Artificial Soil Formation And Stabilization Of Material Cycles In Closed Ecological Systems For Mars Habitats

Scientists are increasingly pressured to investigate novel ways in which to feed astronauts for the first mission to Mars in the 2030s. It is the aim of this thesis to conduct a preliminary investigation for soil formation of NASA JSC Mars-1A Regolith Simulant in an environmentally closed ecosystem to simulate plant growth within these initial habitats, and the prospect of soil formation from a Mars parent material for agricultural purposes. The rhizosphere and plant stress will be the main regions of research focus. It is hypothesized rhizosphere activity will determine the rate of stable soil formation adequate to support the agricultural needs of Mars\u27s first human inhabitants. A Brassica rapa (Wisconsin FastPlantTM) was grown on several different substrates, and evaluated for plant stress, elemental analysis, soil fertility, and mineralogical analysis to identify the biogeochemical factors related to areas inside and outside of the rhizosphere, which affect soil formation. In addition, multiple plant generations were grown to investigate bioavailability of nutrients within the system, and lay down preliminary approaches for mathematical model development in order to predict & evaluate future conditions and applications under reduced resource availability situations. Overall, the story of early soil formation from a Mars regolith simulant is further defined to aid in the success of our first human adventurers to the red planet

Numerical comparison between a Gyrofluid and Gyrokinetic model investigating collisionless magnetic reconnection

The first detailed comparison between gyrokinetic and gyrofluid simulations of collisionless magnetic reconnection has been carried out. Both the linear and nonlinear evolution of the collisionless tearing mode have been analyzed. In the linear regime, we have found a good agreement between the two approaches over the whole spectrum of linearly unstable wave numbers, both in the drift kinetic limit and for finite ion temperature. Nonlinearly, focusing on the small-$\Delta '$ regime, with $\Delta '$ indicating the standard tearing stability parameter, we have compared relevant observables such as the evolution and saturation of the island width, as well as the island oscillation frequency in the saturated phase.The results are basically the same, with small discrepancies only in the value of the saturated island width for moderately high values of $\Delta '$. Therefore, in the regimes investigated here, the gyrofluid approach can describe the collisionless reconnection process as well as the more complete gyrokinetic model.Comment: Accepted for publication on Physics of Plasma

Toner ink particle morphology in air-sparged hydrocyclone flotation deinking

Journal ArticleA series of pulping and flotation deinking tests were performed using a pilot-scale air-sparged hydrocyclone (ASH) flotation cell and a toner ink printed furnish. Microscopy studies indicate ink particles in both the flotation accepts and rejects are relatively flat. Many of the ink particles appear to be brittle and easily broken into smaller fragments. In some cases, toner ink particle softening had occurred as indicated by partial fusion of ink particles. Despite this softening, environmental scanning electron microscope (ESEM) images suggest toner ink particles were not elongated by the high shear conditions associated with the airsparged cyclone flotation cell

Architecture reconnected: the hybrid urbanisation of the physical space and the digital space of Johannesburg

In the rapid technological urbanisation of the built fabric of the city during the 21st century it has changed the way we engage spaces within the city. It has had both a positive and negative effect on existing social structures. The more digitally reliant society becomes the more essential the role of architecture and infrastructure networks become. The city is plugged in. The young tech savvy generations have become consumed by technology in the era of mobile phones, tablets and personal computers while the older generations can feel overwhelmed or even rejected by the new technologically orientated processes and functions of the city. The city has become a network of information exchange; environments of high technical performance and reliance. This has created labour and work environments that require a more skilled work force with digital comprehension and technical proficiency. It calls for an education system that includes advance digital literacy as part of basic education requirements to make students well equipped in a technological utopian state of living (Teletopia). In the context of Johannesburg, South Africa, with our diverse cultures and beliefs we struggle with both past and new social inequalities. In the telecommunication global village technology has no bias for race, age or culture if you are not technically proficient you are rejected and left behind. The permanence of architecture gives it strength and integrity. The solidity of concrete, brick, steel and building materials that are assembled aid to the capacity to withstand loads and stresses. A built form that responds to contextual issues and the resolution of construction details that collectively makes for good design. The integration of technology within architecture calls designers to question its value it will add to the spaces created to the initial capital costs. Would a more technological orientated education system be able to address the issues of schooling in South Africa today? Will technical solutions reach students who can’t afford the high cost of education, the shortage of quality teachers or the struggle to get text books to schools and liberate the school of the timetable and the availability of teachers? The role of technology in both schools and architecture will be determined by the demands of society. The internet is an agent like fire and water only given direction and purpose by those who use it. The true influence will how it will encourage spaces in schools to become more fluid and adaptable which will encourage accidental learning and peer-to-peer learning environments. The role of schools is vital to the social development of the younger generation. They are more than just academic institutions but become community catalysts for the areas they serve. The more technical savvy generation growing up today have become a lot more self-absorbed with Facebook and other social media making the youth more concerned about the way other people perceive them. This makes the role of schools even more important to not only prepare students with the relevant technical skills required to engage the digital “Teletopian” city they live in but to develop the social skills that allows them to engage the physical environments of the city too. Society has drawn to technological advancements like a moth to a light bulb but no matter how technologically orientated we become we will always be tangible beings who need physical interaction with the spaces we appropriate from our homes, offices and schools

Emergent spatial patterns of competing benthic and pelagic algae in a river network: A parsimonious basin-scale modeling analysis

