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Effect of comminution mechanism on flotation of coarse composites
No full textThis study investigates the impact of comminution mechanisms of GRolls® and rod mills on particle characteristics and flotation performance. Particular focus is given to coarse particles flotation, aiming at energy reduction in the grinding circuit. Experiments were carried out using both HydroFloat™ and mechanically agitated cells using porphyry copper–gold ore. GRolls® demonstrated superior coarse particle flotation due top referential breakage along mineral boundaries, producing better-liberated particles with higher Cu exposure. In the HydroFloat™,GRolls® products achieved a Cu grade of 3.6 % in the + 150 μm fraction, compared to 2.8 %for rod mill products. In mechanically agitated cells, GRolls® products also delivered superior performance inthe + 150 μm fraction, with a Cu recovery of 60 % and grade of 5.8 %, while rod mill products achieved 52 %recovery and 3.9 % grade.
Particle morphology also influenced the flotation performance, with elongated particles correlating with higher grades in coarser fractions and rounded particles linked to increased gangue entrainment in finer fractions. Fluidized bed properties in the HydroFloat™ were similar for both comminution methods, indicating that when particle size distributions are closely matched and relatively coarse particles are used at low superficial water velocities, particle morphology has minimal impact on bed dynamics. These findings highlight the importance of comminution strategies and particle shape in optimizing flotation performance for energy-efficient ore processing
Injectable or non-injectable GnRH analogues for control of swine reproduction. A systematic review and meta-analysis
No full textGonadotropin-releasing hormone (GnRH) analogues are widely applied in swine production to synchronise ovulation and so facilitate fixed-time artificial insemination (FTAI). Both injectable and non-injectable formulations are available; however, their comparative effects on reproductive performance remain unclear. This systematic review and meta-analysis, conducted in accordance with PRISMA guidelines, evaluated the impact of GnRH analogues on conception rate (CR), farrowing rate (FR), weaning-to-estrus interval (WEI), piglets born per litter (PBL), and piglets born alive (PBAL). Random-effect models were used to estimate pooled mean differences (MDs) with 95 % confidence intervals (CIs). Heterogeneity was assessed using the I² statistic, and subgroup analyses compared injectable versus non-injectable regimens. The effect of a subgroup was analysed by administration route, insemination protocol, frequency, or AI method. Across the 27 included studies, GnRH analogue administration did not improve CR (MD = –0.00, 95 % CI: –0.05 to 0.05) or FR (MD = –0.02, 95 % CI: –0.06 to 0.01). Subgroup analyses showed no significant differences between injectable and non-injectable routes for any outcome, and heterogeneity remained low (I² = 0 %). A modest reduction in total PBL (MD = –0.33, 95 % CI –0.57 to –0.08) was evident without effect of subgroup. Although PBAL were slightly reduced (MD = –0.52, 95 % CI –0.82 to –0.22), particularly in subgroups by insemination protocol and insemination frequency there is no biological explanation for this finding. These findings suggest that while GnRH analogues are effective for synchronising ovulation, their influence on litter size is biologically modest. Importantly, noninjectable formulations demonstrated comparable outcomes to injectable approaches, supporting their potential as practical, less-invasive alternatives in commercial settings. To enable robust and parity-specific recommendations, further research should comprise adequately powered, parity-stratified randomised trials in gilts and primiparous (P1) sows. The effects of conventional and post-cervical routes on single FTAI should be assessed. Administration of standardised GnRH analogue dose and timing should be carried out to verify ovulation, control sperm numbers, and pre-specify outcomes (CR, FR, WEI, PBL, and PBAL).Ahm Musleh Uddin, Gebremeskel Mamu Werid, Thien D. Van, Yunmei Song, Sanjay Garg, Roy N. Kirkwood, Kiro R. Petrovsk
Functionally graded concrete: a comprehensive review of design concepts, production methods, material innovations, and structural performance
No full textFunctionally graded concrete (FGC) structures have garnered significant attention in research and industry communities, accompanying with growing emphasis on low-carbon and rapid advancement of concrete 3D printing. The inherent design flexibility of FGC enables the integration of diverse concrete types, resulting in superior performance in durability, cost-effectiveness, and sustainability. Moreover, this flexibility allows FGC to address project-specific requirements, fostering the intelligent and customized development of construction projects. This paper presents two principal forms of FGC structures: material-functionally graded (varying composition or additives) and structural-functionally graded (varying geometry) concrete structures. Recent progress, challenges in the design, fabrication processes, performance optimization, and application of FGC are reviewed further. Compared to conventional casting, 3D printing deposition achieves precise spatial control of material distribution and geometry, enabling performance-optimized FGC fabrication. Nevertheless, the inherent anisotropy of 3D-printed concrete induces interlayer stress concentration, leading to pronounced interfacial delamination. Consequently, interlayer optimization constitutes a pivotal research frontier for 3D-printed FGC systems. Furthermore, although FGC enhances structural performance, its material heterogeneity necessitates advanced prediction methodologies—an urgent research priority to resolve property uncertainty
Linking mill shell vibration to particle size reduction gradient along a high-intensity grinding mill chamber
