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Artificial intelligence (AI) requires new ways of evaluating national technology use and strategy for African nations. We conduct a survey of existing “readiness” assessments both for general digital adoption and AI policy in particular. We conclude that existing global readiness assessments do not fully capture African states’ progress in AI readiness and lay the groundwork for how assessments can be better used for the African context. We consider the extent to which these indicators map to the African context and what these indicators miss in capturing African states’ on-the-ground work in meeting AI capability. Through case studies of four African nations of diverse geographic and economic dimensions, we identify nuances missed by global assessments and offer high-level policy considerations for how states can best improve their AI readiness standards and prepare their societies to capture the benefits of AI.
Wearable pressure sensors with high sensitivity, fast response time, and low detection limit have great potential for blood pressure monitoring and early diagnosis of hypertension. This article introduces a piezoresistive pressure sensor based on carbon nanotubes (CNTs), polyaniline (PAni), and fabric (CNT/PAni/fabric) for health monitoring applications. This sensor is made by using two layers of linen fabric coated with CNT and PAni. These layers are placed on a polyester fabric substrate. One of the coated layers has a mesh structure, which increases the sensitivity of the sensor and lowers its detection limit. The CNT/PAni/fabric sensor has a high sensitivity of 2.035 kPa−1 at pressures from 0 to 0.2 kPa, a response time of 290 ms, and a detection limit of 1.5 Pa. These features make it suitable for measuring blood pressure. The results obtained by measuring blood pressure using the pulse transit time method on four people, compared with the values obtained using the digital sphygmomanometer, show a discrepancy ranging between 0.019% and 1.62%. Also, the average error and standard deviation for the sensor measurement in systolic and diastolic pressures are 0.56 ± 0.33 and 0.57 ± 0.46, respectively, which shows that measurement with this sensor can be an alternative to existing devices.
Revision of the type species of the Early Ordovician (Tulean, late Tremadocian) bathyurid trilobite Licnocephala Ross, 1951 demonstrates that it has significantly different morphology than that ascribed to it in the earlier literature, which was based largely on species now assigned to a different genus. In addition to the type species, L. bicornuta Ross, 1951, which is fully revised on the basis of new material, four species, all apparently new, have been recovered, two of which, L. ngi n. sp. and L. bradleyi n. sp., are well enough known to formally name. The overall phylogenetic structure of bathyurids is yet to be determined, but several apparent clades can now be recognized and are discussed. Among these is what is termed the “Chapmanopyge group,” including Chapmanopyge Fortey and Bruton, 2013, Punka Fortey, 1979, Uromystrum Whittington, 1953, and Licnocephala. These genera are united in the occurrence of much of the anterior cephalic border on the librigenal anterior projection, with most of the anterior margin of the cranidium representing the suture, the possession of very short (exsag.) strap-like posterior cranidial projections, and extremely narrow visual surfaces. A fifth genus of the group, Ibexocephala n. gen., is represented by two new species, I. lossoae (type species) and I. dekosterae. The taxon features a remarkable cranidial morphology involving a strong deflection of the posteriormost part of the cranidium from the anterior part in sagittal profile.
It is often claimed that gender data gaps (GDGs) are unjust, but the nature of the injustice has not been interrogated. We argue that injustices arising from such data gaps are not merely socio-political but also epistemic: they arbitrarily skew the epistemic landscape in favour of one group over another. GDGs place a greater epistemic burden on women and gender minorities; they have to do more to avoid error and the pay-off is worse: they have a smaller pool of true beliefs on which to act. We suggest that there are both pragmatic and conceptual reasons to differentiate the injustice arising from GDGs from other more familiar varieties (such as testimonial and hermeneutical injustice), and so we introduce the new concept of epistemic deprivation to capture this injustice.
Early learning of a second language at home has been found to be beneficial for children’s cognitive development, including their ability to ascribe mental states to others. We investigated whether second language learning in an educational setting can accelerate children’s sensitivity to a communication partner’s perspective and whether the amount of exposure to second language education makes a difference. We tested three groups of English monolingual four-five year old children with varying language exposure at the beginning of their first year at primary school and 24 weeks later. Children attending bilingual schools and children with weekly second language lessons exhibited similar accelerated development of communicative perspective-taking skills compared to children without second language provision. Such advances were not related to other cognitive advances. Thus, limited foreign language teaching might boost young children’s development in communicative perspective-taking skills, providing an enhanced basis for their social competence development.
