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Prevalence and distribution of Plasmodium falciparum multidrug resistant 1 D1246Y allele among children in Ibadan Southwest, Nigeria
Get PDFThe emergence and spread of the Plasmodium falciparum multidrug-resistant 1 (Pfmdr1) allele pose a significant setback to global efforts to control and eradicate malaria infection by diminishing the efficacy of commonly prescribed antimalarial drugs, particularly in Sub-Saharan Africa, where malaria remains endemic. The Pfmdr1 D1246Y mutation is of specific importance due to its potential role in modulating parasite susceptibility to antimalarial medicines and treatment outcomes. This study aimed to determine the presence and prevalence of the wild-type and mutant D1246Y alleles of Pfmdr1 among children in Ibadan, Southwest Nigeria. A total of 133 archived DNA samples collected between March 2016 and June 2021 from children aged 6 to 132 months with varying malaria phenotypes (asymptomatic infection, uncomplicated, and severe malaria) were analyzed. The Pfmdr1 D1246Y allele was amplified via nested PCR, and the mutation was detected using the restriction enzyme EcoRV. The digested nested PCR products were resolved on a 2% agarose gel and visualized under ultraviolet light. All statistical analyses were performed using SPSS version 25, and statistical significance was set at p ≤ 0.05. Among the 133 samples, 97 (72.9%) were successfully genotyped. Of these, 50 (51.55%) carried the wild-type allele, while 47 (48.45%) had the mutant allele. Notably, the Pfmdr1-1246Y mutation was detected in all severe malaria cases (41/41, 100%), whereas its prevalence was significantly lower in asymptomatic (3/36, 8.3%) and uncomplicated malaria cases (3/20, 15%). The difference in mutation prevalence across the malaria phenotypes was statistically significant (p < 0.05). The study provided valuable insight into the coexistence of wild-type and mutant Pfmdr1 D1246Y alleles within the population. It revealed a significantly higher mutation rate in all severe malaria cases, while the wild-type allele remained more prevalent overall. These findings contribute to a deeper understanding of the possible role of the wild-type and mutant D1246Y alleles in the various clinical manifestations of malaria
Perturbative gravitational wave predictions for the real-scalar extended Standard Model
Get PDFWe perform a state-of-the-art study of the cosmological phase transitions of the real-scalar extended Standard Model. We carry out a broad scan of the parameter space of this model at next-to-next-to-leading order in powers of couplings. We use effective field theory to account for the necessary higher-order resummations, and to construct consistent real and gauge-invariant gravitational wave predictions. Our results provide a comprehensive account of the convergence of perturbative predictions for the gravitational wave signals in this model. For the majority of the parameter points in our study, we observe apparent convergence. While leading and next-to-leading order predictions of the gravitational wave amplitude typically suffer from relative errors between 10 and 104, at next-to-next-to-leading order the typical relative errors are reduced to between 0.5 and 50. Nevertheless, for those parameter points predicting the largest signals, potentially observable by future gravitational wave observatories, the validity of the perturbative expansion is in doubt
Enhancing Positional Accuracy of Mechanically Modified Industrial Robots Using Laser Trackers
Get PDFHighly accurate positioning of industrial robots is crucial to performing industrial operations with high quality. This paper presents a mechanical modification to an industrial robot aiming at enhancing the system actuation resolution, thereby enhancing its positional accuracy. The industrial robot under consideration is a six-degrees of freedom (DoF) robot with revolute joints. By integrating a linear stage, a prismatic joint is introduced to the robot’s end effector, reconfiguring it into a 7 DoF system with more precise step size capabilities. To improve the positional accuracy of the overall system, a closed-loop control structure is chosen. Positional feedback is provided using an industrial laser tracker. Initially, a multi-layer perceptron neural network (MLPNN) is used to identify the forward kinematics (FK) of the overall 6RP robotic system. The FK of the industrial robot using the pretrained MLPNN is then used online to compute the real-time sensitivity of positional error to changes in the joint angle values of the industrial robot and displacements of the prismatic joint. Different trajectories are used to test the accuracy of the proposed positioning algorithm. From the implementation results obtained using the proposed control structure, it is observed that the accuracy of the industrial robot improves significantly. Statistical results for five different points selected from the ISO 9283 trajectory over 30 times of measurements show an 82% improvement for the measurements using the proposed approach as compared to the original industrial robot controller
Standing Among the Spartans: Institutions and Status within the Spartiate Community
No full textConformity, uniformity, institutionality, exceptionality – each of these terms encapsulates an aspect of the common perception of Sparta, both among scholars and in the popular imagination.This volume seeks to interrogate how rightly we may apply these terms to the Spartan citizen community in the classical period (approximately 500-350 BC) and reveals a much greater level of differentiation within this social group than is often assumed.Drawing upon recent scholarship on Sparta, theoretical and methodological discussions from within the wider fields of classical studies and ancient history, and approaches to status and institutions developed in the social sciences, Philip John Victor Davies examines the diverse factors which influenced the standing of individuals within the Spartiate community and assesses how great a role institutions played in determining a Spartiate's standing and to what extent Sparta was, as ancient accounts would suggest, significantly more institutionalized than other Greek societies. Placing Sparta in the context of the renewed interest in institutions and their social significance represented across multiple disciplines by the 'New Institutionalist turn', he presents a more dynamic understanding of the internal life of the Spartiate community, with a nuanced appreciation of the dimensions and limits of Sparta's exceptionality
