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Exposure to unpleasant environmental conditions can lead to the degradation of polymer material. This study presents an experimental investigation of the long-term hydrothermal and physical ageing behaviour of bio-based photopolymer resin. Bio-based resin specimens were prepared using vat photopolymerization-based 3D printing and submersed in water at 28.5 °C (SW-28.5 °C), 50 °C (SW-50 °C) and 75 °C (SW-75 °C) for 90 days to evaluate the influence of moisture, temperature and ageing time on the characteristics of bio-based resin specimens. Several tests were performed, including moisture absorption, fourier transform infrared spectroscopy (FTIR), tensile, hardness and microstructural tests to determine the mechanical, chemical and microstructural characteristics of bio-based resin specimens. The result showed that moisture absorption of SW-75 °C specimens were far higher up to 3 times extra moisture content than dry-fresh (DA) specimens. A direct relationship between moisture absorption and reduction in tensile and hardness properties was observed, with the tensile strength and hardness of specimens decreased up to 55.6% and 7.8%, respectively, after submersion in water at 28.5 °C for 90 days. As expected, the bio-based resin specimens showed notable physical degradation after being submersed in water at 75 °C, indicated by a decrease in tensile strength up to 58.9% only after one day of submersion. Formation of cracks on the specimens was observed after submersion in water at 50 °C and 75 °C, which also contributes to a decrease in the mechanical properties of bio-based resin specimens. The FTIR analysis showed several absorption peaks were getting less visible after submersion in water at 75 °C, indicating the notable degradation of bio-based resin specimens. Accordingly, understanding the polymer degradation is very important in the context of design considerations and predicting the service life of polymeric components.

The natural distribution of Cycas micronesica includes three island groups. Damage to the widespread tree from the armored scale Aulacaspis yasumatsui was initiated with the 2003 invasion of Guam and the 2007 invasion of Rota. This herbivore has threatened the unique gymnosperm species with extinction. The number and identity of co-occurring consumers are dissimilar among disjunct insular subpopulations, and six of these habitats were used to assess tree mortality trends to confirm that A. yasumatsui stands alone as the greatest threat to species persistence. Following the initial infestation outbreak of this pest into each new subpopulation, the standing seedlings and saplings were the first to be culled, the juvenile plants were the next to be culled, and then the adult trees were killed more slowly thereafter. The timing of this plant population behavior did not differ among habitats with five other consumers, three other consumers, one other consumer, or no other consumers. We have shown that A. yasumatsui acting as the sole biotic threat in an isolated subpopulation can generate a decline in survival that is as rapid as when it is acting in conjunction with up to five other consequential consumers. This armored scale is the most acute threat to C. micronesica, and adding other specialist herbivores to the scale herbivory does not alter the speed and extent of initial plant mortality.

Knowledge about the position of tree roots is needed to understand tree biology and inform management decisions. Cycad species produce pachycaul stems and are not represented in the published studies on the relationships between aboveground tree traits and root system spread. We measured the radius of root egress from 6-year-old Cycas edentata de Laub., Cycas micronesica K.D. Hill, and Cycas nitida K.D. Hill & A. Lindstrom plants in an ex situ cycad germplasm collection into an 8-m-wide buffer zone in which no trees were growing. We then determined the relationships of root system radius to aboveground plant traits. The root system radius extended 5.2 to 7.5 m from the base of the stems, and was 3.5 times the plant height, 32 to 36 times the stem diameter, and 3.6 to 4.2 times the radius of the canopy dripline. Values for root radius in relation to plant height and canopy radius exceeded published data for leptocaul tree species, but values for stem diameter were less than these data. These findings on the location of cycad roots provide adaptive management cycad knowledge to inform horticulture decisions such as avoidance of roots during soil disturbance and placement of fertilizers and systemic pesticides.

