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Full-Text Articles in Physical Sciences and Mathematics

Can Acute Dermal Systemic Toxicity Tests Be Replaced With Oral Tests? A Comparison Of Route-Specific Systemic Toxicity And Hazard Classifications Under The Globally Harmonized System Of Classification And Labelling Of Chemicals (Ghs), Nigel P. Moore, David J. Andrew, Donald L. Bjerke, Stuart Creton, David Dreher, Thomas Holmes, Pilar Prieto, Troy Seidle, Tim G. Rowan Dec 2014

Can Acute Dermal Systemic Toxicity Tests Be Replaced With Oral Tests? A Comparison Of Route-Specific Systemic Toxicity And Hazard Classifications Under The Globally Harmonized System Of Classification And Labelling Of Chemicals (Ghs), Nigel P. Moore, David J. Andrew, Donald L. Bjerke, Stuart Creton, David Dreher, Thomas Holmes, Pilar Prieto, Troy Seidle, Tim G. Rowan

Troy Seidle, PhD

Acute systemic toxicity data (LD50 values) and hazard classifications derived in the rat following oral administration and dermal application have been analysed to examine whether or not orally-derived hazard classification or LD50 values can be used to determine dermal hazard classification. Comparing the oral and dermal classifications for 335 substances derived from oral and dermal LD50 values respectively revealed 17% concordance, and indicated that 7% of substances would be classified less severely while 76% would be classified more severely if oral classifications were applied directly to the dermal route. In contrast, applying the oral LD50 values within the dermal classification …


An Evaluation Of The Us High Production Volume (Hpv) Chemical-Testing Programme: A Study In (Ir)Relevance, Redundancy And Retro Thinking, Andrew Nicholson, Jessica Sandler, Troy Seidle Dec 2014

An Evaluation Of The Us High Production Volume (Hpv) Chemical-Testing Programme: A Study In (Ir)Relevance, Redundancy And Retro Thinking, Andrew Nicholson, Jessica Sandler, Troy Seidle

Troy Seidle, PhD

Under the US Environmental Protection Agency (EPA) High Production Volume (HPV) Challenge Programme, chemical companies have volunteered to conduct screening-level toxicity tests on approximately 2800 widely-used industrial chemicals. Participating companies are committed to providing available toxicity information to the EPA and presenting testing proposals for review by the EPA and posting on the EPA Web site as public information. People for the Ethical Treatment of Animals (PETA) and a coalition of animal protection organisations have reviewed all the test plans submitted by the participating chemical companies for compliance with the original HPV framework, as well as with animal welfare guidelines …


The Development Of New Concepts For Assessing Reproductive Toxicity Applicable To Large Scale Toxicological Programmes, S. Bremer, C. Pellizzer, S. Hoffmann, T. Seidle, T. Hartung Dec 2014

The Development Of New Concepts For Assessing Reproductive Toxicity Applicable To Large Scale Toxicological Programmes, S. Bremer, C. Pellizzer, S. Hoffmann, T. Seidle, T. Hartung

Troy Seidle, PhD

Large scale toxicological testing programmes which are currently ongoing such as the new European chemical legislation REACH require the development of new integrated testing strategies rather than applying traditional testing schemes to thousands of chemicals. The current practice of requiring in vivo testing for every possible adverse effect endanger the success of these programmes due (i) to limited testing facilities and sufficient capacity of scientific/technical knowledge for reproductive toxicity; (ii) an unacceptable number of laboratory animals involved (iii) an intolerable number of chemicals classified as false positive.

