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Low-Risk penicillin allergy delabeling through direct oral challenge in immunocompromised and/or multiple drug allergy labeled patients in a critical care setting
No full textDiet of dingoes in the West Kimberley, and the impact of linear clearing
No full textGeneralist predators, such as the dingo (Canis familiaris), frequently use linear clearings as movement corridors, increasing their mobility, landscape access, and sometimes modifying predator–prey relationships. We quantified the diet of the dingo in the West Kimberley region of Western Australia and tested the hypothesis that clearing of seismic lines would result in a change to the diet of dingoes. A total of 199 scats were collected from inside and outside the footprint of a seismic survey at three collection time points (before and twice after the disturbance). Overall, the diet of dingoes varied over seasons (P = 0.003), and between control and treatment sites (P = 0.013); however, there was no evidence of a shift in diet caused by seismic clearing (time × treatment interaction term, P = 0.848). Cattle were the most frequently occurring item (frequency of occurrence = 65% of 199 samples; the greatest value recorded in Australia), with greater consumption of cattle in control and treatment sites at the end of the dry season compared to the early dry season, likely driven by an increase in cattle mortality and susceptibility to predation. Despite dingoes using seismic lines as movement corridors, there is little evidence that this results in a change in their diet
Novel 3′-[4-fluoroaryl-(1,2,3-triazol-1-yl)]-3′-deoxythymidine analogues: Design, synthesis, characterization and their potential as anticancer agents
No full textNovel 3′-[4-fluoroaryl-(1,2,3-triazol-1-yl)]-3′-deoxythymidine analogues (7a-l) were developed by the Cu alkyne-azide cycloaddition (CuAAC) reaction. The obtained lead compounds were confirmed by using 1H NMR, 13C NMR, 2 D NMR, HRMS and their anticancer activities were screened against Huh-7 liver cancer cells and U87MG human glioblastoma cells. Among the synthesized fluorinated 1,2,3-triazolyl nucleosides, three compounds (7i, 7a-b) demonstrated promising anti-proliferative against Huh-7 and U87MG cell lines. Significantly, compound 7i has displayed remarkable promising anticancer activity with IC50 value in the micromole range (22.41–24.92 µM) and (18.12–21.36 µM) against Huh-7 cancer cells and U87MG glioblastoma cells, respectively
Phosphorus supply affects seedling growth of mycorrhizal but not cluster-root forming jarrah-forest species
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Fertiliser is often used to kick-start ecological restoration despite growing evidence of the potentially negative impacts on plant diversity. Jarrah (Eucalyptus marginata) forest species growing on nutrient (especially phosphorus) impoverished soils in southwestern Australia have a suite of adaptations for phosphorus (P) acquisition, including the formation of cluster roots, and associations with mycorrhizal fungi. Here we investigated how escalating P supply, along with a stoichiometric adjustment of nitrogen (N) supply, impacted the growth and nutrition of a wide range of jarrah forest seedlings.
Methods
In a pot experiment, we measured seedling biomass and nutritional responses of 12 jarrah forest species to a gradient of P supply in relation to N supply, and for the mycorrhizal species, inoculation with arbuscular mycorrhizal fungi.
Results
Three cluster-root forming species did not respond to increasing P, probably because they were reliant on seed P. Generally, mycorrhizal species showed a positive biomass response to increasing P when N was available. Mycorrhizas benefited seedling growth at low P (9 mg P added per kg of jarrah forest soil) when N was also available, and were parasitic to seedling growth at high P (243 mg P/ kg soil) without additional N.
Conclusions
These results highlight importance of P and N supply in determining the nature of the symbiosis between plants and mycorrhizal fungi. Since P supply has the potential to reduce plant growth, for a range of species, our results suggest careful consideration of fertiliser amounts for ecological restoration of ecosystems adapted to nutrient poor soils
Diversity and patterns of marine non‐native species in the archipelagos of Macaronesia
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The present study is the first attempt to grasp the scale and richness of marine biological invasions in Macaronesia. We pioneered a comprehensive non-native species (NNS), inventory in the region to determine their diversity patterns and native distribution origins. NNS were defined here as the result of both introductions and range expansions. We also used statistical modelling to examine relationships among NNS richness, anthropogenic activities, demographic and geographical variables across Macaronesia.
