2,140 research outputs found
Dictators, Repression and the Median Citizen: An āEliminations Modelā of Stalinās Terror (Data from the NKVD Archives)
This paper sheds light on dictatorial behavior as exemplified by the mass terror campaigns of Stalin. Dictatorships ā unlike democracies where politicians choose platforms in view of voter preferences ā may attempt to trim their constituency and thus ensure regime survival via the large scale elimination of citizens. We formalize this idea in a simple model and use it to examine Stalinās three large scale terror campaigns with data from the NKVD state archives that are accessible after more than 60 years of secrecy. Our model traces the stylized facts of Stalinās terror and identifies parameters such as the ability to correctly identify regime enemies, the actual or perceived number of enemies in the population, and how secure the dictators power base is, as crucial for the patterns and scale of repression.Dictatorial systems, Stalinism, Soviet State and Party archives, NKVD, OPGU,Repression
Particle filter-based parameter estimation in a model of the human circadian rhythm
Recent insights into the effects of light on human health call for a more human-centric approach in automatic lighting control systems. We contribute to the provisioning of lighting settings tailored to the needs of individuals by addressing the challenge of predicting the response of an individualās circadian rhythm to light exposure. Existing models of the human circadian rhythm are not tailored to individual physiological characteristics such as intrinsic circadian period, light sensitivity and age. We propose to improve model accuracy by using Bayesian statistical inference to estimate the values of model parameters that reflect these physiological characteristics. We illustrate our generic method by applying to a combination of two popular models of the circadian rhythm. By processing individual light exposure- and actigraphy data recoded during a field trial with 20 human subjects with a Particle Filter, we estimate each subjectās intrinsic circadian period. When correlating these to the subjectsā Munich Chronotype Questionnaire Midsleep on Free Days time, a significant relationship was found: r > 0.6 and p < 0.01. This shows the proposed method has good potential for improving model accuracy
Plant breeding and the nutritive value of crop residues. Proceedings of a workshop
Presents papers dealing with the use of crop residues as livestock feed in smallholder crop/livestock farming systems, and the role of plant breeding in maintaining or improving their nutritive value. Discusses factors limiting the nutritive value of crop residues, and the effect of genotype and environment on the nutritive value of crop residues. Outlines perspectives and implications for crop improvement programmes. Includes recommendations
Examining The Role of Information Technology in Cultivating Firmsā Dynamic Marketing Capabilities
Dynamic capabilities enable firms to reconfigure limited resources or relative strengths to respond to rapid changes in market conditions. This study considers the central role of IT in creating and enhancing dynamic capabilities by analyzing the essential determinants of dynamic marketing capabilities and proposing a model that includes market orientation, IT infrastructure capabilities, and use of IT to support CRM. Tests using a large-scale survey support the model and most of its hypotheses. The results reveal significant effects of a firmās market orientation and use of IT to support CRM and the functionality of IT infrastructure capabilities on dynamic marketing capabilities
Maasai herding: An analysis of the livestock production system of Maasai pastoralists in eastern Kajiado District, Kenya
The first chapter gives a brief description of a pastoral production system, as envisaged by the study team and outlines the multi-disciplinary approach of the study, its sampling design and the data collected. Chapters 2 & 3 describe Kenya's biophysical and socio-economic environments, within which the Maasai livestock production system operates. The biophysical environment of the study site is described in detail in Chapter 4. Chapter 5 describes the social organization of the Maasai and how it affects their use of livestock and grazing resources. The division and specialisation of labour by age and sex classes are described in chapter 6. The short term productivity of Maasai cattle, sheep and goats is analysed in Chapter 7. Chapter 8 analyses how the Maasai used their livestock and how this determined the mix of species, sex and age of the livestock they kept. It also analyses the pattern of food and non-food consumption and the resulting patterns of cash income and expenditure. Chapter 9 presents an economic analysis of the short-term livestock production of the Maasai. First the short-term costs and returns of Maasai livestock production are analysed as observed during the study period. Subsequently the operation of the regional livestock market and its links with the pastoral hinterland and the final livestock markets are described and the efficiency analysed. Finally the historical terms of trade of the pastoral Maasai and how they have affected their welfare is discussed
Prosthetic knee stability during the push-off phase of walking - experimental findings
Most of the energy needed for ambulation is generated during the double support phase of walking. Knee flexion during push-off is crucial to maintain the walking velocity. Since users of an above-knee prosthesis have to stabilize the knee with the hip muscles, and regular knee mechanisms are not stable during flexion, this may cost a large effort. This paper deals with experimental findings of walking with different types of knees. The results indicate that for walking with a more stable knee, the symmetry increases and the net hip moments of force, required to stabilize the knee, reduce. The mechanical work however, performed at the hip joint at the prosthetic side, remains about equa
AgricultureāNutrition Situation in the Pacific Island States
In 2016, CTA embarked on a joint project with the International Fund for Agricultural Development (IFAD) entitled āLeveraging the Development of Local Food Crops and Fisheries Value Chains for Improved Nutrition and Sustainable Food Systems in the Pacific Islands (with a focus on Fiji, Kiribati, the Marshall Islands, Samoa, Solomon Islands, Tonga, and Vanuatu)ā. This four-year project aimed at strengthening the capacity of the Pacific island governments, farmer and private-sector organisations and subregional institutions to develop innovative strategies and programmes that can increase poor rural peopleās access to nutritious and healthy food and to mobilise the funds needed to deliver these.
