Southern Illinois University is a public research university located in Carbondale, Illinois, United States. Founded in 1869, SIU is the flagship campus of the Southern Illinois University system. The university is known as SIU Carbondale, but colloquially as SIU. SIU's total student enrollment is almost 18,000.The University is categorized as an RU/H Research University in the Carnegie Classification of Institutions of Higher Education. SIU is recognized in the U.S. News & World Report rankings as a "National University," that is, a university which grants a variety of doctoral degrees and strongly emphasizes research; SIU's ranking in the 2011 US News ratings is #170. Additionally, the National Science Foundation ranks SIU #101 among public universities in the U.S. for total research and development expenditures, and #142 among all U.S. universities. The University offers more than 200 undergraduate majors, minors, and specializations, 30 doctoral and more than 60 master's degree programs; law and medical degrees. Wikipedia.
MacLean 2nd. J.A.,Southern Illinois University Carbondale
Biology of reproduction | Year: 2012
The mechanisms by which the region-specific expression patterns of clustered genes evolve are poorly understood. The epididymis is an ideal organ to examine this, as it is a highly segmented tissue that differs significantly in structure between closely related species. Here we examined this issue through analysis of the rapidly evolving X-linked reproductive homeobox (Rhox) gene cluster, the largest known homeobox gene cluster in metazoans. In the mouse, we found that most Rhox genes are expressed primarily in the caput region of the epididymis, a site where sperm mature and begin acquiring forward motility. This region-specific expression pattern depends, in part, on the founding member of the Rhox cluster--Rhox5--as targeted mutation of Rhox5 greatly diminishes the expression of several other family members in the caput region. In the rat, Rhox5 expression switches from the caput to the site of sperm storage: the cauda. All Rhox genes under the control of Rhox5 in the mouse epididymis display a concomitant change in their regional expression in the rat epididymis. Our results lead us to propose that widespread changes in the region-specific expression pattern of genes over evolutionary time can be the result of alterations of one or only a few master regulatory genes.
Silbert L.E.,Southern Illinois University Carbondale
Soft Matter | Year: 2010
The role of the friction coefficient, μ, on the jamming properties of disordered, particle packings is studied using computer simulations. Compressed, soft-sphere packings are brought towards the jamming transition - the point where a packing loses mechanical stability - by decreasing the packing fraction. The values of the packing fraction at the jamming transition, μ c, gradually decrease from the random close packing point for zero friction, to a value coincident with random loose packing as the friction coefficient is increased over several orders of magnitude. This is accompanied by a decrease in the coordination number at the jamming transition, zμ c, which varies from approximately six to four with increasing friction. Universal power law scaling is observed in the pressure and coordination number as a function of distance from the generalised, friction-dependent jamming point. Various power laws are also reported between the μ c, zμ c, and μ. Dependence on preparation history of the packings is also investigated. © 2010 The Royal Society of Chemistry.
Lydy M.J.,Southern Illinois University Carbondale
Integrated environmental assessment and management | Year: 2014
This manuscript surveys the literature on passive sampler methods (PSMs) used in contaminated sediments to assess the chemical activity of organic contaminants. The chemical activity in turn dictates the reactivity and bioavailability of contaminants in sediment. Approaches to measure specific binding of compounds to sediment components, for example, amorphous carbon or specific types of reduced carbon, and the associated partition coefficients are difficult to determine, particularly for native sediment. Thus, the development of PSMs that represent the chemical activity of complex compound-sediment interactions, expressed as the freely dissolved contaminant concentration in porewater (Cfree ), offer a better proxy for endpoints of concern, such as reactivity, bioaccumulation, and toxicity. Passive sampling methods have estimated Cfree using both kinetic and equilibrium operating modes and used various polymers as the sorbing phase, for example, polydimethylsiloxane, polyethylene, and polyoxymethylene in various configurations, such as sheets, coated fibers, or vials containing thin films. These PSMs have been applied in laboratory exposures and field deployments covering a variety of spatial and temporal scales. A wide range of calibration conditions exist in the literature to estimate Cfree , but consensus values have not been established. The most critical criteria are the partition coefficient between water and the polymer phase and the equilibrium status of the sampler. In addition, the PSM must not appreciably deplete Cfree in the porewater. Some of the future challenges include establishing a standard approach for PSM measurements, correcting for nonequilibrium conditions, establishing guidance for selection and implementation of PSMs, and translating and applying data collected by PSMs. © 2014 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of SETAC.
Kochel T.R.,Southern Illinois University Carbondale
Justice Quarterly | Year: 2012
This research empirically examines the role of police in promoting collective efficacy and in particular, whether higher levels of police legitimacy are associated with more neighborhood collective efficacy. The research is conducted in the developing nation of Trinidad and Tobago-providing important evidence about the generalizability of the antecedents and effects of legitimacy outside of industrialized nations. The results support a potential role for police in promoting collective efficacy, but the mechanism for doing so is not legal institution legitimacy. Instead, the research identifies a relationship between quality routine police services, levels of police misconduct, and collective efficacy. In Trinidad, the amount and nature of interactions with police appear to play an important part in residents' and neighborhood-level assessments about police services and misbehavior. © 2012 Copyright Academy of Criminal Justice Sciences.
Bhaumik S.R.,Southern Illinois University Carbondale
Biochimica et Biophysica Acta - Gene Regulatory Mechanisms | Year: 2011
A growing number of human diseases are linked to abnormal gene expression which is largely controlled at the level of transcriptional initiation. The gene-specific activator promotes the initiation of transcription through its interaction with one or more components of the transcriptional initiation machinery, hence leading to stimulated transcriptional initiation or activation. However, all activator proteins do not target the same component(s) of the transcriptional initiation machinery. Rather, they can have different target specificities, and thus, can lead to distinct mechanisms of transcriptional activation. Two such distinct mechanisms of transcriptional activation in yeast are mediated by the SAGA (Spt-Ada-Gcn5-Acetyltransferase) and TFIID (Transcription factor IID) complexes, and are termed as "SAGA-dependent" and "TFIID-dependent" transcriptional activation, respectively. SAGA is the target of the activator in case of SAGA-dependent transcriptional activation, while the targeting of TFIID by the activator leads to TFIID-dependent transcriptional activation. Both the SAGA and TFIID complexes are highly conserved from yeast to human, and play crucial roles in gene activation among eukaryotes. The regulatory mechanisms of eukaryotic transcriptional activation by SAGA and TFIID are discussed here. © 2010 Elsevier B.V.