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It is known that for a uniform morphic sequence $\boldsymbol u = \langle u_n\rangle _{n=0}^\infty $ and an algebraic number $\beta $ such that $|\beta |>1$, the number $[\![ \boldsymbol {u} ]\!] _\beta :=\sum _{n=0}^\infty ({u_n}/{\beta ^n})$ either lies in $\mathbb Q(\beta )$ or is transcendental. In this paper, we show a similar rational–transcendental dichotomy for sequences defined by irreducible Pisot morphisms on binary alphabets. Subject to the Pisot conjecture (an irreducible Pisot morphism has pure discrete spectrum), we generalise the latter result to arbitrary finite alphabets. In certain cases, we are able to show transcendence of $[\![ \boldsymbol {u}]\!] _{\beta }$ outright. In particular, for $k\geq 2$, if $\boldsymbol u$ is the k-Bonacci word, then $[\![ \boldsymbol {u}]\!] _{\beta }$ is transcendental.
Reviving Gould and Lewontin’s critique of adaptationism, Singh’s subjective selection favors truth over useful simplification. Nonetheless, while psychologically plausible, its explanatory power remains limited. Moreover, by treating evolved psychology as fixed, it neglects gene-culture coevolution. The result is a vision of cultural evolution whose expansiveness risks outpacing its scientific utility.
Singh’s framework of subjective selection compellingly links individual cognition to cultural convergence. My commentary emphasizes that subjective selection is hierarchically mediated: not all individuals have equal capacity to shape or transmit their evaluations. Hierarchies of influence, authority, and interdependence determine whose perceptions are amplified into cultural traditions. Accounting for inequality and social power clarifies how the cultural manifold reflects both shared psychology and the unequal distribution of influence within human societies.
This commentary welcomes Singh’s shift from dual inheritance to individual psychology but argues that his model remains incomplete without evolutionary foundations. Cultural variants are not adopted merely because they appear useful – they appeal to evolved motivational systems shaped by natural selection. Integrating adaptive goals, producer–consumer dynamics, and ecological variation transforms subjective selection into a genuinely evolutionary-ecological framework.
Regulatory instruments are a key necessity to implement public-private partnership’s strategy. This study aimed to explore the stakeholders’ experience on financial incentive-based regulatory instruments for public-private partnership in Iran’s primary health care (PHC) delivery system.
Methods:
This qualitative study was involved face-to-face interviews with 18 stakeholders in primary health care partnership projects including employers, experts, contractors, and executive managers of contracted companies operating as a private health sector participant in primary health care services. The data were analyzed using the framework analysis method.
Results:
Twenty-four codes were developed. Findings showed that the current state of financial incentive-based regulatory instruments in Iran’s PHC delivery system faced some challenges despite existing capacities. These challenges include the lack of an independent trustee for access to capital, and a comprehensive regulatory program to facilitate private sector participants’ access to capital, and partnership contracting mechanisms. Findings also showed main challenges of these instruments related to access to capital, tax incentives and subsidies, staff mobility control mechanisms, partnership contracting mechanisms, and provider payments.
Conclusion:
The presence of significant challenges in Iran’s health care system can impact the private sector’s motivation to participate in primary health care. By improvement the infrastructure, reforming legal processes, and providing financial incentives, the government can boost the private sector’s motivation in primary health care and advance the health sector’s goals.
(1) identify risk factors for extended-spectrum beta-lactamase Klebsiella pneumoniae (ESBL-KP) acquisition in the neonatal intensive care unit (NICU) and (2) evaluate the clinical impact of ESBL-KP acquisition on neonatal outcomes at NICU discharge.
Design:
This retrospective case–control study (Aug 2022–Sept 2025) compared neonates who acquired ESBL-KP in the NICU (cases) with those who did not (controls).
Patients:
600 neonates admitted to a Kuwaiti NICU located in a general hospital.
Methods:
Data included clinical, demographic, antibiotic, and laboratory records. The primary outcome was ESBL-KP acquisition. The secondary outcome was status at NICU discharge. Regression analysis was used to evaluate associations for the primary and secondary outcomes.
