61871 research outputs found
Sort by
The tube-web spiders of the genus Ariadna (Araneae: Segestriidae) from South Australia and Victoria
Full text linkThe tube-web spider genus Ariadna Audouin, 1826 has been revised for South Australia and Victoria, revealing a remarkable diversity, particularly centred in the arid north of South Australia. We describe 23 species as new, ten of which are supported by molecular data, where these were available. We recognise two species groups for some of the species based on a combination of genitalic morphology, macrosetae patterns and somatic characters: the clavata species group, which includes Ariadna clavata Marsh, Baehr, Glatz & Framenau, 2018 and A. spinosa sp. nov. from South Australia, and A. otwayensis sp. nov. and A. sinuosa sp. nov. from Victoria, and the formosa species group, including A. formosa sp. nov. and A. umbra sp. nov. from South Australia, and A. tria sp. nov. from Victoria. Seventeen new species could not be placed into these two species groups: A. arenacea sp. nov., A. bellatula sp. nov., A. curvata sp. nov., A. deserta sp. nov., A. diucrura sp. nov., A. flavescens sp. nov., A. inflata sp. nov., A. insula sp. nov., A. pollex sp. nov., A. propria sp. nov., A. rutila sp. nov., Ariadna simplex sp. nov., A. subplana sp. nov., A. una sp. nov., A. ungua sp. nov., A. valida sp. nov. and A. woinarskii sp. nov. We provide updated diagnoses and distributional data for A. clavata and A. tangara Marsh, Baehr, Glatz & Framenau, 2018; however, the holotype of A. burchelli (Hogg, 1900) from Victoria could not be located for this project
A comparison of lead-based and lead-free bullets for shooting sambar deer (Cervus unicolor) in Australia
Full text linkContext: In response to the toxic health threats posed by lead (Pb), there is currently a focus on transitioning to lead-free bullets for shooting wild animals.
Aim: We aimed to quantify the killing efficiency and animal welfare outcomes of lead-based and lead-free (copper-based) bullets for ground-based shooting of sambar deer (Cervus unicolor) in Victoria, south-eastern Australia.
Methods: We used shooter-collected data from recreational diurnal hunting and professional nocturnal culling during 2020–2021. Shooters recorded rifle calibre, cartridge type, bullet mass, bullet type, shooting outcomes (miss, wound or kill), shooting distance, flight distance (the distance between where the animal was shot and where it died) as an assumed positive correlate of time to incapacitation, anatomical zones struck by bullets, and frequency of bullet exit wounds. We used flight distance as our response variable, assuming that it is positively correlated with time to incapacitation. To examine the role of several predictor variables (including bullet type) potentially influencing flight distance, the dataset was reduced to those deer killed with a single thoracic shot.
Key results: Our data captured shooting events involving 276 deer, with 124 deer shot at with lead-based bullets and 152 with copper-based bullets. Most (87%) of the deer were killed with a single shot. The frequency of non-fatal wounding was <4% for both bullet types and there was no distinct difference in the probability of a single shot kill for deer shot with either bullet type. For those deer killed with a single thoracic shot (n = 198), there was no evidence that bullet energy or shooting distance influenced flight distance. After accounting for differences in terminal kinetic energy, the mean flight distance of deer shot with lead-free bullets (35 m) was 56% greater than that of deer shot with lead-based bullets (22 m).
Conclusions: Lead-based and lead-free bullets produced similar animal welfare outcomes for shooting sambar deer.
Implications: A transition to lead-free ammunition for shooting sambar deer would have minimal impact on efficiency or animal welfare outcomes
Exercise medicine for cancer cachexia: targeted exercise to counteract mechanisms and treatment side effects
Full text linkPurpose
Cancer-induced muscle wasting (i.e., cancer cachexia, CC) is a common and devastating syndrome that results in the death of more than 1 in 5 patients. Although primarily a result of elevated inflammation, there are multiple mechanisms that complement and amplify one another. Research on the use of exercise to manage CC is still limited, while exercise for CC management has been recently discouraged. Moreover, there is a lack of understanding that exercise is not a single medicine, but mode, type, dosage, and timing (exercise prescription) have distinct health outcomes. The purpose of this review was to examine the effects of these modes and subtypes to identify the most optimal form and dosage of exercise therapy specific to each underlying mechanism of CC.
Methods
The relevant literatures from MEDLINE and Scopus databases were examined.
Results
Exercise can counteract the most prominent mechanisms and signs of CC including muscle wasting, increased protein turnover, systemic inflammation, reduced appetite and anorexia, increased energy expenditure and fat wasting, insulin resistance, metabolic dysregulation, gut dysbiosis, hypogonadism, impaired oxidative capacity, mitochondrial dysfunction, and cancer treatments side-effects. There are different modes of exercise, and each mode has different sub-types that induce vastly diverse changes when performed over multiple sessions. Choosing suboptimal exercise modes, types, or dosages can be counterproductive and could further contribute to the mechanisms of CC without impacting muscle growth.
