Search results for: Brett Stevens

Authors: Daniel Panario, Daniel Santana de Freitas, Brett Stevens

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Almost Perfect Nonlinear (APN) permutations with optimal resistance against differential cryptanalysis can be found in several domains. The permutation used in the standard for symmetric cryptography (the AES), for example, is based on a special kind of inversion in GF(28). Although very close to APN (2-uniform), this permutation still contains one number 4 in its differential spectrum, which means that, rigorously, it must be classified as 4-uniform. This fact motivates the search for fully APN permutations in other domains of definition. The extremely high complexity associated to this kind of problem precludes an exhaustive search for an APN permutation with 256 elements to be performed without the support of a suitable mathematical structure. On the other hand, in principle, there is nothing to indicate which mathematically structured domains can effectively help the search, and it is necessary to test several domains. In this work, the search for APN permutations in rings ℤ2×ℤ2k is investigated. After a full, exhaustive search with k=2 and k=3, all possible APN permutations in those rings were recorded, together with their differential profiles. Some very promising heuristics in these cases were collected so that, when used as a basis to prune backtracking for the same search in ℤ2×ℤ8 (search space with size 16! ≅244), just a few tenths of a second were enough to produce an APN permutation in a single CPU. Those heuristics were empirically extrapolated so that they could be applied to a backtracking search for APNs over ℤ2×ℤ16 (search space with size 32! ≅2117). The best permutations found in this search were further refined through Simulated Annealing, with a definition of neighbors suitable to this domain. The best result produced with this scheme was a 3-uniform permutation over ℤ2×ℤ16 with only 24 values equal to 3 in the differential spectrum (all the other 968 values were less than or equal 2, as it should be the case for an APN permutation). Although far from being fully APN, this result is technically better than a 4-uniform permutation and demanded only a few seconds in a single CPU. This is a strong indication that the use of mathematically structured domains, like the rings described in this work, together with heuristics based on smaller cases, can lead to dramatic cuts in the computational resources involved in the complexity of the search for APN permutations in extremely large domains.

Keywords: APN permutations, heuristic searches, symmetric cryptography, S-box design

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Authors: Natida Thongsima, Patompong Satapornpong

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Introduction: Lamotrigine is widely used in the treatment of epilepsy and bipolar disorder. However, lamotrigine leads to adverse drug reactions (ADRs) consist of severe cutaneous adverse reactions (SCARs) include Stevens–Johnson syndrome (SJS), toxic epidermal necrolysis (TEN) and drug rash with eosinophilia and systemic symptoms (DRESS). Moreover, lamotrigine-induced SCARs are usually manifested between 2 and 8 weeks after treatment initiation. According to a previous study, the association between HLA-B*15:02 and lamotrigine-induced cutaneous adverse drug reactions in the Thai population (odds ratio 4.89; 95% CI 1.28–18.66; p-value = 0.014) was found. Therefore, the distribution of pharmacogenetics markers a major role in predicting the culprit drugs for SCARs in many populations. Objective: In this study, we want to investigate the prevalence of HLA-B allele, which correlates with lamotrigine-induced SCARs in the healthy Thai population. Materials and Methods: We enrolled 350 healthy Thai individuals and were approved by the ethics committee of Rangsit University. HLA-B alleles were genotyped by the Lifecodes HLA SSO typing kits (Immucor, West Avenue, Stamford, USA). Results: The results presented HLA-B allele frequency in healthy Thai population were 14.71% (HLA-B*46:01), 8.57% (HLA-B*15:02), 6.71% (HLA-B*40:01), 5.86% (HLA-B*13:01), 5.71% (HLA-B*58:01), 5.14% (HLA-B*38:02), 4.86% (HLA-B*18:01), 4.86% (HLA-B*51:01), 3.86% (HLA-B*44:03) and 2.71% (HLA-B*07:05). Especially, HLA-B*15:02 allele was the high frequency in the Thais (8.57%), Han Chinese (7.30%), Vietnamese (13.50%), Malaysian (6.06%) and Indonesian (11.60%). Nevertheless, this allele was much lower in other populations, namely, Africans, Caucasians, and Japanese. Conclusions: Although the sample size of the healthy Thai population in this research was limited, there were found the frequency of the HLA-B*15:02 allele could predispose them toward to lamotrigine-induced SCARs in Thailand.

Keywords: lamotrigine, cutaneous adverse drug reactions, HLA-B, Thai population

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Authors: Awei Bainivalu, Joachim Larsen, Logesh Panneerselvan, Toby Mills, Brett Neilan, Megharaj Mallavarapu

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World War II (WWII) shipwrecks harbour up to 20 million tonnes of oil. More than 3000 wrecks are in the Pacific Ocean; 300 are oil tankers. Compared to other oil removal methods, bioremediation is environmentally friendly and cost-effective. Oil's microbial community and hydrocarbon properties from the Pacific WWII wrecks were identified. Dominant phyla are Proteobacteria, Actinobacteria, and Firmicutes. Native marine bacteria oil-degraders were isolated for bioremediation. Petroleum degradation data from the bacterial consortium will be analyzed over the next three months.

