151398 research outputs found
Sort by
The roles of switching and inhibition in adult counterintuitive scientific thinking
No full textLearning science often appears to involve replacement of naïve, intuitive ideas with correct, counterintuitive ones. Recent studies indicate that the old naïve, intuitive ideas are not actually replaced but exist alongside the correct but often counterintuitive ones. On this account, newer knowledge for scientific thinking might involve inhibition of the old idea. However, instead of merely inhibiting old ideas, it is possible that switching is necessary to select between new and old scientific ideas. In this study, we explored the direct and indirect contributions of behavioural inhibition, cognitive inhibition and switching to intuitive and counterintuitive science reasoning in adults (N = 167). After replicating the commonly observed processing costs of counterintuitive items relative to intuitive ones, we find that individual differences in switching rather than in inhibition are most strongly associated with variation in the accuracy and speed of adult intuitive and counterintuitive science reasoning. These results suggest that adults switch between older and newer ideas when reasoning about science rather than suppressing one in favour of the other
Formulation and evaluation of hydrogel-forming microarray patches for transdermal primaquine and chloroquine delivery in malaria therapy
No full textMalaria is still major concern in global health. The standard treatment for malaria involves a combination of chloroquine (CQ), which targets blood-stage parasites, and primaquine (PQ), which eliminates hepatic hypnozoites to prevent relapses. However, these drugs present limitations, including poor adherence due to frequent oral dosing and gastrointestinal side effects. To address these challenges, this study successfully developed, optimised, and characterised lyophilised reservoirs loaded with PQ and CQ, which were incorporated into hydrogel-forming microarray patches (MAPs) for improved malaria treatment. Using a Design of Experiments (DoE) approach, the optimised lyophilised reservoirs dissolved rapidly, within 7 s for CQ and 16 s for PQ. In vitro permeation studies using dermatomed neonatal porcine skin demonstrated efficient drug delivery of approximately 40 mg (70 % delivery efficiency) of each drug over 24 h. Pharmacokinetic analysis in rats showed that MAP administration significantly increased Cmax values from 0.68 ng/mL to 1.68 ng/mL for CQ, and from 14.32 ng/mL to 47.20 ng/mL for PQ compared to oral delivery. Moreover, the area under the curve (AUC0-72h) for the MAP group was 4.4-fold higher for CQ and 1.3-fold higher for PQ compared to oral administration. Efficacy studies in a murine malaria model demonstrated that MAP-delivered PQ and CQ reduced parasitaemia by 99.8 % in treated animals. These findings highlight the potential of MAP technology as a minimally-invasive, sustained drug delivery platform for malaria treatment, potentially offering improved patient adherence, reduced hepatoxicity, and enhanced therapeutic outcomes.<br/
Formulation and evaluation of hydrogel-forming microarray patches for transdermal primaquine and chloroquine delivery in malaria therapy
No full textMalaria is still major concern in global health. The standard treatment for malaria involves a combination of chloroquine (CQ), which targets blood-stage parasites, and primaquine (PQ), which eliminates hepatic hypnozoites to prevent relapses. However, these drugs present limitations, including poor adherence due to frequent oral dosing and gastrointestinal side effects. To address these challenges, this study successfully developed, optimised, and characterised lyophilised reservoirs loaded with PQ and CQ, which were incorporated into hydrogel-forming microarray patches (MAPs) for improved malaria treatment. Using a Design of Experiments (DoE) approach, the optimised lyophilised reservoirs dissolved rapidly, within 7 s for CQ and 16 s for PQ. In vitro permeation studies using dermatomed neonatal porcine skin demonstrated efficient drug delivery of approximately 40 mg (70 % delivery efficiency) of each drug over 24 h. Pharmacokinetic analysis in rats showed that MAP administration significantly increased Cmax values from 0.68 ng/mL to 1.68 ng/mL for CQ, and from 14.32 ng/mL to 47.20 ng/mL for PQ compared to oral delivery. Moreover, the area under the curve (AUC0-72h) for the MAP group was 4.4-fold higher for CQ and 1.3-fold higher for PQ compared to oral administration. Efficacy studies in a murine malaria model demonstrated that MAP-delivered PQ and CQ reduced parasitaemia by 99.8 % in treated animals. These findings highlight the potential of MAP technology as a minimally-invasive, sustained drug delivery platform for malaria treatment, potentially offering improved patient adherence, reduced hepatoxicity, and enhanced therapeutic outcomes.<br/
