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Predictive modelling of MapReduce job performance in cloud environments using machine learning techniques
No full textWithin the Hadoop ecosystem, MapReduce stands as a cornerstone for managing, processing, and mining large-scale datasets. Yet, the absence of efficient solutions for precise estimation of job execution times poses a persistent challenge, impacting task allocation and distribution within Hadoop clusters. In this study, we present a comprehensive machine learning approach for predicting the execution time of MapReduce jobs, encompassing data collection, preprocessing, feature engineering, and model evaluation. Leveraging a rich dataset derived from comprehensive Hadoop MapReduce job traces, we explore the intricate relationship between cluster parameters and job performance. Through a comparative analysis of machine learning models, including linear regression, decision tree, random forest, and gradient-boosted regression trees, we identify the random forest model as the most effective, demonstrating superior predictive accuracy and robustness. Our findings underscore the critical role of features such as data size and resource allocation in determining job performance. With this work, we aim to enhance resource management efficiency and enable more effective utilisation of cloud-based Hadoop clusters for large-scale data processing tasks</p
Binder-free anodes for potassium-ion batteries comprising antimony nanoparticles on carbon nanotubes obtained using electrophoretic deposition
No full textAntimony has a high theoretical capacity and suitable alloying/dealloying potentials to make it a future anode for potassium-ion batteries (PIBs); however, substantial volumetric changes, severe pulverization, and active mass delamination from the Cu foil during potassiation/depotassiation need to be overcome. Herein, we present the use of electrophoretic deposition (EPD) to fabricate binder-free electrodes consisting of Sb nanoparticles (NPs) embedded in interconnected multiwalled carbon nanotubes (MWCNTs). The anode architecture allows volume changes to be accommodated and prevents Sb delamination within the binder?free electrodes. The Sb mass ratio of the Sb/CNT nanocomposites was varied, with the optimized Sb/CNT nanocomposite delivering a high reversible capacity of 341.30 mA h g−1 (∼90% of the initial charge capacity) after 300 cycles at C/5 and 185.69 mA h g−1 after 300 cycles at 1C. Postcycling investigations reveal that the stable performance is due to the unique Sb/CNT nanocomposite structure, which can be retained over extended cycling, protecting Sb NPs from volume changes and retaining the integrity of the electrode. Our findings not only suggest a facile fabrication method for high-performance alloy-based anodes in PIBs but also encourage the development of alloying-based anodes for next-generation PIBs.</p
Modulation of water vapor sorption by pore engineering in isostructural square lattice topology coordination networks
No full textWe report a crystal-engineering study conducted upon a platform of three mixed-linker square lattice (sql) coordination networks of general formula [Zn(Ria)(bphy)] [bphy = 1,2-bis(pyridin-4-yl)hydrazine, H2Ria = 5-position-substituted isophthalic acid, and R = −Br, −NO2, and −OH; compounds 1−3]. Analysis of single-crystal X-ray diffraction data of 1−2 and the simulated crystal structure of 3 revealed that 1−3 are isomorphous and sustained by bilayers of sql networks linked by hydrogen bonds. Although similar pore shapes and sizes exist in 1−3, distinct isotherm shapes (linear and S shape) and uptakes (2.4, 11.6, and 13.3 wt %, respectively) were observed. Ab initio calculations indicated that the distinct water sorption properties can be attributed to the R groups, which offer a range of hydrophilicity. Calculations indicated that the significantly lower experimental uptake in compound 1 can be attributed to a constricted channel. The calculated water-binding sites provide insights into how adsorbed water molecules bond to the pore walls, with the strongest interactions, water−hydroxyl hydrogen bonding, observed for 3. Overall, this study reveals how pore engineering can result in large variations in water sorption properties in an isomorphous family of rigid porous coordination networks.</p
Impact of organic anions on metal hydroxide oxygen evolution catalysts
No full textStructural metamorphosis of metal−organic frameworks (MOFs) eliciting highly active metal-hydroxide catalysts has come to the fore lately, with much promise. However, the role of organic ligands leaching into electrolytes during alkaline hydrolysis remains unclear. Here, we elucidate the influence of organic carboxylate anions on a family of Ni or NiFe-based hydroxide type catalysts during the oxygen evolution reaction. After excluding interfering variables, i.e., electrolyte purity, Ohmic loss, and electrolyte pH, the experimental results indicate that adding organic anions to the electrolyte profoundly impacts the redox potential of the Ni species versus with only a negligible effect on the oxygen evolution activities. In-depth studies demonstrate plausible reasons behind those observations and allude to far-reaching implications in controlling electrocatalysis in MOFs, mainly where compositional modularity entails fine-tuning organic anions</p
