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Blood flow restriction during self-paced aerobic intervals reduces mechanical and cardiovascular demands without modifying neuromuscular fatigue
No full textThis study examined cardiovascular, perceptual and neuromuscular fatigue characteristics during and after cycling intervals with and without blood flow restriction (BFR). Fourteen endurance cyclists/triathletes completed four 4-minute self-paced aerobic cycling intervals at the highest sustainable intensity, with and without intermittent BFR (60% of arterial occlusion pressure). Rest interval durations were six, four and four minutes, respectively. Power output, cardiovascular demands and ratings of perceived exertion (RPE) were averaged over each interval. Knee extension torque and vastus lateralis electromyography responses following electrical stimulation of the femoral nerve were recorded pre-exercise, post-interval one (+1, 2 and 4-minutes) and post-interval four (+1, 2, 4, 6 and 8-minutes). Power output during BFR intervals was lower than non-BFR (233 ± 54 vs 282 ± 60 W, p < 0.001). Oxygen uptake and heart rate during BFR intervals were lower compared to non-BFR (38.7 ± 4.5 vs 44.7 ± 6.44 mL kg−1 min−1, p < 0.001; 160 ± 14 vs 166 ± 10 bpm, p < 0.001), while RPE was not different between conditions. Compared to pre-exercise, maximal voluntary contraction torque and peak twitch torque were reduced after the first interval with further reductions following the fourth interval (p < 0.001) independent of condition (p = 0.992). Voluntary activation (twitch interpolation) did not change between timepoints (p = 0.375). Overall, intermittent BFR reduced the mechanical and cardiovascular demands of self-paced intervals without modifying RPE or knee-extensor neuromuscular characteristics. Therefore, BFR reduced the cardiovascular demands while maintaining the muscular demands associated with self-paced intervals. Self-paced BFR intervals could be used to prevent cardiovascular and perceptual demands being the limiting factor of exercise intensity, thus allowing greater physiological muscular demands compared to intervals without BFR
Does corporate social responsibility affect risk spillovers between the carbon emissions trading market and the stock market?
No full textThis paper examines the risk spillover effect between the carbon market and the stock market in China and the role of corporate social responsibility (CSR) on this effect. Employing Beijing, Hubei, and Guangdong carbon markets, we apply time-domain and frequency-domain spillover approaches and find that during the Chinese stock market crisis in 2015, risk spillovers from the stock market to the carbon market were more pronounced. Additionally, CSR firms are more dominant as information transmitters than those non-CSR (NCSR) firms in the carbon market. However, plausibly, due to the infancy of carbon trading, our results show that the level of connectedness between the carbon market and the stock market in China is relatively low
Continuous but not pulsed low-dose fetal betamethasone exposures extend the durability of antenatal steroid therapy
No full textAntenatal steroid (ANS) therapy is the standard care for women at imminent risk of preterm labor. Despite extensive and long-standing use, 40%–50% of babies exposed antenatally to steroids do not derive benefit; remaining undelivered 7 days or more after ANS treatment is associated with a lack of treatment benefit and increased risk of harm. We used a pregnant sheep model to evaluate the impact of continuous versus pulsed ANS treatments on fetal lung maturation at an extended, 8-day treatment to delivery interval. Continuous low-dose ANS treatments for more than 72 h in duration improved fetal lung maturation at 8 days after treatment initiation. If fetal ANS exposure was interrupted, the beneficial ANS effect was lost. Truncated treatments, including that simulating the current clinical treatment regimen, did not improve lung function. Variable fetal lung maturation was correlated to the amount of saturated phosphatidylcholine present in the lung fluid. These data demonstrate that 1) the durability of ANS therapy may be enhanced by employing an extended, low-dose treatment regimen by reducing total dose and 2) interrupting the continuity of fetal exposure by allowing it to fall below a minimal threshold was associated with comparably poor functional maturation of the preterm ovine lung
Effects of formulation on the palatability and efficacy of In-Feed Praziquantel medications for Marine Finfish Aquaculture
Get PDFPraziquantel (PZQ) provides an effective treatment against monogenean parasitic infestations in finfish. However, its use as an in-feed treatment is challenging due to palatability issues. In this study, five formulations of PZQ beads (1–4 mm) were developed using marine-based polymers, with allicin added as a flavouring agent. All formulations attained PZQ loading rates ≥74% w/w, and the beads were successfully incorporated into fish feed pellets at an active dietary inclusion level of 10 g/kg. When tested for palatability and digestibility in small yellowtail kingfish, the PZQ-loaded beads produced with alginate-chitosan, alginate-Cremophor® RH40, and agar as carriers resulted in high consumption rates of 99–100% with no digesta or evidence of beads in the gastrointestinal tract (GIT) of fish fed with diets containing either formulation. Two formulations produced using chitosan-based carriers resulted in lower consumption rates of 68–75%, with undigested and partly digested beads found in the fish GIT 3 h post feeding. The PZQ-loaded alginate-chitosan and agar beads also showed good palatability in large (≥2 kg) yellowtail kingfish infected with gill parasites and were efficacious in removing the parasites from the fish, achieving >90% reduction in mean abundance relative to control fish (p 90% compared with baseline levels. Overall, the palatability, efficacy and stability data collected from this study suggest that these two PZQ particulate formulations have potential applications as in-feed anti-parasitic medications for the yellowtail kingfish farming industry
