Let $\mathbb {Z}$ be the additive (semi)group of integers. We prove that for a finite semigroup S the direct product $\mathbb {Z}\times S$ contains only countably many subdirect products (up to isomorphism) if and only if S is regular. As a corollary we show that $\mathbb {Z}\times S$ has only countably many subsemigroups (up to isomorphism) if and only if S is completely regular.

Children’s externalizing behaviors are associated with impairments across the lifespan. Developmental psychopathology theories propose transactional (bidirectional) associations between child externalizing behaviors and parenting during childhood and adolescence. Yet, these foundational relations in early childhood are not well-studied. Utilizing a large, mixed-sex sample, we examined the reciprocal nature of parenting and child externalizing behaviors across early childhood using robust repeated-measures models. Repeated measures data were drawn from a socioeconomically diverse, longitudinal pregnancy cohort of 1287 (64% Black, 31% White) mother-child dyads at four time points (ages one to six). Three variables were included in cross-lagged panel models: observed parenting quality, child externalizing symptoms, and a maternal risk composite. In covariate-adjusted models, higher parenting quality at Wave 1 predicted lower child externalizing symptoms at Wave 2. Higher externalizing symptoms at Wave 1 and Wave 2 predicted lower parenting quality at Wave 2 and Wave 3, respectively. Maternal risk and parenting quality were not significantly associated. Findings showed both parent-driven and child-driven effects across early childhood that did not vary by child sex. The transactional nature of the parent-child relationship begins in infancy, underscoring the importance of early screening and provision of supports for families to minimize and prevent the development of serious psychopathology.

The mobility of rare-earth elements (REE) in low-grade diagenetic regimes, potentially leading to their clay-mediated fractionation, remains poorly understood. This study draws evidence from the argillitized Miocene tuff of the Southwestern Pannonian Basin (SPB) and adjacent Dinarides intramontane basins (DIB) to investigate the role of illite-smectite (I-S) in controlling early diagenetic REE behavior. The present research relies on detailed mineralogical, geochemical, and gas adsorption characterization of altered tuff, focusing on comparative analyses of the REE chemistry obtained by in situ laser ablation inductively coupled plasma mass spectrometry of glass shards and that of spatially related authigenic clay minerals. The depositional environment, in which the volcanic glass alteration took place, gave rise to the composition of secondary paragenesis, revealing a dominance of I-S. The normalized REE geochemistry of clay separates show similarities to unaltered glass, but notable differences indicate fluctuations in fluid/rock ratio environments. The redox conditions during glass alteration are reflected in Ce and Eu anomalies and indicate the ranges from oxic to anoxic across the analyzed tuffs. The results showed that I-S, formed through volcanic glass diagenesis, inherits magmatic REE signatures but also fractionates REE based on more reducing physiochemical conditions. The strong correlation between smectite content of I-S and a total budget of fractionated REE posits the smectite interlayers as prime factors controlling the REE fractionation during volcanic ash diagenesis. Furthermore, greater specific surface area values and development of slit-shaped porosity along the non-basal edges of I-S particles contributed to REE adsorption. These findings contribute to our understanding of REE behavior in low-temperature diagenetic environments, emphasizing the significance of clay minerals in retaining and fractionating these elements which may lead ultimately to the formation of economically viable ion-adsorption clay deposits.

A neglected, anonymous and undated epigram on the world map of Ptolemy’s Geography, here critically edited for the first time on the basis of all existing manuscripts, proves a rare case of reception of Callimachus’ Lock of Berenice, with an emphasis on the bonds between geography and astronomy, and with so-called ‘geographical astrology’. It may stem from Late Antique Alexandria.

