Evaluating watershed management projects:

Watershed projects play an increasingly important role in managing soil and water resources throughout the world. Research is needed to ensure that new projects draw upon lessons from their predecessors' experiences. However, the technical and social complexities of watershed projects make evaluation difficult. Quantitative and qualitative evaluation methods, which traditionally have been used separately, both have strengths and weaknesses. Combining them can make evaluation more effective, particularly when constraints to study design exist. This paper presents mixed-methods approaches for evaluating watershed projects. A recent evaluation in India provides illustrations.

High Performance Computing of Gene Regulatory Networks using a Message-Passing Model

Gene regulatory network reconstruction is a fundamental problem in computational biology. We recently developed an algorithm, called PANDA (Passing Attributes Between Networks for Data Assimilation), that integrates multiple sources of 'omics data and estimates regulatory network models. This approach was initially implemented in the C++ programming language and has since been applied to a number of biological systems. In our current research we are beginning to expand the algorithm to incorporate larger and most diverse data-sets, to reconstruct networks that contain increasing numbers of elements, and to build not only single network models, but sets of networks. In order to accomplish these "Big Data" applications, it has become critical that we increase the computational efficiency of the PANDA implementation. In this paper we show how to recast PANDA's similarity equations as matrix operations. This allows us to implement a highly readable version of the algorithm using the MATLAB/Octave programming language. We find that the resulting M-code much shorter (103 compared to 1128 lines) and more easily modifiable for potential future applications. The new implementation also runs significantly faster, with increasing efficiency as the network models increase in size. Tests comparing the C-code and M-code versions of PANDA demonstrate that this speed-up is on the order of 20-80 times faster for networks of similar dimensions to those we find in current biological applications

Evidence for the role of proteoglycans in cation-mediated gene transfer

We report evidence that gene complexes, consisting of polycations and plasmid DNA enter cells via binding to membrane-associated proteoglycans. Treatment of HeLa cells with sodium chlorate, a potent inhibitor of proteoglycan sulfation, reduced luciferase expression by 69%. Cellular treatment with heparinase and chondroitinase ABC inhibited expression by 78% and 20% with respect to control cells. Transfection was dramatically inhibited by heparin and heparan sulfate and to a smaller extent by chondroitan sulfate B. Transfection of mutant, proteoglycan deficient Chinese hamster ovary cells was 53 x lower than of wild-type cells. For each of these assays, the intracellular uptake of DNA at 37 degrees C and the binding of DNA to the cell membrane at 4 degrees C was impaired. Preliminary transfection experiments conducted in mutant and wild-type Chinese hamster ovary cells suggest that transfection by some cationic lipids is also proteoglycan dependent. The variable distribution of proteoglycans among tissues may explain why some cell types are more susceptible to transfection than others

Getting the message: The adaptive potential of interpersonal judgments

According to the Social Message Model, interpersonal judgments are transactions in which judges convey important social messages to the individuals they evaluate (the targets); targets can then respond to the judgments in more or less adaptive ways. We argue that judges’ opinions emerge from their current concerns, be it to promote their own well-being, or to foster group cohesion. Targets of judgments can best interpret the meaning of a judgment they receive by understanding the judge’s concerns, competence of the judge, and other qualities of the transaction. We suggest that judges and targets who are better able to reason about the judgment process are likely to change their behaviors more adaptively than people less able to reason in this area

Narratives of Diversity in the Corporate Boardroom: What Corporate Insiders Say About Why Diversity Matters

Over the last generation, the concept of diversity has become commonplace and taken-for-granted in discourses ranging from law to education to business. In higher education, for example, it is hard to imagine a faculty job search or a student admissions discussion that was not heavily laden with talk of diversity, in the sense of the representative inclusion of women and racial and ethnic minorities in a group or organization. In this paper we present the results of an interview-based study of the discourse of diversity in a particular business setting: the corporate boardroom. Our principal observation is that—thirty-one years after the Supreme Court’s Bakke decision introduced the term into public discourse--corporate insiders appear not to have arrived at a master narrative to explain the pursuit of diversity on boards of directors. Instead, their accounts stress a variety of factors and feature few concrete examples

Dangerous Categories: Narratives of Corporate Board Diversity

In this article, we report the results of a series of interviews with corporate directors about racial, ethnic, and gender diversity on corporate boards. On the one hand, our respondents were clear and nearly uniform in their statements that board diversity was an important goal worth pursuing. Yet when asked to provide examples or anecdotes illustrating why board diversity matters, many subjects acknowledged difficulty in illustrating theory with reference to practice. This expressed reluctance to come to specific terms with general claims about the value of director diversity inspired our title phrase: dangerous categories. That is, while diversity evokes universal acclaim in the abstract, our respondents’ narratives demonstrate that it is an elusive and even dangerous subject to talk about concretely. So we are left with narratives that simultaneously extol difference and express embarrassment with it.This expressed reluctance to come to specific terms with general claims about the value of director diversity inspired our title phrase: dangerous categories. That is, while diversity evokes universal acclaim in the abstract, our respondents’ narratives demonstrate that it is an elusive and even dangerous subject to talk about concretely. So we are left with narratives that simultaneously extol difference and express embarrassment with it

Preparing Leaders in Public Health for Success in a Flatter, More Distributed and Collaborative World

In a world that is rapidly changing, what are the challenges for which leaders in public health in the future need to be prepared, what are the qualities and skills they will need for success, and where will they get the training they require? Addressing each of these questions in succession, this article contends that success in a flatter, more distributed and collaborative world will require a new generation of leaders in public health with new mindsets, an appetite for innovation and interdisciplinary collaboration and a strong dose of political savvy. Faculty, curricula and com­petencies in academic centers play an important role in this equation

Differential Effects Rail Deregulation in the U.S. Grain Industry

The efficiency benefits of U.S. rail industry deregulation are well documented in previous studies of rail productivity and declining rail rates. This research provides new insight regarding the accrual of these benefits within the grain industry. A disaggregate study of corn, wheat, and soybean rates across nine producing regions, shows that in recent years the railroads ability to differentiate markets based on competitive environment has shifted relatively more of the benefit to regions with the most competitive market environments. Regions with less competitive pressure will continue to be relatively more disadvantaged in the rates that are an important determinant in grain market flows and producer profitability if these trends continue.Marketing, Public Economics,

Estimating sample-specific regulatory networks

Biological systems are driven by intricate interactions among the complex array of molecules that comprise the cell. Many methods have been developed to reconstruct network models of those interactions. These methods often draw on large numbers of samples with measured gene expression profiles to infer connections between genes (or gene products). The result is an aggregate network model representing a single estimate for the likelihood of each interaction, or "edge," in the network. While informative, aggregate models fail to capture the heterogeneity that is represented in any population. Here we propose a method to reverse engineer sample-specific networks from aggregate network models. We demonstrate the accuracy and applicability of our approach in several data sets, including simulated data, microarray expression data from synchronized yeast cells, and RNA-seq data collected from human lymphoblastoid cell lines. We show that these sample-specific networks can be used to study changes in network topology across time and to characterize shifts in gene regulation that may not be apparent in expression data. We believe the ability to generate sample-specific networks will greatly facilitate the application of network methods to the increasingly large, complex, and heterogeneous multi-omic data sets that are currently being generated, and ultimately support the emerging field of precision network medicine