Results:
Of 600 neonates, 30% acquired ESBL-KP. Among these, 12% had bloodstream infections (BSIs). Length of NICU stay (OR:1.02, 95% CI:1.01–1.03), intrauterine growth restriction (IUGR) (OR:2.59, 95% CI:1.08–6.24), extreme-prematurity (OR:2.89, 95% CI:1.29–6.47), previous hospital admission (OR:4.45, 95% CI:1.75–11.32), and prior ampicillin use (OR:3.51, 95% CI:2.12–5.82) were statistically significant risk factors for acquisition of ESBL-KP in the adjusted regression model. Moreover, ESBL-KP-positive neonates faced 12.83 times greater odds of death from sepsis (95 % CI: 2.41–68.22), than ESBL-KP negative neonates.
Conclusions:
ESBL-KP acquisition was strongly linked to IUGR, extreme prematurity, previous admission, and ampicillin use. While a longer hospital stay correlated with acquisition, this relationship is prone to time-dependent bias and reverse causation. Acquisition also raised sepsis-related mortality risk, though small sample sizes require cautious interpretation. Targeted prevention is essential to improve neonatal outcomes.
Singh compellingly describes some psychological factors that shape selection of cultural variants, but his approach gives insufficient attention to how culture shapes psychology. We argue the subjective selection account needs to pay greater attention to the psychological nuances of goal pursuit, cultural shaping of both perceived and “actual” effectiveness, and importance of social consensus cues.
Citizens do not directly observe democratic backsliding and, as a result, may hesitate to respond to subversion. We develop a model of third-party oversight bodies, such as the media or courts, that detect and assess actions that may be subversive to democracy and inform citizens. Oversight deters subversion, disciplines incumbents, and enables corrective actions by providing credible information about ambiguous incumbent behavior to citizens. However, when the oversight body is contested, citizens may doubt the intent behind its criticisms. When the oversight body is cautious in its criticisms, it elicits negative inferences about its intentions, what we term a fake news effect. The consequences are severe, undermining oversight and enabling backsliding. Democratic accountability depends on reliable sources of information and elected officials’ commitment to upholding norms of conduct.
Building on Beilinson’s work, ‘constructible sheaves are holonomic’, we introduce the notion of holonomicity for étale sheaves, without assuming a priori constructibility. We establish the converse of Beilinson’s result, showing that holonomic sheaves are indeed constructible. This can be seen as an étale analogue of Kashiwara’s theorem on holonomic ${\mathcal D}_X$-modules.
We study the identification of individual-level associations when only aggregate data are available. We characterize the biases of, and relationships among, canonical ecological inference (EI) estimators. We use these results to develop a partial identification approach: monotone EI. The approach exploits information about one or both of the following conditional associations: (1) outcome differences between groups within the same neighborhood and (2) outcome differences within the same group between neighborhoods with different group compositions. We show how assumptions about the sign of these conditional associations, whether individually or in relation to one another, can yield informative sharp bounds. We illustrate our results using county-level data to study differences in COVID-19 vaccination rates among Republicans and Democrats in the United States.
In this work, the life cycle of Gnathostoma turgidum was studied both in natural temporary water bodies and under experimental conditions, with materials collected from the municipality of San Francisco Ixhuatán, Oaxaca. Adult nematodes inhabit the interstitial layers of the stomach in the definitive host (Didelphis virginiana) and release their eggs into the environment via faeces, typically in a dry environment. Under these conditions, the eggs remain quiescent until the onset of the rainy season. Development of early third-stage larvae occurs in cyclopoid copepods. Fry acts as transport and/or intermediate hosts, while frogs (Lithobates forreri) serve as obligatory intermediate hosts for advanced third-stage larvae, ultimately transmitting the parasites to the definitive host. Notably, the precocity phenomenon, typical of larval development in intermediate hosts, occurs in this species within the definitive host. Precocity is likely a response to host behaviour or other ecological factors that restrict transmission to narrow spatial and temporal windows. Adults die at the end of the rainy season. The marked seasonality of this species is mainly attributed to the combination of two factors: (i) the seasonal predation of frogs by the definitive host, and (ii) expulsion of adult stages as immune-mediated ‘self-cure’. This study represents the first documentation of birds acting as paratenic hosts for this nematode.