Hypocrisy, when addressed at all, is typically considered a functional, even valuable, aspect of international political practice within international relations theory. It is alternatively seen as necessary to the exercise of sovereignty and a rhetorical device used to seek pragmatic political change. Utilising insights from feminist, queer, and postcolonial theory, this article challenges this understanding of hypocrisy. The article demonstrates that hypocrisy is animated and elided by an investment in a particularly liberal vision of politics and international order (and concomitant obfuscation of the racialised, sexual, gendered, and colonial underpinnings of those same assumptions). The notion of hypocrisy relies upon a unitary and stable subject whose moral consistency is to be expected across time and space – a luxury less afforded to those disadvantaged within intersectional international hierarchies. Consequently, although the charge of hypocrisy appears to be about holding power to account, the article finds that it serves less to uphold normative principles than to re-centre the privileged and powerful subject – typically, the sovereign state of liberal international order – and its consistency with itself, as the unit and basis of moral concern. The article concludes by outlining the limitations of hypocrisy as a strategy of critique.

The story of the Classic Maya “Snake” kingdom is truly a tale of two cities, with a capital that evidently switched from Dzibanche to Calakmul in the seventh century a.d. This article explores the era of transition between them in search of an elusive sequence of kings, while asking why the transfer came about and who played principal roles in it. Although grounded in finds at Calakmul, any attempt to answer complex questions of this nature must draw on a wider body of materials, both epigraphic and archaeological, from across the southern Maya Lowlands. Whatever portrait of the serpent kingdom is now possible, it is one that can only arise from close collaboration and the fusion of many scattered sources and clues.

Guidelines were created at our single centrer institution for which anesthesiology team should care for pediatric cardiac patients for noncardiac surgery. The goal of the survey was to assess inter-team dynamics after the implementation of guidelines and revealed that practice behaviour can quickly change but a sustained change in team dynamics and workplace culture takes time.

Cardona and Lario [‘Twists of the genus 2 curve $y^2 = x^6+1$’, J. Number Theory 209 (2020), 195–211] gave a complete classification of the twists of the curve $y^2 = x^6+1$. In this paper, we study the twists of the curve whose automorphism group is defined over a biquadratic extension of the rationals. If the twists are of type B or C in the Cardona–Lario classification, we find a pair of elliptic curves whose product is isogenous with the Jacobian of the twist.

Digital assets have burst onto global markets as a new class of assets for investment, trade and finance. Their growing popularity and economic relevance have been, however, accompanied by legal uncertainties and regulatory concerns. Together with domestic and regional responses, a strong case for international harmonisation is to be made. This Paper explores the emergence of principles and best practices on proprietary rights, insolvency and enforcement as a crucial process of international legal harmonisation of rules for digital assets.

This study investigated the combining ability, heterosis and heterotic grouping of maize (Zea mays L.) inbred lines to enhance hybrid performance and productivity. Twenty-four hybrids were developed by crossing eight inbred lines with three testers, and their performance was evaluated for two years at Banaras Hindu University's agricultural research farm. Data on yield and yield-attributing traits were collected from selectively centred competitive plants in each row, avoiding border plants to reduce errors. Biometrical techniques, cluster analysis, and statistical tools were employed to measure general combining ability (GCA), specific combining ability (SCA), and standard heterosis, providing insights into hybrid performance. Analysis of variance revealed significant mean square values for GCA and SCA across most traits studied. Various methods were utilized, including SCA effects, HGCAMT (Heterosis Grouping by Combining Ability of Multiple Traits), and HSGCA (Heterotic Grouping based on Specific and General Combining Ability). The study identified HUZM-242 × CML-286 and HUZM-53 × CML-286 as crosses displaying higher grain yield compared to the check line DKC 7074 and exhibiting positive heterosis. The findings offer valuable guidance for maize breeding programmes by accurately identifying heterotic groups, enabling breeders to select inbred lines more likely to produce high-performing hybrids. This targeted selection reduces the number of necessary cross-breeding trials, saving time and resources. Additionally, hybrids derived from crosses between lines from different heterotic groups exhibit superior performance due to higher heterosis. These conclusions support advancements in maize breeding strategies, ultimately contributing to agricultural sustainability through increased productivity, resource efficiency, and economic benefits for farmers.