Trees contribute to ecosystem nutrient cycling through the amount, timing, and composition of litterfall. Understanding the nature of this contribution from endangered tree species may aid in species and habitat recovery efforts. Serianthes nelsonii is an endangered tree species from the Mariana Islands, and little is known about litterfall dynamics. The timing of leaf, fruit, and stem litterfall was determined to more fully understand the return of nutrients via litter. The total annual litterfall was 272.8 g·m−2, with 45% represented by leaves, 48% represented by stems, and 7% represented by fruits. Stem litterfall weight contrasted more from month to month than the other organs, and leaf litterfall exhibited the most even distribution throughout the year. The timing of fruit and stem litterfall was influenced by the timing of extreme wind events. Leaf litter contributed nutrients in the following order: carbon > calcium > nitrogen > potassium > magnesium > iron > phosphorus > manganese > boron > zinc > copper. Fruit and stem litter contributed nutrients in the following order: carbon > calcium > nitrogen > magnesium > potassium > phosphorus > iron > manganese > boron > zinc > copper. Based on carbon/nitrogen, the stem litter exhibited the lowest quality and leaf litter exhibited the highest quality for speed of nutrient release via decomposition. Conservationists may use this knowledge to more fully integrate S. nelsonii trees into habitat management plans.

Structures, morphological control, and antibacterial activity of silver-titanium dioxide (Ag/TiO2) micro-nanocomposite materials against Staphylococcus aureus are investigated in this study. Horizontal vapor phase growth (HVPG) technique was used to synthesize the Ag/TiO2 micro-nanomaterials, with parameters of growth temperature and baking time. The materials were characterized by using scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, and atomic force microscope (AFM). The result indicated that the HVPG technique is able to synthesize Ag/TiO2 with many shapes in micro- and nanoscale such as nanoparticles, nanorods, triangular nanomaterials, and nanotubes. The results showed that the shape of micro- and nanocomposites material could be arranged by adjusting the parameters. The results revealed that the nanorods structure were obtained at 1000°C growth temperature and that 8 hours of baking time was ideal for antibacterial application. Treating the S. aureus stock with Ag/TiO2 nanocomposites is able to reduce bacterial growth with a significant result.

The literature covering the biology, ecology, horticulture, and conservation of the critically endangered tree Serianthes nelsonii Merr. was reviewed. The roots, stems, and leaves of this charismatic legume tree revealed highly plastic traits and responded positively to horticultural manipulations to improve the quality of container-grown transplants. Pre-sowing seed treatments of seed coat scarification and 1 h of imbibition generated 85% to 90% germination at a temperature optimum of 26 °C. Adventitious root formation on air layers and successful unions on approach grafts were 100%. Seedling and sapling growth was maximum under 25% to 50% sunlight transmission, limited irrigation to ensure adequate root zone aeration, repetitive stem tip pruning to increase root:shoot quotient, and thigmic stress to retain an orthotropic orientation of stems. In situ regeneration on Guam was substantial but recruitment from seedling to sapling was nil. High quality leaf litter chemistry enabled rapid decomposition, and soils beneath the tree exhibited unique chemical traits that increased ecosystem health by creating spatial heterogeneity. The greatest unanswered questions focus on plant mortality. Research is needed to determine the reasons for the mortality of in situ seedlings, mortality within transplantation projects on Guam, and the mortality of 60% of the mature in situ tree population during the 26-year implementation of the national recovery plan. Horticultural researchers are ideally positioned to answer these urgent questions.

The growth of synchronized leaf flushes or male cones on Cycas trees is an ephemeral event, and non-structural carbohydrates (NSCs) are likely deployed from stem and root storage tissues to support their construction. The relationships among various stem NSCs and these rapid growth events have not been studied to date. Monosaccharides, disaccharides, and starch were quantified in Cycas micronesica stem tissue prior to and immediately after the growth of leaf flushes or male cones to determine the influences on the concentration of these carbohydrates. The pre-existing leaves were removed from half of the plants to determine if the elimination of this carbon source would influence the NSC behaviors. Starch and sucrose dominated the NSC profiles, and these two NSCs declined following cone or new leaf growth. Removal of pre-existing leaves generated a greater decline in starch and sucrose for cone growth, and a greater decline in sucrose, but not starch following new leaf growth than in control trees with no leaf removal. The initial differences in starch and sucrose among cortex, vascular, and pith tissues disappeared as the concentrations declined in all three tissue categories to reach similar post-growth concentrations among the stem tissue categories. The fructose, glucose, and maltose behaviors were not consistent, and their concentrations were low such that their influence on the total NSC behaviors was minimal. These results provided indirect evidence that stem NSCs were mobilized to support ephemeral male cone and new leaf growth for this arborescent cycad. Growth of female strobili is slow and lengthy, so we did not include female trees in this study. The contributions of stem NSCs to female strobili growth remain to be studied with alternative methods.

