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Infectious disease outbreak controllability: biological, social and public health factors
Get PDFEarly in an infectious disease outbreak, key policy questions include whether and how the outbreak can be brought under control. In the epidemiological modelling literature, analyses of outbreak controllability have often focused on metrics such as reproduction numbers (which quantify the number of infections generated by each infected individual). However, whether an outbreak can be controlled is a complex question, depending on both the precise definition of ‘under control’ used and numerous factors affecting decision-makers’ ability to implement transmission-reducing measures. Here, based on discussions at the Isaac Newton Institute’s ‘Modelling and inference for pandemic preparedness’ programme (5–30 August 2024), we describe a wide range of factors affecting outbreak controllability in practice. Programme participants came from institutions in ten countries, enabling discussions to reflect experiences of using models to inform policy in different settings. We divide the factors according to whether they relate predominantly to characteristics of the pathogen, host population or available interventions, and describe policy considerations when assessing whether an outbreak is controllable
Harnessing Generative AI for Sustainable Supply Chains: Lean, Circular and Green Perspectives
Get PDFGenerative artificial intelligence is playing a significant role in the transformation of digital ecosystems by reinventing the processes of content generation, process automation, product innovation and customer experience. At the same time that these technologies are becoming more integrated into routine operations, the focus has shifted to the ethical and environmental consequences associated with their widespread application. An investigation of the operational sustainability associated with the generative artificial intelligence systems would be crucial, as it would provide information about how these systems match ideals such as efficiency, circularity and environmental responsibility. We explore how users understand and engage with sustainability principles, specifically lean, circular and green operational frameworks within generative artificial intelligence environments. We collect user reviews of 72 recently launched generative AI platforms from 2022 to 2024 and utilise advanced machine learning methods, including Word2Vec modelling, sentiment and regression analysis, to reveal how text datasets reflect customer perceptions. We find that the lean theme is the most prominent feature of operational sustainability, with the highest sentiment score, followed by the green and circular themes. Our findings show that there is a growing respect among the general public for artificial intelligence systems that exhibit responsible and efficient design
[18F]fluorodeprenyl-D2 PET can detect and monitor astrogliosis in anti-LGI1-IgG autoimmune encephalitis
Get PDFPurpose
To explore whether detecting local astrogliosis using [18F]fluorodeprenyl-D2 ([18F]F-DED) positron-emission-tomography (PET) uncovers and monitors inflammatory lesions in patients with anti-leucine-rich glioma-inactivated 1 antibody (LGI1-ab) associated autoimmune encephalitis (AE).
Methods
Dynamic [18F]F-DED PET scans (0–60 min post-injection) were obtained from a cohort of 15 LGI1-AE patients, 9 of whom were re-examined during the disease course, and from 15 controls. PET quantification was performed by kinetic modelling with an image derived input function and calculation of simplified standardized uptake values (SUV). [18F]F-DED SUVr (referenced to the straight gyrus) were analyzed for LGl1-AE target regions, compared between baseline and follow-up PET scans, used to investigate asymmetry of the mesial temporal lobe (MTL), and correlated to routine clinical data.
Results
Simplified [18F]F-DED PET quantification of the 30–60 min time-frame showed excellent agreement with kinetic modelling of the full dynamic imaging protocol. In LGI1-AE patients, [18F]F-DED SUVr values were significantly increased by 16% in the MTL (p = .002) and by 12% in the cerebellum (p = .014). [18F]F-DED signals in the MTL significantly declined during the course of the disease (mean follow-up time: 15 months, p = .006). MTL asymmetry (> 5%) of [18F]F-DED SUVr was present in 8/15 of LGI1-AE patients compared to 1/15 controls (p < .001) and showed marked decline between baseline and follow-up in LGI1-AE patients.
