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Graphene functionalisation of wool and cotton textiles to confer sensing capability
No full textIndividual and societal expectations of apparel performance are surpassing the three key requirements of physical, psychological, and social protection. Users are increasingly envisaging integrated technologies to facilitate daily life and specialist applications. Electrical conductivity and sensor performance is an integral component of this and can be achieved by applying functionalising treatments. Of increasing interest are graphene-based treatments (i.e. reduced graphene oxide, graphene ink) applied to apparel fabrics based on high conductivity, strength, and light weight of the two-dimensional honey comb structure. Knits manufactured of natural fibres are most suited for apparel applications, especially those worn next to the skin. Research has focussed on functionalised cotton fabrics with less focus on wool fabrics. Exploration into knit constructions has been limited. Performance of fabrics manufactured from wool and cotton fibres are often linked to hydrophilicity. A pre-treatment may be required to reduce hydrophobicity caused by presence of oils or waxes remaining on finished wool or cotton fabrics respectively, or application of additional, or lack thereof, of processing treatments (e.g. chlorination, scouring, mercerisation).
Single jersey 100% merino wool and 100% cotton were selected as trial fabrics. Hydrophobic properties were determined using wettability tests (water absorbency time, contact angle, liquid absorptive capacity). A chemical pre-treatment was developed and optimised for concentration of the active ingredient and treatment time for each knit, potassium hydroxide for wool and for cotton, sodium hydroxide. One concentration and time was selected for knit constructed of wool (0.05mol/L, 15min) and cotton (2mol/L, 30min). Wettability increased based on decreased water absorbency time, contact angle; and increased liquid absorptive capacity and moisture regain with no evidence of degradation to the fabric, yarns, or fibres assumed from visual appearance (photographs, microscope images), surface chemistry based on infrared spectra, and fabric structural properties of mass, thickness, and stitch density.
Subsequently each knit was functionalised with one of two treatments, reduced graphene oxide stabilised with poly(sodium 4-styrenesulfonate) or graphene ink. Several functionalisation process variables were investigated where appropriate (e.g. prior pre-treatment, graphene concentration, treatment time, curing temperature, and curing time). The small-scale experiment involved investigation of deposits (photographs, microscopic images), conductivity, and durability to wash. The most critical parameters for the functionalisation treatments were identified, and levels selected that may confer desirable performance based on the aforementioned properties. Further examination was undertaken to optimise treatment time and curing temperature of reduced graphene oxide functionalisation on wool (8min, 24min; 110°C, 120°C) and cotton (20min, 40min; 70°C, 120°C). Graphene ink was applied with one optimum treatment time to the wool (16min) and cotton (40min). Properties investigated included visual evidence of graphene deposits based on photographs, optical microscope images, image analysis, scanning electron microscope, and colour coordinates (L*, a*, b*). Differences in surface chemistry were also identified based on infrared and Raman spectra. Electrical conductivity was calculated from measurements of electrical resistance. Changes to fabric structure were determined from measurements of mass, thickness, stitch density and performance properties included flexural rigidity, water absorbency time, contact angle, liquid absorptive capacity, regain, permeability to water vapour, permeability to air, and tactile acceptability. Durability to wash, abrasion, and storage were determined based on change or lack thereof in electrical conductivity and
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appearance (photographs, optical microscope, and colour coordinates) with exposure to sequential cycles.
Deposits of graphene treatments were assumed based on visual change from cream to dark grey and presence of nonfibrous deposits. Pixel intensity mean, minimum, and mode were lower compared to the non-treated knits. Maximum pixel intensity was similar for fabrics graphene treated and not. Fibre width and area of the region of interest were least affected by the graphene treatments. Lightness (L*) was smallest of fabrics graphene treated although a* and b* were not affected. Changes occurred to surface chemistry based on infrared and Raman spectral analysis indicative of the carbon composition of the graphene treatments. FTIR provided limited evidence with low merits for understanding deposits of the graphene treatments while Raman provided more definitive evidence of graphene presence.
