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Vitamin D composition of Australian game products
No full textThe vitamin D content of many Australian game products is unknown. These foods are potential sources of vitamin D for remote-dwelling Aboriginal and Torres Strait Islander people, of whom 39% are vitamin D deficient (serum 25-hydroxyvitamin D3 (25(OH)D3) concentrations < 50 nmol/L). Vitamin D3, 25(OH)D3, vitamin D2 and 25(OH)D2 were measured by liquid chromatography-triple quadrupole mass spectrometry (LC-QQQ) in raw meat (camel, crocodile, emu, kangaroo), emu eggs and emu oil. Vitamin D3 (range, 0.5–14.5 μg/100 g) was found in all products except camel and kangaroo. All samples except kangaroo contained 25(OH)D3; some camel samples contained relatively high concentrations (range, 0.4–5.2 μg/100 g). Vitamin D2 was found in emu products and some kangaroo samples. We detected trace amounts of 25(OH)D2 in some camel and kangaroo samples. This study provides valuable insight into foods with a paucity of data on vitamin D content, showing that some are potentially useful sources of vitamin D
Morpho-physiology and cannabinoid concentrations of hemp (Cannabis sativa L.) are affected by potassium fertilisers and microbes under tropical conditions
No full textIndustrial hemp (Cannabis sativa L.) is a crop with the potential for multiple products. However, there is a lack of information regarding the effects of some key nutrients and soil microbiology. Potassium (K) and microbes can affect plant physiology, growth, and secondary metabolite production. A glasshouse experiment in a fully controlled growth room was undertaken to assess K requirements and effects on physiology on a tropical/subtropical variety of industrial hemp, ECO-GH15, bred for Australian conditions by Ecofibre (Brisbane, QLD, Australia). Increasing rates of K of conventional fertiliser liquid applications were applied to hemp plants and compared to a slow-release form containing soil microbes (SRK) under short daylength (12.5 h), simulating a tropical environment. Application of 11, 43 and 129 ppm of conventional fast-release potassium K as potassium sulphate (K2SO4), or a slow (controlled) release form (131 ppm of K), were applied to plants and their growth parameters compared. A series of physiological and growth response data was collected, including photosynthesis response to increasing active radiation (PAR or PPFD) and carbon dioxide (CO2), and cannabinoid production. Plant growth responses, such as stalk diameter, height, and shoot dry weight, increased with SRK application, while no differences were observed between the three increasing conventional K rates. The lower conventional K rate (11 ppm) resulted in increased photosynthetic activity up to 600–700 PPFD. Physiological data showed that the increasing K rate produced less efficient plants in terms of PPFD and CO2 utilisation. Cannabinoid analysis showed an increase in cannabidiol (CBD) and cannabidivarin (CBDV) at the higher K rate, while the SRK increased the production of delta-9-tetrahydrocannabinol (THC) and similar cannabinoids. This study revealed that sustained nutrient application improved plant photosynthesis and gas exchange regulation resulting in increased plant growth and cannabinoid production under tropical conditions, and helped to better understand the role of K in plant stress and physiological efficiency
Impact of different mulching treatments on weed flora and productivity of maize (Zea mays L.) and sunflower (Helianthus annuus L.)
Get PDFThe concerns on weed control through herbicides are increasing due to their negative impacts on environment and human health. Therefore, alternative weed management methods are inevitable for sustainable crop production and lowering the negative consequences of herbicides. Mulching is an environment-friendly weed management approach capable of substituting herbicides to significant extent. Therefore, this study evaluated the role of different mulching treatments on suppressing weed flora in maize (Zea mays L.) and sunflower (Helianthus annuus L.) crops. Furthermore, the impact of different mulching treatments on the productivity of both crops was also investigated. Three mulch treatments, i.e., plastic mulch (PLM), sorghum mulch (SM) and paper mulch (PM) along with two controls, i.e., weed-free (WF) and weedy-check (WC) were included in the study. Different mulch treatments significantly altered weed flora in both crops. The PLM and PM resulted in the highest suppression (43–47%) of weed flora compared to WC treatment in both crops. The highest and the lowest weed diversity was recorded for WC and WF treatments, respectively. Different allometric traits, i.e., leaf area index, crop growth rate and root length of both crops were significantly improved by PLM as compared to the WC. Overall, maize crop recorded higher density of individual and total weeds compared to sunflower with WC treatment. The density of individual and total weeds was significantly lowered by PLM compared to WC treatment in both crops. Similarly, higher growth and yield-related traits of both crops were noted with PLM compared to the rest of the mulching treatments. Results of the current study warrant that PLM could suppress weed flora and improve the productivity of both crops. However, PLM alone could not provide 100% control over weed flora; therefore, it should be combined with other weed management approaches for successful weed control in both crops
Understanding nurse characteristics that influence assessment and intention to treat pain in postoperative patients: An integrative literature review
No full textObjectives
An understanding of nurse characteristics that influence pain management, which are potentially amenable to change, can help to refine and improve nurse education and practice, resulting in better patient outcomes. The purpose of this review was to identify nurse characteristics that influence their assessment of and intention to treat postoperative pain.