Attention-deficit hyperactivity disorder (ADHD) and subclinical symptoms of hyperactivity-impulsivity and inattentiveness coincide with an increased risk of peer victimization. What remains unclear are the developmental dynamics of these associations. In a sample drawn from two Norwegian birth cohorts (n = 872; 49.94 % girls), assessed biennially from age 6 to age 14, reciprocal relations between ADHD symptoms and victimization were examined while controlling for symptoms of anxiety and depression. ADHD symptoms were assessed through clinical interviews with parents, whereas victimization was reported by teachers using questionnaires. Random-intercept cross-lagged panel modeling revealed a consistent reciprocal within-person effect of increased ADHD symptoms on victimization, and vice versa. Analyses of subdimensions of ADHD projected a consistent cross-lagged bidirectional relationship between victimization and inattentiveness symptoms only, whereas no such reciprocity was found for hyperactivity-impulsivity symptoms. Results did not differ by gender. Findings suggest that the social context may constitute a vulnerability factor in the etiology of the inattentive subtype of ADHD, and at the same time, that inattentiveness symptoms pose a risk for becoming victimized.

Streptococcus pneumoniae serotype 35B, a non-vaccine type, is a major contributor to the increase in pneumococcal infection post-vaccination. We aimed to understand the mechanism of its spread by characterizing 35B. The serotype, type 1 pilus (T1P) positivity, and antimicrobial susceptibility of 319 isolates in 2018–2022 were analysed and compared with those of isolates in 2014–2017 to find the changes. 35B accounted for 40 (12.5%) isolates. T1P positivity was notably higher in 35B (87.5%) than in the other serotypes. To confirm the role of T1P, an adhesion factor, we compared adherence to A549 cells between T1P-positive 35B isolates and their T1P-deficient mutants, showing contribution of T1P to adherence. Penicillin-non-susceptible rate of 35B was 87.5%, and meropenem-resistant 35B rate was 35.0%, which increased from 14.5% of 2014–2017 (p = 0.009). Multilocus sequence typing was performed in 35B strains. Prevalence of clonal complex 558, harbouring T1P and exhibiting multidrug non-susceptibility, suggested the advantages of 35B in attachment and survival in the host. The emergence of ST156 isolates, T1P-positive and non-susceptible to β-lactams, has raised concern about expansion in Japan. The increase of serotype 35B in pneumococcal diseases might have occurred due to its predominant colonizing ability after the elimination of the vaccine-serotypes.

Domestic abuse – abusive behaviour perpetrated by an adult towards another adult to whom they are personally connected (e.g. partners, ex-partners or family members) – damages mental health, increases mental health service use and challenges clinical management. Training and guidance for mental health professionals on identifying and responding to patients exposed to domestic abuse are available, but there has been less development of resources for mental health professionals in identifying, assessing and responding to perpetrators of domestic abuse. In this article, we describe a framework for responding to domestic abuse perpetration in clinical settings in general adult mental health services, aimed at improving practice. This could support mental health professionals in sensitive enquiry and assessment for domestic abuse perpetration, and guide appropriate responses, as part of routine training and continuing professional development.

This paper examines racial income inequality in early twentieth-century Puerto Rico. It finds, surprisingly, that Black men had an income advantage relative to White and Mulatto men in 1910–1920. The effect of race on income in Puerto Rico was smaller than that of other covariates such as urban status, sex, and literacy. A comparison with the state of Louisiana and with the United States as a whole in the same Census years shows that Puerto Rico was exceptional by U.S. standards, displaying much lower levels of racial inequality. Most of the income advantage Black men had can be attributed to the fact that they were more urban than Mulatto or White men, but part of this surprising advantage can be attributed to the existence in the countryside of a layer of skilled Black workers. Overall, Black men had equal or slightly higher occupational scores than Whites. The coexistence of slavery with other forms of coerced labor affecting individuals of all races in the nineteenth century, as well as the emergence of a stratum of Black skilled workers which survived into the twentieth century and thrived economically when the sugar industry experienced an explosive boom after 1898, is at the root of Black income equalization in the Puerto Rican countryside and in the island as a whole during the early twentieth century.