Location
Macaronesia.
Methods
A comprehensive literature search was conducted for marine NNS records in Macaronesia, registering the first record's location and year from 1884 to 2020. We used univariate and multivariate analyses to evaluate differences and similarities in community composition. By applying a Generalized Linear Model (GLM), we tested hypotheses regarding NNS richness as a function of anthropogenic activities, demographic and geographical variables.
Results
A total of 144 marine non-native species (NNS) were recorded for the whole of Macaronesia. The highest NNS richness was registered in the Canary Islands (76 NNS), followed by the Azores (66 NNS), Madeira (59 NNS) and finally Cabo Verde (18 NNS). Some differences amongst archipelagos were observed, such as the high number of non-native macroalgae in the Azores, fishes in the Canary Islands and tunicates in Cabo Verde. Overall, macroalgae, tunicates and bryozoans were the predominant taxonomic groups in the Macaronesian archipelagos. Madeira and Canary Islands were the archipelagos with more similarity in marine NNS, and Cabo Verde the most divergent. Finally, GLM suggested that non-native richness patterns across Macaronesia were dependent on the considered archipelago and strongly affected by (1) minimum distance to the mainland, (2) the total number of ports and marinas and (3) total marinas area (km2).
Conclusions
The model results and NNS listing in the present study will likely raise the awareness and response regarding marine NNS in the whole Macaronesia region, serving as a baseline for future research as well as implementing and enforcing regulations related to the introduction of marine NNS in oceanic islands
Differential responses of the rhizosphere microbiome structure and soil metabolites in tea (Camellia sinensis) upon application of cow manure
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The rhizosphere is the narrow zone of soil immediately surrounding the root, and it is a critical hotspot of microbial activity, strongly influencing the physiology and development of plants. For analyzing the relationship between the microbiome and metabolome in the rhizosphere of tea (Camellia sinensis) plants, the bacterial composition and its correlation to soil metabolites were investigated under three different fertilization treatments (unfertilized, urea, cow manure) in different growing seasons (spring, early and late summer).
Results
The bacterial phyla Proteobacteria, Bacteroidetes, Acidobacteria and Actinobacteria dominated the rhizosphere of tea plants regardless of the sampling time. These indicated that the compositional shift was associated with different fertilizer/manure treatments as well as the sampling time. However, the relative abundance of these enriched bacteria varied under the three different fertilizer regimes. Most of the enriched metabolic pathways stimulated by different fertilizer application were all related to sugars, amino acids fatty acids and alkaloids metabolism. Organic acids and fatty acids were potential metabolites mediating the plant-bacteria interaction in the rhizosphere. Bacteria in the genera Proteiniphilum, Fermentimonas and Pseudomonas in spring, Saccharimonadales and Gaiellales in early summer, Acidobacteriales and Gaiellales in late summer regulated relative contents of organic and fatty acids.
Conclusion
This study documents the profound changes to the rhizosphere microbiome and bacterially derived metabolites under different fertilizer regimes and provides a conceptual framework towards improving the performance of tea plantations
Genome-wide superior alleles, haplotypes and candidate genes associated with tolerance on sodic-dispersive soils in wheat (Triticum aestivum L.)
