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This article studies the geological structure, mineralogical composition, genesis, and sorption properties of Khonguruu zeolite deposit (Republic of Sakha, Russia). Although it is one of the largest developed deposits in Russia, detailed studies of the mineral composition and physicochemical properties have not been conducted previously, which limits its industrial potential. Zeolites were studied with X-ray diffraction (XRD), scanning electron microscopy (SEM), differential thermal analysis (DTA), X-ray fluorescence spectrometry (XRF), Fourier transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) and cation exchange capacity (CEC) analyses. Experiments on the sorption of radioactive cesium were also carried out. Zeolites formed four beds with an average content of 50–85%. The main focus of this study is on the detailed investigation of its mineral composition. These data, together with the analyses of ion-exchange complexes and color, provided an opportunity to distinguish between different types of zeolites. The zeolite minerals are represented by heulandite-1, heulandite-2 and, to a lesser extent, clinoptilolite. For the first time, a significant presence of amorphous silica was demonstrated in zeolite samples and used for correction of the crystallochemical formula of zeolites. On the basis of exchangeable cations composition, two main types of zeolites were found at the deposit: alkaline and alkaline-earth. The CEC of the zeolites ranged from 139 to 214 cmolc kg–1 and high 137Cs sorption. The zeolites have a volcanogenic-sedimentary genesis and were formed from ash material of basic and acidic composition in coastal sea waters with alternating conditions of low and high salinity. Based on the data obtained, it can be concluded that the alkaline raw material can be used as a sorbent for wastewater treatment.
Epilepsy affects 50 million people worldwide and is frequently associated with memory impairment, contributing significantly to reduced quality of life. Memory difficulties are commonly reported across epilepsy syndromes and may coexist with anxiety, reduced self-esteem and social withdrawal. While temporal lobe epilepsy is often highlighted due to the crucial role of mesial temporal structures in memory processing, memory functions also rely on distributed neural networks extending beyond the temporal lobe. A common concern among patients with epilepsy, discussed during clinic visits, relates to memory deficits. They often inquire if these deficits are linked to anti-seizure medications (ASMs), controlled or uncontrolled epilepsy or the underlying cause of their condition. It is crucial for the treating physician to understand the types of memory, the brain structures and circuits involved and how epilepsy, ASMs, structural brain lesions and neuromodulatory interventions affect the processes of acquiring and encoding memory. In this paper, we provide a brief yet clinically relevant overview of memory and the factors contributing to memory deficits. This publication is intended for both general physicians and specialists who care for patients with epilepsy and other neurological disorders. While previous studies suggest that epilepsy can affect memory, other contributing factors must also be considered. This paper will explore the fundamentals of memory, the effects of brain lesions and how treatments such as ASMs, ablative procedures, resective epilepsy surgery and neuromodulatory devices influence these processes. It also discusses cognitive rehabilitation and strategies to help patients cope with memory deficits and highlights areas for future research.
In high-dimensional (HD) sparse linear regression, parameter selection and estimation are addressed using a constraint $l_0$ on the direction of the parameter vector. We begin by establishing a general result that identifies this direction through the leading generalized eigenspace of specific measurable matrices. Using this result, we propose a novel approach to the selection of the best subsets by solving an empirical generalized eigenvalue problem to estimate the direction of the HD parameter. We then introduce a new estimator based on the RIFLE algorithm, providing a non-asymptotic bound for the estimation risk, minimax convergence, and a central limit theorem. Simulations demonstrate the superiority of our method over existing $l_0$-constrained estimators.