GEOexplorer: a webserver for gene expression analysis and visualisation
Get PDFGene Expression Omnibus (GEO) is a database repository hosting a substantial proportion of publicly available high throughput gene expression data. Gene expression analysis is a powerful tool to gain insight into the mechanisms and processes underlying the biological and phenotypic differences between sample groups. Despite the wide availability of gene expression datasets, their access, analysis, and integration are not trivial and require specific expertise and programming proficiency. We developed the GEOexplorer webserver to allow scientists to access, integrate and analyse gene expression datasets without requiring programming proficiency. Via its user-friendly graphic interface, users can easily apply GEOexplorer to perform interactive and reproducible gene expression analysis of microarray and RNA-seq datasets, while producing a wealth of interactive visualisations to facilitate data exploration and interpretation, and generating a range of publication ready figures. The webserver allows users to search and retrieve datasets from GEO as well as to upload user-generated data and combine and harmonise two datasets to perform joint analyses. GEOexplorer, available at https://geoexplorer.rosalind.kcl.ac.uk, provides a solution for performing interactive and reproducible analyses of microarray and RNA-seq gene expression data, empowering life scientists to perform exploratory data analysis and differential gene expression analysis on-the-fly without informatics proficiency
Heat Stress-Mediated constraints in Maize (Zea mays) production: Challenges and solutions
Get PDFAn increase in temperature and extreme heat stress is responsible for the global reduction in maize yield. Heat stress affects the integrity of the plasma membrane functioning of mitochondria and chloroplast, which further results in the over-accumulation of reactive oxygen species. The activation of a signal cascade subsequently induces the transcription of heat shock proteins. The denaturation and accumulation of misfolded or unfolded proteins generate cell toxicity, leading to death. Therefore, developing maize cultivars with significant heat tolerance is urgently required. Despite the explored molecular mechanism underlying heat stress response in some plant species, the precise genetic engineering of maize is required to develop high heat-tolerant varieties. Several agronomic management practices, such as soil and nutrient management, plantation rate, timing, crop rotation, and irrigation, are beneficial along with the advanced molecular strategies to counter the elevated heat stress experienced by maize. This review summarizes heat stress sensing, induction of signaling cascade, symptoms, heat stress-related genes, the molecular feature of maize response, and approaches used in developing heat-tolerant maize varieties
Effect of physical activity during COVID-19 on the sleep health of community-level athletes in Australia
Get PDFThe COVID-19 outbreak presents a serious health challenges, with Australia enforcing tight restrictions, impacting sporting activities and sleep health of many Australians. Routine lifestyle patterns (physical activity and employment) are important to maintaining overall sleep health. Current literature indicates COVID-19 pandemic negatively affected the employment status and sport engagement. The aim of this study was to explore the effect of physical activity during COVID-19 on sleep health, and its association with employment and sport engagement of community-level athletes throughout Australia. Participants self-reported sleep health prior to COVID-19 (pre-sleep) and over the month prior to data collection (during-sleep) using the validated 5-item Satisfaction Alertness Timing Efficiency and Duration questionnaire (SATED). Wilcoxon Signed Rank Test assessed the difference in pre- and during perceived sleep health scores. A generalized linear model was used to assess the impact of sporting and demographic factors on a community athlete’s change in perceived sleep health score. A total of 139 community-level Australian athletes responded. The majority of participants were aged 18–30 and engaged in full-time employment prior to COVID-19 (n = 82, 54%). Eight percent of participants were unemployed prior to the COVID-19 pandemic (n = 12, 8%). Our findings show that sleep health values were higher during COVID-19, with 91.4% of respondents able to maintain some form of physical activity during the pandemic. Together, our results show better sleep health scores reported by the respondents who maintained or lost employment and maintained sporting engagements during the pandemic