A key aspect of the implementation of new testing strategies is the determination …


A Modular One-Generation Reproduction Study As A Flexible Testing System For Regulatory Safety Assessment, Richard Vogel, Troy Seidle, Horst Spielmann Dec 2014

A Modular One-Generation Reproduction Study As A Flexible Testing System For Regulatory Safety Assessment, Richard Vogel, Troy Seidle, Horst Spielmann

Troy Seidle, PhD

The European Union’s Registration, Evaluation and Authorisation of Chemicals (REACH) legislation mandates testing and evaluation of approximately 30,000 existing substances within a short period of time, beginning with the most widely used “high production volume” (HPV) chemicals. REACH testing requirements for the roughly 3000 HPV chemicals specify three separate tests for reproductive toxicity: two developmental toxicity studies on different animal species (OECD Test Guideline 414) and a two-generation reproduction toxicity study (OECD TG 416). These studies are highly costly in both economic and animal welfare terms. OECD TG 416 is a fertility study intended to evaluate reproductive performance of animals …


The Fine-Scale Habitat Use Of Risso’S Dolphins Off Bardsey Island, Cardigan Bay (Uk), Marijke N. De Boer, Sonja Eisfeld, Mark P. Simmonds Dec 2014

The Fine-Scale Habitat Use Of Risso’S Dolphins Off Bardsey Island, Cardigan Bay (Uk), Marijke N. De Boer, Sonja Eisfeld, Mark P. Simmonds

Mark P. Simmonds, OBE

The main objectives of this study were (1) to estimate the population size of Risso’s dolphins off Bardsey Island using mark-recapture techniques (De Boer et al., 2013); and (2) to study habitat-use in relation to fine-scale oceanographic features. This work provides preliminary information on the habitat-use of Risso’s dolphins and will benefit future studies, along with the development of effective conservation measures for this species throughout the region.


Cetaceans And Marine Debris: The Great Unknown, Mark Peter Simmonds Dec 2014

Cetaceans And Marine Debris: The Great Unknown, Mark Peter Simmonds

Mark P. Simmonds, OBE

Plastics and other marine debris have been found in the gastrointestinal tracts of cetaceans, including instances where large quantities of material have been found that are likely to cause impairment to digestive processes and other examples, where other morbidity and even death have resulted. In some instances, debris may have been ingested as a result of the stranding process and, in others, it may have been ingested when feeding. Those species that are suction or “ram” feeders may be most at risk. There is also evidence of entanglement of cetaceans in marine debris. However, it is usually difficult to distinguish …


Interactions Between Short-Beaked Common Dolphin (Delphinus Delphis) And The Winter Pelagic Pair-Trawl Fishery Ff Southwest England (Uk), Marijke N. De Boer, James T. Saulino, Mardik F. Leopold, Peter J.H. Reijnders, Mark P. Simmonds Dec 2014

Interactions Between Short-Beaked Common Dolphin (Delphinus Delphis) And The Winter Pelagic Pair-Trawl Fishery Ff Southwest England (Uk), Marijke N. De Boer, James T. Saulino, Mardik F. Leopold, Peter J.H. Reijnders, Mark P. Simmonds

Mark P. Simmonds, OBE

During offshore and onshore studies (2004 to 2009), the interactions between pair-trawls and short-beaked common dolphins (Delphinus delphis) were studied to better understand the impact of bycatch. A ‘hotspot’ area where pair-trawls overlapped with high dolphin abundance was identified. We made comparisons between boat-based data collected in absence and presence of pair-trawlers. The relative abundance and group-size of dolphins was significantly higher in the presence of pair-trawlers. Dolphins were observed associating with towing and hauling procedures. Significantly, more carcasses occurred in areas with hauling-activity than those without. Body-temperatures obtained from carcasses found near operating pair-trawlers indicated that bycatch mostly occurred …


Health Professionals’ Roles In Animal Agriculture, Climate Change, And Human Health, Aysha Z. Akhtar, Michael Greger, Hope Ferdowsian, Erica Frank Dec 2014

Health Professionals’ Roles In Animal Agriculture, Climate Change, And Human Health, Aysha Z. Akhtar, Michael Greger, Hope Ferdowsian, Erica Frank

