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This article analyzes four war-themed exhibitions in Ukraine’s two leading national museums and studies their role in documenting, interpreting, and exhibiting the Russo-Ukrainian war. This research intends to prove that since Russia’s full-scale invasion of Ukraine in 2022, museums have been conceptualizing the war through narratives of suffering and sacrifice, grounding tangible historical authenticity through the display of items such as war trophies and personal belongings. The narrative of suffering tends to be based on the opposition of “we” and “they,” where “we” focuses on civilian torment and resurrection as the main metaphor of physical and spiritual survival, and “they” are predominantly depicted as the military enemy, creating strong anti-Russian and anti-Soviet tendencies. The martyrdom narrative of sacrifice focuses on Ukraine’s (fallen) defenders, whose image is created by deep personalization, nationalization, and heroization. This article argues that musealization of the Russo-Ukrainian war exemplifies and represents “warring memory,” which is predetermined and justified by active engagement in an ongoing war while performing the functions of testimony, resilience, and mourning.
Ageing-in-place for persons with dementia and informal care-givers is encouraged by governments and society. However, individuals with non-Western migration backgrounds are at higher risk of dementia yet underrepresented in research and care. This study aims to identify ageing-in-place care preferences of persons with dementia and their informal care-givers in the Netherlands. Semi-structured interviews (n = 8 participants with dementia, n = 20 informal care-givers) were analyzed using reflexive thematic analysis. Findings reveal that informal care-givers feel a strong duty to care, assisting with various daily tasks. While they desire shared care with professionals, identifying concrete care needs is challenging, highlighting the need for proactive professional support. Participants also emphasized the importance of culturally sensitive in-home care, home adaptations, social care and accessible dementia information. Additionally, the emotional impact of dementia on care recipients and care-givers underscores the need for emotional support. These insights enhance understanding of the care preferences of persons with dementia and their informal care-givers, aiding more efficient and culturally responsive health service planning.
Revolutionary movements operated underground before and after national independence in many African countries. A communist party in Burkina Faso, the Parti communiste révolutionnaire voltaïque (PCRV), continued its underground political practice, despite democratic breakthrough. On the basis of long-term research engagement on popular struggle and the fight against impunity, the author used participant observation in street marches, meetings, sit-ins, and so on, and text analysis of pamphlets, declarations, and tracts to analyze how the PCRV is present in anti-imperialist struggles, while being absent in the public sphere.
Underwater robots conducting inspections require autonomous obstacle avoidance capabilities to ensure safe operations. Training methods based on reinforcement learning (RL) can effectively develop autonomous obstacle avoidance strategies for underwater robots; however, training in real environments carries significant risks and can easily result in robot damage. This paper proposes a Sim-to-Real pipeline for RL-based training of autonomous obstacle avoidance in underwater robots, addressing the challenges associated with training and deploying RL methods for obstacle avoidance in this context. We establish a simulation model and environment for underwater robot training based on the mathematical model of the robot, comprehensively reducing the gap between simulation and reality in terms of system inputs, modeling, and outputs. Experimental results demonstrate that our high-fidelity simulation system effectively facilitates the training of autonomous obstacle avoidance algorithms, achieving a 94% success rate in obstacle avoidance and collision-free operation exceeding 5000 steps in virtual environments. Directly transferring the trained strategy to a real robot successfully performed obstacle avoidance experiments in a pool, validating the effectiveness of our method for autonomous strategy training and sim-to-real transfer in underwater robots.
Wall-resolved large-eddy simulations of flow over an axisymmetric body of revolution (DARPA SUBOFF bare model) at $ \it{Re}_L=1.1\times 10^6$ are performed to investigate wall pressure fluctuations under the combined effects of transverse curvature and varying pressure gradients. Due to the coexistence of convex and concave streamwise curvatures, the flow in the stern region features alternating zones of favourable and adverse pressure gradients (APGs). The simulation validates experimental findings by Balantrapu et al. (2023, J. Fluid Mech., vol. 960, A28), confirming that in APG-dominant axisymmetric boundary layers without streamwise curvatures, the root mean square wall pressure fluctuations ($p_{w,rms}$) decrease downstream alongside the wall shear stress ($\tau _w$), maintaining a constant ratio $p_{w,rms}/\tau _{w}$. This study further finds that when streamwise curvatures and strong streamwise pressure gradient variations present, this relationship breaks down, suggesting that $\tau _w$ is not the dominant contributor to wall pressure fluctuations. Instead, the local maximum Reynolds shear stress $-\rho \langle u_su_n\rangle _{max }$ emerges as a more robust pressure scaling parameter. Normalising the wall pressure spectra by $-\rho \langle u_su_n\rangle _{max }$ yields better collapse across the entire stern region compared to conventional inner or mixed scaling methods. The magnitude and location of $-\rho \langle u_su_n\rangle _{max }$ significantly influence the spectral levels of wall pressure fluctuations across different frequency bands. As the turbulence intensity and $-\rho \langle u_su_n\rangle _{max }$ shift away from the wall, outer-layer structures – with larger spatial and temporal scales – dominate the coherence of wall pressure fluctuations. This mechanism drives sustained attenuation of high-frequency pressure fluctuations and a simultaneous increase in both the streamwise and transverse correlation lengths of wall pressure fluctuations over the stern region.
