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Gender Tapestry: gender classification as color assignation
No full textGender Tapestry is a multi-stage interactive AI art project, challenging traditional gender classification systems. This project diverges from binary approaches by recognizing the individuality of the gender experience and expression. This paper draws parallels to the ways color perception differs amongst people and how gender is also experienced in different ways due to lived experiences. Gender Tapestry uses a multi-label classification system, with predictions extending across six gender categories, with a custom RGB color generated based on the outcomes. Participants receive binary images of their face in their personalized colors and styles, while their uploaded photos contribute to a live Generative Adversarial Network training process. This work was created in response to the very binary representations of gender in AI and the lack of representation for genders outside of the binary. The culmination is an evolving mosaic artwork, incorporating all users' custom colors, illustrating gender as a fluid construct. The mosaic gains in complexity as more images are added and more colors enter the mix, creating a community artwork on gender as a 3D color spectrum. This work contributes to the discourse on diversity and inclusion in AI, emphasizing the fluidity of gender and fostering unconventional artistic representations.</p
The deals before the deals: how platforms are leveraging existing relationships with publishers to avoid regulation
No full textThe report indicates a systemic need for a human-centered journalism industry. Whether it is calling for more, equity, inclusion, and diversity in boardrooms and newsrooms; favoring a diversified media ecosystem over monopolies and authoritative regimes; or calling for ownership and funding models that focus on providing valuable civic information for the sake of a healthy democracy, the authors repeatedly identified the possible perils of maintaining the current status quo in journalism.</p
Valorization of Commercially Important Essential Oils of Poaceae and Lamiaceae Families Using Heterogeneous Catalysts
No full textThis work offers a comprehensive exploration of innovative catalytic processes designed to transform essential oil components, addressing challenges related to unwanted compounds and enhancing the value of traditionally undervalued essential oils. Each section of this thesis introduces distinct catalytic transformations, showcasing applications that span the fragrance, pharmaceutical, and chemical industries.Mitigating the challenge posed by pulegone, a carcinogenic compound in dementholized oil (DMO) during menthol crystal separation, involves the introduction of two novel catalysts: 3%Pd-2.5%Al- 1.5%B/AC and 2%Pd-3%Si/AC. These catalysts facilitate the selective conversion of pulegone to thymol and menthone/isomenthone, with optimized conditions yielding impressive results (98.54% for thymol and 97.68% for menthone/isomenthone). This approach extends to pulegone-rich essential oil (CIM-Vishisth variety), demonstrating efficacy in reducing pulegone content for commercial use. Targeting the transformation of citral, a major component in lemongrass essential oil (low value essential oil), and the present work introduces a novel catalytic process with a 12%Ni-HT-530 composite. This process exhibits remarkable efficiency, achieving a 99% conversion and 95% selectivity for enantiospecific (+)-citronellal. The adaptability of this process is further showcased in lemongrass oil, highlighting its potential for industrial applications. In another scheme, the selective hydrogenation of citral to nerol and geraniol is achieved using a modified Fe2O3 catalyst, 3%Ni-1.5%Pd/Fe2O3. Synthesized through various methods, the catalyst demonstrates high selectivity (97%) under optimized conditions, offering a viable route for transforming citral in lemongrass essential oil into valuable sweet smelling (nerol/geraniol) rosy note products. Describing a two-step catalytic process for the semi-synthesis of (-)-menthol from citronellal-rich essential oils, bi-acidic composites (Al-B-NaYZE or Sn-B-NaYZE) play a crucial role. These composites exhibit high selectivity (99%) for the cyclization of citronellal to isopulegol isomers. The subsequent reduction to menthol using 1%Pd/AC demonstrates efficient biobased menthol production. The spent oil after menthol separation has displayed antimicrobial activities; hence, it is used in the preparation of health-care products. In another scheme, a green process has been developed for the semi-synthesis of p-menthane-3,8-diol (PMD), a mosquito repellent, from citronellal-rich essential oils. Metal-incorporated Sulfonated biochar (SBC) catalysts (Zn, Cr, Fe & Ni) prepared via a hydrothermal process demonstrate high efficiency and selectivity. The Cr-SBC-HT catalyst achieves exceptional results, with 99% citronellal conversion and 96% PMD selectivity. This compound has displayed mosquito repellency up