Michael Greger, MD, FACLM

What we eat is rapidly becoming an issue of global concern. With food shortages, the rise in chronic disease, and global warming, the impact of our dietary choices seems more relevant today than ever. Globally, a transition is taking place toward greater consumption of foods of animal origin, in lieu of plantbased diets. With this transition comes intensification of animal agriculture that in turn is associated with the emergence of zoonotic infectious diseases, environmental degradation, and the epidemics of chronic disease and obesity. Health professionals should be aware of these trends and consider them as they promote healthier and more …


Volunteer Studies In Pain Research — Opportunities And Challenges To Replace Animal Experiments: The Report And Recommendations Of A Focus On Alternatives Workshop, C. K. Langley, Q. Aziz, C. Bountra, N. Gordon, P. Hawkins, A. Jones, G. Langley, T. Nurmikko, I. Tracey Nov 2014

Volunteer Studies In Pain Research — Opportunities And Challenges To Replace Animal Experiments: The Report And Recommendations Of A Focus On Alternatives Workshop, C. K. Langley, Q. Aziz, C. Bountra, N. Gordon, P. Hawkins, A. Jones, G. Langley, T. Nurmikko, I. Tracey

Gill Langley, PhD

Despite considerable research, effective and safe treatments for human pain disorders remain elusive. Understanding the biology of different human pain conditions and researching effective treatments continue to be dominated by animal models, some of which are of limited value. British and European legislation demands that non-animal approaches should be considered before embarking on research using experimental animals. Recent scientific and technical developments, particularly in human neuroimaging, offer the potential to replace some animal procedures in the study of human pain. A group of pain research experts from academia and industry met with the aim of exploring creatively the tools, strategies …


The Validity Of Animal Experiments In Medical Research, Gill Langley Nov 2014

The Validity Of Animal Experiments In Medical Research, Gill Langley

Gill Langley, PhD

Other animals, such as mice, rats, rabbits, dogs and monkeys, are widely used as surrogates for humans in fundamental medical research. This involves creating disorders in animals by chemical, surgical or genetic means, with the aim of mimicking selected aspects of human illnesses. It is a truism that any model or surrogate is not identical to the target being modelled. So, in medical research, experiments using animals or cell cultures or even healthy volunteers instead of patients (being the target population with the target illness) will inevitably have limitations, although these will be greater or lesser depending on the model.


Conversion Of Red Fluorescent Protein Into A Bright Blue Probe, Oksana M. Subach, Illia S. Gundorov, Masami Yoshimura, Fedor V. Subach, Jinghang Zhang, David Grunwald, Ekaterina A. Souslova, Dmitriy M. Chudakov, Vladislav V. Verkhusha Nov 2014

Conversion Of Red Fluorescent Protein Into A Bright Blue Probe, Oksana M. Subach, Illia S. Gundorov, Masami Yoshimura, Fedor V. Subach, Jinghang Zhang, David Grunwald, Ekaterina A. Souslova, Dmitriy M. Chudakov, Vladislav V. Verkhusha

David Grünwald

We used a red chromophore formation pathway, in which the anionic red chromophore is formed from the neutral blue intermediate, to suggest a rational design strategy to develop blue fluorescent proteins with a tyrosine-based chromophore. The strategy was applied to red fluorescent proteins of the different genetic backgrounds, such as TagRFP, mCherry, HcRed1, M355NA, and mKeima, which all were converted into blue probes. Further improvement of the blue variant of TagRFP by random mutagenesis resulted in an enhanced monomeric protein, mTagBFP, characterized by the substantially higher brightness, the faster chromophore maturation, and the higher pH stability than blue fluorescent proteins …


Tal Effector-Nucleotide Targeter (Tale-Nt) 2.0: Tools For Tal Effector Design And Target Prediction, Erin L. Doyle, Nicholas J. Booher, Daniel S. Standage, Daniel F. Voytas, Volker P. Brendel, John K. Vandyk, Adam J. Bogdanove Oct 2014

