• A Fast New Numerical Tool for Designing Pre-stressed Dies for Backward Extrusion: Part 1: Die Behaviour

      Bonnavand, F.; Bramley, Alan N.; Mynors, Diane J. (Professional Engineering Publishing, 2001)
      Prestressed die inserts are often used in the forging of axisymmetric parts. Their use enhances overall tool economy and can enhance the quality of the finished forging. The design of tooling that incorporates prestressed die inserts is, however, complex. The complexity arises from the interrelated phenomena that occur within the dies during the forging process. As a result, it is not possible to obtain an analytical expression for critical parameters such as die stresses and deflections. This paper shows the limitations of currently used design methods, and identifies, for the backward extrusion process, which physical phenomena should be taken into account when designing prestressed tooling. (Professional Engineering Publishing)
    • A fast new numerical tool for designing prestressed dies for backward extrusion: Part 2: numerical analysis

      Bonnavand, F.; Bramley, Alan N.; Mynors, Diane J. (Professional Engineering Publishing, 2001)
      The economics of forging requires tools to be designed to ensure maximum service life. Ideally, this should be achieved by determining the maximum equivalent stress experienced by tools during service. However, the determination of the maximum equivalent stress in the dies through numerical simulations is very time consuming. For the case of a backward extrusion process, this paper proposes a method for its determination that is based on an analytical function of the process parameters. This function was obtained by generating a database that includes the maximum equivalent stress for a large range of process parameters. This database was then modelled by a function determined through statistical analysis. (Professional Engineering Publishing)
    • A Finite Element Analysis of the Stress Intensity Resulting from Single-Edge Pre-Cracked Beam Loading Conditions

      Kibble, Kevin A.; Turner, D. (ASTM International, 2001)
      The single-edge precracked-beam (SEPB) fracture toughness method has been investigated using finite element methods to analyze the stress intensity (K1) resulting from variations in bridge span, punch length, and virtual crack length. A two-dimensional half-plane, semi-infinite model was used to approximate the stress intensity from a fit of the nodal displacements of a crack face under SEPB loading conditions. The finite element method models the crack in situ, using six-node triangular elements specified around a singular point that simulates the crack tip. The analysis reveals that for increasing virtual crack length (), the stress intensity increases to a maximum where / = 0. With further increasing virtual crack length, the stress intensity decreases. The inflection point differs for varying span and fixed punch length, and for varying punch lengths with fixed span. The resulting stress intensities per new ton force loading are presented in tabular and graphical form. The presented series of graphs can be used to explore variations in precracking parameters. This finite element analysis provides useful data for those developing or adopting the SEPB fracture toughness measurement technique.
    • A high-throughput synthetic platform enables the discovery of proteomimetic cell penetrating peptides and bioportides

      Jones, Sarah; Osman, Shaimaa; Howl, John (Springer-Verlag, 2018-02-19)
      Collectively, cell penetrating peptide (CPP) vectors and intrinsically active bioportides possess tremendous potential for drug delivery applications and the discrete modulation of intracellular targets including the sites of protein–protein interactions (PPIs). Such sequences are usually relatively short (< 25 AA), polycationic in nature and able to access the various intracellular compartments of eukaryotic cells without detrimental influences upon cellular biology. The high-throughput platform for bioportide discovery described herein exploits the discovery that many human proteins are an abundant source of potential CPP sequences which are reliably predicted using QSAR algorithms or other methods. Subsequently, microwave-enhanced solid phase peptides synthesis provides a high-throughput source of novel proteomimetic CPPs for screening purposes. By focussing upon cationic helical domains, often located within the molecular interfaces that facilitate PPIs, bioportides which act by a dominant-negative mechanism at such sites can be reliably identified within small number libraries of CPPs. Protocols that employ fluorescent peptides, routinely prepared by N-terminal acylation with carboxytetramethylrhodamine, further enable both the quantification of cellular uptake kinetics and the identification of specific site(s) of intracellular accretion. Chemical modifications of linear peptides, including strategies to promote and stabilise helicity, are compatible with the synthesis of second-generation bioportides with improved drug-like properties to further exploit the inherent selectivity of biologics.
    • A machine-learning approach to negation and speculation detection for sentiment analysis