Keywords: oil bioremediation, marine bacteria, WWII shipwrecks, pacific

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Authors: Masami Usui

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Kazuo Ishiguro’s The Remains of the Day (1989) underlines another holocaust, an imprisonment of human life, dignity, and self in the globalizing sphere of the twentieth century. The Remains of the Day delineates the invisible and cruel space of “lost and found” in the postcolonial and post-imperial discourse of this century, that is, the Holocaust. The context of the concentration camp or wartime imprisonment such as Auschwitz is transplanted into the public sphere of modern England, Darlington Hall. The voice is retrieved and expressed by the young journalist and heir of Darlington Hall, Mr. David Cardinal. The new media of journalism is an intruder at Darlington Hall and plays a role in revealing the wrongly-input ideology. “Lost and Found” consists of the private and public retrieved voices. Stevens’ journey in 1956 is a return to the past, especially the period between 1935 and 1936. Lost time is retrieved on his journey; yet lost life cannot be revived entirely in his remains of life. The supreme days of Darlington Hall are the terrifying days caused by the Nazis. Fascism, terrorism, and militarism destroyed the wholesomeness of the globe. Into blind Stevens, both Miss Kenton and Mr. Cardinal bring out the common issue, that is, the political conflicts caused by Nazis. Miss Kenton expresses her own ideas against anti-Semitism regarding the Jewish maids in the crucial time when Sir Oswald Mosley’s Blackshirts organization attacked the Anglo Jews between 1935 and 1936. Miss Kenton’s half-muted statement is reinforced and assured by Cardinal in his mention of the 1934 Olympic Rally threatened by Mosley’s Blackshirts. Cardinal’s invasion of Darlington Hall embodies the increasing tension of international politics related to World War II. Darlington Hall accommodates the crucial political issue that definitely influences the fate of the house, its residents, and the nation itself and that is retrieved in the newly progressive and established media.

Keywords: modern English literature, culture studies, communication, history

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Authors: Robert K. Hillyard, Jonathan Thomas, Brett A. Story

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Compressed Stabilized Earth Blocks (CSEB) are masonry units that combine soil, sand, stabilizer, and water under pressure to form an earth block. These CSEB’s offer a cost-effective building solution for remote construction, using local resources and labor to minimize transportation and material costs. However, CSEB’s, and earthen construction generally have not been widely adopted as standardized construction materials. One shortcoming is the difficulty in standardizing strength values of CSEB units and systems due to the inherent variations in mix design, including production compression. This research presents findings on compressive strengths of full-scale CSEB’s from 60 different mix designs as a function of the amount of cement, sand, soil, and water added to the mixture. The full-scale results are compared with CSEB cylinder cores.

Keywords: CSEB, compressive strength, earth construction, mix design

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Authors: Doreen Orishaba, Paul Isaac Musasizi, Richard Madanda, Sandy Stevens Tickodri-Togboa

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The world of academia tends to be a very insular place. Consequently, scholars who successfully completed their undergraduate and graduate studies are unpleasantly surprised at how challenging the transition to corporate life can get. This is a global trend even as the students who juggle work with attending some of the most demanding and best graduate programs may not easily adjust to and confirm to the professionalism required for corporate management of the industry. This paper explores the trends in the transition of Kiira EV Project from a predominantly student team to a professional team of a national pride program through mentorship and apprenticeship. The core disciplines within the Kiira EV Project include Electrical and Electronics Engineering, Mechanical Engineering, and Industrial Design.

Keywords: mentorship, apprenticeship, professional, development

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Authors: Cate MacMillan, Nicholas J. Stevens, Johanna Rosier, Steven Boyd

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Choosing where to live is an important decision for anybody, however, this decision is more complex if you are an adult with intellectual disability. Our research asked adults with intellectual disability, parents and carers and disability, housing and built environment decision makers what they considered important in deciding where to live. If medical advances continue to improve the longevity of adults with intellectual disability, many of these adults will outlive their parents. With appropriate community support, and in appropriately designed neighbourhoods, many will be able to live independently. Our research suggests that the key to achieving independent living as an adult with intellectual disability is not so much about the house but the type of neighbourhood and its design. This paper presents the results of interviews and details a practical approach which will better inform urban development decision-makers in establishing safe, inclusive and accessible neighbourhood design.

Keywords: inclusion, independent living, intellectual disability, neighbourhoods, systems thinking, urban design and planning

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Authors: Julia B. Kischkat, Charlie D. Waters

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This research aims to understand the factors that may affect the survival and productivity of Pacific salmonids through two components. The first component is lab-based and aims to improve high-performance liquid chromatography to better quantify vitamin deficiencies such as thiamine. The lab work is conducted at the National Oceanic and Atmospheric Administration (NOAA) Ted Stevens Marine Research Institute in Juneau, Alaska. Deficiencies in thiamine have been shown to reduce the survival of salmonids at early life stages. The second component involves the analysis of a 22-year data set of migration timing of juvenile Coho Salmon, Dolly Varden, Steelhead, and returning adult Steelhead at Little Port Walter, Alaska. The statistical analysis quantifies their migration fluctuations and whether they correlate to various environmental conditions such as temperature, salinity, and precipitation.

Keywords: climate change, smolt timing, phenology, migration timing, salmon, time series analysis, ecology, chemistry, fisheries science

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Authors: Richard Madanda, Paul Isaac Musasizi, Sandy Stevens Tickodri-Togboa, Doreen Orishaba, Victor Tumwine

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New vehicle concepts targeting specific geographical markets are designed to satisfy a unique set of road and load requirements. The KIIRA-EV SMACK (KES) hybrid vehicle is designed in Uganda for the East African market. The engine and generator added to the KES electric power train serve both as the range extender and the power assist. In this paper, the design consideration taken to achieve the proper management of the on-board power from the batteries and engine-generator based on the specific drive cycle are presented. To harness the fuel- efficiency benefits of the power train, a specific control philosophy operating the engine and generator at the most efficient speed- torque and speed-power regions is presented. By using a suitable model developed in MATLAB using Simulink and Stateflow, preliminary results show that the steady-state response of the vehicle for a particular hypothetical drive cycle mimicking the expected drive conditions in the city and highway traffic is sufficient.