Tal Effector-Nucleotide Targeter (Tale-Nt) 2.0: Tools For Tal Effector Design And Target Prediction, Erin L. Doyle, Nicholas J. Booher, Daniel S. Standage, Daniel F. Voytas, Volker P. Brendel, John K. Vandyk, Adam J. Bogdanove

John K. VanDyk

Transcription activator-like (TAL) effectors are repeat-containing proteins used by plant pathogenic bacteria to manipulate host gene expression. Repeats are polymorphic and individually specify single nucleotides in the DNA target, with some degeneracy. A TAL effector-nucleotide binding code that links repeat type to specified nucleotide enables prediction of genomic binding sites for TAL effectors and customization of TAL effectors for use in DNA targeting, in particular as custom transcription factors for engineered gene regulation and as site-specific nucleases for genome editing. We have developed a suite of web-based tools called TAL Effector-Nucleotide Targeter 2.0 (TALE-NT 2.0;https://boglab.plp.iastate.edu/) that enables design of custom …


The Ups And Downs Of Knowledge Infrastructures In Science: Implications For Data Management, Christine L. Borgman, Peter T. Darch, Ashley E. Sands, Jillian C. Wallis, Sharon Traweek Aug 2014

The Ups And Downs Of Knowledge Infrastructures In Science: Implications For Data Management, Christine L. Borgman, Peter T. Darch, Ashley E. Sands, Jillian C. Wallis, Sharon Traweek

Christine L. Borgman

The promise of technology-enabled, data-intensive scholarship is predicated upon access to knowledge infrastructures that are not yet in place. Scientific data management requires expertise in the scientific domain and in organizing and retrieving complex research objects. The Knowledge Infrastructures project compares data management activities of four large, distributed, multidisciplinary scientific endeavors as they ramp their activities up or down; two are big science and two are small science. Research questions address digital library solutions, knowledge infrastructure concerns, issues specific to individual domains, and common problems across domains. Findings are based on interviews (n=113 to date), ethnography, and other analyses of …


Heterogeneous Rotational Diffusion Of A Fluorescent Probe In Lipid Monolayers, Christina M. Othon Aug 2014

Heterogeneous Rotational Diffusion Of A Fluorescent Probe In Lipid Monolayers, Christina M. Othon

Christina M Othon

The rotational correlation time of the lipid probe 1-palmitoyl-2-{6-[(7-nitro-2-1,3-benzoxadiazol-4-yl)amino]hexanoyl}-sn-glycero-3-phosphocholine (NBD-PC) is measured using fluorescence anisotropy for two lipid species. We measure the rotational diffusion in a monolayer of 1,2-Didecanoyl-sn-glycero-3-phosphocholine (DPPC) which displays a phase transition at room temperature from the liquid expanded to the liquid-condensed phase. The constant rotational diffusion of the probe throughout the phase transition reflects the measurement of dynamics in only the liquid-expanded phase. We contrast the dynamic changes during this phase coexistence to the continuous density increase observed in 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) at room temperature. We observe a non-exponential decay of the probe diffusion consistent with heterogeneity …


Evidence Of Enso Mega-Drought Triggered Collapse Of Prehistory Aboriginal Society In Northwest Australia, Hamish Mcgowan, Samuel K. Marx, P Moss, Andrew Hammond Aug 2014

Evidence Of Enso Mega-Drought Triggered Collapse Of Prehistory Aboriginal Society In Northwest Australia, Hamish Mcgowan, Samuel K. Marx, P Moss, Andrew Hammond

Samuel K Marx

The Kimberley region of northwest Australia contains one of the World's largest collections of rock art characterised by two distinct art forms; the fine featured anthropomorphic figures of the Gwion Gwion or Bradshaw paintings, and broad stroke Wandjina figures. Luminescence dating of mud wasp nests overlying Gwion Gwion paintings has confirmed an age of at least 17,000 yrs B.P. with the most recent dates for these paintings from around the mid-Holocene (5000 to 7000 yrs B.P.). Radiocarbon dating indicates that the Wandjina rock art then emerged around 3800 to 4000 yrs B.P. following a hiatus of at least 1200 yrs. …