Design
Integrative literature review.
Data sources
A systematic search of electronic databases (CINAHL, Scopus, PsycINFO, Medline, and Embase), using these constructs “pain assessment”, “pain management”, “postoperative pain”, “nurses”, “cultural beliefs” and “nurses’ perceptions” was conducted for the period 2000 to October 2020.
Review/Analysis methods
Following a systematic screening process, the included articles were analyzed and synthesized to identify themes and subthemes.
Results
A total of 40 articles were included with three main themes identified: nurse knowledge; nurse sociocultural factors, personal beliefs and attitudes, and other characteristics; and believing or doubting the patient. There was evidence that targeted education interventions can improve nurse knowledge and nurses’ clinical practice in relation to pain management. What was less clear was which nurse attitudes and biases influenced their pain management practice or how these could be changed.
Conclusions
More studies are needed to investigate the influence of cultural characteristics on pain assessment and management. There is a need for further quantitative studies that explore the relationship between nurse characteristics and their pain management practice. Intervention studies using innovative educational approaches that change attitudes and biases, and improve practice are needed
COVID-19 and earnings management: A comparison between Chinese family and non-family enterprises
No full textPurpose
The main objective of this study is to examine the impact of the COVID-19 pandemic on earnings management practices in China using a sample of family and non-family enterprises. More specifically, this study aims to examine whether the COVID-19 pandemic causes variation in Chinese listed family and non-family enterprises' operations, as reflected in the level of real earnings management (REM).
Design/methodology/approach
This study uses three standardised REM indicators, namely, the abnormal level of cash flows from operations, the abnormal level of production costs and the abnormal level of discretionary expenses. Ordinary least squares (OLS) regressions are applied to compare the earnings management of Chinese family and non-family enterprises during the pre-pandemic period (2017–2019) and the pandemic period (2020).
Findings
The authors find that Chinese listed non-family enterprises tend to participate in more REM activities than family enterprises before the COVID-19 outbreak. However, the opposite is true during the pandemic. The authors also find that COVID-19 has increased the involvement of family and non-family enterprises in REM activities.
Originality/value
The results of previous studies based on REM using Chinese listed firms may not be applicable under the new social background of COVID-19. As the period after the COVID-19 outbreak is relatively recent, Chinese researchers have yet to study it comprehensively. The present study is amongst the first empirical attempts investigating the effect of a pandemic financial reporting by investigating whether and how the burst of the COVID-19 crisis affected financial reporting through the earnings management practices of listed Chinese family and non-family enterprises. Such information is crucial because it can provide analysis for all stakeholders to make better decisions
New structural insights into densely assembled reduced graphene oxide membranes
Get PDFDensely assembled graphene-based membranes have attracted substantial interest for their widespread applications, such as compact capacitive energy storage, ion/molecular separation, gas barrier films, and flexible electronics. However, the multiscale structure of densely packed graphene membranes remains ambiguously understood. This article combines X-ray and light scattering techniques as well as dynamic electrosorption analysis to uncover the stacking structure of the densely stacked reduced graphene oxide (rGO) membranes. The membranes are produced by reducing graphene oxide (GO) membranes with hydrazine, during which the colloidal interactions between GO sheets are modulated by the electrolyte solution. In contrast to the common notion that direct reduction of densely assembled GO sheets in parallel tends to result in significant “graphitization”, this article unexpectedly discovers that the resultant densely packed rGO membrane can still retain the interconnected network nanochannels and show good capacitive performances. This inspires the development of a hierarchical structural model to describe the densely packed rGO membranes. This article further shows that the nanochannel network can be fine-tuned at the sub-nanometer level by tailoring the salt concentration and the reduction temperature to render exceptional volumetric capacitance and good rate performance for rGO membranes even with increased packing density
Isolated diaphragm weakness and the diagnostic value of phrenic nerve stimulation
Get PDFAcute onset, atraumatic, bilateral diaphragm paralysis due to isolated bilateral phrenic neuropathy is uncommon. Respiratory physicians should be alert to this disorder because it is associated with considerable morbidity and diagnosis is often delayed. These case reports highlight important aspects of the presentation, investigations and management of this disorder
Experimental studies on the generation and evolution of mineral porosity during fluid-mediated mineral replacement reactions
Get PDFThe porosity in minerals contributes to enhanced permeability for fluid flow in natural systems and engineering processes. Porosity can be created by fluid-mediated mineral replacement reactions. Such reaction-induced porosity can evolve with time, yet the mechanisms and kinetics of porosity creation and evolution remain poorly understood. This thesis presents experimental investigations on the creation and evolution of mineral porosity in two model replacement reactions, i.e., the replacement of calcite by gypsum and anhydrite with a positive volume change and the replacement of pentlandite by violarite and millerite with a negative volume change. These replacement reactions were conducted under mildly acidic hydrothermal conditions for up to 18 months, and the mineralogy, microstructure and porosity of the reaction products were quantitatively analysed by powder X-ray diffraction, (ultra) small-angle neutron scattering, high resolution scanning electron microscopy, focused-ion beam scanning electron microscopy, and X-ray micro-tomography. The results showed that porosity creation and evolution are highly dependent on mineral systems and reaction conditions.