The warification of international humanitarian law and the artifice of artificial intelligence in decision-support systems: restoring balance through the legitimacy of military operations
No full textWe are observing a worrying rise in civilian harm in armed conflict and at the same time an increasing autonomy in warfare. Both phenomena are happening against the backdrop of 75 years of the Geneva Conventions and the upcoming 50th anniversary of their Additional Protocols. In this context, IHL with its hallmark of balancing the principles of humanity and military necessity is facing unprecedented pressure. Over the past three decades, the narrative has shifted toward so-called "clean" warfare through more precise munitions and methods. However, this period has also seen an unprecedented number of civilian harm incidents, largely due to an increasingly broad interpretation of legal targeting permissions-a phenomenon we call the warification of IHL. The convergence of warification and increasing battlefield autonomy has come into sharp focus in the ongoing conflict between Israel and Hamas. Reports indicate that the IDF has used AI-enabled decision-support systems (AI-DSS), including "Lavender," "The Gospel," and "Where's Daddy," to help generate and process targeting lists. These systems have played a role in the high civilian casualty numbers seen in this conflict, reaching multiple tens of thousands. In this chapter, we argue that certain use of AI-DSS may risk exacerbating this warification and propose a path forward with the legitimacy of military operations at its core. We emphasise transparency, accountability, compliance with the rule of law (both its letter and spirit) and civilian harm mitigation as key elements of legitimacy. These elements guide the shift away from warification and toward restoring IHL's delicate balance
Geometrical quality prediction of machining process by Exechon X-mini PKM through deformation modelling and error compensation
No full textParallel Kinematic Machines (PKMs) offer enhanced motion dynamics and flexibility, bridging the gap between conventional CNC machines and industrial robots. Stiffness, a key determinant of machining accuracy, is often modelled with limited consideration of gravitational effects, leading to reduced predictive accuracy. This paper introduces a novel stiffness modelling approach that integrates a theoretical model without gravity and gravity-based parameter optimisation through experimental analysis. Comprehensive stiffness measurements were conducted to isolate gravitational effects on the machine structure, enabling precise calibration of the theoretical model for accurate stiffness prediction. A six-dimensional stiffness analysis of the X-Mini machine tool using the optimised model demonstrated improved prediction accuracy, reducing errors by 14 %, 21 %, and 8 % in the X, Y and Z directions, respectively. Predicted stiffness and estimated cutting forces were used to compute workspace deformations, which were then compensated by modifying the depth of cut in slot milling. Experimental validation demonstrated the method’s effectiveness, achieving a machined shape error prediction accuracy of 6–9 µm. This approach can be well applied to shape quality prediction of machined parts by robots and machine tools.<br/
Tensile behaviour of basalt textile-reinforced mortar (TRM) composites at intermediate strain rates for structural strengthening
No full textTextile-reinforced mortar (TRM) composites have become a preferred solution for strengthening masonry and concrete structures owing to their durability, ease of application, and compatibility. The quasi-static tensile response of TRMs is well established; however, their performance under dynamic loading remains poorly understood. This study investigates the tensile behaviour of BTRM composites at strain rates ranging from 10−5 to 9/s, using high-speed servo-hydraulic and Zwick testing systems and the digital image correlation (DIC) technique. Two specimen preparation methods were explored: moulded (M) and cut (C). The BTRM composites demonstrated strain-hardening behaviour, displaying bi-linear or tri-linear stress-strain