Dust Transport And Deposition In A Superhumid Environment, Samuel K. Marx, Hamish A. Mcgowan Aug 2014

Dust Transport And Deposition In A Superhumid Environment, Samuel K. Marx, Hamish A. Mcgowan

Samuel K Marx

Contemporary rates of dust deposition monitored along a 300-km section of the superhumid West Coast of New Zealand's South Island are presented. In this setting, dust is entrained primarily from the dry channels of braided glaciofluvial rivers that drain the western slopes of the Southern Alps. Measured dust deposition ranged between 0.21 and 118.9 kg-1 ha -1 month-1, which is similar to dust deposition rates monitored in arid and semiarid environments. However, these are not considered to be sufficient for present day loess genesis. Dust deposition was highest in summer because of the greater frequency of favourable dust transporting winds, …


Evidence Of Solar And Tropical-Ocean Forcing Of Hydroclimate Cycles In Southeastern Australia For The Past 6500 Years, Hamish A. Mcgowan, Samuel K. Marx, Joshua Soderholm, John Denholm Aug 2014

Evidence Of Solar And Tropical-Ocean Forcing Of Hydroclimate Cycles In Southeastern Australia For The Past 6500 Years, Hamish A. Mcgowan, Samuel K. Marx, Joshua Soderholm, John Denholm

Samuel K Marx

Evidence of solar and tropical‐ocean forcing of climate cycles has been found in numerous palaeoclimate records. Numerical modelling studies show physical mechanisms by which direct and indirect solar forcing may affect climate, while there is mounting evidence of solar forcing of tropical ocean‐atmosphere teleconnections. This study has developed a 6500 year record of dust deposition, a proxy for regional hydroclimate variability for the Snowy Mountains region of Australia. Spectral analysis of the record provides evidence of statistically significant cycles in dust deposition of 35–43 years, 62–73 years, 161 years and 2200 years. These correlate with variability in solar irradiance and …


Dinosaur Tracksites Of The Paluxy River Valley (Glen Rose Formation, Lower Cretaceous), Dinosaur Valley State Park, Somervell County, Texas., James O. Farlow, Mike O'Brien, Glenn J. Kuban, Benjamin F. Dattilo, K. T. Bates, Peter L. Falkingham, L. Pinuela, Amanda Rose, A. Freels, C. Kumagai, Courtney Libben, Justin Smith, J. Whitcraft Jul 2014

Dinosaur Tracksites Of The Paluxy River Valley (Glen Rose Formation, Lower Cretaceous), Dinosaur Valley State Park, Somervell County, Texas., James O. Farlow, Mike O'Brien, Glenn J. Kuban, Benjamin F. Dattilo, K. T. Bates, Peter L. Falkingham, L. Pinuela, Amanda Rose, A. Freels, C. Kumagai, Courtney Libben, Justin Smith, J. Whitcraft

Benjamin F. Dattilo

In 1940 R.T. Bird of the American Museum of Natural History collected segments of a sauropod and a theropod trackway from a site in the bed (Glen Rose Formation; Lower Cretaceous) of the Paluxy River, in what is now Dinosaur Valley State Park (Glen Rose, Texas, USA). However, Bird left undocumented thousands of other dinosaur footprints from this and other Paluxy tracksites. In 2008 and 2009 our international team carried out fieldwork to create detailed photomosaics of extant Paluxy tracksites, using GIS technology to combine these with historic maps and photographs. We also made photographs, tracings, LiDAR images, and measurements …


What Can We Learn From Confusing Olivella Columellaris And O. Semistriata (Olivellidae, Gastropoda), Two Key Species In Panamic Sandy Beach Ecosystems?, Allison I. Troost, Samantha D. Rupert, Ariel Z. Cyrus, Frank V. Paladino, Benjamin F. Dattilo, Winfried S. Peters Jul 2014