Tranexamic acid use in sarcoma surgery patients: A systematic review and meta‐analysis
No full textIntroduction: Perioperative bleeding increases morbidity and mortality in sarcoma patients. Tranexamic acid (TXA), an antifibrinolytic, is widely utilized in non‐sarcoma orthopaedic surgeries, but its adoption in sarcoma surgery is hindered by concerns about thrombotic events. Methods: Searches in Ovid MEDLINE, EMBASE, and CENTRAL were performed without date restrictions. Inclusion criteria encompassed sarcoma patients under-going surgery with TXA intervention. Two authors independently screened studies, resolved conflicts, and assessed biases. Results: Eight studies met inclusion criteria, comprising 2142 patients. TXA administration varied in dose and timing across studies. Meta‐analysis revealed significantly reduced mean blood loss with TXA of −462.5 mL ([95% confidence interval [CI: −596.7, −328.31], p < 0.001) but no difference in transfusion rates (odds ratio [OR] = 0.51 [95% CI: 0.14–1.89]) or venous thromboembolism events (OR = 0.93 [95% CI: 0.40, 2.16]). Study biases were predominantly moderate to high due to retrospective designs and lack of control for confounders. Quality of reporting varied, with limitations identified in outcome reporting and effect size estimation. Conclusions: Despite evidence of reduced blood loss, the absence of prospective studies limits conclusive recommendations on TXA use in sarcoma surgery. Further research is warranted to determine optimal TXA regimens and assess safety concerns regarding thrombotic events in this patient population.</p
Effective supports for women computer science academics: practice-based insights in an Irish context
No full textThis paper focuses on the under-representation of women computer science faculty and describes an intervention programme called Athena SWAN which has been recently embraced by many Irish third level institutions as part of their efforts to promote gender equity. It details four practice-based initiatives that have been recently implemented within the University of Limerick as part of this programme that have proven effective, outlining the processes undertaken and their practical outcomes. In doing so, it highlights the importance of this intervention process but also draws attention to the need for wider cultural change in supporting gender equity and removing the workplace barriers that impede advancement and retention of women computer science faculty.</p
People, places, things and communities: expanding behaviour settings theory in the twenty-first century
No full textTrends and developments in recent behavioural and cognitive sciences demonstrate the need for a well-developed theoretical and empirical framework for examining the ecology of human behaviour. The increasing recognition of the role of the environment and interaction with the environment in the organization of behaviour within the cognitive sciences has not been met with an equally disciplined and systematic account of that environment (Heft 2018 Ecol. Psychol. 30, 99–123 (doi:10.1080/10407413.2018.1410045); McGann 2014 Synth. Philos. 29, 217– 233). Several bodies of work in behavioural ecology, anthropology and ecological psychology provide some frameworks for such an account. At present, however, the most systematic and theoretically disciplined account of the human behavioural ecosystem is that of behaviour settings, as developed by the researchers of the Midwest Psychological Field Station (see Barker 1968 Ecological psychology: concepts and methods for studying the environment of human behavior). The articles in this theme issue provide a critical examination of these theoretical and methodological resources. The collection addresses their theoretical value in connecting with contemporary issues in cognitive science and research practice in psychology, as well as the importance of the methodological specifics of behaviour settings research. Additionally, articles diagnose limitations and identify points of potential extension of both theory and methods, particularly with regard to changes owing to the advance of technology, and the complex relationship between the individual and the collective in behaviour settings work. This article is part of the theme issue ‘People, places, things, and communities: expanding behaviour settings theory in the twenty-first century’.</p
Feasibility and advantages of continuous synthesis of bioinspired silica using CO2 as an acidifying agent
