Development and Production of Cellulose Nanocrystal Fillers, PVA Fibers and Composite PVA/CNC Fibers with Electro-Spray/Spinning for Application in Thermoplastic Reinforcement

The work within this dissertation involved the production and utilization of cellulose nanomaterials within the context of electrospraying and electrospinning. The production of nano-dimension cellulose nanocrystal (CNC) powders was a novel contribution to the multi-decade efforts surrounding the drying of CNC suspensions, and the powders were produced by electrospraying reduced surface tension suspensions at room temperature. The CNC powders were used as a control for comparison with electrospun fibers in thermoplastic composites. Nano-diameter (submicron) fibers generated most of the work outlined in this dissertation and were produced using a water-soluble, sustainably derived, poly (vinyl alcohol) (PVA). The CNC suspension was added to the PVA and water as the polymer dissolved to create a composite electrospinning solution. The addition of 50 wt.% CNC suspension to the PVA solution increased the viscosity and ultimately decreased the fiber production capacity. However, by slightly reducing the CNC content to 40 wt.%, electrospun fibers could be consistently produced. The fiber diameters were measured and analyzed by a 3x3 factorial experimental iii design involving the addition of 0, 20 and 40 wt.% CNC in PVA solutions and altering the machine settings to produce varied samples. The measurement sampling methodology created the most variation in fiber diameter, rather than the machine settings. While obtaining information about the fiber production characteristics, spun mats were collected and post processed for application as a fiber reinforcement in a thermoplastic poly (lactic acid) (PLA) matrix. The PLA polymer was chosen because it has chemical compatibility with both PVA and CNC as well as sustainable attributes. By reinforcing PLA with 15% composite nanofiber (cNF) composed of 20 wt.% CNC loaded PVA fibers via melt compounding, improvements in the mechanical and thermal properties were observed. The neat PLA tensile modulus increased 30% from 3.64 ± 0.76 to 4.74 ± 0.34 GPa and the tensile strength increased 21% from 56.4 ± 13.6 to 68.3 ± 1.2 MPa. Impact strength showed significant improvement, increasing 54% from 3.15 ± 0.26 to 4.85 ± 0.86 MJ/cm3. The flexural modulus showed a 6% improvement from 3.68 ± 0.09 to 3.91 ± 0.21 GPa and the flexural strength increased 1% from 99.65 ± 6.4 to 100.4 ± 0.6 GPa. The fiber reinforcement contributed to improvements in tensile properties without sacrificing flexural properties or impact strength as normally observed in composites containing microscale CNC powders. This improvement can contribute to additional applications for thermoplastic PLA and the electrospun fiber reinforcement methodology shows applicability to other polymer systems

Comparing open and minimally invasive surgical procedures for oesophagectomy in the treatment of cancer: the ROMIO (Randomised Oesophagectomy: Minimally Invasive or Open) feasibility study and pilot trial

Localised oesophageal cancer can be curatively treated with surgery (oesophagectomy) but the procedure is complex with a risk of complications, negative effects on quality of life and a recovery period of 6-9 months. Minimal-access surgery may accelerate recovery.The ROMIO (Randomised Oesophagectomy: Minimally Invasive or Open) study aimed to establish the feasibility of, and methodology for, a definitive trial comparing minimally invasive and open surgery for oesophagectomy. Objectives were to quantify the number of eligible patients in a pilot trial; develop surgical manuals as the basis for quality assurance; standardise pathological processing; establish a method to blind patients to their allocation in the first week post surgery; identify measures of postsurgical outcome of importance to patients and clinicians; and establish the main cost differences between the surgical approaches.Pilot parallel three-arm randomised controlled trial nested within feasibility work.Two UK NHS departments of upper gastrointestinal surgery.Patients aged ≥ 18 years with histopathological evidence of oesophageal or oesophagogastric junctional adenocarcinoma, squamous cell cancer or high-grade dysplasia, referred for oesophagectomy or oesophagectomy following neoadjuvant chemo(radio)therapy.Oesophagectomy, with patients randomised to open surgery, a hybrid open chest and minimally invasive abdomen or totally minimally invasive access.The primary outcome measure for the pilot trial was the number of patients recruited per month, with the main trial considered feasible if at least 2.5 patients per month were recruited.During 21 months of recruitment, 263 patients were assessed for eligibility; of these, 135 (51%) were found to be eligible and 104 (77%) agreed to participate, an average of five patients per month. In total, 41 patients were allocated to open surgery, 43 to the hybrid procedure and 20 to totally minimally invasive surgery. Recruitment is continuing, allowing a seamless transition into the definitive trial. Consequently, the database is unlocked at the time of writing and data presented here are for patients recruited by 31 August 2014. Random allocation achieved a good balance between the arms of the study, which, as a high proportion of patients underwent their allocated surgery (69/79, 87%), ensured a fair comparison between the interventions. Dressing patients with large bandages, covering all possible incisions, was successful in keeping patients blind while pain was assessed during the first week post surgery. Postsurgical length of stay and risk of adverse events were within the typical range for this group of patients, with one death occurring within 30 days among 76 patients. There were good completion rates for the assessment of pain at 6 days post surgery (88%) and of the patient-reported outcomes at 6 weeks post randomisation (74%).Rapid recruitment to the pilot trial and the successful refinement of methodology indicated the feasibility of a definitive trial comparing different approaches to oesophagectomy. Although we have shown a full trial of open compared with minimally invasive oesophagectomy to be feasible, this is necessarily based on our findings from the two clinical centres that we could include in this small preliminary study.Current Controlled Trials ISRCTN59036820.This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 48. See the NIHR Journals Library website for further project information

