◽  
Health Conditions ◽  
Effective Strategies ◽  
Operational Level ◽  
Safety And Health ◽  
Health Factors ◽  
The Cost ◽  
The Relationship ◽  
Awareness Level

Providing a safe and healthy workplace is one of the most effective strategies in for holding down the cost of doing construction business. It was a part of the overall management system to facilitate themanagement of the occupational health and safety risk that are associated with the business of the organization. Factors affected the awareness level inclusive of safety and health conditions, dangerous working area, long wait care and services and lack of emergency communication werethe contributed factors to the awareness level for the operational level. Total of 122 incidents happened at Telekom Malaysia Berhad as compared to year 2015 only 86 cases. Thus, the main objective of this study was to determine the relationship between safety and health factors and the awareness level among operational workers.The determination of this research was to increase the awareness level among the operational level workerswho committing to safety and health environment.

Dormancy-breaking Studies on Echinacea angustifolia

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 456f-457 ◽  
Author(s):  
Ali O. Sari ◽  
Mario R. Morales ◽  
James E. Simon
Keyword(s):  
Native Americans ◽  
Seed Germination ◽  
Tap Water ◽  
The United States ◽  
Market Demand ◽  
Dormancy Breaking ◽  
Echinacea Angustifolia ◽  
Native Populations ◽  
Percent Germination ◽  
Dry Heating

Echinacea is a medicinal plant native to North America. It was used extensively by native Americans in the treatment of their ailments. It is presently one of the most popular medicinal plants in the United States. Its popularity has created a large market demand for the roots and foliage of the plant. The gathering of echinacea from the wild is leading to the reduction of native populations and the destruction of its genetic diversity. Cultivation of medicinal echinaceas is hindered by a low seed germination. Dormancy breaking studies were done on freshly harvested seeds of Echinacea angustifolia. Seed lots were placed under light at a constant temperature of 25 °C and at alternate temperatures of 25/15 °C for 14/10 h, respectively. Germination was more rapid and uniform and percent germination higher at 25 °C than at 25/15 °C. Seed tap-water soaking, dry heating, and sharp heating alteration did not increase germination. The application of 1.0 mM ethephon (2-chloroethylphosphoric acid) increased seed germination to 94% at 25 °C and 86% at 25/15 °C. Untreated seeds gave 65% germination at 25 °C and 11% at 25/15 °C. The application of 2500 mg·L–1 and 3500 mg·L–1 of GA to dry seeds and 2500 mg·L–1 to seeds that have been soaked under tap water and then dried increased germination to 82%, 83%, and 83% at 25 °C and 64%, 78%, and 64% at 25/15 °C, respectively.

Pound Wise and Penny Foolish? Weight Loss and The Dynamics of Health Care Spending

2011 ◽  
Vol 14 (2) ◽  
Author(s):  
Thomas G Koch
Keyword(s):  
Weight Loss ◽  
Cost Savings ◽  
Cost Effective ◽  
Economic Consequences ◽  
Health Care Spending ◽  
Order Of Magnitude ◽  
Dynamic Measures ◽  
The Cost ◽  
The Impact ◽  
The Relationship

Current estimates of obesity costs ignore the impact of future weight loss and gain, and may either over or underestimate economic consequences of weight loss. In light of this, I construct static and dynamic measures of medical costs associated with body mass index (BMI), to be balanced against the cost of one-time interventions. This study finds that ignoring the implications of weight loss and gain over time overstates the medical-cost savings of such interventions by an order of magnitude. When the relationship between spending and age is allowed to vary, weight-loss attempts appear to be cost-effective starting and ending with middle age. Some interventions recently proven to decrease weight may also be cost-effective.

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