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Background: High-intensity interval training (HIIT) remains a promising exercise mode in managing cardiometabolic health. Large-scale analyses are necessary to understand its magnitude of effect on important cardiometabolic risk factors and inform guideline recommendations. Objective: We aimed to perform a novel large-scale meta-analysis on the effects of HIIT on cardiometabolic health in the general population. Methods: PubMed (MEDLINE), the Cochrane library and Web of Science were systematically searched. Randomised controlled trials (RCTs) published between 1990 and March 2023 were eligible. Research trials reporting the effects of a HIIT intervention on at least one cardiometabolic health parameter with a non-intervention control group were considered. Results: This meta-analysis included 97 RCTs with a pooled sample size of 3399 participants. HIIT produced significant improvements in 14 clinically relevant cardiometabolic health parameters, including peak aerobic capacity (VO2) [weighted mean difference (WMD): 3.895 ml min−1 kg−1, P < 0.001), left ventricular ejection fraction (WMD: 3.505%, P < 0.001), systolic (WMD: − 3.203 mmHg, P < 0.001) and diastolic (WMD: − 2.409 mmHg, P < 0.001) blood pressure, resting heart rate (WMD: − 3.902 bpm, P < 0.001) and stroke volume (WMD: 9.516 mL, P < 0.001). Body composition also significantly improved through reductions in body mass index (WMD: − 0.565 kg m−2, P < 0.001), waist circumference (WMD: − 2.843 cm, P < 0.001) and percentage body fat (WMD: − 0.972%, P < 0.001). Furthermore, there were significant reductions in fasting insulin (WMD: − 13.684 pmol L−1, P = 0.004), high-sensitivity C-reactive protein (WMD: − 0.445 mg dL−1, P = 0.043), triglycerides (WMD: − 0.090 mmol L−1, P = 0.011) and low-density lipoprotein (WMD: − 0.063 mmol L−1, P = 0.050), concurrent to a significant increase in high-density lipoprotein (WMD: 0.036 mmol L−1, P = 0.046). Conclusion: These results provide further support for HIIT in the clinical management of important cardiometabolic health risk factors, which may have implications for physical activity guideline recommendations. [ABSTRACT FROM AUTHOR]

Summary: Cyperus sect. Incurvi (Cyperaceae) contains 31 species worldwide, with important continental radiations in Australasia, Tropical Africa and Madagascar, and the Neotropics. Here, a monograph of the African and Madagascan species of Cyperus sect. Incurvi is presented, including descriptions, illustrations, synonymy, notes on habitat and ecology, geographic distribution ranges and conservation assessments. Our results identify eight species of Cyperus sect. Incurvi endemic to Madagascar, and a further three species native to Tropical Africa. Seven species of Cyperus sect. Incurvi have been typified herein. Six rare Madagascan endemics are assessed as threatened with extinction. [ABSTRACT FROM AUTHOR]

Background: Many plants contain phytotoxic alkaloids to deter herbivorous pests and grazing animals. Alkaloids include quinolizidine and indole alkaloids found in the lupin (Lupinus spp.), an ornamental flower and emerging protein crop, as well as pyrrolizidine alkaloids in the ragwort (Senecio jacobaea), an invasive, weed-like flower. When lupins and ragworts are present in large densities in fields, there is a concern that alkaloids may leach into freshwater environments in amounts that may affect non-target organisms, such as Daphnia magna. This study aimed to investigate (i) the acute toxicity of alkaloids (gramine, heliotrine, lupanine, lupinine, monocrotaline, monocrotaline N-oxide, senecionine and sparteine) in D. magna, (ii) the contribution of these individual alkaloids to lupin plant extract toxicity, (iii) the longer term reproductive effects of a representative alkaloid, sparteine, and conclude with (iv) a tentative risk assessment for the sum of alkaloids measured in soil and surface waters. Results: The alkaloids exhibited toxicity, with 48 h EC50 values in the range of 5.6 to > 100 mg/L. The 48 h EC50 of the Lupinus angustifolius plant extract was 1.38 mg/L, which was far more toxic than the simulated extract where lethality was < 10% at 10 mg/L after 48 h. Hence, non-measured compounds may have contributed to the joint toxicity. Daphnid mothers exposed to > 2.5 mg/L sparteine produced significantly fewer and smaller offspring during the 21-day exposure, making chronic effects occur at concentrations approximately 10-fold lower than the 48 h EC50 for sparteine. The risk assessment of cumulated alkaloids measured in drain, running and pond waters showed a potential risk, particularly for stagnant pond water, where concentrations were severalfold higher than in the drain and running waters. Conclusions: The results highlight that natural toxins may contribute to poor chemical quality of natural waters, and that natural toxins from upcoming crops or invasive weeds should be considered in aquatic risk assessments. [ABSTRACT FROM AUTHOR]