This review essay critically examines three recent books on the digitalization and datafication of humanitarian action: #Help, Humanitarian Extractivism, and Technocolonialism. Each monograph offers a compelling analysis of the myriad ways that humanitarians’ use of digital technologies has reshaped governance and the international order, created new risks, and exacerbated power imbalances. Fundamentally, each book concludes that the various transformations technology has wrought in humanitarianism are, at best, unintended, inconsistent, or unfulfilled in their impact and, at worst, deeply problematic. Setting aside the books’ contributions, each leaves out two important elements. First, in selecting examples, the authors leave mostly unanswered the question of what, if any, positive impacts data and technology have had on or for humanitarian response and those whom it is intended to help. Second, each is mostly silent with regard to practical steps that can be taken to address its critiques, with only Technocolonialism offering three broad avenues for reform. In the context of the current crisis in the humanitarian sector, with the closure of USAID and dramatic declines in funding, there is a need for pragmatic options for the future that, by necessity, involve a creative reimagining of the digital infrastructures underpinning the humanitarian response.
The impact of spanwise surface temperature heterogeneity on steady stably stratified Ekman layers is systematically studied using large-eddy simulation (LES). Spanwise varying strips of high and low surface temperature are imposed in idealised LES of stable boundary layers (SBLs), in which a steady state results from a balance between cooling at the ground and heating due to imposed synoptic subsidence. Consistent with previous studies on channel flows with streamwise-aligned surface heterogeneity (e.g. Bon & Meyers, J. Fluid Mech. 2022, pp. 1–38), large-scale secondary circulations develop and extend deep into the stable Ekman layer. Coriolis effects enhance counterclockwise circulations while reducing clockwise ones, thereby tilting the mean secondary flow structures towards the left (in the northern hemisphere). Nevertheless, for the considered surface temperature contrasts of 1.5–12 K and spanwise wavelengths of 100–800 m, the impact on mean SBL structure is substantial. As the surface temperature difference or strip width increases, secondary flows and dispersive fluxes strengthen, eventually reaching the top of the SBL. This augmentation further enhances near-surface gradients, elevates SBL depths and low-level jets, and reduces mean surface heat fluxes. Novel correlations between characteristics of the surface heterogeneity and their impact on the mean SBL structure are proposed. Moreover, the local surface fluxes are shown to significantly deviate from the mean, highlighting that horizontally averaged SBL properties do not capture all important physical processes in a heterogeneous flow. Overall, this work affirms that thermal surface heterogeneity is a crucial factor in governing transport processes within the atmospheric stable boundary layer.
The compactly supported $\mathbb {A}^1$-Euler characteristic, introduced by Hoyois and later refined by Levine and others, is an analogue in motivic homotopy theory of the classical Euler characteristic of complex topological manifolds. It is an invariant on the Grothendieck ring of varieties $\mathrm {K}_0(\mathrm {Var}_k)$ taking values in the Grothendieck-Witt ring $\mathrm {GW}(k)$ of the base field k. The former ring has a natural power structure induced by symmetric powers of varieties. In a recent preprint, the first author and Pál construct a power structure on $\mathrm {GW}(k)$ and show that the compactly supported $\mathbb {A}^1$-Euler characteristic respects these two power structures for $0$-dimensional varieties, or equivalently étale k-algebras. In this paper, we define the class $\mathrm {Sym}_k$ of symmetrisable varieties to be those varieties for which the compactly supported $\mathbb {A}^1$-Euler characteristic respects the power structures and study the algebraic properties of the subring $\mathrm {K}_0(\mathrm {Sym}_k)$ of symmetrisable varieties. We show that it includes all cellular varieties, and even linear varieties as introduced by Totaro. Moreover, we show that it includes non-linear varieties such as elliptic curves. As an application of our main result, we compute the compactly supported $\mathbb {A}^1$-Euler characteristics of symmetric powers of Grassmannians and certain del Pezzo surfaces.
