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- ItemCharacterization of two conserved cell death elicitor families from the Dothideomycete fungal pathogens Dothistroma septosporum and Fulvia fulva (syn. Cladosporium fulvum)(Frontiers Media S.A., 2022-09-08) Tarallo M; McDougal RL; Chen Z; Wang Y; Bradshaw RE; Mesarich CH; Wang YDothistroma septosporum (Ds) and Fulvia fulva (Ff; previously called Cladosporium fulvum) are two closely related Dothideomycete fungal species that cause Dothistroma needle blight in pine and leaf mold in tomato, respectively. During host colonization, these pathogens secrete virulence factors termed effectors to promote infection. In the presence of corresponding host immune receptors, however, these effectors activate plant defenses, including a localized cell death response that halts pathogen growth. We identified two apoplastic effector protein families, Ecp20 and Ecp32, which are conserved between the two pathogens. The Ecp20 family has four paralogues in both species, while the Ecp32 family has four paralogues in D. septosporum and five in F. fulva. Both families have members that are highly expressed during host infection. Members of the Ecp20 family have predicted structural similarity to proteins with a β-barrel fold, including the Alt a 1 allergen from Alternaria alternata, while members of the Ecp32 family have predicted structural similarity to proteins with a β-trefoil fold, such as trypsin inhibitors and lectins. Using Agrobacterium tumefaciens-mediated transient transformation assays, each family member was assessed for its ability to trigger cell death in leaves of the non-host species Nicotiana benthamiana and N. tabacum. Using this approach, FfEcp20-2, DsEcp20-3, and FfEcp20-3 from the Ecp20 family, and all members from the Ecp32 family, except for the Ds/FfEcp32-4 pair, triggered cell death in both species. This cell death was dependent on secretion of the effectors to the apoplast. In line with recognition by an extracellular immune receptor, cell death triggered by Ds/FfEcp20-3 and FfEcp32-3 was compromised in N. benthamiana silenced for BAK1 or SOBIR1, which encode extracellular co-receptors involved in transducing defense response signals following apoplastic effector recognition. We then investigated whether DsEcp20-3 and DsEcp20-4 triggered cell death in the host species Pinus radiata by directly infiltrating purified protein into pine needles. Strikingly, as in the non-host species, DsEcp20-3 triggered cell death, while DsEcp20-4 did not. Collectively, our study describes two new candidate effector families with cell death-eliciting activity from D. septosporum and F. fulva and provides evidence that members of these families are recognized by plant immune receptors.
- ItemThe Potential Challenges and Limitations of Implementing Modern Office Design Features in Residential Spaces: A SPAR-4-SLR Approach(2024-09-03) Rotimi JOB; Moshood TD; Rotimi FE
- ItemBecoming and being language teacher educators: a collaborative reflexive account(Taylor and Francis Group, 2024-11-14) Nguyen M; Qi GYIn this study we employed reflexivity as a typology and a means to foster our own becoming and being as language teacher educators (LTEs). Specifically, drawing on reflexivity as mutual collaboration, we engaged in duoethnography where we were researcher-participants in each other’s narratives, with the capacity to be reflexive beings. We collaboratively inquired into our own and one another’s professional trajectories, demonstrating how our journeys of becoming and being LTEs were characterised by our social and linguistic identities, our work and interaction with language teachers, and the research and teaching praxis. Findings and discussion advocate a dialogue in the field, acknowledging the dispositions, challenges, and possibilities that reflexivity can offer for LTEs’ trajectories.
- ItemBatchHL+: batch dynamic labelling for distance queries on large-scale networks(Springer-Verlag GmbH Germany, part of Springer Nature, 2024-01) Farhan M; Koehler H; Wang QMany real-world applications operate on dynamic graphs to perform important tasks. In this article, we study batch-dynamic algorithms that are capable of updating distance labelling efficiently in order to reflect the effects of rapid changes on such graphs. To explore the full pruning potentials, we first characterize the minimal set of vertices being affected by batch updates. Then, we reveal patterns of interactions among different updates (edge insertions and edge deletions) and leverage them to design pruning rules for reducing update search space. These interesting findings lead us to developing a new batch-dynamic method, called BatchHL+ , which can dynamize labelling for distance queries much more efficiently than existing work. We provide formal proofs for the correctness and minimality of BatchHL+ which are non-trivial and require a delicate analysis of patterns of interactions. Empirically, we have evaluated the performance of BatchHL+ on 15 real-world networks. The results show that BatchHL+ significantly outperforms the state-of-the-art methods with up to 3 orders of magnitude faster in reflecting updates of rapidly changing graphs for distance queries.
