New Producer Strategies: The Emergence of Patron-Driven Entrepreneurship

Abstract—Existing research treats the cooperative structure as relatively homogeneous. The proposed paper argues that all cooperatives are not created equal – and consideration of organizational structure is critical when analyzing the economic impact of cooperation. In recent empirical work, we observe cooperatives forming as single- or multi-purpose; generating equity capital passively, quasi-passively, or proactively; vertically integrating in a centralized, federated, or a hybrid fashion; governing through fixed or proportional control rights; and instituting open, closed or class-varying membership criteria. The emergence of multiple-level rent-seeking cooperatives challenges our traditional rent dispersion models of collective action. We call these multi-level, patron, rent-seeking entities a form of collective entrepreneurship. This paper develops a set of criteria enabling us to distinguish between traditional forms of cooperation and collective entrepreneurship. We employ these characteristics to analyze and contrast these two extreme forms of collective action. We propose a continuum from single-level rent seeking, traditional, patron, user-driven cooperative forms; through forms of hybrids and macrohierarchies; to multiple-level rent seeking, patron, user-investor-driven collective entrepreneurship.Collective entrepreneurship, Agribusiness, Property Rights, Agribusiness,

Study of the Growth of Entropy Modes in MSSM Flat Directions Decay: Constraints on the Parameter Space

We study how the resonant decay of moduli fields arising in the Minimal Supersymmetric Standard Model (MSSM) could affect large scale curvature perturbations in the early universe. It has been known for some time that the presence of entropy perturbations in a multi-component system can act as seeds for the curvature perturbations on all scales. These entropy perturbations could be amplified exponentially if one of the moduli decays via stochastic resonance, affecting the curvature power spectrum in the process. By imposing the COBE normalization on this power spectrum, one could put constraints on the masses and couplings of the underlying particle physics model without having to rely on collider experiments. We discuss in detail the case of the MSSM but this method could be applied to other theories beyond the Standard Model.Comment: 6 pages, 1 figure, revtex4, comments added in section II, 1 reference adde

Functional microRNA high throughput screening reveals miR-9 as a central regulator of liver oncogenesis by affecting the PPARA-CDH1 pathway

Background: Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths, reflecting the aggressiveness of this type of cancer and the absence of effective therapeutic regimens. MicroRNAs have been involved in the pathogenesis of different types of cancers, including liver cancer. Our aim was to identify microRNAs that have both functional and clinical relevance in HCC and examine their downstream signaling effectors. Methods: MicroRNA and gene expression levels were measured by quantitative real-time PCR in HCC tumors and controls. A TargetScan algorithm was used to identify miR-9 downstream direct targets. Results: A high-throughput screen of the human microRNAome revealed 28 microRNAs as regulators of liver cancer cell invasiveness. MiR-9, miR-21 and miR-224 were the top inducers of HCC invasiveness and also their expression was increased in HCC relative to control liver tissues. Integration of the microRNA screen and expression data revealed miR-9 as the top microRNA, having both functional and clinical significance. MiR-9 levels correlated with HCC tumor stage and miR-9 overexpression induced SNU-449 and HepG2 cell growth, invasiveness and their ability to form colonies in soft agar. Bioinformatics and 3’UTR luciferase analyses identified E-cadherin (CDH1) and peroxisome proliferator-activated receptor alpha (PPARA) as direct downstream effectors of miR-9 activity. Inhibition of PPARA suppressed CDH1 mRNA levels, suggesting that miR-9 regulates CDH1 expression directly through binding in its 3’UTR and indirectly through PPARA. On the other hand, miR-9 inhibition of overexpression suppressed HCC tumorigenicity and invasiveness. PPARA and CDH1 mRNA levels were decreased in HCC relative to controls and were inversely correlated with miR-9 levels. Conclusions: Taken together, this study revealed the involvement of the miR-9/PPARA/CDH1 signaling pathway in HCC oncogenesis

