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Astringent effects of red wine associated with responses of Aquaporins found in human tongue and salivary tissues
No full textAquaporin (AQP) water channels facilitate fluid transport across cell membranes, are implicated in rodent oral water sensing, and were examined in the human tongue for their modulation by mouthfeel compounds and ensuing effects on perception and saliva tribology. Immunohistochemistry demonstrated abundant AQP1 and AQP2 and moderate AQP5 in human tongue and high AQP5 in salivary gland. Trained human tasting panels evaluated astringency intensities; results correlated with wine tannin measures and inhibition of AQP1 water flux (R² ≥ 0.9). Wine tannin extract additions of 1 g/L reduced cell swelling −125 ± 20% (SE) (P < 0.0001), increased saliva-tannin friction coefficient 16.0 ± 1.9% (P < 0.0001) and astringency scores 17.3 ± 5.5% (P < 0.006). Osmotic swelling assays identified wines, red wine polyphenols, alum sulfate, and tannic acid─all archetypal astringents─as inhibitors of AQP1 and to a lesser extent AQP5. Astringent block of AQPs present in tongue and salivary gland suggests a mechanistic role of water flux in drying sensations, beyond the established changes in saliva resulting from tannin and proline-rich-protein interactions. Insights into AQPs as molecular components of mouthfeel could inform fundamental debates on how astringent phenomena arise and increase understanding of nutrient sensing and uptake as found within the digestive tract and throughout the body
Hypoxia and venous occlusion improve muscular performance but no effect on growth hormone in athletes
Get PDFIntroduction: Resistance training enhances muscle strength and size; however, high-load exercise (>85% 1RM) may increase the risk of injury. Low-load resistance training with hypoxia or blood flow restriction (BFR) offers safer alternatives, although comparative data are limited.
Objective: To examine the effects of hypoxia and BFR on resting growth hormone (GH) levels after five weeks of low-load resistance training.
Methods: Thirty male athletes (19–24 years) were assigned to three groups: RT (50% 1RM), RT + HPX (50% 1RM under hypoxia, FiO₂ = 0.137), and RT + BFR (50% 1RM with BFR). Participants performed knee extension and flexion (3 sets × 15 reps, 1-min rest) three times weekly for five weeks. Muscle thickness, strength, resting GH, and blood lactate levels were measured before and after training.
Results: After training, RT + HPX and RT + BFR showed significant increases in rectus femoris and biceps femoris thickness. Strength improved in all groups, with knee extension strength higher in the RT+HPX (30.9 ± 16.3%, p = 0.047) than RT (16.1 ± 7.3%). The resting GH levels did not differ significantly between the groups (p > 0.05). Post-exercise lactate increased significantly only in the RT+BFR (68.7 ± 57.2%, p = 0.018).
Conclusion: Low-load training with hypoxia or BFR enhances muscle hypertrophy and strength, and hypoxia produces greater strength gain. Resting GH levels appear to be unrelated to these adaptations, suggesting that further studies are needed to clarify the underlying mechanism
A theoretical investigation of the recruitment of sodium channels to the Axon Initial Segment (AIS) in neurons
Get PDFThe axon initial segment (AIS) in neurons plays a vital role in initiating action potentials, primarily due to the high density of voltage-gated sodium (Nav) channels concentrated in this region. These Nav channels contain multiple serine residues that mediate their recruitment to the AIS through interactions with ankyrin-G (AnkG). AnkG plays a pivotal role in neurogenerative diseases such as Alzheimer’s, and it is important to understand the dynamics of its interactions with other proteins. In this paper, we develop a theoretical approach to understand the roles of two AIS proteins—casein kinase 2 (CK2) and AnkG—in facilitating Nav channel recruitment to the AIS membrane by firstly modelling the CK2 phosphorylation of Nav and then the binding of AnkG to phosphorylated Nav. Given the structure of Nav, we develop a conceptual model for the mathematical models based on well-defined macro- and micro- states of Nav that participate in elementary reactions simultaneously. The results of the models are discussed in graphical manner to unravel the complexity associated with the AIS dynamics and the dependence of associated kinetic coefficients
How does carbon transition risk drive corporate diversification? Evidence from heavy emitter firms in China
