2,125 research outputs found
[Letter] April 25, Kent [to] Dear and Honored Sir / Ch[arles]. Darwin.
No full textThe letter is written on Down / Bromley / Kent, S.C. letterhead. See also other letters in the collection from Charles Darwin.Darwin relates, "At last I have found time to correct the Origin." He states that he has compared the text of the third English edition with the second edition which was translated into German, and has made pencil corrections. "As I am a poor German scholar," Darwin confesses, "it would take me a long time to compare all, but it will lose you very little time." He also discusses "enlarging the part which has been most criticized." Darwin feels "quite doubtful" about the possibility of Mr. Swigerbart[?] translating his book on orchids. He mentions the woodcuts and the possibility of Mr. Murray printing the edition. Darwin\u27s speculations about evolution and natural selection in his _Origin of the Species_ (1859) and _The Descent of Man_ (1871) were published and widely discussed during his lifetime
The systematics and genetics of tomatoes on the Galápagos Islands (Solanum, Solanaceae)
No full textGalápagos tomatoes (Solanum section Lycopersicon) have long interested
scientists and plant breeders. Several morphological and physiological
characters found in the endemic Galápagos tomatoes have been bred into the
cultivated Solanum lycopersicum, making the native plants an invaluable
resource for the development of this important global crop.
Extensive fieldwork was carried out on twelve islands, old records were
confirmed, new records added, but several previously recorded populations of
endemic tomatoes could not be confirmed. I collected tomatoes from 12 islets
and Islands. Detailed morphometric analysis on c.400 plants and extensive
genetic studies on c.1,200 plants were carried out in addition to fieldwork and
natural history studies. Observations and experiments were carried out on
herbarium specimens, field collected and green house grown accessions. I
confirmed the presence of four taxa in the Galápagos Islands – two endemic
species S. cheesmaniae and S. galapagense, the latter here described as new,
and two introduced species S. pimpinellifolium and S. lycopersicum.
Hybrids were found involving all taxa growing in the Galápagos Islands.
Of particular interest is an extensive hybrid zone between S. cheesmaniae and
S. pimpinellifolium spanning 20km along the Baltra Road on Isla Santa Cruz.
Hybridization raises the threat of extinction by introgression and the possibility
of the evolution of a serious invasive species. Conservation recommendations
are proposed.
In addition, a genetic analysis was undertaken of 60 seed bank
accessions of all four tomato species from the Galápagos. Again, indications of
hybridization were found, raising the potential of introgression within the seed
bank collections, occurring potentially during rejuvenation cycles.
Furthermore, I propose a new outline for a generic invasive species
threat/impact scoring system. Applying this new system I class Solanum
pimpinellifolium as an alien invasive species and assess its impact on Isla
Santa Cruz in the Galápagos Islands
Natural Variation of the Circadian Clock in Neurospora
No full textMost living organisms on earth experience daily and expected changes from the rotation of the earth. For an organism, the ability to predict and prepare for incoming stresses or resources is a very important skill for survival. This cellular process of measuring daily time of the day is collectively called the circadian clock. Because of its fundamental role in survival in nature, there is a great interest in studying the natural variation of the circadian clock. However, characterizing the genetic and molecular mechanisms underlying natural variation of circadian clocks remains a challenging task. In this chapter, we will summarize the progress in studying natural variation of the circadian clock in the successful eukaryotic model Neurospora, which led to discovering many design principles of the molecular mechanisms of the eukaryotic circadian clock. Despite the success of the system in revealing the molecular mechanisms of the circadian clock, Neurospora has not been utilized to extensively study natural variation. We will review the challenges that hindered the natural variation studies in Neurospora, and how they were overcome. We will also review the advantages of Neurospora for natural variation studies. Since Neurospora is the model fungal species for circadian study, it represents over 5 million species of fungi on earth. These fungi play important roles in ecosystems on earth, and as such Neurospora could serve as an important model for understanding the ecological role of natural variation in fungal circadian clocks.Advances in Genetics, Vol. 99
Corrigendum to “A generic multi-level framework for microscopic traffic simulation with automated vehicles in mixed traffic” [Transport. Res. Part C: Emerg. Technol. 110 (2020) 291–311] (Transportation Research Part C (2020) 110 (291–311), (S0968090X19304322), (10.1016/j.trc.2019.11.019))
No full textThe authors regret that a contributing author was missing from the list of authors. The complete list of authors should be: “S.C. Calvert, B. van Arem, & J. W. C. van Lint”. All are with Delft University of Technology, Department of Transport & Planning, The Netherlands updated as above. The authors would like to apologise for any inconvenience caused.Transport and Plannin
Towards the Holy Grail: combining system dynamics and discrete-event simulation in healthcare