What Can We Learn From Confusing Olivella Columellaris And O. Semistriata (Olivellidae, Gastropoda), Two Key Species In Panamic Sandy Beach Ecosystems?, Allison I. Troost, Samantha D. Rupert, Ariel Z. Cyrus, Frank V. Paladino, Benjamin F. Dattilo, Winfried S. Peters

Benjamin F. Dattilo

Olivella columellaris (Sowerby 1825) and O. semistriata (Gray 1839) are suspension-feeding, swash-surfing snails on tropical sandy beaches of the east Pacific. While they often are the numerically dominant macrofaunal element in their habitats, their biology is poorly understood; the two species actually have been confused in all of the few publications that address their ecology. Frequent misidentifications in publications and collections contributed also to an overestimation of the geographic overlap of the two species. To provide a sound taxonomic basis for further functional, ecological, and evolutionary investigations, we evaluated the validity of diagnostic traits in wild populations and museum collections, …


Case 3270: Isometrinae Clark, 1917 (Ecinodermata, Crinoidea): Proposed Emendation Of Spelling To Isometrainae To Remove Homonymy With Isometrinae Kraepelin, 1891 (Arachnida, Scorpiones), Victor Fet, Charles G. Messing Jun 2014

Case 3270: Isometrinae Clark, 1917 (Ecinodermata, Crinoidea): Proposed Emendation Of Spelling To Isometrainae To Remove Homonymy With Isometrinae Kraepelin, 1891 (Arachnida, Scorpiones), Victor Fet, Charles G. Messing

Victor Fet

The purpose of this application, under Articles 55 and 29 of the Code, is to remove the homonymy between the crinoid subfamily name ISOMETRINAE Clark, 1917 (type genus Isometra Clark, 1908; family ANTEDONIDAE) and the scorpion subfamily name ISOMETRINAE Kraepelin, 1891 (type genus Isometrus Ehrenberg in Hemprich & Ehrenberg, 1828; family BUTHIDAE). It is proposed that the entire generic name of Isometra should be adopted as the stem, so that the correct spelling of the crinoid subfamily will become ISOMETRAINAE Clark, 1917.


Science And The Storms: The Usgs Response To The Hurricanes Of 2005 - Chapter Six: Ecological Impacts, William Conner, Stephen Faulkner, Wylie Barrow, Brady Couvillion, Lori Randall, Michael Baldwin Jun 2014

Science And The Storms: The Usgs Response To The Hurricanes Of 2005 - Chapter Six: Ecological Impacts, William Conner, Stephen Faulkner, Wylie Barrow, Brady Couvillion, Lori Randall, Michael Baldwin

William Conner

Ecological impacts from the hurricanes of 2005 affected both vegetation and the animals that depend on coastal habits on land and in water. Discussed in this section are migratory birds, coastal marsh vegetation, chenier forests, coastal floodplain forests, mangrove forests, estuaries, and the endangered manatee.


Modeled Impacts Of Cover Crops And Vegetative Barriers On Corn Stover Availability And Soil Quality, Ian J. Bonner, David J. Muth Jr., Joshua B. Koch, Douglas L. Karlen May 2014

Modeled Impacts Of Cover Crops And Vegetative Barriers On Corn Stover Availability And Soil Quality, Ian J. Bonner, David J. Muth Jr., Joshua B. Koch, Douglas L. Karlen

Douglas L Karlen

Environmentally benign, economically viable, and socially acceptable agronomic strategies are needed to launch a sustainable lignocellulosic biofuel industry. Our objective was to demonstrate a landscape planning process that can ensure adequate supplies of corn (Zea mays L.) stover feedstock while protecting and improving soil quality. The Landscape Environmental Assessment Framework (LEAF) was used to develop land use strategies that were then scaled up for five U.S. Corn Belt states (Nebraska, Iowa, Illinois, Indiana, and Minnesota) to illustrate the impact that could be achieved. Our results show an annual sustainable stover supply of 194 million Mg without exceeding soil erosion T …


