REGIONAL COTTON ACREAGE RESPONSE

An econometric model of cotton acreage response was estimated for four distinct production regions in the United States. This work builds on previous work in the area of supply response under government farm programs and provides up-to-date regionalized estimates of own-price elasticity of cotton acreage supply. The own-price variable used in this study is a weighted combination of expected market price and government policy variables. Results indicate regional similarity in response to own price but differences with respect to the prices of alternative enterprises. Differences in regional response to paid diversion are also indicated.Crop Production/Industries,

Community Structure in Time-Dependent, Multiscale, and Multiplex Networks

Network science is an interdisciplinary endeavor, with methods and applications drawn from across the natural, social, and information sciences. A prominent problem in network science is the algorithmic detection of tightly-connected groups of nodes known as communities. We developed a generalized framework of network quality functions that allowed us to study the community structure of arbitrary multislice networks, which are combinations of individual networks coupled through links that connect each node in one network slice to itself in other slices. This framework allows one to study community structure in a very general setting encompassing networks that evolve over time, have multiple types of links (multiplexity), and have multiple scales.Comment: 31 pages, 3 figures, 1 table. Includes main text and supporting material. This is the accepted version of the manuscript (the definitive version appeared in Science), with typographical corrections included her

Organizational Design for Spill Containment in Deepwater Drilling Operations in the Gulf of Mexico: Assessment of the Marine Well Containment Company (MWCC)

The Deepwater Horizon oil spill in the Gulf of Mexico in April 2010 led to the deaths of 11 workers, a six-month moratorium on deepwater drilling in the Gulf, and nearly three months of massive engineering and logistics efforts to stop the spill. The series of failures before the well was finally capped and the spill contained revealed an inability to deal effectively with a well in deepwater and ultradeepwater. Ensuring that containment capabilities are adequate for drilling operations at these depths is therefore a salient challenge for government and industry. In this paper we assess the Marine Well Containment Company (MWCC), a consortium aimed at designing and building a system capable of containing future deepwater spills in the Gulf. We also consider alternatives for long-term readiness for deepwater spill containment. We focus on the roles of liability and regulation as determinants of readiness and the adequacy of incentives for technological innovation in oil spill containment technology to keep pace with advances in deepwater drilling capability. Liability and regulation can significantly influence the strength of these incentives. In addition, we discuss appropriate governance structure as a major determinant of the effectiveness of MWCC.oil spill, containment, industry R&D, liability, regulation, governance, innovation

MicroRNA-184 - An Ally in Calcium Signalling in the Skin

The skin provides a protective barrier against environmental, mechanical and microbial assault throughout life. Extracellular calcium (Ca2+) regulates the behavior of keratinocytes, the cells that form the epidermal layer of the skin. Calcium-dependent keratinocyte differentiation has been linked to microRNAs (miRNAs), small non-coding RNA molecules that attenuate gene output through mechanisms that culminate in target mRNA degradation. However, the impact of store-operated calcium entry (SOCE) on keratinocyte miRNA expression has received little attention. Here, I present our recent findings showing a relationship between SOCE and the induction of miRNA-184 (miR-184) in keratinocyte differentiation and migration. Levels of miR-184, barely detectable in untreated cells, rose by about 30-fold after keratinocytes were exposure to 1.5 mM Ca2+ for 5 days. Pharmacologic and genetic inhibitors of SOCE abrogated Ca2+-dependent miR-184 induction by 70%. Further, modulation of miR-184 levels using an exogenous miR-184 mimic or inhibitor enabled us to elucidate roles for miR-184 in keratinocyte differentiation. These include induction of involucrin, an important component of differentiating keratinocytes, elevation of p21 cyclin-dependent kinase (CDK) inhibitor and enhancement of DNA damage, as evidenced by higher levels of γH2AX, a marker of DNA double strand breaks. In addition, I will present our data implicating miR-184 in keratinocyte migration. We observed a 50-fold increase in miR-184 upon wounding keratinocyte monolayers. This occurred under routine low Ca2+ culture conditions, suggesting that high extracellular Ca2+is not an obligatory requirement for SOCE-dependent miR-184 induction. The induction of miR-184 in wounded monolayers was completely abolished in the presence of pharmacologic SOCE inhibitors. Transfection of keratinocytes with a miR-184 mimic stimulated migration in scratch assays, whereas the converse was observed when a miR-184 inhibitor was used. Together, these findings suggest miR-184 functions downstream of SOCE to promote differentiation and migration of epidermal keratinocytes

