Evaluation of the capture efficiency and size selectivity of four pot types in the prospective fishery for North Pacific giant octopus (Enteroctopus dofleini)

Over 230 metric tons of octopus is harvested as bycatch annually in Alaskan trawl, long-line, and pot fisheries. An expanding market has fostered interest in the development of a directed fishery for North Pacific giant octopus (Enteroctopus dofleini). To investigate the potential for fishery development we examined the efficacy of four different pot types for capture of this species. During two surveys in Kachemak Bay, Alaska, strings of 16 –20 sablefish, Korean hair crab, shrimp, and Kodiak wooden lair pots were set at depths ranging between 62 and 390 meters. Catch per-unit-of-ef for t estimates were highest for sablefish and lair pots. Sablefish pots caught significantly heavier North Pacific giant octopuses but also produced the highest bycatch of commercially important species, such as halibut (Hippoglossus stenolepis), Pacific cod (Gadus macrocephalus), and Tanner crab (Chionoecetes bairdi)

Fermat, Leibniz, Euler, and the gang: The true history of the concepts of limit and shadow

Fermat, Leibniz, Euler, and Cauchy all used one or another form of approximate equality, or the idea of discarding "negligible" terms, so as to obtain a correct analytic answer. Their inferential moves find suitable proxies in the context of modern theories of infinitesimals, and specifically the concept of shadow. We give an application to decreasing rearrangements of real functions.Comment: 35 pages, 2 figures, to appear in Notices of the American Mathematical Society 61 (2014), no.

Using computer algorithms to elucidate zebra finch reproductive behaviour

Birds that experience variation in climatic conditions must maintain a stable nest temperature during incubation for successful hatching of offspring. Varying nest structure and incubation behaviour may be the methods birds use to regulate nest temperature. We used a modeling approach to investigate how birds adjust incubation behaviour to ambient temperature. Hidden Markov Models (HMM) have been used previously to predict the spatial distribution of animals based on the models’ ability to classify movement behaviour. We used a HMM to predict zebra finch (Taeniopygia guttata) incubation behaviour and nest structure from a nest temperature data set. The full data set consisted of data logger nest temperature records and video recordings of incubation behaviour in two different temperature conditions. Nest temperature from data loggers was used to obtain predictions about the timing, duration and frequency of incubation which could then be compared to video recordings of incubation behaviour and the structure of nests. Predicted results would be that zebra finches in a colder temperature would incubate for longer periods of time than warmer temperatures, and that experience at those temperatures would play a role in how successful their breeding attempt will be. This research explores new uses of computational techniques in animal behaviour, animal cognition, and behavioural ecology, provides new information about behavioural regulation of nest temperature during incubation, and develops practical techniques for inferring behaviour from data loggers in the field and in the lab

Neuronal pentraxins mediate synaptic refinement in the developing visual system

Peer reviewedPublisher PD

Investigating the biological properties of carbohydrate derived fulvic acid (CHD-FA) as a potential novel therapy for the management of oral biofilm infections.

Background: A number of oral diseases, including periodontitis, derive from microbial biofilms and are associated with increased antimicrobial resistance. Despite the widespread use of mouthwashes being used as adjunctive measures to control these biofilms, their prolonged use is not recommended due to various side effects. Therefore, alternative broad-spectrum antimicrobials that minimise these effects are highly sought after. Carbohydrate derived fulvic acid (CHD-FA) is an organic acid which has previously demonstrated to be microbiocidal against Candida albicans biofilms, therefore, the aims of this study were to evaluate the antibacterial activity of CHD-FA against orally derived biofilms and to investigate adjunctive biological effects.<p></p> Methods: Minimum inhibitory concentrations were evaluated for CHD-FA and chlorhexidine (CHX) against a range of oral bacteria using standardised microdilution testing for planktonic and sessile. Scanning electron microscopy was also employed to visualise changes in oral biofilms after antimicrobial treatment. Cytotoxicity of these compounds was assessed against oral epithelial cells, and the effect of CHD-FA on host inflammatory markers was assessed by measuring mRNA and protein expression.<p></p> Results: CHD-FA was highly active against all of the oral bacteria tested, including Porphyromonas gingivalis, with a sessile minimum inhibitory concentration of 0.5%. This concentration was shown to kill multi-species biofilms by approximately 90%, levels comparable to that of chlorhexidine (CHX). In a mammalian cell culture model, pretreatment of epithelial cells with buffered CHD-FA was shown to significantly down-regulate key inflammatory mediators, including interleukin-8 (IL-8), after stimulation with a multi-species biofilm.<p></p> Conclusions: Overall, CHD-FA was shown to possess broad-spectrum antibacterial activity, with a supplementary function of being able to down-regulate inflammation. These properties offer an attractive spectrum of function from a naturally derived compound, which could be used as an alternative topical treatment strategy for oral biofilm diseases. Further studies in vitro and in vivo are required to determine the precise mechanism by which CHD-FA modulates the host immune response.<p></p&gt