Keywords: control strategy, drive cycle, hybrid vehicle, simulation

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Authors: Nan Stevens

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Photo-voice is a participatory method through which participants identify and represent their lived experiences and contexts through the use of photo imagery. Photo-voice is a qualitative research method that explores individuals’ lived experiences. This method is known as a creative art form to help researchers listen to the 'voice' of a certain population. A teacher educator at Thompson Rivers University, responsible for preparing new teachers for the demands of the profession in an ever-changing demographic, utilized the Photo-voice method to enable a self-study of emerging teachers’ readiness for the inclusive classroom. Coding analysis was applied to 96 Photo-voice portfolios, which were created over two years with the Inclusive Education course work, in a Bachelor of Education program (Elementary). Coding utilized students’ written associations to their visual images, anecdotes attached to visual metaphors, and personal narratives that illustrated the professional development process in which they were engaged. Thematic findings include: 1) becoming an inclusive educator is a process; 2) one must be open to identifying and exploring their fear and biases, and 3) an attitudinal shift enables relevant skill acquisition and readiness for working with diverse student needs.

Keywords: teacher education, inclusive education, professional development, Photo-voice

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Authors: R. Stevens, W.L. Bryden

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The objective of this study was to determine the efficacy of zeolite in preventing the adverse effects of aflatoxin B1 (AFB1) in broilers. A total of 540 one-day-old Ross chicks were randomly divided into nine treatments, with four replicate pens per treatment and 15 chicks per pen. The treatments included 3 Levels of AFB1 (0,1and 2 mg/kg diet) and 3 levels of zeolite (0, 1.5 and 3 %) in a 3 ×3 factorial arrangement. The experimental treatments commenced on d 7 post-hatch. A starter diet was provided from d 1 to 14, a grower diet from d 15 to 28 and a finisher diet from d 29 to d 49. Diets were based on corn and soybeans and formulated to meet the bird's requirements. The evaluated parameters were as follows: Bodyweight, daily gain, feed intake (FI), feed conversion (FC), relative weights of organs (carcass, liver, heart and abdominal fat) and clinical biochemistry parameters: alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Bodyweight, daily gain and FC were significantly (P<0.05) impaired by aflatoxin. Relative weights of the liver and heart were also affected. The addition of zeolite (1.5 and 3 %) to the contaminated diets ameliorated the effects of aflatoxin, especially at the higher level of inclusion. These data demonstrate that this specific sorbent (zeolite) can protect against the toxicity of AFB1in young broiler chicks.

Keywords: aflatoxin, broiler, toxicity, zeolite

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Authors: Jaomai Tungsiripat, Patompong Satapornpong

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Allopurinol have been used to treat diseases that relating with the reduction of uric acid and be a treatment preventing the severity of, including gout, chronic kidney disease, chronic heart failure, and diabetes mellitus (type 2). However, allopurinol metabolites can cause a severe cutaneous adverse reaction (SCARs) consist of Drug Rash with Eosinophilia and Systemic Symptoms (DRESS) and Stevens-Johnson Syndrome(SJS)/Toxic Epidermal Necrolysis (TEN). Previous studies, we found only HLA-B*58:01 allele has a strongly association with allopurinol-induced SCARs in many populations: Han Chinese [P value = 4.7 x 10−24], European [P value <10−6], and Thai [P value <0.001].However, there was no update the frequency of HLA-B alleles and pharmacogenetics markers distribution in healthy Thais and support for screening before the initiation of treatment. The aim of this study was to investigate the prevalence of HLA-B*58:01 allele associated with allopurinol-induced SCARs in healthy Thai population. A retrospective study of 260 individual healthy subjects who living in Thailand. HLA-B were genotyped using sequence-specific oligonucleotides (PCR-SSOs).In this study, we identified the prevalence of HLA-B alleles consist ofHLA-B*46:01 (12.69%), HLA-B*15:02 (8.85%), HLA-B*13:01 (6.35%), HLA-B*40:01 (6.35%), HLA-B*38:02 (5.00%), HLA-B*51:01 (5.00%), HLA-B*58:01 (4.81%), HLA-B*44:03 (4.62%), HLA-B*18:01 (3.85%) and HLA-B*15:25 (3.08%). Therefore, the distribution of HLA-B*58:01 will support the clinical implementation and screening usage of allopurinol in Thai population.

Keywords: allopurinol, HLA-B*58: 01, Thai population, SCARs

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Authors: Watchawin Ekphinitphithaya, Patompong Satapornpong

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Introduction: Carbamazepine (CBZ) is one of the most prescribed antiepileptic drugs (AEDs) by neurologists and non-neurologist worldwide. CBZ is usually prescribed along with other drugs, leading to the possibility of severe cutaneous adverse drug reactions (SCARs). The HLA-B*15:02 is strongly associated with CBZ-induced Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS–TEN) in the Han Chinese and other Asian populations but not in European populations, while HLA-A*31:01 allele has been reported to be associated with CBZ-induced SCARs in European population and Japanese. Objective: The aim of this study is to investigate the distribution of pharmacogenetics HLA-A*31:01 marker in a healthy Thai population associated with Carbamazepine-induced SCARs. Materials and Methods: Prospective study, 350 unrelated healthy Thais were recruited in this study. Human leukocyte antigen-A alleles were genotyped using PCR-sequence specific oligonucleotides (PCR-SSOs). Results: The frequency of HLA-A alleles were HLA-A*11:01 (190 alleles, 27.14%), HLA-A*24:02 (82 alleles, 11.71%), HLA-A*02:03 (80 alleles, 11.43%), HLA-A*33:03 (76 alleles, 10.86%), HLA-A*02:07 (58 alleles, 8.29%), HLA-A*02:01 (35 alleles, 5.00%), HLA-A*24:07 (29 alleles, 4.14%), HLA-A*02:06 – HLA-A*30:01 (15 alleles, 2.14%), and HLA-A*01:01 (14 alleles, 2.00%). Particularly, the number of HLA-A*31:01 alleles was 6 of 700 (0.86%) in the healthy Thai population. Many research presented varying distributions of HLA-A*31:01 in Asians, including 2% of Han Chinese, 9% of Japanese and 5% of Koreans. In addition, this allele was found approximately 2-5% in the Caucasian population. Conclusions: Thus, the pharmacogenetics database is vital to support in many populations, especially in Thais, for screening HLA-A*31:01 allele to avoid CBZ-induced SCARs before initiating treatments in each population.