      Cruz, Noa P.; Taboada, Maite; Mitkov, Ruslan; Department of Information Technology; University of Huelva; Huelva Spain; Department of Linguistics; Simon Fraser University; Vancouver Canada; Research Institute for Information and Language Processing; University of Wolverhampton; Wolverhampton UK (2015-05-13)
      Recognizing negative and speculative information is highly relevant for sentiment analysis. This paper presents a machine-learning approach to automatically detect this kind of information in the review domain. The resulting system works in two steps: in the first pass, negation/speculation cues are identified, and in the second phase the full scope of these cues is determined. The system is trained and evaluated on the Simon Fraser University Review corpus, which is extensively used in opinion mining. The results show how the proposed method outstrips the baseline by as much as roughly 20% in the negation cue detection and around 13% in the scope recognition, both in terms of F1. In speculation, the performance obtained in the cue prediction phase is close to that obtained by a human rater carrying out the same task. In the scope detection, the results are also promising and represent a substantial improvement on the baseline (up by roughly 10%). A detailed error analysis is also provided. The extrinsic evaluation shows that the correct identification of cues and scopes is vital for the task of sentiment analysis.
    • A model for Android and iOS applications risk calculation: CVSS analysis and enhancement using case-control studies

      Petraityte, Milda; Dehghantanha, Ali; Epiphaniou, Gregory (Elsevier, 2018)
      Various researchers have shown that the Common Vulnerability Scoring System (CVSS) has many drawbacks and may not provide a precise view of the risks related to software vulnerabilities. However, many threat intelligence platforms and industry-wide standards are relying on CVSS score to evaluate cyber security compliance. This paper suggests several improvements to the calculation of Impact and Exploitability sub-scores within the CVSS, improve its accuracy and help threat intelligence analysts to focus on the key risks associated with their assets. We will apply our suggested improvements against risks associated with several Android and iOS applications and discuss achieved improvements and advantages of our modelling, such as the importance and the impact of time on the overall CVSS score calculation.
    • A multicriteria approach to evaluating habitat change in urban areas: an example from the Black Country (UK)

      Young, Christopher; Jarvis, Peter (Ashurst: WIT Press, 2003)
      THE BOOK: The pressure on land resources in densely populated industrialized countries is now immense. Multifunctional management is therefore a prerequisite for the sustainable use of landscapes, and the only general strategy that may address the problems created by constantly growing demands on resources arising from production, residence, dumping of waste, habitat, ecosystem services, and recreation. This volume focuses on the discussion and research recommendations relating to three different aspects of future landscape research concerning planning and management: Monitoring Multifunctional Landscapes; Biodiversity Versus Landscape Diversity in Multifunctional Landscapes; and Complexity of Landscape Management. (WIT Press)
    • A new and intuitive test for zero modification

      Wilson, Paul; Einbeck, Jochen; School of Mathematics and Computer Science, University of Wolverhampton, United Kingdom.; Department of Mathematical Sciences, Durham University, United Kingdom. (Sage, 2018-04-05)
      While there do exist several statistical tests for detecting zero modification in count data regression models, these rely on asymptotical results and do not transparently distinguish between zero inflation and zero deflation. In this manuscript, a novel non-asymptotic test is introduced which makes direct use of the fact that the distribution of the number of zeros under the null hypothesis of no zero modification can be described by a Poisson-binomial distribution. The computation of critical values from this distribution requires estimation of the mean parameter under the null hypothesis, for which a hybrid estimator involving a zero-truncated mean estimator is proposed. Power and nominal level attainment rates of the new test are studied, which turn out to be very competitive to those of the likelihood ratio test. Illustrative data examples are provided.
    • A new measure of molecular attractions between nanoparticles near kT adhesion energy

      Kendall, Kevin; Dhir, Aman; Du, Shangfeng (IOP Publishing, 2009-03)
      The weak molecular attractions of nanoparticles are important because they drive self-assembly mechanisms, allow processing in dispersions e.g. of pigments, catalysts or device structures, influence disease through the attraction of viruses to cells and also cause potential toxic effects through nanoparticle interference with biomolecules and organs. The problem is to understand these small forces which pull nanoparticles into intimate contact; forces which are comparable with 3kT/2z the thermal impact force experienced by an average Brownian particle hitting a linear repulsive potential of range z. Here we describe a new method for measuring the atomic attractions of nanoparticles based on the observation of aggregates produced by these small forces. The method is based on the tracking of individual monosize nanoparticles whose diameter can be calculated from the Stokes–Einstein analysis of the tracks in aqueous suspensions. Then the doublet aggregates are distinguished because they move slower and are also very much brighter than the dispersed nanoparticles. By finding the ratio of doublets to singlets, the adhesive energy between the particles can be calculated from known statistical thermodynamic theory using assumptions about the shape of the interaction potential. In this way, very small adhesion energies of 2kT have been measured, smaller than those seen previously by atomic force microscopy (AFM) and scanning tunneling microscopy (STM).
    • A new species of death adder (Acanthophis: Serpentes: Elapidae) from north-western Australia