Conductivity was conferred from graphene deposits with small effects on structural characteristics of the knits (mass, thickness, stitch density) and performance properties including stiffness, water absorbency time, liquid absorptive capacity, contact angle, moisture regain, permeability water vapour and to air, and tactile acceptability. Minimal changes to the fabric structure and performance properties suggest acceptability to be used in next-to-skin apparel. Durability to wash (20 cycles for reduced graphene oxide, 100 cycles for graphene ink), abrasion (50,000 for graphene ink), and storage (28 days for reduced graphene oxide, 365 days for graphene ink) were a challenge, where conductivity decreased, sometimes being lost from the fabrics functionalised with reduced graphene oxide. Similar trends occurred with both the wool and cotton knit following functionalisation with graphene treatments. Graphene ink functionalisation produced knits with superior functionality, especially in terms of electrical conductivity and effects of exposure to wash, abrasion, and storage. Graphene ink functionalised specimens were selected for further investigation of encapsulation to enhance performance, primarily increasing durability without compromising fabric structure or performance properties1.
Encapsulation of functionalised fabrics with substances impervious to external elements, that have potential to cause degradation of treatment deposits and electrical conductivity, can attenuate negative effects. Exposure to wash (100 cycles), abrasion (50,000 cycles), and storage (365 days) were considered critical, however, modification of fabric structure and performance caused by encapsulation can result in a product that is non-textile like, potentially undesirable for next-to-skin apparel. Three polydimethylsiloxane-based products were selected for encapsulating the two knits functionalised with graphene ink. Each encapsulant differed in effects on fabric structure and performance properties, as well as durability. The SYLGARDTM 184 Silicone Elastomer Kit resulted in a finished product that was most dissimilar to the original knits including changed visual properties (photographs, optical and scanning electron microscope images) and surface chemistry (infrared and Raman spectra); increased mass, thickness, stitch density, stiffness, water absorbency time, contact angle, regain, permeability to water vapour and to air; with decreased liquid absorptive capacity, and tactile acceptability. Superior durability to wash, abrasion, and storage was achieved in terms of maintenance of treatment deposits and electrical conductivity. Granger's® Clothing Repel and the polydimethylsiloxane polymer conferred durability to a lesser extent but maintained similar
1 Sourcing issues of reduced graphene oxide also restricted availability for further investigation. ii
fabric structural and performance properties to the original state of knits. Prioritisation for conferring durability or retaining conventional fabric structure and performance is required. For a small- confined patch, properties pertinent to next-to-skin performance may be compromised to ensure durability .
Sensor performance was based on measurable changes in conductivity with exposure to differences in air temperature and humidity (20°C, 65%RH to 30°C, 30%RH or 35°C, 23%RH), to wetting by immersion and droplet exposure, and to changing carbon dioxide air concentration. Each can provide information to support health of the user by providing measurements of garment microclimate temperature and humidity, wetting sourced from the body or external environment, and carbon dioxide concentration of breath or small confined environmental spaces. Conductivity of the wool knit reduced graphene oxide functionalised increased with increased temperature and decreased humidity, often not recovering to the initial conductivity. The same response was shown of graphene ink and encapsulated specimens except for those encapsulated with SYLGARDTM, where wool specimens had minimal change and cotton the opposite trend of decreased conductivity with exposure to increased temperature and decreased humidity. Exposure to wetting by full immersion and droplets evoked an increase in mass and conductivity of graphene ink functionalised and encapsulated wool and cotton knits. Conductivity decreased as the functionalised knits dried. After complete drying, conductivity was less than the initial measurement. Immersion resulted in greater change compared to droplet wetting. Small changes occurred for specimens encapsulated with SYLGARDTM. No change in conductivity of graphene ink functionalised wool or cotton knits arose with exposure to carbon dioxide. Thus, sensor performance was possible for moisture (vapour, liquid) but not carbon dioxide. Fluctuating carbon dioxide concentrations will not interfere with the moisture sensing function, ensuring validity in this respect
A morphological study of the deep muscles in the flexor compartment of the leg
Get PDFPurpose: The deep muscles in the flexor compartment of the leg, comprised of tibialis posterior (TP), flexor digitorum longus (FDL) and flexor hallucis longus (FHL) contribute to ankle plantarflexion, ankle inversion and toe flexion. Investigation of these muscles may have future clinical applications given their prominent role in dynamically supporting the medial longitudinal arch of the foot. Without the action of the deep flexors, most notably TP, the arch may collapse, resulting in adult acquired flat foot. The aim of this study was to characterise the anatomy of the deep leg flexors and produce accurate data detailing the proximal muscle attachments and muscle architecture.