Keywords: Carbamazepine, HLA-A*31:01, Thai population, pharmacogenetics

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Authors: Laura Gantley, Vanessa M. Conn, Stuart Webb, Kirsty Kirk, Marta Gabryelska, Duncan Holds, Brett W. Stringer, Simon J. Conn

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Trinucleotide repeat disorders comprise ~20 severe, inherited human neuromuscular and neurodegenerative disorders, which are a result of an abnormal expansion of repetitive sequences in the DNA. The most common of these, Huntington’s disease, results from the expansion of the CAG repeat region in exon 1 of the HTT gene via an unknown mechanism. Non-coding RNAs have been implicated in the initiation and progression of many diseases; thus, we focus on one circular RNA (circRNA) molecule arising from non-canonical splicing (back splicing) of HTT pre-mRNA. This circRNA and its mouse orthologue were transgenically overexpressed in human cells (SHSY-5Y and HEK293T) and mouse cells (Mb1), respectively. High-content imaging and flow cytometry demonstrated the overexpression of this circRNA reduces cell proliferation, reduces nuclear size independent of cellular size, and alters cell cycle progression. Analysis of protein by western blot and immunofluorescence demonstrated no change to HTT protein levels but altered nuclear-cytoplasmic distribution without impacting the expansion of the HTT repeat region. As these phenotypic and genotypic changes are found in Huntington’s disease patients, these results may suggest that this circRNA may play a functional role in the progression of Huntington’s disease.

Keywords: cell biology, circular RNAs, Huntington’s disease, molecular biology, neurodegenerative disorders

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Authors: Ryan Stevens, Wayne L. Bryden

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This study focused on the effects of ginger and a zeolite (toxin binder) in reducing the toxic effects of aflatoxin B1 (AFB1) in broiler chickens 7 to 49 days of age. The chicks were maintained normally until experimental diets were introduced on day 7 post-hatching. Nine hundred and thirty six, 7-d-old broiler chickens were randomly assigned to 18 treatment groups; each group had four replicates, each with 13 chickens. The experimental groups or diets had factorial combinations of the following; AFB1 0, 1 and 2 mg/kg diet, ginger 0 and 5g/kg diet, and zeolite 0, 15 and 30 g/kg diet. Diets were based on corn and soybean meal and a starter diet was fed from 1 to 14 days, a grower diet from15 to 28 days and a finisher diet was provided from day 29 until the end of the experiment. Both dietary levels of AFB1 decreased (P<0.05) body weight and feed conversion, and increased relative liver weights. Independent dietary inclusion of ginger or zeolite restored chick performance when diets contained 1mg/kg but not at 2mg/kg. Supplementation of zeolite together with ginger improved performance of birds fed contaminated diets. Interestingly, adding ginger to the control diet that was not contaminated with AFB1 improved (P<0.05) performance. Our results suggest that toxin binders and ginger can provide protection against the negative effects of AFB1 on performance of broiler chicks.

Keywords: aflatoxin, broiler, ginger, zeolite

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Authors: Florian Monetti, Brett Beamsley, Peter McComb, Simon Weppe

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Land reclamation from the ocean has considerably increased over past decades to support worldwide rapid urban growth. Reshaping the coastline, however, inevitably affects coastal systems. One of the main challenges for coastal oceanographers is to predict the physical and morphological responses for nearshore systems to man-made changes over multiple time-scales. Fully-coupled numerical models are powerful tools for simulating the wide range of interactions between flow field and bedform morphology. Restricted and inconsistent measurements, combined with limited computational resources, typically make this exercise complex and uncertain. In the present study, we investigate the impact of proposed land reclamation within a wave-dominated bay in New Zealand. For this purpose, we first calibrated our morphological model based on the long-term evolution of the bay resulting from land reclamation carried out in the 1950s. This included the application of sedimentological spin-up and reduction techniques based on historical bathymetry datasets. The updated bathymetry, including the proposed modifications of the bay, was then used to predict the effect of the proposed land reclamation on the wave climate and morphology of the bay after one decade. We show that reshaping the bay induces a distinct symmetrical response of the shoreline which likely will modify the nearshore wave patterns and consequently recreational activities in the area.

Keywords: coastal waves, impact of land reclamation, long-term coastal evolution, morphodynamic modeling

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Authors: Michael Stevens

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David Hunter, a musicologist, has suggested that both Beethoven and Handel had chronic lead poisoning from the wine that they drank. These two eminent musical composers had some striking similarities. Beethoven had alcohol dependency and preferred wine, to which lead had been added to improve the taste. Handel was obese due to an eating disorder that included drinking tainted wine after large meals. They both had paresthesia of their extremities that they interpreted as rheumatism. This is a common sensory symptom from chronic lead poisoning. Their differences are marked in that Beethoven was profoundly deaf by the end of his life, whereas Handel had remarkably good hearing. Handel had paresis of three fingers of his right hand, whereas Beethoven lacked any motor symptoms. Beethoven reported recurrent abdominal pain suggestive of lead colic, whereas it can only be inferred that this symptom was present in Handel. Lead poisoning is likely in Handel because his paralysis was consistent with radial nerve involvement in the dominant hand. In addition, it was cured by hot baths, which have been shown to reduce total body lead content by exchanging with iron and calcium ions in water. Although lead produces predominantly motor symptoms in classic or subacute lead poisoning, and sensory symptoms in chronic lead poisoning, lead poisoning causes a variety of symptoms that depending on duration and level of exposure, are extremely variable from person to person. It therefore seems likely that Handel had lead poisoning, but extremely likely that Beethoven did because of the confirmatory finding of high levels of lead deep in his skull bone, which is a good measure of total body burden.

