The emergence of environmental homeostasis in complex ecosystems

The Earth, with its core-driven magnetic field, convective mantle, mobile lid tectonics, oceans of liquid water, dynamic climate and abundant life is arguably the most complex system in the known universe. This system has exhibited stability in the sense of, bar a number of notable exceptions, surface temperature remaining within the bounds required for liquid water and so a significant biosphere. Explanations for this range from anthropic principles in which the Earth was essentially lucky, to homeostatic Gaia in which the abiotic and biotic components of the Earth system self-organise into homeostatic states that are robust to a wide range of external perturbations. Here we present results from a conceptual model that demonstrates the emergence of homeostasis as a consequence of the feedback loop operating between life and its environment. Formulating the model in terms of Gaussian processes allows the development of novel computational methods in order to provide solutions. We find that the stability of this system will typically increase then remain constant with an increase in biological diversity and that the number of attractors within the phase space exponentially increases with the number of environmental variables while the probability of the system being in an attractor that lies within prescribed boundaries decreases approximately linearly. We argue that the cybernetic concept of rein control provides insights into how this model system, and potentially any system that is comprised of biological to environmental feedback loops, self-organises into homeostatic states

Tipping points in complex coupled life-environment systems

Simple models of complex phenomena provide powerful insights and suggest low-level mechanistic descriptions. The Earth system arises from the interaction of subsystems with multi-scale temporal and spatial variability; from the microbial to continental scales, operating over the course of days to geological time. System-level homeostasis has been demonstrated in a number of conceptual, artificial life, models which share the advantage of a thorough and transparent analysis. We reintroduce a general model for a coupled life-environment model, concentrating on a minimal set of assumptions, and explore the consequences of interaction between simple life elements and their shared, multidimensional environment. In particular stability, criticality and transitions are of great relevance to understanding the history, and future of the Earth system. The model is shown to share salient features with other abstract systems such as Ashby's Homeostat and Watson and Lovelock's Daisyworld. Our generic description is free to explore high-dimensional, complex environments, and in doing so we show that even a small increase in the environmental complexity gives rise to very complex attractor landscapes which require a much richer conception of critical transitions and hysteresi

Questions and Answers on Anthrax Prevention and Treatment in South Dakota

In this circular, created by the Agriculture Extension Service at South Dakota State College, the information provided includes how to prevent and treat anthrax within the boundaries of one’s farm. This information is provided through the guidance of the Agriculture Department during the year 1938

Farm Sanitation

Sanitation means to keep things clean, to be hygienic. Farm sanitation helps to preserve the health of domestic animals and indirectly the health of the people that live on the farm. Cleanliness, sunlight, fresh air and disinfectants are the important fact1ors in sanitation

Introduction: Tricksters, humour and activism

This special issue, entitled ‘The Trickster Activist in Global Humour and Comedy’, investigates the relevance of the concept of the trickster for explaining activist expressions that emanate from comedians, or that appear in comedy and humour more generally. Comedy has traditionally been viewed as an aesthetic or entertainment medium. It has often been charged with encouraging stereotype and the affirmation of mainstream audience beliefs. Despite this, we argue, there have been moments in recent history where comedians have given their performances an increased level of social and political consciousness that resonates with the public at large, or with sections of the public. Comedians, we argue, are able to reach this level of social commentary due to their potential to become tricksters. Paradoxically, the mythical trickster is a liminal entity, one that is adept at destruction as well as creation, or at conservativism as well radicalism. The articles in this issue explore the complexity of the trickster concept, showing some of the polysemy involved in the social activism enabled by comedy and humour

Aims and Aids for Girls and Young Women on the Various Duties of Life

In the preface, the author states that, Society does little else than to teach its girls to be dolls and drudges, and that his purpose in the book is to give some suggestions as to how women\u27s education should be improved so that women could fulfill their true potential. The various duties of life referenced in the title and which are the subjects of the fourteen lectures of the book include: physical, intellectual, and moral elopement; self-culture, improvement, dress, beauty, fashion, employment, education, the home relations, their duties to young men, marriage, womanhood, and happiness.https://openworks.wooster.edu/motherhomeheaven/1055/thumbnail.jp

The reprocessing features in the X-ray spectrum of the NELG MCG-5-23-16

We present results from the spectral analysis of the Seyfert 1.9 galaxy MCG-5-23-16, based on ASCA, BeppoSAX, Chandra and XMM-Newton observations. The spectrum of this object shows a complex iron Kalpha emission line, which is best modeled by a superposition of a narrow and a broad (possibly relativistic) iron line, together with a Compton reflection component. Comparing results from all (six) available observations, we do not find any significant variation in the flux of both line components. The moderate flux continuum variability (about 25% difference between the brightest and faintest states), however, does not permit us to infer much about the location of the line-emitting material. The amount of Compton reflection is lower than expected from the total iron line EW, implying either an iron overabundance or that one of the two line components (most likely the narrow one) originates in Compton-thin matter.Comment: Accepted for publication in A&

The importance of timescales for the emergence of environmental self-regulation

Models which explore the possibilities of emergent self-regulation in the Earth system often assume the timescales associated with changes in various sub-systems to be predetermined. Given their importance in guiding the fixed point dynamics of such models, relatively little formalism has been established. We analyse a classic model of environmental self-regulation, Daisyworld, and interpret the original equations for model temperature, changes in insolation, and self-organisation of the biota as an important separation of timescales. This allows a simple analytical solution where the model is reduced to two states while retaining important characteristics of the original model. We explore the consequences of relaxing some key assumptions. We show that increasing the rate of change of insolation relative to adaptation of the biota shows a sharp transition between regulating, and lifeless states. Additionally, in slowing the rate of model temperature change relative to the adapting biota we derive expressions for the damping rate of fluctuations, along with a threshold beyond which damped oscillations occur. We relax the assumption that seeding occurs globally by extending this analysis to solve a two-dimensional cellular automata Daisyworld. We conclude by reviewing a number of previous Daisyworld models and make explicit their respective timescales, and how their behaviour can be understood in light of our analysi

Causes of and alternatives to medication for behaviours that challenge in people with intellectual disabilities: direct care providers' perspectives

Behaviours that challenge (BtC), such as aggression and self-injury, are manifested by many people with intellectual disabilities (ID). National and international guidelines recommend non-pharmacological psychosocial intervention before considering medication to address BtC. Support staff play a pivotal role in the prescription process. Using coproduction, we developed a training programme for support staff, called SPECTROM, to give them knowledge and empower them to question inappropriate prescriptions and ask for the discontinuation of medication if appropriate and instead look for ways to help people with ID when they are distressed without relying on medication. We have presented data from two focus groups that we conducted during the development of SPECTROM: one that included support staff, and another that had service managers and trainers. In these focus groups, we explored participants’ views on the use of medication to address BtC with a particular emphasis on the causes of and alternatives to medication for BtC. Along with the participants’ views, we have also presented how we have addressed these issues in the SPECTROM resources

Turkey Production in South Dakota

The turkey is truly an American bird and suggests not only Thanksgiving to Americans but America itself to the world. The Cyclopedia of Agriculture comments that America has furnished but few domestic animals and mentions the llama of South America, the turkey, and the bison as a third possible example