THE USE OF COST-TRANSFER ANALYSIS TO ESTIMATE THE ECONOMIC IMPACTS OF A POTENTIAL ZEBRA MUSSEL INFESTATION IN FLORIDA

Zebra mussel (Dreissena polymorpha) colonization of the eastern United States has resulted in expenditures of tens of millions of dollars spent by consumptive surface water users, in order to mitigate infrastructure impairment caused by this invasive species. Analogous to benefit-transfer analysis, a "cost-transfer" approach will be used to obtain general estimates of potential mitigation costs of zebra mussels in an area (Florida) that this invasive species has yet to establish itself. The goal of this research is to provide initial information about this issue to parties interested in, and/or charged with, invasive species management in the state of Florida.Bio-fouling, cost-transfer, economic impacts, Florida surface water users, monitoring and control, zebra mussels, Risk and Uncertainty,

Optimal investment in prevention and control of a potential invader: the case of zebra mussels in Florida waterways

The probability of a severe infestation ranges from 2% to 98% depending on investment in monitoring, prevention, and response technology. Given the estimated potential for economic damages, preliminary results indicate that prudent investment in prevention and early response net a present value net return of $10 million over 20 years.Invasive species, bio-pollutant, control cost, cost transfer, surface water, risk, Environmental Economics and Policy,

Analytical Gradients for Projection-Based Wavefunction-in-DFT Embedding

Projection-based embedding provides a simple, robust, and accurate approach for describing a small part of a chemical system at the level of a correlated wavefunction method while the remainder of the system is described at the level of density functional theory. Here, we present the derivation, implementation, and numerical demonstration of analytical nuclear gradients for projection-based wavefunction-in-density functional theory (WF-in-DFT) embedding. The gradients are formulated in the Lagrangian framework to enforce orthogonality, localization, and Brillouin constraints on the molecular orbitals. An important aspect of the gradient theory is that WF contributions to the total WF-in-DFT gradient can be simply evaluated using existing WF gradient implementations without modification. Another simplifying aspect is that Kohn-Sham (KS) DFT contributions to the projection-based embedding gradient do not require knowledge of the WF calculation beyond the relaxed WF density. Projection-based WF-in-DFT embedding gradients are thus easily generalized to any combination of WF and KS-DFT methods. We provide numerical demonstration of the method for several applications, including calculation of a minimum energy pathway for a hydride transfer in a cobalt-based molecular catalyst using the nudged-elastic-band method at the CCSD-in-DFT level of theory, which reveals large differences from the transition state geometry predicted using DFT.Comment: 15 pages, 4 figure

An exploratory pilot study of mechanisms of action within normative feedback for adult drinkers

Background. Normative feedback (NF), or receiving information about one’s drinking compared to peer drinking norms, is one of the most widely used brief interventions for prevention and intervention for hazardous alcohol use. NF has demonstrated predominantly small but significant effect sizes for intention to change and other drinking related outcomes. Identifying mechanisms of action may improve the effectiveness of NF; however, few studies have examined NF’s mechanisms of action, particularly among adults. Objective. This study is an exploratory analysis of two theorized mechanisms of NF: discrepancy (specifically personal dissonance—the affective response to feedback) and belief in the accuracy of feedback. Method. Using Amazon’s Mechanical Turk, 87 men (n = 56) and women (n = 31) completed an online survey during which they were asked about their perceptions about their drinking and actual drinking behaviors. Then participants were provided tailored NF and evaluated for their reactions. Severity of discrepancy was measured by the difference between one’s estimated percentile ranking of drinking compared to peers and actual percentile ranking. Surprise and worry reported due to the discrepancy were proxies for personal dissonance. Participants were also asked if they believed the feedback and if they had any plans to change their drinking. Mediation analyses were implemented, exploring whether surprise, worry, or belief in the accuracy of feedback mediated severity of discrepancy’s impact on plan for change. Results. Among this sample of adult drinkers, severity of discrepancy did not predict plan for change, and personal dissonance did not mediate severity of discrepancy. Severity of discrepancy was mediated by belief in the accuracy of feedback. In addition, viewing one’s drinking as a problem prior to feedback and post-NF worry both predicted plan for change independently. Conclusions. Results revealed that NF may not work to create personal dissonance through discrepancy, but belief in the accuracy of feedback may be important. It appears the more one believes the feedback, the more one makes a plan for change, suggesting practitioners should be mindful of how information within feedback is presented. Findings also indicate NF may work by validating a preexisting perception that drinking is a problem instead of creating concern related to discrepancy where none existed. Limitations regarding generalizability are discussed