Keywords: beethoven, handel, lead, poisoning

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Authors: Sriram Kashyap Prasad, Ionut Florescu

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This study models the intraday asset prices as driven by Markov process. This work identifies the latent states of the Hidden Markov model, using limit order book data (trades and quotes) to continuously estimate the states throughout the day. This work builds a trading strategy using estimated states to generate signals. The strategy utilizes current state to recalibrate buy/ sell levels and the transition between states to trigger stop-loss when adverse price movements occur. The proposed trading strategy is tested on the Stevens High Frequency Trading (SHIFT) platform. SHIFT is a highly realistic market simulator with functionalities for creating an artificial market simulation by deploying agents, trading strategies, distributing initial wealth, etc. In the implementation several assets on the NASDAQ exchange are used for testing. In comparison to a strategy with static buy/ sell levels, this study shows that the number of limit orders that get matched and executed can be increased. Executing limit orders earns rebates on NASDAQ. The system can capture jumps in the limit order book prices, provide dynamic buy/sell levels and trigger stop loss signals to improve the PnL (Profit and Loss) performance of the strategy.

Keywords: algorithmic trading, Hidden Markov model, high frequency trading, limit order book learning

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Authors: Hansraj Riteesh Bookun, Emily Maree Stevens, Jarryd Leigh Solomon, Anthony Chan

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Objective: This was a retrospective cross-sectional study evaluating the safety and efficacy of femoral endarterectomy using the eversion technique with transection as opposed to the conventional endarterectomy technique with either vein or synthetic patch arterioplasty. Methods: Between 2010 to mid 2017, 19 patients with mean age of 75.4 years, underwent eversion femoral endarterectomy with transection by a single surgeon. There were 13 males (68.4%), and the comorbid burden was as follows: ischaemic heart disease (53.3%), diabetes (43.8%), stage 4 kidney impairment (13.3%) and current or ex-smoking (73.3%). The indications were claudication (45.5%), rest pain (18.2%) and tissue loss (36.3%). Results: The technical success rate was 100%. One patient required a blood transfusion following bleeding from intraoperative losses. Two patients required blood transfusions from low post operative haemogloblin concentrations – one of them in the context of myelodysplastic syndrome. There were no unexpected returns to theatre. The mean length of stay was 11.5 days with two patients having inpatient stays of 36 and 50 days respectively due to the need for rehabilitation. There was one death unrelated to the operation. Conclusion: The eversion technique with transection is safe and effective with low complication rates and a normally expected length of stay. It poses the advantage of not requiring a synthetic patch. This technique features minimal extraneous dissection as there is no need to harvest vein for a patch. Additionally, future endovascular interventions can be performed by puncturing the native vessel. There is no change to the femoral bifurcation anatomy after this technique. We posit that this is a useful adjunct to the surgeon’s panoply of vascular surgical techniques.

Keywords: endarterectomy, eversion, femoral, vascular

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Authors: Nick Weir, Robert Stevens, Alan Hargreaves, Martin McGinnity, Chris Tinsley

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Hydrophobic materials have previously demonstrated the ability to elevate cell-cell interactions and promote the formation of neural networks whilst aligned nanofibers demonstrate the ability to induce extensive neurite outgrowth in an aligned manner. Hydrophobic materials typically elicit an immune response upon implantation and thus materials used for implantation are typically hydrophilic. Poly-L-lactic acid (PLLA) is a hydrophobic, non-immunogenic, FDA approved material that can be electrospun to form aligned nanofibers. Primary rat cortical neurons cultured for 10 days on aligned PLLA nanofibers formed 3D cell clusters, approximately 800 microns in diameter. Neurites that extended from these clusters were highly aligned due to the alignment of the nanofibers they were cultured upon and fasciculation was also evident. Plasma treatment of the PLLA nanofibers prior to seeding of cells significantly reduced the hydrophobicity and abolished the cluster formation and neurite fasciculation, whilst reducing the extent and directionality of neurite outgrowth; it is proposed that hydrophobicity induces the changes to cellular behaviors. Aligned PLLA nanofibers induced the formation of a structure that mimics the grey-white matter compartmentalization that is observed in vivo and thus represents a step forward in generating organoids or biomaterial-based implants. Upon implantation into the brain, the biomaterial architectures described here may provide a useful platform for both brain repair and brain remodeling initiatives.

Keywords: hydrophobicity, nanofibers, neurite fasciculation, neurite outgrowth, PLLA

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Authors: Stevens Phaphadi Mamorobela

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The Covid-19 pandemic has accelerated the use of social media in SMEs to stay abreast with information about the latest news and developments and to predict the future world of business. The national shutdown regulations for curbing the spread of the Covid-19 virus resulted in SMEs having to distribute large volumes of information through social media platforms to collaborate and conduct business remotely. How much of the information shared on social media is used by SMEs as significant knowledge for economic rent is yet to be known. This study aims to investigate the facilitating conditions that enable SMEs’ intention to use social media as a knowledge-sharing platform to create economic rent and to cope with the Covid-19 challenges. A qualitative research approach was applied where semi-structured interviews were conducted with 13 SME owners located in the Gauteng province in South Africa to identify and explain the facilitating conditions of SMEs towards their intention to use social media as a knowledge-sharing tool in the Covid-19 era. The study discovered that the national lockdown regulations towards curbing the spread of the Covid-19 pandemic had compelled SMEs to adopt digital technologies that enabled them to quickly transform their business processes to cope with the challenges of the pandemic. The facilitating conditions, like access to high bandwidth internet coverage in the Gauteng region, enable SMEs to have strong intentions to use social media to distribute content and to reach out to their target market. However, the content is shared informally using diverse social media platforms without any guidelines for transforming content into rent-yielding knowledge.