In this paper, I argue that shame (verecundia) functions as a key passion, revealing the complex structure of human affectivity and shedding new light on the understanding of Aquinas’s theory of the passions. In numerous passions, such as sadness, fear, or pleasure, the appetitive motion and the accompanying bodily changes follow the same direction – expansion or contraction – according to a common sensory basis. In contrast, shame presents a clear exception: while the appetite contracts inward, vital spirit and heat expand outward, producing blushing. According to Aquinas, passions are motions of the sensitive appetite accompanied by bodily change. Although shame retains this structure, its change is nevertheless formed through the redundantia of the higher faculties, which leads me to argue that it occupies an intermediate position between ‘passions properly speaking’ and ‘purely intellectual pseudo-passions’. By analyzing shame in this light, I demonstrate that human passions should be understood not as purely natural or rational, but as complex intersections of both.
Africa-West migration is on the increase. For many young Nigerians, emigration is a goal that must be achieved by any means possible, regardless of the realities in receiving countries. With exposure to new environments, migrants can identify with their home culture, assimilate the lifestyles of the host country, or find a middle ground. This study examined the patterns of self-identification among Nigerian migrants and their understanding of the complex concept of “immigrant integration.” The study explores the (dis)connections between migrants’ self-identification and their viewpoint of immigrant integration. The study analyzed thirty qualitative interviews with sixteen Nigerian migrants in the United States (US) and fourteen in the United Kingdom (UK). The study employed a thematic analysis approach and utilized NVivo (version 14) to manage the data, finding that most participants reported a stronger allegiance to Nigerian culture than to the host country, with their justifications primarily revolving around food, social life, and citizenship. Others identified fully with the host country, primarily because of unpleasant experiences in their country of origin. Using W. E. B. Du Bois’s concept of “double consciousness,” the study reveals that, despite an overwhelming identification with their country of origin, most participants conceived of immigrant integration as assimilation—a process of “sinking,” “learning,” “assimilating,” and “adopting” the culture of the host country. The study suggests that migrants’ identity and identification are inherently fluid. The disconnect between self-identification and the understanding of integration is attributed to the framing of immigrant integration by host governments and migrants’ urge for a positive migration experience in the host country.
The two-dimensional to three-dimensional wake transition of a circular cylinder in a sinusoidal oscillatory flow arises from the Honji instability at a critical Keulegan–Carpenter number (denoted $\textit{KC}_{cr}$) with a corresponding critical spanwise wavelength (denoted $\lambda _{cr}$) for a given Stokes number (denoted $\beta$) larger than approximately 50. However, significant discrepancies in the $\textit{KC}_{cr}$ and $\lambda _{cr}$ values exist among the theoretical predictions by Hall (J. Fluid Mech., vol. 146, 1984, pp. 347–367), empirical formulae by Sarpkaya (J. Fluid Mech., vol. 457, 2002, pp. 157–180) and other experimental and numerical results in the literature. These long-standing discrepancies are addressed in this study, and new equations for $\textit{KC}_{cr}$ and $\lambda _{cr}$ are proposed for $\beta = 55$–$10^{6}$. The present $\textit{KC}_{cr}$ and $\lambda _{cr}$ values agree well with the Floquet analysis results of Elston et al. (J. Fluid Mech., vol. 550, 2006, pp. 359–389) for $\beta \sim 50$–$100$, and asymptotically converge to theoretical predictions by Hall (1984) as $\beta \to \infty$, but deviate significantly from the empirical formulae by Sarpkaya (2002). The underlying physical mechanisms for these deviations are elucidated. In addition, we reproduce the quasi-coherent structure (QCS) numerically for the first time, and demonstrate that the QCS observed by Sarpkaya (2002), where transient Honji vortices become pronounced near peak flow velocities but diminish during deceleration, is physically induced by ambient disturbances inevitably contained in physical experiments, such that $\textit{KC}_{cr}$ given by Sarpkaya (2002) is specific to the level of disturbance in his experimental setting and is somewhat arbitrary.
