Diseño e implementación de un módulo de crecimiento bacteriano dependiente de nutrientes en el simulador GRO

Hace no más de una década que empezó a escucharse el término biología sintética. Este área de estudio emergente consiste en la ingeniería y programación de sistemas biológicos, tratando la biología como una tecnología programable a la que aplican los principios y metodologías de la ingeniería, con el fin de crear nuevas funcionalidades genéticas desde cero, procurando asÍ algún beneficio como por ejemplo, programar células bacterianas para producir biocombustibles. Sin embargo, para la creación de dichas funcionalidades es necesario conocer bien al organismo sobre el que se van a implantar. Por este motivo, los biólogos sintéticos emplean bacterias en sus estudios, ya que es la forma de vida más simple, está presente en prácticamente todos los nichos ecológicos, desempeña algunas de las funcionalidades vitales para los humanos y lo mas importante, se conoce prácticamente todo su material genético. Los experimentos son costosos en tiempo y dinero, siendo necesaria la ayuda de herramientas que faciliten esta labor, los simuladores. En PLASWIRES, proyecto europeo de biología sintética en el que se engloba este este trabajo, el simulador empleado es GRO. Sin embargo, en GRO el crecimiento de las bacterias ocurre de forma exponencial y sin restricciones, generando comportamientos poco realistas. Por ello, se ha considerado relevante en biología sintética, y en el simulador GRO en particular, disponer de un modelo de crecimiento bacteriano dependiente de los nutrientes. El desarrollo de este trabajo se centra en la implementación de un módulo de consumo de nutrientes en colonias de bacterias simuladas con GRO, introduciendo así la limitación de nutrientes y evitanto que las bacterias crezcan exponencialmente. Se han introducido nutrientes en el medio y la capacidad de consumirlos, con el objetivo de obtener un crecimiento ajustado al que ocurre en la naturaleza. Además, se ha desarrollado en GRO una nueva función de adquisición de volumen, que condiciona el volumen adquirido por cada bacteria en función de los nutrientes. La implentación de las dos aportaciones presentadas ha supuesto la adición de funcionalidad extra a GRO, convirtiéndolo en el único simulador de bacterias que tiene en cuenta el crecimiento bacteriano dependiente de nutrientes.---ABSTRACT---It has been in this last decade that the synthetic biology term began to be heard. This emergent area of study consists in the engineering and programming of biological systems, dealing with biology as a programable technology in which the engineering principles and methodologies are applied in order to create novel genetic functinalities from scratch, obtaining some advatages such as programmed bacteria in order to produce biofuels. However, to create this functionalities, it is necessary to know well the organisms in which they are going to be implemented. For this reason, synthetic biology researchers use bacteria, because it is the simplest life form, it can be found in almost all the ecological niche, it does some vital function to humans and, most important, almost all of its genetic information is known. Experiments are expensive in time and money, making it necessary to use tools to ease this task: the simulators. In PLASWIRES, the european synthetic biology project in which this work is included, the simulator used is GRO. However, the bacterial growth in GRO is exponential and it does not have restrictions, generating unrealistic behaviours. Therefore, it has been considered relevant in synthetic biology, and in a particular way in GRO, to provide a bacterial growth model dependent on nutrient. This work focuses on the implementation of a nutrient consumption module in bacteria colonies simulated with GRO, introducing a nuntrient limitation and avoiding the bacteria exponential growth. The module introduces nutrients and the capacity for bacteria to consume them, aiming to obtain realistic growth simulations that fit the observations made in nature. Moreover, an adquisition volumen function has been developed in GRO, determining the volumen depending on nutrients. This two contributions make GRO the only bacteria simulator that computes growth depending on nutrients

An evolutionary approach to the delineation of functional areas based on travel-to-work flows

This paper presents a new approach to the delineation of local labor markets based on evolutionary computation. The aim of the exercise is the division of a given territory into functional regions based on travel-to-work flows. Such regions are defined so that a high degree of inter-regional separation and of intra-regional integration in both cases in terms of commuting flows is guaranteed. Additional requirements include the absence of overlap between delineated regions and the exhaustive coverage of the whole territory. The procedure is based on the maximization of a fitness function that measures aggregate intra-region interaction under constraints of inter-region separation and minimum size. In the experimentation stage, two variations of the fitness function are used, and the process is also applied as a final stage for the optimization of the results from one of the most successful existing methods, which are used by the British authorities for the delineation of travel-to-work areas (TTWAs). The empirical exercise is conducted using real data for a sufficiently large territory that is considered to be representative given the density and variety of travel-to-work patterns that it embraces. The paper includes the quantitative comparison with alternative traditional methods, the assessment of the performance of the set of operators which has been specifically designed to handle the regionalization problem and the evaluation of the convergence process. The robustness of the solutions, something crucial in a research and policy-making context, is also discussed in the paper.