Get PDFSodic-dispersive soils have multiple subsoil constraints including poor soil structure, alkaline pH and subsoil toxic elemental ion concentration, affecting growth and development in wheat. Tolerance is required at all developmental stages to enhance wheat yield potential on such soils. An in-depth investigation of genome-wide associations was conducted using a field phenotypic data of 206 diverse Focused Identification of Germplasm Strategy (FIGS) wheat lines for two consecutive years from different sodic and non-sodic plots and the exome targeted genotyping by sequencing (tGBS) assay. A total of 39 quantitative trait SNPs (QTSs), including 18 haplotypes were identified on chromosome 1A, 1B, 1D, 2A, 2B, 2D, 3A, 3B, 5A, 5D, 6B, 7A, 7B, 7D for yield and yield-components tolerance. Among these, three QTSs had common associations for multiple traits, indicating pleiotropism and four QTSs had close associations for multiple traits, within 32.38 Mb. The overlapping metal ion binding (Mn, Ca, Zn and Al) and photosynthesis genes and transcription factors (PHD-, Dof-, HTH myb-, BHLH-, PDZ_6-domain) identified are known to be highly regulated during germination, maximum stem elongation, anthesis, and grain development stages. The homozygous/biallelic SNPs having allele frequency above 30% were identified for yield and crop establishment/plants m−2. These SNPs correspond to HTH myb-type and BHLH transcription factors, brassinosteroid signalling pathway, kinase activity, ATP and chitin binding activity. These resources are valuable in haplotype-based breeding and genome editing to improve yield potential on sodic-dispersive soils
Weapons of choice: A statistical comparison between different weapons and resulting injuries, opportunist weapon selection and forensic awareness
Get PDFHomicide is a known term for the unlawful killing of another person, which can be classified into three subcategories; Mass, Spree and Serial Homicide. Serial Homicide is the chosen focus for this literature review, and the following study to come. A Serial Killer can be described as an individual who takes the life of at least two people, each within a separate event to one another. Specifically, the weapons of choice by these Serial Killers is the main concentration of the study, and how different external variables can change their choosing, as well as the resulting injuries the victim sustains from these weapons. Variables such as victimology of both the offender and the victim, the level of forensic awareness known by the offender and whether the weapon was an opportunist circumstance or not are detailed to identify the changes in weapon choice and injury infliction as these variables change between offenders. The literature review aims to display what information is already present in the field, with the relation of all factors in weapon choice and injuries and if there is already a link between any. The review ultimately defined that there is a big gap in research about weapons of opportunity and the factors which can cause an offender to use an unplanned weapon to cause injury, as well as how the injuries differ between opportunity and planned weapon selection. The review also revealed there is an obvious gap in knowledge linking all of these mentioned variables, to the way the offender inflicts injuries on the victim. The proposed study will hopefully fill these research gaps by comparing victimology, opportunity and planned weapons, forensic awareness knowledge and clean-up to the type of weapon used and the resulting injuries, the hope is to link them all together, as well as identify individual characteristics of each which can change offenders weapon selection
Sliding Schottky diode triboelectric nanogenerators with current output of 109 A/m2 by molecular engineering of Si(211) surfaces
No full textTriboelectric nanogenerators (TENGs) are an autonomous and sustainable power-generation technology, seeking to harvest small vibrations into electricity. Here, by achieving molecular control of oxide-free Si crystals and using conductive atomic force microscopy, we address key open questions and use this knowledge to demonstrate zero-applied-bias current densities as high as 109 A/m2. Key to achieve this output, is to use a proton-exchangeable organic monolayer that simultaneously introduces a sufficiently high density of surface states (assessed as changes to carrier recombination velocities) coupled to a strong surface dipole in the form of a surface alkoxide anion (Si–monolayer–O−). We also demonstrate that the DC output of a Schottky diode TENG does not track the energy released as friction. This removes the complexity of controlling an unavoidable stick–slip motion, bypassing the requirement of aligning sliding motion and substrate topographical features. We reveal that there is no apparent correlation between the current of a static (biased) junction and the tribocurrent of the same junction when under motion and unbiased
Varying climatic-social-geographical patterns shape the conflict risk at regional and global scales
Get PDFGiven that armed conflict has been seriously impeding sustainable development, reducing the frequency and intensity of armed conflicts has become an explicit goal and a common theme of the 2030 Sustainable Development Goals. Determining the factors shaping armed conflict risks in different regions could support formulating region-specific strategies to prevent armed conflicts. A machine learning approach was applied to reveal the drivers of, and especially the impact of climatic conditions on, armed conflict in Sub-Saharan Africa, the Middle East, and South Asia and characterizes their changes over time. The analyses show a rising impact of climatic conditions on armed conflict risk over the past decades, although the influences vary regionally. The overall percentage increases in the contribution of climatic conditions to conflict risks over the last 30 years in Sub-Saharan Africa, the Middle East, and South Asia are 4.25, 4.76, and 10.65 percentage points, respectively. Furthermore, it is found that the Climatic–Social–Geographical (“C–S–G”) patterns that characterize armed conflict risks vary across the three studied regions, while each regional pattern remains relatively stable over time. These findings indicate that when devising defenses against conflicts, it is required to adapt to specific situations in each region to more effectively mitigate the risk of armed conflict and pursue Sustainability Development Goals