Dana Cole, Georgia Division of Public Health, Notifiable Disease Section, Department of Human Resources, 2 Peachtree Free-living Canada Geese and Antimicrobial Resistance

We describe antimicrobial resistance among Escherichia coli isolated from free-living Canada Geese in Georgia and North Carolina (USA). Resistance patterns are compared to those reported by the National Antimicrobial Resistance Monitoring System. Canada Geese may be vectors of antimicrobial resistance and resistance genes in agricultural environments

The first example of a paraben-dependent antibody to an Rh protein

Parabens are added to a commercial LISS (C-LISS) to retard microbial growth. Paraben-dependent anti-Jk a has been detected by the use of C-LISS. CASE REPORT: Serum from a D+ woman reacted in antiglobulin tests with RBCs stored (2-4 hours, 22-25 C) in C-LISS (L w and Messeter formulation, Immucor). Freshly prepared C-LISS-suspended RBCs did not react; nor did RBCs stored in LISS-additive reagents, PEG, saline, or homemade LISS. RESULTS: Studies using C-LISS-stored RBCs revealed an antibody that reacted with D+ and rrV+ RBCs, but not with r r, r r, or rrV-VS- RBCs. All partial D RBC phenotypes tested reacted, as did D+LW-, r G r, r G r, r y r, r s rV+VS+, and r s rV-VS+ RBCs. The active ingredient in C-LISS was propylparaben. Other LISS ingredients were not required; saline solutions of propylparaben, ethylparaben, methyl salicylate, 2-phenoxyethanol, and butylparaben were active. Methylparaben and methyl- m -hydroxybenzoate were inactive. Reactivity to C-LISS-stored RBCs could not be inhibited by propylparaben. Reactivity with D+V- and D-V+VS+ RBCs was not separable by adsorption-elution. CONCLUSIONS: This antibody likely detects a neoantigen formed between active compounds and RBC membranes. Review of the structure of active compounds suggests that proximity between methyl and hydroxyl groups is important for binding with RBC membranes. The role of RhD is unclear; no single portion of RhD protein appears to be implicated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73085/1/j.1537-2995.2001.41030371.x.pd

Leibniz's Infinitesimals: Their Fictionality, Their Modern Implementations, And Their Foes From Berkeley To Russell And Beyond

Many historians of the calculus deny significant continuity between infinitesimal calculus of the 17th century and 20th century developments such as Robinson's theory. Robinson's hyperreals, while providing a consistent theory of infinitesimals, require the resources of modern logic; thus many commentators are comfortable denying a historical continuity. A notable exception is Robinson himself, whose identification with the Leibnizian tradition inspired Lakatos, Laugwitz, and others to consider the history of the infinitesimal in a more favorable light. Inspite of his Leibnizian sympathies, Robinson regards Berkeley's criticisms of the infinitesimal calculus as aptly demonstrating the inconsistency of reasoning with historical infinitesimal magnitudes. We argue that Robinson, among others, overestimates the force of Berkeley's criticisms, by underestimating the mathematical and philosophical resources available to Leibniz. Leibniz's infinitesimals are fictions, not logical fictions, as Ishiguro proposed, but rather pure fictions, like imaginaries, which are not eliminable by some syncategorematic paraphrase. We argue that Leibniz's defense of infinitesimals is more firmly grounded than Berkeley's criticism thereof. We show, moreover, that Leibniz's system for differential calculus was free of logical fallacies. Our argument strengthens the conception of modern infinitesimals as a development of Leibniz's strategy of relating inassignable to assignable quantities by means of his transcendental law of homogeneity.Comment: 69 pages, 3 figure