An ex situ germplasm collection of the endangered Cycas micronesica was established in a transition zone between biodiverse native forest and mature stands of the invasive species Leucaena leucocephala. Soil chemical properties were determined for the 2 tree cover types to inform management decisions. Total carbon, total nitrogen, calcium, and net ammonification were greater in native forest cover than in L. leucocephala patches. Net nitrification and net mineralization were greater under L. leucocephala cover. Trace metals also differed between the 2 forest cover types, with chromium, cobalt, and nickel accumulating to greater concentration under L. leucocephala cover and zinc accumulating to greater concentration under native forest cover. The results indicated that L. leucocephala cover generated substantial changes in soil chemical properties when compared with native forest tree cover, illuminating one means by which understory vegetation may be affected by changes in invasive tree cover.

Background: The physical health of people with intellectual disabilities (ID) has been identified as an area of ongoing concern and priority. Research has increasingly focused on cancer, with studies indicating that people with ID are at an increased risk of cancer and of mortality, compared with the general population. This review aims to systematically identify and synthesise the published academic literature exploring cancer risk‐factor and symptom awareness among people with IDs, carers and healthcare professionals. Methods: In line with Arksey and O'Malley's (2005) framework for scoping reviews, five incremental stages were followed: (1) identifying research question, (2) identifying relevant studies, (3) study selection, (4) extracting and charting of data, and (5) collating, summarising and reporting results. Findings were reported according to the Preferred Reporting Items for Systematic Reviews and Meta‐analyses extension for scoping reviews (PRISMA‐Scr). Results: The search strategy identified 352 records, 16 records met all eligibility criteria and were included for review. The studies address a range of areas including knowledge and awareness of cancer risk‐factors and symptoms and interventions to promote awareness of cancer. Conclusions: Cancer risk‐factor and symptom awareness is low among adults with ID, paid and unpaid carers and healthcare practitioners (HCPs). Theoretically underpinned, co‐designed tools and interventions to improve awareness are lacking. There is uncertainty surrounding how to best support people with ID in raising cancer awareness, even within the professional healthcare environment. There is a predominance of research on breast cancer awareness. Future studies focusing on other cancers are needed to build a complete picture of awareness among adults with IDs, paid and unpaid carers, and HCPs. [ABSTRACT FROM AUTHOR]

The natural distribution of Cycas micronesica includes three island groups. Damage to the widespread tree from the armored scale Aulacaspis yasumatsui was initiated with the 2003 invasion of Guam and the 2007 invasion of Rota. This herbivore has threatened the unique gymnosperm species with extinction. The number and identity of co-occurring consumers are dissimilar among disjunct insular subpopulations, and six of these habitats were used to assess tree mortality trends to confirm that A. yasumatsui stands alone as the greatest threat to species persistence. Following the initial infestation outbreak of this pest into each new subpopulation, the standing seedlings and saplings were the first to be culled, the juvenile plants were the next to be culled, and then the adult trees were killed more slowly thereafter. The timing of this plant population behavior did not differ among habitats with five other consumers, three other consumers, one other consumer, or no other consumers. We have shown that A. yasumatsui acting as the sole biotic threat in an isolated subpopulation can generate a decline in survival that is as rapid as when it is acting in conjunction with up to five other consequential consumers. This armored scale is the most acute threat to C. micronesica, and adding other specialist herbivores to the scale herbivory does not alter the speed and extent of initial plant mortality. [ABSTRACT FROM AUTHOR]