Highly Coordinated Gene Regulation in Mouse Skeletal Muscle Regeneration

Mammalian skeletal muscles are capable of regeneration after injury. Quiescent satellite cells are activated to reenter the cell cycle and to differentiate for repair, recapitulating features of myogenesis during embryonic development. To understand better the molecular mechanism involved in this process in vivo, we employed high density cDNA microarrays for gene expression profiling in mouse tibialis anterior muscles after a cardiotoxin injection. Among 16,267 gene elements surveyed, 3,532 elements showed at least a 2.5-fold change at one or more time points during a 14-day time course. Hierarchical cluster analysis and semiquantitative reverse transcription-PCR showed induction of genes important for cell cycle control and DNA replication during the early phase of muscle regeneration. Subsequently, genes for myogenic regulatory factors, a group of imprinted genes and genes with functions to inhibit cell cycle progression and promote myogenic differentiation, were induced when myogenic stem cells started to differentiate. Induction of a majority of these genes, including E2f1 and E2f2, was abolished in muscles lacking satellite cell activity after gamma radiation. Regeneration was severely compromised in E2f1 null mice but not affected in E2f2 null mice. This study identifies novel genes potentially important for muscle regeneration and reveals highly coordinated myogenic cell proliferation and differentiation programs in adult skeletal muscle regeneration in vivo

Episodic fevers and vasodilatory shock mimicking urosepsis in a patient with HIV-associated multicentric Castleman’s Disease: a case report

Background: Multicentric Castleman's disease (MCD) is a pre-malignancy that presents with lymphadenopathy and features of systemic inflammation. Human immunodeficiency virus (HIV)-associated MCD is associated with human herpesvirus-8 (HHV-8) infection. If untreated MCD has a relapsing and remitting course that is eventually fatal. Case presentation: A 67-year-old man had six hospital admissions over 20 months characterised by fever, urinary frequency and CRP >100 mg/L. The final admission was complicated by hypotension requiring intensive care unit admission and ionotropic support. His history included HIV and Hepatitis B virus (HBV) co-infection on suppressive therapy. Each presentation was managed as presumed urosepsis with use of empirical antibiotics, however numerous blood and urine cultures failed to identify a pathogen. A bone-marrow aspirate and trephine found no evidence of haematological malignancy. A positron emission tomography scan found active lymph nodes, one of which was biopsied and found to contain the plasma-cell variant of Castleman's disease. Ultimately the cause for the recurrent presentations was attributed to progressive MCD. The patient received rituximab monotherapy and has had no further related admissions. Conclusions: MCD should be considered in patients with chronic HIV infection presenting with recurrent sepsis-like episodes and/or vasodilatory shock, particularly if no pathogen is identified or lymphadenopathy is evident

G9a regulates temporal preimplantation developmental program and lineage segregation in blastocyst

Early mouse development is regulated and accompanied by dynamic changes in chromatin modifications, including G9a-mediated histone H3 lysine 9 dimethylation (H3K9me2). Previously, we provided insights into its role in post-implantation development (Zylicz et al., 2015). Here we explore the impact of depleting the maternally inherited G9a in oocytes on development shortly after fertilisation. We show that G9a accumulates typically at 4 to 8-cell stage to promote timely repression of a subset of 4-cell stage-specific genes. Loss of maternal inheritance of G9a disrupts the gene regulatory network resulting in developmental delay and destabilisation of inner cell mass lineages by the late blastocyst stage. Our results indicate a vital role of this maternally inherited epigenetic regulator in creating conducive conditions for developmental progression and on cell fate choices.Wellcome Trust/CRUK Gurdon Institute, University of Cambridge Wellcome Trust/Medical Research Council, Stem Cell Institute, University of Cambridg

Identification of Pseudomonas aeruginosa Phenazines that Kill Caenorhabditis elegans

Pathogenic microbes employ a variety of methods to overcome host defenses, including the production and dispersal of molecules that are toxic to their hosts. Pseudomonas aeruginosa, a Gram-negative bacterium, is a pathogen of a diverse variety of hosts including mammals and the nematode Caenorhabditis elegans. In this study, we identify three small molecules in the phenazine class that are produced by P. aeruginosa strain PA14 that are toxic to C. elegans. We demonstrate that 1-hydroxyphenazine, phenazine-1-carboxylic acid, and pyocyanin are capable of killing nematodes in a matter of hours. 1-hydroxyphenazine is toxic over a wide pH range, whereas the toxicities of phenazine-1-carboxylic acid and pyocyanin are pH-dependent at non-overlapping pH ranges. We found that acidification of the growth medium by PA14 activates the toxicity of phenazine-1-carboxylic acid, which is the primary toxic agent towards C. elegans in our assay. Pyocyanin is not toxic under acidic conditions and 1-hydroxyphenazine is produced at concentrations too low to kill C. elegans. These results suggest a role for phenazine-1-carboxylic acid in mammalian pathogenesis because PA14 mutants deficient in phenazine production have been shown to be defective in pathogenesis in mice. More generally, these data demonstrate how diversity within a class of metabolites could affect bacterial toxicity in different environmental niches.Chemistry and Chemical Biolog