AbstractThis paper presents the behavior of amorphous metallic fiber (AMF)–reinforced geopolymer composites under compression, bending, and uniaxial tension loads. Comparison is also made with ...counterpart cement composites reinforced by AMF and steel fiber (SF)–reinforced geopolymer composites. In this study four series of composites were considered in two parts. In the first part, heat cured geopolymer (HCG) composites reinforced by 0.5%, 1.0%, and 1.5% (by volume) AMF were considered in one series, while similar volume fractions of AMF were used to reinforce conventional cement composite in another series to benchmark the observed properties. In the second part, similar volume fractions of AMF were used to reinforce ambient air cured geopolymer (ACG) composites, and the results were benchmarked with conventional SF-reinforced ACG composites. The water to cement ratio and alkali activator to binder ratios in all composites were kept constant for comparison, and all composites were tested after 28 days of curing. The results showed that the compressive strength of AMF-reinforced HCG composites was higher than that of AMF-reinforced cement and AMF-reinforced ACG composites. However, the compressive strength of SF-reinforced cement composites was slightly higher than that of AMF-reinforced ACG composites. Regardless of composite and fiber types, an increasing trend in compressive strength with an increase in the volume fraction of fibers was also observed. The results also showed higher flexural and tensile strengths for AMF-reinforced HCG composites than for counterpart cement composites. The flexural and tensile strengths of both geopolymer composites also increased with an increase in AMF volume fraction. However, both flexural and tensile strengths were higher for ACG composites when reinforced by SF than when reinforced by AMF. Microstructural observations through scanning electron microscopy showed no damage of the AMF and SF in the geopolymer composites and showed higher amounts of geopolymer matrix on the surface of AMF in HCG composites than in cement and ACG composites.
In the broader American foreign policy community, there is an intense ongoing debate on how strong the push-back against China should be. Both moderates and hawks agree on the need for a "tougher" ...approach but differ on the degree and method of toughness. No coherent strategy has been possible partly because President Trump's thinking does not always accord with that of his own administration and partly because it is still too early in the day to come out with well-thought-out policies to support such a major change in foreign policy direction.
Prunus cerasoides
is a traditionally well known for human health in various ways and particularly its bark is reported to possess high therapeutic applications in wound healing, foot and mouth ...disease, and indigestion etc. But there is scanty literature available on its systematic studies and phytoconstituents responsible for antimicrobial activity so the work is proposed. The main aim of this study is to reveal the phytoconstituents responsible for antimicrobial and antibiofilm action to demonstrate the effectiveness of such compounds by extrapolating the data using clinical isolates of pathogenic bacteria. In the present study, evaluation of
P. cerasoides
organic extract and phytoconstituents for their antimicrobial and antibiofilm potential against reference microbial strains was carried out. Antimicrobial potential was carried out using agar diffusion assay and biosafety of organic extract and its phytoconstituents was evaluated by MTT and Ames mutagenicity assay. Ethyl acetate was found to be the best organic extractant, where
Klebsiella pneumoniae
1 (39.5 mm) and
Staphylococcus aureus
(22.5 mm) were the most sensitive microorganisms, respectively. Among the major phytoconstituents, flavonoids (14.5–33.5mm), diterpenes (14–28.7 mm), and cardiac glycosides (11.5–20.5mm) exhibited broad-spectrum antimicrobial activity. Ethyl acetate extract showed better potency with lowest minimum inhibitory concentration (0.1–10 mg/ml) than the most active partially purified phytoconstituents (0.5–10 mg/ml). Total activity potency for ethyl acetate extract ranged from 26.66–2666 ml/g and for flavonoids, it was 41–410 ml/g, thus considered as highly potent and bactericidal in nature as evidenced from VCC study. The major bioactive compounds were found to be biosafe. The most active phytoconstituents were found to have antibiofilm potential, as well as effective against clinical isolates of MRSA, thus, the findings indicate that
P. cerasoides
stem bark could be a potential source for development of broad-spectrum drugs against multidrug-resistant bugs.
Studies have found that urban environments have a negative impact on physical and mental health. This is due to urban stressors such as increased noise levels, higher crime rates and rampant ...pollution. Moreover, living in building-dominant surroundings increases stress levels. There’s growing scientific evidence that forest therapy is a cost-effective method of stress management, and also has the ability to improve physical and mental wellbeing. The concept of forest therapy was first developed by the Japanese Forestry Agency in 1982, where it is known as “shinrin-yoku”. Over the years, there has been growing interest in forest therapy research. These studies usually focus on forest therapy’s effects on human health, from physiological and psychosocial perspectives, but there are also studies on its potential in treating specific illnesses such as hypertension and depression. By analysing current research frameworks, methodologies and research findings, we would gain a better insight and understanding of forest therapy; Allowing researchers, medical professionals and the general public to fully utilize this cost-effective form of preventative medicine. Therefore, the core objective of this review paper is to provide: a) An in-depth analysis of current forest therapy research, from physiological and psychosocial perspectives, b) To provide a systematic summary of current forest therapy research and c) To encourage healthcare professionals and the general public to fully utilize forest therapy as a form of preventive medicine. We reviewed current literature on forest therapy (2010–2020) using two electronic databases (ScienceDirect and PubMed), and selected 27 articles for this review. Based on the research data, we believe that forest therapy plays an important role in preventive medicine and stress management for all age groups. However, there is a need for more research on its sustained effects and for multi-disciplinary studies, especially with healthcare professionals.