Conclusion
Available evidence shows that patients with CC can safely undertake higher-intensity resistance exercise programs, and benefit from increases in body mass and muscle mass
The impact of steric repulsion on the total free energy of electric double layer capacitors
No full textWe present an analysis of the total free energy of a supercapacitor modelled with a composite diffuse layer (CDL) formed by a steric repulsive potential. The steric potential is modelled with a simple approximation to the Bikerman steric potential, enabling derivation of an analytical expression for the total free energy of the supercapacitor in terms of the size and valency of the electrolyte counterions and electrode potentials. The analytical expression for the total free energy of the supercapacitor matches the exact numerical Bikerman calculation at high potential with relative error close to 1%. This provides an upper bound over the more accurate Carnahan-Starling model. A maximum upper bound for the energy is also provided in the limit where bulk concentrations approach the ion concentration cap. We analyze the relative contribution of the steric interaction to the total free energy. At large voltages, the steric free energy is comparable in magnitude to that of the electrostatic free energy, and introduces ion-size effects in the energy of the supercapacitor. Consequently at high potentials the total free energy exceeds (doubles) the classical energy , indicating that this formula does not correctly describe the available stored energy from the experimentally measured capacitance
It’s all about politics: Migration and resource conflicts in the global south
No full textBoth researchers and policy makers have repeatedly expressed concerns that migration will enhance conflicts regarding renewable resources in destination areas. This concept is fuelled by projections of large future migration flows within the Global South, resulting from armed conflict, global environmental change, and persistent economic inequalities. However, as of yet, there is no conclusive empirical evidence of a nexus between migration, resource competition, and conflict at an aggregate level. Case studies draw contradicting conclusions, and cross-case research on the topic remains scarce. Here, we combine comprehensive qualitative and quantitative data from 20 cases in rural Asia, Latin America and Sub-Saharan Africa. Based on these cases, we investigate why certain areas hosting migrants have resource-related conflicts, while others do not. Using qualitative comparative analysis (QCA), we evaluate and elucidate two combinations of conditions under which resource conflict involving migrants in destination areas occurs: (1) high reliance on natural resources and negative othering of migrants in terms of resource use, and (2) government policies supporting parts of the migrant group coupled with limited resource use possibilities due to conservation efforts or industrial activities. By underlining the crucial role of grievances related to perceived unfair resource access and the strong influence of government actions on local migrant-host dynamics, we challenge deterministic narratives of migration, resource scarcity and conflict
Relation-aware collaborative autoencoder for personalized multiple facet selection
No full textCollaborative-based personalization has been one of the most successful techniques used in building personalization for recommender systems and facet selection. The technique predicts users’ interests based on the preferences of similar people or items. The prediction is usually made on one single group of users or items/facets. However, multiple facet selection creates a different challenge where the prediction needs to be based on the similarity among different groups of users and facets. In conventional collaborative approach, user–facet representation is created from the concatenation of user preferences on each facet. This creates a spared representation which affects the accuracy of the personalized model. It is essential to develop a more suitable representation that effectively represents the collaborative preferences given across multiple facets and a predictive model to estimate the possible preferences across those groups. Multiple facets appear to be correlated to each other and this can be useful for associating the existing preferences. None of the previous works has addressed the issue due to the association of facet relationships. Hence, this paper aims to examine the effectiveness of a new approach that utilizes multiple-facet relationships to associate the collaborative interests across different facets. This study proposes a new collaborative-based personalization model for multiple facet selection, called Relation-aware Collaborative Autoencoder (RCAE) Model. A new embedding methodology was introduced for incorporating multiple facet relationships into user–facet interaction. Evaluations based on four real-world datasets demonstrated that the proposed model utilizing facet relationships has achieved significant improvement over the conventional collaborative approach
Uninterrupted path planning system for Multi-USV sampling mission in a cluttered ocean environment
No full textThis paper presents an uninterrupted collision-free path planning system that facilitates the operational performance of multiple unmanned surface vehicles (USVs) in an ocean sampling mission. The proposed uninterrupted path planning system is developed based on the integration of a novel B-Spline data frame and particle swarm optimization (PSO)-based solver engine. The new B-spline data framing structure provides smart sampling of the candidate spots without needing full stop for completing the sampling tasks. This enables the USVs to encircle the area smoothly while simultaneously correcting the heading angle toward the next spot and preventing sharp changes in the vehicle's heading. Then, the optimization engine generates optimal, smooth, and constraint-aware path curves for multiple USVs to conduct the sampling mission from start point to the rendezvous point. The path generated incorporates controllability over