No full textThe idea of combining discrete-event simulation and system dynamics has been a topic of debate in theoperations research community for over a decade. Many authors have considered the potential benefits ofsuch an approach from a methodological or practical standpoint. However, despite numerous examples ofmodels with both discrete and continuous parameters in the computer science and engineering literature,nobody in the OR field has yet succeeded in developing a genuinely hybrid approach which truly integratesthe philosophical approach and technical merits of both DES and SD in a single model. In this paperwe consider some of the reasons for this and describe two practical healthcare examples of combinedDES/SD models, which nevertheless fall short of the “holy grail” which has been so widely discussed inthe literature over the past decade
Darwin and the sea
No full textAdemás de sus conocidos aportes a la geología, la paleontología y la biogeografía de ecosistemas terrestres de la región pampeana y la Patagonia (Argentina), Darwin realizó notables y poco difundidas contribuciones al conocimiento de los ambientes marinos costeros del actual territorio argentino y de los organismos que habitan en ellos. La intimidad de Darwin con el mar se advierte en toda su obra: en el Viaje y en el Origen igual que en numerosos trabajos de investigación realizados y publicados a su regreso a Inglaterra. Entre 1846 y 1854 dio a conocer una extensa obra sobre cirrípedos o cirripedios, que sentó las bases del estudio de esos crustáceos y, aún hoy, es bibliografía obligada de los taxónomos. Su trabajo sobre la estructura y distribución de los arrecifes coralinos de 1842, es considerado un documento fundacional del conocimiento sobre el origen de los atolones. Los moluscos fueron igualmente objeto de publicaciones y cartas entre 1848 y 1871. La difundida imagen de Darwin sentado ante un escritorio escribiendo sus libros lleva a olvidar que pasaba también mucho tiempo con el microscopio. En el Viaje del Beagle incluyó párrafos sobre aves marinas, lo mismo que sobre briozoos o briozoarios, y en El origen, explicó sus pensamientos acerca de la migración de los ojos en los lenguados. Dedicó especial atención a las algas gigantes o sargazos marinos de Tierra del Fuego (donde se los conoce por cachiyuyos). Se incluyen los siguientes trabajos de divulgación científica -Darwin y los briozoos; -Darwin y el desarrollo larval de crustáceos; -Sobre Cirripedios; De Darwin a los acelerómetros; -Los peces de cara torcida; -La incursión en la costa sur de Buenos Aires.Reprinted as: pp.145-154 in, Ciencia del Mar. Volumen temático 1, 12/2014; Asociación Ciencia Hoy. ISBN: 978-987-45584-0-4 (Special issue dedicated to 'Marine Sciences: 1988-2014'
Hybrid simulation for health and social care: the way forward, or more trouble than it’s worth?
No full textDarwin y el mar
No full textAdemás de sus conocidos aportes a la geología, la paleontología y la biogeografía de ecosistemas terrestres de la región pampeana y la Patagonia (Argentina), Darwin realizó notables y poco difundidas contribuciones al conocimiento de los ambientes marinos costeros del actual territorio argentino y de los organismos que habitan en ellos. La intimidad de Darwin con el mar se advierte en toda su obra: en el Viaje y en el Origen igual que en numerosos trabajos de investigación realizados y publicados a su regreso a Inglaterra. Entre 1846 y 1854 dio a conocer una extensa obra sobre cirrípedos o cirripedios, que sentó las bases del estudio de esos crustáceos y, aún hoy, es bibliografía obligada de los taxónomos. Su trabajo sobre la estructura y distribución de los arrecifes coralinos de 1842, es considerado un documento fundacional del conocimiento sobre el origen de los atolones. Los moluscos fueron igualmente objeto de publicaciones y cartas entre 1848 y 1871. La difundida imagen de Darwin sentado ante un escritorio escribiendo sus libros lleva a olvidar que pasaba también mucho tiempo con el microscopio. En el Viaje del Beagle incluyó párrafos sobre aves marinas, lo mismo que sobre briozoos o briozoarios, y en El origen, explicó sus pensamientos acerca de la migración de los ojos en los lenguados. Dedicó especial atención a las algas gigantes o sargazos marinos de Tierra del Fuego (donde se los conoce por cachiyuyos). Se incluyen los siguientes trabajos de divulgación científica -Darwin y los briozoos; -Darwin y el desarrollo larval de crustáceos; -Sobre Cirripedios; De Darwin a los acelerómetros; -Los peces de cara torcida; -La incursión en la costa sur de Buenos Aires
Waste and innovation. How waste companies and government can interact to stimulate innovation in the Dutch waste industry
No full textThis thesis answers the question how government and Dutch waste companies can interact in such a way that innovation is stimulated. The author has developed a method to determine the potential for self-regulation and self-control of a company or an industry. This method is based upon the measurement of degree to which the company has assured legal compliance within the own organisation. Furthermore an approach is given to create innovation-friendly regulation using innovation theoretical principles.Industrial Design Engineerin
Policy analysis of water management for the Netherlands. Vol VII: Assessment of impacts on drinking-water companies and their customers
No full textThis volume assesses the impacts of a number of water management policies developed by PAWN on drinking-water (DW) companies and their customers (households, commercial entities, and industrial firms). Chapter 2 summarizes briefly the major water-related problems facing DW companies in the Netherlands today, and shows why the author believes they will become more severe in the future. Chapter 3 describes the methodology in detail. Chapter 4 presents the impacts and associated discussion of PAWN's primary and groundwater cases on DW production, and on DW companies and their customers. Finally, in Chap. 5, the author assesses those impacts, draws some overall conclusions, and discusses the implications of those conclusions for the future supply and costs of DW in the Netherlands.PAW
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