Methods: Four legs (4 cadavers, 2 males, mean age: 82 ± 11.8 years) were dissected. Muscle architectural parameters (e.g., muscle, tendon and musculotendinous junction length [MTJ], and physiological cross-sectional area [PCSA]; fascicular length and volume) were measured. Proximal insertion sites were quantified to obtain cross sectional area [CSA] using a 3D laser scanner and the 3D area of insertion for each muscle was digitally measured, using Blender. All data were entered into Microsoft Excel. Anatomical dimensions were normalised to leg length, and descriptive statistics were calculated.
Results: Of the three deep flexors, TP was the largest for all architectural parameters (e.g. muscle PCSA TP (16.3 ± 1.0cm2) FDL(1.9 ± 0.2) cm2, FHL (8.2 ± 3.4cm2) or volume TP (34.6 ± 6.2cm3), FDL (11.0 ± 2.1cm3) and FHL (31.2 ± 12.8cm3)) except distal MTJ and free tendon length. Proximal insertion sites were more complex in TP and there was greater muscle fusion from overlying muscles compared to FDL and FHL. Tibialis posterior had a mean proximal insertional cross-sectional area of 111.4 cm2 compared to the smaller FHL (14.7 cm2) and FDL (20.9 cm2). The proximal MTJ comprised a large percentage of muscle length, ranging from 69% (TP) to 82.5% (FDL) of the total muscle length.
Conclusion:
These findings demonstrate that of the deep flexors, TP is the largest in terms of both its insertional CSA and PCSA. Physiological cross-sectional area directly reflects the force production of a muscle, meaning that TP is likely the strongest invertor and plantarflexor of these three muscles, highlighting its important role in maintaining the medial longitudinal arch. The long proximal MTJs span at least two-thirds the length of each muscle, and this knowledge is clinically relevant for diagnosing injuries that occur in this region of the muscle-tendinous unit. Further study is needed to investigate the muscle fusion, innervation, and compartmentalisation; anatomically separate regions that are activated differentially during specific movements. The presence of these compartments may change how we consider clinical applications such as neuromuscular stimulation to strengthen muscles
Investigating the role of Fn14 expression in hormone receptor positive breast cancer
No full textBreast cancer is the second leading cause of cancer death in women. Approximately 75% of invasive breast cancers are hormone receptor (HR) positive, and have the option to receive targeted endocrine therapy. However, a significant proportion of these patients will develop resistance to this treatment, through mechanisms that remain poorly understood.
Fibroblast Growth Factor Inducible 14 (Fn14), a tumour necrosis factor receptor family member, is expressed in 76% of invasive breast cancers, and not in normal mammary epithelium. Fn14 expression correlates with progression in HR-negative tumours, but the role of aberrant Fn14 expression in HR-positive disease is unclear.
We investigated a series of HR-positive breast cancer cell lines derived from MCF7 and T47D cells, engineered to stably overexpress Fn14. Fn14 expression status was first confirmed by western blotting, with negligible expression observed in wildtype, and empty vector controls. The 2D morphology of Fn14-positive cell lines appeared more mesenchymal, with frequent pseudopodia, compared to controls. MCF7 and T47D 3D-mammopsheres were smaller in size and more nodular in Fn14-positive cell lines compared to controls. Fn14-positive MCF7 cells did not show increased invasive capacity through Matrigel-Boyden chambers, which contrasts with increased invasion following transient Fn14 expression in MCF7 cells.
Fn14+ MCF7 cell lines proliferated in 2D culture at a consistently reduced rate in complete medium, compared to control cell lines. Similar to wildtype MCF7, Fn14-positive MCF7 cell lines were not able to proliferate in hormone-deprived medium, indicating forced Fn14 expression alone, is not sufficient to drive proliferation in MCF7 cell lines. All MCF7-derived cell lines could however, be stimulated to proliferate with 10 nM 17-beta-oestradiol (E2), however E2-stimulated growth of Fn14-positive MCF7 cell lines was less robust, suggesting Fn14 is disruptive to oestrogen signalling.