Revision of the new Australasian orb-weaving spider genus Salsa (Araneae, Araneidae)
Get PDFA new Australasian genus in the orb-weaving spider family Araneidae Clerck, 1757 is described to include seven species: Salsa fuliginata (L. Koch, 1871) comb. nov. (type species; = Epeira rubicundula Keyserling, 1887) syn. nov.) (Australia, introduced to New Zealand); S. brisbanae (L. Koch, 1867) comb. nov. (Australia); S. canalae (Berland, 1924) comb. nov. (New Caledonia); S. neneba sp. nov. (Papua New Guinea); S. recherchensis (Main, 1954) comb. nov. (Australia); S. rueda sp. nov. (Australia); and S. tartara sp. nov. (Australia; Lord Howe Island endemic). Salsa gen. nov. belongs to the Australasian informal backobourkiine clade and differs from other genera of this clade by a distinct abdominal shape (single posterior abdominal tubercle) and ventral colouration (pale lateral spindle-shaped bands), male pedipalp morphology (C-shaped median apophysis that has teeth-like tubercles inside the basal arch) and the shape of the female epigyne scape (partially translucent and generally shorter than the epigyne plate). Based mainly on male pedipalp morphology within the backobourkiines, Salsa gen. nov. has closest morphological affinities with Acroaspis Karsch, 1878 and Socca Framenau, Castanheira & Vink, 2022
Interleukin-17A is associated with flow-mediated dilation and interleukin-4 with carotid plaque in persons with HIV
No full textObjective:
Chronic inflammation contributes to the high burden of cardiovascular disease (CVD) in persons with HIV (PWH). HIV has broad effects on innate and adaptive immune cells, including innate lymphoid cells (ILCs) and CD4+ T-helper cells. At present, the relationship between CVD and plasma cytokines reflecting ILC/T-helper responses in PWH is not well defined. We investigated relationships between plasma cytokines and subclinical atherosclerosis.
Design:
A cross-sectional study.
Methods:
We recruited 70 PWH on a single antiretroviral regimen (efavirenz, teno- fovir, and emtricitabine) with at least 12 months of suppressed viremia and 30 HIVnegative controls. We quantified plasma cytokines and chemokines, including inter- feron-g, interleukin (IL)-4, IL-13, and IL-17A, markers of macrophage activation, and markers of endothelial activation using multiplex assays and ELISA. Cytokines were grouped using Ward's hierarchical clustering. Brachial artery flow-mediated dilation (FMD) and carotid plaque burden were determined using ultrasound. Multivariable linear regression and negative binomial regression analyses were used to assess the relationships of plasma biomarkers and endpoints adjusted for CVD risk factors.
Results:
We identified three distinct clusters in PWH, one containing Th1/Th2/ILC1/ ILC2 type cytokines, one with Th17/ILC3/macrophage-related cytokines, and a less specific third cluster. Lower FMD was associated with higher plasma IL-17A and macrophage inflammatory protein-1 a. In contrast, IL-4, a Th2/ILC2 type cytokine, was associated with carotid plaque. When HIV-negative controls were added to the models clustering was more diffuse, and these associations were attenuated or absent.
Conclusion:
Th17/ILC3 and Th2/ILC2-mediated immune mechanisms may have distinct roles in endothelial dysfunction and atherosclerotic plaque formation, respectively, in PWH
Boron-mediated aluminium stress tolerance under aluminium toxicity at germination and early seedling stages of wheat
Get PDFAluminium stress is one of the major problems of wheat production that significantly reduces the growth and development. Al toxicity can be recovered by exogenous application of different growth inducing nutrient elements. Thus, this study was conducted to evaluate the ameliaration effect of B under Al toxicity. Therefore, a petri dish and hydroponic culture experiment of wheat was conducted at Crop Physiology Laboratory, Department of Crop Botany, Bangladesh Agricultural University, Mymensingh during the period from January 2016 to February 2017 to investigate the effect of boron on amelioration of aluminium toxicity in germination and seedling stage. Both the experiments were designed in completely randomized design (CRD) with three replications. The experiments were comprised of four levels of boron and aluminium concentrations viz., 0 µM B + 0 µM Al (control), 0 µM Al + 40 µM B, 200 µM Al + 40 µM B and 0 µM B + 200 µM Al and five wheat varieties viz; BARI Gom-23, BARI Gom-24, BARI Gom-28, BARI Gom-27 and BARI Gom-30. Results indicated that germination percentage, radicle and plumule length, root and shoot length, leaf length, fresh and dry mass plant-1 were greater in 0 µM Al + 40 µM B treated plants than 0 µM B + 200 µM Al induced conditions. It indicates that wheat seedlings are susceptible to aluminium and boron can ameliorate aluminium toxicity. However, among the studied varieties, the reduction of dry mass under aluminium stress was minimum in BARI Gom-28 followed by BARI Gom-23 indicating BARI Gom-28 was more tolerant to aluminium stress than the other varieties. On the contrary, the varieties, BARI Gom-27 and BARI Gom-24 were more susceptible to aluminium stress. So it indicates that aluminium stress severely affects the growth and developments especially in the sensitive varieties and tolerant varieties have the self-ability to grow and develop even under aluminium stress condition