This article presents additional data to better understand the history of intercultural communication between the Yenisei people and the Han Chinese. Although the mysterious history and isolated culture of the ancient Kirghiz (Chinese Xiajiasi 黠戛斯) tribes at the Yenisei River Basin are little known to the world, ancient Chinese books and the artefacts with Chinese characters, unearthed in the Yenisei region, present a vivid picture of the Yenisei people’s foreign exchange history. This article approaches the Yenisei–Chinese cultural interaction from the perspective of the Yenisei Turk-Runic language and the date of the E77 inscription. The research material for this study is the E77 Yenisei inscription that is engraved on a Tang Dynasty bronze mirror called the Sanlejing 三樂鏡 (Lobed Mirror of Three Delights). The authors’ interpretations of the local Runic language on the E77 Yenisei inscription reveal Yenisei people’s knowledge about the Chinese iconic figure of Confucius, which blends into the Tibetan Bon religion as Kong tse or Kong tshe. Therefore, this article confirms the culture contact between the Yenisei and Han Chinese people during the Tang Dynasty.
Departing from simplistic portrayals of Chinese environmental governance as authoritarian, this study identifies a hybrid policy style that combines authoritarian environmentalism with policy experimentation, as evidenced in national park policy. A detailed examination of the North-East China Tiger and Leopard National Park shows that this hybrid increasingly tilts towards authoritarianism during implementation. To explain this dynamic, the study moves beyond the prevailing central–local lens and employs the tiao–kuai model, which captures the power relations among top leaders, central departments (tiao), and local governments (kuai). The analysis reveals that organizational interests centred on conservation have led central departments to expand their authority, marginalize local governments and narrow the space for experimentation, thereby suppressing community development demands. Even when top leaders intervene from above, the entrenched power structure of tiao and kuai still limits the effectiveness of corrective measures. The study contends that a hybrid policy style, supported by balanced power relations between tiao and kuai, is essential for reconciling conservation with development through environmental policy experimentation.
To show our experience in performing endoscopic-assisted maxillectomy (EAM), with the aim of facilitating delineation of tumour resection and improve the achievement of free tumour resection margins.
Methods
Patients undergoing EAM between 2021 and 2024 were reviewed. During the endoscopic approach, the medial and lateral plates of the pterygoid were drilled, taking as reference the superior margin of the inferior turbinate.
Results
Six patients underwent an EAM surgery. The maxillectomy was completed with an external transfacial approach in four patients and with a transoral approach in two. No intraoperative complications were observed. Five patients had postoperative flap dehiscence; two cases healed spontaneously and three cases required surgery.
Conclusion
EAM allows delimitation of the posterior limit of tumour resection in total or subtotal maxillectomies. This endoscopic approach facilitates the drilling of the pterygoid process to complete the posterior osteotomy, which is a complex manoeuvre during the exclusive external approach.
Recently, Nagib et al. (Phys. Fluids, vol. 36, no. 7, 2024, 075145) used indicator functions of streamwise normal stress profiles to identify the valid wall-distance and Reynolds number ranges for two models in direct numerical sumulation (DNS) of channel and pipe flows. Since such functions are challenging to construct from experimental data, we propose a simpler, more robust method better suited to experiments. Applied to the two leading models – logarithmic and power-law – for normal stresses in the ‘fitting region’ of wall-bounded flows, this method is tested on prominent experimental data sets in zero-pressure-gradient (ZPG) boundary layers and pipe flows across a wide Reynolds number range ($Re_\tau$). Valid regions for the models appear only for $Re_\tau \gtrapprox 10{\,}000$, with a lower bound $y^+_{in} \sim (Re_\tau )^{0.5}$ and $y^+_{in} \gtrapprox 400$. The upper bound is a fixed fraction of the boundary layer thickness or pipe radius, independent of $Re_\tau$. The power-law model is found to hold over a broader range, up to $Y \approx 0.4$ in ZPG and $Y \approx 0.5$ in pipe flows, compared with the logarithmic trend, which is formulated to be coincident with the classical logarithmic region for the mean flow ($Y \lessapprox 0.15$). A slightly higher exponent ($0.28$) than that of Chen & Sreenivasan (J. Fluid Mech. vol. 933, 2022, A20; J. Fluid Mech. vol. 976, 2023, A21) extends the power-law model’s validity and correcting for outer intermittency in ZPG flows further broadens it. Projections to the near-wall region of both models yield nearly identical predictions of near-wall peak stress across the highest available $Re_\tau$. These findings, alongside results from Monkewitz & Nagib (J. Fluid Mech. vol. 967, 2023, A15) and Baxerras et al. (J. Fluid Mech. vol. 987, 2024, R8), highlight the importance of nonlinear eddy growth and residual viscous effects in wall-bounded flow modelling, informing potential refinements to the logarithmic model, such as those proposed by Deshpande et al. (J. Fluid Mech. vol. 914, 2021, A5).