Keywords: facilitating conditions, knowledge sharing, social media, intention to use, SME

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Authors: Patompong Satapornpong, Therdpong Tempark, Pawinee Rerknimitr, Jettanong Klaewsongkram, Chonlaphat Sukasem

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Dapsone (4, 4’-diaminodiphenyl sulfone, DDS) is broadly used for the treatment of inflammatory diseases and infections such as; leprosy, Pneumocystis jiroveci pneumonia in patients with HIV infection, neutrophilic dermatoses, dermatitis herpetiformis and autoimmune bullous disease. The severe cutaneous adverse drug reactions (SCARs) including, Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN) and drug reaction with eosinophilia and systemic symptoms (DRESS) are rare but severe life-threatening adverse drug reactions. Dapsone is one of many culprit drugs induced SJS, TEN and DRESS. Notwithstanding, to our knowledge, there are no studies of the association of HLA class I alleles and dapsone-induced SCARs in non-leprosy Thai patients. This investigation was a prospective cohort study, which performed in a total of 45 non-leprosy patients. Fifteen patients of dapsone-induced SCARs were classified as following the RegiSCAR criteria, and 30 dapsone-tolerant controls were exposed to dapsone more than 6 months without any evidence of cutaneous reactions. The genotyping of HLA-A, -B and –C were performed using sequence-specific oligonucleotides (PCR-SSOs). The Ethics Committee of Ramathibodi hospital, Mahidol University, approved this study. Among all HLA class I alleles, HLA-A*24:07, HLA-B*13:01, HLA-B*15:02, HLA-C*03:04 and HLA-C*03:09 were significantly associated with dapsone-induced SCARs (OR = 10.55, 95% CI = 1.06 – 105.04, p = 0.0360; OR = 56.00, 95% CI = 8.27 – 379.22, p = 0.0001; OR = 7.00, 95% CI = 1.17 – 42.00, p = 0.0322; OR = 6.00, 95% CI = 1.24 – 29.07, p = 0.0425 and OR = 17.08, 95% CI = 0.82 – 355.45, p = 0.0321, respectively). Furthermore, HLA-B*13:01 allele had strong association with dapsone-induced SJS-TEN and DRESS when compared with dapsone-tolerant controls (OR = 42.00, 95% CI = 2.88 – 612.31, p = 0.0064 and OR = 63.00, 95% CI = 7.72 – 513.94 and p = 0.0001, respectively). Consequently, HLA-B*13:01 might serve as a pharmacogenetic marker for screening before initiating the therapy with dapsone for prevention of dapsone-induced SCARs.

Keywords: dapsone-induced SCARs, HLA-B*13:01, HLA class I alleles, severe cutaneous adverse reactions, Thai

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Authors: Gerardo Arias, Richard Wall, Jamie Stevens

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Lucilia bufonivora Moniez, is an obligate parasite of toads and frogs widely distributed in Europe. Its sister taxon Lucilia silvarum Meigen behaves mainly as a carrion breeder in Europe, however it has been reported as a facultative parasite of amphibians. These two closely related species are morphologically almost identical, which has led to misidentification, and in fact, it has been suggested that the amphibian myiasis cases by L. silvarum reported in Europe should be attributed to L. bufonivora. Both species remain poorly studied and their taxonomic relationships are still unclear. The identification of the larval specimens involved in amphibian myiasis with molecular tools and phylogenetic analysis of these two closely related species may resolve this problem. In this work seventeen unidentified larval specimens extracted from toad myiasis cases of the UK, the Netherlands and Switzerland were obtained, their COX1 (mtDNA) and EF1-α (Nuclear DNA) gene regions were amplified and then sequenced. The 17 larval samples were identified with both molecular markers as L. bufonivora. Phylogenetic analysis was carried out with 10 other blowfly species, including L. silvarum samples from the UK and USA. Bayesian Inference trees of COX1 and a combined-gene dataset suggested that L. silvarum and L. bufonivora are separate sister species. However, the nuclear gene EF1-α does not appear to resolve their relationships, suggesting that the rates of evolution of the mtDNA are much faster than those of the nuclear DNA. This work provides the molecular evidence for successful identification of L. bufonivora and a molecular analysis of the populations of this obligate parasite from different locations across Europe. The relationships with L. silvarum are discussed.

Keywords: calliphoridae, molecular evolution, myiasis, obligate parasitism

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Authors: Morlu Stevens, Bareki Batlokwa

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The use of treated wastewater is widely employed to compensate for the scarcity of safe and uncontaminated freshwater. However, the existence of toxic heavy metal ions in the wastewater pose a health hazard to animals and the environment, hence, the importance for an effective technique to tackle the challenge. A multi-templated ion imprinted sorbent (Fe,Ni,Cu-IIP) for the simultaneous removal of heavy metal ions from waste water was synthesised employing molecular imprinting technology (MIT) via thermal free radical bulk polymerization technique. Methacrylic acid (MAA) was employed as the functional monomer, and ethylene glycol dimethylacrylate (EGDMA) as cross-linking agent, azobisisobutyronitrile (AIBN) as the initiator, Fe, Ni, Cu ions as template ions, and 1,10-phenanthroline as the complexing agent. The template ions were exhaustively washed off the synthesized polymer by solvent extraction in several washing steps, while periodically increasing solvent (HCl) concentration from 1.0 M to 10.0 M. The physical and chemical properties of the sorbents were investigated using Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD) and Atomic Force Microscopy (AFM) were employed. Optimization of operational parameters such as time, pH and sorbent dosage to evaluate the effectiveness of sorbents were investigated and found to be 15 min, 7.5 and 666.7 mg/L respectively. Selectivity of ion-imprinted polymers and competitive sorption studies between the template and similar ions were carried out and showed good selectivity towards the targeted metal ion by removing 90% - 98% of the templated ions as compared to 58% - 62% of similar ions. The sorbents were further applied for the selective removal of Fe, Ni and Cu from real wastewater samples and recoveries of 92.14 ± 0.16% - 106.09 ± 0.17% and linearities of R2 = 0.9993 - R2 = 0.9997 were achieved.