      Maddock, Simon T; Ellis, Ryan J; Doughty, Paul; Smith, Lawrence A; Wüster, Wolfgang (Magnolia Press, 2015-08-28)
      Australian death adders (genus Acanthophis) are highly venomous snakes with conservative morphology and sit-and-wait predatory habits, with only moderate taxonomic diversity that nevertheless remains incompletely understood. Analyses of mitochondrial and nuclear gene sequences and morphological characteristics of death adders in northern Australia reveal the existence of a new species from the Kimberley region of Western Australia and the Northern Territory, which we describe as Acanthophis cryptamydros sp. nov. Although populations from the Kimberley were previously considered conspecific with Northern Territory death adders of the A. rugosus complex, our mtDNA analysis indicates that its closest relatives are desert death adders, A. pyrrhus. We found that A. cryptamydros sp. nov. is distinct in both mtDNA and nDNA analysis, and possesses multiple morphological characteristics that allow it to be distinguished from all other Acanthophis species. This study further supports the Kimberley region as an area with high endemic biodiversity.
    • A New Species of New Guinea Worm-Eating Snake, Genus Toxicocalamus (Serpentes: Elapidae), From the Star Mountains of Western Province, Papua New Guinea, With a Revised Dichotomous Key to the Genus

      O’Shea, Mark; Parker, Fred; Kaiser, Hinrich (2015-07)
      We describe a new species of New Guinea vermivorous snake (Toxicocalamus) from a single specimen collected at Wangbin in the Star Mountains, Western Province, Papua New Guinea. The new species is the largest known member of the genus and can be differentiated from all other Toxicocalamus by a combination of the following characters: large size (total length of the holotype 1,200 mm), dorsal head scutes in the typical ‘‘colubrid-elapid dorsal nine-scute arrangement’’; separate, single preocular and paired postoculars; single anterior temporal and single or paired posterior temporals; six supralabials, with third and fourth supralabial contacting the orbit; dorsal scales in 15–15–15 rows; 203 ventral scales, 29 subcaudal scales; and a divided anal plate. Its erstwhile status, misidentified as Micropechis ikaheka in the collection of the Museum of Comparative Zoology, demonstrates the need for detailed examination of existing collections and is indicative of hidden diversity yet to be identified, not only in the field but also on the shelves of museum collections. We also provide a revised key to the genus Toxicocalamus.
    • A new species of small and highly abbreviated caecilian (Gymnophiona: Indotyphlidae) from the Seychelles island of Praslin, and a recharacterization of Hypogeophis brevis Boulenger, 1911

      A new species of indotyphlid caecilian amphibian, Hypogeophis pti sp. nov., is described based on a series of specimens from the Seychelles island of Praslin. The type series was collected in 2013 and 2014, and a referred specimen previously identified as H. brevis Boulenger, 1911 was collected from an unspecified Seychelles locality in 1957. The new species most closely resembles the Seychelles endemic Hypogeophis brevis in being short (maximum known total length in life ca. 120 mm) and long snouted, but differs by having a less anteriorly positioned tentacular aperture and fewer primary annuli and vertebrae. In having only 67–69 vertebrae, H. pti sp. nov. is the most abbreviated extant species of caecilian reported to date. 
    • A new species of the Cyrtodactylus (Geckoella) collegalensis (Beddome, 1870) complex (Squamata: Gekkonidae) from Western India