Receptor Tyrosine Kinase (RTK) signalling is antagonistic to oestrogen signalling in breast cancer, and has been linked with development of resistance to anti-oestrogens. We observed activation of ERK1/2 (one of 3 MAPK pathways driven by RTK signalling) in Fn14-positive T47D cells by western blotting. ERK1/2 did not however, appear activated by Fn14 in MCF7 cells. Finally, Fn14-positive MCF7 cell lines showed a modest increase in resistance to a dose escalation of 4-hydroxy tamoxifen.
Together our data suggest that aberrant overexpression of Fn14 in HR-positive breast cancer cell lines reduces their proliferative response to E2 and reduces their sensitivity to Tamoxifen. The mechanism by which this occurs may involve signalling antagonism through RTKs, and warrants further investigation
Allelic Diversity of the Pharmacogene CYP2D6 in Māori and Pasifika
Get PDFCYP2D6 is an important pharmacogene encoding an enzyme by the same name, responsible for metabolising around 25% of commonly prescribed drugs. These include cardiac drugs such as metoprolol, the pain medication codeine, antidepressants such as fluoxetine, and many others. CYP2D6 is a highly variable gene, with some individuals carrying whole gene duplications or deletions, or any number of variants that can alter enzymatic activity. These lead to four different metaboliser phenotypes, termed poor, intermediate, normal, and ultra-rapid. Different metaboliser phenotypes can lead to varying reponses from prescribed medicine, repercussions of which include lack of therapeutic effect through to adverse drug reactions. Very little research has been carried out on this gene in Māori and Pasifika individuals, thus the frequency of CYP2D6 variants and corresponding metaboliser phenotypes within these populations are largely unknown.
We used nanopore sequencing and bioinformatic analyses to interrogate the CYP2D6 gene of 120 Māori and Pasifika individuals, identifying eight different star alleles, six novel variants and four potentially novel subvariants. One of these novel variants is exonic and non-synonymous, potentially altering enzymatic activity.
Of the identified star alleles, the apparently rare *71 allele was found at a high frequency among participants. This allele has only been discovered in a handful of prior studies and always at a very low frequency. To date, its function has not been described.
The majority of individuals in our study were assigned a normal metaboliser status based on their CYP2D6 genotypes. 5% were classed as intermediate metabolisers (reduced drug metabolism). 20% of the cohort were unable to be assigned a metaboliser phenotype due to the presence of one or more *71 alleles.
No individuals were identified as carrying a gene duplication. Five individuals carried a single gene deletion (*5), leaving them with only one remaining copy of CYP2D6.
The Māori and Pasifika population allele frequencies identified in this study were not found to correlate well with those reported for the Oceania region, revealing an obvious lack of research and quality data for this region.
This study has further demonstrated the utility of nanopore sequencing for CYP2D6 analysis. It is hoped these results will contribute to an equitable uptake of CYP2D6 pharmacogenetics and a future of personalised medicine that is relevant to all New Zealanders
Digging down into Property – The Downward Extent of Property: A New Zealand Perspective.
Get PDFSubsurface property rights come into focus when transport and infrastructure
tunnels are required to service urban settlement. This article investigates the
vertical extent of property in this context. It discusses common law property
theory, examines relevant case law and shows how other jurisdictions have
legislated for subsurface uses. It explores what may legitimately be
considered private and what public, and where an appropriate boundary may
lie. It finds that, just as the upper airspace is considered open for public
navigation, free of any rights claimed by a surface proprietor, subsurface
space below the depth of reasonable use by a surface proprietor should also
be considered public space. This would facilitate the Crown’s ability to
develop underground space for transport and infrastructure without the need
to negotiate with and compensate surface property owners
Dietetic care in inflammatory bowel disease in New Zealand
Get PDFBackground
Inflammatory Bowel Disease (IBD) is a chronic disease affecting increasing numbers of New Zealanders. Diet therapy plays an important role in disease treatment and management. This research project was designed to evaluate dietetic services in IBD care in New Zealand (NZ).
Aims
To investigate IBD patients’ experiences of dietetic services; evaluate the capacity of the NZ gastroenterology dietitian workforce; assess gastroenterologists’ experience of NZ IBD dietetic services and investigate differences in dietitian access for patients living in rural versus urban areas.