Keywords: ion imprinting, ion imprinted polymers, heavy metals, wastewater

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Authors: Dina Tawfic, Robert Hassan

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The current chapter addresses Al-Azhar's strategy to counter extremism in tandem with reflecting on the ideology of the Islamic establishment itself. The topic is motivated by the fact that some of the Western governments have been relying on Al-Azhar to counter the ideology of Islamist radicalism and violent extremism, in particular during the rise of the Islamic State in Syria and Iraq (known as ISIS/ ISIL/ Daesh) in 2014/2015. In his visit to Egypt in June 2016, Brett McGurk, the then U.S. envoy for the global coalition to counter ISIS, commended Al-Azhar’s “intellectual and reforming role” in refuting the ideology of extremism. On the other hand, Egyptian liberal intellectuals, such as Farag Fouda (1945- 1992) and Nasr Hamed Abu Zeid (1943-2010), had always questioned the ideological capability of Al-Azhar to counter extremism, citing the rigidity and resistance of the Islamic establishment to carry out genuine reformation. This chapter aims to discuss the following research questions: what is the strategy of Al-Azhar to counter extremism? Does Al-Azhar have a solid strategy to combat online propaganda produced by violent extremist groups? Is it applicable to identify Al-Azhar ideological identity? and is it capable of countering extremism? To answer these questions, I conducted intensive interviews with seven senior scholars and officials at Al-Azhar and the Endowments ministry from September to December 2020. Using a qualitative approach as a backdrop, this project uses semi-structured interviews to collect data. Participants were briefed on the purpose of the study and consented to be interviewed and to record their interviews. Some of the participants chose to conceal their names. All the interviews were conducted in Arabic via Zoom. The researcher then transcribed and translated the interviews into English. A purposive sample is used to select the seven interviewees, based on their prominence and experience in the field of counter-extremism and Al-Azhar affairs. The researcher uses a snowball sample to select the sample, in which a personal contact recommends other officials within the establishment.

Keywords: Al-Azhar, Egypt, Counter-Extremism, Political Islam, Ideology

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Authors: Benjamin L. Freidman, Sally L. Gras, Ian Snape, Geoff W. Stevens, Kathryn A. Mumford

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Increasing transportation and storage of petroleum hydrocarbons in Antarctic and sub-Antarctic regions have resulted in frequent accidental spills. Migrating petroleum hydrocarbon spills can have a significant impact on terrestrial and marine ecosystems in cold regions, as harsh environmental conditions result in heightened sensitivity to pollution. This migration of contaminants has led to the development of Permeable Reactive Barriers (PRB) for application in cold regions. PRB’s are one of the most practical technologies for on-site or in-situ groundwater remediation in cold regions due to their minimal energy, monitoring and maintenance requirements. The Main Power House site has been used as a fuel storage and power generation area for the Macquarie Island research station since at least 1960. Soil analysis at the site has revealed Total Petroleum Hydrocarbon (TPH) (C9-C28) concentrations as high as 19,000 mg/kg soil. Groundwater TPH concentrations at this site can exceed 350 mg/L TPH. Ongoing migration of petroleum hydrocarbons into the neighbouring marine ecosystem resulted in the installation of a ‘funnel and gate’ PRB in November 2014. The ‘funnel and gate’ design successfully intercepted contaminated groundwater and analysis of TPH retention and biodegradation on PRB media are currently underway. Installation of the PRB facilitates research aimed at better understanding the contribution of particle attached biofilms to the remediation of groundwater systems. Bench-scale PRB system analysis at The University of Melbourne is currently examining the role biofilms play in petroleum hydrocarbon degradation, and how controlled release nutrient media can heighten the metabolic activity of biofilms in cold regions in the presence of low temperatures and low nutrient groundwater.

Keywords: groundwater, petroleum, Macquarie island, funnel and gate

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Authors: Jeremy Bost, Matthew Brett, Jacob Flynn, Weihui Li

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One response during anaphylaxis is reduced blood pressure due to blood vessels relaxing and dilating. Epinephrine causes the blood vessels to constrict, which raises blood pressure to counteract the symptoms. When going through an allergic reaction, an Epinephrine injector is used to administer a shot of epinephrine intramuscularly. Epinephrine injectors have become an integral part of day-to-day life for people with allergies. Current Epinephrine injectors (EpiPen) are completely mechanical and have no sensors to monitor the vital signs of patients or give suggestions the optimal time for the shot. The EpiPens are also large and inconvenient to carry daily. The current price of an EpiPen is roughly 600$ for a pack of two. This makes carrying an EpiPen very expensive, especially when they need to be switched out when the epinephrine expires. This new design is in the form of a bracelet, which has the ability to inject epinephrine. The bracelet will be equipped with vital signs monitors that can aid the patient to sense the allergic reaction. The vital signs that would be of interest are blood pressure, heart rate and Electrodermal activity (EDA). The heart rate of the patient will be tracked by a photoplethysmograph (PPG) that is incorporated into the sensors. The heart rate is expected to increase during anaphylaxis. Blood pressure will be monitored through a radar sensor, which monitors the phase changes in electromagnetic waves as they reflect off of the blood vessel. EDA is under autonomic control. Allergen-induced anaphylaxis is caused by a release of chemical mediators from mast cells and basophils, thus changes the autonomic activity of the patient. So by measuring EDA, it will give the wearer an alert on how their autonomic nervous system is reacting. After the vital signs are collected, they will be sent to an application on a smartphone to be analyzed, which can then alert an emergency contact if the epinephrine injector on the bracelet is activated. Overall, this design creates a safer system by aiding the user in keeping track of their epinephrine injector, while making it easier to track their vital signs. Also, our design will be more affordable and more convenient to replace. Rather than replacing the entire product, only the needle and drug will be switched out and not the entire design.