to 6 hours, and very closely compared with DEET (N,N-diethyl-m-toluamide).Further, the bio-nano-technological synthesis of silver (Ag) and silver-copper (Ag-Cu) nanoparticles utilizing the discarded aqueous portion of Prosopis cineraria pod were used for monoterpenes epoxidations. These synthesized nanoparticles exhibit antimicrobial properties and find application in the epoxidation of alkene moieties, showcasing their potential in nano-medicine, therapeutics, and the modification of monoterpenoids for fine fragrance. Collectively, these contributions significantly advance the development of environmentally friendly and economically viable catalytic processes, offering widespread applications across diverse industries. The major advantages of novel catalytic processes include enantiospecific product selectivity, reusability, quick attainment of reaction pressure and temperature, and the production of a final product that is 100% biobased. Consequently, the finished product is considered as nature-identical. Therefore, catalytic modification of essential oil to commodity products might be suitable for commercial applications, serving the fragrance, flavor, and pharmaceutical industries.</p
Mosquito-borne Murray Valley encephalitis: Re-emergence in Western Australia
No full textMurray Valley encephalitis virus (MVEV) is a zoonotic flavivirus, transmitted by Culex annulirostris mosquitoes, and is endemic in Northern Australia and Papua New Guinea with sporadic outbreaks occurring. Occasionally cases occur in south-eastern Australia. MVEV was first identified in 1917 in the South-eastern region of Australia along the Murray River which crosses 3 states (Victoria, New South Wales, and South Australia). Following heavy rainfall and flooding during the summer season, Murray River, Australia's longest river, experienced surges in MVEV cases, leading to local endemicity. As such, major MVEV outbreaks in south-eastern states of Australia include 45 cases in 1951, 58 cases in 1974 and 17 cases in 2011 with cases in intervening years predominantly restricted to Northern Australia. During the Australian summer of 2022–2023, 26 human cases were reported, attributed to a surge in mosquito populations and water birds following prolonged flooding events. Ciconiiformes water birds, such as cormorants and herons, serve as hosts in the bird-mosquito-bird cycle, with transmission to humans occurring through infected mosquitoes. In humans, infection with MVEV results in an illness known as 'Australian X′ characterised by symptoms of fever, headache, nausea, stiff neck, and light sensitivity. However, severe cases can manifest with confusion, seizures, paralysis encephalitis, and even death.</p
Physical activity and depression symptoms in people with osteoarthritis-related pain: A cross-sectional study
No full textOsteoarthritis is a leading cause of chronic pain and is associated with high rates of depression. Physical activity reduces depression symptoms and pain levels. It remains unknown if physical activity is associated with lower symptoms of depression irrespective of pain levels in individuals with osteoarthritis. We explored whether pain mediated or moderated the relationship between levels of physical activity engagement and depression symptoms. Individuals with osteoarthritis who were waiting for an orthopaedic consultation at a public hospital in Melbourne, Australia, were recruited. Data collected on pain levels, physical activity engagement and depression symptoms. Descriptive statistics were used to summarise participant characteristics. Moderation and mediation analyses were used to establish the impact of pain on the relationship between physical activity and depression, after adjusting for demographic and joint specific characteristics. The results indicated that the inverse association between physical activity and depression depended on the level of pain, such that the association was stronger in people with greater pain. The mediation results confirm that participating in physical activity is indirectly, inversely associated with symptoms of depression through lower levels of pain. The highest levels of pain were associated with the most potential benefit in terms of reduction in symptoms of depression from engaging in physical activity. Physical activity may be particularly important to manage depression symptoms in people with greater osteoarthritis-related pain as patients with the highest pain may have the greatest benefits.</p
Biomarker role of maternal soluble human leukocyte antigen G in pre‐eclampsia: A meta‐analysis