Transcatheter pulmonary valve replacement (TPVR) is often employed for patients who are poor surgical candidates. We present a case of posterior sternal protrusion into a surgically placed right ventricle to pulmonary artery conduit, making the patient a poor candidate for surgical replacement and leading to significant operator distress during ultimately successful TPVR.
Knowledge of the status of ecosystems is vital to help develop and implement conservation strategies. This is particularly relevant to the Arctic where the need for biodiversity conservation and monitoring has long been recognised, but where issues of local capacity and logistic barriers make surveys challenging. This paper demonstrates how long-term monitoring programmes outside the Arctic can contribute to developing composite trend indicators, using monitoring of annual abundance and population-level reproduction of species of migratory Arctic-breeding waterbirds on their temperate non-breeding areas. Using data from the UK and the Netherlands, countries with year-round waterbird monitoring schemes and supporting relevant shares of Arctic-breeding populations of waterbirds, we present example multi-species abundance and productivity indicators related to the migratory pathways used by different biogeographical populations of Arctic-breeding wildfowl and wader species in the East Atlantic Flyway. These composite trend indicators show that long-term increases in population size have slowed markedly in recent years and in several cases show declines over, at least, the last decade. These results constitute proof of concept. Some other non-Arctic countries located on the flyways of Arctic-breeding waterbirds also annually monitor abundance and breeding success, and we advocate that future development of “Arctic waterbird indicators” should be as inclusive of data as possible to derive the most robust outputs and help account for effects of current changes in non-breeding waterbird distributions. The incorporation of non-Arctic datasets into assessments of the status of Arctic biodiversity is recognised as highly desirable, because logistic constraints in monitoring within the Arctic region limit effective population-scale monitoring there, in effect enabling “monitoring at a distance”.
Despite constituting around 16% of the world’s population, we know little about the extent to which political parties encourage people with disabilities to participate in political parties. This article aims to fill that gap by providing a comparative analysis of political parties in Australia, Canada, New Zealand, and the United Kingdom. The research develops a framework for assessing the accessibility of political parties. The research finds evidence of activity in a small number of parties but finds relatively little evidence to suggest that parties are prioritizing this issue, especially when compared with the participation of other social groups. The article argues that we need greater research into the relationship between disability and political parties, concluding with a future research agenda.
Rayleigh–Taylor instability (RTI) caused by rarefaction waves not only features variable acceleration but also incorporates time-dependent density, which introduces great challenges in predicting the finger growth behaviours. In this work, we propose a model for predicting the single-mode finger behaviours by extending the Layzer potential-flow framework to account for time-dependent acceleration and density. Relative to the previous models, the present model can evaluate the effect of time-dependent density on finger growth, and can describe the growth behaviours of both bubbles and spikes in rarefaction-driven RTI flows. In addition, the time-dependent curvature of the finger tip as it evolves from its initial value to the quasi-steady value is quantified. To validate the model, rarefaction-tube experiments and numerical simulations are conducted across a wide range of initial conditions. The results show that the present model can accurately capture the amplitude growth and curvature evolution of bubbles and spikes across various density ratios. Moreover, both the present model and experiments demonstrate that the continuous density reduction in rarefaction-driven flows causes larger asymptotic velocities of bubbles and spikes, leading to higher Froude numbers relative to those under constant or time-dependent acceleration.
Transcatheter device closure of a large perimembranous ventricular septal defect with left-to-right shunt was attempted with an antegrade transvenous approach and a conventional arteriovenous loop facilitated, both of which were unsuccessful. We succeeded with an indigenous technique of advancing the delivery sheath towards the left ventricular apex from the venous side with the help of a cut pigtail, keeping the arteriovenous loop.
This study uses the diffusion analogy (Miyake, Sci. Rep., 5R-6, 1965, Univ. of Washington, Seattle, USA) to predict the full growth behaviour of internal boundary layers (IBLs) induced by a roughness change for neutrally – and especially stably – stratified boundary layers with finite thickness. The physics of the diffusion analogy shows that the streamwise variation of the IBL thickness is dictated by $\sigma _w/U$ at the interface, where $\sigma _w$ and $U$ represent wall-normal Reynolds stress and mean streamwise velocity, respectively. The existing variants of the model, summarised by Savelyev & Taylor (2005, Boundary-Layer Meteorol., vol. 115, pp. 1–25), are tailored to IBLs confined within the constant shear stress layer. To extend the applicability of the model to the outer region, we investigate the relation between $\sigma _w/U$ and $U/U_\infty$ in the outer region across varying stratification, where $U_\infty$ is the free-stream velocity. Our analysis reveals that wind tunnel data from a number of facilities collapse onto a master curve when $\sigma _w/U$ is premultiplied by a height-independent parameter, which is a function of the ratio of Monin–Obukhov length to the boundary layer thickness. The scaled $\sigma _w/U$ decreases inversely with $U/U_\infty$ in the surface layer, transitioning to a linear decrease as $U/U_\infty$ increases. The new model, which integrates these findings, along with the effects of streamline displacement and acceleration, captures the complete characteristics of IBLs as they develop within turbulent boundary layers of finite thickness.