No full textIn this work, we present a method for the continuous synthesis of bioinspired porous silica (BIS) particles using carbon dioxide (CO2) as an acidifying agent. Typical BIS synthesis uses strong mineral acids (e.g., HCl) to initiate the hydrolysis and subsequent condensation reactions. The use of strong acids leads to challenges in controlling the reaction pH. The synthesis approach proposed in this work offers for the first time CO2 as an attractive alternative for the synthesis of BIS and demonstrates the continuous process. The developed method leverages the mild acidic and the self-buffering nature of the CO2 combined with additional options for controlling mass transfer rates to facilitate enhanced control of pH, which is crucial for controlling the properties of synthesized BIS. Proof of concept experiments conducted in continuous mode demonstrated a yield of over 70% and a surface area exceeding 500 m2 /g. These results indicate the successful synthesis of BIS using CO2 with properties in the desired range. The enhanced pH control offered by this CO2-based process will facilitate the implementation of a sustainable and robust continuous process for BIS synthesis.</p
Effects of a telehealth-delivered mediterranean diet intervention in adults with rheumatoid arthritis (MEDRA): a randomised controlled trial
No full textObjective To compare the effects a Mediterranean diet (MedDiet) versus the Irish Healthy Eating Guidelines (HEG) on physical function and quality of life in adults with rheumatoid arthritis (RA) in Ireland. Methods Forty-four adults with RA were randomised (1:1) to the MedDiet or HEG for 12 weeks. The intervention included three video teleconsultations and two follow-up telephone calls facilitated by a Registered Dietitian (RD). Changes in physical function by Health Assessment Questionnaire- Disability Index (HAQ-DI) and quality of life by Rheumatoid Arthritis Quality of Life Questionnaire (RAQoL) were the primary outcomes measured. Secondary outcomes included changes in dietary adherence, physical activity by Yale Physical Activity survey (YPAS), patient perceived pain and general health, and anthropometric measures. All measurements were administered at baseline and repeated at 6 and 12 weeks. Results Forty participants completed the study. Participants were primarily females (87.5%), mean age was 47.5±10.9 years. At the end of the intervention, participants in the MedDiet group reported significantly better physical function (p=0.006) and quality of life (p=0.037) compared to HEG group. From baseline to 12 weeks, physical function significantly improved in both diet groups, MedDiet (0.9±0.5 to 0.5±0.4 units, p<0.001) and HEG (1.4±0.7 to 1.0±0.6 units, p<0.001). Quality of life also significantly improved in the MedDiet (10.1±7.5 to 4.0±4.7 units, p<0.001) and HEG group (11.25±7.2 to 7.9±6.4 units, p=0.048). Physical activity improved significantly in the MedDiet (56.7±28.6 to 70.6±33.5 points, p=0.01) but not within the HEG group despite similar recommendations. Conclusion Adhering to the MedDiet and Irish Healthy Eating Guidelines resulted in improvements in RA patient reported outcomes. The changes observed in both diet groups are likely due to the improvement in overall diet quality irrespective of dietary prescription</p
On the role of excipients in biopharmaceuticals manufacture: Modelling-guided formulation identifies the protective effect of arginine hydrochloride excipient on spray-dried Olipudase alfa recombinant protein
No full textBiopharmaceuticals are labile biomolecules that must be safeguarded to ensure the safety, quality, and efficacy of the product. Batch freeze-drying is an established means of manufacturing solid biopharmaceuticals but alternative technologies such as spray-drying may be more suitable for continuous manufacturing of inhalable bio-pharmaceuticals. Here we assessed the feasibility of spray-drying Olipudase alfa, a novel parenteral therapeutic enzyme, by evaluating some of its critical quality attributes (CQAs) in a range of excipients, namely, trehalose, arginine (Arg), and arginine hydrochloride (Arg-HCl) in the sucrose/methionine base formulation. The Arg-HCl excipient produced the best gain in CQAs of spray-dried Olipudase with a 63% reduction in reconstitution time and 83% reduction in the optical density of the solution. Molecular dynamics simulations revealed the atomic-scale mechanism of the protein–excipient interactions, substantiating the experimental results. The Arg-HCl effect was explained by the calculated thermal stability and structural order of the protein wherein Arg-HCl acted as a crowding agent to suppress protein aggregation and promote stabilization of Olipudase post-spray-drying. Therefore, by rational selection of appropriate excipients, our experimental and modelling dataset confirms spray-drying is a promising technology for the manufacture of Olipudase and demonstrates the potential to accelerate development of continuous manufacturing of parenteral biopharmaceuticals.</p