In the article, the unsteady flow phenomenon of self-excited and forced oscillations in a rectangular diverging isolator is studied by using large eddy simulation, and the shock train region is analysed particularly. Self-excited oscillations are analysed under four pressure ratios, with pressure statistically processed to reveal shock train oscillation characteristics. The interference factors of the external environment on the unsteady flow in the isolator are investigated, and the function of upstream disturbance and downstream disturbance on the shock train oscillation is studied. Both disturbance types show that pressure amplitude increases oscillation amplitude, while frequency variations have opposing effects. Due to mismatched response speeds, low-frequency disturbances intensify oscillations, whereas high-frequency ones suppress them. The difference is that the pressure frequency excitation upstream is transmitted along the flow direction and directly acts on the shock train in the trough period of each unsteady pressure transformation, which intensifies the negative effect on shock train oscillations. The downstream disturbance arrives at the shock train region after passing through the complex flow coupling in the mixing region. The superposition of the external pressure excitation frequency and the mixing region makes the response of the shock train slower leading to a weakening effect of the shock train oscillation. Moreover, the unsteady flow develops in the mixing district and transmits upstream, and the inhibition effect is stronger than that of upstream pressure frequency excitation.
Se presentan los detalles del rescate de una tumba parcialmente saqueada, localizada al pie del Jasi Hablador —un gran paredón de areniscas terciarias, ubicado al norte del Departamento de Belén, Catamarca, Argentina—, y los primeros avances en el análisis de los materiales recuperados. Fue posible rescatar más de 30 fragmentos de textiles, abundantes restos óseos humanos —algunos con tejidos blandos— y distintos materiales arqueobotánicos secos. Una datación radiocarbónica sobre una muestra textil arrojó una fecha para mediados del siglo quince dC, coincidente con la ocupación inka en la región. A partir de estos primeros resultados, se discute la relación de este espacio funerario con el paisaje del Jasi Hablador en el contexto más amplio de la conquista inka. La preservación de los materiales orgánicos en el sitio es excepcional para la región, por lo cual, la continuidad de estos estudios aportará información de gran relevancia sobre los vínculos entre los grupos locales y el imperio inka.
Data-embedded instruments that couple sensing, modelling and sound production are increasingly used in electroacoustic practice, yet their ethical and cultural configurations remain under-analysed. This article develops an ethical-embodied framework for examining how particular data, sensing and mapping arrangements configure relations of care, listening and musical agency. Drawing on feminist and decolonial listening practices, disability and critical data studies and accounts of embodied instrumentality, it combines a selective genealogy of electroacoustic and globally situated practices with a mid-level comparative lens that treats its technical axes as heuristic rather than taxonomic. Case vignettes analyse works using gesture tracking, electromyography (EMG) and brain–computer interfaces (BCI), audience-sensing installations and machine-learning vocal systems, alongside the author’s own data-embedded instrument. Across these examples, the analysis shows how similar technologies can reproduce or contest institutional surveillance, extractivism and aesthetic normativity and outlines implications for the design, evaluation and teaching of data-mediated musical systems foregrounding situated listening and collective accountability.
A diverse early Miocene (Burdigalian) turritelline-dominated assemblage (TDA) is documented from a single bed of the Nandana Member of the Gaj Formation, Dwarka Basin, western India. This study reports 42 gastropod species, including the description of four new species: ?Clelandella saurashtraensis n. sp., Jujubinus dwarkaensis n. sp., Cerithium bardhani n. sp., and Nassarius anisi n. sp. In addition, 30 species are discussed under open nomenclature. The TDA assemblage is notable for the high diversity among turritelline gastropods, with eight species identified across two genera, Turritella and Haustator. Petrographic studies and the foraminifera associations of Lockhartia sp., Miogypsina sp., Operculina sp., Quinqueloculina sp., and Ammonia sp., along with other foraminiferal groups such as nodosariids, milliolids, and rotalids, suggest that the TDA bed was deposited in tropical, warm, nutrient-rich, well-oxygenated conditions in subtidal–intertidal conditions.