- ItemGenomic data suggest parallel dental vestigialization within the xenarthran radiation(The Mersenne Center, 2023-01-01) Emerling CA; Gibb GC; Tilak M-K; Hughes JJ; Kuch M; Duggan AT; Poinar HN; Nachman MW; Delsuc FThe recent influx of genomic data has provided greater insights into the molecular basis for regressive evolution, or vestigialization, through gene loss and pseudogenization. As such, the analysis of gene degradation patterns has the potential to provide insights into the evolutionary history of regressed anatomical traits. We specifically applied these principles to the xenarthran radiation (anteaters, sloths, armadillos), which is characterized by taxa with a gradation in regressed dental phenotypes. Whether the pattern among extant xenarthrans is due to an ancient and gradual decay of dental morphology or occurred repeatedly in parallel is unknown. We tested these competing hypotheses by examining 11 core dental genes in most living species of Xenarthra, characterizing shared inactivating mutations and patterns of relaxed selection during their radiation. Here we report evidence of independent and distinct events of dental gene loss in the major xenarthran subclades. First, we found strong evidence of complete enamel loss in the common ancestor of sloths and anteaters, suggested by the inactivation of five enamel-associated genes (AMELX, AMTN, MMP20, ENAM, ACP4). Next, whereas dental regression appears to have halted in sloths, presumably a critical event that ultimately permitted adaptation to an herbivorous lifestyle, anteaters continued losing genes on the path towards complete tooth loss. Echoes of this event are recorded in the genomes of all living anteaters, being marked by a 2-bp deletion in a gene critical for dentinogenesis (DSPP) and a putative shared 1-bp insertion in a gene linked to tooth retention (ODAPH). By contrast, in the two major armadillo clades, genes pertaining to the dento-gingival junction and amelogenesis appear to have been independently inactivated prior to losing all or some enamel. These genomic data provide evidence for multiple pathways and rates of anatomical regression, and underscore the utility of using pseudogenes to reconstruct evolutionary history when fossils are sparse
- ItemFour microlensing giant planets detected through signals produced by minor-image perturbations(EDP Sciences on behalf of The European Southern Observatory, 2024-07) Han C; Bond IA; Lee C-U; Gould A; Albrow MD; Chung S-J; Hwang K-H; Jung YK; Ryu Y-H; Shvartzvald Y; Shin I-G; Yee JC; Yang H; Zang W; Cha S-M; Kim D; Kim D-J; Kim S-L; Lee D-J; Lee Y; Park B-G; Pogge RW; Abe F; Bando K; Barry R; Bennett DP; Bhattacharya A; Fujii H; Fukui A; Hamada R; Hamada S; Hamasaki N; Hirao Y; Silva SI; Itow Y; Kirikawa R; Koshimoto N; Matsubara Y; Miyazaki S; Muraki Y; Nagai T; Nunota K; Olmschenk G; Ranc C; Rattenbury NJ; Satoh Y; Sumi T; Suzuki D; Tomoyoshi M; Tristram PJ; Vandorou A; Yama H; Yamashita K; Bachelet E; Rota P; Bozza V; Zielinski P; Street RA; Tsapras Y; Hundertmark M; Wambsganss J; Wyrzykowski Ł; Jaimes RF; Cassan A; Dominik M; Rybicki KA; Rabus MAims. We investigated the nature of the anomalies appearing in four microlensing events KMT-2020-BLG-0757, KMT-2022-BLG-0732, KMT-2022-BLG-1787, and KMT-2022-BLG-1852. The light curves of these events commonly exhibit initial bumps followed by subsequent troughs that extend across a substantial portion of the light curves. Methods. We performed thorough modeling of the anomalies to elucidate their characteristics. Despite their prolonged durations, which differ from the usual brief anomalies observed in typical planetary events, our analysis revealed that each anomaly in these events originated from a planetary companion located within the Einstein ring of the primary star. It was found that the initial bump arouse when the source star crossed one of the planetary caustics, while the subsequent trough feature occurred as the source traversed the region of minor image perturbations lying between the pair of planetary caustics. Results. The estimated masses of the host and planet, their mass ratios, and the distance to the discovered planetary systems are (Mhost/M☉, Mplanet/MJ, q/10−3, DL/kpc) = (0.58−+00.3033, 10.71−+56.6117, 17.61 ± 2.25, 6.67+−01.9330) for KMT-2020-BLG-0757, (0.53+−00.3131, 1.12+−00.6565, 2.01 ± 0.07, 6.66+−11.1984) for KMT-2022-BLG-0732, (0.42−+00.2332, 6.64−+43.9864, 15.07 ± 0.86, 7.55+−01.8930) for KMT-2022-BLG-1787, and (0.32+−00.3419, 4.98+−52.4294, 8.74 ± 0.49, 6.27+−01.9015) for KMT-2022-BLG-1852. These parameters indicate that all the planets are giants with masses exceeding the mass of Jupiter in our solar system and the hosts are low-mass stars with masses substantially less massive than the Sun.
