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DNADRV: Gathering insect biodiversity data by swabbing vehicle number plates
No full textLong term, standardised sampling of insect biodiversity is necessary to address the hot topics of current entomological discourse including climate driven range expansion/contraction, phenological asynchrony between insects and commensals and the longstanding controversy of “insect armageddon”. However, there are challenges in actively collecting long-term data sets over a wide geographic area. The application of eDNA to the monitoring of human population health highlights the benefits of this technology to inexpensively monitor broad trends using a waste product (e.g. SARS-CoV-2 load in sewerage), and this presents an exciting opportunity for monitoring insect populations.
When an insect collides with a car, it leaves remnant DNA that can be used to gather baseline data on the regional prevalence of insect species. Car registration plates present a perfect standardised sampling surface from which to collect samples and the ubiquity of cars allows for the public to easily get involved in the sampling.
In this poster we present the results of two preliminary studies that extract, amplify and sequence DNA from car number plates to determine the composition of regional insect assemblages. These preliminary data sets include samples taken by attendees at the Entomological Society of New Zealand Conference held in Christchurch last year.
Our results indicate the value of this approach in documenting data deficient and neglected insect taxa as well as identifying insects that are of interest for biosecurity and conservation. We also chronical how running these preliminary studies, and the consequent feedback that we have had, has led to many adjustments and refinements to the sampling kits that we are now distributing to the general public as a broad scale citizen science initiative to determine insect biodiversity. We hope that this poster foments discussions and collaborations with members of the society about how this method of sampling vast transects of insect biodiversity can be extended to Australia and elsewhere
Exploring the Tuatara Gut Microbiome: Cultivation, Whole-Genome Sequencing, and Functional Potential of Chryseobacterium
No full textTuatara are endemic to Aotearoa New Zealand and the sole extant representative of an ancient reptile order, Rhynchocephalia. While previous 16S rRNA gene-based research suggests they harbour a unique gut microbiome distinct from those of other reptiles, neither species-level taxonomy nor microbiome function have yet been characterised. This thesis research aimed to address these knowledge gaps by isolating and identifying tuatara gut bacteria (using cloacal swabs as a proxy) to improve taxonomic resolution and conduct whole-genome analysis of key isolates. Cultivation of a diversity of gut bacteria from tuatara has not previously been reported, therefore methods were adapted from work on other reptile hosts. Cloacal swabs from six tuatara were plated on nutrient and blood agar, then incubated under aerobic or anaerobic conditions at 37°C or at room temperature (~20–22°C). This cultivation approach yielded 60 bacteria belonging to 13 genera, with representatives from each of the four dominant phyla (Bacteroidota, Firmicutes, Actinobacteriota, and Proteobacteria) in the tuatara gut. This included multiple isolates of Chryseobacterium, a core bacterial genus in tuatara guts. All bacteria isolated have previously been reported in wild and captive tuatara, as well as from other reptile species. Whole-genome sequencing was completed on Oxford Nanopore for 19 tuatara isolates, with a particular focus on Chryseobacterium. Genome annotation revealed that Chryseobacterium likely plays a role in the degradation of plant polysaccharides. Though tuatara primarily consume insects, they can also consume plants and kawakawa berries, therefore the ability to digest complex plant polysaccharides is likely to be beneficial to the host. Furthermore, this may explain why Chryseobacterium is almost always present, albeit generally at low abundance. One species, C. piscium, may also play a role in host-derived glycan degradation, perhaps facilitating survival in a host that can go prolonged periods without eating. In many vertebrate hosts, including reptiles, these roles are carried out by Bacteroides spp.; however, due to documented low abundance of Bacteroides in tuatara, Chryseobacterium may occupy this important niche in the tuatara gut
Development and Characterization of LM22A-4 loaded Polymer Microparticles for Treating Spinal Cord Injury
No full textAims: Spinal Cord Injury (SCI) is a devasting condition and currently untreatable. LM22A-4 has recently been found to be a promising compound exhibiting neurotrophic effects following SCI. This thesis aimed to evaluate a treatment strategy for SCI by fabricating and characterising LM22A-4-loaded poly(lactic-co-glycolic acid) (PLGA) microparticles. The specific objectives were to i) validate an analytical method to quantify a model drug ibuprofen; ii) develop and validate a stability-indicating analytical method to quantify LM22A-4 and separate the compound from its degradation products; iii) develop and characterise PLGA microparticles with and without the drug (i.e., ibuprofen or LM22A-4).
