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Dna Replication In The Human Malaria Parasite And Potential For Novel Drug Development, J Li

School of Biomedical Sciences

Rather than simply "itemising" the replication steps and the proteins involved, replication is tackled from a novel perspective. The book provides logical groupings of processes based upon biochemical similarities.

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Polar Diversity Of The Tardigrada: A Combined Morphological / Molecular Approach., Cj Sands, Sj Mcinnes, Nj Marley, Wp Goodall-Copestake, Et Al

School of Biological and Marine Sciences

POLAR DIVERSITY OF THE TARDIGRADA: A COMBINED MORPHOLOGICAL / MOLECULAR APPROACH C.J. Sands1 , S.J. McInnes1 , N.J. Marley2 , W.P. Goodall-Copestake1 , P. Convey1 , L. Linse1 1 - Natural Environment Research Council, British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET, United Kingdom 2 - Marine Biology and Ecology Research Centre, University of Plymouth, Drake Circus, Plymouth, PL4 8AA, United Kingdom [email protected] Examining the spatial distributions of organisms can provide information regarding their evolutionary history. We are investigating the origins and the processes that influence the contemporary distribution and diversity of Antarctic terrestrial biota. Tardigrades were chosen …

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Web 3d For Public, Environmental And Occupational Health: Early Examples From Second Life®., Boulos Mn Kamel, Rameshsharma Ramloll, Ray Jones, Susan Toth-Cohen

School of Nursing and Midwifery

No abstract provided.

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Organisational Commitment: Buffer Of Work Stress?, Laura Jones

The Plymouth Student Scientist

Work stress has been linked to negative health outcomes; however, evidence has shown that organisational commitment can act as a buffer to work stress. This is known as the buffering hypothesis of commitment. It was hypothesised that affective commitment would buffer negative effects of specific work stressors and reduce ill health. A convenience sample of 52 urban bus drivers (44 male and 8 female) completed the ASSET questionnaire (an organisational stress screening tool). Limited evidence to support the buffering hypothesis was found, although high levels of commitment were associated with low levels of psychological ill health. Suggestive gender differences were …

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Undergraduate Research Journals: Praising Success But Recognising Doubt And Even "Failure", Alan Jenkins

The Plymouth Student Scientist

Editorial

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Testing The Degradation Rates Of Degradable, Non-Degradable And Bio-Degradable Plastics Within Simulated Marine Environments, Simon T. Wellfair

The Plymouth Student Scientist

Plastics are a serious problem in the environment today. They cause a number of difficulties for organisms in the water which often mistake them for food and suffocate, or they become entangled in them and drown. Plastics are highly versatile and hard wearing, they survive longer than their use requires and often end up in the environment. One of the largest forms of plastic pollution is plastic bags. Many plastics bags have been deemed ‘degradable’ and have been given a time frame in which they will break down, but this does not suggest the type of environments in which they …

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The Haemolytic Effect Of Verapamil On Erythrocytes Exposed To Varying Osmolarity, Tim Watts, Richard Handy

The Plymouth Student Scientist

The haemolytic effect of verapamil on red blood cells (RBCs) exposed to varying osmolarity was investigated. The experimental approach used a modified red cell haemolysis assay with concentrations of verapamil ranging from 50–1500 lM compared to drug free controls. The timecourse of haemolytic effects was also investigated. We also briefly determined the haemolytic effects of verapamil in Ca2+-free conditions (with added EGTA). In conditions representing decreasing osmolarity (dilution from 140–0 mM NaCl) there was a significant increase in erythrocyte haemolysis that was also dependent on verapamil concentration (ANOVA, p < 0.05). The red cells also showed a significantly increased rate of haemolysis over 5 h with increasing verapamil concentration (ANOVA, p < 0.05). The degree of RBC hypotonic haemolysis was significantly increased in a Ca2+-free medium (+EGTA) compared to normal saline and this effect was exacerbated by additions of verapamil (ANOVA, p < 0.05). Overall the data suggested that verapamil can cause haemolysis of RBCs in a predictable time- and concentration-dependent manner, and that verapamil increases the fragility of the erythrocytes further during hypotonic osmotic stress and Ca2+-free conditions. The mechanism of verapamildependent haemolysis could be directly related to the observed biphasic concentration-effect and could consequently involve several ion transport pathways.