Evaluation and uptake of an online ADHD psychoeducation training for primary care healthcare professionals: a four-year implementation report
Get PDFBackground: Health care professionals seldom receive training on neurodevelopmental conditions such as attention-deficit/hyperactivity disorder (ADHD). An online training was co-developed to address some of the gaps in knowledge and understanding in primary care. A randomized controlled trial demonstrated that the training increased knowledge and confidence and improved practice. Objective: This report highlights the implementation of the training in practice and follow-up 4 years post evaluation. Methods: The online ADHD training comprises 2 modules: “Understanding ADHD” and “The Role of the GP,” each taking approximately 45 minutes to complete. The training targets general practitioners primarily but is open to other health care professionals and parents. Feedback was collected through a survey at the end of the training, and the training has been widely adopted by various organizations internationally and nationally. Results: Between December 2019 and January 2024, the “Understanding ADHD” module was accessed more than 13,486 times, while the “Role of the GP” module was accessed 7018 times, primarily by users from the United States and the United Kingdom. Survey results from both modules showed positive feedback with high ratings for usefulness, likelihood to inform practice, and recommendation to colleagues. Some suggestions for improvement included reducing the negative focus on ADHD consequences and incorporating more positive aspects of ADHD. Conclusions: This ADHD online training program, despite facing implementation challenges, has seen positive outcomes, including international translation and high user ratings. Suggestions for improvement were received, but some were not feasible due to regional variations in ADHD pathways. The training’s impact extended beyond GPs to other health care professionals, although the COVID-19 pandemic posed obstacles to dissemination efforts. Nonetheless, ongoing plans aim to expand the training’s implementation globally
Caprock complexity and storage assurance: Advanced findings on CO₂ containment in the Bunter Sandstone Formation
Get PDFThe lower Triassic Bunter Sandstone Formation in the Southern North Sea is a promising site for CO2 storage. This reservoir has a complex structure, particularly in the overlying Haisborough Group caprock, along with fractured shale interlayers, chimney like-structures and fault features. This study highlighted the importance of incorporating all of this complexity into a model of a ‘Bunter-like’ storage site.Given the limited geological data on Bunter, four scenarios (Cases 1–4) were created to assess the impact of CO2 storage on the integrity of a complex caprock structure. This study revealed that fracture reactivation within variegated shale interlayers differed when comparing scenarios with a multi-layered caprock or a single caprock. With a multi-layered caprock, the CO2 plume was able to leak via the chimney region, whereas, with a single caprock, it did not. Furthermore, mineral dissolution/precipitation behaviour, particularly halite within the sub-layers of the shale interlayers, varied between the multi-layered and single caprock scenarios. Additionally, greater fault reactivation was observed in multi-layered caprocks compared to single caprock scenarios. With a multi-layered caprock, fault reactivation resulted in increased fault vertical and horizontal permeability than those observed in the single caprock scenario. The presence of a fault traversing several different layers of a multi-layer caprock led to different mineralogical behaviour than with a single caprock.This study emphasized the critical importance of intricate feedback interactions in systems with complex seal and reservoir geologies, as these interactions are essential for governing the overall behaviour of plume migration
Cross-Cultural Adaptation of the Brief Form of the Interpersonal Competence Questionnaire (ICQ-15) into Japanese
Get PDF(1) Background: This study aimed to translate and develop a culturally adapted Japanese version of the brief form of the Interpersonal Competence Questionnaire (ICQ-15) and to evaluate its psychometric properties for Japanese adults. (2) Methods: In the pilot test, we asked five Japanese university students to rate their understanding. Then, a final sample of 428 adults between 18 and 40 years old (45.1%male and 54.0% female) completed the Japanese version of the ICQ-15. To examine the psychometric properties of the ICQ-15, item analyses, confirmatory factor analysis, internal consistency analyses, and convergent and divergent validity analysis were performed. (3) Results: Although the items did not follow a normal distribution, most of them showed a good homogeneity index, suggesting good internal consistency between the items. The confirmatory factor analysis showed that the five-factor model had acceptable fit indices. Spearman correlations between the ICQ-15 and the Communication Skills Questionnaire (CSQ) supported its convergent validity, while correlations between the ICQ-15 and the Patient Health Questionnaire-9 (PHQ-9) supported its divergent validity. (4) Discussion and conclusions: A Japanese version of the ICQ-15 was developed showing good psychometric properties to be used to assess interpersonal competence in adults. This questionnaire demonstrated satisfactory internal consistency reliability among Japanese adults. A future study will investigate the criterion-related validity and temporal stability of the scale