Relative Concerns on Visible Consumption: A Source of Economic Distortions

Do relative concerns on visible consumption give rise to economic distortions? We re-examine the question posited by Arrow and Dasgupta (2009) building upon their general framework but recognizing that relative concerns can only apply to visible goods (e.g., cars, clothing, jewelry) and that households consume both visible and non-visible goods. Contrary to Arrow and Dasgupta (2009), the answer to this question turns to be always affirmative: the competitive equilibrium will always be different than the socially optimal one, since individuals do not take into account the negative externality they exert on others through the consumption of the visible good, while the social planner does. If one invokes separability assumptions, then the steady state competitive equilibrium consumption of non-visible goods will be strictly lower than the socially optimal one.

Economics of money and banking /

Gift.

The Bureau of Home Economics : its history, activities and organization /

Includes bibliographical references (p. 87-92).

General agreement between Employee Service and Records Division, Bureau of Retirement, Insurance and Occupational Health, U.S. Civil Service Commission and American Federation of Government Employees Local 2450.

Mode of access: Internet.

Family food consumption in the United States, spring 1942.

"Published as a part of the Study of family spending and saving in wartime, conducted by the Bureau of Human Nurition and Home Economics, Agricultural Research Administration, in cooperation with the United States Bureau of Labor Statistics."

Economics of forestry : a bibliography for the United States and Canada, 1960-1962 /

Includes index.

Maine occupational needs to the year 2000 /

"Issued March 1992."

Summary of the United States and European Union Seminar on the Social Dimension of Economic Integration.

"April 2000."

Wages and related benefits.

Vol. for 1953-1954 has section title: Major labor markets; issued in 3 pts.

Social-Institutional Structures That Matter: An Exploratory Analysis of Sexual/Gender Minority Status and Income in Japan

Thesis (Master's)--University of Washington, 2016-06

Comparison of rural and urban attitudes to the conservation of Asian elephants in Sri Lanka: empirical evidence

There has been little study of economic and general attitudes towards the conservation of the Asian elephant. This paper reports and analyses results from surveys conducted in Sri Lanka of attitudes of urban dwellers and farmers towards nature conservation in general and the elephant conservation in particular. The analyses are based on urban and a rural sample. Contingent valuation techniques are used as survey instruments. Multivariate logit regression analysis is used to analyse the respondents' attitudes towards conservation of elephants. It is found that, although some variations occurred between the samples, the majority of the respondents (both rural and urban) have positive attitudes towards nature conservation in general. However, marked differences in attitudes toward elephant conservation are evident between these two samples: the majority of urban respondents were in favour of elephant conservation; rural respondents expressed a mixture of positive and negative attitudes. Overall, considerable unrecorded and as yet unutilised economic support for conservation of wild elephants exists in Sri Lanka. (C) 2002 Elsevier Science Ltd. All rights reserved.

Policies for saving a rare Australian glider: economics and ecology

This paper considers the economics of conserving a species with mainly non-use value, the endangered mahogany glider. Three serial surveys of Brisbane residents provide data on the knowledge of respondents about the mahogany glider. The results supply information about the attitudes of respondents to the mahogany glider, to its conservation and relevant public policies, and about variations in these factors as the knowledge of participants of the mahogany glider alters. Similarly, data are provided and analysed about the willingness to pay of respondents to conserve the mahogany glider and how it changes. Population viability analysis is applied to estimate the required habitat area for a minimum viable population of the mahogany glider to ensure at least a 95% probability of its survival for 100 years. Places are identified in Queensland where the requisite minimum area of critical habitat can be conserved. Using the survey results as a basis, the likely willingness of groups of Australians to pay for the conservation of the mahogany glider is estimated and consequently their willingness to pay for the minimum required area of its habitat. Methods for estimating the cost of protecting this habitat are outlined. Australia-wide benefits are estimated to exceed the costs. Establishing a national park containing the minimum viable population of the mahogany glider is an appealing management option. This would also be beneficial in conserving other endangered wildlife species and ecosystems. Therefore, additional economic benefits to those estimated on account of the mahogany glider itself can be obtained. (C) 2004 Elsevier Ltd. All rights reserved.