We show that March’s criterion for the existence of a bounded nonconstant harmonic function on a weak model (that is, $\mathbb {R}^n$ with a rotationally symmetric metric) is also a necessary and sufficient condition for the solvability of the Dirichlet problem at infinity on a family of metrics that generalise metrics with rotational symmetry on $\mathbb {R}^n$. When the Dirichlet problem at infinity is not solvable, we prove some quantitative estimates on how fast a nonconstant harmonic function must grow.
Data tax (DT) could re-establish states’ legitimacy by governing economic actors and promoting social solidarity and welfare through benefits. However, the overall impact of DT will depend on decisions about what social benefits DT funds (universal basic income or less expensive public goods) and whether benefits will entrench or challenge harmful business models and practices. Focusing on the right to science (RtS), the paper argues that DT could realise the RtS in the digital age through taxation that exacted not only data rent but also rent on the scientific heritage. Finally, the paper emphasises the need for international coordination to ensure that DT is equitably shared among developed and less developed countries.
Herbicide-resistant weeds threaten modern agriculture production. In Michigan, horseweed (Erigeron canadensis L.; syn. Conyza canadensis (L.) Cronq.) is among the most troublesome weeds, and glyphosate was widely used to control E. canadensis. Due to extreme selection pressure imposed by heavy glyphosate usage, glyphosate-resistant E. canadensis is widespread. New technologies to control resistant E. canadensis are being introduced in the form of multiple herbicide-resistance traits into glyphosate-resistant soybean (e.g. dicamba or 2,4-D choline). These new soybean [Glycine max (L.) Merr.] varieties will likely increase the use of 2,4-D and dicamba thus increasing the resistance selection pressure in E. canadensis. Predicting agronomic factors that drive herbicide-resistance evolution can serve as an effective proactive tool to advise practitioners to modify management strategies. Therefore, the objectives of this study are: 1) conduct dose-response assays to assess current resistance spectrum of E. canadensis collected in Michigan and 2) predict and determine the main factors in row crop production that contribute to resistance evolution in these accessions. Dose-response assays were conducted to evaluate the herbicide sensitivity spectrum to glyphosate, dicamba, and 2,4-D in 20 E. canadensis accessions collected from eight Michigan counties. Out of the 20 accessions, 60% were resistant to glyphosate, 35% to 2,4-D, and 20% to dicamba. Pearson’s correlation coefficient of dose-response values were positive in all comparisons (2,4-D-dicamba, r = 0.35; dicamba-glyphosate, r = 0.15; 2,4-D-glyphosate, r = 0.21). Dose-response data were integrated in odds ratio analyses to access the influence that previous management history had on the occurrence of resistance. Out of the significant pairwise comparisons, 44% were related to crop rotation frequency, 33% to previous herbicide-resistance status, and 22% to location collected. Results highlight that growers have the ability to proactively manage herbicide-resistance evolution progression of E. canadensis in Michigan by adopting integrated weed management techniques to slow successive selection events that occur in low diversity management systems.
Albeit laboratory experiments and numerical simulations have proven themselves successful in enhancing our understanding of long-living large-scale flow structures in horizontally extended Rayleigh–Bénard convection, some discrepancies with respect to their size and induced heat transfer remain. This study traces these discrepancies back to their origins. We start by generating a digital twin of one standard experimental set-up. This twin is subsequently simplified in steps to understand the effect of non-ideal thermal boundary conditions, and the experimental measurement procedure is mimicked using numerical data. Although this allows for explaining the increased observed size of the flow structures in the experiment relative to past numerical simulations, our data suggests that the vertical velocity magnitude has been underestimated in the experiments. A subsequent reassessment of the latter's original data reveals an incorrect calibration model. The reprocessed data show a relative increase in $u_{z}$ of roughly $24\,\%$, resolving the previously observed discrepancies. This digital twin of a laboratory experiment for thermal convection at Rayleigh numbers $Ra = \{ 2, 4, 7 \} \times 10^{5}$, a Prandtl number $Pr = 7.1$ and an aspect ratio $\varGamma = 25$ highlights the role of different thermal boundary conditions as well as a reliable calibration and measurement procedure.
The cosmological argument for the existence of God seems to have significant intuitive resonance. According to a familiar version of the cosmological argument, there must be some explanation for why the universe exists, and God provides the explanation. This argument seems to depend on the Principle of Sufficient Reason (PSR), according to which, if something exists, there must be an explanation for why it exists. As we detail, recent evidence indicates that people presuppose something like the PSR in their explanatory outlook. However, the other key part of the cosmological argument is that God is supposed to be self-explanatory – God’s existence is necessary. We examine this empirically and find that people do not generally think that the existence of God is necessary in the sense relevant for the cosmological argument.