No full textINTRODUCTION: Human leukocyte antigen-G (HLA-G) is a non-classical class I HLA molecule shown to regulate the immunomodulation of maternal immune cells to prevent fetal tissue destruction. Low levels of freely circulating maternal soluble HLA-G (sHLA-G) have been observed in pre-eclampsia, however, no pooled evidence exists. This meta-analysis aimed to generate pooled findings on the association of sHLA-G levels with pre-eclampsia and is the first study to perform a trimester-wise comparison of the levels of sHLA-G in preeclamptic cases and normal pregnant controls. METHODS: The databases PubMed, Emba, Web of Science, and Google Scholar through May 31, 2023. Preeclamptic women were defined as cases and normal pregnancies as controls. Data on the level of sHLA-G in cases and controls was extracted and subjected to a meta-analysis using a random-effects model. The pooled effect was expressed in terms of standardized mean difference (SMD). Sensitivity analysis was performed to investigate the effect of the exclusion of each study on the pooled results. Publication bias was assessed statistically. RESULTS: Nine studies with altogether 567 PE cases and 1132 normal pregnancy controls were included in the meta-analysis. The first and third trimester levels of sHLA-G in PE cases were significantly lower than that of normal pregnant controls: (SMD: −0.84 [−1.29; −0.38]; p = .003; I2 = 54%) and (SMD: −0.39 [−0.71; −0.06]; p = .02; I2 = 79%) respectively. Sensitivity analysis revealed significant fluctuations in the pooled findings when few studies were excluded, raising questions on the consistency of results among studies.CONCLUSION: Although we found that first and third-trimester sHLA-G levels in pre-eclampsia are significantly lower, taking into consideration the inconsistent results from the sensitivity analysis, our findings advocate the demand for more studies with larger sample sizes to generate solid ground pooled evidence on the predictive role of sHLA-G in pre-eclampsia.</p
Reviving Fertility: Phytochemicals as Natural Allies in the Fight against Non-genetic Male Infertility
No full textBackground Male infertility poses a growing challenge to the healthcare system, with its prevalence on the rise. Unhealthy lifestyle, food, and addictions such as smoking, alcoholism, etc. accelerate the occurrence. While several approaches are being investigated to prevent and treat this condition, each therapeutic approach has its drawbacks. Traditional medications continue to play a crucial role in the healthcare system. In recent years, there has been a shift towards determining the efficacy of phytochemicals (or, herbal drugs) as remedies. Objective To evaluate the effect of various herbs, plant, metabolites, or a part of plant in management of non-genetic male infertility. Methods The male infertility-associated keywords were searched in PubMed, excluding those non-English writen papers. A total of 146 pertinent and closely connected records were included for full reading and inclusion in the systemic evaluation. Results The manuscript focuses on individual herbal drug components, their active ingredients, their role in improving the condition and quality of life, and decreasing the prevalence of male infertility. Conclusion Herbal medicinal plants show promising outcomes to treat male infertility. Herbal alternatives are appealing and have regained popularity. The future holds promise for some of these herbal treatments to advance with many showing improved outcomes in males with infertility issues.</p
Discovery of Novel Materials in Actuator Applications
No full textMany of the current devices that society uses daily as a necessity, rely on some form of motion. This can range from the motion in large devices such as motors in cars, to the motion in speakers present in smaller devices such as smartphones. The motion that is produced comes from actuators, which are devices that can undergo dimensional changes in response to stimuli from the environment external to the device or within the device itself. Such stimuli can include temperature, pressure, mechanical strains and electrical charges.
The materials often found in actuators are often referred to as stimuli responsive materials, making them ideal for various environmental conditions. However, as technology advances, so too will the efficiency and performance needs of these devices. To limit waste in the production process, or to reduce the dimensions of the devices, the materials required will also become smaller. Therefore, it is essential to find materials that can make up these newer devices while maintaining their functionality and providing sufficient outputs.
Materials that respond to electricity or injected charge are ideal for actuators as they are known to generate mechanical deformations that are highly accurate within the micro- and nanometre range. This includes piezoelectric materials that are able to convert electrical energy into mechanical deformations and vice versa.
In this thesis, the effect of external stimuli, specifically application of electric field and charge, on the structure and properties of a variety of nanomaterials will be investigated. This work focuses on using a computational approach and specifically density functional theory (DFT) calculations to screen the piezoelectric and electromechanical properties of one-dimensional (1D) and two-dimensional (2D) nanomaterials for their potential application in actuator devices. Other applications, namely as gas sensing materials is also explored.