Get PDFCarbon-intensive firms are increasingly exposed to carbon transition risks stemming from evolving climate policies, forcing them to adapt to a low-carbon economy. While prior research focuses on direct environmental initiatives to mitigate carbon transition risks, limited attention has been given to corporate diversification as an alternative strategy. This study investigates the impact of carbon transition risks on revenue diversification of Chinese listed firms, employing a difference-in-differences framework with the Paris Agreement as an exogenous shock. We find a significant increase in diversification of heavy-emitting firms following the Paris Agreement compared to their counterparts, without a corresponding increase in environmental investments or green technology adoption. This response is notably pronounced among firms with state ownership and is weakened when investment irreversibility is high. The findings align with the real options perspective and provide new insights into corporate responses to climate policy changes within the unique context of China
Influence of phosphate retention capacity on the potential plant availability of struvite fertiliser in acidic grassland soils
Get PDFContext. Sustainable agricultural production relies on efficient phosphorus (P) management due to the finite nature of phosphate rock reserves, increasing fertiliser costs for farmers, and environmental concerns associated with P losses. Struvite, a P fertiliser recovered from wastewater, appears to be an alternative to conventional water soluble-P fertilisers. Aims. We aimed to evaluate changes in the concentration of soil available P in response to the application of struvite in three New Zealand acidic soils with varied P retention capacities. Methods. A plant-less incubation was carried out for 63 days where struvite, two water soluble-P fertilisers, and reactive phosphate rock were applied at two rates to three contrasting soils. Key results. Regardless of soil type, struvite significantly increased Olsen-P concentrations, comparable to conventional P fertilisers. P retention capacity influenced P release patterns, with Pallic soil exhibiting the highest Olsen-P increases due to its low P retention. P release from struvite was rapid but showed sustained availability in Pallic soil compared to declines in Allophanic and Brown soils. Conclusions. Struvite showed similar fertiliser-P behaviour in soils with contrasting P retention capacity generating changes in Olsen-P like those from watersoluble P fertilisers. Implications. Further research is necessary to investigate the suitability of struvite as an alternative P fertiliser source for New Zealand agriculture
The development of sports nationalism in Taiwan 1990-2023: A study of news coverage and social media comments : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University
Get PDFWith the democratisation and political and economic liberalisation of Taiwan, “Taiwanese” has replaced “Chinese” as the predominant national self-identification. However, sports as a cultural field, which embodies nationalist ideology, has not undergone corresponding changes. For example, terms such as “Chinese Taipei”, “Chung-Hua (中華/ Chinese) athletes”, and the “Chung-Hua (中華/ Chinese) team” are still widely used, and the name rectification referendum of 2018, which proposed that national teams compete under the name Taiwan, was voted down. Thus, this study aims to examine the interrelationship of sports nationalism and nationalist transformation. The research data for this study comprised sports news articles from Taiwanese newspapers and social media posts concerning three key topics: international baseball competitions from 1990 to 2023, the name rectification referendum, and the 2020 Tokyo Olympic Games. Using the theoretical frameworks of imagined communities, invented traditions, and banal nationalism, along with thematic analysis and critical discourse analysis, this study examines these research materials to explore their underlying nationalist narratives. Thematic analysis identified themes within the texts, while critical discourse analysis was employed to investigate how content use in sports media strengthened or opposed nationalist ideologies. The findings indicate that Taiwan’s sports nationalism evolved from ethnic nationalism to the Republic of China (ROC) civic nationalism, and ultimately to Taiwanese nationalism. The findings further explain that the referendum’s defeat can be attributed to the Taiwanisation of the ROC and Chinese Taipei. Further, the findings from the analysis of the 2020 Tokyo Olympic Games indicate that sport functions as a mechanism for reaffirming Taiwan’s nation-statehood and national identity by linking the ROC’s national significance to Taiwan, thereby nationalising Taiwan. This study argues that these changes are driven by the interaction of sport, democratisation, and Taiwanisation. Theoretically, the contribution of these findings lies in offering an alternative theoretical framework to better understand the transformation of Taiwan’s sports nationalism. Methodologically, while previous studies have primarily focused on how political and cultural elites shape national identity—a top-down approach, this study addresses how the public interacts with nationalist narratives. By incorporating social media