Singh’s model accounts for cultural convergence but not moral progress. Historical expansions in moral status and the decline of cruel punishment constitute principled departures from parochial utility optimization. Empathy, reflective override, and institutional scaffolding support such breakthroughs. Moral progress therefore functions as a counter-attractor dynamic that enables systematic divergence from utility-based equilibria and requires explanatory resources beyond subjective selection alone.
High-resolution archaeometallurgical analysis of production debris offers a direct means of reconstructing ancient metalmaking traditions, yet remains underexplored relative to the study of finished artefacts. By integrating slag morphology, microstructure and compositional data from Late Bronze Age Taldysai, this study reconstructs, for the first time in Eurasian Steppe archaeology, a continuous 300-year tradition of copper-alloy production. The results reveal technological continuity alongside innovation, including advanced furnace designs, shared metallurgical knowledge and episodes of experimentation. The authors state that these findings position local semipastoralist communities not as peripheral adopters but as active innovators at the heart of Bronze Age Eurasian metallurgical developments.
Electrohydrodynamic (EHD) instabilities at the free deformable surface of thin nematic liquid crystal (NLC) films can generate large-area, self-organised, multi-scale surface morphologies under an external electrostatic field. In this work, we present a comprehensive investigation of EHD patterning in thin NLC films combining continuum-scale nonlinear simulations (NS) and molecular dynamics (MD). The multi-scale analysis identifies three principal morphological pathways: (i) no-patterning mode, observed at low electric fields; (ii) columnar mode, emerging above a critical field; and (iii) coalescence mode, characterised by lateral merging of patterns at higher field strengths. The NS further unveil two distinct pathways of the columnar mode – the secondary structure mode (SSM), exhibiting primary columns with secondary droplets; and the primary structure mode, featuring uniformly spaced primary columns. The SSM is favoured at low air-to-NLC filling ratios, where the additional elastic energy requirement to sustain anisotropic interfacial anchoring enhances surface deformation, forming multi-scale morphologies. The MD simulations additionally reveal a fundamental thermodynamic basis of EHD instability, dictating the patterning of NLC. The evolution, transition and tunability of these morphologies are governed by a complex interplay of field strength, filling ratio, anchoring anisotropy, elasticity and dielectric anisotropy. Parametric studies across this design space further offer strategies for tuning the prominence of secondary structures and arresting coalescence. The NS and MD simulations collectively reveal a bimodal orientational anisotropy, demonstrating the pattern’s function as a self-assembled photomask. These findings reveal the rich morphological diversity and surface functionality of NLC films, with promising applications in photolithography, electro-optic devices and adhesive systems.
Language exemplifies Singh’s super-attractor concept while testing the explanatory limits of subjective selection, which is just one of the processes of cultural evolution. Subjective selection explains many linguistic features through speakers’ instrumental goals. However, other types of processes also shape language evolution: some, related to learning and perception, for instance, will not involve intentions or conscious selection. Others involve intentionally creating and transforming linguistic constructions rather than merely selecting them from random mutations.
We praise many aspects of this paper that bring forward previously underemphasized content. We would caution against presenting it as an alternative group-level selection. Indeed, subjective selection may serve to generate a mechanistic understanding of the underlying system upon which group selection operates. Such an approach would address the circularity in the supposition that subjective selection explains cultural patterns.
A massive amount of research examines the representation of public opinion by policymakers, increasingly on actual policy actions. The work often provides evidence of a positive association between expressed public preferences and policy, but only some of the time and only to some degree, and there is even less evidence of responsiveness. This essay delves into the conditions for responsiveness, focusing on public demand for policy and policy supply, building on what research on the subjects reveals. The examination makes clear that policy responsiveness requires a great deal of both the represented and the representatives (and scholars too) and that these conditions are not easily met, though sometimes are. The emergent structure seemingly is much as empirical democratic theory would predict, and helps account for patterns of policy “responsiveness” we observe. The concluding section contemplates future research.