The nanomaterials studied in this work include ultra-thin 2D zinc oxide (ZnO), 1D black phosphorus (BP) nanotubes, and the 2D monolayer and bilayer group-IV monochalcogenides (germanium sulfide (GeS), germanium selenide (GeSe), tin sulfide (SnS) and tin selenide (SnSe)) as they all have either outstanding piezoelectric or structural properties suitable for actuator devices.
ZnO is known to be a highly piezoelectric material, producing the largest piezoelectric responses among tetrahedrally bonded semiconductors. With its non-centrosymmetric buckled structure and distinct polar surfaces, ZnO is the ideal material for piezoelectric based applications. However, when reduced to fewer than 8 atomic layers thick, 2D ZnO sheets become planar similar to a sheet of graphene, and as a result lose their piezoelectric properties. In this thesis it is shown that by introducing defects to the system, the centrosymmetric structure of graphitic ZnO nanosheets can be broken, restoring their polarity. In particular, it was determined that Zn vacancies can not only restore the piezoelectric properties of ZnO nanosheets but can produce piezoelectric responses that exceed the bulk value by 120%.
The group-IV monochalcogenides are both highly piezoelectric and flexible due to their similar structure with BP and non-centrosymmetric structure. Having a puckered orthorhombic structure allows them to undergo high strains making them ideal for actuator applications. It is not known, however, how their 2D monolayers respond to charge injection. All 4 monolayers can achieve enhanced strain responses after hole or charge injection, with monolayer SnS achieving an electromechanical strain response up to -12.7% greater by contracting. The volumetric work density and actuation stress produced by these materials upon charge injection means they could be ideal for nano-based actuators.
As the group-IV monochalcogenides exist as layered materials, they can be synthesized as bilayers. By stacking two layers of the same material or two different materials, bilayers could yield properties that are not seen in either the bulk or monolayer counterparts. In this work, the piezoelectric response for different stacking arrangements were investigated. Overall, bilayer SnSe was calculated to have a 130% increase in the piezoelectric response compared to the monolayer.
BP monolayers are known to have outstanding strain responses due to their puckered orthorhombic structure. The flexibility offered by BP allows it to easily deform in the presence of external stimuli, with charge injection causing the monolayer to expand significantly. However, it is not known how their 1D counterpart, nanotubes, will respond to the injected charge. In this work, the electromechanical response of BP nanotubes comprised of 4 different diameters are examined. It was shown that a NT with 15 BP units can expand in diameter up to 30.2%, a value which is larger than other 1D nanomaterials, such as carbon and molybdenum disulfide nanotubes. Hence the expansion in diameter enables further applications for the material in drug delivery and nanochannel applications.
In addition to the potential applications in piezoelectric and electromechanical actuators, 2D nanomaterials are ideal candidate materials for gas sensing devices due to their high surface area. The sensitivity of monolayer group-IV monochalcogenides to toxic gases, including NH3, NO2 and SO2 was determined using DFT calculations. For a 0.25 ML coverage, the reducing gas, NH3, was physisorbed on the monolayer and acted as an electron donor. The sensitivity to the oxidising gases, NO2 and SO2 were significantly stronger, with both gases withdrawing electrons from the monolayers. However, the binding of the gases to the monolayers was shown to be controllable with an applied electric field. An electric field of -0.8 eV/Å changes the adsorption type of NH3 from being physisorbed to weakly chemisorbed with the direction of charge transfer reversing so the gas withdraws charge from the monolayers. The sensitivity of NO2 was greatly enhanced with a +0.8 eV/Å electric field making the gas strongly chemisorbed on the monolayers. Similarly, the sensitivity to SO2 was also increased but to a lesser extent.
