Induction of compression wood inhibits development of spiral grain in radiata pine

Spiral grain refers to the helical patterns formed by the wood grain in the trunks of many tree species. In most gymnosperms, grain near the pith is vertical but wood formed after several years of growth has a slight to pronounced left-handed twist. Grain changes presumably involve the slow rotation of cells within the vascular cambium, but the mechanisms that allow this reorientation to occur remain unclear. Understanding this process is, however, important as the presence of strong spiral grain within the corewood of gymnosperms is a major wood quality issue devaluing cut timber. In this study, we measured wood grain in stems of Pinus radiata (radiata pine) saplings through reconstructions of resin canals that follow the grain, visualised by serial sectioning and scanning with circularly polarised light, and through X-ray computed microtomography (μCT) and image analysis in ImageJ. Vertical trees retained a symmetrical grain pattern that was weakly right-handed near the pith, but which became progressively more left-handed during the first eight months of growth. In tilted trees, however, the development of left-handed grain was inhibited by the formation of compression wood on the lower side of the tree whereas the wood on the upper side of the tree developed increasingly more left-handed grain as in the vertical controls. These results demonstrate that a previously unidentified link exists between compression wood formation and the inhibition of grain development

Treatment of wastewater from biomass pyrolysis and recovery of its organic compounds with char-assisted drying

This study proposes a new process that treats pyrolytic wastewater (PWW) from biomass pyrolysis with char-assisted drying. It can be operated at two modes: (I) one-stage drying for PWW treatment; and (II) two-stage drying and condensation for both treating PWW and recovering valuable chemicals (e.g., acetic acid). The process is proved via drying the mixture of a char and a synthetic PWW solution containing acetic acid, acetol, furfural, and phenol at different temperatures (60, 80, and 105 °C) and char-to-PWW mass ratios (1.0, 1.5, and 2.0). The results, supported by density functional theory (DFT) calculations, demonstrate that under Mode I, the char captures over 97.1% of the organic compounds in the PWW at 60 °C and a char-to-PWW ratio of 2.0, while evaporating almost all the water. The evaporated stream can be potentially discharged into the atmosphere without condensation or condensed into wastewater with a significantly reduced content of total organic carbon. Under Mode II, the char-PWW mixture is sequentially dried at 60 and 105 °C, with the exhaust gases being separately condensed. This yields a stream of purified acetic acid solution (concentration: ∼76 wt%) concentrated by a factor of ∼6.3 (compared with the PWW), with a recovery rate of ∼29%

Population genomics of a predatory mammal reveals patterns of decline and impacts of exposure to toxic toads

Mammal declines across northern Australia are one of the major biodiversity loss events occurring globally. There has been no regional assessment of the implications of these species declines for genomic diversity. To address this, we conducted a species-wide assessment of genomic diversity in the northern quoll (Dasyurus hallucatus), an Endangered marsupial carnivore. We used next generation sequencing methods to genotype 10,191 single nucleotide polymorphisms (SNPs) in 352 individuals from across a 3220-km length of the continent, investigating patterns of population genomic structure and diversity, and identifying loci showing signals of putative selection. We found strong heterogeneity in the distribution of genomic diversity across the continent, characterized by (i) biogeographical barriers driving hierarchical population structure through long-term isolation, and (ii) severe reductions in diversity resulting from population declines, exacerbated by the spread of introduced toxic cane toads (Rhinella marina). These results warn of a large ongoing loss of genomic diversity and associated adaptive capacity as mammals decline across northern Australia. Encouragingly, populations of the northern quoll established on toad-free islands by translocations appear to have maintained most of the initial genomic diversity after 16 years. By mapping patterns of genomic diversity within and among populations, and investigating these patterns in the context of population declines, we can provide conservation managers with data critical to informed decision-making. This includes the identification of populations that are candidates for genetic management, the importance of remnant island and insurance/translocated populations for the conservation of genetic diversity, and the characterization of putative evolutionarily significant units

Perspectives on Maritime Archaeology in Southeast Asia

Maritime archaeology in Southeast Asia is a vibrant area of research that entails a hugely diverse dataset. Historical and anthropological records are combined with archaeological material in attempts to interpret the tangible and intangible heritage connected to the use of the aquatic environment. Seas, rivers, and lakes create fluid environments and provide space for socioeconomic activities. The role of maritime archaeologists is to interpret that connection and exchange by looking at the issue from a water perspective, taking into account the intricate entanglement between humans, objects, and the watery environment that make up maritime communities. From this perspective, maritime archaeology has also developed specific theoretical frameworks to interpret archaeological data. This chapter provides an overview of the discipline in Southeast Asia, of the current projects and trends, and explores different ways of inquiry that can be used to apprehend human-environment interactions in sea, rivers, and lakes

Reviving botany in the curriculum: The botanical journey of two Western Australian early childhood teachers

Environmental education across the early years has become increasingly important in Australia since the implementation of the Early Years Learning Framework and the Australian Curriculum. These documents promote a connection to nature for young children as well as environmental responsibility. In Western Australia, large areas of natural environments are bush spaces, accessible by young children, families and schools. There is no existing research investigating early childhood teacher’s knowledge of plants in these bush spaces and the utilisation of these spaces in teaching botany as part of their teaching practice. The discussion in this article examines part of a larger year-long multi-site case study of the changes in the botanical understanding of two early childhood teachers of children aged 5–8 years, in Western Australian schools both before and after the Mosaic Approach, botanical practices and Indigenous knowledges were incorporated into their teaching practice. This article focuses on the changes of botanical literacies of the early childhood teachers specifically. The findings suggest that using inquiry-based and place-based methods and including First Nations Peoples’ perspectives about plants whilst teaching in the bush can significantly increase the plant knowledge and understanding of teachers, as well their own scientific and botanical literacies

The 3366 chickpea genomes for research and breeding

Genome sequences provide an unprecedented resource to rapidly develop modern crops. A recent paper by Varshney et al. provides genome variation maps of 3366 chickpea accessions. Here, we highlight how this breakthrough research can fundamentally change breeding practices of chickpea and potentially other crops

How does multi-set high-load resistance exercise impact neuromuscular function in normoxia and hypoxia?