Taking inspiration from the work of Douglass North, much institutional research attempts a distinction between ‘formal’ and ‘informal’ institutions. North often associated ‘formal institutions’ with rules enforced through a legal system. It is suggested here that this lead should be followed and refined. In which case ‘legal system’ and ‘law’ require definitions. An alternative claim, that ‘formal’ basically means ‘written down’, is arguably less useful. Stressing the importance of clear definitions in this area, this paper considers a case where slight modifications yield strikingly different results. Some options concerning the meanings of ‘culture’ and their relation to institutions are briefly noted. Changes in, and interactions between, ‘formal’ and ‘informal’ institutions are considered, with illustrative examples. Contrary to some authors, informal institutions can sometimes change rapidly, in some cases in response to state legislation.
In this paper, I explore how two recent politically charged deaths—those of George Floyd and Ashli Babbitt—illuminate the broader dynamics inherent in the concept of political martyrdom and its relationship to American democracy. Political martyrdom (as distinct from that associated with religious communities) offers martyrs a life beyond the grave, not by promising eternal life or paradise, but by ensuring them a role in a community’s collective memory. It involves three components: death, in what we might call “unnatural” circumstances, generally connected to an individual’s identity (or identities) or political commitments; consecration of that death, embedding it in a community’s collective memory and ascribing to it transcendent meaning; and transmission, the passing down of martyrdom narratives over time through media, ritual, and commemorative practices. The paper uses the examples of Floyd and Babbitt to illustrate the value of this conceptual category, one that focuses less on the personal qualities of individuals and more on communities’ narrations of their lives and deaths; highlights such narratives’ capacity to build collective identities over time, often in contexts far removed from the martyrs’ own lives and deaths; and offers new interpretive lenses for considering twenty-first-century issues of systemic violence and structural injustice.
We present PCFTL (Probabilistic CounterFactual Temporal Logic), a new probabilistic temporal logic for the verification of Markov Decision Processes (MDP). PCFTL introduces operators for causal inference, allowing us to express interventional and counterfactual queries. Given a path formula φ, an interventional property is concerned with the satisfaction probability of φ if we apply a particular change I to the MDP (e.g., switching to a different policy); a counterfactual formula allows us to compute, given an observed MDP path τ, what the outcome of φ would have been had we applied I in the past and under the same random factors that led to observing τ. Our approach represents a departure from existing probabilistic temporal logics that do not support such counterfactual reasoning. From a syntactic viewpoint, we introduce a counterfactual operator that subsumes both interventional and counterfactual probabilities as well as the traditional probabilistic operator. This makes our logic strictly more expressive than PCTL⋆. The semantics of PCFTL rely on a structural causal model translation of the MDP, which provides a representation amenable to counterfactual inference. We evaluate PCFTL in the context of safe reinforcement learning using a benchmark of grid-world models.
The genus Rhinebothrium (Cestoda: Rhinebothriidea) comprises tapeworm species parasitizing elasmobranch hosts, particularly batoids. Despite numerous recent findings regarding the ecological importance of marine fish parasites throughout the world, the biodiversity of cestodes inhabiting fishes of the Persian Gulf and the Gulf of Oman remains understudied. Here, two new species of Rhinebothrium from stingrays from the Persian Gulf and Gulf of Oman are described: Rhinebothrium gossi sp. nov. and Rhinebothrium palmeri sp. nov. from Maculabatis arabica and Maculabatis randalli, respectively. However, each new cestode species is found with a lower frequency in the other host species, too. These new species were already subjected to a molecular analysis and the revealed genetic distinctiveness requires detailed morphological examinations at the species level. A combination of morphomeristic characteristics including body size, scolex features, proglottid morphology, and reproductive structures distinguish the new species from the other congeners. Although these new species are morphologically similar, however, they differ from each other in the number of testes (6–8 and 8–14), and bothridial loculi (50 and 42 in R. gossi sp. nov. and R. palmeri sp. nov., respectively). These findings contribute to our understanding of marine cestode diversity and underscore the importance of further research in this ecologically significant region.
We solve ‘half’ the problem of finding three-dimensional quasisymmetric magnetic fields that do not necessarily satisfy magnetohydrostatic force balance. This involves determining which hidden symmetries are admissible as quasisymmetries, and then showing explicitly how to construct quasisymmetric magnetic fields given an admissible symmetry. The admissibility conditions take the form of a system of overdetermined nonlinear partial differential equations involving second derivatives of the symmetry's infinitesimal generator.