Many plants persist by resprouting after disturbance. However, the benefits of resprouting (survival) may be traded off against height growth and reproduction. Resources (total non-structural carbohydrates-TNC) that could be allocated to growth or reproduction are stored or mobilised to support resprouting. TNC may either be stored by accumulation where availability exceeds the requirements for growth, or by reserve formation when storage is at the expense of growth. Thus, the mechanism of storage and resource allocation may differ between good (R+) and poor (R−) resprouters in response to nutrient availability and disturbance regime. R+ species typically reserve resources to ensure a rapid resprouting response to disturbance. We test whether R+ and R− species in coastal forest, under chronic wind disturbance, differ in growth rates, biomass allocation, leaf traits, water relations and storage of TNC. Seedlings from three confamilial pairs of R+ and R− tree species were subjected to nitrogen addition, water stress and clipping (simulating herbivory) treatments under greenhouse conditions. R− species had greater height growth rates, larger specific leaf area, lower root mass ratio and lower root TNC than R+ species. These differences between R+ and R− species were maintained irrespective of the levels of nitrogen, water and clipping treatments. R+ species did not increase their TNC concentration under nutrient and water stress, indicating that TNC is stored by reserve formation. R+ species appeared to trade-off growth against storage, while R− species did not. In R+ species, reserve formation is likely a bet-hedging strategy against occasional strong selection events in addition to chronic wind stress. By trading off height growth for better resprouting ability, good resprouters may be able to persist at more frequently disturbed sites (e.g., dune crests and windward slopes), while poor resprouters that have faster height growth can dominate less disturbed sites. [ABSTRACT FROM AUTHOR]

Dispersal or recruitment limitation may arrest succession after disturbance. In north-eastern South Africa the Acacia karroo successional pathway is used to facilitate coastal forest recovery after strip-mining. However, although A. karroo establishes naturally, it forms monospecific stands, arresting forest succession for decades. This casts doubt on the efficacy of this restoration pathway. We investigated the causes of arrested succession. The seed and seedling banks of A. karroo stands and of forest at Cape Vidal, and three A. karroo stands (7-27 years old) on rehabilitated strip-mined dunes at nearby Richards Bay were examined. The establishment and growth of seedlings at Cape Vidal were also considered. The seed bank was larger and more diverse in forest, but the seedling bank was larger in Acacia stands. At Richards Bay, the size of the seed bank increased and the seedling bank decreased with Acacia stand age. Excluding mammalian herbivores in Acacia stands at Cape Vidal resulted in greater species richness and survival of naturally established seedlings, as well as two experimentally planted species. Neither seed dispersal nor seedling establishment limited recruitment of tree species in Acacia stands. Herbivory arrested forest succession by causing the differential mortality of seedlings. In contrast, at Richards Bay where there were few mammalian herbivores, the advanced regeneration in A. karroo stands converged on the diversity of nearby forests 29 years after restoration. Controlling herbivore access and seeding Acacia stands with forest species are site-specific options for preventing arrested succession when using the A. karroo successional pathway. [ABSTRACT FROM AUTHOR]

The regeneration niche is commonly partitioned along a gradient from shade-tolerant to shade-intolerant species to explain plant community assembly in forests. We examined the shade tolerance of tree seedlings in a subtropical coastal forest to determine whether the ecological filtering effect of a dominant, synchronously monocarpic herb ( Isoglossa woodii) selects for species at either end of the light response continuum during the herb's vegetative and reproductive phases. Photosynthetic characteristics of seedlings of 20 common tree species and the herb were measured. Seedlings were grown in the greenhouse at 12-14% irradiance, and their light compensation points measured using an open-flow gas exchange system. The light compensation points for the tree species were low, falling within a narrow range from 2.1 ± 0.8 μmol m s in Celtis africana to 6.4 ± 0.7 μmol m s in Allophylus natalensis, indicating general shade tolerance, consistent with a high and narrow range of apparent quantum yield among species (0.078 ± 0.002 mol CO mol photon). Rates of dark respiration were significantly lower in a generalist pioneer species ( Acacia karroo) than in a forest pioneer ( C. africana), or in late successional phase forest species. We argue that the general shade tolerance, and phenotypic clustering of shade tolerance, in many tree species from several families in this system, is a result of ecological filtering by the prevailing low light levels beneath the I. woodii understorey, which excludes most light-demanding species from the seedling community. [ABSTRACT FROM AUTHOR]