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Expression And Localisation Of Wave Isoforms In Human Schwann And Schwannoma Cells, Marei Caroline Schmid

The Plymouth Student Scientist

Schwannoma, the main tumours associated with Neurofibromatosis Type II, are caused by loss of function mutations in the NF2 gene, encoding for the tumour suppressor Merlin. Schwannoma cells display protrusive structures, due to deregulation of the cytoskeleton. The cytoskeleton is controlled by small Rho GTPases, such as Rac1 and Cdc42, known to be activated continuously in merlin-deficient human schwannoma cells (NF2-/-). Downstream Rac signalling leads to the activaton of Wave signalling complexes, which have been shown to bind and activate the Arp2/3 complex, a crucial regulator of the actin cytoskeleton that is involved in formation of protrusive structures. This investigation …

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Seeing The Bigger Picture: An Amblyopic Advantage In The Global Integration Of Moving Visual Information?, Hannah Jeffery

The Plymouth Student Scientist

Devices used to incorporate global information by normal and amblyopic eyes were investigated using the Classification Image (CI) technique. An orientation task with randomly orientated tilting Gabor patches and a motion-direction task using randomly directed moving discs were utilized. Participants judged the near-threshold average global orientation or motion-direction in each. CIs were calculated, adding noise samples eliciting correct responses and subtracting noise samples producing incorrect responses. Results illustrated normal participants had consistently narrow perceptive fields as was the case for amblyopes in the orientation task. For global motion-direction judgements, amblyopic perceptive fields were far wider, illustrating sparse sampling of elements. …

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Taking Stock Of The World's Species, Samantha Russell

The Plymouth Student Scientist

Scientists are to establish a giant catalogue of life - to, in effect, “barcode” every species on Earth. This poster aims to provide an overview of DNA barcoding: what is it? and why is it controversial?

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An Investigation Into The Cardiac Implications Of Bradycardia In Marine Sports Practitioners, Antony Cole

The Plymouth Student Scientist

This study investigated the effect of the mammalian diving reflex (MDR) on the R-R intervals, mean heart rate (MHR) and mean arterial blood pressure (MABP) on 40 healthy subjects. Two groups were compared a group of SCUBA divers and a group of non SCUBA divers. Each group consisted of ten males and ten females. Subjects completed seven protocols: three in air; breathing (BA); apnea (AA); breathing through a snorkel (BSA) and three facially immersed; breathing through a snorkel (23±1°C) (BSI); apnea (35±1°C) (AWW); apnea (23±1°C) (AWR) apnea (10±1°C) (AWC). A negative correlation was observed between diving experience and bradycardia. A …

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American Mink (Mustela Vison) And Its Impact On Native Species In The Uk, Alex W. Rey

The Plymouth Student Scientist

Introduced alien species are recognised to be a major threat to native biodiversity. The American mink (Mustela vison) is a highly adaptable, naturalised predator in the UK, introduced as part of the fur trade in the 1920‟s. The species became established in the wild in the 1950‟s through purposeful releases and escapes and since establishing the mink has been held accountable for the decline of many native species, most notably the water vole (Arvicola terrestris). There are currently nine species of carnivore in the UK, and American mink presents competition for native predators, particularly those that have similar lifestyles. In …

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The Role Of Zooxanthellae In Marine Invertebrates, Jonathan Wallen

The Plymouth Student Scientist

The importance of zooxanthellae in marine environments cannot be understated. Their role as a source of nutritive energy to corals underpins the success of reef-building systems worldwide, forming some of the most productive ecosystems on earth. The diversity of these unicellular symbiotic algae, which belong to the genus Symbiodinium, is enormous. Multiple hosts, multiple types of algae and the diverse habitats in which these organisms are found suggests a diverse reservoir of symbiont types in almost every region. This review focuses on the functional and genetic diversity of Symbiodinium, the specificity and flexibility of the host-algal association, and the implications …