Inter- and Intramolecular On-Surface Synthesis of Porphyrin-Based Nanostructures on Au(111) and Cu(111)
Get PDFSurface-confined synthesis provides alternative reaction pathways to those utilized within solution-phase chemistry and offers a route to extended molecular architectures with nanoscale dimensions and fascinating magnetic, electronic, and catalytic properties. However, these reaction pathways can be complex multistep processes, containing multiple reactive intermediates. Optimizing the selectivity and efficiency of such synthetic routes should be underpinned by detailed mechanistic insight, which requires submolecular spatial resolution in combination with details of chemical evolution throughout the reaction process. A key challenge is the application of an experimental methodology that allows in-depth study of multistep reactions. Here, we combine the spatial resolution of scanning tunneling microscopy with temperature-programmed photoelectron spectroscopies and present a comprehensive characterization of a multistep on-surface reaction utilizing a brominated porphyrin species. The porphyrin species employed is a highly functionalizable “molecular building block” from which nanostructured materials can be built, and within this work we identify key differences between the reaction on Cu(111) and Au(111). Intermolecular Ullmann-type coupling as well as intramolecular ring-closing and self-metalation are observed: specifically, on Au(111) we characterize self-metalation within covalently coupled assemblies of ring-closed TPP. Our results highlight the differing reactivity of Au(111) and Cu(111) and the strong influence of the substrate upon the reaction pathway and preferred products, and we provide spectroscopic and topographical characterization for all reaction steps
Benchmarking TERS and TEPL probes: towards a reference sample for quantification of near-field enhancement factors in gap and non-gap modes
Get PDFBenchmarking the near-field signal enhancement attained using plasmonic metal-coated atomic force microscopy (AFM) probes for tip-enhanced Raman spectroscopy (TERS) and tip-enhanced photoluminescence (TEPL) measurements is challenging given the absence of a suitable reference sample that is simple to prepare, easy to use and compatible with different instrument configurations. To this end, in this study, we have fabricated a flake of monolayer tungsten diselenide (1L-WSe2) stamped across the interface of gold and silver thin films on silicon dioxide and glass. We have demonstrated these samples to be effective for the facile determination of near-field Raman and photoluminescence contrast factors in both gap and non-gap mode, respectively. We show that the near-degenerate E12g + A1g and 2LA(M) peaks in the Raman spectra of WSe2 enable quantification of Raman contrast factors, with a ∼1.6-fold increase in TERS signal enhancement in gap mode, relative to non-gap mode, observed for a typical probe. Similar differences in the photoluminescence contrast factors were observed comparing in-contact and out-of-contact signal intensity ratios from gap and non-gap mode TEPL measurements. Moreover, in developing a reference methodology we found that the line shape of the TEPL profile was dependent upon the magnitude of the signal enhancement, with a disproportionate increase in the longer wavelength shoulder of the emission observed in gap mode. As this contribution to the asymmetric line shape is tentatively assigned to a dark exciton, which possesses an out-of-plane transition dipole moment, our TEPL measurements indicate that the directionality of the near-field enhancement provides a further handle enabling quantification of probe performance. Using samples prepared on glass, and comparing results obtained from two different instruments, each with a different excitation laser wavelength and optical access, we demonstrate the universal applicability of our reference material for sensitivity benchmarking of metallised AFM probes in both gap and non-gap mode, suitable for both reflection and transmission geometries, and across the range of laser wavelengths typically used for TERS and TEPL
Combinatorial discovery of microtopographical landscapes that resist biofilm formation through quorum sensing mediated autolubrication
Get PDFBio-instructive materials that intrinsically inhibit biofilm formation have significant anti-biofouling potential in industrial and healthcare settings. Since bacterial surface attachment is sensitive to surface topography, we experimentally surveyed 2176 combinatorially generated shapes embossed into polymers using an unbiased screen. This identified microtopographies that, in vitro, reduce colonization by pathogens associated with medical device-related infections by up to 15-fold compared to a flat polymer surface. Machine learning provided design rules, based on generalisable descriptors, for predicting biofilm-resistant microtopographies. On tracking single bacterial cells we observed that the motile behaviour of Pseudomonas aeruginosa is markedly different on anti-attachment microtopographies compared with pro-attachment or flat surfaces. Inactivation of Rhl-dependent quorum sensing in P. aeruginosa through deletion of rhlI or rhlR restored biofilm formation on the anti-attachment topographies due to the loss of rhamnolipid biosurfactant production. Exogenous provision of N-butanoyl-homoserine lactone to the rhlI mutant inhibited biofilm formation, as did genetic complementation of the rhlI, rhlR or rhlA mutants. These data are consistent with confinement-induced anti-adhesive rhamnolipid biosurfactant ‘autolubrication’. In a murine foreign body infection model, anti-attachment topographies are refractory to P. aeruginosa colonization. Our findings highlight the potential of simple topographical patterning of implanted medical devices for preventing biofilm associated infections
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