      A new species of Cyrtodactylus (Geckoella) from the C. collegalensis complex is described based on a series of specimens from western and central India. Morphological and molecular data support the distinctiveness of the new form, which can be diagnosed from other Cyrtodactylus (including other Geckoella) species by its small body size (snout to vent length to 56 mm), the absence of precloacal and femoral pores, no enlarged preanal or femoral scales, and a dorsal scalation consisting wholly of small, granular scales. The new species is most closely related to C. collegalensis, C. speciosus and C. yakhuna, from which it differs by the presence of a patch of enlarged roughly hexagonal scales on the canthus rostralis and beneath the angle of jaw, its relatively long limbs and narrow body, and a dorsal colour pattern of 4–6 pairs of dark spots.
    • A Novel Birefrigent Photonic Crystal Fiber Surface Plasmon Resonance Biosensor

      Otupiri, R.; Akowuah, E. K.; Haxha, S.; Ademgil, H.; AbdelMalek, F.; Aggoun, A. (IEEE, 2014-08)
      A numerical analysis of a novel birefringent photonic crystal fiber (PCF) biosensor constructed on the surface plasmon resonance (SPR) model is presented in this paper. This biosensor configuration utilizes circular air holes to introduce birefringence into the structure. This PCF biosensor model shows promise in the area of multiple detection using HEx 11 and HEy 11 modes to sense more than one analyte. A numerical study of the biosensor is performed in two interrogation modes: amplitude and wavelength. Sensor resolution values with spectral interrogation yielded 5 10 5 RIU (refractive index units) for HEx 11 modes and 6 10 5 RIU for HEy 11 modes, whereas 3 10 5 RIU for HEx 11 modes and 4 10 5 RIU for HEy 11 modes are demonstrated for the amplitude interrogation.
    • A novel mechanism for the anti-cancer activity of aspirin and salicylates

      Bashir, Asma'u I.J.; Kankipati, Chandras S.; Jones, Sarah; Newman, Robert M.; Safrany, Stephen T.; Perry, Christopher J.; Nicholl, Iain D. (Spandidos Publications Ltd, 2019-01-29)
      Epidemiological studies indicate that long-term aspirin usage reduces the incidence of colorectal cancer (CRC) and may protect against other non-CRC associated adenocarcinomas, including oesophageal cancer. A number of hypotheses have been proposed with respect to the molecular action of aspirin and other non‑steroidal anti‑inflammatory drugs in cancer development. The mechanism by which aspirin exhibits toxicity to CRC has been previously investigated by synthesising novel analogues and derivatives of aspirin in an effort to identify functionally significant moieties. Herein, an early effect of aspirin and aspirin-like analogues against the SW480 CRC cell line was investigated, with a particular focus on critical molecules in the epidermal growth factor (EGF) pathway. The present authors proposed that aspirin, diaspirin and analogues, and diflunisal (a salicylic acid derivative) may rapidly perturb EGF and EGF receptor (EGFR) internalisation. Upon longer incubations, the diaspirins and thioaspirins may inhibit EGFR phosphorylation at Tyr1045 and Tyr1173. It was additionally demonstrated, using a qualitative approach, that EGF internalisation in the SW480 cell line may be directed to endosomes by fumaryldiaspirin using early endosome antigen 1 as an early endosomal marker and that EGF internalisation may also be perturbed in oesophageal cell lines, suggestive of an effect not only restricted to CRC cells. Taken together and in light of our previous findings that the aspirin-like analogues can affect cyclin D1 expression and nuclear factor-κB localisation, it was hypothesized that aspirin and aspirin analogues significantly and swiftly perturb the EGFR axis and that the protective activity of aspirin may in part be explained by perturbed EGFR internalisation and activation. These findings may also have implications in understanding the inhibitory effect of aspirin and salicylates on wound healing, given the critical role of EGF in the response to tissue trauma.
    • A Novel Method for Cleaning Reaction Vessels.

      Cox, Jeffrey J.; Gibbons, M. N. N.; Hudson, I. D.; Williams, Craig D. (NISCAIR, 2002)
      The objective of zeolite synthesis is the production of pure phase material and a study by Lowe et al. showed that small and possibly significant amounts of template remaining in supposedly clean vessels could influence the crystallisation of subsequent gels. Two cleaning methods are widely used to clean the synthesis reaction vessels i.e. hydrofluoric acid or a solution of sodium hydroxide at reaction temperature, but their efficacy has not been tested. Zeolite omega was synthesized with both organic and inorganic templates and, following synthesis, the reaction vessels were cleaned by a novel method, described here, using hydrofluoric acid, crown ethers, and ultrapure water. This new method was compared to the standard methods by using a ‘scavenging gel’ to test the cleanliness of the vessels. The ‘scavenging gel’ produced some crystalline material when used following conventional cleaning whereas, when the vessels were cleaned using the method described here, the gel failed to crystallise. Conductivity measurements have proved a reliable index to the cleanliness of the reaction vessels.
    • A review of factors affecting electrostatic charging of pharmaceuticals and adhesive mixtures for inhalation