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Is There A Visitor Effect On Abyssinian Ground Hornbills (Bucorvus Abyssinicus), Papuan Wreathed Hornbills (Aceros Plicatus), Wrinkled Hornbills (Aceros Corrugatus) And Toco Toucans (Ramphastos Toco) In A Captive Zoo Environment?, Susanna Frances Thicks

The Plymouth Student Scientist

Research into the possible effects that zoo visitors have on the captive animals they come to visit is still relatively poorly understood. Most of the studies all ready completed have used non-human primate subjects, but there is a distinct lack of studies using non-primate species. One of the groups that are in particular need of this kind of research is birds. This study examines a potential visitor effect in captive Abyssinian Ground Hornbills (Bucorvus abyssinicus), Papuan Wreathed Hornbills (Aceros plicatus), Wrinkled Hornbills (Aceros corrugatus) and Toco Toucans (Ramphastos toco) at Paignton Zoo Environmental Park®. This study also investigates the evenness …

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The Effect Of Starvation On The Size Of Mussels Selected By The Green Shore Crab, Carcinus Maenas, Brecht Morris

The Plymouth Student Scientist

The foraging behaviour of the green shore crabs, Carcinus maenas, of 24-26mm carapace width was observed over a 6 day starvation period. Edible mussels, Mytilus edulis, for each millimetre interval from 5-25mm were used to determine how prey size selection was effected by starvation. The most profitable mussel size for the studied crab size is approximately 9mm. At low starvation levels mussel size selection was relatively specific with the majority of selected mussels ranging in size from 7-12mm. Increased starvation caused greater variation in size selection with the majority of selected mussels ranging from 7-16mm, with a higher proportion of …

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Does He Know I'M His Brother? A Multi-Method Inquiry Into Sibling Relationships Involving Children With Disabilities, Annabel David

The Plymouth Student Scientist

A mixed method approach was used to investigate the impact of disability and family-size on sibling relationships. The quantitative component used a questionnaire to analyse 191 sibling dyads in terms of companionship, empathy, teaching / caring, rivalry, aggression / conflict, and avoidance. Lower levels of positive behaviours and higher levels of negative behaviours were reported when one of the children was disabled. Non-disabled children displayed more positive and less negative behaviour towards their disabled siblings in three-child-families, compared with those in two-child-families. The qualitative component consisted of interviews with four families and the data was analysed using a grounded theory …

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Variation In Both Male And Female Secondary Sexual Characters In The Diving Beetle, Agabus Bipustulatus (L.) (Coleoptera: Dytiscidae), William James Howe

The Plymouth Student Scientist

Sexual conflict and intersexual arms races occur due to the differing evolutionary interests between the sexes. Under the model of sexual conflict it is predicted that this will lead to sexual dimorphism, common in diving beetles, where males have suckers which they use to attach to the females’ dorsal surface to potentially increase their copulatory ability. These are often met by female counteradaptations in an attempt to avoid multiple and potentially costly matings. This can result in a cyclical battle of responses in both sexes. Within the widely distributed species, Agabus bipustulatus there is known variation in female sculpture from …

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A Critical Evaluation Of The Symbiotic Association Between Tropical Tube-Dwelling Polychaetes And Their Hermatypic Coral Hosts, With A Focus On Spirobranchus Giganteus (Pallas, 1766), Sonia Rowley

The Plymouth Student Scientist

Coral reefs are high in species diversity with a low effective population size for most species and a high incidence of specific co-evolved relationships. Hermatypic corals are associated with, and attract a variety of, symbionts and commensals which helps to maintain coral reef biodiversity. However, little is known about such associations. Tropical tube-dwelling polychaetes provide an interesting surrogate in the enhancement of current understanding of such associations posing the question: what is the nature of the symbiotic association between tropical tube-dwelling polychaetes and their hermatypic coral hosts? This question is addressed by reviewing the life history and ecology of the …