Conclusion
This pilot study shows that [18F]F-DED PET is a promising tool to monitor regional astrogliosis in LGI1-AE patients and may provide a direct read-out of this important aspect of inflammatory disease activity
i-Motif, not G-quadruplex, stability regulates insulin expression
Get PDFThe insulin-linked polymorphic region (ILPR) is a variable number tandem repeat located in the promoter of the human insulin gene. This G-rich sequence can fold into four-stranded G-quadruplex DNA structures, while its complementary C-rich strand forms i-motifs. The ILPR varies in repeat number and sequence composition, but the relationship between sequence diversity, DNA structure, and insulin gene regulation remains poorly understood. Although both G-quadruplexes and i-motifs have been implicated in transcriptional control, their relative contributions, particularly when formed on complementary strands of the same locus, are unclear. Here, we characterized the structure and stability of nine ILPR-based sequences using biophysical techniques and luciferase reporter assays. We demonstrate that transcriptional activation in response to high glucose occurs only when both G-quadruplex and i-motif structures can form. Other combinations of structures do not induce transcription. Moreover, promoter activity correlated positively with i-motif stability, but not with G-quadruplex stability. These results suggest a model in which G-quadruplexes may act as an initiation site, while i-motifs act as modulators of insulin gene expression. Our findings underscore the importance of treating G-quadruplexes and i-motifs as a dynamic, interdependent system in both the regulation of gene expression and also the potential of these structures as therapeutic targets
Room-temperature polariton condensate in a quasi-2D hybrid perovskite
Get PDFQuasi-2D halide perovskites are chemically synthesized realizations of quantum well stacks with giant exciton oscillator strengths, tunable emission spectra, and very large exciton binding energies. While these features render quasi-2D halide perovskites a promising platform for room-temperature polaritonics, bosonic condensation and polariton lasing in quasi-2D perovskites have so far remained elusive at ambient conditions. Here, we demonstrate room-temperature cavity exciton-polariton condensation in mechanically exfoliated crystals of the quasi-2D Ruddlesden-Popper iodide perovskite (BA)2(MA)2Pb3I10 in an open optical microcavity. We observe a polariton condensation threshold of 0.41 µJ cm−2 per pulse and detect a strong non-linear response. Interferometric measurements confirm the spontaneous emergence of spatial coherence across the condensate with an associated first-order autocorrelation reaching 0.6 with 1 ps coherence time and an effective de Broglie wavelength of 13 µm. Our results lay the foundation for a new class of room-temperature polariton lasers based on quasi-2D halide perovskites with great potential for hetero-integration with other van-der-Waals materials and combination with photonic crystals or waveguides
Dual Frequency Liquid Crystals for Terahertz Power Stabilization
Get PDFLiquid crystal (LC) devices have a wide range of applications in electrically controlled adaptive optical devices. However, these devices have much slower operating speeds in the THz band than in the visible band, owing to the need for thicker active layers. A new device was fabricated using a dual-frequency LC which overcomes the speed limitations by allowing both electrically driven switch-on and switch-off transitions. This device showed a transmission of ~7% at 3.4 THz, with modulation depths of 60%, along with a maximum modulation rate of 20 Hz
Enhancing power density and cycle life of NMC811 battery cathodes via combined dense calendering and laser patterning
Get PDFThe charging time of Li-ion batteries is an important bottleneck in the wider adoption of electric vehicles (EVs). A common strategy to improve the rate performance is improving ion transport by patterning the electrode. However, these patterning methods usually increase the electrode porosity, thereby decreasing the volumetric energy density. In this work, we leverage the ability of Single Crystal LiNi0.8Mn0.1Co0.1O2 (SC-NMC811) electrodes to be calendered to higher packing densities than traditional cathodes, which then allows to offset additional porosity introduced by electrode patterning. We calendar SC-NMC811 electrodes to a 25% porosity and then introduce hole patterns spaced 100 to 600 µm apart using laser processing with a goal to maintain average porosities below 30%. As expected, we found systematic improvements in the rate performance with increasing hole density and used operando charge photometry to explore the limits of mass transport in the regions surrounding the holes but interestingly, we also observe improved capacity retention when using patterned electrodes. We found that there is less cathode lattice oxygen loss when using patterned cathodes, this in turn reduces transition metal shuttling reduces anode solid electrolyte interphase (SEI) impedance growth. We demonstrated a reduction in oxygen loss by both electron energy loss spectroscopy (EELS) mapping, X-ray diffraction (XRD) mapping and X-ray diffraction computed tomography (XRD-CT). Overall, SC-NMC811 electrode's ability to withstand over-calendering offers the opportunity to introduce laser patterned holes while maintaining the average porosity below 30%. This increases both the rate performance and longevity of the electrodes
A Indologia Soviética e a ascensão da “filologia insurgente”
Get PDFO artigo discute o desenvolvimento da “filologia insurgente” no início da Rússia Soviética e sua relação com os Estudos Orientais. Após alguns pontos históricos e teóricos gerais, discute-se o caráter da Indologia soviética inicial, com referência especial ao trabalho de F. I. Shcherbatskoi e à influência do neokantianismo. Em seguida, discutem-se as mudanças na Indologia no início da URSS, com atenção especial para A. P. Barannikov. O budologista e membro do “Círculo de Bakhtin”, M. I. Tubianskii, é considerado uma figura de transição, com referência especial ao seu trabalho sobre Rabindranath Tagore. São feitas conexões com o surgimento de uma tendência “insurgente” entre os intelectuais anticastas (Phule, Thass, Ambedkar) e são apresentadas algumas reflexões finais sobre a relevância do trabalho de Bakhtin para esse campo.