- ItemDifferent nightmares, shared dreams? Australia and New Zealand's intuitive alliance(Taylor and Francis Group, 2024-10-23) Powles A; Wallis JWhat does this apparent relegation of the strategic significance of Australia’s relationship with New Zealand to a partnership in Australia’s 2023 Defence Strategic Review tell us about the status of the Australia-New Zealand alliance? Based on interviews and roundtables with leaders, officials, and academics in both countries in late 2023 and early 2024, we argue that the depth and breadth of Australia and New Zealand’s defence, economic, regulatory, and people-to-people cooperation and integration has made their relationship ‘intuitive’. That is, Australia and New Zealand’s relationship has come to be seen as part of the natural order of things, so that the two countries see each other as a natural, permanent partner, parting company with whom is unthinkable. But we also argue that this may prevent the two neighbours from recognising and responding to tensions. To address this, we examine differences between the two countries’ perceptions of themselves, their strategic interests, and their alliance, and find that the management of expectations will continue to generate tensions. While we conclude that these tensions will not fundamentally undermine the relationship, we acknowledge that it has not yet been seriously tested, for example by conflict in East Asia.
- ItemGymnema lactiferum: A Review of Its Traditional Applications, Phytochemical Constituents, and Biological Properties(Wiley Periodicals LLC, 2024-10-16) Weerasinghe DMKP; Brough L; Everett DW; Rashidinejad AHumanity has a longstanding reliance on natural plants for medicinal purposes, and Gymnema lactiferum (G. lactiferum) has emerged as a medicinal plant with deep-rooted traditional usage. Throughout history, this plant has been an integral part of traditional medical systems, demonstrating diverse therapeutic effects. Notably, among these effects is its ability to decrease blood glucose concentration in diabetic patients, impart cooling effects, serve as an anabolic and rehydrating agent, stimulate spermiogenesis, and exhibit wormicidal properties. Furthermore, G. lactiferum has been used in treating conditions such as hemorrhoids cancers, anorexia, and as a cardiac stimulant. The primary objective of this review is to comprehensively gather and critically assess research findings regarding the medicinal properties of G. lactiferum, specifically emphasizing the bioactive compounds responsible for these properties. Previous studies have documented the presence of various phytochemicals in G. lactiferum, which are associated with some biological activities, including antioxidative, anti-hyperglycemic, cholesterol-regulating, and anti-inflammatory properties. Additionally, this review explores potential future applications for this plant. Beyond its medicinal significance, extracts derived from G. lactiferum demonstrate promise for future nutritional applications. This review highlights the potential use of G. lactiferum as an herbal medicine by critically assessing research on its medicinal value.
- ItemVisible Light Positioning-Based Robot Localization and Navigation(MDPI (Basel, Switzerland), 2024-01-01) Chew M-T; Alam F; Noble FK; Legg M; Gupta GS; Pak JMVisible light positioning or VLP has been identified as a promising technique for accurate indoor localization utilizing pre-existing lighting infrastructure. Robot navigation is one of the many potential applications of VLP. Recent literature shows a small number of works on robots being controlled by fusing location information acquired via VLP that uses a rolling shutter effect camera as a receiver with other sensor data. This paper, in contrast, reports on the experimental performance of a cartesian robot that was controlled solely by a VLP system using a cheap photodiode-based receiver rigidly attached to the robot’s end-effector. The receiver’s position was computed using an inverse-Lambertian function for ranging followed by multi-lateration. We developed two novel methods to leverage the VLP as an online navigation system to control the robot. The position acquired from the VLP was used by the algorithms to determine the direction the robot needed to move. The developed algorithms guided the end-effector to move from a starting point to target/destination point(s) in a discrete manner, determined by a pre-determined step size. Our experiments consisted of the robot autonomously repeating straight line-, square- and butterfly-shaped paths multiple times. The results show median errors of 27.16 mm and 26.05 mm and 90 percentile errors of 37.04 mm and 47.48 mm, respectively, for the two methods.
- ItemMeta-analysis quantifying the potential of dietary additives and rumen modifiers for methane mitigation in ruminant production systems(Elsevier B.V. on behalf of KeAi Communications Co. Ltd, 2021-12) Almeida AK; Hegarty RS; Cowie AIncreasingly countries are seeking to reduce emission of greenhouse gases from the agricultural industries, and livestock production in particular, as part of their climate change management. While many reviews update progress in mitigation research, a quantitative assessment of the efficacy and performance-consequences of nutritional strategies to mitigate enteric methane (CH4) emissions from ruminants has been lacking. A meta-analysis was conducted based on 108 refereed papers from recent animal studies (2000-2020) to report effects on CH4 production, CH4 yield and CH4 emission intensity from 8 dietary interventions. The interventions (oils, microalgae, nitrate, ionophores, protozoal control, phytochemicals, essential oils and 3-nitrooxypropanol). Of these, macroalgae and 3-nitrooxypropanol showed greatest efficacy in reducing CH4 yield (g CH4/kg of dry matter intake) at the doses trialled. The confidence intervals derived for the mitigation efficacies could be applied to estimate the potential to reduce national livestock emissions through the implementation of these dietary interventions.