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Output Feedback Nn Control For Two Classes Of Discrete-Time Systems With Unknown Control Directions In A Unified Approach, C Yang, Ss Ge, C Xiang, Ty Chai, Th Lee

School of Engineering, Computing and Mathematics

In this paper, output feedback adaptive neural network (NN) controls are investigated for two classes of nonlinear discrete-time systems with unknown control directions: 1) nonlinear pure-feedback systems and 2) nonlinear autoregressive moving average with exogenous inputs (NARMAX) systems. To overcome the noncausal problem, which has been known to be a major obstacle in the discrete-time control design, both systems are transformed to a predictor for output feedback control design. Implicit function theorem is used to overcome the difficulty of the nonaffine appearance of the control input. The problem of lacking a priori knowledge on the control directions is solved by …

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Proteomic Profiling Of Plasmodium Sporozoite Maturation Identifies New Proteins Essential For Parasite Development And Infectivity, E Lasonder, Cj Janse, G-J Van Gemert, Gr Mair, Et Al

School of Biomedical Sciences

Plasmodium falciparum sporozoites that develop and mature inside an Anopheles mosquito initiate a malaria infection in humans. Here we report the first proteomic comparison of different parasite stages from the mosquito -- early and late oocysts containing midgut sporozoites, and the mature, infectious salivary gland sporozoites. Despite the morphological similarity between midgut and salivary gland sporozoites, their proteomes are markedly different, in agreement with their increase in hepatocyte infectivity. The different sporozoite proteomes contain a large number of stage specific proteins whose annotation suggest an involvement in sporozoite maturation, motility, infection of the human host and associated metabolic adjustments. Analyses …

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Interdependent Utilities: How Social Ranking Affects Choice Behavior, Nadège Bault, Giorgio Coricelli, Aldo Rustichini

School of Psychology

No abstract provided.

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Board Composition, Ownership Structure And Dividend Policies In An Emerging Market, O Abdelsalam, A El‐Masry, S Elsegini

Plymouth Business School

Purpose The purpose of this study is to examine dividend policies in an emerging capital market, in a country undergoing a transitional period. Design/methodology/approach Using pooled cross‐sectional observations from the top 50 listed Egyptian firms between 2003 and 2005, this study examines the effect of board of directors' composition and ownership structure on dividend policies in Egypt. Findings It is found that there is a significant positive association between institutional ownership and firm performance, and both dividend decision and payout ratio. The results confirm that firms with a higher return on equity and a higher institutional ownership distribute higher levels …

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The Impact Of Corporate Governance On The Timeliness Of Corporate Internet Reporting By Egyptian Listed Companies, A Ezat, Aa El-Masry

Plymouth Business School

Purpose This study seeks to examine the key factors that affect the timeliness of corporate internet reporting (CIR) by the Egyptian listed corporations on the Cairo and Alexandria Stock Exchange. Design/methodology/approach The authors use firm characteristics and corporate governance variables to investigate the influence on the timeliness of CIR. They also develop a disclosure index to measure the timeliness of CIR for the listed Egyptian corporations. Findings The primary analysis finds a significant relationship between the timeliness of CIR and firm size, type of industry, liquidity, ownership structure, board composition and board size. The results indicate that firms typically in …

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Loss Of Mediterranean Marine Biodiversity In A High-Co2 World, Jm Hall-Spencer, R Rodolfo-Metalpa

School of Biological and Marine Sciences

No abstract provided.

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Neural Nets Versus Conventional Techniques In Credit Scoring In Egyptian Banking, H Abdou, J Pointon, A El-Masry

Plymouth Business School

Neural nets have become one of the most important tools using in credit scoring. Credit scoring is regarded as a core appraised tool of commercial banks during the last few decades. The purpose of this paper is to investigate the ability of neural nets, such as probabilistic neural nets and multi-layer feed-forward nets, and conventional techniques such as, discriminant analysis, probit analysis and logistic regression, in evaluating credit risk in Egyptian banks applying credit scoring models. The credit scoring task is performed on one bank's personal loans' data-set. The results so far revealed that the neural nets-models gave a better …