The article discusses the development of “insurgent philology” in early Soviet Russia and its relationship to Oriental Studies. After some general historical and theoretical points, the character of early Soviet Indology is discussed, with particular reference to the work of F. I. Shcherbatskoi and the influence of neo-Kantianism. A discussion of changes in Indology in the early USSR follows, with particular attention given to A. P. Barannikov. Buddhologist and member of the “Bakhtin Circle,” M. I. Tubianskii is considered as a transitional figure, with particular reference to his work on Rabindranath Tagore. Connections with the emergence of an “insurgent” trend among anti-caste intellectuals (Phule, Thass, Ambedkar) are made and some final reflections on the relevance of Bakhtin’s work to this field are given
The Separate Grounds of Competence
Get PDFWhen a person is competent, they can exercise their autonomy rights, including waiving claims against interference by giving consent. Non-competent persons, by contrast, lack these autonomy rights, which means that others are permitted to make certain decisions for them. What grounds this gulf between the rights of competent and non-competent persons? In this paper, we present a novel account of the capacities that underlie competence. Competence comprises two distinct rights: a power to alter claims and a claim against paternalistic interference with one’s decisions. While existing accounts appear to assume that the same capacities underlie both features of agential control, we argue that they have separate grounds. The capacity that grounds the power to alter claims is the capacity to value, whereas the capacity that grounds the claim against paternalistic interference is the more substantial capacity to be responsible for one’s actions. By separating these normative grounds, we solve a problem that plagues Common Grounds views. Our Separate Grounds account can explain why and in what way the decisions of persons with marginal autonomy should be respected without sacrificing the need to protect them from harm
Secondary electron hyperspectral imaging (SEHI) in FIB – SEM for proton exchange membrane fuel cells technology
Get PDFThe performance of proton exchange membrane (PEM) fuel cells critically depends on the microstructure and chemistry of their constituent materials, particularly the catalyst layer (CL), carbon black (CB), ionomer films, and reinforced membranes. However, the highly heterogeneous and nanoscale nature of these components presents significant challenges for existing characterization techniques. This study explores the application of Secondary Electron Hyperspectral Imaging (SEHI) in focused ion beam–scanning electron microscopy (FIB–SEM) to address these limitations. SEHI uniquely integrates chemical sensitivity, surface specificity, and nanoscale spatial resolution, enabling detailed insights into key functional materials. Carbon black analysis revealed the spatial distribution of graphitised regions and surface functional groups, such as CO bonding, which are critical for optimizing electron transport and catalyst stability. For ionomer films and membranes, SEHI identified and mapped chemical differences between the ionomer matrix and its polybenzimidazole (PBI) reinforcement, distinguishing nitrogen species and surface functionalities. This capability facilitates a deeper understanding of how membrane composition and structure influence conductivity and durability. The results demonstrate SEHI’s potential as a transformative tool for the nanoscale characterization of PEM fuel cell components, providing critical insights for the design and optimization of high-performance, durable fuel cells
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