To summarise, nanomaterials that are highly piezoelectric and flexible are promising candidates for actuator-based devices as they can generate sufficient strain responses to produce accurate displacements in a large range. Furthermore, the strain responses of monolayer group-IV monochalcogenides can be used to enhance the storage and sensing ability of these materials to pollutant gases. The results presented in this thesis have provided an insight into the possible candidate materials for piezoelectric and electromechanical actuator devices.</p
The Cardiovascular Consequences of Influenza A Virus Infection: Mechanisms and Therapies for High-risk Groups
No full textInfluenza (IAV) is a significant global respiratory virus, responsible for 1 billion infections every year. Although infection in healthy individuals is often self-limiting, in high-risk populations, such as pregnant women and those with underlying cardiovascular disease (CVD), influenza poses a significant health concern. Clinically, pregnant women have an elevated risk of preterm birth, intrauterine growth restriction (IUGR) and miscarriage, while the long-term effects of maternal infection have been associated with neurodevelopmental disorders in children, such as autism and schizophrenia. Preclinical models have shown that IAV infection during pregnancy results in a ‘vascular storm’, with viral dissemination into the cardiovascular system triggering significant endothelial dysfunction and inflammation. Aspirin is a currently approved therapeutic for use in pregnancy to treat preeclampsia (PE), a hypertensive disease of pregnancy, and therefore may lend itself to use during maternal IAV infection. Similarly, in people with underlying cardiovascular disease, such as those with atherosclerosis, infection has been linked with adverse vascular outcomes, however the mechanisms are not well understood. Atherosclerosis is a chronic inflammatory disorder characterised by the development of atherosclerotic lesions throughout major blood vessels which contribute to arterial stiffening and reductions in blood flow. In people with atherosclerosis, infection has been linked with plaque destabilisation and myocardial infarction. Despite vaccination significantly reducing the incidence of these adverse events, vaccination uptake remains low.
Throughout this thesis, we investigated the cardiovascular consequences of IAV infection in high-risk groups to identify the potential mechanisms underpinning adverse outcomes as a result of infection and identify therapeutic opportunities using pre-clinical mouse models.
To begin, we hypothesised that currently approved therapeutic aspirin (ASA) and its novel nitric oxide derivative NCX4016 (NCX) would promote cardiovascular health in pregnant IAV infected dams. Accordingly, IAV infection caused local lung inflammation, with viral dissemination into the maternal aorta resulting in the ‘vascular storm’, with significant aortic inflammation and endothelial dysfunction. Treatment with either ASA or NCX significantly reduced viral dissemination into the maternal cardiovascular system, with reduced aortic inflammation and improved endothelial function. Further, we found that treatment with either ASA or NCX promoted the development of the pregnancy and improved survival rates of pups born to IAV infected dams.
Upon establishing that IAV has profound effects on the cardiovascular system, we decided to investigate the effects of IAV infection in models of cardiovascular disease, such as atherosclerosis. To begin, we hypothesised that influenza infection in atherosclerotic mice would cause vascular inflammation, like what we observed during IAV infection in pregnancy, and that this would result in the increased progression of atherosclerosis. Surprisingly, influenza significantly reduced atherosclerotic lesion coverage throughout the aorta. However, the functional capacity of the aorta was significant reduced, with reductions in total vascular relaxation to smooth muscle dilator, sodium nitroprusside (SNP) and the thinning of the aortic intima and media. Not only this, but infected mice showed cardiac hypertrophy and reduced natural killer cell populations, which may be indicative of the development of pulmonary hypertension.
To continue our investigations in preclinical models of atherosclerosis, we interrogated the effects of IAV on the respiratory system of atherosclerotic mice. We found that acutely, IAV infection caused local lung inflammation and bodyweight loss. Chronically, IAV infection caused significant reductions in lung functional capacity such as inspiratory capacity (IC) and FEV0.1/FVC ratios. Further, mice showed significant structural damage with increased distance between alveolar walls (Lm), and the chronic elevation in expression of cytokines TNFα, IL-6 and IL17, while there were no changes in MMP expression.
This combined work in this thesis highlights the impacts of IAV infection on the cardiovascular system in high-risk populations and shows for the first time that the vascular storm can be therapeutically targeted to protect the cardiovascular system during infection. We provide strong evidence to improve the current clinical management of patients not only in the acute phases of IAV infection, but chronically to monitor the development of future lung and cardiovascular diseases. As well, we suggest that future therapeutics for these patients should not only focus on the respiratory system but should be broadened to include combination therapies that treat subsequent cardiovascular inflammation as well.</p