Challenges of HIV diagnosis and management in the context of pre-exposure prophylaxis (PrEP), post-exposure prophylaxis (PEP), test and start and acute HIV infection: a scoping review

Introduction: Knowledge of HIV status relies on accurate HIV testing, and is the first step towards access to HIV treatment and prevention programmes. Globally, HIV-status unawareness represents a significant challenge for achieving zero new HIV infections and deaths. In order to enhance knowledge of HIV status, the World Health Organisation (WHO) recommends a testing strategy that includes the use of HIV-specific antibody point-of-care tests (POCT). These POCTs do not detect acute HIV infection, the stage of disease when viral load is highest but HIV antibodies are undetectable. Complicating things further, in the presence of antiretroviral therapy (ART) for pre-exposure prophylaxis (PrEP) or post-exposure prophylaxis (PEP), other currently available testing technologies, such as viral load detection for diagnosis of acute HIV infection, may yield false negative results. In this scoping review, we evaluate the evidence and discuss alternative HIV testing algorithms that may mitigate diagnostic dilemmas in the setting of increased utilisation of ART for immediate treatment and prevention of HIV infection. Discussion: Missed acute HIV infection prevents people living with HIV (PLWH) from accessing early treatment, increases likelihood of onward transmission, and allows for inappropriate initiation or continuation of PrEP, which may result in HIV drug resistance. Whilst immediate ART is recommended for all PLWH, studies have shown that starting ART in the setting of acute HIV infection may result in a delayed or complete absence of development of HIV-specific antibodies, posing a diagnostic challenge that is particularly pertinent to resource-limited, high HIV burden settings where HIV-antibody POCTs are standard of care. Similarly, ART used as PrEP or PEP may supress HIV RNA viral load, complicating current HIV testing algorithms in resource-wealthy settings where viral detection is included. As roll-out of PrEP continues, HIV testing algorithms may need to be modified. Conclusions: With increasing use of PrEP and ART in acute infection we anticipate diagnostic challenges using currently available HIV testing strategies. Research and surveillance is needed to determine the most appropriate assays and optimal testing algorithms that are accurate, affordable and sustainable

Predicting sexual problems in women: The relevance of sexual excitation and sexual inhibition

This is the post-print version of the article. The official published version can be obtained from the link below.Data from a non-clinical sample of 540 heterosexual women were used to examine the relationships between scores on the Sexual Excitation/Sexual Inhibition Inventory for Women (SESII-W) and ratings of current sexual problems, lifetime arousal difficulty, lifetime orgasm difficulty, and lifetime problems with low sexual interest. Multiple regression analyses also included several demographic/background variables as predictors: age, full-time employment, completed college, children in household, married, health ratings, importance of sex, and whether the woman was in a sexual relationship. The strongest statistical predictors of both current and lifetime sexual problems were the SESII-W inhibition factors Arousal Contingency and Concerns about Sexual Function. Demographic factors did not feature largely in any of the models predicting sexual problems even when statistically significant relationships were found. If future research supports the predictive utility of the SESII-W in identifying women who are more likely to experience sexual difficulties, these scales may be used as prognostic factors in treatment studies.This study was funded, in part, by a grant from the Lilly Centre for Women's Health

Manacled to Identity: Cosmopolitanism, Class, and ‘The Culture Concept’ in Stephen Crane