This study examined whether hypoxia during multi-set, high-load resistance exercise alters neuromuscular responses. Using a single-blinded (participants), randomised crossover design, eight resistance-trained males completed five sets of five repetitions of bench press at 80% of one repetition maximum in moderate normobaric hypoxia (inspiratory oxygen fraction = 0.145) and normoxia. Maximal isometric bench press trials were performed following the warm-up, after 10 min of altitude priming and 5 min post-session (outside, inside and outside the chamber, respectively). Force during pre-/post-session maximal voluntary isometric contractions and bar velocity during exercise sets were measured along with surface electromyographic (EMG) activity of the pectoralis major, anterior deltoid and lateral and medial triceps muscles. Two-way repeated measures ANOVA (condition×time) were used. A significant time effect (p = 0.048) was found for mean bar velocity, independent of condition (p = 0.423). During sets of the bench press exercise, surface EMG amplitude of all studied muscles remained unchanged (p > 0.187). During maximal isometric trials, there were no main effects of condition (p > 0.666) or time (p > 0.119), nor were there any significant condition×time interactions for peak or mean forces and surface EMG amplitudes (p > 0.297). Lower end-exercise blood oxygen saturation (90.9 ± 1.8 vs. 98.6 ± 0.6%; p < 0.001) and higher blood lactate concentration (5.8 ± 1.4 vs. 4.4 ± 1.6 mmol/L; p = 0.007) values occurred in hypoxia. Acute delivery of systemic normobaric hypoxia during multi-set, high-load resistance exercise increased metabolic stress. However, only subtle neuromuscular function adjustments occurred with and without hypoxic exposure either during maximal isometric bench press trials before versus after the session or during actual exercise sets

Ozone efficiency on two Coleopteran insect pests and its effect on quality and germination of barley

Ozone (O3) is a potential fumigant to control pests in stored grain since it can safely and rapidly auto-decompose without leaving residues. In this study, the efficacy of O3 on all life stages of Rhyzopertha dominica (Fabricius) and Tribolium castaneum (Herbst) in barley and the physiological effects on barley and its quality were investigated. Complete control of all life stages of pests was obtained at 700 ppm for 1440 min of ozone exposure without negatively impacting the contents of soluble protein, moisture content, seed colour, hardness, and the weight of thousand barley seeds. The eggs and pupae of these two insects were the more tolerant stages than their larvae and adults. Prolonged exposure times (40 to 1440 min) and mortality assessment intervals (1, 2, and 7 days) increased O3 efficacy due to the reaction characteristics and delayed toxicity. Aging barley seeds appeared to be more sensitive to prolonged ozone duration than new seeds. A total of 20 and 40 min could promote germination rate, and longer O3 exposure (1440 min) was unfavourable for germination and seedling growth. Thus, it is imperative to select an optimal O3 exposure time to transfer ozone into quality contributors of final products and achieve the desired functional outcomes

Synthesis and characterization of novel silane derivatives of phenothiazinium photosensitisers

Phenothiazine based dyes are widely explored dyes for their antibacterial and photosensitising applications. Despite their amazing optical and photosensitising (theranostic) properties, their usage in nanomedicine is very low compared to other organic dyes. This is due to the lack of reactive functional groups for encapsulating them into metal oxide nanoparticles. This work describes the synthesis of three different phenothiazinium alkoxysilane derivatives by oxidative amination of 10H-phenothiazine using amino alkoxysilanes. The new derivatives were characterized using NMR, FT-IR, DSC/TGA, and mass spectral studies. Optical and photosensitising properties (absorption spectrum, photostability, and singlet oxygen quantum yield) of the silane derivatives were investigated using UV–Visible spectroscopy. These compounds are suitable for conjugation with silica in the sol-gel synthesis of silica nanoparticles and silica surface coaters, which will reduce dye leakage and improve the dye efficacy in the treatment of cancer and light activated antimicrobial surfaces

The role of glucose in cognition, risk of dementia, and related biomarkers in individuals without type 2 diabetes mellitus or the metabolic syndrome: A systematic review of observational studies

Background Excessive blood glucose promotes neuropathological cognitive decline in individuals with type 2 diabetes mellitus and the metabolic syndrome, but no systematic synthesis of the evidence for the same association exists in individuals without these conditions. Objectives To systematically review studies exploring the role of glucose on cognition, dementia risk, and related biomarkers in adults without diabetes or metabolic syndrome. Data sources We searched databases from inception until July 2021 and manually searched the reference lists of included studies. Risk of bias was assessed using the Joanna Briggs Institute tool. Results We found 46 observational studies including approximately 98,216 participants. Substantial heterogeneity in study results precluded drawing definitive conclusion whether blood glucose levels are associated with cognition or dementia risk. Higher blood glucose, however, was associated with greater amyloid burden, brain atrophy, and reduced cortical thickness. Conclusions and implications High glucose concentrations in blood may exacerbate dementia-related neuropathology but whether this translates into pathological cognitive decline or elevate dementia risk later in life remains unclear