Keywords: allergy, anaphylaxis, epinephrine, injector, vital signs monitor

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Authors: O. E. Eberechi, G. P. Stevens

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Legal theory has been referred to as the explanation of why things do or do not happen. It also describes situations and why they ensue. It provides a normative framework by which things are regulated and a foundation for the establishment of legal mechanisms/institutions that can bring about a desired change in a society. Furthermore, it offers recommendations in resolving practical problems and describes what the law is, what the law ought to be and defines the legal landscape generally. Some legal theories provide a universal standard, e.g. human rights, while others are capable of organizing and streamlining the collective use, and, by extension, bring order to society. Legal theory is used to explain how the world works and how it does not work. This paper will argue for the application of the principles of legal theory in the achievement of access to justice for female victims of sexual violence in refugee camps in Africa through the analysis of legal theories underpinning the access to justice for these women. It is a known fact that female refugees in camps in Africa often experience some form of sexual violation. The perpetrators of these incidents may never be apprehended, prosecuted, convicted or sentenced. Where prosecution does occur, the perpetrators are either acquitted as a result of poor investigation, inept prosecution, a lack of evidence, or the case may be dismissed owing to tardiness on the part of the prosecutor, which accounts for the culture of impunity in refugee camps. In other words, victims do not have access to the justice that could ameliorate the plight of the victims. There is, thus, a need for a legal framework that will facilitate access to justice for these victims. This paper will start with an introduction, and be followed by the definition of legal theory, its functions and its application in law. Secondly, it will provide a brief explanation of the problems faced by female refugees who are victims of sexual violence in refugee camps in Africa. Thirdly, it will embark on an analysis of theories which will be a help to an understanding of the precarious situation of female refugees, why they are violated, the need for access to justice for these victims, and the principles of legal theory in its usefulness in resolving access to justice for these victims.

Keywords: access to justice, underpinning legal theory, refugee, sexual violence

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Authors: Saarah Juman, Ilona Johnson, Stephen Richmond, Brett Duane, Sheelagh Rogers

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Introduction: Researchers suggest that within 50 years or less, the available supply of a range of metals will be exhausted, potentially leading to increases in resource conflict and largescale production shortages. The healthcare, dental and orthodontic sectors will undoubtedly be affected as stainless steel instruments are generally heavily relied on. Although changing orthodontic archwires are unavoidable and necessary to allow orthodontic tooth movement through the progression of an archwire sequence with fixed appliances, they are thought to be manufactured in excess of what is needed. Furthermore, orthodontic archwires require trimming extraorally to allow safe intraoral insertion, thus contributing to unnecessary waste of natural resources. Currently, there is no evidence to support the optimisation of archwire length according to orthodontic fixed appliance stage. As such, this study aims to quantify archwire excess (extraoral archwire trimmings) for different stages of orthodontic fixed appliance treatment. Methodology: This prospective, observational, quantitative study observed trimmings made extraorally against pre-treatment study models by clinicians over a 3-month period. Archwires were categorised into one of three categories (initial aligning, sequence, working/finishing arcwhires) within the orthodontic fixed appliance archwire sequence. Data collection included archwire material composition and the corresponding length and weight of excess archwire. Data was entered using a Microsoft Excel spreadsheet and imported into statistical software to obtain simple descriptive statistics. Results: Measurements were obtained for a total of 144 archwires. Archwire materials included nickel titanium and stainless steel. All archwires observed required extraorally trimming to allow safe intraoral insertion. The manufactured lengths of orthodontic initial aligning, sequence, and working/finishing arcwhires were at least 31%, 26%, and 39% in excess, respectively. Conclusions: Orthodontic archwires are manufactured to be excessively long at all orthodontic archwire sequence stages. To conserve natural resources, this study’s findings support the optimisation of orthodontic archwire lengths by manufacturers according to the typical stages of an orthodontic archwire sequence.

Keywords: archwire, orthodontics, sustainability, waste

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Authors: Jaan-Willem Simon, Bertram Stier, Brett Bednarcyk, Evan Pineda, Stefanie Reese

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Textile composites, in which the reinforcing fibers are woven or braided, have become very popular in numerous applications in aerospace, automotive, and maritime industry. These textile composites are advantageous due to their ease of manufacture, damage tolerance, and relatively low cost. However, physics-based modeling of the mechanical behavior of textile composites is challenging. Compared to their unidirectional counterparts, textile composites introduce additional geometric complexities, which cause significant local stress and strain concentrations. Since these internal concentrations are primary drivers of nonlinearity, damage, and failure within textile composites, they must be taken into account in order for the models to be predictive. The macro-scale approach to modeling textile-reinforced composites treats the whole composite as an effective, homogenized material. This approach is very computationally efficient, but it cannot be considered predictive beyond the elastic regime because the complex microstructural geometry is not considered. Further, this approach can, at best, offer a phenomenological treatment of nonlinear deformation and failure. In contrast, the mesoscale approach to modeling textile composites explicitly considers the internal geometry of the reinforcing tows, and thus, their interaction, and the effects of their curved paths can be modeled. The tows are treated as effective (homogenized) materials, requiring the use of anisotropic material models to capture their behavior. Finally, the micro-scale approach goes one level lower, modeling the individual filaments that constitute the tows. This paper will compare meso- and micro-scale approaches to modeling the deformation, damage, and failure of textile-reinforced polymer matrix composites. For the mesoscale approach, the woven composite architecture will be modeled using the finite element method, and an anisotropic damage model for the tows will be employed to capture the local nonlinear behavior. For the micro-scale, two different models will be used, the one being based on the finite element method, whereas the other one makes use of an embedded semi-analytical approach. The goal will be the comparison and evaluation of these approaches to modeling textile-reinforced composites in terms of accuracy, efficiency, and utility.

Keywords: multiscale modeling, continuum damage model, damage interaction, textile composites

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