No full textA high-intensity grinding (HIG) mill is an energy-efficient machine designed for fine and ultra-fine grinding of hard materials. Real-time particle size monitoring in a HIG mill is crucial for optimising grinding efficiency, controlling product fineness, reducing energy consumption, and preventing over-grinding or under-grinding, which can impact downstream processes. While direct inline and online measurement is commercially available through dedicated caliper, laser, or ultrasound based systems installed downstream of the mill, the measurement location does not provide insights of particle size reduction profile along the grinding chamber. Monitoring particle size reduction through cascaded grinding stages (sub-chambers) along the entire tall narrow mill chamber can help detect and rectify abnormalities in grinding dynamics at an early stage, which however, is not well studied. Motivated by the advantages of vibration based monitoring techniques featuring minimal bespoke modification to an existing plant, this study provides a preliminary investigation on the hypothesis of inferring particle size via mill shell vibrations, with a view on the viability, complexity, and worthiness. Vibrations were measured at different positions axially along the external wall of the grinding chamber of a Metso HIGmill™ pilot plant running with different groups of grinding media while maintaining other process variables constant. The hypothesis is theoretically discussed along with experiment results. Complex vibration phenomena arising from the interplay of grinding media, energy transfer, and slurry rheology partially support the hypothesis and also suggest that accurate estimation necessitates complicated modelling and extensive calibration. The added complexity requires careful consideration of trade-offs against the potential benefits
Realistic particle shape representation using clump in DEM: A critical state soil mechanics study
No full textLink to a related website: https://orcid.org/0000-0002-9726-0241, ORCID profile - Le, Tri TRecent advances in discrete element modelling (DEM), aided by X-ray micro-computed tomography, enable realistic particle shape reconstruction using clumped spheres. While an increasing number of elemental spheres per clump (N-ele) enhances shape fidelity, it significantly raises computational cost due to the increase in number of total spheres involved in each step of computation. At present, no clear consensus exists on how to optimise clump reconstruction for realistic shapes in DEM to balance efficiency and predictive accuracy. This study addresses the computational challenges arising from numerically representing complex particle geometries. Results show that key shape descriptors and macro and micro mechanical behaviours of a realistic sand particle can be effectively captured with N(ele )of 25, avoiding the need for excessive values. More importantly, under critical state theory, triaxial simulations revealed that deviations in elongation index (<6.48 %), flatness index (<4.74 %), volume (<9%), and sphericity (<6.40 %) were sufficient to reproduce critical state lines, stress ratios, and behavioural correlations involving the initial state parameter. At the micro scale, the framework of bimodal stress transmission demonstrated that increased N(ele )mainly affected the weak contact force subnetwork, i.e., fabric anisotropy. In contrast, the strong contact force subnetwork, dominant in stress transmission, remained unaffected. These findings support efficient DEM modelling of realistic particles without requiring excessive shape detail, thereby reducing computational resource demands and facilitating large-scale studies and practical applications
Management of medical device alarms in intensive care units: A scoping review
No full textAvailable online 14 January 2026BACKGROUND: The presence of medical device alarms in the intensive care unit (ICU) has increased significantly over the past decade due to technological advancements. A troubling paradox is that while alarms are designed to keep patients safe, the overabundance of noise and frequency of nonactionable alarms is associated with alarm fatigue in nurses. OBJECTIVE: The objectives of this study were to explore and describe the interventions and recommendations for alarm management of medical devices in the ICU environment. METHODS: This scoping review was conducted using the Joanna Briggs Institute framework and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. DATA SOURCES: Data sources included APA PsycINFO (Ovid), EBSCO CINAHL, Elsevier Embase, Emcare (Ovid), Epistemonikos, MEDLINE (Ovid), PROSPERO, Elsevier Scopus (Ovid), and Clarivate Analytics Web of Science Core Collection from 1st January 2014 to 31st December 2024 and supplemented with hand searching of references from included studies. RESULTS: A total of 44 studies met the inclusion criteria: 28 were quantitative, 12 were qualitative, and four were mixed-method studies. The most common intervention utilised for the management of medical device alarms was clinical education followed by alarm customisation. A total of 150 recommendations to manage medical device alarms were made that were themed into a collaborative framework to guide improvements. CONCLUSIONS: There is no single or easy intervention that will address the management of clinical alarms in the ICU. There is a strong need for shared responsibility across the critical care faculty that requires effective collaboration, ongoing involvement, and vigilance across whole multidisciplinary ICU team.Vivienne Leigh, Carol Grech, Allison Roderick, Michelle A. Kelly, Lemuel Pelentso
Design, delivery, implementation, and evaluation of simulated clinical placements: a scoping review and evidence and gap map of the current state of evidence