This article begins with a close reading of Stephen Crane’s short story ‘Manacled’ from 1900, which situates this rarely considered short work within the context of contemporary debates about realism. I then proceed to argue that many of the debates raised by the tale have an afterlife in our own era of American literary studies, which has frequently focused on questions of ‘identity’ and ‘culture’ in its reading of realism and naturalism to the exclusion of the importance of cosmopolitan discourses of diffusion and exchange across national borders. I then offer a brief reading of Crane’s novel George’s Mother, which follows Walter Benn Michaels in suggesting that the recent critical attention paid to particularities of cultural difference in American studies have come to conflate ideas of class and social position with ideas of culture in ways that have ultimately obscured the presence of genuine historical inequalities in US society. In order to challenge this critical commonplace, I situate Crane’s work within a history of transatlantic cosmopolitanism associated with the ideas of Franz Boas and Matthew Arnold to demonstrate the ways in which Crane’s narratives sought out an experience of the universal within their treatments of the particular

Engaging People with Energy Efficiency: A Randomised Controlled Trial Testing the Effects of Thermal Imaging Visuals in a Letter Communication

The study tested the effect of adding visualisations to a communication to engage householders with an energy efficiency programme. External wall insulation is an appropriate way of insulating homes, yet take-up is low. Householders may be unaware of the heat loss from uninsulated walls. In earlier research, seeing thermal images prompted the uptake of simple energy efficiency actions amongst householders. Thermal images were added to a standard letter to visualise heat transfer from a home before and after external wall insulation had been installed. A randomised controlled trial tested three types of letter (standard, standard plus thermal image showing problem, standard plus thermal images showing problem and solution) in 5483 UK households. The target outcome was the rate of telephone enquiries after exposure to the letters. Enquiry rates were low (1.6%) and did not differ between letter type. We discuss the null effect in relation to the target action (external wall insulation), the manner of presentation of the visuals (mass communication, letter through the door) and the ingredients of a persuasive intervention. Findings suggest that taking a key ingredient from an intervention and applying it in a different context may result in the loss of its impact.</jats:p

A simplified extractive metallurgy exercise to demonstrate selective extraction of copper

A laboratory activity is described for senior high school or 1st year undergraduate level students that illustrates key concepts linked to extractive metallurgy. This experiment demonstrates preferential binding of a methoxyphenolic oxime ligand to Cu2+ in the presence of other transition metal ions in aqueous solution. The students are tasked to investigate the importance of the spatial relationship between the oxime and phenol group of two potential ligands by performing a series of short and simple tests. The objective is achieved by identifying which methoxyphenolic oxime ligand selectively and rapidly forms an isolable precipitate with Cu2+ ions. Only one of the potential ligands exhibits a clear preference for binding to Cu2+ and this can easily be identified visually (and confirmed by UV-visible spectroscopy if desired). The experiment has successfully been employed as part of an extracurricular laboratory course involving groups of 25-30 high school students.PostprintPeer reviewe

The Tensor-Vector-Scalar theory and its cosmology

Over the last few decades, astronomers and cosmologists have accumulated vast amounts of data clearly demonstrating that our current theories of fundamental particles and of gravity are inadequate to explain the observed discrepancy between the dynamics and the distribution of the visible matter in the Universe. The Modified Newtonian Dynamics (MOND) proposal aims at solving the problem by postulating that Newton's second law of motion is modified for accelerations smaller than ~10^{-10}m/s^2. This simple amendment, has had tremendous success in explaining galactic rotation curves. However, being non-relativistic, it cannot make firm predictions for cosmology. A relativistic theory called Tensor-Vector-Scalar (TeVeS) has been proposed by Bekenstein building on earlier work of Sanders which has a MOND limit for non-relativistic systems. In this article I give a short introduction to TeVeS theory and focus on its predictions for cosmology as well as some non-cosmological studies.Comment: 44 pages, topical review for Classical and Quantum Gravit

Person-centred experiential therapy (PCET) training within a UK NHS IAPT service: experiences of selected counsellors in the PRaCTICED trial

We investigated the experiences of 10 counsellors undergoing training in a form of person-centred experiential therapy (PCET), known in the UK as Counselling for Depression (CfD). Training was delivered at a service level as part of the PRaCTICED trial. Counsellors who took part in the study either completed (N=5), failed to complete (N=3) or were ongoing (N = 2) in their PCET training. Framework analysis was selected to extract rich data and an in-depth account of counsellors’ experiences. Inconsistencies were reported between counsellors’ previous theoretical backgrounds and PCET. Difficulties were also reported in resolving person-centred and emotion-focused elements of PCET. Key facilitators and barriers to completing PCET training were identified, including counsellors’ intrapersonal factors