We studied avian dispersal of seeds from the hemiparasitic mistletoe Plicosepalus acaciae (Loranthaceae) to its tree hosts Acacia raddiana and A. tortilis in the Syrian–African Rift (Arava) valley, Israel. The Yellow-vented Bulbul ( Pycnonotus xanthopygos) was the sole avian visitor observed feeding on mistletoe fruits. Bulbuls consumed mistletoe fruits whenever they were available, but the fruits only constituted a significant portion of the diet (71% of foraging attempts) when they were most abundant. These birds are potentially good dispersal vectors of P. acaciae because they swallowed the fruit whole and defecated viable seeds that were covered in a viscid pulp, which allowed the seeds to adhere to substrates when voided. In addition, bulbuls spent a large proportion (66–93%) of total observation time perched in Acacia trees, allowing for directed dispersal. Ephemeral river valleys (wadis) with high mistletoe infection were adjacent to those containing no infections, demonstrating that mistletoe dispersal is common within, but not among wadis. This is consistent with the flight behaviour in bulbuls, which do not typically move among wadis. We combined data on bulbul movements between Acacia trees with transit times of mistletoe seeds to create a hypothetical seed shadow as a function of distance from the parent mistletoe plant. Because they are directed dispersers, the movement patterns of bulbuls may explain the current distribution of P. acaciae in the Arava valley. [ABSTRACT FROM AUTHOR]

Dominant understorey species influence forest dynamics by preventing tree regeneration at the seedling stage. We examined factors driving the spatial distribution of the monocarpic species Isoglossa woodii, a dominant understorey herb in coastal dune forests, and the effect that its cover has on forest regeneration. We used line transects to quantify the area of the forest understorey with I. woodii cover and with gaps in the cover. Paired experimental plots were established in semi-permanent understorey gaps with I. woodii naturally absent and in adjacent areas with I. woodii present to compare plant community composition, soil, and light availability between the two habitats. Isoglossa woodii was widespread, covering 65–95% of the understorey, while gaps covered the remaining 5–35% of the area. The spatial distribution of this species was strongly related to tree canopy structure, with I.␣woodii excluded from sites with dense tree cover. Seedling establishment was inhibited by low light availability (<1% of PAR) beneath I.␣woodii. When present, I. woodii reduced the density and species richness of tree seedlings. The tree seedling community beneath I. woodii represented a subset of the seedling community in gaps. Some species that were found in gaps did not occur beneath I. woodii at all. There were no significant differences between the sapling and canopy tree communities in areas with I. woodii gaps and cover. In the coastal dune forest system, seedling survival under I. woodii is dependent on a species’ shade tolerance, its ability to grow quickly during I. woodii dieback, and/or the capacity to regenerate by re-sprouting and multi-stemming. We propose a general conceptual model of forest regeneration dynamics in which the abundant understorey species, I. woodii, limits local tree seedling establishment and survival but gaps in the understorey maintain tree species diversity on a landscape scale. [ABSTRACT FROM AUTHOR]

North American coastal sandplain heathlands are unique in species composition and vegetation, but the extent to which edaphic factors influence the structure of these communities is currently debated. It was hypothesized that salt spray and edaphic factors maintain the dwarf stature and community composition of heathlands by limiting plant growth and excluding competitively dominant woody species close to the ocean. Field surveys were carried out to investigate the spatial patterns of salt spray accumulation, soil salt and soil moisture. High salt spray correlated significantly with increased leaf necrosis and water stress in Myrica pensylvanica and with decreased plant height. Plant community composition changed across a salt spray and soil gradient, as well. Distinctive sub-communities were identified that separated according to soil salt and soil moisture but salt spray was the main factor affecting sites occupied only by heathland vegetation. Results from this study suggest that salt spray suppresses the growth of heathland plants in close proximity to the ocean, and therefore maintains the low stature in these dwarf shrublands. This research also demonstrates that the physical environment influences the community structure in heathlands, particularly by limiting tree species from growing in high salt spray, low water availability sites. [ABSTRACT FROM AUTHOR]

Rabies is a viral zoonosis transmitted by vampire bats across Latin America. Substantial public health and agricultural burdens remain, despite decades of bats culls and livestock vaccinations. Virally vectored vaccines that spread autonomously through bat populations are a theoretically appealing solution to managing rabies in its reservoir host. We investigate the biological and epidemiological suitability of a vampire bat betaherpesvirus (DrBHV) to act as a vaccine vector. In 25 sites across Peru with serological and/or molecular evidence of rabies circulation, DrBHV infects 80–100% of bats, suggesting potential for high population-level vaccine coverage. Phylogenetic analysis reveals host specificity within neotropical bats, limiting risks to non-target species. Finally, deep sequencing illustrates DrBHV super-infections in individual bats, implying that DrBHV-vectored vaccines might invade despite the highly prevalent wild-type virus. These results indicate DrBHV as a promising candidate vector for a transmissible rabies vaccine, and provide a framework to discover and evaluate candidate viral vectors for vaccines against bat-borne zoonoses. Here, Griffiths et al. show infection of 80–100% of sampled vampire bats in Peru with a newly discovered betaherpesvirus (DrBHV) that exhibits specificity within neotropical bats and evidence for superinfection. These data suggest that DrBHV could be a candidate for virally vectored vaccines that spread autonomously through a bat population. [ABSTRACT FROM AUTHOR]