responses depending on the strain rate and specimen type. C specimens maintained relatively consistent mechanical properties across the strain rates, while M specimens experienced enhanced first cracking stress, tensile strength, strain capacity, and toughness beyond 5/s. The post-cracking stiffness and efficiency of the reinforcing grid were reduced with increasing strain rate, with efficiency factors dropping from >0.9 in quasi-static tests to as low as 0.5 under dynamic loading. The common failure mechanisms were multiple cracking, grid rupture and telescopic failures. Extensive grid pullout and delamination failures were observed only under dynamic loading conditions. Compared to glass and carbon TRM composites, BTRMs at dynamic strain rates showed similar stress-strain relationships but lower strength and strain capacity. The results reveal the potential and constraints of BTRMs in dynamic structural applications, pointing to the need for stronger grid-to-mortar interactions to improve performance at dynamic strain rates.<br/
Quantification of antibiotic diffusion in biofilms using gold nanostar surface‐enhanced Raman spectroscopy
No full textThe increased resistance to antibiotics shown by bacteria in biofilms is believed to be partly the result of the limited penetration of antibiotics. However, there are no well-established techniques which allow quantitative, label-free monitoring of antibiotic transport in biofilms. Here, it is shown that surface-enhanced Raman spectroscopy (SERS) with gold nanostars (NS) can be used for the detection of levofloxacin (Levo) in Staphylococcus aureus biofilms at clinically relevant concentrations. Ex situ studies showed that although matrix interference reduced the sensitivity compared to aqueous solutions, quantitative detection remained possible. With intact biofilms, monitoring the SERS signals from layers of NS embedded at specific depths allowed the time-dependence of the penetration of Levo from the surface to the embedded layer to be measured and the diffusion coefficient of Levo to be calculated. The measured value of D = 2.79 ± 0.79 × 10−9 cm2 s−1 is over three orders of magnitude lower than in aqueous solutions. This work is the first demonstration that SERS can be a powerful method for investigating antibiotic transport in biofilms, offering new insights into resistance mechanisms and supporting the development of more effective antimicrobial strategies.<br/
Accurate internal methane dry reforming kinetic models for solid oxide fuel cells
No full textCoupling with solid oxide fuel cells, methane dry reforming is a promising pathway for energy production from two greenhouse gases. However, the influence of carbon dioxide and electrochemical reactions on the internal dry reforming reaction within the fuel cells remains debatable, requiring accurate kinetic models to describe the internal reforming behaviors. In this study, we investigated the Power-Law and Langmuir Hinshelwood–Hougen Watson models in an electrolyte-supported solid oxide fuel cell with a NiO-GDC-YSZ anode to get accurate models for internal dry methane reforming. The current density used in this study ranges from 0 to 1000 A/m2 at 973 K to 1173 K to estimate various kinetic parameters. The influence of the electrochemical reactions on the adsorption terms, the equilibrium of the reactions, the activation energy, the pre-exponential factor of the rate constant, and the adsorption equilibrium constant were studied. Furthermore, the adsorption enthalpy and entropy were investigated for the first time to understand the Gibbs free energy of CO2 adsorption. The accuracy of kinetic models for estimating kinetic parameters was also evaluated. The dual-site models show better estimations than the other models and are then utilized to predict the reaction rate in the fuel cell. The derived kinetic parameters were consistent with values reported in the literature, confirming the reliability and general applicability of the developed models. For the first time, the adsorption enthalpy, entropy, and Gibbs free energy of CO2 adsorption were quantified in a DRM–SOFC system, providing new thermodynamic insight into electrochemically influenced adsorption behavior. However, the dual-site LHHW models’ accuracy was still insufficient, indicating a need for further research to develop a comprehensive kinetic model for internal dry reforming in fuel cells. This study provides essential parameters for future simulations and highlights the need for a more detailed examination of reforming kinetic models.<br/