Development of an in vitro periodontal biofilm model for assessing antimicrobial and host modulatory effects of bioactive molecules

Background: Inflammation within the oral cavity occurs due to dysregulation between microbial biofilms and the host response. Understanding how different oral hygiene products influence inflammatory properties is important for the development of new products. Therefore, creation of a robust host-pathogen biofilm platform capable of evaluating novel oral healthcare compounds is an attractive option. We therefore devised a multi-species biofilm co-culture model to evaluate the naturally derived polyphenol resveratrol (RSV) and gold standard chlorhexidine (CHX) with respect to anti-biofilm and anti-inflammatory properties.<p></p> Methods: An in vitro multi-species biofilm containing <i>S. mitis, F. nucleatum, P. Gingivalis</i> and <i>A. Actinomycetemcomitans</i> was created to represent a disease-associated biofilm and the oral epithelial cell in OKF6-TERT2. Cytotoxicity studies were performed using RSV and CHX. Multi-species biofilms were either treated with either molecule, or alternatively epithelial cells were treated with these prior to biofilm co-culture. Biofilm composition was evaluated and inflammatory responses quantified at a transcriptional and protein level.<p></p> Results: CHX was toxic to epithelial cells and multi-species biofilms at concentrations ranging from 0.01-0.2%. RSV did not effect multi-species biofilm composition, but was toxic to epithelial cells at concentrations greater than 0.01%. In co-culture, CHX-treated biofilms resulted in down regulation of the inflammatory chemokine IL-8 at both mRNA and protein level. RSV-treated epithelial cells in co-culture were down-regulated in the release of IL-8 protein, but not mRNA.<p></p> Conclusions: CHX possesses potent bactericidal properties, which may impact downstream inflammatory mediators. RSV does not appear to have bactericidal properties against multi-species biofilms, however it did appear to supress epithelial cells from releasing inflammatory mediators. This study demonstrates the potential to understand the mechanisms by which different oral hygiene products may influence gingival inflammation, thereby validating the use of a biofilm co-culture model.<p></p&gt

Rapid screening of Salmonella enterica serovars Enteritidis, Hadar, Heidelberg and Typhimurium using a serologically-correlative allelotyping PCR targeting the O and H antigen alleles

<p>Abstract</p> <p>Background</p> <p>Classical <it>Salmonella </it>serotyping is an expensive and time consuming process that requires implementing a battery of O and H antisera to detect 2,541 different <it>Salmonella enterica </it>serovars. For these reasons, we developed a rapid multiplex polymerase chain reaction (PCR)-based typing scheme to screen for the prevalent <it>S. enterica </it>serovars Enteritidis, Hadar, Heidelberg, and Typhimurium.</p> <p>Results</p> <p>By analyzing the nucleotide sequences of the genes for O-antigen biosynthesis including <it>wb</it>a operon and the central variable regions of the H1 and H2 flagellin genes in <it>Salmonella</it>, designated PCR primers for four multiplex PCR reactions were used to detect and differentiate <it>Salmonella </it>serogroups A/D1, B, C1, C2, or E1; H1 antigen types i, g, m, r or z₁₀; and H2 antigen complexes, I: 1,2; 1,5; 1,6; 1,7 or II: e,n,x; e,n,z₁₅. Through the detection of these antigen gene allele combinations, we were able to distinguish among <it>S. enterica </it>serovars Enteritidis, Hadar, Heidelberg, and Typhimurium. The assays were useful in identifying <it>Salmonella </it>with O and H antigen gene alleles representing 43 distinct serovars. While the H2 multiplex could discriminate between unrelated H2 antigens, the PCR could not discern differences within the antigen complexes, 1,2; 1,5; 1,6; 1,7 or e,n,x; e,n,z₁₅, requiring a final confirmatory PCR test in the final serovar reporting of <it>S. enterica</it>.</p> <p>Conclusion</p> <p>Multiplex PCR assays for detecting specific O and H antigen gene alleles can be a rapid and cost-effective alternative approach to classical serotyping for presumptive identification of <it>S. enterica </it>serovars Enteritidis, Hadar, Heidelberg, and Typhimurium.</p