The Public Health Impacts Of Concentrated Animal Feeding Operations On Local Communities, Michael Greger, Gowri Koneswaran May 2014

The Public Health Impacts Of Concentrated Animal Feeding Operations On Local Communities, Michael Greger, Gowri Koneswaran

Michael Greger, MD, FACLM

Large-scale farm animal production facilities, also known as concentrated animal feeding operations (CAFOs), release a significant amount of contaminants into the air and water. Adverse health effects related to exposure to these contaminants among CAFO workers have been welldocumented; however, less is known about their impact on the health of residents in nearby communities. Epidemiological research in this area suggests that neighboring residents are at increased risk of developing neurobehavioral symptoms and respiratory illnesses, including asthma. Additional research is needed to better understand community-scale exposures and health outcomes related to the management practices and emissions of CAFOs.


Laboratory Routines Cause Animal Stress, Jonathan P. Balcombe, Neal D. Barnard, Chad Sandusky May 2014

Laboratory Routines Cause Animal Stress, Jonathan P. Balcombe, Neal D. Barnard, Chad Sandusky

Jonathan Balcombe, PhD

Eighty published studies were appraised to document the potential stress associated with three routine laboratory procedures commonly performed on animals: handling, blood collection, and orogastric gavage. We defined handling as any non-invasive manipulation occurring as part of routine husbandry, including lifting an animal and cleaning or moving an animal's cage. Significant changes in physiologic parameters correlated with stress (e.g., serum or plasma concentrations of corticosterone, glucose, growth hormone or prolactin, heart rate, blood pressure, and behavior) were associated with all three procedures in multiple species in the studies we examined. The results of these studies demonstrated that animals responded with …


2-Acylamido Analogues Of N-Acetylglucosamine Prime Formation Of Chitin Oligosaccharides By Yeast Chitin Synthase 2, Jacob Gyore, Archana R. Parameswar, Carleigh F. F. Hebbard, Younghoon Oh, Erfei Bi, Alexei V. Demchenko, Neil P. Price, Peter Orlean May 2014

2-Acylamido Analogues Of N-Acetylglucosamine Prime Formation Of Chitin Oligosaccharides By Yeast Chitin Synthase 2, Jacob Gyore, Archana R. Parameswar, Carleigh F. F. Hebbard, Younghoon Oh, Erfei Bi, Alexei V. Demchenko, Neil P. Price, Peter Orlean

Alexei Demchenko

Chitin, a homopolymer of β1,4-linked N-acetylglucosamine (GlcNAc) residues, is a key component of the cell walls of fungi and the exoskeletons of arthropods. Chitin synthases transfer GlcNAc from UDP-GlcNAc to preexisting chitin chains in reactions that are typically stimulated by free GlcNAc. The effect of GlcNAc was probed by using a yeast strain expressing a single chitin synthase, Chs2, by examining formation of chitin oligosaccharides (COs) and insoluble chitin, and by replacing GlcNAc with 2-acylamido analogues of GlcNAc. Synthesis of COs was strongly dependent on inclusion of GlcNAc in chitin synthase incubations, and N,N′-diacetylchitobiose (GlcNAc2) was the major reaction product. …


Molecular Engineering Of Side-Chain Liquid Crystalline Polymers By Living Polymerizations, Coleen Pugh, Alan L. Kiste Apr 2014

Molecular Engineering Of Side-Chain Liquid Crystalline Polymers By Living Polymerizations, Coleen Pugh, Alan L. Kiste

Coleen Pugh

“Living” anionic, cationic, metalloporphyrin and ring-opening metathesis polymerizations have been used to prepare well-defined side-chain liquid crystalline homopolymers, block and graft copolymers and statistical copolymers. This paper analyzes their successes and failures by reviewing the mechanistic aspects and experimental conditions of each type of polymerization, and identifies other classes of mesogenic monomers that could be polymerized in a controlled manner in the future. The emerging structure/property relationships are then identified using well-defined SCLCPs in which only one structural feature is varied while all others remain constant. The thermal transitions of liquid crystalline polymethacrylates, polynorbomenes and poly(viny1 ether)s reach their limiting …


