Soil Governance: Accessing Cross-Disciplinary Perspectives

Soil provides the foundation for agricultural and environmental systems, and are subject to a complex governance regime of property rights and secondary impacts from industry and domestic land use. Complex natural resource management issues require approaches to governance that acknowledge uncertainty and complexity. Theories of next generation environmental governance assume that inclusion of diverse perspectives will improve reform directions and encourage behaviour change. This paper reports on a qualitative survey of an international workshop that brought together cross-disciplinary perspectives to address the challenges of soil governance. Results reveal the challenges of communicating effectively across disciplines. The findings suggest that strategies for improved soils governance must focus on increasing communications with community stakeholders and engaging land managers in designing shared governance regimes. The need for more conscious articulation of the challenges of cross-disciplinary environments is discussed and strategies for increasing research collaboration in soils governance are suggested. The identified need for more systematic approaches to cross-disciplinary learning, including reporting back of cross-disciplinary initiatives to help practitioners learn from past experience, forms part of the rationale for this paper

Correlation structures in applied probability

This thesis examines consequences of correlation structure in three areas of applied probability: mathematical population genetics, birth processes, and "exchangeable" measures on distributive lattices. The first three chapters concern probabilistic models in genetics. Initially we generalize the Moran model to allow more than one individual to reproduce per generation, investigating the effect of this on the behaviour of the model. The conclusion is that while things apparently happen faster, the basic properties are the same. This model also serves to unify conventional neutral theory, as it links the Moran model to the Wright-Fisher model. We then consider aspects of the neutral theory. Commonly a neutral model is supposed in which successive generations behave independently. This may well be unrealistic. Here we take the Moran model and adapt it to allow for correlations in offspring numbers between generations. An analysis of the model shows that the conditional distribution of allele frequencies is unchanged, although the expected number of alleles present decreases. Similar results are also obtained when correlation is introduced to the more general model with more than one reproducer per generation. In each case the approach involves a detailed study of the genealogy of the models. Next we consider the effect of correlation in Markov Birth Processes. We show that if the birth rates form a super(sub) linear sequence then the sizes of its families are positively(negatively) correlated. From this we prove a conjecture of Faddy which says that if the birth rates of a process X(t) are super(sub)-linear then the variance ratio V (t) (defined as VarX(t)/(EX(t)[EX(t)/X(0)-1])) is greater than (less than) 1. Finally we study correlation inequalities. The FKG Inequality is a well known result giving sufficient conditions for positive correlations in probability measures on distributive lattices. There are few analogous results concerning negative correlation. We give sufficient conditions for a particular form of negative correlation when the underlying distributions possess a certain exchangeability property

Graywater research findings at the residential level

2014 Spring.Includes bibliographical references.As populations continue to grow and water supply sources become more stressed, innovative means for reducing our reliance on municipal water are becoming more prevalent. Graywater reuse is one water conservation practice which has the potential of reducing household water demands by 30% indoors and outdoors, depending upon irrigation demands. In areas where water scarcity is an ongoing challenge, implementation of graywater reuse practices is becoming more widely accepted. However, constituents commonly found in graywater may pose a threat to the environment or human health. The objective of this thesis is to present graywater research findings from 2003 to the present which have occurred as part of a graywater research program at Colorado State University. The research findings address issues and concerns raised regarding graywater and present the case for graywater reuse being a viable safe, simple and economical technology. In order for graywater reuse applications to continue to expand, the concerns regarding public health risks raised by regulating agencies and public health officials need to be fully addressed. Early research on a residential pilot graywater system for outdoor irrigation formed the foundation for more recent research targeting effects on soil quality (chemistry and microbiology), plant health, groundwater contamination, graywater quality and potential human health risks (Sharvelle, 2009, Shogbon, 2010, Neghaban-Azar, 2012). An optimal residential graywater system prototype for drip irrigation has been developed (Alkhatib, 2008) which includes two tanks, one for collection, coarse filtration and settling and the other for usable storage. The WERF study (Sharvelle et al., 2012) showed no need for disinfection of graywater being used for irrigation. The presence and levels of pathogens on field sites whether being irrigated with either municipal water or graywater were the same. The WERF research (Sharvelle et al., 2012) coupled with the prototype configuration supports no need for inclusion of disinfection as part of the treatment train when graywater is being applied for irrigation. The most recent research is a multi-residential graywater reuse demonstration project for toilet flushing completed on Colorado State University campus, Aspen Hall (Hodgson, 2012). Graywater used for toilet flushing will require a higher level of treatment due to the increased potential for exposure. Hodgson studied and selected Chlorine as the disinfectant for the residence hall. The resulting water quality with storage, filtration and disinfection determined by Hodgson achieves similar results as found in the 2003 residential pilot graywater system research which used UV rather than chlorine. The difficulty of navigating the varying graywater regulations between states drove Glenn's research (2012) into the graywater requirements for each state and who developed a tool for use by regulators to homeowners for finding an appropriate graywater technology to meet their local requirements. Also, a need was identified for providing a comprehensive guidance manual for separating graywater from blackwater for graywater reuse (Bergdolt, 2011). The manual provides design guidance and maintenance best management practices to ensure safe and appropriate graywater installation and operation

Using magnets and magnetic beads to dissect signaling pathways activated by mechanical tension applied to cells

Cellular tension has implications in normal biology and pathology. Membrane adhesion receptors serve as conduits for mechanotransduction that lead to cellular responses. Ligand-conjugated magnetic beads are a useful tool in the study of how cells sense and respond to tension. Here we detail methods for their use in applying tension to cells and strategies for analyzing the results. We demonstrate the methods by analyzing mechanotransduction through VE-cadherin on endothelial cells using both permanent magnets and magnetic tweezers

Mutational signatures in colon cancer.

ObjectiveRecently, many tumor sequencing studies have inferred and reported on mutational signatures, short nucleotide patterns at which particular somatic base substitutions appear more often. A number of signatures reflect biological processes in the patient and factors associated with cancer risk. Our goal is to infer mutational signatures appearing in colon cancer, a cancer for which environmental risk factors vary by cancer subtype, and compare the signatures to those in adult stem cells from normal colon. We also compare the mutational signatures to others in the literature.ResultsWe apply a probabilistic mutation signature model to somatic mutations previously reported for six adult normal colon stem cells and 431 colon adenocarcinomas. We infer six mutational signatures in colon cancer, four being specific to tumors with hypermutation. Just two signatures explained the majority of mutations in the small number of normal aging colon samples. All six signatures are independently identified in a series of 295 Chinese colorectal cancers