Gauge theories and non-commutative geometry

It is shown that a $d$-dimensional classical SU(N) Yang-Mills theory can be formulated in a $d+2$-dimensional space, with the extra two dimensions forming a surface with non-commutative geometry. In this paper we present an explicit proof for the case of the torus and the sphere.Comment: 12 page

Covering Problems for Partial Words and for Indeterminate Strings

We consider the problem of computing a shortest solid cover of an indeterminate string. An indeterminate string may contain non-solid symbols, each of which specifies a subset of the alphabet that could be present at the corresponding position. We also consider covering partial words, which are a special case of indeterminate strings where each non-solid symbol is a don't care symbol. We prove that indeterminate string covering problem and partial word covering problem are NP-complete for binary alphabet and show that both problems are fixed-parameter tractable with respect to $k$, the number of non-solid symbols. For the indeterminate string covering problem we obtain a $2^{O(k \log k)} + n k^{O(1)}$-time algorithm. For the partial word covering problem we obtain a $2^{O(\sqrt{k}\log k)} + nk^{O(1)}$-time algorithm. We prove that, unless the Exponential Time Hypothesis is false, no $2^{o(\sqrt{k})} n^{O(1)}$-time solution exists for either problem, which shows that our algorithm for this case is close to optimal. We also present an algorithm for both problems which is feasible in practice.Comment: full version (simplified and corrected); preliminary version appeared at ISAAC 2014; 14 pages, 4 figure

Foucault's critical psychiatry and the spirit of the Enlightenment: a historico-philosophical study of psychiatry and its limits

My thesis revolves around three axes: the Foucauldian critical-historical method, its relationship with enlightenment critique and the way this critique is implemented in Foucault’s seminal work, History of Madness. Foucault’s exploration of the origins of psychiatry applies his own theories of power, truth and reason and draws on Kant’s philosophy, shedding new light on the way we perceive the birth and development of psychiatric practice. Following Foucault’s adoption of ‘limit attitude’, which investigates the limits of our thinking as points of disruption and renewal of established frames of reference, the thesis aims to dispel the widely accepted belief that psychiatry represents the triumph of rationalism by somehow conquering madness and turning it into an object of neutral, scientific perception. A history of limits examines the birth of psychiatry in its full complexity: in the late eighteenth century, doctors were not simply rationalists but also alienists, philosophers of finitude who recognized madness as an experience at the limits of reason, introducing a discourse which conditioned the formation of psychiatry as a type of medical activity. Since that event, the same type of recognition, the same anthropological confrontation with madness has persisted beneath the calm development of psychiatric rationality, undermining the supposed linearity, absolute authority and steady progress of psychiatric positivism. Foucault’s critique foregrounds this anthropological problematic as indispensable for psychiatry, encouraging psychiatrists to become aware of the epistemological limitations of their practice, and also to review the ethical and political issues which madness introduces into the apparent neutrality of current psychiatric discourse

Efficient Seeds Computation Revisited

The notion of the cover is a generalization of a period of a string, and there are linear time algorithms for finding the shortest cover. The seed is a more complicated generalization of periodicity, it is a cover of a superstring of a given string, and the shortest seed problem is of much higher algorithmic difficulty. The problem is not well understood, no linear time algorithm is known. In the paper we give linear time algorithms for some of its versions --- computing shortest left-seed array, longest left-seed array and checking for seeds of a given length. The algorithm for the last problem is used to compute the seed array of a string (i.e., the shortest seeds for all the prefixes of the string) in $O(n^2)$ time. We describe also a simpler alternative algorithm computing efficiently the shortest seeds. As a by-product we obtain an $O(n\log{(n/m)})$ time algorithm checking if the shortest seed has length at least $m$ and finding the corresponding seed. We also correct some important details missing in the previously known shortest-seed algorithm (Iliopoulos et al., 1996).Comment: 14 pages, accepted to CPM 201