      Kaialy, Waseem (Elsevier, 2016-02-02)
      Pharmaceutical powders are typically insulators consisting of relatively small particles and thus they usually exhibit significant electrostatic charging behaviours. In the inhalation field, the measurement of electrostatic charge is an imperative stage during pharmaceutical formulation development. The electrostatic charge is affected by the interplay of many factors. This article reviews the factors affecting the electrostatic charging of pharmaceutical powders with a focus on dry powder inhalations. The influences of particle resistivity, size distribution, shape distribution, surface roughness, polymorphic form and hygroscopicity, as well as the effects of moisture uptake, environmental conditions, pharmaceutical processing (i.e., milling, sieving, spray drying and blending), and storage on the electrostatic charge behaviours of pharmaceuticals, with focus on inhalation powders, were reviewed. The influence of electrostatic charge on the performance of dry powder inhaler formulations in terms of drug content homogeneity, the passage of drug through the inhaler device, drug-carrier adhesion/detachment, and drug deposition on the respiratory airways were discussed. The understanding gained is crucial to improving the safety, quality, and efficiency of the pharmaceutical inhalation products.
    • A review of photovoltaic module technologies for increased performance in tropical climate

      Ogbomo, Osarumen O.; Amalu, Emeka H.; Ekere, N.N.; Olagbegi, P.O. (Elsevier, 2016-11-23)
      The global adoption and use of photovoltaic modules (PVMs) as the main source of energy is the key to realising the UN Millennium Development Goals on Green Energy. The technology – projected to contribute about 20% of world energy supply by 2050, over 60% by 2100 and leading to 50% reduction in global CO2 emissions – is threatened by its poor performance in tropical climate. Such performance discourages its regional acceptance. The magnitude of crucial module performance influencing factors (cell temperature, wind speed and relative humidity) reach critical values of 90 °C, 0.2 m/s and 85%, respectively in tropical climates which negatively impact module performance indices which include power output (PO), power conversion efficiency (PCE) and energy payback time (EPBT). This investigation reviews PVM technologies which include cell, contact and interconnection technologies. It identifies critical technology route(s) with potential to increase operational reliability of PVMs in the tropics when adopted. The cell performance is measured by PO, PCE and EPBT while contacts and interconnections performance is measured by the degree of recombination, shading losses and also the rate of thermo-mechanical degradation. It is found that the mono-crystalline cell has the best PCE of 25% while the Cadmium Telluride (CdTe) cell has the lowest EPBT of 8-months. Results show that the poly-crystalline cell has the largest market share amounting to 54%. The CdTe cell exhibits 0% drop in PCE at high-temperatures and low irradiance operations – demonstrating least affected PO by the conditions. Further results establish that back contacts and back-to-back interconnection technologies produce the least recombination losses and demonstrate absence of shading in addition to possessing longest interconnection fatigue life. Based on these findings, the authors propose a PVM comprising CdTe cell, back contacts and back-to-back interconnection technologies as the technology with latent capacity to produce improved performance in tropical climates.
    • A review of potential techniques for the creation of intelligent agents in virtual environments

      Davies, N.P.; Mehdi, Qasim; Gough, Norman; Anderson, Don; Jacobi, Dennis; von Borries, Vance (University of Wolverhampton, School of Computing and Information Technology, 2004)
      This paper presents a review of potential architectures and tools for the production of Virtual Environments with Integrated Intelligent Characters. Initial research was carried out into the production of a real-time system for the creation of graphically realistic scenes for crime scene reconstruction in Davies et al (2004). The system was capable of rendering scenes produced via a graphical interface, and characters with pregenerated animation sequences could be placed and oriented in the scenes to act out crime events. It is proposed that these characters would be more beneficial if they were endowed with intelligent qualities so they could act in an autonomous manner when presented with a scenario. It is anticipated that this would produce a diverse set of actions and resulting scene disturbance which would be of benefit to forensic crime investigation students, who could theories about the events performed in the scene, and evaluate their responses against the actual events.