No full textOnlinePublBackground Clinical placements allow health professions students to apply theoretical knowledge in clinical settings. For various economical, practical, and preferential reasons, some programs and institutions have trialled and established simulated clinical placements. This scoping review examines the evidence on the design, delivery, implementation, and evaluation of simulated clinical placements. Methods We conducted a scoping review using JBI methods and reported according to the PRISMA-ScR. PubMed (NCBI), Embase (Embase.com), and CINAHL (EBSCO), PsycINFO (EBSCO) were searched. Reviewers screened title and abstracts and full-texts articles to assess for eligibility. Data were extracted and analysed with descriptive statistics and qualitative content analysis. Evidence and gap maps were developed to visualise the analysed data. Results There were 131 documents included in this scoping review. Nursing (n = 77; 58.8%), physiotherapy (n = 10; 7.6%), and radiography (n = 9; 7.6%) were the most common fields where simulated clinical placements were trialled and established. Most studies originated the USA (n = 58; 44.3%), followed by Australia (n = 22; 16%), and the UK (n = 15; 11.5%). SCPs were experienced in-person (n = 57), or online (n = 46), with 18 documents reporting both in-person and online options. The percentage of replaced traditional clinical placement time most often ranged from between 0 and 50%, with seven documents reporting a replacement of between 76 and 100%. Several theoretical and conceptual frameworks were identified as being foundational in the establishment of simulated clinical placements. Learning outcomes, student outcomes, assessment types, regulatory and accreditation determinations and guidelines, resources (capital, human, technological, and student), costs and strengths, barriers, limitations and facilitators attributed to simulated clinical placements were identified. Conclusion Simulated clinical placements are increasingly established to capitalise on the opportunities and affordances they offer to health professions students, particularly when traditional placements become less feasible. Given the acceleration of placements that are being undertaken in simulated rather than traditional health care services, it is likely they will continue to be established well into the future. There are significant opportunities to shape learner experiences and performance through how we use simulation techniques in simulated clinical placements for the purpose of building student readiness for practice as health professionals.Danielle Pollock, Charles Marley, Grace Holland, Sabira Hasanoff, Matthew Tieu, Adam Montagu, Jenniffer Paguio, Raju Kanakula, Carrie Price, Zachary Munn, Ellen Davie
Can foreign aid mitigate the effects of climate variability in agriculture? Evidence from the low-and middle-income countries
No full textThis paper examines the effectiveness of foreign aid in the agricultural sector in the presence of climate variability. Climate variability, measured by fluctuations in temperature and precipitation rates, can disrupt production and, in particular, lower agricultural productivity and access to food. On the other hand, foreign aid in agriculture is targeted towards low- and middle-income countries to increase people's welfare and strengthen governments' development goals. Using data from 53 countries during 1990–2019, this study examines the effect of different types of agricultural aid on agricultural labour productivity in the presence of climate change shocks. In particular, four distinct channels of agricultural aid are considered, viz. Education, R&D, Policy, and Services. We find that R&D aid is the most effective channel in mitigating the adverse effects of climate variability. These results are robust to endogeneity biases and alternative estimation techniques. Findings from this study have substantial policy implications, as we show that aid effectively mitigates the impacts of climate change and presents sustainable growth opportunities for poor and developing countries.Rajabrata Banerjee, Vandana Arya, Saikat Sinha Ro
The microbiome: a determinant of reproductive health and fitness?
No full textOnlinePublThere is growing appreciation of the importance played by the reproductive tract microbiome in shaping fertility and reproductive health. Historically viewed as a microbially simple niche, the lower female reproductive tract is now recognised to harbour dynamic microbial communities that interact with host physiology to influence fertility, pregnancy outcomes, and reproductive disorders. Increasing evidence also implicates the comparatively low biomass microbiomes of the upper female reproductive tract and the male reproductive tract in reproductive health. This Views and Reviews special edition is made up of four articles that critically examine the ecological drivers of vaginal microbiota composition, the strengths and limitations of current microbiome assessment tools in fertility care, links between dysbiosis and female reproductive disorders, and emerging evidence implicating the male reproductive microbiome in sperm function and fertility. Collectively, these contributions highlight both the promise and the current limitations of microbiome-informed reproductive care, underscoring the need for rigorous, standardised, and outcome-focused research to support clinical implementation.David A. MacIntyre, Robert J. Norma
Real-time estimation of states and unknown boundary conditions in pressurized pipeline systems
No full textAccurate estimation of boundary conditions in pressurized pipelines is essential for effective monitoring, control, and fault detection. However, boundary variables such as unmeasured demands and unknown pressure heads are often unavailable, introducing uncertainty into hydraulic models. This study presents a real-time observer-based framework for joint estimation of system states and unknown boundary inputs. The approach employs the Elastic Water Column Model (EWCM) to derive a linear time-invariant (LTI) representation compatible with observer design. Because the system does not satisfy the observer matching condition, auxiliary outputs are generated to transform it into a matched form. These outputs are first estimated using a High-Gain Observer (HGO) and then incorporated into a Sliding Mode Observer (SMO) for reconstructing both states and boundary conditions. The framework is validated through two numerical case studies and laboratory experiments involving transient pipeline flows. Results demonstrate accurate real-time estimation of unknown boundary conditions using only internal pressure data. Compared with batch-based methods such as Expectation–Maximization and Weighted Least Squares, the proposed observer-based strategy provides a computationally efficient and real-time alternative for hydraulic system monitoring.Morteza Imani, Aaron Zecchin, Wei Zeng, Martin F. Lamber