Movements and spawning of white marlin (Tetrapturus albidus) and blue marlin (Makaira nigricans) off Punta Cana, Dominican Republic

With a focus on white marlin (Tetrapturus albidus), a concurrent electronic tagging and larval sampling effort was conducted in the vicinity of Mona Passage (off southeast Hispaniola), Dominican Republic, during April and May 2003. Objectives were 1) to characterize the horizontal and vertical movement of adults captured from the area by using pop-up satellite archival tags (PSATs); and 2) by means of larval sampling, to investigate whether fish were reproducing. Trolling from a sportfishing vessel yielded eight adult white marlin and one blue marlin (Makaira nigricans); PSAT tags were deployed on all but one of these individuals. The exception was a female white marlin that was unsuitable for tagging because of injury; the reproductive state of its ovaries was examined histologically. Seven of the PSATs reported data summaries for water depth, temperature, and light levels measured every minute for periods ranging from 28 to 40 days. Displacement of marlin from the location of release to the point of tag pop-up ranged from 3l.6 to 267.7 nautical miles (nmi) and a mean displacement was 3.4 nmi per day for white marlin. White and blue marlin mean daily displacements appeared constrained compared to the results of other marlin PSAT tagging studies. White marlin ovarian sections contained postovulatory follicles and final maturation-stage oocytes, which indicated recent and imminent spawning. Neuston tows (n=23) yielded 18 istiophorid larvae: eight were white marlin, four were blue marlin, and six could not be identified to species. We speculate that the constrained movement patterns of adults may be linked to reproductive activity for both marlin species, and, if true, these movement patterns may have several implications for management. Protection of the potentially important white marlin spawning ground near Mona Passage seems warranted, at least until further studies can be conducted on the temporal and spatial extent of reproduction and associated adult movement

Myosin VIIA is required for aminoglycoside accumulation in cochlear hair cells.

Myosin VIIA is expressed by sensory hair cells and has a primary structure predicting a role in membrane trafficking and turnover, processes that may underlie the susceptibility of hair cells to aminoglycoside antibiotics. [3H]Gentamicin accumulation and the effects of aminoglycosides were therefore examined in cochlear cultures of mice with different missense mutations in the myosin VIIA gene, Myo7a, to see whether myosin VIIA plays a role in aminoglycoside ototoxicity. Hair cells from homozygous mutant Myo7a(sh1) mice, with a mutation in a non-conserved region of the myosin VIIA head, respond rapidly to aminoglycoside treatment and accumulate high levels of gentamicin. Hair cells from homozygous mutant Myo7a(6J) mice, with a mutation at a highly conserved residue close to the ATP binding site of the myosin VIIA head, do not accumulate [3H]gentamicin and are protected from aminoglycoside ototoxicity. Hair cells from heterozygotes of both alleles accumulate [3H]gentamicin and respond to aminoglycosides. Although aminoglycoside uptake is thought to be via apical surface-associated endocytosis, coated pit numbers on the apical membrane of heterozygous and homozygous Myo7a(6J) hair cells are similar. Pulse-chase experiments with cationic ferritin confirm that the apical endocytotic pathway is functional in homozygous Myo7a(6J) hair cells. Transduction currents can be recorded from both heterozygous and homozygous Myo7a(6J) hair cells, suggesting it is unlikely that the drug enters via diffusion through the mechanotransducer channel. The results show that myosin VIIA is required for aminoglycoside accumulation in hair cells. Myosin VIIA may transport a putative aminoglycoside receptor to the hair cell surface, indirectly translocate it to sites of membrane retrieval, or retain it in the endocytotic pathway

Herwig++ 2.0 Release Note

A new release of the Monte Carlo program Herwig++ (version 2.0) is now available. This is the first version of the program which can be used for hadron-hadron physics and includes the full simulation of both initial- and final-state QCD radiation.Comment: Source code and additional information available at http://hepforge.cedar.ac.uk/herwig

Using Stories in Coach Education

The purpose of this paper is to illustrate how storied representations of research can be used as an effective pedagogical tool in coach education. During a series of continuing professional development seminars for professional golf coaches, we presented our research in the form of stories and poems which were created in an effort to evoke and communicate the lived experiences of elite professional golfers. Following these presentations, we obtained written responses to the stories from 53 experienced coaches who attended the seminars. Analysis of this data revealed three ways in which coaches responded to the stories: (i) questioning; (ii) summarising; and (iii) incorporating. We conclude that these responses illustrate the potential of storied forms of representation to enhance professional development through stimulating reflective practice and increasing understanding of holistic, person-centred approaches to coaching athletes in high-performance sport