the vehicles' velocity profile to prevent experiencing zero velocity and frequent stop/start switching of the controller. To achieve faster convergence of the optimization routine, a suitable search space decomposition scheme is proposed. Extensive simulation studies emulating a realistic ocean sampling mission are conducted to examine the feasibility and effectiveness of the proposed path planning system. This encapsulates modelling a realistic maritime environment of Indonesian Archipelago in Banda Sea including ocean waves, obstacles, and no-fly zones and introducing several performance indices to benchmark the path planning system performance. This process is accompanied by a comparative study of the proposed path planning system with a well-known state-of-the art piecewise, rapidly exploring random tree (RRT), and differential evolution-based path planning algorithms. The results of the simulation confirm the suitability and robustness of the proposed path planning system for the uninterrupted ocean sampling missions
Beneficial effect of iron oxide/hydroxide minerals on sulfuric acid baking and leaching of monazite
No full textThe sulfuric acid bake/leach process is an established industrial process for the extraction of rare earths from hard-rock monazite ores/concentrates. The chemical reactions in the monazite acid bake can be strongly influenced by the gangue mineralogy of the ore/concentrate. In this work, the beneficial effect of three iron oxide/hydroxide minerals, namely hematite, goethite and magnetite, added to high grade monazite concentrate in the acid bake (temperature range of 200–800°) and leach process was investigated to understand the role of iron gangue. Baked solids and leach residues were characterised by elemental analyses, XRD, SEM-EDS and FT-IR. It was found that the addition of iron minerals to the monazite acid bake had a significant impact on bake chemistry, acting to significantly increase the leaching of both the rare earth elements and thorium, compared to monazite alone, mainly for temperatures above 300 °C. The increased dissolution of rare earth elements and thorium was attributed to the formation of an amorphous and insoluble iron sulfate-polyphosphate type phase in preference to insoluble rare earth and thorium containing polyphosphates identified during acid baking of monazite alone. After baking at 650 °C, the iron sulfate-polyphosphate type phase was altered to a more soluble form, leading to an increase in dissolution of iron, phosphorus and thorium. Acid baking at 800 °C led to the formation of FePO4, Fe2O3, CePO4 (monazite) and in some cases CeO2, causing a decrease in leaching of rare earths and thorium, and either an increase or a decrease in leaching of iron and phosphorus depending on the formation of FePO4 versus Fe2O3
Hydrochar amendments stimulate soil nitrous oxide emission by increasing production of hydroxyl radicals and shifting nitrogen functional genes in the short term: A culture experiment
No full textThe application of waste biomass-derived hydrochar to soil may cause extremely intensive nitrous oxide (N2O) fluxes that can challenge our current mechanistic understanding of the global nitrogen cycle in the biosphere. In this study, two waste biomasses were used to prepare cyanobacterial biomas-derived hydrochar (CHC) and wheat straw-derived hydrochar (SHC) for short-term incubation experiments to identify their effects and mechanisms of waste biomass-derived hydrochar on soil N2O efflux, with time-series samples collected for N2O efflux and soil analysis. The results showed that CHC and SHC caused short-term bursts of N2O effluxes without nitrogen inputs. Moreover, the enrichment of exogenous organics and nutrients at the hydrochar-soil interface was identified as the key factor for enhancing N2O fluxes, which stimulated microbial nitrification (i.e., increased gene copy number of ammonia oxidizing bacteria) and denitrification (i.e., increased gene copy number of nitrate and N2O reducing bacteria) processes. The concentrations of Fe (II) and hydroxyl radicals (HO•) were 6.49 and 5.63 times higher, respectively, in the hydrochar layer of CHC than SHC amendment. Furthermore, structural equation models demonstrated that HO•, as well as soil microbiomes, played an important role in driving N2O fluxes. Together, our findings provide a deeper insight into the assessment and prognosis of the short-term environmental risk arising from agricultural waste management in integrated agriculture. Further studies under practical field application conditions are warranted to verify the findings
Long-acting injectable antipsychotic treatment during pregnancy: Outcomes for women at a tertiary maternity hospital
No full textOur study aimed to examine pregnancy, neonatal and psychosocial outcomes for women treated with LAIs at tertiary maternity hospital. A retrospective review of all women who were treated with LAIs between 1999 and 2017. Cases were identified via the hospital dispensary system and outcome data were extracted case notes as well as the midwifery notification system. Measures included sociodemographic data, smoking, alcohol and illicit substance use, pregnancy complications such as gestational diabetes, and neonatal outcomes. Psychosocial profiles such as psychiatric admission during pregnancy and statutory child protection involvement were also assessed. Where available, outcomes were compared with state population data. The study found 38 pregnancies to 36 women, who had LAI treatment. Two congenital malformations (5.7%) were recorded. Compared to general population data, pregnant women treated with LAIs were more likely to have obstetric complications including gestational diabetes and pregnancy hypertension and special care nursery admission for their babies. They also had elevated rates of psychiatric admissions during pregnancy and statutory child protection involvement. Outcomes were similar first and second generation LAIs exposure. As women on LAI have limited options for treatment of their psychotic disorders, the findings point towards a need for enhanced multidisciplinary pregnancy care for this vulnerable cohort