Methods
Online surveys of patients, dietitians and gastroenterologists were conducted in early-mid 2020. Quantitative data was analysed for statistical significance by non-parametric tests with a p-value <0.05 regarded as statistically significant. Qualitative data was analysed by thematic analysis.
Results
Responses were received from 407 IBD patients, 79 dietitians and 40 gastroenterologists. Half the patients (52%) had seen a dietitian for IBD nutrition advice. Patients more likely to have seen a dietitian were/had: Crohn’s disease (p=0.001), previous IBD surgery (p<0.001), younger (p<0.001) or receiving biologic therapy (p=0.005). Younger patients were seen faster by a dietitian than older patients (p=0.0001). There was a non-significant trend towards greater numbers of patients from urban areas having seen a dietitian than patients from rural areas.
Two-thirds (66%) of patients found the dietitian advice at least moderately useful while 18% did not. Patients who saw a dietitian in a private clinic were more likely to find the advice useful (p=0.0001), as were those who had received written advice (p<0.0001). A common theme from qualitative data was the need for dietitians to have specialist knowledge of IBD.
Almost all (97%) gastroenterologists reported that their IBD patients ask about nutrition; 57% reported that there were not enough dietitians to meet patient needs. Over 50% of dietitians saw IBD patients infrequently and 39% were not confident that they are up to date with the nutritional management of IBD. Nearly 80% would require changes to their dietetic service to allow higher numbers of IBD patients to be seen. Dietitians wished to have greater links to the IBD multidisciplinary team (MDT).
Discussion
International IBD management guidelines recommend that all patients with IBD should have access to dietetic support and nutrition therapies. NZ patients clearly do not have adequate or equitable access to dietetic services; patients wish to have ongoing dietitian access to address nutrition needs that may vary over time. Dietitians acknowledge the need for additional upskilling in the nutritional management of IBD.
Conclusion
The project achieved its key aims and concluded that current IBD dietetic services in NZ are inadequate. Increased resourcing of dietetic services and stronger links to the IBD MDT will ensure that nutrition therapy is evidence-based, collaborative and implemented in a timely manner. While some dietetic services already provide care at this level, further work is needed to guarantee that access to quality and timely dietetic care is the norm for all patients with IBD in NZ
Perceived confidence in performing peripheral venipuncture among dental practitioners in New Zealand and Malaysia
Get PDFAims: This research described the perceived confidence in performing peripheral venipuncture among dental practitioners in New Zealand and Malaysia and determined the preferred mode of training in peripheral venipuncture from the dental practitioners' perspective.
Introduction: This exploratory cross-sectional correlational, quantitative study involved the participants completing online questionnaires. The study populations were registered dental practitioners holding the current Annual Practicing Certificates during the data collection in 2020 and were either registered with the Dental Council of New Zealand or the Malaysian Dental Council. The data analysis was performed using Microsoft Excel and Statistical Package for the Social Sciences version 25.
Results: The response rates received from eligible dental practitioners in New Zealand and Malaysian represented 4.7% and 4.3% of registered, actively practising dental practitioners for each country, respectively, in 2020. In New Zealand, 44% of dental practitioners reported exposure to peripheral venipuncture as undergraduates, while in Malaysia, it was 45%.
47% of New Zealand dental practitioners reported confidence in performing peripheral venipuncture during routine dental practice and 29% during medical emergencies. In Malaysia, 21% felt confident performing peripheral venipuncture during routine dental practice, while 9% felt confident performing peripheral venipuncture during medical emergencies. In New Zealand, 65% perceived peripheral venipuncture training as essential, while in Malaysia, 81%. Both New Zealand and Malaysian dental practitioners would prefer peripheral venipuncture training through clinical activities, workshops, simulated practice with a mannequin arm, and inclusion in undergraduate and postgraduate curriculum programmes.
Conclusion: Peripheral venipuncture is a very commonly performed and essential medical procedure. A competent level of skill in performing peripheral venipuncture is a valuable asset for dental practitioners. The results of this study could be used to inform training programmes in peripheral venipuncture for dental practitioners. It is hoped that these educational resources could be deployed to maintain competence, improve skills and boost confidence in this area of patient care.