The stability analysis of multiphase capillary wavetrains on water of infinite depth is performed using two coupled fourth-order nonlinear evolution (NLE) equations. We have investigated analytically the influence of a second wavetrain travelling in a different direction to the first wavetrain. The propagation of multiphase modes is studied for the case when group velocity projections of two wavetrains overlap. Criteria are derived for capillary Stokes wave instabilities and for the existence of a multiphase solitary envelope solution. We have exhibited that the weakly nonlinear multiphase capillary wavetrains in deep water is unstable to oblique disturbances and presented that the dominant modulational instability is two-dimensional in deep water. It is found that the growth rate of modulational instability increases with the increase of the angle of interaction between two wavetrains. The existing fourth-order analysis provides significant deviations on the stability results when compared with the third-order analysis.
We compute particle deposition rates on the back side of a cylinder at Reynolds numbers $\textit{Re}={1685}$, $6600$ and $10\,000$ using direct numerical simulation and Lagrangian particle tracking. We find that the deposition rates for $\textit{Re}={6600}$ and $10\,000$ are highly variable in time, with differences of up to a factor 27 in deposition rates between alternating low- and high-deposition-rate periods. The deposition-rate fluctuations are found at frequencies lower than the vortex-shedding frequency and therefore require long simulation times to be discovered. Additionally, we find that these fluctuations correlate positively with the drag and negatively with the cylinder base pressure. These observations imply that the back-side deposition process is governed by the low-frequency modulation of the cylinder wake. The high-deposition-rate regime is associated with a shorter wake and a more efficient turbulent transport of particles towards the cylinder surface, where the wake length modulation appears to have a more prominent effect. Consequently, the wake modulation controls the deposition rate but does not significantly affect the deposition mechanism. The back-side deposition has a maximum at Stokes number $St = 0.07$, as particles of lower Stokes number have too little inertia to deposit effectively and the deposition rate decorrelates from the wake fluctuations for larger Stokes numbers. These results highlight the strong sensitivity of the back-side deposition process to accurate descriptions of the wake turbulence over long enough times. These observations are critical when constructing accurate datasets for data-assisted methods to predict long-term back-side deposition on bluff bodies.
Early post-operative arrhythmia is a frequent complication after paediatric cardiac surgery. Although usually transient, it contributes to considerable morbidity and may increase mortality. This study aimed to determine the incidence, predictors, and outcomes of early post-operative arrhythmia following paediatric open-heart surgery.
Methodology:
A single-centre retrospective cohort study was conducted on paediatric patients who underwent open-heart surgery for congenital or acquired heart diseases between January 2022 and December 2024. Pre-operative, intraoperative, and post-operative parameters were analysed to identify independent predictors using multivariate logistic regression.
Results:
Of 2,096 patients analysed, 220 (10.5%) developed early post-operative arrhythmias, mainly tachyarrhythmias. The most common were complete heart block (3.2%), accelerated junctional rhythm (2.8%), and junctional ectopic tachycardia (1.9%). Tetralogy of Fallot repair had the highest incidence (20.2%). Independent predictors included prolonged cardiopulmonary bypass (OR 1.005, 95% CI 1.002–1.009, p = 0.002), extended aortic cross-clamp time (OR 1.006, 95% CI 1.001–1.011, p = 0.011), and prolonged inotropic support (OR 1.035, 95% CI 1.009–1.063, p = 0.009). Serum magnesium ≥ 1.0 mmol/L was identified as a protective factor. Arrhythmia was associated with longer mechanical ventilation (median 4 vs. 2 days), ICU stay (8 vs. 4 days), and hospitalisation (20 vs. 12 days; all p < 0.001). Mortality was higher but not statistically significant (5.9% vs. 3.6%, p = 0.087).
Conclusion:
Post-operative arrhythmia occurred in 10.5% of paediatric cardiac surgeries, most frequently after Tetralogy of Fallot repair. Prolonged bypass, aortic cross-clamp times, hypomagnesemia, and high inotropic support were independent risk factors associated with increased morbidity.