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Adaptive Predictive Control Using Neural Network For A Class Of Pure-Feedback Systems In Discrete-Time, Ss Ge, C Yang, Th Lee

School of Engineering, Computing and Mathematics

In this paper, adaptive neural network (NN) control is investigated for a class of nonlinear pure-feedback discrete-time systems. By using prediction functions of future states, the pure-feedback system is transformed into an n -step-ahead predictor, based on which state feedback NN control is synthesized. Next, by investigating the relationship between outputs and states, the system is transformed into an input-output predictor model, and then, output feedback control is constructed. To overcome the difficulty of nonaffine appearance of the control input, implicit function theorem is exploited in the control design and NN is employed to approximate the unknown function in the …

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Comparison Of Health And Physical Education Policies With Practices: An Evaluation Of School Responses Within Three Brisbane Catholic Education (Bce) Primary Schools (2005)., Tj Lynch

Plymouth Institute of Education

The purpose of this study was to compare the ideals of the Queensland P-10 Health and Physical Education (HPE) syllabus as a curriculum policy, with what was happening in practice, the teaching of Health and Physical Education in schools. It was envisaged that through this process good practice within schools could be identified and its implementation promoted. This paper is the first research within Queensland to investigate the ideals for quality Health and Physical Education, in comparison to what is actually occurring in practice.

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Impact Of Environmental Production Conditions On Productivity And Efficiency: A Case Study Of Wheat Farmers In Bangladesh, S Rahman, Mk Hasan

School of Geography, Earth and Environmental Sciences

Environmental conditions significantly affect production, but are often ignored in studies analysing productivity and efficiency leading to biased results. In this study, we examine the influence of selected environmental factors on productivity and efficiency in wheat farming in Bangladesh. Results reveal that environmental production conditions significantly affect the parameters of the production function and technical efficiency, as well as correlates of inefficiency. Controlling for environmental production conditions improves technical efficiency by 4 points (p<0.01) from 86% to 90%. Large farms are more efficient relative to small and medium sized farms (p<0.01 and 0.05), with no variation among regions. Policy implications include soil fertility improvement through soil conservation and crop rotation, improvement in managerial practices through extension services and adoption of modern technologies, promotion of education, strengthening the research-extension link, and development of new varieties that have higher yield potential and are also suitable for marginal areas.

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Young Devon Mental Health Housing Service Evaluation Project, H Donnellan, G Blakely

School of Health Professions

No abstract provided.

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Management Recommendations For Sustainable Exploitation Of Mussel Seed In The Irish Sea, Ja Maguire, Am Knights, M O'Toole, G Burnell, Et Al

School of Biological and Marine Sciences

No abstract provided.

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Full-Text Articles in Entire DC Network

Dna Replication In The Human Malaria Parasite And Potential For Novel Drug Development, J Li

School of Biomedical Sciences

Polar Diversity Of The Tardigrada: A Combined Morphological / Molecular Approach., Cj Sands, Sj Mcinnes, Nj Marley, Wp Goodall-Copestake, Et Al

School of Biological and Marine Sciences

Web 3d For Public, Environmental And Occupational Health: Early Examples From Second Life®., Boulos Mn Kamel, Rameshsharma Ramloll, Ray Jones, Susan Toth-Cohen

School of Nursing and Midwifery

Organisational Commitment: Buffer Of Work Stress?, Laura Jones

The Plymouth Student Scientist

Undergraduate Research Journals: Praising Success But Recognising Doubt And Even "Failure", Alan Jenkins

The Plymouth Student Scientist

Testing The Degradation Rates Of Degradable, Non-Degradable And Bio-Degradable Plastics Within Simulated Marine Environments, Simon T. Wellfair

The Plymouth Student Scientist

The Haemolytic Effect Of Verapamil On Erythrocytes Exposed To Varying Osmolarity, Tim Watts, Richard Handy

The Plymouth Student Scientist

Expression And Localisation Of Wave Isoforms In Human Schwann And Schwannoma Cells, Marei Caroline Schmid