posts, this research integrates individuals and grassroots society into the analytical framework of nationalism, providing a bottom-up perspective. The findings reveal that social actors do not merely accept top-down indoctrination but actively interpret, negotiate, and even reshape nationalist narratives. This challenges the traditional view that nation-building was elite-driven by demonstrating that the public can be a driving force in redefining national identity. These findings and this approach offer broader insights into contemporary nationalism in the digital era. In conclusion, sports news articles link national significance to sporting events, athletes, and spectators, constructing a “new tradition” that demonstrates how “banal” sports narratives contribute to the formation of an “imagined community.” Overall, this study highlights the role of sport in nation-building, offering a broader perspective and deeper analysis of the development and transformation of Taiwanese nationalism
Reimagining local food access: Spatial opportunities of community gardens in Christchurch, New Zealand
No full textThe study explores strategic opportunities for improving access to and distribution of locally produced food. Food consumption in urban areas often depends on long and distant supply chains and corporate distribution points such as supermarkets. Poor integration of local urban food production is a source of food insecurity as much as an ecological, social, and infrastructural problem. It creates pressures on the supply and logistics of food distribution, challenging the resilience of the entire system, particularly in the context of sudden (e.g. earthquakes, floods, bushfires) and slow-onset disasters, such as climate change. This paper explores how strategic spatial opportunities for community-oriented, urban food production sites could make cities more resilient from a food security and social accessibility perspective. With the help of a case study—Urban Community Gardens in Christchurch (New Zealand)—and Geographic Information Systems (GIS) analysis, the paper proposes a method to examine spatial accessibility to urban community gardens and examines associated socio-demographic factors in comparison to commercial food outlets (supermarkets). The results suggest that the applied method is useful in examining the spatial accessibility of gardens within their specific demographic context. They reveal that urban community gardens in Christchurch are mainly located in more deprived areas and that walkable access to gardens is provided to about one-fifth of the city’s total population. The paper discusses the results within the context of specific spatial and demographic urban characteristics, including low density, car dependency and disaster susceptibility, and provides suggestions for further research and urban planning polic
Discovery of MRI biomarker for early Alzheimer's disease integrating regional atrophy and ventricular expansion
No full textTimely detection of neurodegeneration in Alzheimer’s disease, particularly during the early and late mild cognitive impairment stages (EMCI and LMCI, respectively), is crucial for effective clinical intervention and disease management. Despite widespread use of absolute and normalised brain or ventricular volumes as imaging biomarkers, the relative expansion of ventricles per unit of brain tissue remains underexplored. We introduce the Ventricle-to-Tissue Ratio (VTR), and intuitive biomarker capturing this ratio, and define its global (VTRG) and estimated (VTRE) forms. Through machine learning analyses, we demonstrate that VTRE robustly approximates VTRG, accurately tracks age and group related atrophic changes, and exhibits superior discriminative performance in distinguishing EMCI from LMCI when compared to alternative composite features. Moreover, explainable AI techniques confirm VTRE’s dominant and interpretable role in model predictions. Together, these findings establish VTRE as a sensitive, scalable, and clinically interpretable biomarker for early neurodegeneration, offering significant translational value for Alzheimer's disease diagnostics and research
Oil and petrol prices, inflation perceptions, and inflation expectations: Evidence from New Zealand
Get PDFI use a structural vector autoregression model to analyse the links between oil prices, petrol prices, inflation, inflation perceptions, and inflation expectations in New Zealand. Findings reveal that although inflation expectations are sensitive to shocks to oil prices, petrol prices, and inflation itself, they are considerably more sensitive to inflation perception shocks. Shocks to inflation perceptions explain 54% of the forecast error variance in inflation expectations after one quarter and 37% after 18 months. The results underscore the importance of including inflation perceptions in models seeking to account for inflation expectations and their associations with energy prices