The present study was aimed to isolate the endophytic fungi having antimicrobial potential from
Moringa oleifera
. Out of the active isolates, the endophytic fungal isolate DSE 17 obtained from the ...bark of the plant was selected for further studies and identified as
Aspergillus fumigatus
. The classical method for optimization strategy revealed inoculum size of four discs in Czapek dox’s medium at a temperature of 25 °C and pH 7 with the incubation period of 6 days to be the best. Sucrose as carbon source (1%) and sodium nitrate as nitrogen source (0.2%) were found to be the best for antimicrobial activity. Response surface methodology was effective in optimizing the selected medium components in Plackett–Burman design, i.e. magnesium sulphate, dipotassium phosphate and sodium nitrate, which resulted in increase in antimicrobial activity by 1.7-fold. Chloroform was found to be the best extractant amongst different solvents. The minimum inhibitory concentration (MIC) values of the chloroformic extract ranged from 0.05 to 0.5 mg/ml, and the viable cell count studies revealed it to be bactericidal in its nature. The post-antibiotic effect (PAE) of the chloroformic extracts ranged from 2 to 20 h. Ames mutagenicity testing and MTT assay revealed the crude extract neither cytotoxic nor mutagenic, thus showing it to be biosafe. Thus, the study suggests that endophytes from this miracle plant could be potential source for the production of broad-spectrum antimicrobial compound/s.
Plant height is an important morphological and developmental phenotype that directly indicates overall plant growth and is widely predictive of final grain yield and biomass. Currently, manually ...measuring plant height is laborious and has become a bottleneck for genetics and breeding programs. The goal of this research was to evaluate the performance of five different sensing technologies for field-based high throughput plant phenotyping (HTPP) of sorghum
(L.) Moench height. With this purpose, (1) an ultrasonic sensor, (2) a LIDAR-Lite v2 sensor, (3) a Kinect v2 camera, (4) an imaging array of four high-resolution cameras were evaluated on a ground vehicle platform, and (5) a digital camera was evaluated on an unmanned aerial vehicle platform to obtain the performance baselines to measure the plant height in the field. Plot-level height was extracted by averaging different percentiles of elevation observations within each plot. Measurements were taken on 80 single-row plots of a US × Chinese sorghum recombinant inbred line population. The performance of each sensing technology was also qualitatively evaluated through comparison of device cost, measurement resolution, and ease and efficiency of data analysis.
We found the heights measured by the ultrasonic sensor, the LIDAR-Lite v2 sensor, the Kinect v2 camera, and the imaging array had high correlation with the manual measurements (
≥ 0.90), while the heights measured by remote imaging had good, but relatively lower correlation to the manual measurements (
= 0.73).
These results confirmed the ability of the proposed methodologies for accurate and efficient HTPP of plant height and can be extended to a range of crops. The evaluation approach discussed here can guide the field-based HTPP research in general.
Novel high-throughput phenotyping (HTP) approaches are needed to advance the understanding of genotype-to-phenotype and accelerate plant breeding. The first generation of HTP has examined simple ...spectral reflectance traits from images and sensors but is limited in advancing our understanding of crop development and architecture. Lodging is a complex trait that significantly impacts yield and quality in many crops including wheat. Conventional visual assessment methods for lodging are time-consuming, relatively low-throughput, and subjective, limiting phenotyping accuracy and population sizes in breeding and genetics studies. Here, we demonstrate the considerable power of unmanned aerial systems (UAS) or drone-based phenotyping as a high-throughput alternative to visual assessments for the complex phenological trait of lodging, which significantly impacts yield and quality in many crops including wheat. We tested and validated quantitative assessment of lodging on 2,640 wheat breeding plots over the course of 2 years using differential digital elevation models from UAS. High correlations of digital measures of lodging to visual estimates and equivalent broad-sense heritability demonstrate this approach is amenable for reproducible assessment of lodging in large breeding nurseries. Using these high-throughput measures to assess the underlying genetic architecture of lodging in wheat, we applied genome-wide association analysis and identified a key genomic region on chromosome 2A, consistent across digital and visual scores of lodging. However, these associations accounted for a very minor portion of the total phenotypic variance. We therefore investigated whole genome prediction models and found high prediction accuracies across populations and environments. This adequately accounted for the highly polygenic genetic architecture of numerous small effect loci, consistent with the previously described complex genetic architecture of lodging in wheat. Our study provides a proof-of-concept application of UAS-based phenomics that is scalable to tens-of-thousands of plots in breeding and genetic studies as will be needed to uncover the genetic factors and increase the rate of gain for complex traits in crop breeding.