The Plymouth Student Scientist

Seeing The Bigger Picture: An Amblyopic Advantage In The Global Integration Of Moving Visual Information?, Hannah Jeffery

The Plymouth Student Scientist

Taking Stock Of The World's Species, Samantha Russell

The Plymouth Student Scientist

An Investigation Into The Cardiac Implications Of Bradycardia In Marine Sports Practitioners, Antony Cole

The Plymouth Student Scientist

American Mink (Mustela Vison) And Its Impact On Native Species In The Uk, Alex W. Rey

The Plymouth Student Scientist

The Role Of Zooxanthellae In Marine Invertebrates, Jonathan Wallen

The Plymouth Student Scientist

Is There A Visitor Effect On Abyssinian Ground Hornbills (Bucorvus Abyssinicus), Papuan Wreathed Hornbills (Aceros Plicatus), Wrinkled Hornbills (Aceros Corrugatus) And Toco Toucans (Ramphastos Toco) In A Captive Zoo Environment?, Susanna Frances Thicks

The Plymouth Student Scientist

The Effect Of Starvation On The Size Of Mussels Selected By The Green Shore Crab, Carcinus Maenas, Brecht Morris

The Plymouth Student Scientist

Does He Know I'M His Brother? A Multi-Method Inquiry Into Sibling Relationships Involving Children With Disabilities, Annabel David

The Plymouth Student Scientist

Variation In Both Male And Female Secondary Sexual Characters In The Diving Beetle, Agabus Bipustulatus (L.) (Coleoptera: Dytiscidae), William James Howe

The Plymouth Student Scientist

A Critical Evaluation Of The Symbiotic Association Between Tropical Tube-Dwelling Polychaetes And Their Hermatypic Coral Hosts, With A Focus On Spirobranchus Giganteus (Pallas, 1766), Sonia Rowley

The Plymouth Student Scientist

Output Feedback Nn Control For Two Classes Of Discrete-Time Systems With Unknown Control Directions In A Unified Approach, C Yang, Ss Ge, C Xiang, Ty Chai, Th Lee

School of Engineering, Computing and Mathematics

Proteomic Profiling Of Plasmodium Sporozoite Maturation Identifies New Proteins Essential For Parasite Development And Infectivity, E Lasonder, Cj Janse, G-J Van Gemert, Gr Mair, Et Al

School of Biomedical Sciences

Interdependent Utilities: How Social Ranking Affects Choice Behavior, Nadège Bault, Giorgio Coricelli, Aldo Rustichini

School of Psychology

Board Composition, Ownership Structure And Dividend Policies In An Emerging Market, O Abdelsalam, A El‐Masry, S Elsegini

Plymouth Business School

The Impact Of Corporate Governance On The Timeliness Of Corporate Internet Reporting By Egyptian Listed Companies, A Ezat, Aa El-Masry

Plymouth Business School

Loss Of Mediterranean Marine Biodiversity In A High-Co2 World, Jm Hall-Spencer, R Rodolfo-Metalpa

School of Biological and Marine Sciences

Neural Nets Versus Conventional Techniques In Credit Scoring In Egyptian Banking, H Abdou, J Pointon, A El-Masry

Plymouth Business School

Adaptive Predictive Control Using Neural Network For A Class Of Pure-Feedback Systems In Discrete-Time, Ss Ge, C Yang, Th Lee

School of Engineering, Computing and Mathematics

Comparison Of Health And Physical Education Policies With Practices: An Evaluation Of School Responses Within Three Brisbane Catholic Education (Bce) Primary Schools (2005)., Tj Lynch

Plymouth Institute of Education

Impact Of Environmental Production Conditions On Productivity And Efficiency: A Case Study Of Wheat Farmers In Bangladesh, S Rahman, Mk Hasan

School of Geography, Earth and Environmental Sciences

Young Devon Mental Health Housing Service Evaluation Project, H Donnellan, G Blakely

School of Health Professions

Management Recommendations For Sustainable Exploitation Of Mussel Seed In The Irish Sea, Ja Maguire, Am Knights, M O'Toole, G Burnell, Et Al

School of Biological and Marine Sciences