Algae, as primary producers in riverine ecosystems, are found in two distinct habitats: benthic and pelagic algae typically prevalent in shallow/small and deep/large streams, respectively. Over an entire river continuum, spatiotemporal patterns of the two algal communities reflect specificity in habitat preference determined by geomorphic structure, hydroclimatic controls, and spatiotemporal heterogeneity in nutrient loads from point- and diffuse-sources. By representing these complex interactions between geomorphic, hydrologic, geochemical, and ecological processes, we present here a new river-network-scale dynamic model (CnANDY) for pelagic (A) and benthic (B) algae competing for energy and one limiting nutrient (phosphorus, P). We used the urbanized Weser River Basin in Germany (7th-order; ~8.4 million population; ~46 K km2) as a case study and analyzed simulations for equilibrium mass and concentrations under steady median river discharge. We also examined P, A, and B spatial patterns in four sub-basins. We found an emerging pattern characterized by scaling of P and A concentrations over stream-order ω, whereas B concentration was described by three distinct phases. Furthermore, an abrupt algal regime shift occurred in intermediate streams from B dominance in ω≤3 to exclusive A presence in ω≥6. Modeled and long-term basin-scale monitored dissolved P concentrations matched well for ω>4, and with overlapping ranges in ω<3. Power-spectral analyses for the equilibrium P, A, and B mass distributions along hydrological flow paths showed stronger clustering compared to geomorphological attributes, and longer spatial autocorrelation distance for A compared to B. We discuss the implications of our findings for advancing hydro-ecological concepts, guiding monitoring, informing management of water quality, restoring aquatic habitat, and extending CnANDY model to other river basins

Beef Cattle Marketing Alliances

4 pp.This leaflet focuses on the three kinds of beef carcass alliances: breed association-sponsored; commercial; and natural/implant-free. Each is intended to help producers make their operations more profitable. In the long run, producers are advised to maintain flexibility in their herds and learn all they can about different pricing structures

River water quality model no. 1 (RWQM1): II. Biochemical process equations

In this paper, biochemical process equations are presented as a basis for water quality modelling in rivers under aero-bic and anoxic conditions. These equations are not new, but they summarise parts of the development over the past 75 years. The primary goals of the presentation are to stimulate communication among modellers and field-oriented researchers of river water quality and of wastewater treatment, to facilitate practical application of river water quality modelling, and to encourage the use of elemental mass balances for the derivation of stoichiometric coefficients of biochemical transformation processes. This paper is part of a series of three papers: In the first paper, the general modelling approach is described; in the present paper, the biochemical process equations of a complex model are presented; and in the third paper, recommendations are given for the selection of a reasonable submodel for a specific application

Glucose concentration in capillary blood of dairy cows obtained by a minimally invasive lancet technique and determined with three different hand-held devices

Background Dairy cows have a massive demand for glucose at the onset of lactation. A poor adaption to this period leads to an excessive negative energy balance with an increased risk for ketosis and impaired animal health and production. Besides the measurement of ketones, analysing the glucose concentration in blood is reported as helpful instrument for diagnosis and differentiation of ketosis. Monitoring metabolic parameters requires multiple blood sampling. In other species, new blood sampling techniques have been introduced in which small amounts of blood are rapidly analysed using electronic hand-held devices. The objective of this study was to evaluate the suitability of capillary blood for blood glucose measurement in dairy cows using the hand-held devices FreeStyle Precision (FSP, Abbott), GlucoMen LX Plus (GLX, A. Menarini) and the WellionVet GLUCO CALEA, (WGC, MED TRUST). In total, 240 capillary blood samples were obtained from dry and fresh lactating Holstein-Friesian cows. Blood was collected from the skin of the exterior vulva by using a lancet. For method comparison, additional blood samples were taken from a coccygeal vessel and analyzed in a laboratory. Glucose concentrations measured by a standard laboratory method were defined as the criterion standard. Results The Pearson correlation coefficients between the glucose concentrations analyzed in capillary blood with the devices and the reference were 73 % for the FSP, 81 % for the GLX and 41 % for the WGC. Bland- Altman plots showed biases of −18.8 mg/dL for the FSP, -11.2 mg/dL for the GLX and +20.82 mg/dL for the WGC. The optimized threshold determined by a Receiver Operating Characteristics analysis to detect hyperglycemia using the FSP was 43 mg/dL with a sensitivity (Se) and specificity (Sp) of 76 and 80 %. Using the GLX and WGC optimized thresholds were 49 mg/dL (Se = 92 %, Sp = 85 %) and 95 mg/dL (Se = 39 %, Sp = 92 %). Conclusions The results of this study demonstrate good performance characteristics for the GLX and moderate for the FSP to detect hyperglycemia in dairy cows using capillary blood. With the study settings, the WGC was not suitable for determination of glucose concentrations

Zeros of the i.i.d. Gaussian power series: a conformally invariant determinantal process

Consider the zero set of the random power series f(z)=sum a_n z^n with i.i.d. complex Gaussian coefficients a_n. We show that these zeros form a determinantal process: more precisely, their joint intensity can be written as a minor of the Bergman kernel. We show that the number of zeros of f in a disk of radius r about the origin has the same distribution as the sum of independent {0,1}-valued random variables X_k, where P(X_k=1)=r^{2k}. Moreover, the set of absolute values of the zeros of f has the same distribution as the set {U_k^{1/2k}} where the U_k are i.i.d. random variables uniform in [0,1]. The repulsion between zeros can be studied via a dynamic version where the coefficients perform Brownian motion; we show that this dynamics is conformally invariant.Comment: 37 pages, 2 figures, updated proof