Age- and sex-specific visceral fat reference cutoffs and their association with cardio-metabolic risk
No full textParetio puzzle whale (Cetacea: Mysticeti) pieces together past and phylogeny
No full textNew Zealand rocks have yielded numerous fossil cetaceans, both odontocetes and mysticetes. Many fossil cetaceans in New Zealand come from the Waitaki valley aged around the Oligocene and Miocene. Mysticetes in New Zealand include the basal eomysticetes to crown mysticetes the ancestors of today’s baleen whales. OU22404 is a crown mysticete recovered from the Waitaki valley from the Oligocene-Miocene boundary. Plicogulae is a group of crown mysticetes the include modern rorquals and the almost extinct Cetotheriidae. OU22404 and a few other taxa, including Mauicetus and Horopeta, are basal to this group. Called stem Plicogulae, they have often occupied an unstable position within mysticete phylogeny. With the addition of OU22404 the phylogeny becomes more stable. OU22404’s anatomy shows how modern feeding methods developed. The skull shape has features not found in older mysticetes, such as adaptations to allow mandible rotation. OU22404 may have employed an early form of lunge feeding as well as a generalised form of feeding. A stepwise transition from eomysticetes to Balaenopteridae can be followed using OU22404. Around 23-17 Ma mysticetes disappeared from the global fossil record. The assemblages of mysticetes were different before and after this gap. OU22404 is dated to just after the start of this “dark age” and shows how modern mysticetes developed during this time
Dietary calcium intakes and major contributing food sources of adolescent males in New Zealand
Get PDFBackground: Calcium plays an important role in optimising bone health. Sufficient intakes are especially important during periods of growth and development, to ensure the attainment of peak bone mass- a strong predictor of later life fracture and osteoporosis risk. Adolescents have among the highest dietary calcium requirements of any lifecycle group, with an estimated average requirement of 1050 mg/day. The high calcium requirements necessary for this lifecycle group creates challenges in achieving a sufficient intake, especially when coupled with the changes in dietary patterns associated with this life period. Usual daily calcium intakes and the prevalence of inadequacy among New Zealand male adolescents is currently unknown, with the last available data captured over a decade ago. Moreover, the wider implications of changes in food consumption and supply over this period, in particular, the downward trend in consumption of milk and dairy products, could have an influence on the dietary calcium intakes of adolescents.
Objective: To determine usual dietary calcium intakes, major contributing food sources of calcium, and examine specific dietary habits known to influence calcium intakes of New Zealand male adolescents aged 15-18 years.
Design: The present study used data from a cross-sectional, multi- site survey of 135 adolescent males (15-18 years), recruited across 6 New Zealand high schools between February and March 2020. Socio-demographic and dietary habit data were collected using online questionnaires and weight and height were taken for calculation of body mass index. Dietary intake data was obtained via two 24-hr diet recalls, with the multiple source method (MSM) used to adjust for usual calcium intake. The estimated average requirement (EAR) cut-point method was applied to estimate the prevalence of inadequate calcium intake.
Results: The usual median (IQR) of calcium intakes of the sample population were low, 935 (656, 1222) mg/day . The prevalence of inadequacy was high (63%), with Asians, and those residing in low deprivation neighbourhoods identified as being at increased risk of calcium inadequacy (76% and 71%, respectively). Energy intakes appeared positively related to calcium intakes, as evident by concurrently high energy and calcium intakes among various subgroups. Milk was widely consumed among participants (77%) and as such, was the most valuable source of calcium, contributing nearly one-third (28%) to total calcium intakes of the sample population. Additional calcium contributing food groups included cheese (11%), bread (8%), bread-based dishes (6%) and non-alcoholic beverages (6%). The highest dietary calcium intakes were demonstrated among participants who reported frequently consuming milk and dairy products (several times per week, daily, or multiple times per day) and breakfast (everyday), and avoided sugar-sweetened beverages (non-consumers or rarely consumed).
Conclusion: The reported intakes of calcium were suboptimal in our sample of adolescent males, resulting in a high percentage of the population not meeting current recommended intakes. Improved calcium intakes were reported among frequent consumers of milk, dairy and breakfast, and those who avoided sugar-sweetened beverages. Given the consequences associated with failure to achieve sufficient calcium intakes during this period, a nationally representative investigation of the calcium intakes of NZ adolescent males is required, allowing for discernment of whether there is need for further interventions to address this nutritional concern