Methods: A novel stability-indicating High-Performance Liquid Chromatography (HPLC) method was developed and validated to evaluate the stability of LM22A-4 before loading the drug into the polymeric formulation. W1/O/W2 double emulsion solvent evaporation method was used to fabricate PLGA microparticles and encapsulate LM22A-4. The components employed in formulation development were assessed using pre-formulation characterisation experiments. Both PLGA microparticle formulations with and without drugs were then characterised for particle size, drug loading (DL, %), encapsulation efficiency (EE, %), drug-polymer interaction, thermal properties, and in vitro drug release from PLGA microparticles. Ibuprofen sodium salt was used as a model drug of LM22A-4 before transitioning to LM22A-4.
Findings: Using the developed and validated HPLC method for LM22A-4, LM22A-4 found to be not stable under hydrolytic and photolytic stressed conditions while stable under oxidative and thermal stressors.
Optimised PLGA microparticles showed particle size between 5 and 70 μm, and the polymeric formation did not alter either PLGA of the payload’s chemical structure or thermal properties. Drug-loaded PLGA microparticles had relatively low DL (ibuprofen-loaded, 2.38 %; LM22A-4-loaded, 0.32 %) and low EE (ibuprofen-loaded, 25.66 %; LM22A-4-loaded, 29 %). LM22A-4-loaded formulations exhibited a burst of release followed by a plateau, with complete release not achieved, whereas ibuprofen-loaded PLGA microparticles displayed initial burst drug release profile with most drugs released over two days.
Conclusion: These results indicated the promise of using PLGA as a drug carrier. However, further study is needed to reduce the burst release and achieve sustained release of the entire drug payload with improved DL and EE
Associated factors, barriers, and interventions to promote physical activity and reduce sedentary time in academics: a systematic review
No full textBACKGROUND: Low physical activity and prolonged sedentary time harm health and psychological well-being. Being insufficiently active is associated with a risk of numerous non-communicable diseases, including cardiovascular disease, hypertension, and diabetes. Academics comprise a notable portion of the workforce and serve as important role models, yet their positions may involve many sedentary behaviours. The factors associated with their physical activity and sedentary behaviours are unclear. This review aimed to identify the associated factors, barriers, and the effectiveness of interventions in promoting physical activity among academics. METHODS: Systematic review. The data were collated from CINAHL Ultimate, Cochrane, Medline (OVID), Scopus, and SPORTDiscus between March and April 2024. Studies were selected if they (1) involved participants employed in academics, including professional staff (2), investigated the physical activity or sedentary behaviours as a primary outcome and/or the associated factors, and (3) identified the effectiveness of physical activity interventions. Studies with full-text in English were selected if published in peer-reviewed journals before April 2024. RESULTS: Of the included 46 studies,12 demonstrated 63.10% (95% CI [54.70%, 71.10%], p < 0.0001, I2 = 96.40%) of participants had low physical activity, while 2 reported a long mean sedentary time per workday of 553.10 min (95% CI [29.51, 1135.72], p = 0.70 I2 = 0%). Various physical activity measures were utilised, and 42 associated factors were identified, categorised as sociodemographic (n = 7), psychological (n = 13), environmental (n = 6), work-related (n = 7), and health-related factors (n = 9). Sedentary behaviours were associated with burnout, lower prospective mood, and lower energetic arousal. Barriers to physical activity (n = 12) and interventions (n = 7) were identified. CONCLUSIONS: The findings suggest that it is imperative to develop institutional strategies and interventions to promote physical activity in the academic population. The diversity and complexity of factors associated with physical activity indicate that further research with a large sample size and a consistent measure is needed to identify the needs of academics for physical activity promotion to enhance well-being. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-025-24092-2
Development of a Dual-Modality Photoacoustic and Ultrasound Vector-Flow System: Towards Quantification of Haemodynamic Parameters in Soft-Tissue and Bone Models
No full textThere is no gold-standard clinical technique to quantify the speed and direction of blood flow within cortical bone, despite its potential to provide valuable insights into bone health. Ultrasound and photoacoustic imaging are promising modalities as they offer greater imaging depths compared to purely optical techniques, while also being innately non-invasive and without the use of ionising radiation.
In this thesis, we develop a dual-modality ultrasonic and photoacoustic vector-flow system for imaging flow within soft tissue and bone models. Both vector-flow modalities quantify the velocity of moving particles at each pixel from a series of images reconstructed using multiple subapertures. We use a least-squares approach to estimate the velocity vectors in the overdetermined ultrasonic and photoacoustic Doppler equations.
First, these techniques are validated in a soft-tissue phantom with whole rat blood flowing in the range of ~mm/s. Unlike ultrasound vector flow, motion is detected without clutter filtering using photoacoustic vector flow.