' Southeast Asian Affairs , first published in 1974, continues today to be required reading for not only scholars but the general public interested in in-depth analysis of critical cultural, economic ...and political issues in Southeast Asia. In this annual review of the region, renowned academics provide comprehensive and stimulating commentary that furthers understanding of not only the region's dynamism but also of its tensions and conflicts. It is a must read.' - Suchit Bunbongkarn, Emeritus Professor, Chulalongkorn University
'Now in its fiftieth edition, Southeast Asian Affairs offers an indispensable guide to this fascinating region. Lively, analytical, authoritative, and accessible, there is nothing comparable in quality or range to this series. It is a must read for academics, government officials, the business community, the media, and anybody with an interest in contemporary Southeast Asia. Drawing on its unparalleled network of researchers and commentators, ISEAS is to be congratulated for producing this major contribution to our understanding of this diverse and fast-changing region, to a consistently high standard and in a timely manner.' - Hal Hill, H.W. Arndt Professor Emeritus of Southeast Asian Economies, Australian National University
This study presents a life cycle assessment (LCA) of end-of-life (EoL) photovoltaic (PV) systems in Australia. Three different EoL scenarios are considered for 1 kWh of electricity generation across ...a 30-year PV system lifespan: (i) disposal to landfill, (ii) recycling by laminated glass recycling facility (LGRF), and (iii) recycling by full recovery of EoL photovoltaics (FRELP). It is found that recycling technologies reduce the overall impact score of the cradle-to-grave PV systems from 0.00706 to 0.00657 (for LGRF) and 0.00523 (for FRELP), as measured using the LCA ReCiPe endpoint single score. The CO2 emissions to air decrease slightly from 0.059 kg CO2 per kWh (landfill) to 0.054 kg CO2 per kWh (for LGRF) and 0.046 kg CO2 per kWh (for FRELP). Increasing the PV system lifespan from 30 years to 50 and 100 years (a hypothetical scenario) improves the ReCiPe endpoint single-score impact from 0.00706 to 0.00424 and 0.00212, respectively, with corresponding CO2 emissions reductions from 0.059 kg CO2 per kWh to 0.035 and 0.018 kg CO2 per kWh, respectively. These results show that employing recycling slightly reduces the environmental impact of the EoL PV systems. It is, however, noted that recycling scenarios do not consider the recycling plant construction step due to a lack of data on these emerging PV panel recycling plants. Accounting for the latter will increase the environmental impact of the recycling scenarios, possibly defeating the purpose of recycling. Increasing the lifespan of the PV systems increases the longevity of the use of panel materials and is therefore favorable towards reducing environmental impacts. Our findings strongly suggest that PV recycling steps and technologies be carefully considered before implementation. More significantly, it is imperative to consider the circular design step up front, where PV systems are designed via circular economy principles such as utility and longevity and are rolled out through circular business models.
A family of seven silver(I)‐perfluorocarboxylate‐quinoxaline coordination polymers, Ag4(O2CRF)4(quin)4 1–5 (RF=(CF2)n‐1CF3)4, n=1 to 5); Ag4(O2C(CF2)2CO2)2(quin)4 6; Ag4(O2CC6F5)4(quin)4 7 ...(quin=quinoxaline), denoted by composition as 4 : 4 : 4 phases, was synthesised from reaction of the corresponding silver(I) perfluorocarboxylate with excess quinoxaline. Compounds 1–7 adopt a common 2D layered structure in which 1D silver‐perfluorcarboxylate chains are crosslinked by ditopic quinoxaline ligands. Solid‐state reaction upon heating, involving loss of one equivalent of quinoxaline, yielding new crystalline 4 : 4 : 3 phases Ag4(O2C(CF2)n‐1CF3)4(quin)3n (8–10, n=1 to 3), was followed in situ by PXRD and TGA studies. Crystal structures were confirmed by direct syntheses and structure determination. The solid‐state reaction converting 4 : 4 : 4 to 4 : 4 : 3 phase materials involves cleavage and formation of Ag−N and Ag−O bonds to enable the structural rearrangement. One of the 4 : 4 : 3 phase coordination polymers (10) shows the remarkably high dielectric constant in the low electric field frequency range.
Two‐dimensional coordination polymers exhibit ligand extrusion into the vapour phase on heating to undergo an extensive structural reorganisation involving bond breaking and formation, ligand migration and reorientation. The reactions occur with retention of crystallinity and have been followed in situ by PXRD.
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