Through the project and previous work, a series of rapid country scans were commissioned to collect detailed information on the agriculture, food and nutrition situation in the seven Pacific island nations to determine the entry points that provide the greatest opportunity for strengthening the agricultureānutritionāincome nexus. This document synthesises the key findings from across the countries, draws out lessons for policy and identifies opportunities for future investments to address the key food and nutrition security issues that the islands face
Device equivalence in integrated optics
The concept of device equivalence is introduced. In equivalent devices, the light propagation can be described by identically evolving modal expansions, resulting in identical power transfer ratios. By first applying this concept to a z-invariant structure with a low refractive-index contrast it is shown how a normalized coordinate space can be defined in which equivalent structures have exactly the same geometry. Subsequently it is shown how this normalized coordinate space can be defined for z-variant integrated optical devices, again provided that the lateral refractive-index contrast is small. This normalization makes it possible to perform numerical device simulations in normalized coordinate space, the results being applicable to a large set of equivalent devices. Furthermore, starting from a known design, it simplifies redesigning that device for use at another wavelength or using other materials significantly, the resulting device being equivalent to the original on
A Web-Based Recommendation System for Mobile Phone Selection
Mobile phones have become indispensable in our everyday life. The fierce market competition characterized by rapid expansion of advanced functionality and feature is making consumersā mobile phone selections increasingly complex and challenging. In this study, we use Analytic Hierarchy Process (AHP), a multiple criteria decision method, to build a recommendation system for mobile phones selection. AHP provides a structural and easily comprehensible model for making product choices. We empirically evaluate our recommendation system by conducting a controlled experiment that involved 244 mobile phone users. Our analysis results indicate that the use of the proposed system results in higher satisfaction than that associated with the rank-based and equal-weight based benchmark systems
A xylenol orange-based screening assay for the substrate specificity of flavin-dependent para-phenol oxidases
Vanillyl alcohol oxidase (VAO) and eugenol oxidase (EUGO) are flavin-dependent enzymes that catalyse the oxidation of para-substituted phenols. This makes them potentially interesting biocatalysts for the conversion of lignin-derived aromatic monomers to value-added compounds. To facilitate their biocatalytic exploitation, it is important to develop methods by which variants of the enzymes can be rapidly screened for increased activity towards substrates of interest. Here, we present the development of a screening assay for the substrate specificity of para-phenol oxidases based on the detection of hydrogen peroxide using the ferric-xylenol orange complex method. The assay was used to screen the activity of VAO and EUGO towards a set of twenty-four potential substrates. This led to the identification of 4-cyclopentylphenol as a new substrate of VAO and EUGO and 4-cyclohexylphenol as a new substrate of VAO. Screening of a small library of VAO and EUGO active-site variants for alterations in their substrate specificity led to the identification of a VAO variant (T457Q) with increased activity towards vanillyl alcohol (4-hydroxy-3-methoxybenzyl alcohol) and a EUGO variant (V436I) with increased activity towards chavicol (4-allylphenol) and 4-cyclopentylphenol. This assay provides a quick and efficient method to screen the substrate specificity of para-phenol oxidases, facilitating the enzyme engineering of known para-phenol oxidases and the evaluation of the substrate specificity of novel para-phenol oxidases
- ā¦