Subsequently, we extend our soft-tissue technique to bone models. In clinical ultrasound imaging, the speed of sound is assumed to be homogeneous. This is not valid for imaging bone, which has a significantly faster speed of sound than soft tissue, resulting in refraction. We present a method that accurately computes photoacoustic and ultrasonic vector flow by accounting for refraction by bone in the image reconstruction. We compare this technique against conventional delay-and-sum for both photoacoustic and ultrasound vector flow in acrylic phantoms to mimic bone with a blood-mimicking fluid flowing at ~4 mm/s. Refraction-corrected reconstruction improves flow speed and direction estimates for both imaging modalities.
Finally, we present a novel method for isolating overlapping flow in multiple directions. Most of the blood vessels in cortical bone are too small to resolve with photoacoustic and ultrasound imaging, so a single pixel will contain flow in multiple directions. We propose a method to transform ultrasound images into the frequency-lateral wavenumber domain to identify and isolate unique flow components. We explore this approach in data acquired from a microfluidic flow phantom and in a Doppler string phantom, augmented to generate multiple flow directions in the images
Modulation of the lens water content changes the stiffness of the ex-vivo non-decapsulated bovine lenses
No full textPurposeTo determine whether modulation of lens water content can alter the stiffness of the ex vivo bovine lens which have a similar stiffness profile to the presbyopic human lens.MethodsBovine lenses cultured in isotonic artificial aqueous humor (AAH) were initially subjected to either MRI imaging using a clinical 3T scanner or a spin test to obtain baseline measurements of water content and shear modulus, respectively. Lenses were then exposed to either hypotonic or hypertonic stress to swell or shrink lenses, respectively, or isotonic AAH + ouabain or high extracellular potassium (AAH-High-K+) to inhibit lens water transport, for up to 4 hours before repeating the MRI scans and spin test.ResultsIn isotonic AAH both free and total water was higher in the outer cortex of the lens relative the central lens nuclear region, but the shear modulus profile had the opposite profile being highest in the lens nucleus. Exposure to hypertonic AAH that shrinks the lens caused a loss of lens water and an increase in the shear modulus in the lens nucleus that served to steepen the shear modulus profile. In contrast, exposure to hypotonic-AAH to sweel the lens increased both free and total water content through all regions of the lens and caused a reversal of the shear modulus so that the nucleus of the lens became less stiff than the outer cortex. These effects of osmotic stress on the shear modulus profile were partially reversed upon the return of lenses to isotonic AAH. Inhibiting lens water transport under isotonic conditions caused more subtle increases in lens water content than seen with hypotonic challenge but still cause a similar softening of the nucleus but had no major effect on the shear modulus in the outer cortex of the bovine lens.ConclusionsOur results demonstrate a link between lens water content and the stiffness of the nucleus of the bovine lens. This suggests that the modulation of lens water transport represents a novel strategy for the development of pharmacological interventions designed to restore accommodation in presbyopes by softening of the nucleus of the human lens
Technological advances in the diagnosis and management of inherited optic neuropathies
No full textPreferential degeneration of retinal ganglion cells (RGCs) is a defining feature of the inherited optic neuropathies (IONs), a group of monogenic eye diseases predominately comprising Leber hereditary optic neuropathy (LHON) and autosomal dominant optic atrophy (DOA). Their pathogenesis is characterised by mitochondrial dysfunction, which causes loss of RGCs leading to irreversible vision loss. Although currently incurable, there are several emerging therapeutic avenues encompassing gene therapies, precision medicine strategies and neuroprotection. These are underscored by recent technological advances such as next-generation sequencing and improved disease modelling. In this review, we discuss these advances and the impact these will have on future diagnostic and treatment capabilities. We first focus on the clinical presentation and pathogenic mechanisms of LHON and DOA, followed by a discussion of emerging technology to facilitate diagnosis and treatment. We highlight the current unmet clinical demand of IONs, and the promise of current and future research developments
An analysis of e-cigarette policy action, inaction and industry influence: Implications for youth uptake in New Zealand
No full textA Vibliometric Analysis of Impulse Buying
No full textImpulse buying is defined as a sudden and immediate purchase with no pre-shopping
intentions either to buy the specific product or to fulfill a specific buying task. This project is
a literature review paper executed through a bibliometric analysis using VOSviewer to study the
potential areas of research that have been majorly left untapped by researchers so far.The
knowledge base for the source on research papers regarding impulse buying was taken from
Scopus. The Bibliometric Map was achieved successfully and further mapping helped I finding
that the areas of research regaring Impulse Buying that does have a lot of potential and should be
explored includes: Brand, Campaign,Consumer, Electronic Commerce, Groups, Marketing,
Methods, Product,Retail Commerce and Adolescents