New Multidetector Solution Could Lead To Safer Alternatives To Faulty Silicone Breast Implants, Judit D. Puskas, Geof Wyatt Apr 2014

New Multidetector Solution Could Lead To Safer Alternatives To Faulty Silicone Breast Implants, Judit D. Puskas, Geof Wyatt

Judit E. Puskas

The article discusses the effort of the University of Akron's Department of Chemical and Biomolecular Engineering to pursue research which aims to reduce or eliminate capsular contracture associated with breast implants. It notes that the new multidetector nanotechnology developed by researchers can be better alternative to silicone gel-filled breast implants. It mentions that the new technology can also help in early diagnosis and imaging of breast cancer.


New Data On Occurrences Of The Devonian Rugose Coral Calceola In Belgium, Anthony J. Wright, M Coen-Aubert, P Bultynck, A P. Van Viersen Apr 2014

New Data On Occurrences Of The Devonian Rugose Coral Calceola In Belgium, Anthony J. Wright, M Coen-Aubert, P Bultynck, A P. Van Viersen

Anthony Wright

Opercula and corallites of Calceola sandalina from the late Eifelian and early Givetian (Middle Devonian) Hanonet Formation of Belgium are illustrated. The few previous illustrations of calceoloid corals from the Devonian of Belgium did not include opercula showing the generically diagnostic morphological features, so for the first time the presence of the genus and species in Belgium is confirmed. One important corallite shows the alar septum and insertion of septa on the external surface of the counter face adjacent to the alar septum.


Late Llandovery (Early Silurian) Dendroid Graptolites From The Cotton Formation Near Forbes, New South Wales, R B. Rickards, Anthony J. Wright, G Thomas Apr 2014

Late Llandovery (Early Silurian) Dendroid Graptolites From The Cotton Formation Near Forbes, New South Wales, R B. Rickards, Anthony J. Wright, G Thomas

Anthony Wright

A well-preserved dendroid graptolite fauna of Early Silurian (late Llandovery: probable turriculatus graptolite zone) age is described from the Cotton Formation near Forbes, New South Wales. A possible rhabdopleuran hemichordate is described from Australia for the fi rst time. The fauna consists of 13 taxa as follows: Dendrograptus sp. aff. D. avonleaensis, Dictyonema zalasiewiczi sp. nov., Dictyonema sp. aff. D. paululum australis, Dictyonema paululum australis, Dictyonema sp. aff. D. sp. cf. D. venustus of Bulman (?ssp. nov.), Dictyonema venustum, Dictyonema sp. cf. D. falciferum, Callograptus bridgecreekensis, Callograptus rigbyae, Callograptus sp. aff. C. ulahensis, Stelechocladia sp. cf. S. praeattenuata, Acanthograptus praedeckeri …


Phylum Arthropoda, Subphylum Trilobitomorpha: Trilobites, Anthony J. Wright, Roger A. Cooper Apr 2014

Phylum Arthropoda, Subphylum Trilobitomorpha: Trilobites, Anthony J. Wright, Roger A. Cooper

Anthony Wright

This volume is the second of three that provide a complete review and inventory of New Zealand's entire living and fossil biodiversity - an international effort involving more than 220 New Zealand and overseas specialists and the most comprehensive of its kind in the world. Together, the three volumes will list every one of the almost 55,000 known species of New Zealand's animals, plants, fungi and micro-organisms. Volume 2 mostly deals with the major branch of the animal kingdom known as Ecdysozoa (moulting animals), which includes arachnids, centipedes and millipedes, crustaceans and insects. It also includes the enigmatic phylum Chaetognatha …