In the calcite-gypsum-anhydrite mineral system, the experiments at 25-60 °C produced intragranular nanopores in gypsum replacing calcite. Because of the positive volume change, gypsum overgrowth also occurred on the grain surface, and the gypsum in the overgrowth region contained intergranular micropores. Porosity coarsening was rapid (a few weeks) in the replacement region, leading to the formation of micro-voids in the core of gypsum grains. The replacement reaction was sensitive to temperature. When the experiments were conducted at a higher temperature of 220 °C, anhydrite was formed instead of gypsum. Porosity evolution in anhydrite was different when compared to gypsum at lower temperatures.
In the pentlandite-violarite-millerite mineral system, only replacement occurred, likely because the negative volume change does not require overgrowth for additional space. The replacement was sensitive to temperature and solution pH. The experiments conducted at 125 °C and pH 4 produced permeable nanopores leading to the complete replacement of pentlandite; these nanopores coarsened slowly during the 17 months of experiment and occurred preferentially near the grain surface. However, in experiments conducted at 125 °C and pH 5, violarite became impermeable in partially replaced grains due to hematite precipitation in the pore space, blocking the fluid flow. At a higher temperature of 220 °C and pH 4, the formation of millerite in addition to violarite resulted in faster porosity coarsening and formed micropores within 4 weeks.
Fundamentally, these complex porosity creation and evolution phenomena observed in the two model mineral replacement reactions are controlled by the interplay between dissolution, precipitation, epitaxial nucleation, and Ostwald ripening processes which are all sensitive to reaction conditions. This understanding should generally be applicable to other mineral replacement reactions.
Finally, a case study of the application of porosity control was presented. The leaching of chalcopyrite is often kinetically inhibited by surface passivation layers, which are formed by the replacement of chalcopyrite during leaching. Common passivation layers are elemental sulphur and jarosite. Our leaching experimental results showed that surface sulphur could be removed by adding sulphur-dissolving solvent tetrachloroethylene (TCE) into the sulfuric acid leaching solution. The removal of surface sulphur significantly improved the leaching rate by almost 6 times compared with TCE-free leaching. At the later stage of leaching, chalcopyrite was replaced by potassium jarosite. The jarosite shell did not passivate TCE-free leaching due to its porous structure. However, the jarosite shell became nearly impermeable in TCE-assisted leaching because elemental sulphur filled the pores in the jarosite. This case study suggests that chalcopyrite leaching can be significantly enhanced by either removing the surface passivating layer or by controlling the porosity and permeability of the surface layers formed on the chalcopyrite surface
English-learning motivation among Chinese mature learners: A comparative study of English and non-English majors
Get PDFThis study examined the motivation of Chinese mature students toward learning English. The participants in the study were ten Chinese mature learners, of whom four were English majors and six were non-English majors. Each underwent a semi-structured interview. Their responses were then coded and analyzed based on Matsuzaka-Carreira’s motivation framework. Furthermore, the Keyword Extraction and Link Terms techniques of PolyAnalystTM were used for further analysis. The results showed that English majors tended to be goal-oriented, and non-English majors were more likely to be means-oriented. English majors were identified as having additional integrative motivation. The factors influencing the motivation of English majors were more diverse than those influencing their non-English major counterparts. The obvious distinction between the two groups was their attitude towards the target language and culture. These findings suggest that instruction for adults should be aligned with mature learners’ practical needs and individual characteristics
Momma needs a drink: Droughts are stressing out pregnant snakes
Get PDFMothers invest a lot of time into the healthy development of their young. Yet, climate change is making motherhood more challenging. Water and nutrients are becoming scarce. Indeed, a recent study, led by Mathias Dezetter from the Centre for Biological Studies of Chizé in France, found that snakes are no exception. Populations of European adder (Vipera berus) may ‘dry out’ if drought conditions worsen..